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Sample records for low-level laser irradiation

  1. Low-level laser irradiation induces in vitro proliferation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Barboza, Carlos Augusto Galvão; Ginani, Fernanda; Soares, Diego Moura; Henriques, Águida Cristina Gomes; Freitas, Roseana de Almeida

    2014-01-01

    To evaluate the effect of low-level laser irradiation on the proliferation and possible nuclear morphological changes of mouse mesenchymal stem cells. Mesenchymal stem cells derived from bone marrow and adipose tissue were submitted to two applications (T0 and T48 hours) of low-level laser irradiation (660nm; doses of 0.5 and 1.0J/cm"2). The trypan blue assay was used to evaluate cell viability, and growth curves were used to analyze proliferation at zero, 24, 48, and 72 hours. Nuclear alterations were evaluated by staining with DAPI (4'-6-diamidino-2-phenylindole) at 72 hours. Bone marrow-derived mesenchymal stem cells responded to laser therapy in a dose-dependent manner. Higher cell growth was observed when the cells were irradiated with a dose of 1.0J/cm"2, especially after 24 hours (p<0.01). Adipose-derived mesenchymal stem cells responded better to a dose of 1.0J/cm"2, but higher cell proliferation was observed after 48 hours (p<0.05) and 72 hours (p<0.01). Neither nuclear alterations nor a significant change in cell viability was detected in the studied groups. Low-level laser irradiation stimulated the proliferation of mouse mesenchymal stem cells without causing nuclear alterations. The biostimulation of mesenchymal stem cells using laser therapy might be an important tool for regenerative therapy and tissue engineering

  2. Low-level laser irradiation induces in vitro proliferation of mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Barboza, Carlos Augusto Galvão; Ginani, Fernanda [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil); Soares, Diego Moura [Universidade Federal de Pernambuco, Recife, PE (Brazil); Henriques, Águida Cristina Gomes; Freitas, Roseana de Almeida [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)

    2014-07-01

    To evaluate the effect of low-level laser irradiation on the proliferation and possible nuclear morphological changes of mouse mesenchymal stem cells. Mesenchymal stem cells derived from bone marrow and adipose tissue were submitted to two applications (T0 and T48 hours) of low-level laser irradiation (660nm; doses of 0.5 and 1.0J/cm{sup 2}). The trypan blue assay was used to evaluate cell viability, and growth curves were used to analyze proliferation at zero, 24, 48, and 72 hours. Nuclear alterations were evaluated by staining with DAPI (4'-6-diamidino-2-phenylindole) at 72 hours. Bone marrow-derived mesenchymal stem cells responded to laser therapy in a dose-dependent manner. Higher cell growth was observed when the cells were irradiated with a dose of 1.0J/cm{sup 2}, especially after 24 hours (p<0.01). Adipose-derived mesenchymal stem cells responded better to a dose of 1.0J/cm{sup 2}, but higher cell proliferation was observed after 48 hours (p<0.05) and 72 hours (p<0.01). Neither nuclear alterations nor a significant change in cell viability was detected in the studied groups. Low-level laser irradiation stimulated the proliferation of mouse mesenchymal stem cells without causing nuclear alterations. The biostimulation of mesenchymal stem cells using laser therapy might be an important tool for regenerative therapy and tissue engineering.

  3. Role of laser fluence in protein synthesis of cultured DRG neurons following low-level laser irradiation

    Science.gov (United States)

    Zheng, Liqin; Qiu, Caimin; Wang, Yuhua; Zeng, Yixiu; Yang, Hongqin; Zhang, Yanding; Xie, Shusen

    2014-11-01

    Low-level lasers have been used to relieve pain in clinical for many years. But the mechanism is not fully clear. In animal models, nitric oxide (NO) has been reported involving in the transmission and modulation of nociceptive signals. So the objective of this study was to establish whether low-level laser with different fluence could stimulate the production of nitric oxide synthese (NOS), which produces NO in cultured primary dorsal root ganglion neurons (DRG neurons). The primary DRG neurons were isolated from healthy Sprague Dawley rats (8-12 weeks of age) and spread on 35 mm culture dishes specially used for confocal microscopy. 24 hours after spreading, cells were irradiated with 658 nm laser for two consecutive days at the energy density of 20, 40, 60 and 80 mJ·cm-2 respectively. Control groups were not exposed to the laser, but were kept under the same conditions as the irradiated ones. The synthesis of NOS after laser irradiation was detected by immunofluorescence assay, and the changes of NOS were evaluated using confocal microscopy and Image J software. The results showed that all the laser fluence could promote the production of NOS in DRG neurons, especially the 60 mJ·cm-2 . These results demonstrated that low-level laser irradiation could modify protein synthesis in a dose- or fluence- dependent manner, and indicated that low-level laser irradiation might achieve the analgesic effect through modulation of NO production.

  4. In vitro analysis of low-level laser irradiation on human osteoblast-like cells proliferation

    Science.gov (United States)

    Bloise, Nora; Saino, Enrica; Bragheri, Francesca; Minzioni, Paolo; Cristiani, Ilaria; Imbriani, Marcello; Visai, Livia

    2011-07-01

    The objective of this study was to examine the in vitro effect of a single or a multiple doses of low-level laser irradiation (LLLI) on proliferation of the human osteosarcoma cell line, SAOS-2. SAOS-2 cells were divided in five groups and exposed to LLLI (659 nm diode laser; 11 mW power output): group I as a control (dark), group II exposed to a single laser dose of 1 J/cm2, group III irradiated with a single dose of 3 J/cm2, and group IV and V exposed for three consecutive days to 1 or 3 J/cm², respectively. Cellular proliferation was assessed daily up to 7 days of culturing. The obtained results showed an increase in proliferative capacity of SAOS-2 cells during the first 96 h of culturing time in once-irradiated cells, as compared to control cells. Furthermore, a significantly higher proliferation in the group IV and V was detected if compared to a single dose or to control group after 96 h and 7 days. In conclusion, the effect of the single dose on cell proliferation was transitory and repeated irradiations were necessary to observe a strong enhancement of SAOS-2 growth. As a future perspective, we would like to determine the potential of LLLI as a new approach for promoting bone regeneration onto biomaterials.

  5. Low-level laser irradiation protects the chick embryo chorioallantoic membrane from UV cytotoxicity

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    Hammami Amira

    2018-01-01

    Full Text Available Low-level laser therapy or photobiomodulation is the medical use of a very low intensity light in the red to near infrared (wavelengths in the range of 630-940 nm. The present work was conducted to explore the effects of both UV and low-level laser irradiation (LLLI on microcirculation using the in vivo model of the chick embryo chorioallantoic membrane (CAM. The effects were assessed by measuring lipid peroxidation and antioxidant enzyme activity. Cell cytotoxicity, survival and intracellular reactive oxygen species (ROS of the CAM were also evaluated. We found that UV irradiation induced alterations of the vessels, leading to bleeding and extravasation. This effect was intensified after 60 min of exposure to UV irradiation, leading to marked edema. UVA irradiation increased cell cytotoxicity as assessed by lactate dehydrogenase (LDH release (56.23% of control and reduced cell viability as assessed by decreased fluorescein diacetate (FDA fluorescence (56.23% of control. Pretreatment with LLLI prior to UV exposure protected the CAM tissue from UV-mediated cell death. This protective effect was supported by the observation of significantly inhibited lipid peroxidation (from 0.3±0.004 for UV, to 0.177±0.012 after LLLI pretreatment, ROS and O2 -production, as indicated by respective dihydrorhodamine (DHR and dihydroethidium (DHE intensities (from 132.78% of control for UVA, to 95.90% of control for L-UV (DHR, and from 127.34% of control for UVA, to 82.03% of control for L-UV (DHE, and by preventing the increase in oxidative activities. LLLI efficiently protected CAM cells from UV-induced oxidative stress and appeared as a safe protective pretreatment against UV irradiation.

  6. Effects of increased low-level diode laser irradiation time on extraction socket healing in rats.

    Science.gov (United States)

    Park, Joon Bong; Ahn, Su-Jin; Kang, Yoon-Goo; Kim, Eun-Cheol; Heo, Jung Sun; Kang, Kyung Lhi

    2015-02-01

    In our previous studies, we confirmed that low-level laser therapy (LLLT) with a 980-nm gallium-aluminum-arsenide diode laser was beneficial for the healing of the alveolar bone in rats with systemic disease. However, many factors can affect the biostimulatory effects of LLLT. Thus, we attempted to investigate the effects of irradiation time on the healing of extraction sockets by evaluating the expressions of genes and proteins related to bone healing. The left and right first maxillary molars of 24 rats were extracted. Rats were randomly divided into four groups in which extraction sockets were irradiated for 0, 1, 2, or 5 min each day for 3 or 7 days. Specimens containing the sockets were examined using quantitative real-time reverse transcription polymerase chain reaction and western blotting. LLLT increased the expressions of all tested genes, Runx2, collagen type 1, osteocalcin, platelet-derived growth factor-B, and vascular endothelial growth factor, in a time-dependent manner. The highest levels of gene expressions were in the 5-min group after 7 days. Five minutes of irradiation caused prominent increases of the expression of all tested proteins after both 3 and 7 days. The expression level of each protein in group 4 was higher by almost twofold compared with group 1 after 7 days. Laser irradiation for 5 min caused the highest expressions of genes and proteins related to bone healing. In conclusion, LLLT had positive effects on the early stages of bone healing of extraction sockets in rats, which were irradiation time-dependent.

  7. assessment Of the effect Of low Level Laser Therapy on Parotid glands of gamma Irradiated Rats

    International Nuclear Information System (INIS)

    Ahmed, S.F.

    2013-01-01

    Gamma radiation-induced salivary gland dysfunction has a major deleterious effect on oral health. Aim: This study was carried out to evaluate the possible effect of low level laser therapy (LLLT) on radiation induced oxidative stress in rats’ salivary glands. Material and Methods: Sixty four male Albino rats were divided into two groups. One group where the left parotid gland was exposed to 3 sessions of LLL, then rats were subjected to 3 sessions of whole body gamma-radiation. In the other group, rats were subjected to 3 sessions of gamma-radiation; each was followed by a session of LLL to the left parotid gland. The right gland of both groups was used as irradiated control. Parotid glands were collected 1 day, 3 days, 1 week and 2 weeks after the end of treatment and were subjected to histological examination and immunohistochemical analysis. Results: The parotid gland of both laser groups showed less intra cytoplasmic vacuolisation, slight alteration of acinar architecture and almost even size nuclei as compared to the irradiated gland. LLL either before or parallel to gamma-irradiation was effective in increasing cell proliferation on the third and seventh day, respectively as compared to the gamma irradiated group (P<0.05). Statistically, results revealed significant decrease in optical density of caspase 3 activity in the lased groups on the first week as compared to the control. Conclusion: LLLT attenuates the harmful effect of gamma irradiation on the parotid glands of the rats. Also, it improves gland regeneration through modulation of cell proliferation and apoptosis inflammation

  8. The effects of low level laser irradiation on proliferation of human dental pulp: a narrative review.

    Science.gov (United States)

    Staffoli, S; Romeo, U; Amorim, R N S; Migliau, G; Palaia, G; Resende, L; Polimeni, A

    2017-01-01

    Mesenchymal stem cells (MSCs) have the capability for self-renewal, proliferation, and differentiation in various types of specialized cells, so they are very important in cellular therapies. MSC from dental pulp are simply obtainable and have high proliferative capability. Among the therapies that can stimulate the proliferation of certain cell types, low-level laser therapy (LLLT) stands out. The target of this study is to perform a literature review to investigate these effects of low-level laser irradiation on proliferation of human dental pulp.The electronic search of scientific papers was conducted in the Lilacs, Scielo, Medline and PubMed databases through scientific articles published in national and international journals in the past 20 years.The results of this review suggest that LLLT may be a useful and important tool for future advances in cell therapy and tissue engineering associated to stem cells. Studies on cell therapy for regenerating dental tissues has already been done, and shows promising results.

  9. Biological effects of low-level laser irradiation on umbilical cord mesenchymal stem cells

    International Nuclear Information System (INIS)

    Chen, Hongli; Wang, Hong; Li, Yingxin; Liu, Weichao; Chen, Zhuying; Wang, Chao

    2016-01-01

    Low-level laser irradiation (LLLI) can enhance stem cell (SC) activity by increasing migration and proliferation. This study investigated the effects of LLLI on proliferation, enzymatic activity, and growth factor production in human umbilical cord mesenchymal SCs (hUC-MSCs) as well as the underlying mechanisms. hUC-MSCs were assigned to a control group (non-irradiation group) and three LLLI treatment groups (635 nm group, 808 nm group, and 635/808 nm group). Laser power density and energy density of 20 mW/cm"2 and 12 J/cm"2, respectively, were used for each experiment. The proliferation rate was higher in the 635 nm as compared to the other groups. LLLI at 808 nm did not induce cell proliferation. ROS levels in cells exposed to 635, 808, and 635/808 nm radiation were increased by 52.81%, 26.89%, and 21.15%, respectively, relative to the control group. CAT, tGPx, and SOD activity was increased. LLLI at 808 nm increased the levels of IL-1, IL-6, and NFκB but not VEGF. LLLI improved hUC-MSCs function and increased antioxidant activity. Dual-wavelength LLLI had more potent effects on hUC-MSCs than single-wavelength treatment. LLLI has potential applications in the preconditioning of hUC-MSCs in vitro prior to transplantation, which could improve the regenerative capacity of cells.

  10. Biological effects of low-level laser irradiation on umbilical cord mesenchymal stem cells

    Science.gov (United States)

    Chen, Hongli; Wang, Hong; Li, Yingxin; Liu, Weichao; Wang, Chao; Chen, Zhuying

    2016-04-01

    Low-level laser irradiation (LLLI) can enhance stem cell (SC) activity by increasing migration and proliferation. This study investigated the effects of LLLI on proliferation, enzymatic activity, and growth factor production in human umbilical cord mesenchymal SCs (hUC-MSCs) as well as the underlying mechanisms. hUC-MSCs were assigned to a control group (non-irradiation group) and three LLLI treatment groups (635 nm group, 808 nm group, and 635/808 nm group). Laser power density and energy density of 20 mW/cm2 and 12 J/cm2, respectively, were used for each experiment. The proliferation rate was higher in the 635 nm as compared to the other groups. LLLI at 808 nm did not induce cell proliferation. ROS levels in cells exposed to 635, 808, and 635/808 nm radiation were increased by 52.81%, 26.89%, and 21.15%, respectively, relative to the control group. CAT, tGPx, and SOD activity was increased. LLLI at 808 nm increased the levels of IL-1, IL-6, and NFκB but not VEGF. LLLI improved hUC-MSCs function and increased antioxidant activity. Dual-wavelength LLLI had more potent effects on hUC-MSCs than single-wavelength treatment. LLLI has potential applications in the preconditioning of hUC-MSCs in vitro prior to transplantation, which could improve the regenerative capacity of cells.

  11. Biological effects of low-level laser irradiation on umbilical cord mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hongli; Wang, Hong; Li, Yingxin, E-mail: yingxinli2005@126.com; Liu, Weichao; Chen, Zhuying [Key Laboratory of Laser Medicine of Tianjin, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192 (China); Wang, Chao [Biomedical Engineering and Technology College, Tianjin Medical University, Tianjin, 300070 (China)

    2016-04-15

    Low-level laser irradiation (LLLI) can enhance stem cell (SC) activity by increasing migration and proliferation. This study investigated the effects of LLLI on proliferation, enzymatic activity, and growth factor production in human umbilical cord mesenchymal SCs (hUC-MSCs) as well as the underlying mechanisms. hUC-MSCs were assigned to a control group (non-irradiation group) and three LLLI treatment groups (635 nm group, 808 nm group, and 635/808 nm group). Laser power density and energy density of 20 mW/cm{sup 2} and 12 J/cm{sup 2}, respectively, were used for each experiment. The proliferation rate was higher in the 635 nm as compared to the other groups. LLLI at 808 nm did not induce cell proliferation. ROS levels in cells exposed to 635, 808, and 635/808 nm radiation were increased by 52.81%, 26.89%, and 21.15%, respectively, relative to the control group. CAT, tGPx, and SOD activity was increased. LLLI at 808 nm increased the levels of IL-1, IL-6, and NFκB but not VEGF. LLLI improved hUC-MSCs function and increased antioxidant activity. Dual-wavelength LLLI had more potent effects on hUC-MSCs than single-wavelength treatment. LLLI has potential applications in the preconditioning of hUC-MSCs in vitro prior to transplantation, which could improve the regenerative capacity of cells.

  12. Low Level (Sub Threshold), Large Spot Laser Irradiations of the Foveas of Macaca Mulatta.

    Science.gov (United States)

    1981-11-01

    spherules. In a portion of the block containing the macula a degenerating patch is seen, displaying considerable edema, with pyknotic and missing nuclei...6 Peripheral areas 11 Macula 11 Eye # 3 M31 2KD 15 (enucleated 7 days after focal irradiation jby gallium arsenide laser). Control areas 15 Neodymium...laser irradiations peripheral areas 23 Macula 28 TABLE OF CONTENTS continued Page Eye # 5 M443 2JD Patched Eye 32 Most areas 32 area nasal to optic disc

  13. Effects of Low-Level Laser Irradiation on the Pathogenicity of Candida albicans: In Vitro and in Vivo Study

    NARCIS (Netherlands)

    Seyedmousavi Tasieh, S.; Hashemi, S.J.; Rezaie, S.; Fateh, M.; Djavid, G.E.; Zibafar, E.; Morsali, F.; Zand, N.; Alinaghizadeh, M.; Ataie-Fashtami, L.

    2014-01-01

    Abstract Objective: The purpose of this study was to evaluate the effects of low-level laser irradiation (LLLI) on the in vitro growth characteristics and in vivo pathogenicity of Candida albicans in a murine model in the absence of a photosensitizer. Background data: C. albicans is an opportunistic

  14. Photobiostimulation on chondrocytes proliferation in different concentration of fetal bovine serum under low-level laser irradiation

    Science.gov (United States)

    Zheng, Liqin; Wang, Yuhua; Qiu, Caimin; Chen, Jianlin; Yang, Hongqin; Zhang, Yanding; Xie, Shusen

    2015-03-01

    The aim of this in vitro study was to evaluate the influence of low-level laser irradiation (LLLI) on the chondrocytes proliferation cultured in different concentration of fetal bovine serum (FBS) using 658 nm, 785 nm and 830 nm diode lasers. The role of energy density (10-70 mJ·cm-2) on chondrocytes proliferation following irradiation with 658 nm laser for 2 days was firstly investigated to find out the best laser energy density. Then the effect of LLLI on the proliferation of chondrocytes cultured with fetal bovine serum at 0%, 2%, 5% and 10% was also evaluated. The results showed that there was no or little photobiostimulation on the proliferation of chondrocytes cultured with 0% FBS and 10% FBS; the cell proliferation at 2% and 5% FBS was significantly modulated by LLLI.

  15. Low-level laser irradiation promotes the proliferation and maturation of keratinocytes during epithelial wound repair

    Science.gov (United States)

    Sperandio, Felipe F.; Simões, Alyne; Corrêa, Luciana; Aranha, Ana Cecília C.; Giudice, Fernanda S.; Hamblin, Michael R.; Sousa, Suzana C.O.M.

    2015-01-01

    Low-level laser therapy (LLLT) has been extensively employed to improve epithelial wound healing, though the exact response of epithelium maturation and stratification after LLLT is unknown. Thus, this study aimed to assess the in vitro growth and differentiation of keratinocytes (KCs) and in vivo wound healing response when treated with LLLT. Human KCs (HaCaT cells) showed an enhanced proliferation with all the employed laser energy densities (3, 6 and 12 J/cm2, 660nm, 100mW), together with an increased expression of Cyclin D1. Moreover, the immunoexpression of proteins related to epithelial proliferation and maturation (p63, CK10, CK14) all indicated a faster maturation of the migrating KCs in the LLLT-treated wounds. In that way, an improved epithelial healing was promoted by LLLT with the employed parameters; this improvement was confirmed by changes in the expression of several proteins related to epithelial proliferation and maturation. PMID:25411997

  16. Over-expression of CXCR4, a stemness enhancer, in human blastocysts by low level laser irradiation

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Tahmasbi

    2013-09-01

    Full Text Available The key role of chemokine receptor CXCR4 in the maintenance of stemness property of stem cells has been shown recently. The low level laser irradiation (LLLI is being used currently in a wide variety of clinical cases as a therapeutic tool for wound healing, relieving pain and destroying tumor cells. The aim of this study was to evaluate the effect of LLLI mimicking low level laser therapy (LLLT on the expression level of CXCR4 gene a few hours after irradiation on human blastocysts. After the development of human embryos to the first grade blastocyst stage, they were irradiated with a low power Ga-Al-As laser at a continuous wavelength of 650 nm and a power output of 30 mW. The total RNA of the irradiated blastocysts and control groups were isolated in groups of 1x2 J/cm2, 2x2 J/cm2, 1x4 J/cm2 and 2x4 J/cm2 LLLI. Specific Real-Time PCR primers were designed to amplify all the two CXCR4 isoforms yet identified. RNA amplifications were done for all the groups. We showed for the first time that LLLI makes the human blastocysts to increase the expression level of CXCR4 a few hours after irradiation. Moreover, it was shown that two irradiation doses with one day interval can cause a significant increase in CXCR4 expression level in human blastocysts. This study revealed that LLLI could be a proliferation motivator for embryonic cell divisions through enhanced over-expression of CXCR4 level.

  17. Aquaporin-1-Mediated Effects of Low Level He-Ne Laser Irradiation on Human Erythrocytes

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    Gang-Yue Luo

    2012-01-01

    Full Text Available The role of membrane aquaporin-1 (APQ-1 in the photobiomodulation (PBM on erythrocyte deformability will be studied in this paper with human dehydrated erythrocytes as echinocytic shape alterations lead to decreased cellular deformability. Human dehydrated erythrocytes were irradiated with low intensity He-Ne laser irradiation (LHNL at 0.9, 1.8, 2.7, and 4.4 mW/cm2 for 5, 15, and 30 min, respectively, and APQ-1 inhibitor, 0.2 μmol/L HgCl2, was used to study the role of APQ-1 in mediating PBM with LHNL at 4.4 mW/cm2 for 5 min. Comprehensive morphological parameters of an intact cell such as contact area, perimeter, roundness and erythrocyte elongation index (EEI were measured to characterize erythrocyte deformability with fast micro multi-channel spectrophotometer. It was observed that the dosage of LHNL improvement of the morphological parameters of dehydrated erythrocytes was morphological-parameter-dependent, but the Bunsen-Roscoe rule did not hold for roundness. The LHNL at 4.4 mW/cm2 for 5 min significantly improved the contact area (P<0.05 and EEI (P<0.05 of the dehydrated erythrocytes, but the improvement was significantly inhibited by 0.2 μmol/L HgCl2 (P<0.05. It was concluded that AQP-1 might mediate the effects of LHNL on erythrocyte deformability, which supports the membranotropic mechanism of PBM.

  18. Ultrastructure and Light Microscope Analysis of Intact Skin after a Varying Number of Low Level Laser Irradiations in Mice

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    Mamie Mizusaki Iyomasa

    2014-01-01

    Full Text Available Low level laser therapy (LLLT has been used to relieve pain, inflammation, and wound healing processes. Thus, the skin is overexposed to laser and this effect is not completely understood. This study analyzed the effects of the number of laser applications (three, six, and 10 on the intact skin of the masseteric region in mice of strain HRS/J. The animals (n=30 were equally divided into control (0 J/cm2 and irradiated (20 J/cm2, and each of these groups was further equally divided according to the number of laser applications (three, six, and 10 and underwent LLLT on alternate days. Samples were analyzed by light microscopy and transmission electron microscope (TEM. The animals receiving applications exhibited open channels more dilated between the keratinocytes and photobiomodulation effect on endothelial cells and fibroblasts by TEM. Under the light microscope after 10 laser applications, the type I collagen decreased (P<0.05 compared to the three and six applications. Under these experimental conditions, all numbers of applications provided photobiomodulatory effect on the epidermis and dermis, without damage. More studies are needed to standardize the energy density and number of applications recommended for laser therapy to have a better cost-benefit ratio associated with treatment.

  19. Effects of low-level laser irradiation on the pathogenicity of Candida albicans: in vitro and in vivo study.

    Science.gov (United States)

    Seyedmousavi, Seyedmojtaba; Hashemi, Seyed Jamal; Rezaie, Sasan; Fateh, Mohsen; Djavid, Gholamreza Esmaeeli; Zibafar, Ensieh; Morsali, Farhad; Zand, Nasrin; Alinaghizadeh, Mohammadreza; Ataie-Fashtami, Leila

    2014-06-01

    The purpose of this study was to evaluate the effects of low-level laser irradiation (LLLI) on the in vitro growth characteristics and in vivo pathogenicity of Candida albicans in a murine model in the absence of a photosensitizer. C. albicans is an opportunistic commensal organism that causes a wide variety of diseases in human beings, ranging from superficial infections to life-threatening invasive candidiasis. The incidence of C. albicans infection is increasing, because of the greater frequency of acquired immunodeficiency conditions. A high recurrence rate has been reported for vulvovaginal and oral candidiasis, despite the best available treatments. Therefore, the search for new treatment modalities seems quite rational. Candida culture plates were exposed to common clinical energies of LLLI: 3, 5, 10, and 20 J at 685 nm (BTL Laser 5000, Medicinos Projektai, Czech Republic, Prague, max power output 50 mW) and 3, 5, 10, 30, and 50 J at 830 nm (BTL Laser 5000, Medicinos Projektai, Czech Republic, Prague, max power output 400 mW). Following LLLI with energies >10 J at both 685 and 830 nm wavelengths, statistically significant effects were observed in vitro on the turbidimetric growth kinetics of C. albicans and in vivo on the survival rate of infected mice (p value ≤ 0.05). Therefore, this energy could be considered a threshold for clinical investigation. Translating our data into the clinical setting, it can be proposed that a direct laser-based approach without using a photosensitizing dye can significantly reduce the pathogenicity of Candida albicans. It can also be concluded that laser light at specific wavelengths could be a possible promising novel treatment for superficial and mucocutaneous C. albicans infections.

  20. Effect of low-level laser irradiation on osteoblast-like cells cultured on porous hydroxyapatite scaffolds

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    Serena Incerti Parenti

    2013-09-01

    Full Text Available OBJECTIVE: To determine the effect of laser irradiation at a low dose on human osteoblastlike cells. Materials and methods: 32 porous hydroxyapatite scaffolds currently used for bone tissue engineering were seeded with MG63 cells and irradiated or not with a GaAlAs diode laser (wavelength 915 nm, dose 2 J/cm² using different power density and exposure duration. RESULTS: After 72-h incubation, cells showed well spread morphology and good adhesion on both laser-treated and untreated scaffolds. Laser irradiation did not interfere in cell viability and proliferation as compared with the non-irradiated controls. CONCLUSION: This study suggests that there is no effect of 915 nm laser irradiation at a dose of 2 J/cm² on the proliferation rate of MG63 cells. Future investigations are needed to compare different dose and wavelength regimens in order to determine the optimal set of laser parameters for maximum cell yield and safe clinical application.

  1. Preconditioning With Low-Level Laser Irradiation Enhances the Therapeutic Potential of Human Adipose-derived Stem Cells in a Mouse Model of Photoaged Skin.

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    Liao, Xuan; Li, Sheng-Hong; Xie, Guang-Hui; Xie, Shan; Xiao, Li-Ling; Song, Jian-Xing; Liu, Hong-Wei

    2018-02-19

    This study was conducted to explore the therapeutic potential of human adipose-derived stem cells (ADSCs) irradiated with a low-level laser (LLL). Cultured ADSCs were treated with 650-nm GaAlAs laser irradiation at 2, 4 and 8 J cm -2 . Cell proliferation was quantified by MTT assays, cytokine secretion was determined by enzyme-linked immunosorbent assays, and adipogenic differentiation was examined by oil red O staining. Additionally, the expression profiles of putative ADSC surface markers were analyzed by quantitative real-time PCR. In addition, a mouse photoaged skin model was established by UVB irradiation. Effects of GaAlAs laser-treated ADSCs on the thicknesses of the epidermis and dermis were analyzed by hematoxylin and eosin staining. The results showed that GaAlAs laser treatment of cells at a radiant exposure of 4 J cm -2 enhanced ADSC proliferation and adipogenic differentiation and increased secretion of growth factors. Furthermore, GaAlAs laser irradiation upregulated the expression of putative ADSC surface markers. In the mouse model of photoaged skin, ADSCs treated with GaAlAs laser irradiation had markedly decreased the epidermal thickness and increased the dermal thickness of photoaged mouse skin. Our data indicate that LLL irradiation is an effective biostimulator of ADSCs and might enhance the therapeutic potential of ADSCs for clinical use. © 2018 The American Society of Photobiology.

  2. The effect of low-level laser irradiation (In-Ga-Al-AsP - 660 nm) on melanoma in vitro and in vivo

    International Nuclear Information System (INIS)

    Frigo, Lúcio; Luppi, Juliana SS; Favero, Giovani M; Maria, Durnavei A; Penna, Sócrates C; Bjordal, Jan M; Bensadoun, Rene J; Lopes-Martins, Rodrigo AB

    2009-01-01

    It has been speculated that the biostimulatory effect of Low Level Laser Therapy could cause undesirable enhancement of tumor growth in neoplastic diseases. The aim of the present study is to analyze the behavior of melanoma cells (B16F10) in vitro and the in vivo development of melanoma in mice after laser irradiation. We performed a controlled in vitro study on B16F10 melanoma cells to investigate cell viability and cell cycle changes by the Tripan Blue, MTT and cell quest histogram tests at 24, 48 and 72 h post irradiation. The in vivo mouse model (male Balb C, n = 21) of melanoma was used to analyze tumor volume and histological characteristics. Laser irradiation was performed three times (once a day for three consecutive days) with a 660 nm 50 mW CW laser, beam spot size 2 mm 2 , irradiance 2.5 W/cm 2 and irradiation times of 60s (dose 150 J/cm 2 ) and 420s (dose 1050 J/cm 2 ) respectively. There were no statistically significant differences between the in vitro groups, except for an increase in the hypodiploid melanoma cells (8.48 ± 1.40% and 4.26 ± 0.60%) at 72 h post-irradiation. This cancer-protective effect was not reproduced in the in vivo experiment where outcome measures for the 150 J/cm 2 dose group were not significantly different from controls. For the 1050 J/cm 2 dose group, there were significant increases in tumor volume, blood vessels and cell abnormalities compared to the other groups. LLLT Irradiation should be avoided over melanomas as the combination of high irradiance (2.5 W/cm 2 ) and high dose (1050 J/cm 2 ) significantly increases melanoma tumor growth in vivo

  3. Low-level ultrahigh-frequency and ultrashort-pulse blue laser irradiation enhances osteoblast extracellular calcification by upregulating proliferation and differentiation via transient receptor potential vanilloid 1.

    Science.gov (United States)

    Mikami, Risako; Mizutani, Koji; Aoki, Akira; Tamura, Yukihiko; Aoki, Kazuhiro; Izumi, Yuichi

    2018-04-01

    Low-level laser irradiation (LLLI) exerts various biostimulative effects, including promotion of wound healing and bone formation; however, few studies have examined biostimulation using blue lasers. The purpose of this study was to investigate the effects of low-level ultrahigh-frequency (UHF) and ultrashort-pulse (USP) blue laser irradiation on osteoblasts. The MC3T3-E1 osteoblast cell line was used in this study. Following LLLI with a 405 nm newly developed UHF-USP blue laser (80 MHz, 100 fs), osteoblast proliferation, and alkaline phosphatase (ALP) activity were assessed. In addition, mRNA levels of the osteoblast differentiation markers, runt-related transcription factor 2 (Runx2), osterix (Osx), alkaline phosphatase (Alp), and osteopontin (Opn) was evaluated, and extracellular calcification was quantified. To clarify the involvement of transient receptor potential (TRP) channels in LLLI-induced biostimulation, cells were treated prior to LLLI with capsazepine (CPZ), a selective inhibitor of TRP vanilloid 1 (TRPV1), and subsequent proliferation and ALP activity were measured. LLLI with the 405 nm UHF-USP blue laser significantly enhanced cell proliferation and ALP activity, compared with the non-irradiated control and LLLI using continuous-wave mode, without significant temperature elevation. LLLI promoted osteoblast proliferation in a dose-dependent manner up to 9.4 J/cm 2 and significantly accelerated cell proliferation in in vitro wound healing assay. ALP activity was significantly enhanced at doses up to 5.6 J/cm 2 , and expression of Osx and Alp mRNAs was significantly increased compared to that of the control on days 3 and 7 following LLLI at 5.6 J/cm 2 . The extent of extracellular calcification was also significantly higher as a result of LLLI 3 weeks after the treatment. Measurement of TRPV1 protein expression on 0, 3, and 7 days post-irradiation revealed no differences between the LLLI and control groups; however, promotion of cell

  4. Adaptive response after low level irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Pelevina, I I; Afanasjev, G G; JaGotlib, V; Tereschenko, D G; Tronov, V A; Serebrjany, A M [Russian Academy of Sciences, Moscow (Russian Federation). Institute of Chemical Physics

    1996-02-01

    The experiments conducted on cultured HeLa (tissue culture) cells revealed that there is a limit of dose above which adaptive response was not observed and a limit of dose below which this response was not induced. The exposure of cells in the territories with elevated radiation background leads to genome instability which results in enhanced radiosensitivity. Investigations on the blood lymphocytes of people living in contaminated regions revealed that adaptive response was more significant in children whereas in adults there was slight increase. Acute irradiation serves as a tool revealing the changes that took place in DNA during chronic low level irradiations after Chernobyl disaster. (author).

  5. Large-area irradiated low-level laser effect in a biodegradable nerve guide conduit on neural regeneration of peripheral nerve injury in rats.

    Science.gov (United States)

    Shen, Chiung-Chyi; Yang, Yi-Chin; Liu, Bai-Shuan

    2011-08-01

    This study used a biodegradable composite containing genipin-cross-linked gelatin annexed with β-tricalcium phosphate ceramic particles (genipin-gelatin-tricalcium phosphate, GGT), developed in a previous study, as a nerve guide conduit. The aim of this study was to analyse the influence of a large-area irradiated aluminium-gallium-indium phosphide (AlGaInP) diode laser (660 nm) on the neural regeneration of the transected sciatic nerve after bridging the GGT nerve guide conduit in rats. The animals were divided into two groups: group 1 comprised sham-irradiated controls and group 2 rats underwent low-level laser (LLL) therapy. A compact multi-cluster laser system with 20 AlGaInP laser diodes (output power, 50mW) was applied transcutaneously to the injured peripheral nerve immediately after closing the wound, which was repeated daily for 5 min for 21 consecutive days. Eight weeks after implantation, walking track analysis showed a significantly higher sciatic function index (SFI) score (Pguide conduit in rats. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Effects of low-level laser irradiation on the rate of orthodontic tooth movement and associated pain with self-ligating brackets.

    Science.gov (United States)

    Qamruddin, Irfan; Alam, Mohammad Khursheed; Mahroof, Verda; Fida, Mubassar; Khamis, Mohd Fadhli; Husein, Adam

    2017-11-01

    The aim of this study was to evaluate the effect of low-level laser irradiation applied at 3-week intervals on orthodontic tooth movement and pain associated with orthodontic tooth movement using self-ligating brackets. Twenty-two patients (11 male, 11 female; mean age, 19.8 ± 3.1 years) with Angle Class II Division 1 malocclusion were recruited for this split-mouth clinical trial; they required extraction of maxillary first premolars bilaterally. After leveling and alignment with self-ligating brackets (SmartClip SL3; 3M Unitek, St Paul, Minn), a 150-g force was applied to retract the canines bilaterally using 6-mm nickel-titanium closed-coil springs on 0.019 x 0.025-in stainless steel archwires. A gallium-aluminum-arsenic diode laser (iLas; Biolase, Irvine, Calif) with a wavelength of 940 nm in a continuous mode (energy density, 7.5 J/cm 2 /point; diameter of optical fiber tip, 0.04 cm 2 ) was applied at 5 points buccally and palatally around the canine roots on the experimental side; the other side was designated as the placebo. Laser irradiation was applied at baseline and then repeated after 3 weeks for 2 more consecutive follow-up visits. Questionnaires based on the numeric rating scale were given to the patients to record their pain intensity for 1 week. Impressions were made at each visit before the application of irradiation at baseline and the 3 visits. Models were scanned with a CAD/CAM scanner (Planmeca, Helsinki, Finland). Canine retraction was significantly greater (1.60 ± 0.38 mm) on the experimental side compared with the placebo side (0.79 ± 0.35 mm) (P orthodontic tooth movement and reduce the pain associated with it. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  7. Effects of microcurrent application and 670 nm InGaP low-level laser irradiation on experimental wound healing in healthy and diabetic Wistar rats

    International Nuclear Information System (INIS)

    Neves, L M G; Matheus, R L; Santos, G M T; Esquisatto, M A M; Amaral, M E C; Mendonça, F A S

    2013-01-01

    This study evaluated the effects of microcurrent application and 670 nm InGaP laser irradiation on wound healing in healthy and alloxan diabetic rats. The animals were divided into eight groups: healthy control (HC); diabetic control (DC); healthy treated with microcurrent (HMC); diabetic treated with microcurrent (DMC); healthy irradiated with laser (HL); diabetic irradiated with laser (DL); healthy receiving laser and microcurrent application (HLMC) and diabetic receiving laser and microcurrent application (DLMC). Wound samples were collected on days 2, 6, 10 and 14 of treatment for structural analysis, morphometry, and Western blotting to quantify the expression of TGF-β1 and VEGF. Comparison of animals receiving laser and microcurrent therapy showed a reduction in the number of inflammatory cells in diabetic animals, as well as an increase of fibroblasts in healthy animals and of newly formed vessels in healthy and diabetic animals. Expression of TGF-β1 was increased on day 6 in all groups, especially diabetic animals. A reduction in the expression of this protein was observed on day 10 in all groups. VEGF expression was higher on day 6 in treated and control diabetic animals when compared to healthy animals. Analysis of VEGF expression in the laser- and microcurrent-treated groups on day 10 showed a decrease in diabetic animals and an increase in healthy animals. In conclusion, laser therapy and microcurrent stimulation exert beneficial effects on wound healing in both healthy and diabetic animals. (paper)

  8. Genetic effects of low-level irradiation

    International Nuclear Information System (INIS)

    Selby, P.B.

    1980-01-01

    Recent estimates of the genetic effects of radiation by two widely recognized committees (BEIR III and UNSCEAR 1977) are based to a large extent on data collected in mice using either the specific-locus method or the approach of empirically determining the nature and extent of radiation-induced genetic damage to the skeleton. Both committees made use of doubling-dose and direct methods of estimating genetic hazard. Their estimates can be applied to assessments of risk resulting from medical irradiation in terms both of risk to the population at large and to the individual

  9. Low Level Laser Therapy for chronic knee joint pain patients.

    Science.gov (United States)

    Nakamura, Takashi; Ebihara, Satoru; Ohkuni, Ikuko; Izukura, Hideaki; Harada, Takashi; Ushigome, Nobuyuki; Ohshiro, Toshio; Musha, Yoshiro; Takahashi, Hiroshi; Tsuchiya, Kazuaki; Kubota, Ayako

    2014-12-27

    Chronic knee joint pain is one of the most frequent complaints which is seen in the outpatient clinic in our medical institute. In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic pain in the shoulder joints, elbow, hand, finger and the lower back. The present study is a report on the effects of LLLT for chronic knee joint pain. Over the past 5 years, 35 subjects visited the outpatient clinic with complaints of chronic knee joint pain caused by the knee osteoarthritis-induced degenerative meniscal tear. They received low level laser therapy. A 1000 mW semi-conductor laser device was used to deliver 20.1 J/cm(2) per point in continuous wave at 830nm, and four points were irradiated per session (1 treatment) twice a week for 4 weeks. A visual analogue scale (VAS) was used to determine the effects of LLLT for the chronic pain and after the end of the treatment regimen a significant improvement was observed (pknee joint range of motion. Discussions with the patients revealed that it was important for them to learn how to avoid postures that would cause them knee pain in everyday life in order to have continuous benefits from the treatment. The present study demonstrated that 830 nm LLLT was an effective form of treatment for chronic knee pain caused by knee osteoarthritis. Patients were advised to undertake training involving gentle flexion and extension of the knee.

  10. The effect of low level laser on anaplastic thyroid cancer

    Science.gov (United States)

    Rhee, Yun-Hee; Moon, Jeon-Hwan; Ahn, Jin-Chul; Chung, Phil-Sang

    2015-02-01

    Low-level laser therapy (LLLT) is a non-thermal phototherapy used in several medical applications, including wound healing, reduction of pain and amelioration of oral mucositis. Nevertheless, the effects of LLLT upon cancer or dysplastic cells have been so far poorly studied. Here we report that the effects of laser irradiation on anaplastic thyroid cancer cells leads to hyperplasia. 650nm of laser diode was performed with a different time interval (0, 15, 30, 60J/cm2 , 25mW) on anaplastic thyroid cancer cell line FRO in vivo. FRO was orthotopically injected into the thyroid gland of nude mice and the irradiation was performed with the same method described previously. After irradiation, the xenograft evaluation was followed for one month. The thyroid tissues from sacrificed mice were undergone to H&E staining and immunohistochemical staining with HIF-1α, Akt, TGF-β1. We found the aggressive proliferation of FRO on thyroid gland with dose dependent. In case of 60 J/ cm2 of energy density, the necrotic bodies were found in a center of the thyroid. The phosphorylation of HIF-1α and Akt was detected in the thyroid gland, which explained the survival signaling of anaplastic cancer cell was turned on the thyroid gland. Furthermore, TGF-β1 expression was decreased after irradiation. In this study, we demonstrated that insufficient energy density irradiation occurred the decreasing of TGF-β1 which corresponding to the phosphorylation of Akt/ HIF-1α. This aggressive proliferation resulted to the hypoxic condition of tissue for angiogenesis. We suggest that LLLT may influence to cancer aggressiveness associated with a decrease in TGF-β1 and increase in Akt/HIF-1α.

  11. The Role of Low-Level Laser in Periodontal Surgeries

    Science.gov (United States)

    Sobouti, Farhad; Khatami, Maziar; Heydari, Mohaddase; Barati, Maryam

    2015-01-01

    Treatment protocols with low-level Laser (also called ‘soft laser therapy) have been used in health care systems for more than three decades. Bearing in mind the suitable sub-cellular absorption and the cellular-vascular impacts, low-level laser may be a treatment of choice for soft tissues. Low-level lasers have played crucial and colorful roles in performing periodontal surgeries. Their anti-inflammatory and painless effects have been variously reported in in-vitro studies. In this present review article, searches have been made in Pub Med, Google Scholar, and Science Direct, focusing on the studies which included low-level lasers, flap-periodontal surgeries, gingivectomy, and periodontal graft. The present study has sought to review the cellular impacts of low-level lasers and its role on reducing pain and inflammation following soft tissue surgical treatments. PMID:25987968

  12. Low level diode laser accelerates wound healing.

    Science.gov (United States)

    Dawood, Munqith S; Salman, Saif Dawood

    2013-05-01

    The effect of wound illumination time by pulsed diode laser on the wound healing process was studied in this paper. For this purpose, the original electronic drive circuit of a 650-nm wavelength CW diode laser was reconstructed to give pulsed output laser of 50 % duty cycle and 1 MHz pulse repetition frequency. Twenty male mice, 3 months old were used to follow up the laser photobiostimulation effect on the wound healing progress. They were subdivided into two groups and then the wounds were made on the bilateral back sides of each mouse. Two sessions of pulsed laser therapy were carried along 15 days. Each mice group wounds were illuminated by this pulsed laser for 12 or 18 min per session during these 12 days. The results of this study were compared with the results of our previous wound healing therapy study by using the same type of laser. The mice wounds in that study received only 5 min of illumination time therapy in the first and second days of healing process. In this study, we found that the wounds, which were illuminated for 12 min/session healed in about 3 days earlier than those which were illuminated for 18 min/session. Both of them were healed earlier in about 10-11 days than the control group did.

  13. Only lasers can be used for low level laser therapy.

    Science.gov (United States)

    Moskvin, Sergey Vladimirovich

    2017-12-01

    The question of lasers' exclusivity, as well as the degree of influence of special properties of low-intensity laser illumination (LILI), such as coherence, polarity and monochromaticity, on the effectiveness of low level laser therapy (LLLT) continues to cause arguments. The study analyzes publications from 1973 to 2016, in which laser and conventional light sources are compared, and the following conclusions are drawn. First, there are a lot of publications with incorrect comparison or unfounded statements. Secondly, other sources of light are often meant by LILI without any justification. Thirdly, all studies, in which the comparison is carried out correctly and close parameters of the impact and the model are used, have a firm conclusion that laser light is much more effective. Fourthly, it is uniquely identified that the most important parameter that determines the efficiency of lasers is monochromaticity, i.e., a much narrower spectral width than for all other light sources. Only laser light sources can be used for LLLT! © Author(s) 2017. This article is published with open access by China Medical University.

  14. Effect of Low Level Laser Irradiation at Wavelengths 488 and 515 nm on Glutamate Neurotransmitter in Mitochondria of Visual Brain Cortex in Albino Rat

    International Nuclear Information System (INIS)

    Omran, M.F.; El-Ahdal, M.A.; El-Kady, M.H.; Yousri, R.M.

    2004-01-01

    The presence of glutamate in the visual cortex and mitochondria could be used as a measure for the argon laser effect having wavelengths 488 and 515 nm, on the mitochondria. A comparative response for the bound and free glutamate was found. Irradiation with different energies 0.2, 0.5 and 1.0 J for both wavelengths were accomplished. This study makes us to recommend the advantage of using argon laser having wavelength 515 nm to enhance the blocking of glutamate and hence the reduction of brain toxicity. Most of the energy required for cellular functions comes from mitochondria (Shepherd, 1994). Glutamate, which is present in central nervous system at very high level is essential for brain intermediary metabolism (Frazer et al., 1994; Meldrum et al., 2000 and Blumcke et al., 2000). Glutamate is enriched in synaptic vesicles, the subcellular organelles, which are associated with the storage and release of neurotransmitters. Also, biochemical evidence for glutamate as neurotransmitter in fibers from the visual cortex to the subcortical visual relay nuclei has been indicated (Fose and Fonnum, 1987 and George, 1998)

  15. Effects of low-level chronic irradiation on aquatic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Etoh, H. (National Inst. of Radiological Sciences, Chiba (Japan))

    1980-10-01

    Effects of continual irradiation for a long term on fishes and aquatic invertebrates were outlined. Effects of low-level chronic irradiation on aquatic organisms were less than acute effects induced when the same dose was irradiated once. The radiosensitivity of the genital organ to continual irradiation was high. There was a difference in radiosensitivity of the genital organ between female and male, and the degree of the difference varied according to kinds of animals. In an experiment on continual irradiation of adult killifishes, ova recovered from radiation damage, but spermatozoa did not recover. Incubation rates of eggs obtained from aquatic organisms which lived in water where radioactive sewage flowed into decreased significantly, and the frequency of reverse position of salivary gland chromosomes which were peculiar to exposed organisms increased in larvae of Chironomus tentans.

  16. Low level chronic irradiation of salmon. Annual progress report

    International Nuclear Information System (INIS)

    Hershberger, W.K.; Donaldson, L.R.; Bonham, K.; Brannon, E.L.

    1975-01-01

    A question of primary importance in the use of nuclear energy is what effect the effluent from a reactor will have on the aquatic life in the water used for cooling. Of particular concern in the Pacific Northwest are the effects of chronic irradiation on salmon that use the rivers for spawning and nursery area. The present program was designed in the early days of the atomic era to address this concern, and to provide some insight into the long-term consequences of exposure of fish to chronic, low levels of irradiation. The experimental techniques are described and data are summarized on irradiation effects on the entire life cycle of the chinook salmon. Also, long-term effects transmitted to future generations were assessed in F 1 offspring of irradiated parents

  17. Effect of low-level laser stimulation on EEG.

    Science.gov (United States)

    Wu, Jih-Huah; Chang, Wen-Dien; Hsieh, Chang-Wei; Jiang, Joe-Air; Fang, Wei; Shan, Yi-Chia; Chang, Yang-Chyuan

    2012-01-01

    Conventional laser stimulation at the acupoint can induce significant brain activation, and the activation is theoretically conveyed by the sensory afferents. Whether the insensible low-level Laser stimulation outside the acupoint could also evoke electroencephalographic (EEG) changes is not known. We designed a low-level laser array stimulator (6 pcs laser diode, wavelength 830 nm, output power 7 mW, and operation frequency 10 Hz) to deliver insensible laser stimulations to the palm. EEG activities before, during, and after the laser stimulation were collected. The amplitude powers of each EEG frequency band were analyzed. We found that the low-level laser stimulation was able to increase the power of alpha rhythms and theta waves, mainly in the posterior head regions. These effects lasted at least 15 minutes after cessation of the laser stimulation. The amplitude power of beta activities in the anterior head regions decreased after laser stimulation. We thought these EEG changes comparable to those in meditation.

  18. Effect of Low-Level Laser Stimulation on EEG

    Directory of Open Access Journals (Sweden)

    Jih-Huah Wu

    2012-01-01

    Full Text Available Conventional laser stimulation at the acupoint can induce significant brain activation, and the activation is theoretically conveyed by the sensory afferents. Whether the insensible low-level Laser stimulation outside the acupoint could also evoke electroencephalographic (EEG changes is not known. We designed a low-level laser array stimulator (6 pcs laser diode, wavelength 830 nm, output power 7 mW, and operation frequency 10 Hz to deliver insensible laser stimulations to the palm. EEG activities before, during, and after the laser stimulation were collected. The amplitude powers of each EEG frequency band were analyzed. We found that the low-level laser stimulation was able to increase the power of alpha rhythms and theta waves, mainly in the posterior head regions. These effects lasted at least 15 minutes after cessation of the laser stimulation. The amplitude power of beta activities in the anterior head regions decreased after laser stimulation. We thought these EEG changes comparable to those in meditation.

  19. The effects of low-level laser on muscle damage caused by Bothrops neuwiedi venom

    Directory of Open Access Journals (Sweden)

    DM Dourado

    2008-01-01

    Full Text Available The present study aimed to assess the effects of low-level laser (660 nm on myonecrosis caused by the insertion of Bothrops neuwiedi venom in the gastrocnemius muscle of rats. Male Wistar rats were divided into three groups (n = 24 each: Group S (0.9% saline solution; Group V (venom and Group VLLL (venom plus low-level laser. These categories were subdivided into four additional groups (n = 6 based on the euthanasia timing (3 hours, 24 hours, 3 days and 7 days. The groups V and VLLL were inoculated with 100 µL of concentrated venom (40 µg/mL in the gastrocnemius muscle. The muscle was irradiated using a gallium-aluminum-arsenide laser (GaAlAs at 35 mW power and 4 J/cm² energy density for 3 hours, 24 hours, 3 days or 7 days after venom inoculation. To evaluate the myotoxic activity of the venom, CK activity was measured and the muscle was histologically analyzed. The low-level laser reduced venom-induced CK activity in the groups euthanized at 3 hours, 24 hours and 3 days (p < 0.0001. Histological analysis revealed that low-level laser reduced neutrophilic inflammation as well as myofibrillar edema, hemorrhage and myonecrosis following B. neuwiedi envenomation. These results suggest that low-level laser can be useful as an adjunct therapy following B. neuwiedi envenomation.

  20. The effects of low-level laser on muscle damage caused by Bothrops neuwiedi venom

    Energy Technology Data Exchange (ETDEWEB)

    Dourado, D.M.; Matias, R.; Almeida, M.F.; Paula, K.R. de; Carvalho, P.T.C. [University for the Development of the State and of the Region of Pantanal (UNIDERP), Campo Grande, MS (Brazil). Lab. of Experimental Histopathology]. E-mail: ccfi@uniderp.br; Vieira, R.P. [University of Sao Paulo (USP), SP (Brazil). School of Medicine. Dept. of Pathology and Physical Therapy; Oliveira, L.V.F. [Nove de Julho University (UNINOVE), Sao Paulo, SP (Brazil). Masters Program in Rehabilitation Sciences

    2008-07-01

    The present study aimed to assess the effects of low-level laser (660 nm) on myonecrosis caused by the insertion of Bothrops neuwiedi venom in the gastrocnemius muscle of rats. Male Wistar rats were divided into three groups (n = 24 each): Group S (0.9% saline solution); Group V (venom) and Group VLLL (venom plus low-level laser). These categories were subdivided into four additional groups (n = 6) based on the euthanasia timing (3 hours, 24 hours, 3 days and 7 days). The groups V and VLLL were inoculated with 100 {mu}L of concentrated venom (40 {mu}g/mL) in the gastrocnemius muscle. The muscle was irradiated using a gallium-aluminum-arsenide laser (GaAlAs) at 35 mW power and 4 J/cm{sup 2} energy density for 3 hours, 24 hours, 3 days or 7 days after venom inoculation. To evaluate the myotoxic activity of the venom, CK activity was measured and the muscle was histologically analyzed. The low-level laser reduced venom-induced CK activity in the groups euthanized at 3 hours, 24 hours and 3 days (p < 0.0001). Histological analysis revealed that low-level laser reduced neutrophilic inflammation as well as myofibrillar edema, hemorrhage and myonecrosis following B. neuwiedi envenomation. These results suggest that low-level laser can be useful as an adjunct therapy following B. neuwiedi envenomation. (author)

  1. The effects of low-level laser on muscle damage caused by Bothrops neuwiedi venom

    International Nuclear Information System (INIS)

    Dourado, D.M.; Matias, R.; Almeida, M.F.; Paula, K.R. de; Carvalho, P.T.C.; Vieira, R.P.; Oliveira, L.V.F.

    2008-01-01

    The present study aimed to assess the effects of low-level laser (660 nm) on myonecrosis caused by the insertion of Bothrops neuwiedi venom in the gastrocnemius muscle of rats. Male Wistar rats were divided into three groups (n = 24 each): Group S (0.9% saline solution); Group V (venom) and Group VLLL (venom plus low-level laser). These categories were subdivided into four additional groups (n = 6) based on the euthanasia timing (3 hours, 24 hours, 3 days and 7 days). The groups V and VLLL were inoculated with 100 μL of concentrated venom (40 μg/mL) in the gastrocnemius muscle. The muscle was irradiated using a gallium-aluminum-arsenide laser (GaAlAs) at 35 mW power and 4 J/cm 2 energy density for 3 hours, 24 hours, 3 days or 7 days after venom inoculation. To evaluate the myotoxic activity of the venom, CK activity was measured and the muscle was histologically analyzed. The low-level laser reduced venom-induced CK activity in the groups euthanized at 3 hours, 24 hours and 3 days (p < 0.0001). Histological analysis revealed that low-level laser reduced neutrophilic inflammation as well as myofibrillar edema, hemorrhage and myonecrosis following B. neuwiedi envenomation. These results suggest that low-level laser can be useful as an adjunct therapy following B. neuwiedi envenomation. (author)

  2. Effectiveness of low level laser therapy for treating male infertility

    Science.gov (United States)

    Vladimirovich Moskvin, Sergey; Ivanovich Apolikhin, Oleg

    2018-01-01

    In half of the cases, the infertility of the couple is due to the disorder of the male fertility. The leading factors that cause male infertility are urogenital infections, disorders of the immune system, testicular and prostate pathology, as well as endocrine disorders. Low level laser therapy (LLLT) is a very effective physical therapy method, used in many areas of medicine, including obstetrics and gynaecology, andrology and urology; and it is recommended as an integral part of the complex treatment of infertility. The literature review showed that LLLT is beneficial in treating male infertility. Laser can significantly improve the survival, motility and speed of movement of spermatozoa. Laser therapy of patients with prostatitis and vesiculitis can eliminate infiltrative-exudative changes, improve reproductive and copulatory functions. Local illumination of red (635 nm) and infrared (904 nm) spectra should be combined with intravenous laser blood illumination (ILBI) of red (635 nm) and ultraviolet (UV) (365 nm) spectra. PMID:29806585

  3. Effect of single-dose low-level helium-neon laser irradiation on orthodontic pain: a split-mouth single-blind placebo-controlled randomized clinical trial.

    Science.gov (United States)

    Sobouti, Farhad; Khatami, Maziar; Chiniforush, Nasim; Rakhshan, Vahid; Shariati, Mahsa

    2015-01-01

    Pain is the most common complication of orthodontic treatment. Low-level laser therapy (LLLT) has been suggested as a new analgesic treatment free of the adverse effects of analgesic medications. However, it is not studied thoroughly, and the available studies are quite controversial. Moreover, helium neon (He-Ne) laser has not been assessed before. This split-mouth placebo-controlled randomized clinical trial was performed on 16 male and 14 female orthodontic patients requiring bilateral upper canine retraction. The study was performed at a private clinic in Sari, Iran, in 2014. It was single blind: patients, orthodontist, and personnel were blinded of the allocations, but the laser operator (periodontist) was not blinded. Once canine retractor was activated, a randomly selected maxillary quarter received a single dose of He-Ne laser irradiation (632.8 nm, 10 mw, 6 j/cm(2) density). The other quarter served as the placebo side, treated by the same device but powered off. In the first, second, fourth, and seventh days, blinded patients rated their pain sensed on each side at home using visual analog scale (VAS) questionnaires. There was no harm identified during or after the study. Pain changes were analyzed using two- and one-way repeated-measures ANOVA, Bonferroni, and t-test (α = 0.01, β > 0.99). This trial was not registered. It was self-funded by the authors. Sixteen males and 11 females remained in the study (aged 12-21). Average pain scores sensed in all 4 intervals on control and laser sides were 4.06 ± 2.85 and 2.35 ± 1.77, respectively (t-test P < 0.0001). One-way ANOVA showed significant pain declines over time, in each group (P < 0.0001). Two-way ANOVA showed significant effects for LLLT (P < 0.0001) and time (P = <0.0001). Single-dose He-Ne laser therapy might reduce orthodontic pain caused by retracting maxillary canines.

  4. Expression of DNA repair genes in burned skin exposed to low-level red laser.

    Science.gov (United States)

    Trajano, Eduardo Tavares Lima; Mencalha, Andre Luiz; Monte-Alto-Costa, Andréa; Pôrto, Luís Cristóvão; de Souza da Fonseca, Adenilson

    2014-11-01

    Although red laser lights lie in the region of non-ionizing radiations in the electromagnetic spectrum, there are doubts whether absorption of these radiations causes lesions in the DNA molecule. Our aim was to investigate the expression of the genes involved with base excision and nucleotide excision repair pathways in skin tissue submitted to burn injury and exposed to low-level red laser. Wistar rats were divided as follows: control group-rats burned and not irradiated, laser group-rats burned and irradiated 1 day after injury for five consecutive days, and later laser group-rats injured and treated 4 days after injury for five consecutive days. Irradiation was performed according to a clinical protocol (20 J/cm(2), 100 mW, continuous wave emission mode). The animals were sacrificed on day 10, and scarred tissue samples were withdrawn for total RNA extraction, complementary DNA (cDNA) synthesis, and evaluation of gene expression by quantitative polymerase chain reaction. Low-level red laser exposure (1) reduces the expression of APE1 messenger (mRNA), (2) increases the expression of OGG1 mRNA, (3) reduces the expression of XPC mRNA, and (4) increases the expression of XPA mRNA both in laser and later laser groups. Red laser exposure at therapeutic fluences alters the expression of genes related to base excision and nucleotide excision pathways of DNA repair during wound healing of burned skin.

  5. Effect of low-level laser-treated mesenchymal stem cells on myocardial infarction.

    Science.gov (United States)

    El Gammal, Zaynab H; Zaher, Amr M; El-Badri, Nagwa

    2017-09-01

    Cardiovascular disease is the leading cause of death worldwide. Although cardiac transplantation is considered the most effective therapy for end-stage cardiac diseases, it is limited by the availability of matching donors and the complications of the immune suppressive regimen used to prevent graft rejection. Application of stem cell therapy in experimental animal models was shown to reverse cardiac remodeling, attenuate cardiac fibrosis, improve heart functions, and stimulate angiogenesis. The efficacy of stem cell therapy can be amplified by low-level laser radiation. It is well established that the bio-stimulatory effect of low-level laser is influenced by the following parameters: wavelength, power density, duration, energy density, delivery time, and the type of irradiated target. In this review, we evaluate the available experimental data on treatment of myocardial infarction using low-level laser. Eligible papers were characterized as in vivo experimental studies that evaluated the use of low-level laser therapy on stem cells in order to attenuate myocardial infarction. The following descriptors were used separately and in combination: laser therapy, low-level laser, low-power laser, stem cell, and myocardial infarction. The assessed low-level laser parameters were wavelength (635-804 nm), power density (6-50 mW/cm 2 ), duration (20-150 s), energy density (0.96-1 J/cm 2 ), delivery time (20 min-3 weeks after myocardial infarction), and the type of irradiated target (bone marrow or in vitro-cultured bone marrow mesenchymal stem cells). The analysis focused on the cardioprotective effect of this form of therapy, the attenuation of scar tissue, and the enhancement of angiogenesis as primary targets. Other effects such as cell survival, cell differentiation, and homing are also included. Among the evaluated protocols using different parameters, the best outcome for treating myocardial infarction was achieved by treating the bone marrow by one dose of low-level

  6. Effect of interstitial low level laser stimulation in skin density

    Science.gov (United States)

    Jang, Seulki; Ha, Myungjin; Lee, Sangyeob; Yu, Sungkon; Park, Jihoon; Radfar, Edalat; Hwang, Dong Hyun; Lee, Han A.; Kim, Hansung; Jung, Byungjo

    2016-03-01

    As the interest in skin was increased, number of studies on skin care also have been increased. The reduction of skin density is one of the symptoms of skin aging. It reduces elasticity of skin and becomes the reason of wrinkle formation. Low level laser therapy (LLLT) has been suggested as one of the effective therapeutic methods for skin aging as in hasten to change skin density. This study presents the effect of a minimally invasive laser needle system (MILNS) (wavelength: 660nm, power: 20mW) in skin density. Rabbits were divided into three groups. Group 1 didn't receive any laser stimulation as a control group. Group 2 and 3 as test groups were exposed to MILNS with energy of 8J and 6J on rabbits' dorsal side once a week, respectively. Skin density of rabbits was measured every 12 hours by using an ultrasound skin scanner.

  7. Low-level microwave irradiation and central cholinergic systems

    International Nuclear Information System (INIS)

    Lai, H.; Carino, M.A.; Horita, A.; Guy, A.W.

    1989-01-01

    Our previous research showed that 45 min of exposure to low-level, pulsed microwaves (2450-MHz, 2-microseconds pulses, 500 pps, whole-body average specific absorption rate 0.6 W/kg) decreased sodium-dependent high-affinity choline uptake in the frontal cortex and hippocampus of the rat. The effects of microwaves on central cholinergic systems were further investigated in this study. Increases in choline uptake activity in the frontal cortex, hippocampus, and hypothalamus were observed after 20 min of acute microwave exposure, and tolerance to the effect of microwaves developed in the hypothalamus, but not in the frontal cortex and hippocampus, of rats subjected to ten daily 20-min exposure sessions. Furthermore, the effects of acute microwave irradiation on central choline uptake could be blocked by pretreating the animals before exposure with the narcotic antagonist naltrexone. In another series of experiments, rats were exposed to microwaves in ten daily sessions of either 20 or 45 min, and muscarinic cholinergic receptors in different regions of the brain were studied by 3H-QNB binding assay. Decreases in concentration of receptors occurred in the frontal cortex and hippocampus of rats subjected to ten 20-min microwave exposure sessions, whereas increase in receptor concentration occurred in the hippocampus of animals exposed to ten 45-min sessions. This study also investigated the effects of microwave exposure on learning in the radial-arm maze. Rats were trained in the maze to obtain food reinforcements immediately after 20 or 45 min of microwave exposure

  8. Low-level lasers affect uncoupling protein gene expression in skin and skeletal muscle tissues

    International Nuclear Information System (INIS)

    Canuto, K S; Sergio, L P S; Mencalha, A L; Fonseca, A S; Paoli, F

    2016-01-01

    Wavelength, frequency, power, fluence, and emission mode determine the photophysical, photochemical, and photobiological responses of biological tissues to low-level lasers. Free radicals are involved in these responses acting as second messengers in intracellular signaling processes. Irradiated cells present defenses against these chemical species to avoid unwanted effects, such as uncoupling proteins (UCPs), which are part of protective mechanisms and minimize the effects of free radical generation in mitochondria. In this work UCP2 and UCP3 mRNA gene relative expression in the skin and skeletal muscle tissues of Wistar rats exposed to low-level red and infrared lasers was evaluated. Samples of the skin and skeletal muscle tissue of Wistar rats exposed to low-level red and infrared lasers were withdrawn for total RNA extraction, cDNA synthesis, and the evaluation of gene expression by quantitative polymerase chain reaction. UCP2 and UCP3 mRNA expression was differently altered in skin and skeletal muscle tissues exposed to lasers in a wavelength-dependent effect, with the UCP3 mRNA expression dose-dependent. Alteration on UCP gene expression could be part of the biostimulation effect and is necessary to make cells exposed to red and infrared low-level lasers more resistant or capable of adapting in damaged tissues or diseases. (paper)

  9. Effects of low-level laser therapy on wound healing

    Directory of Open Access Journals (Sweden)

    Fabiana do Socorro da Silva Dias Andrade

    Full Text Available OBJECTIVE: To gather and clarify the actual effects of low-level laser therapy on wound healing and its most effective ways of application in human and veterinary medicine.METHODS: We searched original articles published in journals between the years 2000 and 2011, in Spanish, English, French and Portuguese languages, belonging to the following databases: Lilacs, Medline, PubMed and Bireme; Tey should contain the methodological description of the experimental design and parameters used.RESULTS: doses ranging from 3 to 6 J/cm2 appear to be more effective and doses 10 above J/cm2 are associated with deleterious effects. The wavelengths ranging from 632.8 to 1000 nm remain as those that provide more satisfactory results in the wound healing process.CONCLUSION: Low-level laser can be safely applied to accelerate the resolution of cutaneous wounds, although this fact is closely related to the election of parameters such as dose, time of exposure and wavelength.

  10. Effect of low-level pulsed laser 890-nm on lumbar spondylolisthesis: a case report

    Science.gov (United States)

    Mortazavi, Seyed M. J.; Afsharpad, Mitra; Djavid, Gholam-reza E.

    2002-10-01

    Objective: Evaluating the effectiveness of low-level laser therapy (LLLT) in alleviating the symptoms of lumbar spondylolisthesis. Materials and Methods: Laser was irradiated for 2 mm at six symmetric points along the lumbosacral spine and 5 points along the referred point ofpain, six times a week for 2 weeks (890 nm; 8 J/cm2; pulsed at 1500 Hz). Perception of benefit, level of function was assessed by the Oswestry disability index, lumbar mobility range of motion and low back pain intensity. Results and Discussion: Results showed a complete reduction in pain and improvement in function in the patient. This case report suggests that low-level laser therapy (LLLT) could play a role in conservative management of low-grade lumbar spondylolisthesis.

  11. Low-level laser/light therapy for androgenetic alopecia.

    Science.gov (United States)

    Gupta, Aditya K; Lyons, Danika C A; Abramovits, William

    2014-01-01

    Androgenetic alopecia (AGA) is a persistent and pervasive condition that affects men worldwide. Some common treatment options for AGA include hair prosthetics, oral and topical medications, and surgical hair restoration (SHR). Pharmaceutical and SHR treatments are associated with limitations including adverse side effects and significant financial burden. Low-level laser or light (LLL) devices offer alternative treatment options that are not typically associated with adverse side effects or significant costs. There are clinic- and home-based LLL devices. One home-based laser comb device has set a standard for others; however, this device requires time devoted to carefully moving the comb through the hair to allow laser penetration to the scalp. A novel helmet-like LLL device for hair growth has proven effective in preliminary trials and allows for hands-free use. Regardless, there are few clinical trials that have been conducted regarding LLL devices for AGA and results are mixed. Further research is required to establish the true efficacy of these devices for hair growth in comparison to existing alternative therapies.

  12. Low-level laser therapy to treat fibromyalgia.

    Science.gov (United States)

    Ruaro, J A; Fréz, A R; Ruaro, M B; Nicolau, R A

    2014-11-01

    Several clinical treatments have been proposed to manage symptoms of fibromyalgia. Low-level laser therapy (LLLT) may be a useful tool to treat this dysfunction. The aim of this study was to evaluate the effects of LLLT in patients with fibromyalgia. A placebo-controlled, randomized clinical trial was carried out with 20 patients divided randomly into either an LLLT group (n = 10) or a placebo group (n = 10). The LLLT group was treated with a GaAlAs laser (670 nm, 4 J/cm(2) on 18 tender points) three times a week over 4 weeks. Before and after treatment, patients were evaluated with the Fibromyalgia Impact Questionnaire (FIQ), McGill Pain Questionnaire, and visual analog scale (VAS). Data from the FIQ and McGill questionnaire for the treated and control groups were analyzed by paired t tests, and Wilcoxon tests were used to analyze data from the VAS. After LLLT or sham treatment, the number of tender points was significantly reduced in both groups (LLLT, p fibromyalgia symptoms showed significant improvements after LLLT compared to placebo (FIQ, p = 0.0003; McGill, p = 0.0078; and VAS, p = 0.0020). LLLT provided relief from fibromyalgia symptoms in patients and should be further investigated as a therapeutic tool for management in fibromyalgia.

  13. Low level laser therapy for patients with cervical disk hernia.

    Science.gov (United States)

    Takahashi, Hiroshi; Okuni, Ikuko; Ushigome, Nobuyuki; Harada, Takashi; Tsuruoka, Hiroshi; Ohshiro, Toshio; Sekiguchi, Masayuki; Musya, Yoshiro

    2012-09-30

    In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic shoulder joint pain, elbow, hand and finger pain, and low back pain. The present study is a report on the effects of LLLT for chronic neck pain. Over a 3 year period, 26 rehabilitation department outpatients with chronic neck pain, diagnosed as being caused by cervical disk hernia, underwent treatment applied to the painful area with a 1000 mW semi-conductor laser device delivering at 830 nm in continuous wave, 20.1 J/cm(2)/point, and three shots were given per session (1 treatment) with twice a week for 4 weeks. 1. A visual analogue scale (VAS) was used to determine the effects of LLLT for chronic pain and after the end of the treatment regimen a significant improvement was observed (pcervical spine range of motion were observed. 3. Discussions with the patients revealed that in order to receive continued benefits from treatment, it was important for them to be taught how to avoid postures that would cause them neck pain in everyday life. The present study demonstrates that LLLT was an effective form of treatment for neck and back pain caused by cervical disk hernia, reinforced by postural training.

  14. Effects of polarization in low-level laser therapy of spinal cord injury in rats

    Science.gov (United States)

    Ando, Takahiro; Sato, Shunichi; Kobayashi, Hiroaki; Nawashiro, Hiroshi; Ashida, Hiroshi; Hamblin, Michael R.; Obara, Minoru

    2012-03-01

    Low-level laser therapy (LLLT) is a promising approach to treat the spinal cord injury (SCI). Since nerve fibers have optical anisotropy, propagation of light in the spinal tissue might be affected by its polarization direction. However, the effect of polarization on the efficacy of LLLT has not been elucidated. In the present study, we investigated the effect of polarization on the efficacy of near-infrared LLLT for SCI. Rat spinal cord was injured with a weight-drop device. The lesion site was irradiated with an 808-nm diode laser beam that was transmitted through a polarizing filter immediately after injury and daily for five consecutive days. The laser power at the injured spinal cord surface was 25 mW, and the dosage per day was 9.6 J/cm2 (spot diameter, 2 cm; irradiation duration, 1200 s). Functional recovery was assessed daily by an open-field test. The results showed that the functional scores of the SCI rats that were treated with 808-nm laser irradiation were significantly higher than those of the SCI alone group (Group 1) from day 5 after injury, regardless of the polarization direction. Importantly, as compared to the locomotive function of the SCI rats that were treated with the perpendicularly-polarized laser parallel to the spinal column (Group 2), that of the SCI rats that were irradiated with the linearly aligned polarization (Group 3) was significantly improved from day 10 after injury. In addition, the ATP contents in the injured spinal tissue of Group 3, which were measured immediately after laser irradiation, were moderately higher than those of Group 2. These observations are attributable to the deeper penetration of the parallelpolarized light in the anisotropic spinal tissue, suggesting that polarization direction significantly affects the efficacy of LLLT for SCI.

  15. Effects of chronic low-level irradiation on Gambusia affinis

    International Nuclear Information System (INIS)

    Blaylock, B.G.; Frank, M.L.

    1979-01-01

    Since 1944, White Oak Lake (WOL), located on the Oak Ridge Reservation, has served as a final settling basin for low-level radioactive effluents from the Oak Ridge National Laboratory. Organisms inhabiting the lake have been exposed for many generations to chronic low-level radiation significantly higher than background. During the past decade, studies on Gambusia affinis from WOL have been carried out to relate estimated radiation doses to effects on the fitness of the Gambusia population. Results of studies on fecundity, temperature tolerance, and embryonic mortality have led to the conclusion that the Gambusia population in White Oak Lake has an increased frequency of deleterious and recessive lethal genes which may be attributed to the radiation exposure history. The frequency of nonviable embryos from WOL Gambusia did not change significantly from 1966 to 1978; however, it was still significantly greater than that of a control population. In July 1977, Gambusia from a control population were stocked into a 0.45-ha pond which had served as a low-level waste settling basin. The beta and gamma dose rate in this pond averaged from 37 rad/yr at the water surface, 394 rad/yr at mid-depth, and 1150 rad/yr at the surface of the sediments. Preliminary results from samples taken in August 1978 showed that although the frequency of nonviable embryos increased, the frequency was not significantly greater than that of the control parent population. Additional sampling of future generations of Gambusia in this pond will determine whether the frequency of nonviable embryos increases as succeeding generations are exposed to dose rates that are higher than the dose rates in WOL

  16. Assumed genetic effects of low level irradiation on man

    International Nuclear Information System (INIS)

    Dutrillaux, B.

    1976-01-01

    The significance of human genetic pathology is stated and a study is made of the assumed effect of low level ionizing radiations. The theoretical notions thus derived are compared to experimental data which are poor. A quick survey of the literature shows that is has not yet been possible to establish a direct relationship between an increase of exposure and any genetic effect on man. However, this must not lead to conclude on the innoxiousness of radiation but rather shows how such analyses are difficult in as much as the effect investigated is necessarily low [fr

  17. Efficacy of low level laser therapy in the treatment of burning mouth syndrome: A systematic review.

    Science.gov (United States)

    Al-Maweri, Sadeq Ali; Javed, Fawad; Kalakonda, Butchibabu; AlAizari, Nader A; Al-Soneidar, Walid; Al-Akwa, Ameen

    2017-03-01

    Burning mouth syndrome (BMS) is a chronic pain condition with indefinite cure, predominantly affecting post-menopausal women. The aim of this study was to systematically review the efficacy of low level laser therapy in the treatment of burning mouth syndrome (BMS). PubMed, Embase and Scopus were searched from date of inception till and including October 2016 using various combinations of the following keywords: burning mouth syndrome, BMS, stomatodynia, laser therapy, laser treatment and phototherapy. The inclusion criteria were: Prospective, retrospective and case series studies. Letter to editors, reviews, experimental studies, studies that were not published in English, theses, monographs, and abstracts presented in scientific events were excluded. Due to heterogeneity of data no statistical analyses were performed. Ten clinical studies fulfilled the eligibility criteria, five of which were randomized clinical trials. In these studies, the laser wavelengths, power output and duration of irradiation ranged between 630-980nm, 20-300mW, 10s-15min, respectively. Most of studies reported laser to be an effective therapy strategy for management of BMS. Majority of the studies showed that laser therapy seemed to be effective in reducing pain in BMS patients. However, due to the varied methodologies and substantial variations in laser parameters among these studies, more clinical trials are required to ascertain the efficacy of laser for treating BMS. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. The Dose That Works: Low Level Laser Treatment of Tendinopathy

    International Nuclear Information System (INIS)

    Tumilty, Steve; Munn, Joanne; David Baxter, G.; McDonough, Suzanne; Hurley, Deirdre A.; Basford, Jeffrey R.

    2010-01-01

    Background: Low Level Laser Therapy (LLLT) is used in the treatment of tendon injuries. However, the clinical effectiveness of this modality remains controversial with limited agreement on the most efficacious dosage and parameter choices. Purpose: To assess the clinical effectiveness of LLLT in the treatment of tendinopathy and the validity of current dosage recommendations for treatment. Method: Medical databases were searched from inception to 1st August 2008. Controlled clinical trials evaluating LLLT as a primary intervention for any tendinopathy were included in the review. Methodological quality was classified using the PEDro scale. Appropriateness of treatment parameters were assessed using established guidelines. Results: Twenty five trials met the inclusion criteria. There was conflicting findings from multiple trials: 12 showed positive effects and 13 were inconclusive or showed no effect. Dosages used in the 12 positive studies support the existence of an effective dosage window that closely resembled current guidelines. Where pooling of data was possible, LLLT showed a positive effect size; in high quality studies of lateral epicondylitis, participants' grip strength was 9.59 Kg higher than the control group; for participants with Achilles tendinopathy, the effect was 13.6 mm less pain on a 100 mm visual analogue scale. Conclusion: This study found conflicting evidence as to the effectiveness of LLLT in the treatment of tendinopathy. However, an effective dosage window emerged showing benefit in the treatment of tendinopathy. Strong evidence exists from the 12 positive studies that positive outcomes are associated with the use of current dosage recommendations for the treatment of tendinopathy.

  19. The Dose That Works: Low Level Laser Treatment of Tendinopathy

    Science.gov (United States)

    Tumilty, Steve; Munn, Joanne; McDonough, Suzanne; Hurley, Deirdre A.; Basford, Jeffrey R.; David Baxter, G.

    2010-05-01

    Background: Low Level Laser Therapy (LLLT) is used in the treatment of tendon injuries. However, the clinical effectiveness of this modality remains controversial with limited agreement on the most efficacious dosage and parameter choices. Purpose: To assess the clinical effectiveness of LLLT in the treatment of tendinopathy and the validity of current dosage recommendations for treatment. Method: Medical databases were searched from inception to 1st August 2008. Controlled clinical trials evaluating LLLT as a primary intervention for any tendinopathy were included in the review. Methodological quality was classified using the PEDro scale. Appropriateness of treatment parameters were assessed using established guidelines. Results: Twenty five trials met the inclusion criteria. There was conflicting findings from multiple trials: 12 showed positive effects and 13 were inconclusive or showed no effect. Dosages used in the 12 positive studies support the existence of an effective dosage window that closely resembled current guidelines. Where pooling of data was possible, LLLT showed a positive effect size; in high quality studies of lateral epicondylitis, participants' grip strength was 9.59 Kg higher than the control group; for participants with Achilles tendinopathy, the effect was 13.6 mm less pain on a 100 mm visual analogue scale. Conclusion: This study found conflicting evidence as to the effectiveness of LLLT in the treatment of tendinopathy. However, an effective dosage window emerged showing benefit in the treatment of tendinopathy. Strong evidence exists from the 12 positive studies that positive outcomes are associated with the use of current dosage recommendations for the treatment of tendinopathy.

  20. A low-level diode laser therapy reduces the lipopolysaccharide (LPS)-induced periodontal ligament cell inflammation

    International Nuclear Information System (INIS)

    Huang, T H; Chen, C C; Liu, S L; Lu, Y C; Kao, C T

    2014-01-01

    The purpose of this study was to investigate the cytologic effects of inflammatory periodontal ligament cells in vitro after low-level laser therapy. Human periodontal ligament cells were cultured, exposed to lipopolysaccharide and subjected to low-level laser treatment of 5 J cm −2 or 10 J cm −2 using a 920 nm diode laser. A periodontal ligament cell attachment was observed under a microscope, and the cell viability was quantified by a mitochondrial colorimetric assay. Lipopolysaccharide-treated periodontal ligament cells were irradiated with the low-level laser, and the expression levels of several inflammatory markers, iNOS, TNF-α and IL-1, and pErk kinase, were analyzed by reverse transcription polymerase chain reaction and western blot. The data were collected and analyzed by one-way analysis of variance; p < 0.05 indicated a statistically significant difference. The low-level laser treatment of periodontal ligament cells increased their ability to attach and survive. After irradiation, the expression levels of iNOS, TNF-α and IL-1 in lipopolysaccharide-exposed periodontal ligament cells decreased over time (p < 0.05). In periodontal ligament cells, low-level diode laser treatment increased the cells’ proliferative ability and decreased the expression of the examined inflammatory mediators. (letters)

  1. Laboratory methods for evaluating the effect of low level laser ...

    African Journals Online (AJOL)

    The basic tenet of laser therapy is that laser radiation has a wavelength dependent capability to alter cellular behaviour in the absence of significant heating. Low intensity radiation can inhibit as well as stimulate cellular activity. Laser therapy typically involves the delivery of 1-4J/cm 2 to treatments sites with lasers having ...

  2. Is it possible to prevent morbidity on post cardiovascular surgery applying low level laser therapy?

    Science.gov (United States)

    Pinto, Nathali C.; Baptista, Ivany Machado d. C.; Pereira, Mara Helena C.; Serrão, Nelson F.; Pomerantzeff, Pablo M. A.; Chavantes, Maria Cristina

    2014-03-01

    Background and Objective: Complications following cardiovascular surgery incision are common in mediastinitis and wound dehiscence form, a 47% mortality rate remaining. Low Level Laser Therapy (LLLT) has been employed mainly to its effectiveness analgesic and anti-inflammatory actions, aiding the tissue repair process. The aim of this study was to evaluate infrared LLLT onto surgical incision in patients submitted to cardiovascular surgery. Materials and Methods: 40 patients were divided in two groups: Placebo Group (G1) - conventional therapy + "Laser pointer" and Laser Group (G2) - conventional therapy + Infrared Laser irradiation on surgical incision. Diode Laser was employed, C.W. mode, around the surgical wound bed, on immediate Post Operative (PO), 1st PO and 3rd PO with the following parameters: wavelength (λ): 830nm, P=35mW, E=0,75J. Results: G2 didn't present any complication and 5% of patients in G1 developed incision dehiscence and infection. On 7thPO, still a large amount of G1 patients showed pain and unquestionable inflammatory signs surrounding the surgical wound, when compared to G2. Besides, hospital stay in Laser Group was 2 times shorter than in Placebo Group (p-value=0.001). Conclusion: Infrared Laser denoted to be safe and exceptionally valuable tools in preventing morbidities on post cardiovascular surgeries.

  3. Effect of low-level laser therapy on tooth sensitivity induced by in-office bleaching.

    Science.gov (United States)

    Moosavi, Horieh; Arjmand, Nooshin; Ahrari, Farzaneh; Zakeri, Majid; Maleknejad, Fatemeh

    2016-05-01

    This study aimed to investigate the effect of low-level laser therapy (LLLT) on tooth sensitivity induced by in-office bleaching. Sixty-six patients enrolled in this randomized clinical trial. Following the in-office procedure with 40% hydrogen peroxide, the participants were randomly divided into three groups. The patients in group 1 received irradiation from a low-level red laser (LLRL; 660 nm, 200 mW, 15 s, 12 J/cm(2)), whereas participants in group 2 were subjected to a low-level infrared laser (LLIL; 810 nm) under similar conditions as in group 1. In group 3 (placebo), the laser treatment was the same as that in groups 1 and 2, but without energy output. The degree of tooth sensitivity was recorded at 1, 24, and 48 h after bleaching using a visual analog scale (VAS). The change in tooth shade was measured 30 days after tooth whitening. The intensity of tooth sensitivity was not significantly different between groups at 1 h after bleaching (p > 0.05). At 24 h after therapy, pain level was significantly lower in the LLIL group compared to the LLRL and placebo groups (p bleaching, VAS scores in the LLIL and LLRL groups were comparable to each other (p > 0.05) and both were significantly lower than that of the placebo group (p  0.05). LLLT with an infrared diode laser could be recommended as a suitable strategy to reduce the intensity of tooth sensitivity after in-office bleaching.

  4. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial.

    Science.gov (United States)

    Santos, Jaqueline de O; de Oliveira, Sonia M J V; da Silva, Flora M B; Nobre, Moacyr R C; Osava, Ruth H; Riesco, Maria L G

    2012-12-01

    To evaluate the effectiveness of a low-level laser therapy for pain relief in the perineum following episiotomy during childbirth. Laser irradiation is a painless and non-invasive therapy for perineal pain treatment and its effects have been investigated in several studies, with no clear conclusion on its effectiveness. A double-blind randomised controlled clinical trial. One hundred and fourteen women who underwent right mediolateral episiotomies during vaginal birth in an in-hospital birthing centre in São Paulo, Brazil and reported pain ≥ 3 on a numeric scale (0-10) were randomised into three groups of 38 women each: two experimental groups (treated with red and infrared laser) and a control group. The experimental groups were treated with laser applied at three points directly on the episiotomy after suturing in a single session between 6-56 hours postpartum. We used a diode laser with wavelengths of 660 nm (red laser) and 780 nm (infrared laser). The control group participants underwent all laser procedures, excluding the emission of irradiation. The participants and the pain scores evaluator were blinded to the type of intervention. The perineal pain scores were assessed at three time points: before, immediately after and 30 minutes after low-level laser therapy. The comparison of perineal pain between the three groups showed no significant differences in the three evaluations (p = 0.445), indicating that the results obtained in the groups treated with low-level laser therapy were equivalent to the control group. Low-level laser therapy did not decrease the intensity of perineal pain reported by women who underwent right mediolateral episiotomy. The effect of laser in perineal pain relief was not demonstrated in this study. The dosage may not have been sufficient to provide relief from perineal pain after episiotomy during a vaginal birth. © 2012 Blackwell Publishing Ltd.

  5. Biostimulation effects on wheat seeds (Triticum Aestivum L) caused by low level red laser radiation with λ = 660 nm

    International Nuclear Information System (INIS)

    Hernandez, M.; Michtchenko, A.

    2009-01-01

    The principal objective is to study the biostimulation effects caused by a semiconductor low level laser radiation with ? = 660 nm on wheat seeds (Triticum Aestivum L). Seeds were treated before sowing with this laser light source. An increase in the growth of the stem of 12% with respect to control seeds was registered for seeds radiated by an intensity of 15mW/cm 2 and an irradiation time of 60 seconds. (Author)

  6. The disturbances of lipid metabolism regulation after the prenatal low-level irradiation

    International Nuclear Information System (INIS)

    Rogov, Yu.I.; Danil'chik, V.S.; Spivak, L.V.; Rubchenya, I.N.

    2000-01-01

    The objective of this study was to assess the influence of low-level irradiation on lipid metabolism in rats after prenatal exposure. Pregnant rats were irradiated during the period of gestation with the whole final dose 0,5 Gy/rat. The blood lipid fractions were investigated in newborn rats and in 6-month age rats. In irradiated offspring the lipo synthesis processes exceeded lipolysis in comparison with that of the control. The negative consequences of embryo low-level irradiation in the lipid metabolism regulation are discussed in this report. (authors)

  7. Application of low level laser on skin cell lines

    CSIR Research Space (South Africa)

    Ndhundhuma, IM

    2010-01-01

    Full Text Available Lasers have emerged as powerful tools for tissue engineering. To examine cellular growth, and cell to cell interactions, in vitro skin models have been developed combining two major cell types of skin, keratinocytes and fibroblasts. The main...

  8. Evaluation of two protocols for low-level laser application in patients submitted to orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Mariana Marquezan

    2013-02-01

    Full Text Available INTRODUCTION: Different low-level laser (LLL irradiation protocols have been tested to accelerate orthodontic tooth movement (OTM. Nevertheless, divergent results have been obtained. It was suggested that the stimulatory action of low level laser irradiation occurs during the proliferation and differentiation stages of bone cellular precursors, but not during later stages. OBJECTIVE: The purpose of this study was to determine the effect of two protocols of LLL irradiation on experimental tooth movement: One with daily irradiations and another with irradiations during the early stages. METHODS: Thirty-six rats were divided into control groups (CG1, CG2, CG3 and irradiated groups (IrG1, IrG2, IrG3 according to the presence of: experimental tooth movement, laser irradiation, type of laser irradiation protocol and date of euthanasia (3th or 8th day of experiment. At the end of experimental periods, a quantitative evaluation of the amount of OTM was made and the reactions of the periodontium were analyzed by describing cellular and tissue reactions and by counting blood vessels. RESULTS: The amount of OTM revealed no significant differences between groups in the same experimental period (p INTRODUÇÃO: diferentes protocolos de irradiação por laser de baixa potência (LBP têm sido testados para potencializar o movimento ortodôntico; entretanto, há resultados divergentes. Foi sugerido que seu efeito bioestimulador ocorre nas fases de proliferação e diferenciação celular, não agindo em estágios tardios. OBJETIVO: avaliar o efeito de dois protocolos de irradiação do LBP na movimentação ortodôntica: um com irradiações diárias e outro em que irradiações foram realizadas apenas nos períodos iniciais. MÉTODOS: trinta e seis ratos Wistar foram divididos em grupos controles (GC1, GC2 e GC3 e irradiados (GIr1, GIr2 e GIr3, de acordo com a presença de dispositivo ortodôntico, a presença de irradiação, o tipo de protocolo de irradia

  9. Superluminous Devices Versus Low-Level Laser for Temporomandibular Disorders

    Directory of Open Access Journals (Sweden)

    Sveshtarov Vasil

    2018-03-01

    Full Text Available The aim of this study is to compare the pain intensity reduction between the mean radiation doses per session of gallium-aluminum-arsenide (GaAIAs laser with superluminous diodes (SLD in four of the most common pain-related chronic temporomandibular disorders (TMD - local myalgia, myofascial pain, myofascial pain with a referral, and arthralgia. This study was implemented on 124 patients with pain-related temporomandibular disorders according to the DC/TMD criteria. We applied trigger point oriented near-infrared laser (785 nm, 100 s, 8 J/cm2 and SLD cluster sessions (the cluster is composed of 49 SLDs with a combination of visible red (633 nm and infrared (880 nm diodes, 200 mW, 300 s, 8 J/cm2 for the temporomandibular joints and the affected muscles. Patients were evaluated at the start of the treatment, and after the 6th session of combined phototherapy. The pain intensity scores were measured according to the Visual Analogue Scale (VAS. Our results show that the most statistically manifested pain reduction is found for the SLD dose, р = 0,000118, followed by the overall dose (laser plus SLD; р = 0,001031, and the laser dose; р = 0,030942 (ANOVA dispersion analyses. Consequently, it can be concluded that myalgia is better treated through lower doses of red light compared to infrared laser doses because SLDs combine the prooxidative effect of photons with 633 nm wavelength, a large area of exposure, sufficient tissue penetration, and some positive warming thermal impact of the SLD clusters.

  10. Immediate pain relief effect of low level laser therapy for sports injuries: Randomized, double-blind placebo clinical trial.

    Science.gov (United States)

    Takenori, A; Ikuhiro, M; Shogo, U; Hiroe, K; Junji, S; Yasutaka, T; Hiroya, K; Miki, N

    2016-12-01

    To determine the immediate pain relief effect of low-level laser therapy on sports injuries in athletes and degree of pain relief by the therapy. Double-blind, randomized, comparative clinical study. Participants were 32 college athletes with motion pain at a defined site. Participants were randomized into two groups in which the tested or placebo laser therapy was administered to determine pain intensity from painful action before and after laser irradiation, using the Modified Numerical Rating Scale. The post-therapeutic Modified Numerical Rating Scale score was subtracted from the pre-therapeutic Modified Numerical Rating Scale score to determine pain intensity difference, and the rate of pain intensity difference to pre-therapeutic Modified Numerical Rating Scale was calculated as pain relief rate. Low-level laser therapy was effective in 75% of the laser group, whereas it was not effective in the placebo group, indicating a significant difference in favor of the laser group (p<0.001). Pain relief rate was significantly higher in the laser group than in the placebo group (36.94% vs. 8.20%, respectively, p<0.001), with the difference in pain relief rate being 28.74%. Low-level laser therapy provided an immediate pain relief effect, reducing pain by 28.74%. It was effective for pain relief in 75% of participants. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  11. Low Level Laser Therapy for Traumatic Brain Injury

    Science.gov (United States)

    2015-10-01

    Department of Surgery). A project manager was also hired through a joint search between our team and the MGH ED and will replace the role previously... neuromuscular coordination), and Morris water maze (spatial learning and memory). A single exposure of 810 nm laser (18 J/cm2 delivered at 25 mW/cm2...treatments, is not due to Figure 3. Mean NSS ( neuromuscular coordination) scores of mice with moderate TBI receiving different numbers of daily tLLLT

  12. Effect of red and infrared low-level laser therapy in endodontic sealer on subcutaneous tissue

    Science.gov (United States)

    Sivieri-Araujo, G.; Berbert, F. L. C. V.; Ramalho, L. T. O.; Rastelli, A. N. S.; Crisci, F. S.; Bonetti-Filho, I.; Tanomaru-Filho, M.

    2011-12-01

    This study evaluated the reactions of connective tissue after the implant of one endodontic sealer (Endofill) that was irradiated with low-level laser therapy (LLLT). Sixty mice were distributed into three Groups ( n = 20): GI—the tubes filled with Endofill were implanted in the animals and were not irradiated with LLLT; GII—the tubes containing Endofill were implanted in the animals and then irradiated with red LLLT (InGaAlP, λ = 685 nm, P = 35 mW, t = 58 s, D = 72 J/cm2, E = 2 J, Ø = 0.60 mm, continuous mode) and GIII—the tubes with Endofill were implanted and irradiated with infrared LLLT (AsGaAl, λ = 830 nm, P = 50 mW, t = 40 s, D = 70 J/cm2, E = 2 J, Ø = 0.60 mm, continuous wave) both are semiconductor diode laser device. The animals were killed after 7 and 30 days. Series sections of 6 μm thickness were obtained and stained with Hematoxylin-Eosin and Masson Trichrome. The data of the histopathological evaluation were submitted to Kruskal-Wallis and Dunn's tests at 5% significance level. At the 7th day: GI showed the presence of inflammation; GII and GIII reduced inflammation. At 30th day: GI showed low inflammation; GII and GII the absence of inflammation. It was possible show that LLLT reduced the irritating effect promoted by the Endofill, in the period of 7 days ( p > 0.05). The tissue repair occurred in 30 days, regardless of the use of LLLT.

  13. Effect of low-level laser on healing of temporomandibular joint osteoarthritis in rats.

    Directory of Open Access Journals (Sweden)

    Ali Peimani

    2014-06-01

    Full Text Available Temporomandibular disorders (TMD are clinical conditions characterized by pain and sounds of the temporomandibular joint (TMJ. This study was designed to assess the effect of low-level laser therapy (LLLT on healing of osteoarthritis in rats with TMD.Thirty-two male Wistar rats (250-200 g were housed in standard plastic cages. After injection of Complete Freund's adjuvant into the TMJ, rats were randomly divided into two groups of 16 (case and control and anesthetized; then osteoarthritis was induced via intraarticular injection of 50 µl of Complete Freund's adjuvant; into the bilateral TMJs. In the case group, LLLT was done transcutaneously for 10 minutes daily, starting the day after the confirmation of osteoarthritis. Exposure was performed for 10 minutes at the right side of the TMJ with 880 nm low-level laser with 100 mW power and a probe diameter of 0.8 mm. Control rats were not treated with laser.After three days of treatment the grade of cartilage defects, number of inflammatory cells, angiogenesis, number of cell layers and arthritis in rats in the case group were not significantly different compared with controls (P>0.05. After seven days, the grade of cartilage defects, number of inflammatory cells, number of cell layers, and arthritis in the case group improved compared to controls (P<0.05; angiogenesis in both groups was similar.Treatment of TMD with LLLT after 7 days of irradiation with a wavelength of 880 nm was associated with a greater improvement compared to the control group.

  14. The Effect of One Session Low Level Laser Therapy of Extracted Follicular Units on the Outcome of Hair Transplantation

    OpenAIRE

    Tabaie, Seyed Mehdi; Berenji Ardestani, Hoda; Azizjalali, Mir Hadi

    2016-01-01

    Introduction: Photobiostimulation with low level laser (LLL) has been used in medicine for a long time and its effects have been shown in many diseases. Some studies have evaluated the effect of LLL on androgenic alopecia. One of the most important limitations of the use of LLL in the treatment of alopecia is the requirement for multiple sessions, which is hardly accepted by patients. This study was conducted to evaluate the effect of the irradiation of extracted follicular hair units by LLL ...

  15. Evaluation of the efficacy of low-level laser in improving the symptoms of burning mouth syndrome.

    Science.gov (United States)

    Arbabi-Kalati, Fateme; Bakhshani, Nour-Mohammad; Rasti, Maryam

    2015-10-01

    Burning mouth syndrome (BMS) is common conditions that affects menopause women, patients suffer from sever burning sensation. Up to now there is no definitive treatment for this disease. Present study was undertaken to evaluate the efficacy of low-level laser (LLL) in improving the symptoms of burning mouth syndrome. Twenty patients with BMS were enrolled in this study; they were divided in two groups randomly. In the laser group, in each patient, 10 areas on the oral mucosa were selected and underwent LLL irradiation at a wavelength of 630 nm, and a power of 30 mW for 10 seconds twice a week for 4 weeks. In the placebo group, silent/off laser therapy was carried out during the same period in the same areas. Burning sensation and quality of life were evaluated. Burning sensation severity and quality of life in the two groups after intervention were different significant statistically, (p= 0.004, p= 0.01 respectively) .Patients in laser group had better results. It can be concluded that low level laser might decrease the intensity of burning mouth syndrome. Pain, low-level laser, burning mouth syndrome, oral mucosa.

  16. Evidence from mammalian studies on genetic effects of low level irradiation

    International Nuclear Information System (INIS)

    Searle, A.G.

    1989-01-01

    The major components of genetic damage and associated human risks are discussed, together with the experimental evidence on induction rates of chromosome anomalies in mice, and monkeys male and female germ cells, using low and high LET low level irradiation. (UK)

  17. Low-level laser therapy and Calendula officinalis in repairing diabetic foot ulcers

    Directory of Open Access Journals (Sweden)

    Ana Flávia Machado de Carvalho

    Full Text Available Abstract OBJECTIVE To evaluate the effects of low-level laser therapy isolated and associated with Calendula officinalis oil in treating diabetic foot ulcers. METHOD An experimental, randomized, controlled, prospective, interventional clinical case study using a quantitative approach. The sample consisted of 32 diabetic patients of both genders. Participants were randomly divided into four groups. Doppler Ultrasound evaluation of the Ankle-Brachial Index, brief pain inventory and analog pain scale were performed at baseline and after 30 days. RESULTS Reduced pain was observed in the Low-level laser therapy and Low-level laser therapy associated with Essential Fatty Acids groups (p<0.01. Regarding the Ankle-Brachial Index and Doppler Ultrasound, all groups remained stable. By analyzing lesion area reduction, Low-level laser therapy associated with Essential fatty acids group showed a significance of p=0.0032, and the Low-level laser therapy group showed p=0.0428. CONCLUSION Low-level laser therapy, performed alone or associated with the Calendula officinalis oil was effective in relieving pain and accelerating the tissue repair process of diabetic foot.

  18. Low level laser therapy and hair regrowth: an evidence-based review.

    Science.gov (United States)

    Zarei, Mina; Wikramanayake, Tongyu C; Falto-Aizpurua, Leyre; Schachner, Lawrence A; Jimenez, Joaquin J

    2016-02-01

    Despite the current treatment options for different types of alopecia, there is a need for more effective management options. Recently, low-level laser therapy (LLLT) was evaluated for stimulating hair growth. Here, we reviewed the current evidence on the LLLT effects with an evidence-based approach, focusing more on randomized controlled studies by critically evaluating them. In order to investigate whether in individuals presenting with hair loss (male pattern hair loss (MPHL), female pattern hair loss (FPHL), alopecia areata (AA), and chemotherapy-induced alopecia (CIA)) LLLT is effective for hair regrowth, several databases including PubMed, Google Scholar, Medline, Embase, and Cochrane Database were searched using the following keywords: Alopecia, Hair loss, Hair growth, Low level laser therapy, Low level light therapy, Low energy laser irradiation, and Photobiomodulation. From the searches, 21 relevant studies were summarized in this review including 2 in vitro, 7 animal, and 12 clinical studies. Among clinical studies, only five were randomized controlled trials (RCTs), which evaluated LLLT effect on male and female pattern hair loss. The RCTs were critically appraised using the created checklist according to the Critical Appraisal for Therapy Articles Worksheet created by the Center of Evidence-Based Medicine, Oxford. The results demonstrated that all the performed RCTs have moderate to high quality of evidence. However, only one out of five studies performed intention-to-treat analysis, and only another study reported the method of randomization and subsequent concealment of allocation clearly; all other studies did not include this very important information in their reports. None of these studies reported the treatment effect of factors such as number needed to treat. Based on this review on all the available evidence about effect of LLLT in alopecia, we found that the FDA-cleared LLLT devices are both safe and effective in patients with MPHL and FPHL

  19. Low-level laser therapy improves visual acuity in adolescent and adult patients with amblyopia.

    Science.gov (United States)

    Ivandic, Boris T; Ivandic, Tomislav

    2012-03-01

    The purpose of this study was to examine the effects of low-level laser therapy (LLLT) on visual acuity in adolescent and adult patients with amblyopia. Currently, amblyopia can be treated successfully only in children. In this single-blinded, placebo-controlled study, 178 patients (mean age 46.8 years) with amblyopia caused by ametropia (110 eyes) or strabismus (121 eyes) were included. For LLLT, the area of the macula was irradiated through the conjunctiva from 1 cm distance for 30 sec with laser light (780 nm, 292 Hz, 1:1 duty cycle; average power 7.5 mW; spot area 3 mm(2)). The treatment was repeated on average 3.5 times, resulting in a mean total dose of 0.77 J/cm(2). No occlusion was applied, and no additional medication was administered. Best corrected distant visual acuity was determined using Snellen projection optotypes. In 12 patients (12 eyes), the multifocal visual evoked potential (M-VEP) was recorded. A control group of 20 patients (20 eyes) received mock treatment. Visual acuity improved in ∼90% of the eyes treated with LLLT (pamblyopia caused by ametropia and strabismus, respectively. The treatment effect was maintained for at least 6 months. The mean M-VEP amplitude increased by 1207 nV (pamblyopia caused by ametropia or strabismus.

  20. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    International Nuclear Information System (INIS)

    Canuto, K.S.; Guimaraes, O.R.; Geller, M.; Sergio, L.P.S.; Paoli, F.; Fonseca, A.S.

    2015-01-01

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. (author)

  1. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    Energy Technology Data Exchange (ETDEWEB)

    Canuto, K.S.; Guimaraes, O.R.; Geller, M. [Centro Universitario Serra dos Orgaos, Teresopolis, RJ (Brazil). Centro de Ciencias da Saude; Sergio, L.P.S. [Instituto de Biologia Roberto Alcantara Gomes, Rio de Janeiro, RJ (Brazil). Departamento de Biofisica e Biometria; Paoli, F. [Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, MG (Brazil). Departamento de Morfologia; Fonseca, A.S., E-mail: adnfonseca@ig.com.br [Universidade Federal do Estado do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Departamento de Ciencias Fisiologicas

    2015-10-15

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. (author)

  2. Alternatives to dose, quality factor and dose equivalent for low level irradiation

    International Nuclear Information System (INIS)

    Sondhaus, C.A.; Bond, V.P.; Feinendegen, L.E.

    1988-01-01

    Randomly occurring energy deposition events produced by low levels of ionizing radiation interacting with tissue deliver variable amounts of energy to the sensitive target volumes within a small fraction of the cell population. A model is described in which an experimentally derived function relating event size to cell response probability operates mathematically on the microdosimetric event size distribution characterizing a given irradiation and thus determines the total fractional number of responding cells; this fraction measures the effectiveness of the given radiation. Normalizing to equal numbers of events produced by different radiations and applying this cell response or hit size effectiveness function (HSEF) should define radiation quality, or relative effectiveness, on a more nearly absolute basis than do the absorbed dose and dose evaluation, which are confounded when applied to low level irradiations. Examples using both calculation and experimental data are presented. 15 refs., 18 figs

  3. Steroids block the anti-inflammatory effects of low level laser therapy

    Science.gov (United States)

    Lopes-Martins, Rodrigo Alvaro B.; Albertini, Regiane; Lopes-Martins, Patricia Sardinha L.; Iversen, Vegard V.; Bjordal, Jan M.

    2006-02-01

    Objective: Concomitant use of multiple therapies is common in musculoskeletal and airway disorders. Low level laser therapy (LLLT) is considered a promising therapy in arthritis, tendinopathies and rhinitis. We designed two animal studies to assess if the expected anti-inflammatory effect LLLT could be affected by resection of the adrenal gland or concomitant use of the cortisol antagonist mifepristone. Methods: Two studies were performed, with 40 male Wistar rats and with 40 Balb C male mice respectively.. In both studies, four groups received carrageenan and one control group received saline. At 1, 2, and 3 hours after injections, LLLT irradiation was performed with a dose of 7.5 J/cm2. In the rat study, two of the carrageenan groups had the adrenal gland dissected. In the mice study, two of the carrageenan-injected groups were in addition pre-treated with orally administered mifepristone. Results: In the rat paw study, LLLT reduced edema significantly compared to the carrageenan only group (1.5 vs 0.9 ml, peffect of LLLT could be totally blocked by adding the cortisol antagonist mifepristone ( pSteroid therapy should not be used concomitantly with LLLT, as the anti-inflammatory effect of LLLT is lost if cortisol receptors are downregulated.

  4. Low-Level Laser Therapy in the Treatment of Recurrent Aphthous Ulcers: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Fernando Alves Vale

    2015-01-01

    Full Text Available Recurrent aphthous ulcers (RAUs are the most common lesion found in the oral cavity. There is no definitive cure for RAUs and current treatments are aimed at minimizing symptoms. Since low-level laser therapy (LLLT modulates inflammatory responses, and promotes pain reduction and cellular biostimulation, LLLT can be suggested as an alternative treatment for RAUs. The literature concerning the potential of LLLT in the treatment of RAUs was evaluated. A systematic literature review identified 22 publications, of which only 2 studies were adopted. The eligibility criteria consisted of randomized controlled trials (RCTs. Both RCTs achieved significant results concerning LLLT and pain-level reductions and reduced healing times. Despite the variance in irradiation conditions applied in both studies, very similar wavelengths were adopted. There is accordingly strong evidence that wavelength plays an important role in RAU treatment. Taking into account the different parameters applied by selected RCTs, it is not possible to suggest that a specific protocol should be used. However, in light of the significant results found in both studies, LLLT can be suggested as an alternative for RAU treatment. Additional RCTs should be performed in order to reach a clinical protocol and better understand the application of LLLT in RAU treatment.

  5. Effects of low-level laser therapy on orthodontic tooth movement and root resorption after artificial socket preservation

    Directory of Open Access Journals (Sweden)

    Massoud Seifi

    2014-01-01

    Full Text Available Background: Low- level laser therapy has been used to stimulate the orthodontic tooth movements (OTM previously. Furthermore, in the orthodontic treatments accompanying tooth extractions, the adjacent teeth move towards the extraction sites and close the space in some cases. Then, the adjacent tooth movements must be prevented in the treatments requiring space. Laser stimulates and at some doses decelerates tooth movement; it also improves healing process and enhances osteogenesis. Hence, it can prevent movement by osteogenesis adjacent to the tooth. The present study investigated the effects of low-level laser therapy on the OTM and root resorption following artificial socket preservation. Materials and Methods: In this experimental animal trial, 16 male albino rabbits were selected with similar characteristics and randomly divided in two groups. Under general anesthesia, an artificial socket, 8 mm in height, was created in the mesial aspect of the first premolars of the rabbits and filled with demineralized freeze dried bone allograft (DFDBA. The first premolars were connected to the incisors using nickel titanium coil springs. In experimental group, gallium-aluminum-arsenide (GaAlAs laser was irritated mesial to first premolar where artificial socket was created continuously (808 nm. The cycle was 10 days irritation, 14 days rest, 10 days irritation, 14 days rest (Biostimulation mode. Control group was not laser irradiated. All animals were sacrificed after 48 days and the distance between the distal aspect of the first premolars, and the mesial surface of the second premolars was measured with leaf gauge. The specimens underwent histological assessments. Integrity of root and its resorption was observed under microscope calibration. The size of resorption lacunae was calculated in mm 2 . Normality of data was proved according to Kolmogorov-Smirnov analysis, and Student′s t-test was done. P value less than 0.05 was considered as significant

  6. The low level laser therapy in the management of neurological burning mouth syndrome. A pilot study

    Science.gov (United States)

    Romeo, Umberto; Del Vecchio, Alessandro; Capocci, Mauro; Maggiore, Claudia; Ripari, Maurizio

    2010-01-01

    Summary Background and objective. Burning Mouth Syndrome (BMS) is a common disease but still a diagnostic and therapeutic challenge for clinicians. Despite many studies its nature remains obscure and controversial; nowadays there is no consensus about definition, diagnosis and classification. BMS is characterized clinically by burning sensations in the tongue or other oral sites, often without clinical and laboratory findings. According to the etiology, BMS cases should be subdivided into three subtypes: BMS by local factors (lfBMS), BMS by systemic factors (sfBMS) and neurological BMS (nBMS), the most frequent, in which the symptom is caused by central or peripheral neurological malfunctions affecting in particular the taste pathway. To establish the type of BMS, both anamnesis and clinical examination, including laboratory tests, are necessary; nBMS cases will be recognized by exclusion of any other type. In case of lfBMS or sfBMS, the treatment of the main pathology will be resolutive; in nBMS cases many Authors proposed different pharmacological trials without satisfactory results and the current opinion is that a multidisciplinary approach is required to keep the condition under control. This pilot study aimed to investigate whether the biostimulative effect of Low Level Laser Therapy (LLLT) could enhance the symptoms of nBMS cases, improving patients’ quality of life. Study design/materials and methods. Among 160 patients affected by oral burning sensation attending to the Oral Pathology Complex Operative Unit of the Department of Stomatological Sciences of Sapienza University of Rome, 77 resulted affected by nBMS. Twenty-five of these patients, 16 females and 9 males, were randomly selected for low level laser applications. All the patients were irradiated with a double diode laser (Lumix 2 Prodent, Italy) emitting contemporarily at 650 nm and 910 nm, with a fluence of 0.53 J/cm2 for 15 minutes twice a week for 4 weeks. The areas of irradiation were the

  7. Effects of a low level laser on periodontal tissue in hypofunctional teeth.

    Directory of Open Access Journals (Sweden)

    Hidetaka Hayashi

    Full Text Available Malocclusions, such as an open bite and high canines, are often encountered in orthodontic practice. Teeth without occlusal stimuli are known as hypofunctional teeth, and numerous atrophic changes have been reported in the periodontal tissue, including reductions in blood vessels in the periodontal ligament (PDL, heavy root resorption, and reduced bone mineral density (BMD in the alveolar bone. Low Level Laser (LLL has been shown to have a positive effect on bone formation and the vasculature. Although the recovery of hypofunctional teeth remains unclear, LLL is expected to have a positive influence on periodontal tissue in occlusal hypofunction. The aim of the present study was to elucidate the relationship between LLL and periodontal tissue in occlusal hypofunction. Twenty-four male rats aged 5 weeks were randomly divided into control and hypofunctional groups. An anterior metal cap and bite plate were attached to the maxillary and mandibular incisors in the hypofunctional group to simulate occlusal hypofunction in the molars. LLL irradiation was applied to the maxillary first molar through the gingival sulcus in half of the rats. Rats were divided into four groups; control, control+LLL, hypofunctional, and hypofunctional+LLL. Exposure to LLL irradiation was performed for 3 minutes every other day for 2 weeks. Animals were examined by Micro-CT at 5 and 7 weeks and were subsequently sacrificed. Heads were resected and examined histologically and immunohistologically. The hypofunctional group had obvious stricture of the PDL. However, no significant differences were observed in the PDL and alveolar bone between the hypofunctional+LLL and the control groups. In addition, the expression of basic fibroblast growth factor (bFGF and vascular endothelial growth factor (VEGF-positive cells were higher in the hypofunctional + LLL group than in the hypofunctional group. These results indicated that LLL enhanced the production of bFGF and VEGF in the

  8. Evaluation of low-level laser therapy in the treatment of masticatory muscles spasticity in children with cerebral palsy

    Science.gov (United States)

    Santos, Maria Teresa Botti Rodrigues; Diniz, Michele Baffi; Gouw-Soares, Sheila Cynthia; Lopes-Martins, Rodrigo Alvaro Brandão; Frigo, Lucio; Baeder, Fernando Martins

    2016-02-01

    Spasticity is a motor disorder frequently present in individuals with cerebral palsy (CP). This study aimed to evaluate the effect of low-level laser therapy (LLLT) on the spasticity of the masseter and anterior temporal muscle fibers in children with CP over three weeks of intermittent laser exposures. The bite force (BF) of the masticatory muscles and the amplitude of mouth opening were evaluated before and after laser irradiation in 30 children with CP. Both sides of the masseter and temporalis muscles were irradiated with low-intensity diode laser pulses of 808-nm wavelength six times over three consecutive weeks. During the subsequent three weeks of postlaser exposures, although no laser treatment was applied, the evaluation parameters were measured and recorded. A significant improvement in the amplitude of mouth opening and a decrease in the BF were observed in the weeks following LLLT (Peffective short-term therapeutic tool. This method increased the amplitude of mouth opening and decreased the muscle tonus of children with spastic CP over a time course of three weeks of intermittent laser applications.

  9. Low-level laser therapy improves vision in a patient with retinitis pigmentosa.

    Science.gov (United States)

    Ivandic, Boris T; Ivandic, Tomislav

    2014-03-01

    This case report describes the effects of low-level laser therapy (LLLT) in a single patient with retinitis pigmentosa (RP). RP is a heritable disorder of the retina, which eventually leads to blindness. No therapy is currently available. LLLT was applied using a continuous wave laser diode (780 nm, 10 mW average output at 292 Hz, 50% pulse modulation). The complete retina of eyes was irradiated through the conjunctiva for 40 sec (0.4 J, 0.333 W/cm2) two times per week for 2 weeks (1.6 J). A 55-year-old male patient with advanced RP was treated and followed for 7 years. The patient had complained of nyctalopia and decreasing vision. At first presentation, best visual acuity was 20/50 in each eye. Visual fields were reduced to a central residual of 5 degrees. Tritan-dyschromatopsy was found. Retinal potential was absent in electroretinography. Biomicroscopy showed optic nerve atrophy, and narrow retinal vessels with a typical pattern of retinal pigmentation. After four initial treatments of LLLT, visual acuity increased to 20/20 in each eye. Visual fields normalized except for a mid-peripheral absolute concentric scotoma. Five years after discontinuation of LLLT, a relapse was observed. LLLT was repeated (another four treatments) and restored the initial success. During the next 2 years, 17 additional treatments were performed on an "as needed" basis, to maintain the result. LLLT was shown to improve and maintain vision in a patient with RP, and may thereby have contributed to slowing down blindness.

  10. Photobiomodulation of surgical wound dehiscence in a diabetic individual by low-level laser therapy following median sternotomy

    Directory of Open Access Journals (Sweden)

    Snehil Dixit

    2013-01-01

    Full Text Available In this single case study, we attempt to outline the possible effect of low-level laser therapy (LLLT on delayed wound healing and pain in chronic dehiscent sternotomy of a diabetic individual. The methods that were employed to evaluate changes pre and post irradiation were wound photography, wound area measurement, pressure ulcer scale of healing (PUSH, and visual analogue scale (VAS for pain. After irradiation, proliferation of healthy granulation tissue was observed with decrease in scores of PUSH for sternal dehiscence and VAS for bilateral shoulders and sternal dehiscence. We found that LLLT irradiation could be a novel method of treatment for chronic sternal dehiscence following coronary artery bypass grafting, as it augments wound healing with an early closure of the wound deficit. Hence, this might be translated into an early functional rehabilitation and decreased pain perception of an individual following surgical complication.

  11. Low-level lasers affect Escherichia coli cultures in hyperosmotic stress

    Science.gov (United States)

    Pinheiro, C. C.; Barboza, L. L.; Paoli, F.; Fonseca, A. S.

    2015-08-01

    Physical characteristics and practical properties have made lasers of interest for biomedical applications. Effects of low-level lasers on biological tissues could occur or be measurable depending on cell type, presence of a pathologic process or whether the cells are in an adverse environment. The objective of this work was to evaluate the survival, morphology and filamentation of E. coli cells proficient and deficient in the repair of oxidative DNA lesions exposed low-level red and infrared lasers submitted to hyperosmotic stress. Wild type and endonuclease VIII deficient E. coli cells in exponential and stationary growth phase were exposed to red and infrared lasers and submitted to hyperosmotic stress. Cell viability, filamentation phenotype and cell morphology were evaluated. Cell viability was not significantly altered but previous laser exposure induced filamentation and an altered area of stressed cells depending on physiologic condition and presence of the DNA repair. Results suggest that previous exposure to low-level red and infrared lasers could not affect viability but induced morphologic changes in cells submitted to hyperosmotic stress depending on physiologic conditions and repair of oxidative DNA lesions.

  12. Novel Approach to Treating Androgenetic Alopecia in Females With Photobiomodulation (Low-Level Laser Therapy).

    Science.gov (United States)

    Friedman, Shelly; Schnoor, Patricia

    2017-06-01

    Photobiomodulation, also referred to as low-level laser therapy (LLLT), has been studied and used for (among other diseases) the promotion of hair regrowth. A clinical study was developed to define the physiologic effects that occur when the human hair follicle and surrounding tissue structures are exposed to laser light using a novel device that is fitted with an array of laser diode sources operating at 650 nm and placed inside a sports cap to promote discretion while in use. The study demonstrates that low-level laser treatment of the scalp every other day for 17 weeks using the HANDI-DOME LASER device is a safe and effective treatment for androgenetic alopecia in healthy females between the ages of 18 to 60 with Fitzpatrick skin Types I to IV and Ludwig-Savin Baldness Scale I-2 to II-2 baldness patterns. Subjects receiving LLLT at 650 nm achieved a 51% increase in hair counts as compared with sham-treated control patients in this multicenter randomized controlled trial. These results suggest that the emerging technology of low-level laser therapy may play a potentially significant role in health care providers' armamentarium for the disease androgenic alopecia.

  13. Effect of low level prenatal X-irradiation on postnatal growth in the Wistar rat

    International Nuclear Information System (INIS)

    Jensh, R.P.; Brent, R.L.

    1988-01-01

    Forty-five pregnant Wistar strain rats were exposed to 0.0, 0.4, 0.6, or 0.8 Gy X-radiation on the 9th or 17th day of gestation to determined if prenatal X-irradiation would result in alterations in postnatal growth or growth rate. The mothers delivered their offspring, and the litters were reduced to a maximum of eight per litter on the second postnatal day. The 336 offspring were weighed weekly from day 3 until day 86, at which time they were killed, an autopsy was performed, and selected organs were removed and weighed. Postnatal growth rates did not differ significantly in irradiated offspring compared to sham irradiated animals. Irradiation on the 9th day, at any of the 3 dosage levels, did not result in significant differences in weekly weight. Weekly weight remained significantly lower due to irradiation on the 17th day of gestation. The gonadal weight ratio was significantly reduced in males irradiated on the 9th day. There were not other statistically significant changes in organ weight or organ/body weight ratios due to these levels of prenatal X-irradiation on the 9th or 17th day of pregnancy. These results indicate that low level prenatal X-irradiation, on the 17th day of rat gestation, causes prenatal growth retardation, evident at birth, which is not recuperable postnatally. Exposure to x-radiation at this time, however, does not affect the rate at which offspring grow during postnatal life. Offspring are smaller because they never fully recover from the original radiation-induced prenatal growth retardation

  14. Assessment of the effectiveness of low level laser in the treatment of alveolar osteitis

    Directory of Open Access Journals (Sweden)

    Jovanović Goran

    2011-01-01

    Full Text Available Background/Aim. Alveolar osteitis (AO is the extraction wound healing disorder with a presence of severe pain. Low level laser therapy stimulates cell metabolism and microcirculation, have has pronounced analgesic, antiedematous and anti-inflammatory effect and speeds up wound healing process. The aim of this study was to present results of clinical research that examined the effectiveness of low level laser in pain relief and healing of extraction wounds with alveolar osteitis in the lower jaw which was formed on the second day after tooth extraction. Methods. The study was conducted on 60 subjects divided into the study and the control group. In both groups extraction wounds were processed in similar way, except that in the study group was applied daily treatment of low level laser with a total of eight sessions of radiation, while in the control group extraction wounds were dressed with zinc oxide eugenol paste, which was changed every 48 hours up to the pain cessation. Measurement of pain intensity was done with a visual analogue scale (VAS 10 min prior to processing of extraction wounds and daily for the next eight days. Assessment of the effectiveness of low level laser on healing of extraction wounds was performed on the day eight of the treatment. Results. On the day five after beginning of the treatment of extraction wounds with alveolar osteitis in the patients of the study group a lower average value of pain as compared to the control group was registered. This difference was increased within the following days. Extraction wounds healing in the study group was more successful and faster than in the control group. Conclusion. This study suggested that the reduction of pain was more pronounced in the patients with alveolar osteitis whose extraction wounds were subjected to low level laser radiation in comparison to those in which extraction wounds were treated with zinc oxide eugenol paste.

  15. Measurements of low-level prepulse on Nike KrF laser

    International Nuclear Information System (INIS)

    Karasik, Max; Mostovych, A.N.; Lehmberg, R.H.; Chan, Y.; Weaver, J.L.; Obenschain, S.P.

    2005-01-01

    The krypton fluoride (KrF) laser is a leading candidate driver for inertial fusion energy. Some of the current fusion target designs call for targets with thin metallic coatings. These targets could be particularly susceptible to preheat by a low-level laser prepulse. Knowledge of the prepulse can be important in understanding and modeling the behavior of such targets. This paper presents measurements of low-level prepulse on target with the Nike KrF laser. Sources of prepulse are discussed and measurements are performed under several specific laser conditions in order to evaluate the relative contribution of these sources to the overall prepulse. Prepulse is found to be ∼2x10 -7 from peak intensity for approximately 120 ns prior to the main laser pulse. Prepulse energy density on target is ∼2 J/cm 2 . The first laser amplifier in the time- and angle-multiplexed section of the laser is found to be the dominant source of prepulse

  16. Low-level laser therapy and Calendula officinalis in repairing diabetic foot ulcers.

    Science.gov (United States)

    Carvalho, Ana Flávia Machado de; Feitosa, Maura Cristina Porto; Coelho, Nayana Pinheiro Machado de Freitas; Rebêlo, Veruska Cronemberger Nogueira; Castro, Juçara Gonçalves de; Sousa, Patrícia Regina Gomes de; Feitosa, Valrian Campos; Arisawa, Emilia Angela Lo Schiavo

    2016-01-01

    To evaluate the effects of low-level laser therapy isolated and associated with Calendula officinalis oil in treating diabetic foot ulcers. An experimental, randomized, controlled, prospective, interventional clinical case study using a quantitative approach. The sample consisted of 32 diabetic patients of both genders. Participants were randomly divided into four groups. Doppler Ultrasound evaluation of the Ankle-Brachial Index, brief pain inventory and analog pain scale were performed at baseline and after 30 days. Reduced pain was observed in the Low-level laser therapy and Low-level laser therapy associated with Essential Fatty Acids groups (pgrupos. Ultrassom Doppler, avaliação do Índice Tornozelo-Braquial, Inventário breve de dor e escala de dor analógica foram realizados no início e após 30 dias. Houve redução da dor nos grupos Terapia a Laser de Baixa Intensidade e Terapia a Laser de Baixa intensidade associada aos Ácidos Graxos Essenciais, com pgrupos mantiveram-se estáveis. Na análise da redução de área da lesão, o grupo Terapia a Laser de Baixa Intensidade associada aos Ácidos Graxos Essenciais apresentou uma significância p=0,0032, e o grupo Terapia a Laser de Baixa Intensidade, p=0,0428. A Terapia a Laser de Baixa Intensidade, realizada tanto isoladamente quanto associada ao óleo de Calendula officinalis, foi eficaz no alívio da dor e na aceleração do processo de reparo tecidual de pé diabético.

  17. Efficacy of low-level laser therapy on orofacial pain: A literature review

    Directory of Open Access Journals (Sweden)

    Haleh Zokaee

    2018-01-01

    Full Text Available Low-level laser therapy (LLLT is a therapeutic approach to treat orofacial pain using a 600–1000 nm laser with a <500 mW power. The efficacy of LLLT is due to the chemical reactions causing an anti-inflammatory and analgesic effect on the affected regions. The aim of this study is to review the effects of low-level laser application on orofacial pain in the English articles released since 2017. Our search keywords were 'low-level laser therapy, temporomandibular disease (TMD, mucositis and orofacial pain'. The most relevant papers were clinical trial, review and meta-analysis articles. 26 out of 243 searched articles were selected from PubMed, Google Scholar and Science Direct and reviewed. Most of the studies reported the positive role of LLLT on orofacial pain relief regardless of their variable procedures; however, the exact mechanism of action still remains unclear. Some studies indicated that LLLT has significantly reduced pain, reduceamount of clicking and both masseter and temporal muscles activityin TMD. As an overall result, it is concluded that LLLT can be served as a therapeutic method for myofascial pain, mucositis and temporomandibular joint disorders and this is due to its analgesic features.

  18. Effect of preoperative ibuprofen in controlling postendodontic pain with and without low-level laser therapy in single visit endodontics: A randomized clinical study

    Directory of Open Access Journals (Sweden)

    Shahnaz Nabi

    2018-01-01

    Full Text Available Aim: The aim of this study is to evaluate the effect of low-level laser irradiation and ibuprofen in reducing the onset and severity of postoperative pain following single visit endodontics. Materials and Methods: One hundred and twenty patients were recruited for this study. Group A (n = 30 patients were administered 400 mg of ibuprofen orally 1 h before the institution of an endodontic procedure. Group B (n = 30 patients were given irradiation of a low-level laser at 50 Hz for 3 min after the standard endodontic procedure at the periapical region on both buccal and lingual aspect. Group C (n = 30 patients were given preoperative ibuprofen followed with a low-level laser at 50 Hz for 3 min after endodontic treatment. Group D (n = 30 patients were administered no preoperative ibuprofen nor low-level laser irradiation after the endodontic procedure. The patient immediately recorded his/her pain perception on the Heft Parker pain survey after completion of the appointment and at 4, 8, 12, 24, and 48 h postoperatively. Inter group analysis was carried out using the analysis of variances with “least significant difference” post hoc test. For intra group analysis, Student's t-test was used. Chi-square test was applied for nonparametric data. Results: Pain was significantly reduced in all the treatment groups postoperatively. Ibuprofen showed significant pain reduction at 4 h and 8 h period. The combination of low-level laser and ibuprofen showed the best results in terms of postoperative pain reduction. Conclusion: This study proved that low-level laser therapy can be an effective alternative for conventional use of nonsteroidal anti-inflammatory drugs in controlling postendodontic pain thereby eliminating the adverse effects of such drugs on the patients.

  19. Treatment of burning mouth syndrome with a low-level energy diode laser.

    Science.gov (United States)

    Yang, Hui-Wen; Huang, Yu-Feng

    2011-02-01

    To test the therapeutic efficacy of low-level energy diode laser on burning mouth syndrome. Burning mouth syndrome is characterized by burning and painful sensations in the mouth, especially the tongue, in the absence of significant mucosal abnormalities. Although burning mouth syndrome is relatively common, little is known regarding its etiology and pathophysiology. As a result, no treatment is effective in all patients. Low-level energy diode laser therapy has been used in a variety of chronic and acute pain conditions, including neck, back and myofascial pain, degenerative osteoarthritis, and headache. A total of 17 patients who had been diagnosed with burning mouth syndrome were treated with an 800-nm wavelength diode laser. A straight handpiece was used with an end of 1-cm diameter with the fiber end standing 4 cm away from the end of handpiece. When the laser was applied, the handpiece directly contacted or was immediately above the symptomatic lingual surface. The output used was 3 W, 50 msec intermittent pulsing, and a frequency of 10 Hz, which was equivalent to an average power of 1.5 W/cm(2) (3 W × 0.05 msec × 10 Hz = 1.5 W/cm(2)). Depending on the involved area, laser was applied to a 1-cm(2) area for 70 sec until all involved area was covered. Overall pain and discomfort were analyzed with a 10-cm visual analogue scale. All patients received diode laser therapy between one and seven times. The average pain score before the treatment was 6.7 (ranging from 2.9 to 9.8). The results showed an average reduction in pain of 47.6% (ranging from 9.3% to 91.8%). The burning sensation remained unchanged for up to 12 months. Low-level energy diode laser may be an effective treatment for burning mouth syndrome.

  20. Acute effects of low-level laser therapy (660 nm) on oxidative stress levels in diabetic rats with skin wounds.

    Science.gov (United States)

    Denadai, Amanda Silveira; Aydos, Ricardo Dutra; Silva, Iandara Schettert; Olmedo, Larissa; de Senna Cardoso, Bruno Mendonça; da Silva, Baldomero Antonio Kato; de Carvalho, Paulo de Tarso Camillo

    2017-09-01

    Laser therapy influences oxidative stress parameters such as the activity of antioxidant enzymes and the production of reactive oxygen species. To analyze the effects of low-level laser therapy on oxidative stress in diabetics rats with skin wounds. Thirty-six animals were divided into 4 groups: NDNI: non-diabetic rats with cutaneous wounds that not received laser therapy; NDI: non-diabetic rats with cutaneous wounds that received laser therapy; DNI: diabetic rats with skin wounds who did not undergo laser therapy; DI: rats with diabetes insipidus and cutaneous wounds and received laser therapy. The animals were treated with LLLT (660 nm, 100 mW, 6 J/cm, spot size 0.028 cm). On the day of killing the animals, tissue-wrapped cutaneous wounds were collected and immediately frozen, centrifuged, and stored to analyze malondialdehyde (MDA) levels. Significant difference was observed within the groups of MDA levels (ANOVA, p = 0.0001). Tukey's post-hoc test showed significantly lower values of MDA in irradiated tissues, both in diabetic and non-diabetic rats. ANOVA of the diabetic group revealed a significant difference (p < 0.01) when all groups, except NDI and DI, were compared. LLLT was effective in decreasing MDA levels in acute surgical wounds in diabetic rats.

  1. Chiropractic management of Bell palsy with low level laser and manipulation: a case report.

    Science.gov (United States)

    Rubis, Lisa M

    2013-12-01

    The purpose of this case report is to describe chiropractic management including the use of cold laser and chiropractic manipulation in the treatment of a patient with Bell palsy. A 40-year-old male patient had a 10-day history of facial paralysis on his left side, including the inability to close his left eye, which also had tearing and a burning sensation. The patient had trouble lifting his left lip and complained of drooling while brushing his teeth. There was no previous history of similar symptoms or a recent infection. Prior treatment had included oral steroids. The patient was treated with low-level laser therapy and chiropractic manipulation 2 times in 4 days. The laser was applied along the course of the facial nerve for 30 seconds at each point and for 1 minute at the stylomastoid foramen. The laser used was a GaAs class 4 laser with a wavelength of 910 nm. The patient perceived a 70% to 80% improvement of facial movement after the first treatment. After the second treatment, the patient reported full control of his facial movements. A patient with acute facial paralysis appeared to have complete resolution of his symptoms following the application of low-level laser therapy and chiropractic manipulation.

  2. Effect of low-level laser treatment on cochlea hair-cell recovery after ototoxic hearing loss

    Science.gov (United States)

    Rhee, Chung-Ku; He, Peijie; Jung, Jae Yun; Ahn, Jin-Chul; Chung, Phil-Sang; Lee, Min Young; Suh, Myung-Whan

    2013-12-01

    The primary cause of hearing loss includes damage to cochlear hair cells. Low-level laser therapy (LLLT) has become a popular treatment for damaged nervous systems. Based on the idea that cochlea hair cells and neural cells are from same developmental origin, the effect of LLLT on hearing loss in animal models is evaluated. Hearing loss animal models were established, and the animals were irradiated by 830-nm diode laser once a day for 10 days. Power density of the laser treatment was 900 mW/cm2, and the fluence was 162 to 194 J. The tympanic membrane was evaluated after LLLT. Thresholds of auditory brainstem responses were evaluated before treatment, after gentamicin, and after 10 days of LLLT. Quantitative scanning electron microscopic (SEM) observations were done by counting remaining hair cells. Tympanic membranes were intact at the end of the experiment. No adverse tissue reaction was found. On SEM images, LLLT significantly increased the number of hair cells in middle and basal turns. Hearing was significantly improved by laser irradiation. After LLLT treatment, both the hearing threshold and hair-cell count significantly improved.

  3. Effects of low-level laser therapy on orthodontic tooth movement and root resorption after artificial socket preservation.

    Science.gov (United States)

    Seifi, Massoud; Atri, Faezeh; Yazdani, Mohammad Masoud

    2014-01-01

    Low- level laser therapy has been used to stimulate the orthodontic tooth movements (OTM) previously. Furthermore, in the orthodontic treatments accompanying tooth extractions, the adjacent teeth move towards the extraction sites and close the space in some cases. Then, the adjacent tooth movements must be prevented in the treatments requiring space. Laser stimulates and at some doses decelerates tooth movement; it also improves healing process and enhances osteogenesis. Hence, it can prevent movement by osteogenesis adjacent to the tooth. The present study investigated the effects of low-level laser therapy on the OTM and root resorption following artificial socket preservation. In this experimental animal trial, 16 male albino rabbits were selected with similar characteristics and randomly divided in two groups. Under general anesthesia, an artificial socket, 8 mm in height, was created in the mesial aspect of the first premolars of the rabbits and filled with demineralized freeze dried bone allograft (DFDBA). The first premolars were connected to the incisors using nickel titanium coil springs. In experimental group, gallium-aluminum-arsenide (GaAlAs) laser was irritated mesial to first premolar where artificial socket was created continuously (808 nm). The cycle was 10 days irritation, 14 days rest, 10 days irritation, 14 days rest (Biostimulation mode). Control group was not laser irradiated. All animals were sacrificed after 48 days and the distance between the distal aspect of the first premolars, and the mesial surface of the second premolars was measured with leaf gauge. The specimens underwent histological assessments. Integrity of root and its resorption was observed under microscope calibration. The size of resorption lacunae was calculated in mm(2). Normality of data was proved according to Kolmogorov-Smirnov analysis, and Student's t-test was done. P value less than 0.05 was considered as significant. The mean OTM were 5.68 ± 1.21 mm in the control

  4. An in vitro study of the effects of low-level laser radiation on human blood

    Science.gov (United States)

    Siposan, Dan G.; Lukacs, Adalbert

    2003-12-01

    In the last time the study of the effects of LLLR on the blood is considered to be a subject of great importance in elucidating the mechanisms of action between LLLR and biologic tissues. Different methods of therapy by blood irradiation have been developed and used in clinical purposes with benefic effects. This study investigates some in vitro effects of LLLR on some selected rheologic indices of human blood. After establishing whether or not damaging effects could appear due to laser irradiation of the blood, we tried to find a new method for rejuvenating the blood preserved in MacoPharma-type bags. Blood samples were obtained from adult regular donors (volunteers). HeNe laser and laser diodes were used as radiation source, in a wide range of wavelengths, power densities, doses and other parameters of irradiation protocol. In the first series of experiments we established that LLLR does not alter the fresh blood from healthy donors, for doses between 0 and 10 J/cm3 and power densities between 30 and 180 mW/cm3. In the second series of experiments we established that LLLR does have, in some specific conditions, a revitalizing effect on the erythrocytes in preserved blood. We concluded that laser irradiation of the preserved blood, following a selected protocol of irradiation, could be used as a new method to improve the performances of preservation: prolonging the period of storage and blood rejuvenation before transfusion.

  5. Paramecium tetraurelia growth stimulation under low-level chronic irradiation: investigations on a possible mechanism

    International Nuclear Information System (INIS)

    Croute, F.; Soleilhavoup, J.P.; Vidal, S.; Dupouy, D.; Planel, H.

    1982-01-01

    Experiments were carried out to demonstrate the effects of low-level chronic irradiation on Paramecium tetraurelia proliferation. Biological effects were strongly dependent on the bacterial density of culture medium and more exactly on the catalase content of the medium. Significant growth stimulation was found under 60 Co chronic irradiation at a dose rate of 2 rad/year when paramecia were grown in a medium containing a high bacterial concentration (2.5 x 10 2 cells/m) or supplemented with catalase (300 U/ml). In a medium with a low bacterial density (1 x 10 6 cell/ml) or supplemented with a catalase activity inhibitor, growth simulation was preceded by a transitory inhibiting effect which could be correlated with extracellularly radioproduced H 2 O 2 . H 2 O 2 addition appeared to be able to simulate the biological effects of chronic irradiation. A possible mechanism is discussed.We proposed that the stimulating effects were the result of intracellular enzymatic scavenging of radioproduced H 2 O 2

  6. Evaluation Of Low Level Laser Therapy On Body Constitution And Leptin Hormone By Radioimmunoassay

    International Nuclear Information System (INIS)

    Ali, S.S.Y.

    2012-01-01

    Asymmetric fat distribution with excessive fat accumulation in particular areas often affects a person's self-image, self esteem, and overall quality of life. Purpose of the study: to investigate the efficacy of the low level laser therapy (LLLT) on body constitution and leptin hormone by radioimmunoassay. Methods: Twenty women were included in this study. Their ages ranged from 30- 40 years. They were divided into two groups of equal number. Procedures: -Group A (Overweight group): included 10 women with BMI ≥ 25- 29.9-Group B (Obese group): included 10 women with BMI ≥ 30.both groups received LLLT, for 30 minutes, 2 times per week for 8 weeks as a total period of treatment. BMI, WC, HC, WHR, serum Leptin, cholesterol and triglyceride level were measured before and after finishing the study. Results: There was significant improvement in anthropometric measurements( on both abdomen and thigh fats) of both groups treated with low level laser therapy, decrease in serum leptin level in over weight group and increase in triglyceride serum level in both groups within normal level Conclusion: low level laser therapy is effective as a noninvasive and safe method of body contouring .

  7. Efficacy of Low Level Laser Therapy After Hand Flexor Tendon Repair

    Science.gov (United States)

    Ayad, K. E.; El Gohary, H. M.; Abd Elrahman, M.; Abd El Mejeed, S. F.; Bekheet, A. B.

    2009-09-01

    Flexor tendon injury is a common problem requiring suturing repair followed by early postoperative mobilization. Muscle atrophy, joint stiffness, osteoarthritis, infection, skin necrosis, ulceration of joint cartilage and tendocutaneous adhesion are familiar complications produced by prolonged immobilization of surgically repaired tendon ruptures. The purpose of this study was to clarify the importance of low level laser therapy after hand flexor tendon repair in zone II. Thirty patients aging between 20 and 40 years were divided into two groups. Patients in group A (n = 15) received a conventional therapeutic exercise program while patients in group B (n = 15) received low level laser therapy combined with the same therapeutic exercise program. The results showed a statistically significant increase in total active motion of the proximal and distal interphalangeal joints as well as maximum hand grip strength at three weeks and three months postoperative, but improvement was more significant in group B. It was concluded that the combination of low level laser therapy and early therapeutic exercises was more effective than therapeutic exercises alone in improving total active motion of proximal and distal interphalangeal joints and hand grip strength after hand flexor tendon repair.

  8. Effect of Low-Level Laser Stimulation on EEG Power in Normal Subjects with Closed Eyes

    Directory of Open Access Journals (Sweden)

    Jih-Huah Wu

    2013-01-01

    Full Text Available In a previous study, we found that the low-level laser (LLL stimulation at the palm with a frequency of 10 Hz was able to induce significant brain activation in normal subjects with opened eyes. However, the electroencephalography (EEG changes to LLL stimulation in subjects with closed eyes have not been studied. In the present study, the laser array stimulator was applied to deliver insensible laser stimulations to the palm of the tested subjects with closed eyes (the laser group. The EEG activities before, during, and after the laser stimulation were collected. The EEG amplitude powers of each EEG frequency band at 19 locations were calculated. These power data were then analyzed by SPSS software using repeated-measure ANOVAs and appropriate posthoc tests. We found a pronounced decrease in the EEG power in alpha-bandwidth during laser simulation and then less decrease in the EEG power in delta-bandwidth in normal subjects with laser stimulation. The EEG power in beta-bandwidth in the right occipital area also decreased significantly in the laser group. We suggest that LLL stimulation might be conducive to falling into sleep in patients with sleep problems.

  9. Biostimulatory effects of low-level laser therapy on epithelial cells and gingival fibroblasts treated with zoledronic acid

    Science.gov (United States)

    Basso, F. G.; Pansani, T. N.; Turrioni, A. P. S.; Kurachi, C.; Bagnato, V. S.; Hebling, J.; de Souza Costa, C. A.

    2013-05-01

    Low-level laser therapy (LLLT) has been considered as an adjuvant treatment for bisphosphonate-related osteonecrosis, presenting positive clinical outcomes. However, there are no data regarding the effect of LLLT on oral tissue cells exposed to bisphosphonates. This study aimed to evaluate the effects of LLLT on epithelial cells and gingival fibroblasts exposed to a nitrogen-containing bisphosphonate—zoledronic acid (ZA). Cells were seeded in wells of 24-well plates, incubated for 48 h and then exposed to ZA at 5 μM for an additional 48 h. LLLT was performed with a diode laser prototype—LaserTABLE (InGaAsP—780 nm ± 3 nm, 25 mW), at selected energy doses of 0.5, 1.5, 3, 5, and 7 J cm-2 in three irradiation sessions, every 24 h. Cell metabolism, total protein production, gene expression of vascular endothelial growth factor (VEGF) and collagen type I (Col-I), and cell morphology were evaluated 24 h after the last irradiation. Data were statistically analyzed by Kruskal-Wallis and Mann-Whitney tests at 5% significance. Selected LLLT parameters increased the functions of epithelial cells and gingival fibroblasts treated with ZA. Gene expression of VEGF and Col-I was also increased. Specific parameters of LLLT biostimulated fibroblasts and epithelial cells treated with ZA. Analysis of these in vitro data may explain the positive in vivo effects of LLLT applied to osteonecrosis lesions.

  10. Biostimulatory effects of low-level laser therapy on epithelial cells and gingival fibroblasts treated with zoledronic acid

    International Nuclear Information System (INIS)

    Basso, F G; Pansani, T N; Turrioni, A P S; Hebling, J; De Souza Costa, C A; Kurachi, C; Bagnato, V S

    2013-01-01

    Low-level laser therapy (LLLT) has been considered as an adjuvant treatment for bisphosphonate-related osteonecrosis, presenting positive clinical outcomes. However, there are no data regarding the effect of LLLT on oral tissue cells exposed to bisphosphonates. This study aimed to evaluate the effects of LLLT on epithelial cells and gingival fibroblasts exposed to a nitrogen-containing bisphosphonate—zoledronic acid (ZA). Cells were seeded in wells of 24-well plates, incubated for 48 h and then exposed to ZA at 5 μM for an additional 48 h. LLLT was performed with a diode laser prototype—LaserTABLE (InGaAsP—780 nm ± 3 nm, 25 mW), at selected energy doses of 0.5, 1.5, 3, 5, and 7 J cm −2 in three irradiation sessions, every 24 h. Cell metabolism, total protein production, gene expression of vascular endothelial growth factor (VEGF) and collagen type I (Col-I), and cell morphology were evaluated 24 h after the last irradiation. Data were statistically analyzed by Kruskal–Wallis and Mann–Whitney tests at 5% significance. Selected LLLT parameters increased the functions of epithelial cells and gingival fibroblasts treated with ZA. Gene expression of VEGF and Col-I was also increased. Specific parameters of LLLT biostimulated fibroblasts and epithelial cells treated with ZA. Analysis of these in vitro data may explain the positive in vivo effects of LLLT applied to osteonecrosis lesions. (paper)

  11. Systematic review of low-level laser therapy for adult androgenic alopecia.

    Science.gov (United States)

    Delaney, Sean W; Zhang, Paul

    2017-12-29

    Alopecia is a common disorder affecting over half of the world's population. Within this condition, androgenic alopecia (AA) is the most common type, affecting 50% of males over 40 and 75% of females over 65. Anecdotal paradoxical hypertrichosis noted during laser epilation has generated interest in the possibility of using laser to stimulate hair growth. In this study, we aimed to critically appraise the application of low-level laser therapy for the treatment of AA in adults. A systematic review was performed on studies identified on Medline, EMBASE, Cochrane database, and clinicaltrials.org. Double-blinded randomized controlled trials were selected and analyzed quantitatively (meta-analysis) and qualitatively (quality of evidence, risk of bias). Low-level laser therapy appears to be a promising noninvasive treatment for AA in adults that is safe for self-administration in the home setting. Although shown to effectively stimulate hair growth when compared to sham devices, these results must be interpreted with caution. Further studies with larger samples, longer follow-up, and independent funding sources are necessary to determine the clinical effectiveness of this novel therapy.

  12. Role Of SYNBIOTICS And Low Level GAMMA Irradiation Treatments In Improving Performance Of Japanese Quails

    International Nuclear Information System (INIS)

    ABU-TALEB, A.M.

    2009-01-01

    A total number of 800 Japanese quail eggs were obtained from a parent flock maintained the poultry research unit of the Biological Application Department, Nuclear Research Centre at Inshas, Egypt, and used in the present study. Before incubating the eggs, they were divided into two equal groups of 400 eggs each; the 1 st group was exposed to a low level of gamma irradiation at 50 rad before sitting while the 2 nd group did not exposed to gamma irradiation. After hatching of the two groups, fertility, hatchability, embryonic mortality and hatching weight were determined. Hatched quail chicks from each group (1 and 2) were divided into four identical subgroups and all fed the basal diet but with a different supplement. The diet of the 1 st subgroup was supplemented with 2.5% Lactobacilli, the 2 nd with 1.5% lactose, the 3 rd with 2.5% Lactobacilli plus 1.5% lactose, while the 4 th subgroup was fed the basal diet only and served as control. The results showed decreased embryonic mortality and increased hatchability and hatching weight due to exposing quail eggs to low level of gamma radiation as compared to non-exposed eggs. The average body weight and the relative weights of carcass, testis and oviduct, egg production, egg weight, serum total protein, albumin, globulins, RBC, WBC and Hb values were increased significantly (P th week due to adding Lactobacilli and lactose to the basal diet. Significant reduction (P<0.05) in the intestinal wall index was observed due to adding Lactobacilli and lactose to the basal diet of hatched quails. In conclusion, adding Lactobacilli and/or lactose to the basal diet of hatched Japanese quails improved performance as well as blood constituents and intestinal wall index. The magnitude of this improvement was even greater when both supplements were combined. In addition, the exposure of eggs to low level of gamma radiation (50 rad) improved hatchability and hatching weight of Japanese quail eggs, but no relationship to dietary

  13. Dentinal hypersensitivity following scaling and root planing: comparison of low-level laser and topical fluoride treatment.

    Science.gov (United States)

    Pesevska, Snezana; Nakova, Marija; Ivanovski, Kiro; Angelov, Nikola; Kesic, Ljiljana; Obradovic, Radmila; Mindova, Sonja; Nares, Salvador

    2010-09-01

    The aim of this study is to compare the effectiveness of low-level laser irradiation to traditional topical fluoride treatment for treatment choices of dentinal hypersensitivity following scaling and root planing. The experimental group (15 patients) was treated with low-energy-level diode laser at each site of dentinal hypersensitivity following scaling and root planning. The control group (15 patients) received topical fluoride treatment (protective varnish for desensitization). All the patients were treated at baseline visit, and then at day 2 and 4 after the initial treatment; the pain was subjectively assessed by the patients as strong, medium, medium low, low, or no pain. Total absence of the dental hypersensitivity was reported in 26.66% of the examined group even after the second visit, compared to the control group where complete resolution of the hypersensitivity was not present after the second visit in any of the treated cases. Complete absence of pain was achieved in 86.6% of patients treated with laser and only in 26.6% in the fluoride treated group, after the third visit. Based on our findings, we conclude that low-energy biostimulative laser treatment can be successfully used for treatment of dental hypersensitivity following scaling and root planing.

  14. Expression of DMP-1 in the human pulp tissue using low level laser therapy

    International Nuclear Information System (INIS)

    Neto, Natalino Lourenço; Teixeira Marques, Nádia Carolina; Fernandes, Ana Paula; Silva, Thiago Cruvinel; Andrade Moreira Machado, Maria Aparecida; Oliveira, Thais Marchini; Rodini, Camila Oliveira

    2015-01-01

    This study aimed to evaluate the effects of low-level laser therapy (LLLT) on DMP-1 expression in pulp tissue repair of human primary teeth. Twenty mandibular primary molars were randomly assigned into the following groups: Group I—Buckley’s Formocresol (FC); Group II—Calcium Hydroxide (CH); Group III—LLLT + CH and Group IV—LLLT + Zinc oxide/Eugenol. The teeth at the regular exfoliation period were extracted for histological analysis and immunolocalization of DMP-1. Descriptive analysis was performed on the dentin pulp complex. Histopathological assessment showed internal resorption in group FC. Groups CH and LLLT + CH provided better pulpal repair due to the absence of inflammation and the formation of hard tissue barrier. These two groups presented odontoblastic layer expressing DMP-1. According to this study, low level laser therapy preceding the use of calcium hydroxide exhibited satisfactory bio-inductive activity on pulp tissue repair of human primary teeth. However, other histological and cellular studies are needed to confirm the laser tissue action and efficacy. (paper)

  15. In vitro effect of low-level laser on odontoblast-like cells

    International Nuclear Information System (INIS)

    Oliveira, C F; Hebling, J; De Souza Costa, C A; Basso, F G; Lins, E C; Kurachi, C; Bagnato, V S

    2011-01-01

    The aim of this study was to evaluate the metabolism of odontoblast-like MDPC-23 cells subjected to direct LLL irradiation. The cells were seeded (20,000 cells/well) in 24-well plates and incubated for 24 hours at 37deg C. After this period, the culture medium (DMEM) was replaced by fresh DMEM supplemented with 2 or 5% (stress induction by nutritional deficit) or 10% fetal bovine serum (FBS). The cells were exposed to laser doses of 2, 4, 10, 15 and 25 J/cm 2 from a near infrared InGaAsP diode laser prototype (LASERTable; 780±3 nm, 40 mW). One control group (sham irradiation) was established for each experimental condition (laser dose x FBS supplementation). Three and 72 hours after the last irradiation, cells were analyzed with respect to metabolism, morphology, total protein expression and alkaline phosphatase (ALP) activity. Higher metabolism and total protein expression were observed 72 hours after the last irradiation at the doses of 15 and 25 J/cm 2 (Mann-Whitney; p 2 . For the dose of 25 J/cm 2 , the highest ALP activity was observed with 10% FBS. It was concluded that the LLLT parameters used in this study stimulated the metabolic activity of the MDPC-23 cells, especially at the doses of 15 and 25 J/cm 2

  16. EFFICACY OF LOW LEVEL LASER THERAPY IN THE TREATMENT OF ALOPECIA AREATA

    OpenAIRE

    Nermeen Mohamed Abdelhalim. PhD PT

    2014-01-01

    Background: Alopecia areata is a chronic inflammatory disease which affects the hair follicles and sometimes the nails. Purpose: The purpose of this study was to evaluate the efficacy of low level laser therapy in the treatment of alopecia areata of the scalp. Method: Twenty three patients (14 male and 9 female) had 2 or more patches of the scalp, one patch was left for comparison as a control patches. The age ranged from 22 to 39 years with 30 ± 6.09 years mean. The study p...

  17. Pulsed low-level infrared laser alters mRNA levels from muscle repair genes dependent on power output in Wistar rats

    Science.gov (United States)

    Trajano, L. A. S. N.; Trajano, E. T. L.; Thomé, A. M. C.; Sergio, L. P. S.; Mencalha, A. L.; Stumbo, A. C.; Fonseca, A. S.

    2017-10-01

    Satellite cells are present in skeletal muscle functioning in the repair and regeneration of muscle injury. Activation of these cells depends on the expression of myogenic factor 5 (Myf5), myogenic determination factor 1(MyoD), myogenic regulatory factor 4 (MRF4), myogenin (MyoG), paired box transcription factors 3 (Pax3), and 7 (Pax7). Low-level laser irradiation accelerates the repair of muscle injuries. However, data from the expression of myogenic factors have been controversial. Furthermore, the effects of different laser beam powers on the repair of muscle injuries have been not evaluated. The aim of this study was to evaluate the effects of low-level infrared laser at different powers and in pulsed emission mode on the expression of myogenic regulatory factors and on Pax3 and Pax7 in injured skeletal muscle from Wistar rats. Animals that underwent cryoinjury were divided into three groups: injury, injury laser 25 Mw, and injury laser 75 mW. Low-level infrared laser irradiation (904 nm, 3 J cm-2, 5 kHz) was carried out at 25 and 75 mW. After euthanasia, skeletal muscle samples were withdrawn and the total RNA was extracted for the evaluation of mRNA levels from the MyoD, MyoG, MRF4, Myf5, Pax3, and Pax7 gene. Pax 7 mRNA levels did not alter, but Pax3 mRNA levels increased in the injured and laser-irradiated group at 25 mW. MyoD, MyoG, and MYf5 mRNA levels increased in the injured and laser-irradiated animals at both powers, and MRF4 mRNA levels decreased in the injured and laser-irradiated group at 75 mW. In conclusion, exposure to pulsed low-level infrared laser, by power-dependent effect, could accelerate the muscle repair process altering mRNA levels from paired box transcription factors and myogenic regulatory factors.

  18. Effects of low-level laser therapy on burning mouth syndrome.

    Science.gov (United States)

    Valenzuela, S; Lopez-Jornet, P

    2017-02-01

    To investigate low-level laser therapy (LLLT) applied to treat burning mouth syndrome (BMS). This prospective, comparative, partially blinded, single-centre, clinical trial of GaAlAs Laser, with 815 nm wavelength, included 44 BMS patients divided randomly into three groups: Group I (n = 16): GaAlAs laser 815 nm wavelength, 1 W output power, continuous emissions, 4 s, 4 J and fluence rate 133·3 J cm -2 ; Group II (n = 16): GaAlAs infrared laser, 815 nm wavelength, 1 W output power, continuous emissions, 6 s, 6 J and fluence rate 200 J cm -2 ; Group III (n = 12) placebo group, sham laser. All groups received a weekly dose for 4 weeks. Pain intensity was recorded using a 10-cm visual analogue scale; patients responded to the oral health impact profile (OHIP-14), xerostomia severity test and the hospital anxiety-depression scale (HAD). These assessments were performed at baseline, 2 and 4 weeks. LLLT decreased pain intensity and improved OHIP-14 scores significantly from baseline to 2 weeks in groups I and II compared with the placebo group. No statistically significant differences were found from 2 to 4 weeks. Overall improvements in visual analogue scale (VAS) scores from baseline to the end of treatment were as follows: Group I 15·7%; Group II 15·6%; Group III placebo 7·3%. LLLT application reduces symptoms slightly in BMS patients. © 2016 John Wiley & Sons Ltd.

  19. Low-level laser therapy for the treatment of androgenic alopecia: a review.

    Science.gov (United States)

    Darwin, Evan; Heyes, Alexandra; Hirt, Penelope A; Wikramanayake, Tongyu Cao; Jimenez, Joaquin J

    2018-02-01

    There are many new low-level laser technologies that have been released commercially that claim to support hair regrowth. In this paper, we will examine the clinical trials to determine whether the body of evidence supports the use of low-level laser therapy (LLLT) to treat androgenic alopecia (AGA). A literature search was conducted through Pubmed, Embase, and Clinicaltrials.gov for clinical trials using LLLT to treat AGA. Thirteen clinical trials were assessed. Review articles were not included. Ten of 11 trials demonstrated significant improvement of androgenic alopecia in comparison to baseline or controls when treated with LLLT. In the remaining study, improvement in hair counts and hair diameter was recorded, but did not reach statistical significance. Two trials did not include statistical analysis, but showed marked improvement by hair count or by photographic evidence. Two trials showed efficacy for LLLT in combination with topical minoxidil. One trial showed efficacy when accompanying finasteride treatment. LLLT appears to be a safe, alternative treatment for patients with androgenic alopecia. Clinical trials have indicated efficacy for androgenic alopecia in both men and women. It may be used independently or as an adjuvant of minoxidil or finasteride. More research needs to be undertaken to determine the optimal power and wavelength to use in LLLT as well as LLLT's mechanism of action.

  20. Diffuse correlation spectroscopy (DCS) study of blood flow changes during low level laser therapy (LLLT): a preliminary report

    Science.gov (United States)

    Soni, Sagar; Wang, Xinlong; Liu, Hanli; Tian, Fenghua

    2017-02-01

    Photobiomodulation with low-power, high-fluence light in the near-infrared range (600-1100nm), also known as low level laser therapy (LLLT), has been used for promoting healing of wounds, reducing pain, and so on. Understanding its physiological effect is essential for treatment optimization and evaluation. In this study, we used diffuse correlation spectroscopy (DCS) to investigate the changes of regional blood flow in skeletal muscle induced by a single session of LLLT. DCS is an emerging optical modality to probe microvascular blood flow in human tissues in vivo. We have developed a software-based autocorrelator system with the benefits such as flexibility in raw photon count data processing, portability and low cost. LLLT was administered at the human forearm with a 1064-nm, continuous-wave laser. The emitting power was 3.4 W in an area of 13.6 cm2, corresponding to 0.25W/cm2 irradiance. The emitting duration was 10 minutes. Eight healthy adults of any ethnic background, in an age range of 18-40 years old were included. The results indicate that LLLT causes reliable changes in regional blood flow. However, it remains unclear whether these changes are physiological or attributed to the heating effect of the stimulation laser.

  1. Effect of Low-Level Laser therapy on the fungal proliferation of Candida albicans

    Science.gov (United States)

    Carneiro, Vanda S. M.; Araújo, Natália C.; Menezes, Rebeca F. d.; Moreno, Lara M.; Santos-Neto, Alexandrino d. P.; Gerbi, Marleny Elizabeth M.

    2016-03-01

    Candida albicans plays an important role in triggering infections in HIV+ patients. The indiscriminate use of antifungals has led to resistance to Candida albicans, which requires new treatment alternatives for oral candidiasis. Low-level laser therapy promotes a considerable improvement in the healing of wounds and in curing illnesses caused by microorganisms. The aim of the present study was to assess the effect of laser radiation on the cell proliferation of Candida albicans in immunosuppressed patients. Six Candida albicans strains that had been isolated from immunosuppressed patients were divided into a control group and experimental groups, which received eight sessions of laser therapy (InGaAlP, λ685nm, P = 30mW, CW, Φ~6 mm and GaAlAs, λ830nm, P = 40mW, CW, Φ~6 mm) using dosimetries of 6J/cm2, 8J/cm2, 10J/cm2 and 12J/cm2 for each wavelength and power. The results were not statistically significant (Kruskal Wallis, p > 0.05), although the proliferation of Candida albicans was lower in some of the experimental groups. The dosimetry of 6J/cm2 (GaAlAs, λ830nm, P = 40mW) provided lower mean scores than the other groups for the growth of Candida. Further studies are required to confirm whetehr laser therapy is a viable option in the treatment of fungal infections.

  2. Effects of low level laser in the morphology of the skeletal muscle fiber during compensatory hypertrophy in plantar muscle of rats

    Science.gov (United States)

    Terena, Stella Maris Lins; Fernandes, Kristianne Porta Santos; Kalil, Sandra; Alves, Agnelo Neves; Mesquita Ferrari, Raquel Agnelli

    2015-06-01

    The hypertrophy is known as an increase the cross-sectional area of the muscle as a result of a muscular work against an overload, and it is compensatory because the overload is induced by functional elimination of synergistic muscles. The importance of study the compensatory hypertrophy is understand how this process can be influenced by the irradiation with regard to the weight and muscle cross-sectional area, to assist in the rehabilitation process and the effectiveness functional return. The aim was evaluate the effects of low-level laser irradiation on morphological aspects of muscle tissue, comparing the weight and cross-sectional area in rat skeletal muscle. Wistar rats were divided into three groups: control, hypertrophy group without irradiation (right plantar muscle) and hypertrophy group and irradiation (left plantar muscle), both analyzed after 7 and 14 days. The irradiation was performed daily immediately after the surgery. The parameters were: λ = 780nm, beam spot of 0.04 cm2, output power of 40mW, power density of 1W/cm2, energy density of 10J / cm2 and 10s exposure time with a total energy of 3.2 J. The results revealed that low level laser irradiation an increase the weight of the plantaris muscle after 7 and 14 days with a difference of 7.06% and 11.51% respectively. In conclusion, low level laser irradiation has an effect on compensatory hypertrophy to produce increased muscle weight and promoted an increase in cross-sectional area of muscle fibers in the compensatory hypertrophy model after 14 days with parameters cited above.

  3. The effects of low level laser therapy on both HIV-1 infected and uninfected TZM-bl cells

    CSIR Research Space (South Africa)

    Lugongolo, Masixole Y

    2017-01-01

    Full Text Available that would completely eradicate the virus in infected individuals, the quest for new therapies continues. Low level laser therapy (LLLT) involves the exposure of cells to low levels of red or infrared light. LLLT has been widely used in different medical...

  4. Effect of low-level laser therapy after extraction of impacted lower third molars.

    Science.gov (United States)

    Ferrante, Maurizio; Petrini, Morena; Trentini, Paolo; Perfetti, Giorgio; Spoto, Giuseppe

    2013-05-01

    The aim of this study is to evaluate the effectiveness of the low-level laser therapy (LLLT) in the control of pain, swelling, and trismus associated with surgical removal of impacted lower third molars. Thirty patients were randomized into two treatment groups, each with 15 patients-group test (LLLT) and a group control (no-LLLT)-and were told to avoid any analgesics 12 h before the procedure. In group test, the 980-nm diode-laser (G-Laser 25 Galbiati, Italy) was applied, using a 600-μm handpiece, intraorally (lingual and vestibular) at 1 cm from the involved area and extraoral at the insertion point of the masseter muscle immediately after surgery and at 24 h. The group control received only routine management. Parameters used for LLLT were: continuous mode, at 300 mW (0.3 W) for a total of 180 s (60 s × 3) (0.3 W × 180 s=54 J). Group test showed improvement in the interincisal opening and remarkable reduction of trismus, swelling and intensity of pain on the first and the seventh postoperative days. Although LLLT has been reported to prevent swelling and trismus following the removal of impacted third molars, some of these studies reported a positive laser effect while others did not. All references to the use of laser therapy in the postoperative management of third molar surgery employ different methodologies and, in some, explanations as to selection of their respective radiation parameters are not given. This study has demonstrated that LLLT, with these parameters, is useful for the reduction of postoperative discomfort after third-molar surgery.

  5. Low-level laser therapy: Case-control study in dogs with sterile pyogranulomatous pododermatitis

    Directory of Open Access Journals (Sweden)

    Roberta Perego

    2016-08-01

    Full Text Available Aim: Low-level laser therapy (LLLT is a therapeutic photobiostimulation with properties in reducing swelling, inflammation, and promoting tissue healing. The objective of this pilot study was to evaluate LLLT in sterile pyogranulomatous pododermatitis in five dogs. Materials and Methods: In each dog, one lesion was designated as the control (treated with a 0.0584% hydrocortisone aceponate spray, and one or more other lesions were treated with a gallium aluminum arsenide-laser, daily for 5 days. Lesions were scored before treatment (D0, at the end (D4, 16 days after the last laser treatment (D20, and after 2 months (D65. Results: Comparing the treated lesion group with the control lesion group, the clinical score was similar at D0, whereas there was a statistically significant difference at D4 and D20; in the treated group over time, there was a statistically significant improvement between D0, D4, and D20. Lesion recurrence was absent in more than 50% of the treated lesions at D65. No adverse reactions were reported. Conclusion: Given the positive results of this first clinical study, it would be interesting to extend the study to confirm the validity of this type of therapy in sterile pyogranulomatous pododermatitis in the dog.

  6. Cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser.

    Science.gov (United States)

    Alexsandra da Silva Neto Trajano, Larissa; da Silva, Camila Luna; de Carvalho, Simone Nunes; Cortez, Erika; Mencalha, André Luiz; de Souza da Fonseca, Adenilson; Stumbo, Ana Carolina

    2016-07-01

    Low-level infrared laser is considered safe and effective for treatment of muscle injuries. However, the mechanism involved on beneficial effects of laser therapy are not understood. The aim was to evaluate cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser at therapeutic fluences. C2C12 myoblast cultures at different (2 and 10 %) fetal bovine serum (FBS) concentrations were exposed to low-level infrared laser (808 nm, 100 mW) at different fluences (10, 35, and 70 J/cm(2)) and evaluated after 24, 48, and 72 h. Cell viability was evaluated by WST-1 assay; reactive oxygen species (ROS), apoptosis, and necrosis were evaluated by flow cytometry. Cell viability was decreased atthe lowest FBS concentration. Laser exposure increased the cell viability in myoblast cultures at 2 % FBS after 48 and 72 h, but no significant increase in ROS was observed. Apoptosis was decreased at the higher fluence and necrosis was increased at lower fluence in myoblast cultures after 24 h of laser exposure at 2 % FBS. No laser-induced alterations were obtained at 10 % FBS. Results show that level of reactive oxygen species is not altered, at least to those evaluated in this study, but low-level infrared laser exposure affects cell viability, apoptosis, and necrosis in myoblast cultures depending on laser fluence and physiologic conditions of cells.

  7. Low-level laser therapy equipment needs calibration before clinical use

    Science.gov (United States)

    Machado de Senna, André; Machado-de-sena, Rosa Maria; Facundes, Arseni Lázaro; Barros Nepomuceno, Patrícia; Sávya Florentino, Wanilza; Olegário de Araújo, Ronyere

    2018-04-01

    Many factors can influence the radiant power delivered by the low-level laser therapy (LLLT) equipment, such as its cleaning and condition, as well as the use of plastic films for protecting the laser or even its time of use. Radiant power is an important factor to consider because it affects the amount of energy delivered to the target tissue. The difference between real radiant power (RRP) and nominal radiant power (NRP) may interfere in the expected results, because the delivered energy is different from the desired energy. Purpose: The objective of this study was to compare the NRP with the RRP offered by LLLT devices under clinical conditions of use. Material and Methods: For data collection to this study, 61 LLLT devices used in private and public dental practices in the state of Tocantins, Brazil, were evaluated. Three consecutive power measurements were performed at one-minute intervals and then the average of the measured power was calculated. The RRP was compared to the NRP. Results: The equipment presented NRP from 30 to 500mW while RRP ranged from 17.3 to 107.0mW. Discussion and Conclusion: The mean power measured in clinical conditions of use of the laser equipment was different from the nominal power reported by the manufacturers of the devices (p<0,01). The RRP ranged between 12.92% and 107% of NRP. This fact is worrisome, since one of the most important parameters for the success of the treatment of an injury using LLLT is the energy (power x time) delivered. These findings reinforce the need of calibrating the equipment before each laser application in order to avoid failures in the therapeutic conduct.

  8. Low-level laser therapy of myofascial pain syndromes of patients with osteoarthritis of knee and hip joints

    Science.gov (United States)

    Gasparyan, Levon V.

    2001-04-01

    The purpose of the given research is the comparison of efficiency of conventional treatment of myofascial pain syndromes of patients with osteoarthritis (OA) of hip and knee joints and therapy with additional application of low level laser therapy (LLLT) under dynamic control of clinical picture, rheovasographic, electromyographic examinations, and parameters of peroxide lipid oxidation. The investigation was made on 143 patients with OA of hip and knee joints. Patients were randomized in 2 groups: basic group included 91 patients, receiving conventional therapy with a course of LLLT, control group included 52 patients, receiving conventional treatment only. Transcutaneous ((lambda) equals 890 nm, output peak power 5 W, frequency 80 - 3000 Hz) and intravenous ((lambda) equals 633 nm, output 2 mW in the vein) laser irradiation were used for LLLT. Studied showed, that clinical efficiency of LLLT in the complex with conventional treatment of myofascial pain syndromes at the patients with OA is connected with attenuation of pain syndrome, normalization of parameters of myofascial syndrome, normalization of the vascular tension and parameters of rheographic curves, as well as with activation of antioxidant protection system.

  9. Low-level laser therapy with 940 nm diode laser on stability of dental implants: a randomized controlled clinical trial.

    Science.gov (United States)

    Torkzaban, Parviz; Kasraei, Shahin; Torabi, Sara; Farhadian, Maryam

    2018-02-01

    Low-level laser therapy (LLLT) is a non-invasive modality to promote osteoblastic activity and tissue healing. The aim of this study was to evaluate the efficacy of LLLT for improvement of dental implant stability. This randomized controlled clinical trial was performed on 80 dental implants placed in 19 patients. Implants were randomly divided into two groups (n = 40). Seven sessions of LLLT (940 nm diode laser) were scheduled for the test group implants during 2 weeks. Laser was irradiated to the buccal and palatal sides. The same procedure was performed for the control group implants with laser hand piece in "off" mode. Implant stability was measured by Osstell Mentor device in implant stability quotient (ISQ) value immediately after surgery and 10 days and 3, 6, and 12 weeks later. Repeated measures ANOVA was used to compare the mean ISQ values (implant stability) in the test and control groups. Statistical test revealed no significant difference in the mean values of implant stability between the test and control groups over time (P = 0.557). Although the mean values of implant stability changed significantly in both groups over time (P laser group in the first weeks and increased from the 6th to 12th week, LLLT had no significant effect on dental implant stability.

  10. Low level laser therapy (photobiomodulation) for the management of breast cancer-related lymphedema: an update

    Science.gov (United States)

    Baxter, G. David; Liu, Lizhou; Chapple, Cathy; Petrich, Simone; Anders, Juanita J.; Tumilty, Steve

    2018-04-01

    Breast cancer related lymphedema (BCRL) is prevalent among breast cancer survivors, and may be painful and disfiguring with associated psychological impact. Previous research shows increasing use of low level laser therapy (LLLT), now commonly referred to as photobiomodulation (PBM) therapy for managing BCRL, in countries including the United States and Australia. However, conclusions were limited by the paucity, heterogeneity, and poor quality of previous studies. LLLT (PBM) has been barely used in clinical practice in New Zealand, and no clinical studies on LLLT (PBM) for BCRL have been conducted in this country. In order to promote this potentially useful treatment modality for BCRL patients, the Laser Lymphedema Trial Team at the University of Otago conducted a program to assess the effectiveness of LLLT (PBM) in management of BCRL. The program comprises three phases including a systematic review (completed), a feasibility study (completed), and a full-scale randomized controlled trial (proposed). This current paper provides an update on the program. Based upon the systematic review, LLLT (PBM) is considered a potentially effective treatment approach for women with BCRL; the review also indicated the need for further research including exploration of the relevance of dosage and other LLLT (PBM) parameters. The feasibility study demonstrated that it is feasible to conduct a fully powered RCT to definitively test the effectiveness of the additional use of LLLT (PBM) in the management of BCRL, and 114 participants will be needed at baseline in the main study. Currently, the full-scale RCT is under preparation.

  11. Treatment of bronchial asthma with low-level laser in attack-free period at children

    Science.gov (United States)

    Ailioaie, C.; Ailioaie, Laura

    2000-06-01

    Bronchial asthma is a common disease in both the pediatric and adult populations, characterized by wide variations over short periods of time in resistance to airflow in intrapulmonary airways. A primary goal in the use of low- level laser therapy (LLLT) was the safe, effective and rapid palliation of symptoms owing to tracheal or bronchial obstruction. We have investigated the effects of LLLT comparatively with other modality trials in children's asthma. In the study were included 98 patients aged 10-18 years diagnosed with moderate or severe asthma, in attack- free period. The patients were divided into 3 groups. Group 1 received only laser therapy using extra meridian acupuncture points and scanning technique. Group 2 was treated only with inhaled Serevent 2 X 25 micrometers , two times daily, 3 months. Group 3 was tread with Theophylline retard in dosage of 15-mg/kg/12 h, 3 months. At the end of treatment we remarked a noticeable improvement of the clinical, functional and immunological characteristics at 83 percent of patients in group 1, comparatively with only 70 percent (group 2) and 53 percent (group 3). The LLLT had a very good action on bronchial patency , displayed an immunocorrecting action and is recommended in attack-free periods at children.

  12. Effect of 940 nm low-level laser therapy on osteogenesis in vitro

    Science.gov (United States)

    Jawad, Mohammed Mahmood; Husein, Adam; Azlina, Ahmad; Alam, Mohammad Khursheed; Hassan, Rozita; Shaari, Rumaizi

    2013-12-01

    Bone regeneration is essential in medical treatment, such as in surgical bone healing and orthodontics. The aim of this study is to examine the effect of different powers of 940 nm diode low-level laser treatment (LLLT) on osteoblast cells during their proliferation and differentiation stages. A human fetal osteoblast cell line was cultured and treated with LLLT. The cells were divided into experimental groups according to the power delivered and periods of exposure per day for each laser power. The (3-(4,5-dimethylthiazol-2yl)-2,5 diphenyl tetrazolium bromide) (MTT) assay was used to determine cell proliferation. Both alkaline phosphatase and osteocalcin activity assays were assessed for cell differentiation. All treatment groups showed a significant increase in cell proliferation and differentiation compared to the control group. Regarding the exposure time, the subgroups treated with the LLLT for 6 min showed higher proliferation and differentiation rates for the powers delivered, the 300-mW LLLT group significantly increased the amount of cell proliferation. By contrast, the 100 and 200 mW groups showed significantly greater amounts of cell differentiation. These results suggest that the use of LLLT may play an important role in stimulating osteoblast cells for improved bone formation.

  13. Could low level laser therapy and highly active antiretroviral therapy lead to complete eradication of HIV-1 in vitro?

    CSIR Research Space (South Africa)

    Lugongolo, Masixole Y

    2017-01-01

    Full Text Available used to treat different medical conditions such as diabetic wounds, sports injuries and others. The technique involves exposure of cells or tissue to low levels of red and near infrared laser light. Both HIV infected and uninfected cells were laser...

  14. The Effect of Low Level Laser Therapy on Some Plasma Ions Concentration

    Directory of Open Access Journals (Sweden)

    Nadia H. Sahib

    2017-12-01

    Full Text Available Low level laser therapy (LLLT has variousapplications in clinical pathology.It has been found to be efficient in acceleration of wound healing, enhanced remodeling and bone repair, regeneration of neural cells following injury, pain attenuation, endorphin release stimulation and modulation of immune system. The possible intracellular sequence of events after treatment with LLLT, include induction of oxidative phosphorylation with increased enzymatic activity, increased expression of certain cytosolic enzymes and enhanced activity of intracellular organelles. A broad range of eukaryotic proteins require posttranslational modifications such as phosphorylation, glycosylation, or signal peptide cleavage to display full functional activity. Eukaryotic cell-free expression systems provide the possibility to synthesize eukaryotic proteins with posttranslational modifications and are especially useful forexpression and analysis of human proteins with native structure and function.The stimulated mechanism involves protein- to-protein interaction, where two or more proteins bind together to facilitate molecular processes, including modification of proteins by members of small ubiquitin- related modifier proteins (SUMOand also protein phosphorylation and tyrosination. The consequence of laser application in treatment, can be seen as influencing the transmission of intracellular signals via an integrated and rapid modulation of ion channels, achieved through both direct action on photo-acceptors (such as cytochrome c-oxidase and through indirect modulation via enzymes,including tyrosine hydroxylase (TH, tyrosine kinases and tyrosine kinasereceptors. This exogenous action then facilitates an existing photonic biomodulation mechanism with the body, and initiates ion channel modulation both in the periphery and the central nervous system (CNS. Evidence indicates that the ion channel modulation functions predominately through the potassium channels, including

  15. Effect of low-level laser therapy on wound healing after depigmentation procedure: A clinical study

    Directory of Open Access Journals (Sweden)

    Kirti Chawla

    2016-01-01

    Full Text Available Aim: The aim of the present study is to evaluate and compare the effects of low-level laser therapy (LLLT on wound healing after depigmentation procedure. Materials and Methods: In this study, 12 patients with bilateral melanin hyperpigmentation were treated with surgical stripping using a blade. After completion of the surgical process and bleeding stasis, any of the symmetrical surgical sites was randomly assigned for LLLT (test site using a defocused diode laser at 1 mm distance for 5 min. After every laser exposure, the surgical site was coated with plaque disclosing solution (erythrosine on the 3rd, 7th, and 15th day. A photograph of the surgical site was taken using a Digital SLR Camera, which was placed at 30 cm distance at 55 mm zoom, 1/100 shutter speed, f 14 aperture size, and ISO 4000 with a ring flash. The area of the stained parts of the photographs was evaluated using image analysis software. Results: At day 3, test site showed 1.26 ± 0.23 mm2 and control site showed 1.45 ± 0.21 mm2 stain uptake by the tissue which was statistically significant. At day 7 and day 15, the test sites exhibited 1.24 ± 0.30 mm2 and 1.12 ± 0.25 mm2 stain uptake, whereas the control site showed 1.37 ± 25 mm2 and 1.29 ± 0.28 mm2 staining, respectively, which were not statistically significant. Conclusion: Within the limitations of this study, the findings revealed that LLLT promotes wound healing after depigmentation procedure until the 3rd day. On the 7th and 15th day, the difference in healing was not statistically significant.

  16. Approach and potentiality of low level laser therapy in veterinary medicine

    Science.gov (United States)

    Paterniani, Valentina; Grolli, Stefano

    2018-04-01

    The Low Level Laser Therapy (LLLT) is an innovative and increasing therapeutic technique in Veterinary Medicine. As in Human Medicine, the low power red/near-infrared laser light could be used to reduce inflammatory conditions, induce analgesia and promote damaged tissues repair, both in conventional animals like horses, dogs and cats and in unconventional ones, including reptiles, birds and exotic mammals. Since A.Eistein (1917) and E.Mester (1968) built its physical and biochemical fundamentals, a growing number of researches, over the years, have expanded the knowledge of the molecular process considered today at the basis of the macroscopic therapeutic effects. Producing a photochemical tissue interaction, laser light is absorbed by the mitochondrial respiratory chain stimulating the generation of ATP, ROS and NO; this determines a modulation in gene expression of proteins playing key roles in cellular processes as tissue repair, inflammatory response and pain control. Different animal pathological conditions could significantly benefit from this therapy, such as acute/chronic muscle-skeletal disorders, dental afflictions, dermatitis, otitis, stomatitis and different kind of skin lesions, as traumatic or post-operative ones. Furthermore, other significant applications are developing scientifically: the treatment of internal organ diseases, the regenerative effects on nervous tissue and the possibility of a beneficial cell-specific cytotoxicity, relevant for oncological cases, are some of these. A high-quality research is therefore crucial for this quickly expanding field of Veterinary Medicine, in order to find the most effective protocols and the ideal doses for each pathological conditions, aiming to always ensure the best and up-todate animal care.

  17. Lifespan studies on different strains of mice exposed chronically to low levels of whole body gamma irradiation

    International Nuclear Information System (INIS)

    Fox, L.A.; Klein, A.K.; Cain, G.R.; Rosenblatt, L.S.

    1982-01-01

    Several strains of mice, chosen for their predisposition to immunohematological disorders, were exposed to low levels of 60 irradiation continuously for four weeks. All individuals were subsequently followed throughout their lifetimes. W/W/sup v/ mice, which are tyically subject to a stem cell deficiency, had a lower cumulative survival rate for the irradiated group than for the unirradiated controls. Irradiated RF/sub j/ mice had a dramatically lower cumulative survival rate than their unirradiated controls. Conversely, BXSB mice, which have a lumphoproliferative autoimmune disorder, had a higher cumulative survival rate after chronic irradiation than did unirradiated BXSBs. Irradiation had no effect upon the survival rate curves of the NZB strain, the murine model for Lupus Erythematosus

  18. The Effect of One Session Low Level Laser Therapy of Extracted Follicular Units on the Outcome of Hair Transplantation.

    Science.gov (United States)

    Tabaie, Seyed Mehdi; Berenji Ardestani, Hoda; Azizjalali, Mir Hadi

    2016-01-01

    Photobiostimulation with low level laser (LLL) has been used in medicine for a long time and its effects have been shown in many diseases. Some studies have evaluated the effect of LLL on androgenic alopecia. One of the most important limitations of the use of LLL in the treatment of alopecia is the requirement for multiple sessions, which is hardly accepted by patients. This study was conducted to evaluate the effect of the irradiation of extracted follicular hair units by LLL on the outcome of hair transplantation. We enrolled 10 patients with androgenic alopecia and after screening tests for infections and other diseases, we extracted hair follicular units. The hair units were divided in two groups. One group was irradiated by LLL 20 minutes before transplantation (660 nm, 80 Hz, 100 mW) and the other one was used as control. The containing plates were labeled as A and B and sent to the operation room. The surgeon was unaware of the therapy assigned to the plates and transplanted them randomly on the right or left side of the head. One hundred follicular units on each sides of the scalp were transplanted symmetrically. The follicles on both sides were evaluated at 3 and 6 months of transplantation for hair growth rate by another physician, blinded to the treatment assigned to each side. Ten patient with androgenic alopecia and mean (SD) age of 31.5 (6.6) years (range 25-45 years) completed the study. All patients had 100% hair growth at 3 and 6 months follow-up except one who had hair growth of 20% at three months of transplantation, which changed to 100% at sixth months. There was no significant difference between the groups regarding hair growth (P > 0.8). One session of LLL irradiation has no significant effect on the outcome of transplanted hair follicles. Studies with larger sample size are needed to draw a definite conclusion.

  19. Effect of low-level laser therapy on radiotherapy-induced hyposalivation and xerostomia: a pilot study.

    Science.gov (United States)

    Saleh, Jamil; Figueiredo, Maria Antonia Zancanaro; Cherubini, Karen; Braga-Filho, Aroldo; Salum, Fernanda Gonçalves

    2014-10-01

    The present pilot study aimed to assess the effect of low-level laser therapy (LLLT) on hyposalivation and xerostomia as a consequence of head and neck radiotherapy. The benefits of LLLT in salivary flow have been shown; however, there are no studies investigating its effects on patients who have already undergone radiotherapy and present hyposalivation and xerostomia as a sequela. Twenty-three patients with a history of head and neck malignancy, who were treated by fractioned teletherapy (dosimetry ranging from 45 to 70 Gy) in the cervicofacial region were selected. They all presented with xerostomia and severe hyposalivation. Patients were randomly distributed into a laser group (n=12) and a control group (n=11). A GaAlAs laser (830 nm, 100 mW, illuminated area 0.028 cm2, 3.57 W/cm2, 20 sec, 2.0 J, 71 J/cm2) was used punctually in the major salivary glands, twice a week for 6 weeks, with a 12 session total. Stimulated and unstimulated salivary flow rate (SFR) were assessed, as well as the xerostomia and quality of life related to oral health (QLROH). The analysis did not show any significant difference between the groups with regards to the SFR and xerostomia, and the QLROH. However, at the end of the treatment, the xerostomia and the QLROH showed significant improvement in both groups compared with assessments performed at baseline, highlighting the importance of advice given to the irradiated patients, and their follow-up. With the parameters used, LLLT was not able to increase SFR or decrease xerostomia. The results may be associated with the late effects of radiotherapy on glandular structure, such as fibrosis and acinar atrophy.

  20. Effects of low-level gamma irradiation on the characteristics of fermented pork sausage during storage

    International Nuclear Information System (INIS)

    Kim, I.S.; Jo, C.; Lee, K.H.; Lee, E.J.; Ahn, D.U.; Kang, S.N.

    2012-01-01

    The effect of gamma irradiation (0.5, 1, 2, and 4 kGy) on the quality of vacuum-packaged dry fermented sausages during refrigerated storage was evaluated. At Day 0 of irradiation, the pH, redness (CIE a ⁎ ), yellowness (CIE b ⁎ ), 2-thiobarbituric acid-reactive substances (TBARS) and volatile basic nitrogen (VBN) values of samples irradiated at 2 and 4 kGy were higher (p ⁎ values (lightness) were lower than those of the non-irradiated control (p ⁎ , CIE a ⁎ and CIE b ⁎ -value of samples were not significantly influenced by irradiation. The CIE a ⁎ , and CIE b ⁎ -values of samples irradiated at 2 and 4 kGy decreased with the increase of storage time. The VBN, TBARS, and CIE L ⁎ -values of samples irradiated at 4 kGy were not changed significantly during refrigerated storage for 90 days (p>0.05). The total plate counts (TPC) and lactic acid bacteria (LAB) in the samples irradiated at 4 kGy were significantly lower (p<0.01) than those with lower irradiation doses. At the end of storage, the TPC, coliform, and LAB in the samples were not increased after irradiation at 1, 0.5 and 1 kGy, respectively. TPC and LAB were not detected in samples irradiated at 4 kGy at Day 90. In addition, no coliform bacteria were found in samples irradiated at 1 kGy during refrigerated storage. Sensory evaluation indicated that the rancid flavor of samples irradiated at 4 kGy was significantly higher, but aroma and taste scores were lower than those of the control at Day 3 of storage. Irradiation of dry fermented sausages at 2 kGy was the best conditions to prolong the shelf-life and decrease the rancid flavor without significant quality deterioration. - Highlights: ► Effect of gamma irradiation on the quality of vacuum-packaged dry fermented sausages during refrigerated storage was evaluated. ► At Day 90, the TPC, coliform, and LAB in the dry fermented sausages were not increased after irradiation at 2, 0.5 and 4 kGy, respectively. ► TPC and LAB were not detected in

  1. Low Level Laser Therapy for the Treatment of Diabetic Foot Ulcers: A Critical Survey

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    Kathrin H. Beckmann

    2014-01-01

    Full Text Available Diabetic foot ulcers as one of the most common complications of diabetes mellitus are defined as nonhealing or long-lasting chronic skin ulcers in diabetic patients. Multidisciplinary care for the diabetic foot is common, but treatment results are often unsatisfactory. Low level laser therapy (LLLT on wound areas as well as on acupuncture points, as a noninvasive, pain-free method with minor side effects, has been considered as a possible treatment option for the diabetic foot syndrome. A systematic literature review identified 1764 articles on this topic. Finally, we adopted 22 eligible references; 8 of them were cell studies, 6 were animal studies, and 8 were clinical trials. Cell studies and animal studies gave evidence of cellular migration, viability, and proliferation of fibroblast cells, quicker reepithelization and reformed connective tissue, enhancement of microcirculation, and anti-inflammatory effects by inhibition of prostaglandine, interleukin, and cytokine as well as direct antibacterial effects by induction of reactive oxygen species (ROS. The transferral of these data into clinical medicine is under debate. The majority of clinical studies show a potential benefit of LLLT in wound healing of diabetic ulcers. But there are a lot of aspects in these studies limiting final evidence about the actual output of this kind of treatment method. In summary, all studies give enough evidence to continue research on laser therapy for diabetic ulcers, but clinical trials using human models do not provide sufficient evidence to establish the usefulness of LLLT as an effective tool in wound care regimes at present. Further well designed research trials are required to determine the true value of LLLT in routine wound care.

  2. New Treatment Applying Low Level Laser Therapy for Acute Dehiscence Saphenectomy in Post Myocardial Revascularization.

    Science.gov (United States)

    Pinto, Nathali Cordeiro; Shoji, Nara; Junior, Mauro Favoretto; Muramatso, Mikiya; Chavantes, Maria Cristina; Stolf, Noedir A. G.

    2008-04-01

    Introduction: In Brazil, the main cause of death is the coronary heart disease and the surgical treatment applied in such cases is the Myocardial Revascularization (MR). Patients undergoing to MR through saphenous vein bypass development dehiscence in 10% of the cases. Dehiscence of surgical incision through Biomodulation treatment with Low Level Laser Therapy (LLLT) in patients who underwent to MR seems to be an unprecedented new therapy and a less invasive technique, which can benefit patients and Institutions, reducing costs. Methodology: It was analyzed 7 diabetic patients, mean age 51, 8 years old that post MR surgery presented dehiscence of the saphenectomy incision on lower limb with erithema, edema and pain. The wounds area varies from 2,2 until 34,8 cm and deep from 0,1 until 1,1 cm. It was used only Diode Laser C.W. (655 nm wavelength), Power = 25 mW, Time = 30 s, Fluence = 4 J/cm2 applied punctually around surgical wound's sore, by 2 cm distance. Results: It was observed granulated tissue all around the incision, as well as decreased inflammatory process, reduction fibrin and wound's size, besides analgesic effect since the first application. It was required in superficial wounds only 3 applications, while in the extensive wounds 8-10 applications were necessary. The LLLT has shown a remarkable role as a wound healing facilitated agent, reflecting the reduction of inflammatory process and improving analgesia. Conclusion: LLLT assisted dehiscence post saphenectomy showed a substantial improvement to the patient's quality of life, with a cost-effectiveness treatment that can benefit both patients and Institutions as an effective and less invasive therapy.

  3. Low-level laser therapy as a treatment for androgenetic alopecia.

    Science.gov (United States)

    Afifi, Ladan; Maranda, Eric L; Zarei, Mina; Delcanto, Gina M; Falto-Aizpurua, Leyre; Kluijfhout, Wouter P; Jimenez, Joaquin J

    2017-01-01

    Androgenetic alopecia (AGA) affects 50% of males by age 50 and 50% of females by age 80. Recently, the use of low-level laser therapy (LLLT) has been proposed as a treatment for hair loss and to stimulate hair regrowth in AGA. This paper aims to review the existing research studies to determine whether LLLT is an effective therapy for AGA based on objective measurements and patient satisfaction. A systematic literature review was done to identify articles on Medline, Google Scholar, and Embase that were published between January 1960 and November 2015. All search hits were screened by two reviewers and examined for relevant abstracts and titles. Articles were divided based on study design and assessed for risk of bias. Eleven studies were evaluated, which investigated a total of 680 patients, consisting of 444 males and 236 females. Nine out of 11 studies assessing hair count/hair density found statistically significant improvements in both males and females following LLLT treatment. Additionally, hair thickness and tensile strength significantly improved in two out of four studies. Patient satisfaction was investigated in five studies, and was overall positive, though not as profound as the objective outcomes. The majority of studies covered in this review found an overall improvement in hair regrowth, thickness, and patient satisfaction following LLLT therapy. Although we should be cautious when interpreting these findings, LLLT therapy seems to be a promising monotherapy for AGA and may serve as an effective alternative for individuals unwilling to use medical therapy or undergo surgical options. Lasers Surg. Med. 49:27-39, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Preliminary study on radio-chemo-induced oral mucositis and low level laser therapy

    Science.gov (United States)

    Merigo, Elisabetta; Fontana, Matteo; Fornaini, Carlo; Clini, Fabio; Cella, Luigi; Vescovi, Paolo; Oppici, Aldo

    2012-09-01

    Background: Oral mucositis remains one of the most common and troubling side effects of antineoplastic radiation and drug therapy: its incidence in onco-hematological radio-chemotreated patients is variable between 50 and 100% and its impact on this populations is directly linked with the experience of intense pain causing reduction and modification of therapy regimens, decreased survival rates and increased cost of care. Purpose: Aim of this study is the preliminary evaluation of a Low Level Laser therapy (LLLT) protocol on healing process of oral mucositis and on pain and quality of life of patients experiencing this dramatic side-effect. Materials and methods: Patients were evaluated and treated at the Unita` Operativa Semplice Dipartimentale di Odontostomatologia e Chirurgia Maxillo-Facciale of the Hospital of Piacenza were they were treated for primary disease with protocols of chemotherapy and/or radiotherapy. LLLT protocol was performed with a diode laser (808 nm -XD Smile - Fotona -Slovenia) on a two weeks-6 treatments schedule with power of 0.5 W and application of 30 seconds. Mucositis grading was scored on the basis of WHO classification by two blind operators at each treatment and at 1 and 2 weeks after treatment. Pain and capability of deglutition were described by patients by means questionnaires based on Visual Analogue Scale, Numerical Rating Scale and Quality of Life. Results: A relevant improvement of healing of oral mucositis, in terms of reduction of grading score, and of pain, swallowing discomfort and quality of life was recorded. Discussion and conclusion: Results of this preliminary study are encouraging for the realization of larger studies focused on the application of LLLT protocols in management of radio-chemotreated patients with oral mucositis.

  5. Pilot study in neonates using low-level laser therapy in the immediate postoperative period of myelomeningocele

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    Nathali Cordeiro Pinto

    2010-03-01

    Full Text Available Objective: To analyze the tissue repair behavior after corrective surgical incision in neonates submitted to low-level laser therapy, in an attempt to diminish the incidence of postoperative dehiscence following the surgery for myelomeningocele performed immediately after birth. Methods: It is a prospective pilot study with 13 myelomeningocele patients submitted to surgery at birth who received adjuvant treatment with low-level laser therapy (Group A. Diode laser C.W., λ = 685t nm, p = 21 mW, E = 0.19 J was punctually applied along the surgical incision, summing up 4 to 10 J energy delivered per patient, according to the surgical wound area and, then, compared with the previous results, which were obtained from 23 patients undergoing surgery without laser therapy (Group B. Results: This pilot study showed a significant decline in dehiscence of surgical wounds in neonates submitted to low-level laser therapy as compared to controls (7.69 versus 17.39%, respectively, demonstrating this is an effective, safe and noninvasive treatment method. Conclusion: This new adjuvant therapeutic proposal with low-level laser therapy aided healing of surgical wounds, preventing morbidities, as well as decreasing hospital stay, which implies cost of reduction for patients and for the institution.

  6. TP53 and ATM mRNA expression in skin and skeletal muscle after low-level laser exposure.

    Science.gov (United States)

    Guedes de Almeida, Luciana; Sergio, Luiz Philippe da Silva; de Paoli, Flavia; Mencalha, Andre Luiz; da Fonseca, Adenilson de Souza

    2017-08-01

    Low-level lasers are widespread in regenerative medicine, but the molecular mechanisms involved in their biological effects are not fully understood, particularly those on DNA stability. Therefore, this study aimed to investigate mRNA expression of genes related to DNA genomic stability in skin and skeletal muscle tissue from Wistar rats exposed to low-level red and infrared lasers. For this, TP53 (Tumor Protein 53) and ATM (Ataxia Telangiectasia Mutated gene) mRNA expressions were evaluated by real-time quantitative PCR (RT-qPCR) technique 24 hours after low-level red and infrared laser exposure. Our data showed that relative TP53 mRNA expression was not significantly altered in both tissues exposed to lasers. For ATM, relative mRNA expression in skin tissue was not significantly altered, but in muscle tissue, laser exposure increased relative ATM mRNA expression. Low-level red and infrared laser radiations alter ATM mRNA expression related to DNA stability in skeletal muscle tissue.

  7. Effects of low level laser therapy and high voltage stimulation on diabetic wound healing

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    María Cristina Sandoval Ortíz

    2014-08-01

    Full Text Available Background: a review of the literature found no clinical studies in which low level laser therapy (LLLT and high voltage pulsed current (HVPC were compared to evaluate their effectiveness in promoting wound healing. Objective: The purpose of this study was compare the effects of LLLT, HVPC and standard wound care (SWC on the healing of diabetic foot ulcers. Methods: randomized controlled clinical trial where diabetic patients were divided in control group (CG treated with SWC; HVPC group received HVPC plus SWC; LLLTgroup, treated with LLLT plus SWC. HVPC was applied 45min, 100pps and 100μs. LLLTparameters were 685nm, 30mW,2J/cm² applied to the wound edges and 1,5J/cm² in the wound bed. All subjects were treated 16 weeks or until the wound closed. The variables were healing, healing proportion, ulcers's characteristics, protective sensation, nerve conduction studies (NCS and quality life. ANCOVA analysis and a Fisher's exact test were applied. Results: Twenty-eight subjects completed the protocol.The healing was reached by 7/9, 8/10 and 6/9 participants of the LLLT, HVPC and CG respectively in the 16th week. There were no statistically significant differences between the groups in the healing proportion, NCS, sensory testing or quality of life (p>0,05. Conclusions: The results of this study did not demonstrated additional effects of LLL or HVPC to the standard wound care (SWC on healing of diabetic ulcers.

  8. Evaluation of Low-Level Laser Therapy on Orthodontic Tooth Movement: A Randomized Control Study

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    Guneet Guram

    2018-01-01

    Full Text Available Background: Fixed orthodontic treatment is time-consuming procedure. Pain is usually associated with orthodontic treatment. The aim of the present study was to evaluate the role of low-level laser therapy (LLLT on orthodontic tooth movement (OTM duration and pain perception. Materials and Methods: This randomized double-blind splint-mouth controlled clinical study includes 20 (8 males and 12 females orthodontic patients requiring bilateral canine retraction. Time taken for canine retraction with LLLT (Group A over control (Group B quadrant on the same patient was assessed along with pain experience using facial pain scale. The data were tabulated and statistically evaluated using SPSS 20 for windows (Microsoft, Chicago, IL, USA and t-test with P 0.05. There was statistically significant decrease in rate of canine retraction in Group A compared to Group B. There was statistically significant difference for maxillary and mandibular arches in Group A whereas it was not significant in Group B. Pain experience was statistically significant till 2nd day, and after 3rd day, it was not significant between the groups. Conclusion: LLLT can reduce the fixed OTM timing and pain experience.

  9. Low-level laser (light) therapy (LLLT) for treatment of hair loss.

    Science.gov (United States)

    Avci, Pinar; Gupta, Gaurav K; Clark, Jason; Wikonkal, Norbert; Hamblin, Michael R

    2014-02-01

    Alopecia is a common disorder affecting more than half of the population worldwide. Androgenetic alopecia, the most common type, affects 50% of males over the age of 40 and 75% of females over 65. Only two drugs have been approved so far (minoxidil and finasteride) and hair transplant is the other treatment alternative. This review surveys the evidence for low-level laser therapy (LLLT) applied to the scalp as a treatment for hair loss and discusses possible mechanisms of actions. Searches of PubMed and Google Scholar were carried out using keywords alopecia, hair loss, LLLT, photobiomodulation. Studies have shown that LLLT stimulated hair growth in mice subjected to chemotherapy-induced alopecia and also in alopecia areata. Controlled clinical trials demonstrated that LLLT stimulated hair growth in both men and women. Among various mechanisms, the main mechanism is hypothesized to be stimulation of epidermal stem cells in the hair follicle bulge and shifting the follicles into anagen phase. LLLT for hair growth in both men and women appears to be both safe and effective. The optimum wavelength, coherence and dosimetric parameters remain to be determined. © 2013 Wiley Periodicals, Inc.

  10. Researchin chronic low-level gamma -irradiation on laboratory populations of Lemna minor

    International Nuclear Information System (INIS)

    Rasskazova, M.M.; Berestina, A.V.

    2012-01-01

    Researching carried out on the laboratory population of Lemna minor showed that the chronically γ-irradiated plants significantly reduced specific rate of population growth, accelerating the process of withering away of the fronds. Chronic irradiation with dose of 5,0 mGy/h stimulates the growth of the roots, and irradiation with a capacity of 50 mGy/h significantly increases the percentage of damage fronds. Found out independent of dose effect on the criterion of the number of deaths of individuals in the range of absorbed dose between 0,01 - 1 Gy. (authors)

  11. Efficacy of low-level laser therapy on hair regrowth in dogs with noninflammatory alopecia: a pilot study.

    Science.gov (United States)

    Olivieri, Lara; Cavina, Damiano; Radicchi, Giada; Miragliotta, Vincenzo; Abramo, Francesca

    2015-02-01

    Canine noninflammatory alopecia (CNA) is a heterogeneous group of skin diseases with different underlying pathogenesis. The therapeutic approach is challenging, and new options for treatment are desirable. To test the clinical efficacy of low-level laser therapy (LLLT) on hair regrowth in CNA. Seven dogs of different ages, breeds and genders with a clinical and histopathological diagnosis of noninflammatory alopecia. Each dog was treated twice weekly for a maximum of 2 months with a therapeutic laser producing the following three different wavelengths emerging simultaneously from 21 foci: 13 × 16 mW, 470 nm; 4 × 50 mW, 685 nm; and 4 × 200 mW, 830 nm. The fluence given was 3 J/cm(2) , frequency 5 Hz, amplitude of the irradiated area was 25 cm(2) and application time was 1.34 min. A predetermined alopecic area was left untreated and served as a control area. From one dog, post-treatment biopsies of treated and untreated sites were obtained for histological evaluation of hair density and the percentage of haired and nonhaired follicles. At the end of the study, coat regrowth was greatly improved in six of seven animals and improved in one of seven. By morphometry, the area occupied by hair follicles was 18% in the treated sample and 11% in the untreated one (11%); haired follicles were (per area) 93% in the treated sample and only 9% in the control sample. Our clinical and histological data document promising effects of LLLT on hair regrowth in CNA. Further studies investigating the biological mechanism underlying the effect of LLLT on hair follicle cycling are warranted. © 2014 ESVD and ACVD.

  12. Timing and low-level rf system for an x-ray laser

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    Yuji Otake

    2016-02-01

    Full Text Available An x-ray free-electron laser (XFEL, SACLA, designed to open up new science, was constructed for generating coherent x rays with a peak power of more than 10 GW and a very short pulse of below 30 fs. This feature demands a very highly short-term temporal stability of less than 50 fs to the acceleration rf field of SACLA. For this reason, we developed a timing and low-level rf (LLRF system for SACLA based on that of the SPring8 compact SASE source (SCSS test accelerator for verifying the feasibility of an XFEL. The performance of the system using the in-phase and quadrature rf manipulation method was improved from SCSS’s system. Since the facility length of SACLA is 700 m, which is 10 times longer than that of the SCSS test accelerator, a phase-stabilized optical-fiber system designed to transmit time standard rf signals with low loss was also developed and deployed. This optical-fiber system equips fiber optical-length feedback control in order to mitigate environmental effects, such as temperature and humidity changes. On the other hand, the demanded maximum rf temporal stability is less than 50 fs, which is almost 10 times smaller than that of the SCSS test accelerator. Hence, reducing electric noise and increasing the temperature stability around timing and LLRF instruments were necessary and realized with a very low-noise power supply and a hemathermal 19-inch enclosure. The short-term temporal performance of the timing LLRF system finally attained a temporal stability of less than 13.6 fs in rms measured by a beam arrival-time measurement. This stability greatly helps to achieve the stable x-ray lasing of SACLA for routine operation during user experiments.

  13. Low-level laser therapy improves the VO2 kinetics in competitive cyclists.

    Science.gov (United States)

    Lanferdini, Fábio J; Krüger, Renata L; Baroni, Bruno M; Lazzari, Caetano; Figueiredo, Pedro; Reischak-Oliveira, Alvaro; Vaz, Marco A

    2018-04-01

    Some evidence supports that low-level laser therapy (LLLT) reduces neuromuscular fatigue, so incrementing sports performance. A previous randomized controlled trial of our group showed increased exercise tolerance in male competitive cyclists treated with three different LLLT doses (3, 6, and 9 J/diode; or 135, 270, and 405 J/thigh) before time-to-exhaustion cycling tests. Now, the present study was designed to evaluate the effects of these LLLT doses on the VO 2 kinetics of athletes during cycling tests. Twenty male competitive cyclists (29 years) participated in a crossover, randomized, double-blind, and placebo-controlled trial. On the first day, the participants performed an incremental cycling test to exhaustion to determine maximal oxygen uptake (VO 2MAX ) and maximal power output (PO MAX ), as well as a familiarization with the time-to-exhaustion test. In the following days (2 to 5), all participants performed time-to-exhaustion tests at PO MAX . Before the exhaustion test, different doses of LLLT (3, 6, and 9 J/diode; or 135, 270, and 405 J/thigh, respectively) or placebo were applied bilaterally to the quadriceps muscle. All exhaustion tests were monitored online by an open-circuit spirometry system in order to analyze the VO 2 amplitude, VO 2 delay time, time constant (tau), and O 2 deficit. Tau and O 2 deficit were decreased with LLLT applications compared to the placebo condition (p  0.05) were found between the experimental conditions for VO 2 amplitude and VO 2 delay time. In conclusion, LLLT decreases tau and O 2 deficit during time-to-exhaustion tests in competitive cyclists, and these changes in VO 2 kinetics response can be one of the possible mechanisms to explain the ergogenic effect induced by LLLT.

  14. Low Level Laser Therapy Reduces the Development of Lung Inflammation Induced by Formaldehyde Exposure.

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    Cristiane Miranda da Silva

    Full Text Available Lung diseases constitute an important public health problem and its growing level of concern has led to efforts for the development of new therapies, particularly for the control of lung inflammation. Low Level Laser Therapy (LLLT has been highlighted as a non-invasive therapy with few side effects, but its mechanisms need to be better understood and explored. Considering that pollution causes several harmful effects on human health, including lung inflammation, in this study, we have used formaldehyde (FA, an environmental and occupational pollutant, for the induction of neutrophilic lung inflammation. Our objective was to investigate the local and systemic effects of LLLT after FA exposure. Male Wistar rats were exposed to FA (1% or vehicle (distillated water during 3 consecutive days and treated or not with LLLT (1 and 5 hours after each FA exposure. Non-manipulated rats were used as control. 24 h after the last FA exposure, we analyzed the local and systemic effects of LLLT. The treatment with LLLT reduced the development of neutrophilic lung inflammation induced by FA, as observed by the reduced number of leukocytes, mast cells degranulated, and a decreased myeloperoxidase activity in the lung. Moreover, LLLT also reduced the microvascular lung permeability in the parenchyma and the intrapulmonary bronchi. Alterations on the profile of inflammatory cytokines were evidenced by the reduced levels of IL-6 and TNF-α and the elevated levels of IL-10 in the lung. Together, our results showed that LLLT abolishes FA-induced neutrophilic lung inflammation by a reduction of the inflammatory cytokines and mast cell degranulation. This study may provide important information about the mechanisms of LLLT in lung inflammation induced by a pollutant.

  15. Effect of low level laser therapy on chronic compression of the dorsal root ganglion.

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    Yi-Jen Chen

    Full Text Available Dorsal root ganglia (DRG are vulnerable to physical injury of the intervertebral foramen, and chronic compression of the DRG (CCD an result in nerve root damage with persistent morbidity. The purpose of this study was to evaluate the effects of low level laser therapy (LLLT on the DRG in a CCD model and to determine the mechanisms underlying these effects. CCD rats had L-shaped stainless-steel rods inserted into the fourth and fifth lumbar intervertebral foramen, and the rats were then subjected to 0 or 8 J/cm2 LLLT for 8 consecutive days following CCD surgery. Pain and heat stimuli were applied to test for hyperalgesia following CCD. The levels of TNF-α, IL-1β and growth-associated protein-43 (GAP-43 messenger RNA (mRNA expression were measured via real-time PCR, and protein expression levels were analyzed through immunohistochemical analyses. Our data indicate that LLLT significantly decreased the tolerable sensitivity to pain and heat stimuli in the CCD groups. The expression levels of the pro-inflammatory cytokines TNF-α and IL-1β were increased following CCD, and we found that these increases could be reduced by the application of LLLT. Furthermore, the expression of GAP-43 was enhanced by LLLT. In conclusion, LLLT was able to enhance neural regeneration in rats following CCD and improve rat ambulatory behavior. The therapeutic effects of LLLT on the DRG during CCD may be exerted through suppression of the inflammatory response and induction of neuronal repair genes. These results suggest potential clinical applications for LLLT in the treatment of compression-induced neuronal disorders.

  16. Pre-1989 epidemiological surveys of low-level dose pre-conception irradiation

    International Nuclear Information System (INIS)

    Rose, K.S.B.

    1990-01-01

    Information from 59 pre-1989 epidemiological surveys concerning pre-conception irradiation at doses less than 0.1 Gy has been collated to determine whether any consistent patterns of health effects emerge. The surveys are considered in three groups: childhood malignancies, Down's syndrome and indicators of reproductive damage. Although a pattern is observed for Down's syndrome, no reliable associations are apparent for childhood malignancies (where all surveys pre-date the Gardner survey at Sellafield) or indications of reproductive damage. The twelve surveys of Down's syndrome in relation to maternal pre-conception irradiation received for medical reasons show a pattern consistent with a doubling dose of about 20 mGy. This doubling dose value is, however, not based on individual measurements of ovarian dose and is inconsistent with results from high-level dose surveys. There is no association between paternal irradiation and Down's syndrome. (author)

  17. Low-level laser therapy: An experimental design for wound management: A case-controlled study in rabbit model

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    Hossein Hodjati

    2014-01-01

    Full Text Available Background: There is a wide array of articles in medical literature for and against the laser effect on wound healing but without discrete effect determination or conclusion. This experimental study aims to evaluate the efficacy of low-level laser therapy on wound healing. Materials and Methods: Thirty-four rabbits were randomly enrolled in two groups after creating a full thickness of 3 × 3 cm wound. The intervention group received low density laser exposure (4 J/cm 2 on days 0, 3 and 6 with diode helium-neon low-intensity laser device (wl = 808 nm and in control group moist wound dressing applied. Finally, wound-healing process was evaluated by both gross and pathological assessment. Results: Fibrin formation was the same in the two groups (P = 0.4 but epithelialisation was much more in laser group (P = 0.02. Wound inflammation of the laser group was smaller than that of the control groups but statistical significance was not shown (P = 0.09. Although more smooth muscle actin was found in the wounds of the laser group but it was not statistically significant (P = 0.3. Wound diameter showed significant decrease in wound area in laser group (P = 0.003. Conclusion: According to our study, it seems that low-level laser therapy accelerates wound healing at least in some phases of healing process. So, we can conclude that our study also shows some hopes for low level laser therapy effect on wound healing at least in animal model.

  18. Comparison of the effects of 665 nm low level diode Laser Hat versus and a combination of 665 nm and 808nm low level diode Laser Scanner of hair growth in androgenic alopecia.

    Science.gov (United States)

    Barikbin, Behrooz; Khodamrdi, Zeinab; Kholoosi, Leila; Akhgri, Mohammad Reza; Haj Abbasi, Majid; Hajabbasi, Mojgan; Razzaghi, Zahra; Akbarpour, Samaneh

    2017-05-17

    This study aimed to evaluate the effectiveness of a combined set of low level diode laser scanner (665 nm and 808nm) on hair growth, and assessment of safety and effectiveness of a new laser scanner on hair growth treatment procedure in androgenic alopecia. 90 patients (18 to 70 years) with androgenic alopecia were randomized into three groups. The first group (n=30) received 655 nm red light using laser hat, the second group (n=30) received 655 nm red laser plus 808 nm infrared laser using a laser scanner of hair growth device (with the patent number: 77733) and the third group (n=30) received no laser as the control group. Patients in laser scanner group had better results and showed a higher increase in terminal hair density compared with laser hat group (mean of 9.61 versus 9.16 per cm 2 ). We found significant decrease in terminal hair density from baseline in control group (mean -1.8 per cm 2 , plaser scanner of the hair growth group compared with laser hat and the control group. The study showed that treatment with new laser devise had a promising result without any observable adverse effects.

  19. Evaluation of Oral Mucositis Occurrence in Oncologic Patients under Antineoplastic Therapy Submitted to the Low-Level Laser Coadjuvant Therapy.

    Science.gov (United States)

    Leite Cavalcanti, Alessandro; José de Macêdo, Dário; Suely Barros Dantas, Fernanda; Dos Santos Menezes, Karla; Filipe Bezerra Silva, Diego; Alves de Melo Junior, William; Fabia Cabral Cavalcanti, Alidianne

    2018-04-24

    Low-level laser therapy has been widely used in treating many conditions, including oral mucositis. The purpose of this study was to evaluate the occurrence of oral mucositis in patients undergoing antineoplastic therapy submitted to preventive and therapeutic treatment with low-level laser therapy. This cross-sectional study was carried out with 51 children and adolescents of both sexes with malignant neoplasias who developed oral mucositis and underwent low-level laser therapy. Data were collected on sex, age, type and degree of neoplasia, region affected, and remission time. 64.7% of the patients were male and were between 3 and 6 years of age (39.2%). Acute lymphoid leukemia was the most frequent neoplasm (37.3%). Regarding the maximum oral mucositis, grade 2 (41.2%) was predominant, with jugal mucosa (29.9%) and tongue (17.7%) being the most affected regions. The majority of cases presented lesion remission time between 4 and 7 days (44.0%). Most patients were young, male, and diagnosed with acute lymphoid leukemia. Predominance of grade 2 oral mucositis was observed, with jugal mucosa and tongue being the most affected regions, with the majority of cases presenting lesion remission time between 4 and 7 days. Low-level laser therapy has been shown to be an essential therapy in the prevention and treatment of these lesions, since it is a non-invasive and low-cost method.

  20. Evaluation of Oral Mucositis Occurrence in Oncologic Patients under Antineoplastic Therapy Submitted to the Low-Level Laser Coadjuvant Therapy

    Directory of Open Access Journals (Sweden)

    Alessandro Leite Cavalcanti

    2018-04-01

    Full Text Available Low-level laser therapy has been widely used in treating many conditions, including oral mucositis. The purpose of this study was to evaluate the occurrence of oral mucositis in patients undergoing antineoplastic therapy submitted to preventive and therapeutic treatment with low-level laser therapy. This cross-sectional study was carried out with 51 children and adolescents of both sexes with malignant neoplasias who developed oral mucositis and underwent low-level laser therapy. Data were collected on sex, age, type and degree of neoplasia, region affected, and remission time. 64.7% of the patients were male and were between 3 and 6 years of age (39.2%. Acute lymphoid leukemia was the most frequent neoplasm (37.3%. Regarding the maximum oral mucositis, grade 2 (41.2% was predominant, with jugal mucosa (29.9% and tongue (17.7% being the most affected regions. The majority of cases presented lesion remission time between 4 and 7 days (44.0%. Most patients were young, male, and diagnosed with acute lymphoid leukemia. Predominance of grade 2 oral mucositis was observed, with jugal mucosa and tongue being the most affected regions, with the majority of cases presenting lesion remission time between 4 and 7 days. Low-level laser therapy has been shown to be an essential therapy in the prevention and treatment of these lesions, since it is a non-invasive and low-cost method.

  1. Biostimulation effect of low-level laser on healing process after third molar surgery, based on biochemical markers in saliva

    Science.gov (United States)

    Kroulikova, Veronika; Dostálová, Tatjana; Podzimek, Stepan

    2015-02-01

    Third molar extractions in general anesthesia have become a standard procedure in dentistry. There is an effort to shorten healing time and decrease the number of complications as well as increase comfort after the treatment. Low-level lasers are known for their analgesic, anti-inflammatory, and stimulatory effect. The aim of the study is to evaluate the effect of low-level laser after surgery in general anesthesia reducing the patient's discomfort, i.e. mainly pain, and also, to monitor the biostimulation process. Our study included 79 patients treated at the Department of Maxilofacial Surgery, diagnosed with third molar retention. Diode low-level laser radiation (wavelength 830 nm, output power 270 mW, probe aperture of 6.4 mm2) with dose ~ 3 mJ was applied. The control group was treated by using placebo - red light. The exposure time was 11 seconds immediately after the suture; the treatment was repeated every day for the following 3 days. To evaluate the effect of laser biostimulation, the objective markers for immunological determination of healing - sIgA and lysozyme in non-stimulated saliva of patients - were used. The sIgA decreases after laser application from 546.91 mg/l to 304. 91mg/l and in the control group from 602.25mg/l to 425.62 mg/l. The results were statistically significant. The level of lysozyme decreases from 54.27 mg/l to 2.45mg/l after laser biostimulation, from 304.371mg/l to 11.08mg/l after placebo effect. The study has confirmed a low-level laser healing effect not directly related to pain.

  2. Successful Treatment of Resistant Discoid Lupus Erythematous (DLE With Low-Level Laser Therapy (LLLT: A Case Report

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    Nooshafarin Kazemikhoo

    2015-12-01

    Full Text Available Introduction Lupus is a chronic autoimmune illness characterized by production of autoantibodies against nuclear antigens. Lupus may also only appear as a skin disease. Discoid lupus erythematous (DLE, the most common form of chronic cutaneous lupus erythematous is characterized by patches of persistent erythema, adherent scaling, follicular plugging and, in the later stages scaring and atrophy. Case Presentation The case was a 33-year-old female with two years history of DLE, who referred to the laser clinic of Milad hospital with acute flare of skin lesions since seven months ego. She had four lesions (three with local alopecia, scaling and itching and one with atrophy. Serological studies for antinuclear antibodies and anti Ro/SS-A antibody were negative. After five sessions of treatment with infrared (830 nm; 200 mw and red light (630 nm; 20 mw diode laser in addition to intravenous red light laser (655 nm; 2 mw for 20 minutes and laser acupuncture with infrared diode laser (1 J/cm2 for six acupuncture points every other day, the beneficial effects started to appear, and after nine sessions, local itching of the lesions had stopped. Through a total of 27 sessions of treatment, the lesions improved completely with highly satisfactory results; and drug-therapy held to be continued. No disease flare up was seen after the one-year follow up. Conclusions To the best of our knowledge, this is the first case report on low-level laser therapy (LLLT treatment of DLE. Low-level laser therapy may be effective in treating inflammatory lesions such as cutaneous lesions of discoid lupus erythematous. More studies with higher sample size are needed to clarify the role of low level lasers in treating such lesions.

  3. 76 FR 20840 - Medical Devices; General and Plastic Surgery Devices; Classification of the Low Level Laser...

    Science.gov (United States)

    2011-04-14

    ... looking directly at the laser beam and the wearing of appropriate laser safety eyewear by both the user...). The special control for this device is the FDA guidance document entitled ``Guidance for Industry and...

  4. Caffeine enhanced measurement of mutagenesis by low levels of [gamma]-irradiation in human lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Puck, T.P.; Johnson, R.; Waldren, C.A. (Eleanor Roosevelt Institute for Cancer Research, Denver, CO (United States)); Morse, H. (Univ. of Colorado Cancer Center, Denver, CO (United States))

    1993-09-01

    The well-known action of caffeine in synergizing mutagenesis (including chromosome aberrations) of agents like ionizing radiation by inhibition of cellular repair processes has been incorporated into a rapid procedure for detection of mutagenicity with high sensitivity. Effects of 5-10 rads of [gamma]-irradiation, which approximate the human lifetime dose accumulation from background radiation, can be detected in a two-day procedure using an immortalized human WBC culture. Chromosomally visible lesions are scored on cells incubated for 2 h after irradiation in the presence and absence of 1.0 mg/ml of caffeine. An eightfold amplification of scorable lesions is achieved over the action of radiation alone. This approach provides a closer approximation to absolute mutagenicity unmitigated by repair processes, which can vary in different situations. It is proposed that mutagenesis testing of this kind, using caffiene or other repair-inhibitory agents, be employed to identify mutagens in their effective concentrations to which human populations may be exposed; to detect agents such as caffeine that may synergize mutagenic actions and pose epidemiologic threats; and to discover effective anti-mutagens. Information derived from the use of such procedures may help prevent cancer and newly acquired genetic disease.

  5. Laser irradiation reduces HIV-1 infection in TZM-bl cells

    CSIR Research Space (South Africa)

    Lugongolo, Masixole Y

    2016-10-01

    Full Text Available HIV-1 epidemic remains a major health challenge. This study explores the effects of low level laser therapy on HIV-1 infected cells. Infection is reduced by irradiation and the mechanism needs to be investigated further....

  6. Low-level laser therapy to the mouse femur enhances the fungicidal response of neutrophils against Paracoccidioides brasiliensis.

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    Eva Burger

    2015-02-01

    Full Text Available Neutrophils (PMN play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM, which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb. PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan, and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection.

  7. Aferição dos equipamentos de laser de baixa intensidade Calibration of low-level laser therapy equipment

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    Thiago Y. Fukuda

    2010-08-01

    Full Text Available CONTEXTUALIZAÇÃO: A laserterapia de baixa intensidade (LBI vem sendo cada vez mais utilizada, porém ainda não há consenso na literatura quanto ao tempo em que os equipamentos devem ser submetidos à aferição ou calibragem. OBJETIVO: Analisar a potência média real (PmR dos equipamentos de LBI na região da Grande São Paulo. MÉTODOS: Para análise dos equipamentos, utilizou-se um potenciômetro (Lasercheck, próprio para aferição de equipamentos contínuos, o qual foi programado com dados referentes ao comprimento de onda do laser a ser avaliado, obtendo-se assim a PmR emitida. Os equipamentos foram analisados de duas formas: uma, com o LBI desaquecido, e outra, após 10 minutos de uso (aquecido, sendo que três análises foram feitas para cada condição. A caneta emissora foi acoplada ao potenciômetro, o qual fornecia a PmR emitida pelo LBI. Todos os dados e informações referentes à aplicação do laser foram coletados por um questionário respondido pelos responsáveis. RESULTADOS: Os 60 equipamentos avaliados mostraram déficit na PmR com os equipamentos desaquecidos e aquecidos. A análise estatística (ANOVA mostrou diminuição significativa (PBACKGROUND: Despite the increase in the use of low-level laser therapy (LLLT, there is still a lack of consensus in the literature regarding how often the equipment must be calibrated. OBJECTIVE: To evaluate the real average power of LLLT devices in the Greater São Paulo area. METHODS: For the evaluation, a LaserCheck power meter designed to calibrate continuous equipment was used. The power meter was programmed with data related to the laser's wavelength to gauge the real average power being emitted. The LLLT devices were evaluated in two ways: first with the device cooled down and then with the device warmed up for 10 minutes. For each condition, three tests were performed. The laser probe was aligned with the power meter, which provided the real average power being emitted by the

  8. Peri-implant osseointegration after low-level laser therapy: micro-computed tomography and resonance frequency analysis in an animal model.

    Science.gov (United States)

    Mayer, Luciano; Gomes, Fernando Vacilotto; de Oliveira, Marília Gerhardt; de Moraes, João Feliz Duarte; Carlsson, Lennart

    2016-12-01

    The purpose of the present study is to evaluate the effects of low-level laser therapy on the osseointegration process by comparing resonance frequency analysis measurements performed at implant placement and after 30 days and micro-computed tomography images in irradiated vs nonirradiated rabbits. Fourteen male New Zealand rabbits were randomly divided into two groups of seven animals each, one control group (nonirradiated animals) and one experimental group that received low-level laser therapy (Thera Lase®, aluminum-gallium-arsenide laser diode, 10 J per spot, two spots per session, seven sessions, 830 nm, 50 mW, CW, Ø 0.0028 cm 2 ). The mandibular left incisor was surgically extracted in all animals, and one osseointegrated implant was placed immediately afterward (3.25ø × 11.5 mm; NanoTite, BIOMET 3i). Resonance frequency analysis was performed with the Osstell® device at implant placement and at 30 days (immediately before euthanasia). Micro-computed tomography analyses were then conducted using a high-resolution scanner (SkyScan 1172 X-ray Micro-CT) to evaluate the amount of newly formed bone around the implants. Irradiated animals showed significantly higher implant stability quotients at 30 days (64.286 ± 1.596; 95 % confidence interval (CI) 60.808-67.764) than controls (56.357 ± 1.596; 95 %CI 52.879-59.835) (P = .000). The percentage of newly formed bone around the implants was also significantly higher in irradiated animals (75.523 ± 8.510; 95 %CI 61.893-89.155) than in controls (55.012 ± 19.840; 95 %CI 41.380-68.643) (P = .027). Laser therapy, based on the irradiation protocol used in this study, was able to provide greater implant stability and increase the volume of peri-implant newly formed bone, indicating that laser irradiation effected an improvement in the osseointegration process.

  9. Basal body and striated rootlet changes in primate macular retinal pigmented epithelium after low level diffuse argon laser radiation. Final report 1981-1982

    Energy Technology Data Exchange (ETDEWEB)

    Schuschereba, S.T.; Zwick, H.; Stuck, B.E.; Beatrice, E.S.

    1982-09-01

    Basal bodies or centrioles (BB - microtubule organizing centers) and striated rootlets (SR - bundles of 60 A action-like filaments) have a close association in primate retinal pigmented epithelial (RPE) cells. The frequency of occurrence of these structures was evaluated in the macular RPE after repeated exposure to low level diffuse argon laser radiation (DALR). The awake chaired animal's head was restrained and positioned near the center of the 0.75 m hemisphere which was diffusely irradiated with 514.5 nm laser radiation. The right eye of each subject was occluded during the two-hour exposure session. The first subject received 24 cumulative hours of exposure, the second, 40 hours and the third, 42 hours.

  10. INHIBITION OF AFLATOXIN PRODUTION BY ASPERGILLUS FLAVUS USING LOW LEVEL Y - IRRADIATION

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    F

    1981-05-01

    Full Text Available Effects o f s e l ected l ow l evel doses of y - Rad iation (100-400 K rad on t he abi l ity o f toxin strain o f Asperg i l l us flavus t o survive and pr oduce a f latox in in c ul t ure med ium and p is tachio nuts hav e been s tudied . A reduction of 60 per c e nt in growth and spore production by Asperg i l l us flavus in c u l ture me di um was observed after treatment wi th 100 K rad of y - Radiation ."nIn spore inoculated pistachio nuts , 100 K rad o f y Radi a tion reduced the a f la toxin B l and G l nroduction by 75% aft er e i ght week s s t orage per iod . The afla toxin prod~ ction ability by Aspergillus f lavus on pistachio nuts was affectively eliminated by t he treatment o f spore inoculated pist achio nuts wi th 200 K rad of y-Radiation , although very l itt le growth coul d be detected after eight weeks ' storage of 40 0 K rad y-irradiated pistachio nuts.  

  11. The effect of low-level laser therapy on trismus and facial swelling following surgical extraction of a lower third molar.

    Science.gov (United States)

    Aras, Mutan Hamdi; Güngörmüş, Metin

    2009-02-01

    The purpose of this study was to evaluate the effect of low-level laser therapy (LLLT) on postoperative trismus and edema after the removal of mandibular third molars. Thirty-two patients who were to undergo surgical removal of lower third molars were studied. Patients were randomly allocated to two groups, LLLT and placebo. Patients in the LLLT group received 12 J (4 J/cm(2)) low-level laser irradiation to the operative side intraorally 1 cm from the target tissue, and to the masseter muscle extraorally immediately after surgery. In the placebo group the handpiece was inserted into the operative side intraorally and was applied to the masseter muscle extraorally each for 1 min, but laser power was not activated. Inter-incisal opening and facial swelling were evaluated on postoperative days 2 and 7. Student's t-test used to analyze the data. It was determined that the trismus and the swelling in LLLT group were significantly less than in the placebo group on postoperative days 2 and 7. Within the limitations of this study it can be concluded that LLLT can be beneficial for the reduction of postoperative trismus and swelling after third molar surgery.

  12. The Relevance of Chromosome Aberration Yields for Biological Dosimetry After Low-Level Occupational Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bauchinger, M.; Schmid, E.; Hug, O. [Gesellschaft fuer Strahlenforschung, Institut fuer Biologie, Neuherberg, Federal Republic of Germany (Germany); Strahlenbiologisches Institut der Universitaet Muenchen, Federal Republic of Germany (Germany)

    1971-06-15

    The usefulness of chromosome analysis for biological dosimetry has been tested in two groups of persons occupationally exposed to radiation: (I) in nurses employed in gynaecological radiology, exposed especially when handling radium inserts; and (II) in nuclear industry workers, all of which were exposed to external gamma irradiation and some of them also to internal radiation after incorporation of various radionuclides. The total dose registered with personal dosimeters ranged in Group 1 from 0.1 to 91.1 rem accumulated over working periods of 0.1 to 13 years, and in Group II from 1.0 to 18.2 rem accumulated over 1 to 9 years. Compared with unexposed controls, both groups exhibit a significant increase of cells with chromosome aberrations as well as larger numbers of breaks per cell. Dicentrics and rings could be observed in some cells, providing good evidence for previous radiation exposure, since these types of aberrations are extremely rare events in unexposed individuals. No correlation between the aberration yields and the film badge values could be demonstrated in Group II. Also, in Group I the fluctuations from individual to individual are rather high. Nevertheless, a positive correlation to the ''dose'' was obtained. Even a sub-group of the nurses that had only been exposed to 20 rem showed significantly more aberrations than control persons. From the results obtained, type and frequency of chromosome aberrations may be considered an indicator of radiation exposure even at the low doses. The reasons for lack of correspondence of chromosome aberration yields and the results of personal monitoring procedures are discussed in detail. (author)

  13. Low-level lasers alter mRNA levels from traditional reference genes used in breast cancer cells

    Science.gov (United States)

    Teixeira, A. F.; Canuto, K. S.; Rodrigues, J. A.; Fonseca, A. S.; Mencalha, A. L.

    2017-07-01

    Cancer is among the leading causes of mortality worldwide, increasing the importance of treatment development. Low-level lasers are used in several diseases, but some concerns remains on cancers. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) is a technique used to understand cellular behavior through quantification of mRNA levels. Output data from target genes are commonly relative to a reference that cannot vary according to treatment. This study evaluated reference genes levels from MDA-MB-231 cells exposed to red or infrared lasers at different fluences. Cultures were exposed to red and infrared lasers, incubated (4 h, 37 °C), total RNA was extracted and cDNA synthesis was performed to evaluate mRNA levels from ACTB, GUSB and TRFC genes by RT-qPCR. Specific amplification was verified by melting curves and agarose gel electrophoresis. RefFinder enabled data analysis by geNorm, NormFinder and BestKeeper. Specific amplifications were obtained and, although mRNA levels from ACTB, GUSB or TRFC genes presented no significant variation through traditional statistical analysis, Excel-based tools revealed that the use of these reference genes are dependent of laser characteristics. Our data showed that exposure to low-level red and infrared lasers at different fluences alter the mRNA levels from ACTB, GUSB and TRFC in MDA-MB-231 cells.

  14. Can combined use of low-level lasers and hyaluronic acid injections prolong the longevity of degenerative knee joints?

    Science.gov (United States)

    Ip, David; Fu, Nga Yue

    2015-01-01

    This study evaluated whether half-yearly hyaluronic acid injection together with low-level laser therapy in addition to standard conventional physical therapy can successfully postpone the need for joint replacement surgery in elderly patients with bilateral symptomatic tricompartmental knee arthritis. In this prospective, double-blind, placebo-controlled study, 70 consecutive unselected elderly patients with bilateral tricompartmental knee arthritis were assigned at random to either one of two conservative treatment protocols to either one of the painful knees. Protocol A consisted of conventional physical therapy plus a sham light source plus saline injection, and protocol B consisted of protocol A with addition of half-yearly hyaluronic acid injection as well as low-level laser treatment instead of using saline and a sham light source. Treatment failure was defined as breakthrough pain necessitating joint replacement. Among the 140 painful knees treated with either protocol A or protocol B, only one of the 70 painful knees treated by protocol B required joint replacement, whereas 15 of the 70 painful knees treated by protocol A needed joint replacement surgery (Phyaluronic acid injections together with low-level laser therapy should be incorporated into the standard conservative treatment protocol for symptomatic knee arthritis, because it may prolong the longevity of the knee joint without the need for joint replacement.

  15. Effects of power densities, continuous and pulse frequencies, and number of sessions of low-level laser therapy on intact rat brain.

    Science.gov (United States)

    Ilic, Sanja; Leichliter, Sandra; Streeter, Jackson; Oron, Amir; DeTaboada, Luis; Oron, Uri

    2006-08-01

    The aim of the present study was to investigate the possible short- and long-term adverse neurological effects of low-level laser therapy (LLLT) given at different power densities, frequencies, and modalities on the intact rat brain. LLLT has been shown to modulate biological processes depending on power density, wavelength, and frequency. To date, few well-controlled safety studies on LLLT are available. One hundred and eighteen rats were used in the study. Diode laser (808 nm, wavelength) was used to deliver power densities of 7.5, 75, and 750 mW/cm2 transcranially to the brain cortex of mature rats, in either continuous wave (CW) or pulse (Pu) modes. Multiple doses of 7.5 mW/cm2 were also applied. Standard neurological examination of the rats was performed during the follow-up periods after laser irradiation. Histology was performed at light and electron microscopy levels. Both the scores from standard neurological tests and the histopathological examination indicated that there was no long-term difference between laser-treated and control groups up to 70 days post-treatment. The only rats showing an adverse neurological effect were those in the 750 mW/cm2 (about 100-fold optimal dose), CW mode group. In Pu mode, there was much less heating, and no tissue damage was noted. Long-term safety tests lasting 30 and 70 days at optimal 10x and 100x doses, as well as at multiple doses at the same power densities, indicate that the tested laser energy doses are safe under this treatment regime. Neurological deficits and histopathological damage to 750 mW/cm2 CW laser irradiation are attributed to thermal damage and not due to tissue-photon interactions.

  16. Biomechanical properties: effects of low-level laser therapy and Biosilicate® on tibial bone defects in osteopenic rats.

    Science.gov (United States)

    Fangel, Renan; Bossini, Paulo S; Renno, Ana Cláudia; Granito, Renata N; Wang, Charles C; Nonaka, Keico O; Driusso, Patricia; Parizotto, Nivaldo A; Oishi, Jorge

    2014-12-30

    The aim of this study was to investigate the effects of laser therapy and Biosilicate® on the biomechanical properties of bone callus in osteopenic rats. Fifty female Wistar rats were equally divided into 5 groups (n=10/group): osteopenic rats with intact tibiae (SC); osteopenic rats with unfilled and untreated tibial bone defects (OC); osteopenic rats whose bone defects were treated with Biosilicate® (B); osteopenic rats whose bone defects were treated with 830-nm laser, at 120 J/cm2 (L120) and osteopenic rats whose bone defects were treated with Biosilicate® and 830-nm laser, at 120 J/cm2 (BL120). Ovariectomy (OVX) was used to induce osteopenia. A non-critical bone defect was created on the tibia of the osteopenic animals 8 weeks after OVX. In Biosilicate® groups, bone defects were completely filled with the biomaterial. For the laser therapy, an 830-nm laser, 120 J/cm2 was used. On day 14 postsurgery, rats were euthanized, and tibiae were removed for biomechanical analysis. Maximal load and energy absorption were higher in groups B and BL120, according to the indentation test. Animals submitted to low-level laser therapy (LLLT) did not show any significant biomechanical improvement, but the association between Biosilicate® and LLLT was shown to be efficient to enhance callus biomechanical properties. Conversely, no differences were found between study groups in the bending test. Biosilicate® alone or in association with low level laser therapy improves biomechanical properties of tibial bone callus in osteopenic rats.

  17. Low-level laser therapy in the prevention of radiotherapy-induced xerostomia and oral mucositis

    International Nuclear Information System (INIS)

    Lopes, Carlos de Oliveira; Mas, Josepa Rigau I.; Zangaro, Renato Amaro

    2006-01-01

    Objective: to verify if the use of InGaAIP laser with 685 nm wave length can reduce the xerostomy incidence, the oral mucositis severity and the pain related to mucositis in patients with head and neck cancer submitted to radiotherapy. Objective: sixty patients presenting head and neck carcinoma were submitted to radiotherapy with daily doses of 1.8 to 2.0 Gy and a final dose of 45 to 72 Gy. The salivary volume was evaluated in the first and fifteenth days, at the end of the treatment and after 15 and 30 days. The oral mucositis was evaluated on a weekly basis. Twenty-nine patients were submitted to radiotherapy without laser and 31 were submitted to radiotherapy and laser with daily doses of 2 joules/cm 2 in predetermined areas of the oral mucosa and the parotid and submandibular glands. Results: in the group submitted to radiotherapy and laser the incidence of mucositis (p < 0.001) and pain (p < 0.016) was significantly lower and the salivary volume (p < 0.001) was kept higher during and after the treatment. Conclusion: the group of patients submitted to radiotherapy and laser had lower incidence of xerostomy, oral mucositis and pain when compared to the group treated with radiotherapy without laser, producing statistically significant results. (author)

  18. Using laser irradiation for the surgical treatment of periodontal disease

    Science.gov (United States)

    Vieru, Rozana D.; Lefter, Agafita; Herman, Sonia

    2002-10-01

    In the marginal pr ogressive profound periodontities, we associated low level laser therapy (LLLT) to the classical surgical treatment with implant of biovitroceramics. From a total of 50 patients, 37 where irradiated with the laser. We used a diode laser, =830 nm, energy density up to 2 J cm2, in Nogier pulsed mode. The laser treatment is used in a complex of therapeutic procedures: odontal, local anti-inflammatory -- as well as in the cabinet and at home --, prosthetic, and for the morphologic and functional rebalancing. The immediate effects where: an evolution without bleeding and without post-surgical complications, as can appear at the patients who didn't benefit of laser irradiation (hematom, pain, functional alteration in the first post-surgical week). Operated tissue is recovering faster. The percentage of recurrences decreases and the success depends less on the biological potential and the immunity of each individual.

  19. Influence of postoperative low-level laser therapy on the osseointegration of self-tapping implants in the posterior maxilla: a 6-week split-mouth clinical study.

    Science.gov (United States)

    Mandić, Borka; Lazić, Zoran; Marković, Aleksa; Mandić, Bojan; Mandić, Miška; Djinić, Ana; Miličić, Biljana

    2015-03-01

    Low-level laser therapy (LLLT) has been proven to stimulate bone repair, affecting cellular proliferation, differentiation and adhesion, and has shown a potential to reduce the healing time following implant placement. The aim of this clinical study was to investigate the influence of postoperative LLLT osseointegration and early success of self-tapping implants placed into low-density bone. Following the split-mouth design, self-tapping implants n = 44) were inserted in the posterior maxilla of 12 patients. One jaw side randomly received LLLT (test group), while the other side was placebo (control group). For LLLT, a 637 nm gallium-aluminum-arsenide (GaAlAs) laser (Medicolaser 637, Technoline, Belgrade, Serbia) with an output power of 40 mW and continuous wave was used. Low-level laser treatment was performed immediately after the surgery and then repeated every day in the following 7 days. The total irradiation dose per treatment was 6.26 J/cm2 per implant. The study outcomes were: implant stability, alkaline-phosphatase (ALP) activity and early implant success rate. The follow-up took 6 weeks. Irradiated implants achieved a higher stability compared with controls during the entire follow-up and the difference reached significance in the 5th postoperative week (paired t-test, p = 0.030). The difference in ALP activity between the groups was insignificant in any observation point (paired t-test, p > 0.05). The early implant success rate was 100%, regardless of LLLT usage. LLLT applied daily during the first postoperative week expressed no significant influence on the osseointegration of self-tapping implants placed into low density bone of the posterior maxilla. Placement of self-tapping macro-designed implants into low density bone could be a predictable therapeutic procedure with a high early success rate regardless of LLLT usage.

  20. Influence of postoperative low-level laser therapy on the osseointegration of self-tapping implants in the posterior maxilla: A 6-week split-mouth clinical study

    Directory of Open Access Journals (Sweden)

    Mandić Borka

    2015-01-01

    Full Text Available Background/Aim. Low-level laser therapy (LLLT has been proven to stimulate bone repair, affecting cellular proliferation, differentiation and adhesion, and has shown a potential to reduce the healing time following implant placement. The aim of this clinical study was to investigate the influence of postoperative LLLT osseointegration and early success of self-tapping implants placed into low-density bone. Methods. Following the split-mouth design, self-tapping implants (n = 44 were inserted in the posterior maxilla of 12 patients. One jaw side randomly received LLLT (test group, while the other side was placebo (control group. For LLLT, a 637 nm gallium-aluminum-arsenide (GaAlAs laser (Medicolaser 637, Technoline, Belgrade, Serbia with an output power of 40 mW and continuous wave was used. Low-level laser treatment was performed immediately after the surgery and then repeated every day in the following 7 days. The total irradiation dose per treatment was 6.26 J/cm² per implant. The study outcomes were: implant stability, alkaline-phosphatase (ALP activity and early implant success rate. The follow-up took 6 weeks. Results. Irradiated implants achieved a higher stability compared with controls during the entire follow-up and the difference reached significance in the 5th postoperative week (paired t-test, p = 0.030. The difference in ALP activity between the groups was insignificant in any observation point (paired t-test, p > 0.05. The early implant success rate was 100%, regardless of LLLT usage. Conclusion. LLLT applied daily during the first postoperative week expressed no significant influence on the osseointegration of selftapping implants placed into low density bone of the posterior maxilla. Placement of self-tapping macro-designed implants into low density bone could be a predictable therapeutic procedure with a high early success rate regardless of LLLT usage.

  1. Comparative study of Low-level laser therapy and microcurrent on the healing of skin burns in rats

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    Rodrigo Pegado de Abreu Freitas

    2014-03-01

    This study investigated and compared the effects of low-level laser therapy (LLLT and microcurrent in the burn healing process in Wistar rats. We conducted a randomized controlled study with 30 rats divided into 3 groups (n = 10; control group (CG, laser group (LG and microcurrent group (MG. After thermal damage, 10 applications of 660 nm diode laser were performed in GL and 10 applications of 60 Hz microcurrent (160 μA in MG. The semi-quantitative histological analysis was done using scores (0–3, in sections stained by hematoxylin and eosin and Masson’s trichrome. The results indicated a significant improvement in the fibroblasts proliferation, collagen fibers deposition, neoangiogenesis, and cutaneous appendages regeneration in MG and LG. When microcurrent and LLLT were compared, no difference was detected, except the regeneration and formation of new cutaneous appendages, observed in MG. Despite the similar effects, GM showed faster tissue repair with the formation of skin appendages.

  2. Outcome of low level lasers versus ultrasonic therapy in de Quervain’s tenosynovitis

    Directory of Open Access Journals (Sweden)

    Renu Sharma

    2015-01-01

    Results: Significant improvement was seen within both groups in the following outcome measures assessed: Ritchie’s tenderness scale, grip strength and VAS. Finkelstein’s test was not significantly improved in either groups. Ultrasonographic measurement of tendon sheath diameters, the mediolateral (ML, and anteroposterior (AP diameters was not found to be significantly different in the US Th. group and the laser therapy group after treatment. On comparing both the groups, no statistically significant difference was found. However, looking at the mean values, the grip strength and VAS showed better improvement in the US Th. group as compared to the laser therapy group.

  3. Effectiveness of Low-Level Laser Therapy in Temporomandibular Joint Disorders: A Placebo-Controlled Study

    Czech Academy of Sciences Publication Activity Database

    Fikáčková, H.; Dostálová, T.; Navrátil, L.; Klaschka, Jan

    2007-01-01

    Roč. 25, č. 4 (2007), s. 297-303 ISSN 1549-5418 Grant - others:GA MZd(CZ) NR8112 Institutional research plan: CEZ:AV0Z10300504 Keywords : temporomandibular joint disorder * laser therapy Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 1.230, year: 2007

  4. The determination of low level trace elements in coals by laser ablation-inductively coupled plasma-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Booth, C.A.; Spears, D.A.; Krause, P.; Cox, A.G. [University of Sheffield, Sheffield (United Kingdom). Dept. of Earth Sciences

    1999-11-01

    The rapid determination of elements present in low level concentrations in bituminous coals is possible using laser abalation-inductively coupled plasma-mass spectrometry (l.a.-i.c.p.-m.s.). A wide range of trace elements can routinely be determined using this technique but it is for environmentally sensitive elements, such as As, Cd, Mo, Sb, Se and Hg, that it is of most use due to the low levels of detection. Calibration of the i.c.p.-m.s. was achieved using a series of uncertified coals and the method evaluated using the South African certified coals, Sarm 18, 19 and 20. A critical evaluation of the data obtained shows that for many of the elements studied the results obtained are both accurate and precise, even at very low concentrations, with the limits of detection for all of the elements being in the {mu}g/kg (parts per billion) range. 6 refs., 3 figs., 9 tabs.

  5. Low-level laser therapy induces an upregulation of collagen gene expression during the initial process of bone healing: a microarray analysis

    Science.gov (United States)

    Tim, Carla Roberta; Bossini, Paulo Sérgio; Kido, Hueliton Wilian; Malavazi, Iran; von Zeska Kress, Marcia Regina; Carazzolle, Marcelo Falsarella; Rennó, Ana Cláudia; Parizotto, Nivaldo Antonio

    2016-08-01

    This study investigates the histological modifications produced by low level laser therapy (LLLT) on the first day of bone repair, as well as evaluates the LLLT effects on collagen expression on the site of a fracture. Twenty Wistar rats were distributed into a control group (CG) and a laser group (LG). Laser irradiation of Ga-Al-As laser 830 nm, 30 mW, 94 s, 2.8 J was performed in five sessions. Animals were euthanized on day 5 postsurgery. Histopathological analysis showed that LLLT was able to increase deposition of granulation tissue and newly formed bone at the site of the injury. In addition, picrosirius analysis showed that collagen fiber organization in the LG was enhanced compared to CG. Microarray analysis demonstrated that LLLT produced an upregulation type I collagen (COL-I). Immunohistochemical analysis revealed that the subjects that were treated presented a higher immunoexpression of COL-I. Our findings indicated that LLLT improves bone healing by producing a significant increase in the expression of collagen genes.

  6. Use of low-level laser therapy in treatment of the androgenic alopecia, the first systematic review.

    Science.gov (United States)

    Najem, Ibrahim; Chen, Hongxiang

    2017-12-11

    Alopecia is a common disease affecting more than half of the world total number of people. Alopecia exists in different types, but one of the most common of these types is the Androgenic Alopecia which has affected approximately 51% of the total number of males ranging between the age bracket of 40 years and 75 years. This type of alopecia is more common in females who are above the age of 65 years and above. Despite this widespread effect, much has not been done regarding identifying the possible drugs for treating this disease. At present, there exist only two possible medications that have been scientifically approved to cure this disease, include finasteride and minoxidil. Also, another possible form of treatment has been the case of hair transplantation. Despite the new possible treatment options available for treatment of different types of hair loss, there is a need for the invention for more efficient management and treatment options that are less costly, environmentally friendly, and most importantly human consumption friendly. Due to the recent evaluation that low-level laser therapy stimulated hair growth. This systematic review and meta-analysis was to determine whether the use of low-level laser therapy is an effective therapy for treatment of the Androgenic alopecia and also to some degree we reviewed the level of the patient's satisfaction. Some earlier studies had shown that the use of low-level laser therapy stimulated the hair growth when mice were treated with chemotherapy which was induced by the alopecia and also the other type of alopecia called alopecia areata. The researchers hypothesized that the primary mechanism of treating Androgenic alopecia to be the stimulation of the epidermal stem cells which are in the hair follicle making them bulge and shift the follicles into the anagen phase.

  7. Low-level laser treatment accelerated hair regrowth in a rat model of chemotherapy-induced alopecia (CIA).

    Science.gov (United States)

    Wikramanayake, Tongyu Cao; Villasante, Alexandra C; Mauro, Lucia M; Nouri, Keyvan; Schachner, Lawrence A; Perez, Carmen I; Jimenez, Joaquin J

    2013-05-01

    Chemotherapy-induced alopecia (CIA) is one of the most distressing side effects of antineoplastic chemotherapy for which there is no effective interventional approach. A low-level laser (LLL) device, the HairMax LaserComb®, has been cleared by the FDA to treat androgenetic alopecia. Its effects may be extended to other settings; we have demonstrated that LaserComb treatment induced hair regrowth in a mouse model for alopecia areata. In the current study, we tested whether LLL treatment could promote hair regrowth in a rat model for CIA. Chemotherapy agents cyclophosphamide, etoposide, or a combination of cyclophosphamide and doxorubicin were administered in young rats to induce alopecia, with or without LLL treatment. As expected, 7-10 days later, all the rats developed full body alopecia. However, rats receiving laser treatment regrew hair 5 days earlier than rats receiving chemotherapy alone or sham laser treatment (with the laser turned off). The accelerated hair regrowth in laser-treated rats was confirmed by histology. In addition, LLL treatment did not provide local protection to subcutaneously injected Shay chloroleukemic cells. Taken together, our results demonstrated that LLL treatment significantly accelerated hair regrowth after CIA without compromising the efficacy of chemotherapy in our rat model. Our results suggest that LLL should be explored for the treatment of CIA in clinical trials because LLL devices for home use (such as the HairMax LaserComb®) provide a user-friendly and noninvasive approach that could be translated to increased patient compliance and improved efficacy.

  8. Medication-Related Osteonecrosis of Jaws: A Low-Level Laser Therapy and Antimicrobial Photodynamic Therapy Case Approach

    Directory of Open Access Journals (Sweden)

    Mariana Comparotto Minamisako

    2016-01-01

    Full Text Available Medication-related osteonecrosis of the jaws (MRONJ can be considered an inability of the alveolar bone to respond to an injury, which frequently leads to severe local and systemic complications. Once the problem is installed, dentist must use all therapeutic approaches recommended. This manuscript reports a successful management of MRONJ handled with antibiotics, conservative debridement, low-level laser therapy (LLLT, and photodynamic therapy (PDT up to 12 months. As healing of MRONJ may be very slow, combined therapeutic approaches are required. Besides the recommended conventional treatment protocol, LLLT and PDT are important tools to contribute to healing and improvement of patient’s quality of life.

  9. Implantable Self-Powered Low-Level Laser Cure System for Mouse Embryonic Osteoblasts' Proliferation and Differentiation.

    Science.gov (United States)

    Tang, Wei; Tian, Jingjing; Zheng, Qiang; Yan, Lin; Wang, Jiangxue; Li, Zhou; Wang, Zhong Lin

    2015-08-25

    Bone remodeling or orthodontic treatment is usually a long-term process. It is highly desirable to speed up the process for effective medical treatment. In this work, a self-powered low-level laser cure system for osteogenesis is developed using the power generated by the triboelectric nanogenerator. It is found that the system significantly accelerated the mouse embryonic osteoblasts' proliferation and differentiation, which is essential for bone and tooth healing. The system is further demonstrated to be driven by a living creature's motions, such as human walking or a mouse's breathing, suggesting its practical use as a portable or implantable clinical cure for bone remodeling or orthodontic treatment.

  10. Low-level laser therapy: Effects on human face aged skin and cell viability of HeLa cells exposed to UV radiation

    Directory of Open Access Journals (Sweden)

    Mezghani Sana

    2015-01-01

    Full Text Available Chronic and excessive exposure to UV radiation leads to photoaging and photocarcinogenesis. Adequate protection of the skin against the deleterious effects of UV irradiation is essential. Low-level laser therapy (LLLT is a light source in the red to near-infrared range that has been accepted in a variety of medical applications. In this study, we explored the effect of LLLT in human face aged skin and the cell viability of HeLa cells exposed to UV radiation. We found that LLLT significantly reduced visible wrinkles and the loss of firmness of facial skin in aging subjects. Additionally, treatment of cultured HeLa cells with LLLT prior to or post UVA or UVB exposure significantly protected cells from UV-mediated cell death. All results showed the beneficial effects of LLLT on relieving signs of skin aging and its prevention and protection of the cell viability against UV-induced damage.

  11. Effect of UV laser irradiation on tissue

    International Nuclear Information System (INIS)

    Nakayama, Takeyoshi; Kubo, Uichi

    1992-01-01

    Laser-tissue interactions have been investigated through Electron Probe Micro Analysis (EPMA), UV-visible optical absorption and Fourier Transform Infrared Spectroscopy (FTIR). Three excimer lasers, ArF, KrF and XeCl, were used to irradiate tissue; cow thighbone and gelatin thin film. Features of UV laser irradiation are described. (author)

  12. Amyotrophic Lateral Sclerosis (ALS) treated with Low Level LASER Therapy (LLLT): a case report

    Science.gov (United States)

    Longo, Leonardo; Postiglione, Marco; Gabellini, Massimiliano; Longo, Diego

    2009-06-01

    The topic concerns the effect of LLLT on ALS. The purpose is to find a new and effective approach to treat ALS by utilizing the beneficial biological effects on human tissues provided by LLLT and by testing the effectiveness of a specific treatment protocol. There are no reports in literature dealing with this topic. A 69 year old male with signs of lower motor neuron degeneration diagnosed in 2003 as ALS was given LLLT. Two different types of LASERs (wavelengths 810 and 890 nm) where used with specific parameters in March 2007. Three cycles of 20 daily sessions at 40 days interval were given. Gradual and significant improvements were noted after each cycle particularly appreciated by the patient especially in muscular mobility and respiratory functions. However signs of improvement 20 days after the third cycle showed a tendency to regression. Results obtained indicate that LLLT with the specific protocol used gives significant improvement of the ALS clinical picture but that its duration is not permanent. Further research on a large cohort is justified especially as regards LASER parameters and treatment cycles.

  13. Study on analgesic effect of low level laser and its mechanism%低强度激光镇痛效应及其机理探讨

    Institute of Scientific and Technical Information of China (English)

    陈静静; 杨华元; 马忆南; 赵宇平

    2011-01-01

    Low level laser irradiation has been widely used in clinical practice, which is reported by a large number of relevant articles. It has a good effect on both acute and chronic pain relief according to numerous research reports. Laser acupuncture as a combination product of traditional meridian theory and modem photobiology theory, which takes more advantages in medical research and application, compared with traditional acupuncture. As laser plays a variety of biological effects on body tissues, and the types of interaction are complex. Although clinical applications of laser acupuncture are quite a lot, not all experiments support its analgesic effect. As the clarification of the mechanism on laser analgesia is the key point to settle clinical disputes, thus this article focuses on the special organizational structure of acupoints and related animal experiments, and analyze reliable mechanisms of low level laser treatment for pain, which will provide a theoretical basis for practical application of laser acupuncture, and thus can better serve the clinical application.%通过对相关文献整理分析,发现低强度激光照射在临床已有广泛应用,其对缓解各种急慢性疼痛均有很好疗效,而激光针灸作为传统经络理论和现代光生物学理论相结合的产物,与传统针灸相比更具优点,决定了它在医学上的研究与应用更有广阔前景.但激光与机体相互作用类型复杂,能对生物组织发挥多种生物效应,且激光针灸在临床应用虽多,但并不是所有实验都支持其具有镇痛效应.由于阐明激光镇痛机制研究是解决临床争端的关键所在,所以本文就穴位的特殊组织结构以及目前所做相关动物实验研究入手,分析低强度激光镇痛的可能机理,为激光针灸的临床实际应用提供理论基础,以期更好服务于临床.

  14. O efeito do laser de baixa energia no crescimento bacteriano "in vitro" Low level laser effect in "in vitro" bacterial growth

    Directory of Open Access Journals (Sweden)

    Fernando Coutinho

    2007-08-01

    Full Text Available OBJETIVO: Avaliar, por meio de estudo bacteriológico in vitro, o efeito de dois tipos de laser de baixa energia (LBE sobre diferentes populações bacterianas habitualmente presentes em feridas pós-traumáticas. MÉTODOS: Foram colhidos swabs diretamente do sítio de infecção de pacientes internados com osteomielite pós-traumática crônica. As bactérias isoladas foram Acinetobacter baumanii complex, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonela sp, Serratia sp e Staphylococcus aureus. O material coletado foi semeado em meio ágar-sangue, através de alça estéril, utilizando-se 30 placas de Petri para cada germe. Foram utilizados dois aparelhos de LBE: Ibramed Laser Pulse #01189, com 15W/904nm por 200 segundos, e Phisiolux dual Bioset #9909001, com 20W/904nm por 230 segundos. Nos grupos I (n = 10 e II (n = 10, as bactérias sofreram irradiação pelo laser. O grupo III (n = 10 serviu de controle, não sendo irradiado. As bactérias dos grupos I e II foram irradiadas em câmara de fluxo laminar, previamente esterilizada por raio ultravioleta. O laser foi administrado de forma direta, central e perpendicularmente à superfície de cultivo das bactérias, com distância-padrão de 1cm, através de orifício confeccionado na tampa das placas. O crescimento bacteriano foi analisado após 12 e 24 horas da irradiação. Os resultados foram processados estatisticamente, utilizando-se o teste não-paramétrico de Kruskall-Wallis, com nível de significância p OBJECTIVE: To perform an in vitro bacteriologic study to evaluate the effect of two types of low level laser (LLL on different bacterial populations usually present in post-traumatic wounds. METHODS: Swabs were prepared directly at the infection site of patients hospitalized with chronic post-traumatic osteomyelitis. Isolated bacteria were Acinetobacter baumanii complex, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae

  15. Low-level laser therapy for treatment of neurosensory disorders after orthognathic surgery: A systematic review of randomized clinical trials.

    Science.gov (United States)

    Bittencourt, M-A-V; Paranhos, L-R; Martins-Filho, P-R-S

    2017-11-01

    Low-level laser has been widely used in Dentistry and many studies have focused on its application in oral surgeries. This study was conducted with the aim of searching for scientific evidence concerning the effectiveness of laser to reduce pain or paresthesia related to orthognathic surgery. An electronic search was performed in PubMed, Scopus, Science Direct, LILACS, SciELO, CENTRAL, Google Scholar, OpenGrey, and ClinicalTrials.gov, up to November 2016, with no restrictions on language or year of publication. Additionally, a hand search of the reference list of the selected studies was carried out. The PICOS strategy was used to define the eligibility criteria and only randomized clinical trials were selected. Out of 1,257 identified citations, three papers fulfilled the criteria and were included in the systematic review. The risk of bias was assessed according to the Cochrane Guidelines for Clinical Trials and results were exposed based on a descriptive analysis. One study showed that laser therapy was effective to reduce postoperative pain 24 hours (P=0.007) and 72 hours (P=0.007) after surgery. Other study revealed the positive effect of laser to improve neurosensory recovery 60 days after surgery, evaluated also by the two-point discrimination (P=0.005) and sensory (P=0.008) tests. The third study reported an improvement for general sensibility of 68.75% for laser group, compared with 21.43% for placebo (P=0.0095), six months after surgery. Individual studies suggested a positive effect of low-level laser therapy on reduction of postoperative pain and acceleration of improvement of paresthesia related to orthognathic surgery. However, due to the insufficient number and heterogeneity of studies, a meta-analysis evaluating the outcomes of interest was not performed, and a pragmatic recommendation about the use of laser therapy is not possible. This systematic review was conducted according to the statements of PRISMA and was registered at PROSPERO under the

  16. A Comparative Evaluation of Low-Level Laser and Topical Steroid Therapies for the Treatment of Erosive-Atrophic Lichen Planus.

    Science.gov (United States)

    El Shenawy, Hanaa M; Eldin, Amany Mohy

    2015-09-15

    Oral lichen planus (OLP) is a chronic inflammatory disease that causes bilateral white striations, papules, or plaques on the buccal mucosa, tongue, and gingivae. Erythema, erosions, and blisters may or may not be present. Several empirical therapies have been used in the treatment of (OLP). To evaluate the effect of low level laser therapy (LLLT) versus topical steroids for the treatment of erosive-atrophic lichen planus. Twenty-four patients with erosive-atrophic (OLP) were categorized into two groups. In the first group patients were treated with 970 nm diode laser irradiation, while, in the second group patients used topical corticosteroids (0.1% triamcinolone acetonide orabase). The gender, medical history and pain score were recorded. The pain score was measured before and after treatment by visual analogue scale (VAS). Steroid-treated group (0.1% triamcinolone acetonide orabase) show reduced pain score than laser group. Topical steroids are more effective than LLLT. LLLT may be used as an alternative treatment for symptomatic OLP when steroids are contraindicated.

  17. Transcranial low-level laser therapy increases memory, learning, neuroprogenitor cells, BDNF and synaptogenesis in mice with traumatic brain injury

    Science.gov (United States)

    Xuan, Weijun; Huang, Liyi; Vatansever, Fatma; Agrawal, Tanupriya; Hamblin, Michael R.

    2015-03-01

    Increasing concern is evident over the epidemic of traumatic brain injury in both civilian and military medicine, and the lack of approved treatments. Transcranial low level laser therapy tLLLT) is a new approach in which near infrared laser is delivered to the head, penetrates the scalp and skull to reach the brain. We asked whether tLLLT at 810-nm could improve memory and learning in mice with controlled cortical impact traumatic brain injury. We investigated the mechanism of action by immunofluorescence studies in sections from brains of mice sacrificed at different times. Mice with TBI treated with 1 or 3 daily laser applications performed better on Morris Water Maze test at 28 days. Laser treated mice had increased BrdU incorporation into NeuN positive cells in the dentate gyrus and subventricular zone indicating formation of neuroprogenitor cells at 7 days and less at 28 days. Markers of neuron migration (DCX and Tuj1) were also increased, as was the neurotrophin, brain derived neurotrophic factor (BDNF) at 7 days. Markers of synaptogenesis (formation of new connections between existing neurons) were increased in the perilesional cortex at 28 days. tLLLT is proposed to be able to induce the brain to repair itself after injury. However its ability to induce neurogenesis and synaptogenesis suggests that tLLLT may have much wider applications to neurodegenerative and psychiatric disorders.

  18. Comparative analysis of the number of neurofilaments in rat sciatic nerve undergoing neuropraxia treated by low-level laser and therapeutic ultrasound

    International Nuclear Information System (INIS)

    Matamala, F; Cornejo, R; Paredes, M; Farfan, E; Garrido, O. S; Alves, N

    2014-01-01

    Therapy by low-level laser (LLL) or ultrasound (US) are commonly used as treatment after nerve crush. The aim of this study was to determine the effectiveness of such treatments to repair the neuronal cytoskeleton evaluating the variation in the number of neurofilaments. For this an experimental design was performed, which involved 30 rats divided into 6 groups: 1 - control healthy; 2 - control injured; 3 - irradiated by LLL 2 J/cm2; 4 - irradiated by LLL 10 J/cm2; 5 - irradiated by US 0.5 W/cm2 and 6 - irradiated by US 1W/cm2. With the exception of group 1 all specimens were anesthetized and underwent right sciatic nerve compression using 40N pressure for 45 seconds. Twenty-four hours after compression irradiation was started by LLL and US according protocol. In our research we found that the increase in the number of neurofilaments was related to the applied dose of LLL and US. The average value of neurofilaments / 0.25 mm2 obtained in each group was: 1 - 128; 2-100; 3-156; 4-140; 5-100; 6-148. We concluded that the application of LLL and therapeutic US increases the number of neurofilaments in rat sciatic nerve undergoing neuropraxia, with LLL being more effective compared to the US. Furthermore we concluded that the effectiveness of therapies to induce regeneration of injured nerve is related to the type of protocol used, demonstrating the need to establish an adequate radiation dose with the purpose of obtaining the best therapeutic response, thus achieving successful treatment [es

  19. Hippocampal development in the rat: cytogenesis and morphogenesis examined with autoradiography and low-level x-irradiation

    International Nuclear Information System (INIS)

    Bayer, S.A.; Altman, J.

    1974-01-01

    The cytogenesis and morphogenesis of the rat hippocampus was examined with the techniques of 3 H-thymidine autoradiography, cell pyknosis produced by low-level x-irradiation, and quantitative histology. The procedure of progressively delayed cumulative labelling was used for autoradiography. Groups of rats were injected with four successive daily doses of 3 H-thymidine during non-overlapping periods ranging from birth to day 19. They were killed at 60 days of age, and the percentage of labelled cells was determined. Cell pyknosis in Ammon's horn reaches a maximal level prenatally and declines rapidly during the early postnatal period. Cell pyknosis in the dentate gyrus reaches its highest level during the second postnatal week and declines gradually with some radiosensitive cells still present in the adult. Immature granule cells are also at their highest level during the second postnatal week, while mature granule cells gradually accumulate to attain asymptotic levels at around two months of age. The alignment of the pyramidal cells to form the characteristic curvature of Ammon's horn occurs shortly after pyramidal cell cytogenesis is completed. Mechanisms for the morphological development of the dentate gyrus along with a consideration of the possible migratory route of granule cell precursors are discussed. (U.S.)

  20. Evaluation of low level laser and interferential current in the therapy of complex regional pain syndrome by infrared thermographic camera

    Directory of Open Access Journals (Sweden)

    Kocić Mirjana

    2010-01-01

    Full Text Available Background/Aim. Complex regional pain syndrome type I (CRPS I is characterized by continuous regional pain, disproportional according to duration and intensity and to the sort of trauma or other lesion it was caused by. The aim of the study was to evaluate and compare, by using thermovison, the effects of low level laser therapy and therapy with interferential current in treatment of CRPS I. Methods. The prospective randomized controlled clinical study included 45 patients with unilateral CRPS I, after a fracture of the distal end of the radius, of the tibia and/or the fibula, treated in the Clinical Centre in Nis from 2004 to 2007. The group A consisted of 20 patients treated by low level laser therapy and kinesy-therapy, while the patients in the group B (n = 25 were treated by interferential current and kinesy-therapy. The regions of interest were filmed by a thermovision camera on both sides, before and after the 20 therapeutic procedures had been applied. Afterwards, the quantitative analysis and the comparing of thermograms taken before and after the applied therapy were performed. Results. There was statistically significant decrease of the mean maximum temperature difference between the injured and the contralateral extremity after the therapy in comparison to the status before the therapy, with the patients of the group A (p < 0.001 as well as those of the group B (p < 0.001. The decrease was statistically significantly higher in the group A than in the group B (p < 0.05. Conclusions. By the use of the infrared thermovision we showed that in the treatment of CRPS I both physical medicine methods were effective, but the effectiveness of laser therapy was statistically significantly higher compared to that of the interferential current therapy.

  1. Amelioration of cardiac function and activation of anti-inflammatory vasoactive peptides expression in the rat myocardium by low level laser therapy.

    Directory of Open Access Journals (Sweden)

    Martha Trindade Manchini

    Full Text Available Low-level laser therapy (LLLT has been used as an anti-inflammatory treatment in several disease conditions, even when inflammation is a secondary consequence, such as in myocardial infarction (MI. However, the mechanism by which LLLT is able to protect the remaining myocardium remains unclear. The present study tested the hypothesis that LLLT reduces inflammation after acute MI in female rats and ameliorates cardiac function. The potential participation of the Renin-Angiotensin System (RAS and Kallikrein-Kinin System (KKS vasoactive peptides was also evaluated. LLLT treatment effectively reduced MI size, attenuated the systolic dysfunction after MI, and decreased the myocardial mRNA expression of interleukin-1 beta and interleukin-6 in comparison to the non-irradiated rat tissue. In addition, LLLT treatment increased protein and mRNA levels of the Mas receptor, the mRNA expression of kinin B2 receptors and the circulating levels of plasma kallikrein compared to non-treated post-MI rats. On the other hand, the kinin B1 receptor mRNA expression decreased after LLLT. No significant changes were found in the expression of vascular endothelial growth factor (VEGF in the myocardial remote area between laser-irradiated and non-irradiated post-MI rats. Capillaries density also remained similar between these two experimental groups. The mRNA expression of the inducible nitric oxide synthase (iNOS was increased three days after MI, however, this effect was blunted by LLLT. Moreover, endothelial NOS mRNA content increased after LLLT. Plasma nitric oxide metabolites (NOx concentration was increased three days after MI in non-treated rats and increased even further by LLLT treatment. Our data suggest that LLLT diminishes the acute inflammation in the myocardium, reduces infarct size and attenuates left ventricle dysfunction post-MI and increases vasoactive peptides expression and nitric oxide (NO generation.

  2. Amelioration of Cardiac Function and Activation of Anti-Inflammatory Vasoactive Peptides Expression in the Rat Myocardium by Low Level Laser Therapy

    Science.gov (United States)

    Manchini, Martha Trindade; Serra, Andrey Jorge; Feliciano, Regiane dos Santos; Santana, Eduardo Tadeu; Antônio, Ednei Luis; de Tarso Camillo de Carvalho, Paulo; Montemor, Jairo; Crajoinas, Renato Oliveira; Girardi, Adriana Castello Costa; Tucci, Paulo José Ferreira; Silva, José Antônio

    2014-01-01

    Low-level laser therapy (LLLT) has been used as an anti-inflammatory treatment in several disease conditions, even when inflammation is a secondary consequence, such as in myocardial infarction (MI). However, the mechanism by which LLLT is able to protect the remaining myocardium remains unclear. The present study tested the hypothesis that LLLT reduces inflammation after acute MI in female rats and ameliorates cardiac function. The potential participation of the Renin-Angiotensin System (RAS) and Kallikrein-Kinin System (KKS) vasoactive peptides was also evaluated. LLLT treatment effectively reduced MI size, attenuated the systolic dysfunction after MI, and decreased the myocardial mRNA expression of interleukin-1 beta and interleukin-6 in comparison to the non-irradiated rat tissue. In addition, LLLT treatment increased protein and mRNA levels of the Mas receptor, the mRNA expression of kinin B2 receptors and the circulating levels of plasma kallikrein compared to non-treated post-MI rats. On the other hand, the kinin B1 receptor mRNA expression decreased after LLLT. No significant changes were found in the expression of vascular endothelial growth factor (VEGF) in the myocardial remote area between laser-irradiated and non-irradiated post-MI rats. Capillaries density also remained similar between these two experimental groups. The mRNA expression of the inducible nitric oxide synthase (iNOS) was increased three days after MI, however, this effect was blunted by LLLT. Moreover, endothelial NOS mRNA content increased after LLLT. Plasma nitric oxide metabolites (NOx) concentration was increased three days after MI in non-treated rats and increased even further by LLLT treatment. Our data suggest that LLLT diminishes the acute inflammation in the myocardium, reduces infarct size and attenuates left ventricle dysfunction post-MI and increases vasoactive peptides expression and nitric oxide (NO) generation. PMID:24991808

  3. Efficacy of low-level laser therapy for the treatment of burning mouth syndrome: a randomized, controlled trial

    Science.gov (United States)

    Spanemberg, Juliana Cassol; López, José López; de Figueiredo, Maria Antonia Zancanaro; Cherubini, Karen; Salum, Fernanda Gonçalves

    2015-09-01

    The aim of the present study was to assess the effect of low-level laser therapy (LLLT) in the treatment of burning mouth syndrome (BMS). A diode laser was used in 78 BMS patients who were randomly assigned into four groups: IR1W, n=20 (830 nm, 100 mW, 5 J, 176 J/cm2, 50 s, LLLT weekly sessions, 10 sessions); IR3W, n=20 (830 nm, 100 mW, 5 J, 176 J/cm2, 50 s, three LLLT weekly sessions, 9 sessions); red laser, n=19 (685 nm, 35 mW, 2 J, 72 J/cm2, 58 s, three LLLT weekly sessions, 9 sessions); and control-group (CG), n=19. Symptoms were assessed at the end of the treatment and eight weeks later; quality of life related to oral health was assessed using the Oral Health Impact Profile (OHIP-14). Statistical analysis was carried out using repeated measures analysis of variance followed by the posthoc Tukey test. There was significant reduction of the symptoms in all groups at the end of the treatment, which was maintained in the follow-up. The scores of the IR1W and IR3W laser groups differed significantly from those of the CG. There was also a decrease in the OHIP-14 scores in the four groups. The IR3W laser group scores differed significantly from those of the CG. LLLT reduces the symptoms of BMS and may be an alternative therapeutic strategy for the relief of symptoms in patients with BMS.

  4. Low-level laser therapy with helium-neon laser improved viability of osteoporotic bone marrow-derived mesenchymal stem cells from ovariectomy-induced osteoporotic rats

    Science.gov (United States)

    Fallahnezhad, Somaye; Piryaei, Abbas; Tabeie, Faraj; Nazarian, Hamid; Darbandi, Hasan; Amini, Abdoldllah; Mostafavinia, Ataroalsadat; Ghorishi, Seyed Kamran; Jalalifirouzkouhi, Ali; Bayat, Mohammad

    2016-09-01

    The purpose of this study was to evaluate the influences of helium-neon (He-Ne) and infrared (IR) lasers on the viability and proliferation rate of healthy and ovariectomy-induced osteoporotic (OVX) bone marrow mesenchymal stem cells (BMMSCs) in vitro. MSCs harvested from the BM of healthy and OVX rats were culture expanded. He-Ne and IR lasers were applied three times at energy densities of 0.6, 1.2, and 2.4 J/cm2 for BMMSCs. BMMSCs viability and proliferation rate were evaluated by MTT assay on days 2, 4, 6, 14, and 21. The results showed that healthy BMMSCs responded optimally to 0.6 J/cm2 using an IR laser after three times of laser radiation. Moreover, it was found that OVX-BMMSCs responded optimally to 0.6 J/cm2 with He-Ne laser and one-time laser radiation. It is concluded that the low-level laser therapy (LLLT) effect depends on the physiological state of the BMMSCs, type of the laser, wavelength, and number of laser sessions. The biostimulation efficiency of LLLT also depends on the delivered energy density. LLLT can enhance the viability and proliferation rate of healthy and especially osteoporotic autologous BMMSCs, which could be very useful in regenerative medicine.

  5. Effect of low-level laser therapy on tissue repair after dental extraction in rats administered zoledronic acid and dexamethasone

    Science.gov (United States)

    Weber, João Batista Blessmann; Camilotti, Renata Stifelman; Jasper, Juliana; Casagrande, Liliane Cristina Onofre; Maito, Fábio Luiz Dal Moro

    2017-05-01

    Bisphosphonates (BPs) are being increasingly used for the treatment of metabolic and oncological pathologies involving the skeletal system. Because of the severity of the BP associated osteonecrosis of the jaws, the difficulties of treatment, and patient discomfort, additional support methods for their management are needed. Laser therapy has an easy handling, photobiostimulator effect on tissues healing, so it can be considered a preferred therapy. The aim of this study was to evaluate the influence of low-level laser therapy in the 685- and 830-nm wavelength in the healing process of the bone and soft tissues in rats under BP therapy [zoledronic acid (ZA)] and dexamethasone concomitantly that underwent a surgery for the extraction of upper molars. There were statistically significant differences in the clinical evaluation of the wound and the weight of the animals. Regarding the histological evaluation, it was possible to observe the different maturations of the healing stage between groups. The effect of drug therapy with ZA and dexamethasone in the bone tissue repair process induces osteonecrosis of the jaw in rats and slows down the healing process. In the laser groups, at the stipulated dosimetry, a positive influence on the bone and soft tissue repair process was observed.

  6. Low-level laser therapy effects on pain perception related to the use of orthodontic elastomeric separators

    Directory of Open Access Journals (Sweden)

    Rachel D'Aurea Furquim

    2015-06-01

    Full Text Available INTRODUCTION: Some patients refer to pre-banding orthodontic separation as a painful orthodontic procedure. Low-level laser therapy (LLLT has been reported to have local analgesic effect. OBJECTIVE: The aim of this single-blind study was to investigate the perception of pain caused by orthodontic elastomeric separators with and without a single LLLT application (6J. METHODS: The sample comprised 79 individuals aged between 13 and 34 years old at orthodontic treatment onset. Elastomeric separators were placed in first maxillary molars at mesial and distal surfaces and kept in place for three days. The volunteers scored pain intensity on a visual analogue scale (VAS after 6 and 12 hours, and after the first, second and third days. One third of patients received laser applications, whereas another third received placebo applications and the remaining ones were controls. Applications were performed in a split-mouth design. Thus, three groups (laser, placebo and control were assessed. RESULTS: No differences were found among groups considering pain perception in all periods observed. CONCLUSION: The use of a single-dose of LLLT did not cause significant reduction in orthodontic pain perception. Overall pain perception due to orthodontic separator placement varied widely and was usually mild.

  7. The effects of transcutaneous low-level laser therapy on the skin healing process: an experimental model.

    Science.gov (United States)

    Ramos, Felipe Scholz; Maifrino, Laura Beatriz Mesiano; Alves, Sarah; da Costa Aguiar Alves, Beatriz; Perez, Matheus Moreira; Feder, David; Azzalis, Ligia Ajaime; Junqueira, Virginia Berlanga Campos; Fonseca, Fernando Luiz Affonso

    2018-01-06

    We aim to evaluate the action of transcutaneous laser in the initial wound healing process. The use of low-level laser therapy (LLLT) has proven to be effective on inflammatory modulation and wound healing. The trial was performed on five groups of rats, through a dorsal incision. All groups received treatment on auricular artery. Groups 1 and 3 were treated with transcutaneous LLLT over a period of 15 min. Groups 2 and 4 received one and two inactive laser applications (placebo), respectively. Group 5 was the control one. Blood samples were collected 2 h after the last application of LLLT so that cytokine levels could be measured by ELISA. Tissue fragments were harvested for morphometric, histomorphometric, and RT-qPCR analyses. The morphometric analysis revealed a greater decrease in the wounded area in G1 when compared with G2, whereas in G3, the improvement in the area was greater when compared with G4. Finally, the histomorphometric analysis showed that G1 was the group closer to G5 in terms of collagen fiber count. G2 and G4 had higher amounts of collagen fibers than G5 while G3 had a lower quantity. The use of the transcutaneous LLLT in the current study influenced the wound healing process.

  8. An investigation into the depth of penetration of low level laser therapy through the equine tendon in vivo

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    Ryan Teresa

    2007-05-01

    Full Text Available Abstract Low level laser therapy (LLLT is frequently used in the treatment of wounds, soft tissue injury and in pain management. The exact penetration depth of LLLT in human tissue remains unspecified. Similar uncertainty regarding penetration depth arises in treating animals. This study was designed to test the hypothesis that transmission of LLLT in horses is increased by clipping the hair and/or by cleaning the area to be treated with alcohol, but is unaffected by coat colour. A LLLT probe (810 nm, 500 mW was applied to the medial aspect of the superficial flexor tendon of seventeen equine forelimbs in vivo. A light sensor was applied to the lateral aspect, directly opposite the laser probe to measure the amount of light transmitted. Light transmission was not affected by individual horse, coat colour or leg. However, it was associated with leg condition (F = 4.42, p = 0.0032. Tendons clipped dry and clipped and cleaned with alcohol, were both associated with greater transmission of light than the unprepared state. Use of alcohol without clipping was not associated with an increase in light transmission. These results suggest that, when applying laser to a subcutaneous structure in the horse, the area should be clipped and cleaned beforehand.

  9. Low-level laser therapy activates NF-kB via generation of reactive oxygen species in mouse embryonic fibroblasts.

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    Aaron C-H Chen

    Full Text Available Despite over forty years of investigation on low-level light therapy (LLLT, the fundamental mechanisms underlying photobiomodulation at a cellular level remain unclear.In this study, we isolated murine embryonic fibroblasts (MEF from transgenic NF-kB luciferase reporter mice and studied their response to 810 nm laser radiation. Significant activation of NF-kB was observed at fluences higher than 0.003 J/cm(2 and was confirmed by Western blot analysis. NF-kB was activated earlier (1 hour by LLLT compared to conventional lipopolysaccharide treatment. We also observed that LLLT induced intracellular reactive oxygen species (ROS production similar to mitochondrial inhibitors, such as antimycin A, rotenone and paraquat. Furthermore, we observed similar NF-kB activation with these mitochondrial inhibitors. These results, together with inhibition of laser induced NF-kB activation by antioxidants, suggests that ROS play an important role in the laser induced NF-kB signaling pathways. However, LLLT, unlike mitochondrial inhibitors, induced increased cellular ATP levels, which indicates that LLLT also upregulates mitochondrial respiration.We conclude that LLLT not only enhances mitochondrial respiration, but also activates the redox-sensitive NFkB signaling via generation of ROS. Expression of anti-apoptosis and pro-survival genes responsive to NFkB could explain many clinical effects of LLLT.

  10. Effectiveness of Low-Level Laser Therapy in Reducing Orthodontic Pain: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Deana, Naira Figueiredo; Zaror, Carlos; Sandoval, Paulo

    2017-01-01

    Objectives To assess the effectiveness of low-level laser therapy (LLLT) in reducing orthodontic pain after the application of orthodontic force (OF). Methods A systematic search was conducted in the MEDLINE, EMBASE, Scopus, Cochrane Library, Web of Science, and EBSCOhost databases. The study included randomized clinical trials (RCT) which analysed the effectiveness of LLLT in reducing orthodontic pain assessed at 24 and 72 hrs after the application of OF. The risk of bias of the eligible trials was assessed using the Cochrane Collaboration's risk of bias tool. Standard mean difference was calculated and pooled by meta-analysis using random effect models. Results Of 467 identified articles, 20 RCT were finally included. In the risk of bias assessments, 13 studies presented a high risk, 5 an unclear risk, and 2 a low risk. The meta-analysis showed that in patients treated with laser versus placebo there was a difference in favour of LLLT in spontaneous pain 24 and 72 hrs after the installation of light archwires and spontaneous pain and chewing pain 24 and 72 hrs after the installation of elastomeric separators. Conclusions LLLT proved to be effective in promoting a reduction in spontaneous and chewing pain after the application of OF; however, the poor quality of the evidence requires these results to be treated with caution. PMID:29089818

  11. Use of low-level laser therapy as monotherapy or concomitant therapy for male and female androgenetic alopecia.

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    Munck, Andréia; Gavazzoni, Maria Fernanda; Trüeb, Ralph M

    2014-04-01

    Androgenetic alopecia (AGA) is the most common form of hair loss in men and in women. Currently, minoxidil and finasteride are the treatments with the highest levels of medical evidence, but patients who exhibit intolerance or poor response to these treatments are in need of additional treatment modalities. The aim was to evaluate the efficacy and safety of low-level laser therapy (LLLT) for AGA, either as monotherapy or as concomitant therapy with minoxidil or finasteride, in an office-based setting. Retrospective observational study of male and female patients with AGA, treated with the 655 nm-HairMax Laser Comb(®), in an office-based setting. Efficacy was assessed with global photographic imaging. Of 32 patients (21 female, 11 male), 8 showed significant, 20 moderate, and 4 no improvement. Improvement was seen both with monotherapy and with concomitant therapy. Improvement was observed as early as 3 months and was sustained up to a maximum observation time of 24 months. No adverse reactions were reported. LLLT represents a potentially effective treatment for both male and female AGA, either as monotherapy or concomitant therapy. Combination treatments with minoxidil, finasteride, and LLLT may act synergistic to enhance hair growth.

  12. Low-level lasers on microRNA and uncoupling protein 2 mRNA levels in human breast cancer cells

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    Canuto, K. S.; Teixeira, A. F.; Rodrigues, J. A.; Paoli, F.; Nogueira, E. M.; Mencalha, A. L.; Fonseca, A. S.

    2017-06-01

    MicroRNA is short non-coding RNA and is a mediator of post-transcriptional regulation of gene expression. In addition, uncoupling proteins (UCPs) regulate thermogenesis, metabolic and energy balance, and decrease reactive oxygen species production. Both microRNA and UCP2 expression can be altered in cancer cells. At low power, laser wavelength, frequency, fluence and emission mode deternube photobiological responses, which are the basis of low-level laser therapy. There are few studies on miRNA and UCP mRNA levels after low-level laser exposure on cancer cells. In this work, we evaluate the micrRNA (mir-106b and mir-15a) and UCP2 mRNA levels in human breast cancer cells exposed to low-level lasers. MDA-MB-231 human breast cancer cells were exposed to low-level red and infrared lasers, total RNA was extracted for cDNA synthesis and mRNA levels by real time quantitative polymerase chain reaction were evaluated. Data show that mir-106b and mir-15a relative levels are not altered, but UCP2 mRNA relative levels are increased in MDA-MB-231 human breast cancer cells exposed to low-level red and infrared lasers at fluences used in therapeutic protocols.

  13. Sapphire capillary interstitial irradiators for laser medicine

    Science.gov (United States)

    Shikunova, I. A.; Dolganova, I. N.; Dubyanskaya, E. N.; Mukhina, E. E.; Zaytsev, K. I.; Kurlov, V. N.

    2018-04-01

    In this paper, we demonstrate instruments for laser radiation delivery based on sapphire capillary needles. Such sapphire irradiators (introducers) can be used for various medical applications, such as photodynamic therapy, laser hyperthermia, laser interstitial thermal therapy, and ablation of tumors of various organs. Unique properties of sapphire allow for effective redistribution of the heat, generated in biological tissues during their exposure to laser radiation. This leads to homogeneous distribution of the laser irradiation around the needle, and lower possibility of formation of the overheating focuses, as well as the following non-transparent thrombi.

  14. Low-level laser therapy (LLLT) accelerates the sternomastoid muscle regeneration process after myonecrosis due to bupivacaine.

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    Alessi Pissulin, Cristiane Neves; Henrique Fernandes, Ana Angélica; Sanchez Orellana, Alejandro Manuel; Rossi E Silva, Renata Calciolari; Michelin Matheus, Selma Maria

    2017-03-01

    Because of its long-lasting analgesic action, bupivacaine is an anesthetic used for peripheral nerve block and relief of postoperative pain. Muscle degeneration and neurotoxicity are its main limitations. There is strong evidence that low-level laser therapy (LLLT) assists in muscle and nerve repair. The authors evaluated the effects of a Gallium Arsenide laser (GaAs), on the regeneration of muscle fibers of the sternomastoid muscle and accessory nerve after injection of bupivacaine. In total, 30 Wistar adult rats were divided into 2 groups: control group (C: n=15) and laser group (L: n=15). The groups were subdivided by antimere, with 0.5% bupivacaine injected on the right and 0.9% sodium chloride on the left. LLLT (GaAs 904nm, 0,05W, 2.8J per point) was administered for 5 consecutive days, starting 24h after injection of the solutions. Seven days after the trial period, blood samples were collected for determination of creatine kinase (CK). The sternomastoid nerve was removed for morphological and morphometric analyses; the surface portion of the sternomastoid muscle was used for histopathological and ultrastructural analyses. Muscle CK and TNFα protein levels were measured. The anesthetic promoted myonecrosis and increased muscle CK without neurotoxic effects. The LLLT reduced myonecrosis, characterized by a decrease in muscle CK levels, inflammation, necrosis, and atrophy, as well as the number of central nuclei in the muscle fibers and the percentage of collagen. TNFα values remained constant. LLLT, at the dose used, reduced fibrosis and myonecrosis in the sternomastoid muscle triggered by bupivacaine, accelerating the muscle regeneration process. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Transcranial low-level laser therapy improves brain mitochondrial function and cognitive impairment in D-galactose-induced aging mice.

    Science.gov (United States)

    Salehpour, Farzad; Ahmadian, Nahid; Rasta, Seyed Hossein; Farhoudi, Mehdi; Karimi, Pouran; Sadigh-Eteghad, Saeed

    2017-10-01

    Mitochondrial function plays a key role in the aging-related cognitive impairment, and photoneuromodulation of mitochondria by transcranial low-level laser therapy (LLLT) may contribute to its improvement. This study focused on the transcranial LLLT effects on the D-galactose (DG)-induced mitochondrial dysfunction, apoptosis, and cognitive impairment in mice. For this purpose, red and near-infrared (NIR) laser wavelengths (660 and 810 nm) at 2 different fluencies (4 and 8 J/cm 2 ) at 10-Hz pulsed wave mode were administrated transcranially 3 d/wk in DG-received (500 mg/kg/subcutaneous) mice model of aging for 6 weeks. Spatial and episodic-like memories were assessed by the Barnes maze and What-Where-Which (WWWhich) tasks. Brain tissues were analyzed for mitochondrial function including active mitochondria, adenosine triphosphate, and reactive oxygen species levels, as well as membrane potential and cytochrome c oxidase activity. Apoptosis-related biomarkers, namely, Bax, Bcl-2, and caspase-3 were evaluated by Western blotting method. Laser treatments at wavelengths of 660 and 810 nm at 8 J/cm 2 attenuated DG-impaired spatial and episodic-like memories. Also, results showed an obvious improvement in the mitochondrial function aspects and modulatory effects on apoptotic markers in aged mice. However, same wavelengths at the fluency of 4 J/cm 2 had poor effect on the behavioral and molecular indexes in aging model. This data indicates that transcranial LLLT at both of red and NIR wavelengths at the fluency of 8 J/cm 2 has a potential to ameliorate aging-induced mitochondrial dysfunction, apoptosis, and cognitive impairment. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Effects of low-level laser therapy in combination with physiotherapy in the management of rotator cuff tendinitis.

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    Eslamian, Fariba; Shakouri, Seyyed Kazem; Ghojazadeh, Morteza; Nobari, Ozra Eslampanah; Eftekharsadat, Bina

    2012-09-01

    Rotator cuff tendinitis is one of the main causes of shoulder pain. The objective of this study was to evaluate the possible additive effects of low-power laser treatment in combination with conventional physiotherapy endeavors in these patients. A total of 50 patients who were referred to the Physical Medicine and Rehabilitation Clinic with shoulder pain and rotator cuff disorders were selected. Pain severity measured with visual analogue scale (VAS), abduction, and external rotation range of motion in shoulder joint was measured by goniometry, and evaluation of daily functional abilities of patients was measured by shoulder disability questionnaire. Twenty-five of the above patients were randomly assigned into the control group and received only routine physiotherapy. The other 25 patients were assigned into the experimental group and received conventional therapy plus low-level laser therapy (4 J/cm(2) at each point over a maximum of ten painful points of shoulder region for total 5 min duration). The above measurements were assessed at the end of the third week of therapy in each group and the results were analyzed statistically. In both groups, statistically significant improvement was detected in all outcome measures compared to baseline (p rotation (78.0 ± 19.5 vs. 76.3 ± 19.1) had no significant difference between the two groups (p = 0.20 and 0.77, respectively). As one of physical modalities, gallium-arsenide low-power laser combined with conventional physiotherapy has superiority over routine physiotherapy from the view of decreasing pain and improving the patient's function, but no additional advantages were detected in increasing shoulder joint range of motion in comparison to other physical agents.

  17. Clinical results from low-level laser therapy in patients with autosomal dominant cone-rod dystrophy

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    Koev, K.; Avramov, L.; Borissova, E.

    2018-03-01

    The objective of this study is to examine long-term effects of low-level laser therapy (LLLT) in patients with autosomal dominant cone-rod dystrophy (CRDs). A He-Ne Laser with continuous emission at 633 nm (01 mW/cm2) was used on five patients with autosomal dominant pedigree of Romani origin with non-syndromic CRDs. The laser radiation was applied transpupillary to the macula six times for three minutes every other day. The experiment was conducted for a period of three years. The clinical evaluation included best corrected visual acuity determination, funduscopy, Humphrey perimetry, Farnsworth Hue-28 color testing, fluorescein angiography, and full-field electroretinogram (ERG). All affected individuals presented reduced visual acuity (0.01 – 0.4) and photophobia. The funduscopic examination and fluorescein angiography revealed advanced changes including bone spicule-like pigment deposits in the midperiphery and the macular area, along with retinal atrophy, narrowing of the vessels, and waxy optic discs. The visual fields demonstrated central scotoma. The electrophysiologic examination of the patients detected an abnormal cone-rod ERG (20 – 30 μV) with photopic amplitudes more markedly reduced than the scotopic. Flicker responses were missing and Farnsworth Hue-28 test found protanopia. There was a statistically significant increase in the visual acuity (p<0.001, end of study versus baseline) for CRDs patients for the period of three years after the treatment with LLLT. Following the LLLT, the central absolute scotoma in CRDs was reduced, as was the prevalence of metamorphopsia in CRDs. This study shows that LLLT may prove be a novel long-lasting therapeutic option for both forms of CRDs. It is a highly effective treatment resulting in a long-term improvement of the visual acuity.

  18. To evaluate the safety and efficiency of low level laser therapy (LLLT) in treating decubitus ulcers: a review

    Science.gov (United States)

    Ahmed, Ambereen

    2015-03-01

    Introduction: Pressure sores (decubitus ulcer) are a serious problem in health care management, especially for middleaged to older people who are bed-ridden. Although preventative measures are used, the condition remains common and development of novel, improved treatment methods are desirable. This article reviews the application of laser-based methods, previously shown to be effective in accelerating wound-healing in animal models and in the treatment of decubitus ulcers in humans. Methods: About 23 scientific articles on the effect of low level laser therapy (LLLT) on wound healing in animals and humans from 2000-2014 were reviewed. Additionally, results of several randomized controlled trials (RCTs) were reviewed, and compared with other treatment methods available. Results: Whilst carefully controlled, laboratory-based animal studies indicated that LLLT can reduce healing time for several types of injuries, however similar studies in humans failed to demonstrate consistent beneficial effects in the clinical setting. An acceleration of decubitus ulcer healing has been occasionally found, although limited to certain wavelengths and sometimes only in combination with other types of therapies. Indeed, some of the clinical articles indicated that certain laser wavelengths can have detrimental effects on time of healing. Conclusions: To date, there remains no convincing evidence that LLLT has consistent medical benefit in treating decubitus ulcers. Caution should be applied when considering LLLT since only certain wavelengths utilized have shown beneficial effects. It is concluded that, more RCTs are needed since, there is no clinical justification for LLLT, alone or in combination with other methods, in treating decubitus ulcers.

  19. Cochlea hair cell rescue after a noise-induced hearing loss using a low level laser therapy (LLLT)

    Science.gov (United States)

    Rhee, Chung-Ku; Bahk, Chan Woong; Jung, Jae Yun; Ahn, Jin-Chul; Suh, Myung-Whan

    2011-03-01

    Aim: To see the effect of LLLT on noise-induced hearing loss. Methods: Eleven rats were exposed to noise (120 dB, 16 kHz, 6 h) and left ears were irradiated at 60J/cm2, 830 nm laser for 12 days. Right ears were control. Hearing levels were measured at frequencies of 4, 8, 12, 16, 32 kHz before noise exposure and after 12th irradiations. Results: The initial hearing levels were 26.5+/-4.7, 24.5+/-5.0, 24.0+/-5.2, 24.0+/-3.2, 24.5+/-5.5 dB SPL. After noise exposure, thresholds were 63.5+/-15.1, 64+/-16.8, 71.5+/-11.3, 73.5+/-15.6, 67.5+/-14.4 dB SPL in 4, 8, 12, 16, 32 kHz. After 12th irradiation, thresholds of treated ears recovered significantly 21+/-4.2, 20+/-3.5, 24+/-11.9, 24+/-12.9, 21+/-2.2 dB SPL and that of the untreated right ears measured 36.3+/-22.9, 45+/-15.8, 66.3+/-22.9, 50+/-16.8, 43.8+/-21.4 dB SPL. Conclusion: LLLT may promote recovery of hearing after noiseinduced hearing loss.

  20. In Vitro UV-Visible Spectroscopy Study of Yellow Laser Irradiation on Human Blood

    Science.gov (United States)

    Fuad, Siti Sakinah Mohd; Suardi, N.; Mustafa, I. S.

    2018-04-01

    This experimental study was performed to investigate the effect of low level yellow laser of 589nm wavelength with various laser irradiation time. Human blood samples with random diseases are irradiated with yellow laser of power density of 450mW/cm2 from 10 minutes to 60 minutes at 10 minutes intervals. The morphology of the red blood cell were also observed for different irradiation time. The result shows that there is a significant different in the absorption of light with varying laser irradiation time (p<0.01). The maximum absorption recorded at 40 minutes of irradiation at 340nm peak. Blood smear of the samples reveals that there are observable changes in the morphology of the red blood cell at 40 minutes and 60 minutes of irradiation.

  1. Regional Lymphotropic Therapy in Combination with Low Level Laser Therapy for Treating Multi-Drug-Resistant Tuberculosis

    Directory of Open Access Journals (Sweden)

    Oksana Dogorova

    2016-03-01

    Full Text Available With the growing incidence of Multi-Drug-Resistant Tuberculosis (MDR-TB in newly identified patients, novel multimodality treatment methods are needed, aimed at reducing the time to sputum conversion and cavity healing, which would be applicable in MDR cases. Our experimental treatment consisted of the following: 1 chemotherapy based on the drug sensitivity profile, 2 local laser irradiation therapy for 25 days, and lymphotropic administration of isoniazid (to subcutaneous tissue in alternating locations: underarm area; fifth intercostal space along the sterna border; subclavian area where the first rib meets the sternum in a daily dose of 10mg/kg 5 times a week. This treatment was significantly more effective in newly detected destructive MDR-TB versus the standard Category IV regimen for MDR-TB in terms of reduced time for sputum culture conversion and cavity healing, estimated to be 6 months after initiation of treatment.

  2. Is low-level laser therapy in relieving neck pain effective? Systematic review and meta-analysis.

    Science.gov (United States)

    Kadhim-Saleh, Amjed; Maganti, Harinad; Ghert, Michelle; Singh, Sheila; Farrokhyar, Forough

    2013-10-01

    The aim of this study is to determine the efficacy of low-level laser therapy (LLLT) in reducing acute and chronic neck pain as measured by the visual analog scale (VAS). A systematic search of nine electronic databases was conducted to identify original articles. For study selection, two reviewers independently assessed titles, abstracts, and full text for eligibility. Methodological quality was assessed using the Detsky scale. Data were analyzed using random-effects model in the presence of heterogeneity and fixed-effect model in its absence. Heterogeneity was assessed using Cochran's Q statistic and quantifying I (2). Risk ratios (RR) with 95 % confidence intervals (CI) were reported. Eight randomized controlled trials involving 443 patients met the strict inclusion criteria. Inter-rater reliability for study selection was 92.8 % (95 % CIs 80.9-100 %) and for methodological quality assessment was 83.9 % (95 % CIs 19.4-96.8 %). Five trials included patients with cervical myofascial pain syndrome (CMPS), and three trials included different patient populations. A meta-analysis of five CMPS trials revealed a mean improvement of VAS score of 10.54 with LLLT (95 % CI 0.37-20.71; Heterogeneity I (2 )= 65 %, P = 0.02). This systematic review provides inconclusive evidence because of significant between-study heterogeneity and potential risk of bias. The benefit seen in the use of LLLT, although statistically significant, does not constitute the threshold of minimally important clinical difference.

  3. Low-Level Laser Therapy and Cryotherapy as Mono- and Adjunctive Therapies for Achilles Tendinopathy in Rats.

    Science.gov (United States)

    Haslerud, Sturla; Lopes-Martins, Rodrigo Alvaro Brandão; Frigo, Lúcio; Bjordal, Jan Magnus; Marcos, Rodrigo Labat; Naterstad, Ingvill Fjell; Magnussen, Liv Heide; Joensen, Jon

    2017-01-01

    Low-level laser therapy (LLLT) and cryotherapy are widely used treatments in the acute phase of tendon injury. The aim of this study was to investigate the interaction of these two treatments on tendon inflammation and mechanical properties. Six groups of six Wistar rats were used in this study. The Achilles tendons of the healthy control group were not subjected to injury or treatment. The tendons of the injured nontreated group (ING) were injured, but not treated. The remaining four groups were injured and subjected to LLLT, cryotherapy, LLLT first/cryotherapy, or cryotherapy first/LLLT. All treatments were performed at 1 h post-trauma. Inflammatory mediators, tendon histology, and biomechanical properties were assessed at 24 h post-trauma by comparing the treatment groups with the ING. In all treatment groups, the inflammatory process shifted in an anti-inflammatory direction compared with the ING. Significant alterations in cytokine expression were found in only the LLLT group (↓IL-1β) and the combined intervention groups (↓IL-1β, ↓TNF-α, ↑IL-6). It was also found that cryotherapy followed by LLLT was the only treatment that significantly (p cryotherapy in combination with LLLT can produce an anti-inflammatory "add-on" effect. The order of therapy administration seems essential, as superior histology and biomechanical results were found in the cryotherapy first/LLLT group.

  4. Evaluation of the low-level laser therapy application parameters for skin burn treatment in experimental model: a systematic review.

    Science.gov (United States)

    Brassolatti, Patricia; de Andrade, Ana Laura Martins; Bossini, Paulo Sérgio; Otterço, Albaiza Nicoletti; Parizotto, Nivaldo Antônio

    2018-05-05

    Burn is defined as a traumatic injury of thermal origin, which affects the organic tissue. Low-level laser therapy (LLLT) has gained great prominence as a treatment in this type of injury; however, the application parameters are still controversial in the literature. The aims of this study were to review the literature studies that use LLLT as a treatment in burns conducted in an experimental model, discuss the main parameters used, and highlight the benefits found in order to choose an appropriate therapeutic window to be applied in this type of injury. The selection of the studies related to the theme was carried out in the main databases (PubMed, Cochrane Library, LILACS, Web of Science, and Scopus in the period from 2001 to 2017). Subsequently, the articles were then chosen that fell within the inclusion criteria previously established. In the end, 22 were evaluated, and the main parameters were presented. The analyzed studies presented both LLLT use in continuous and pulsed mode. Differences between the parameters used (power, fluence, and total energy) were observed. In addition, the protocols are distinct as to the type of injury and the number of treatment sessions. Among the results obtained by the authors are the improvements in the local microcirculation and cellular proliferation; however, a study reported no effects with LLLT as a treatment. LLLT is effective in accelerating the healing process. However, there is immense difficulty in establishing the most adequate protocol, due to the great discrepancy found in the applied dosimetry values.

  5. A Critical Assessment of the Evidence for Low-Level Laser Therapy in the Treatment of Hair Loss.

    Science.gov (United States)

    Gupta, Aditya K; Foley, Kelly A

    2017-02-01

    Low-level laser therapy (LLLT) is currently in use to stimulate hair growth and is quickly gaining in popularity due to the ease of use and absence of side effects. In 2015 alone, the number of LLLT devices with the Food and Drug Administration clearance has doubled. To consolidate evidence and establish which data are still required for the widespread acceptance of LLLT for hair loss therapy. A thorough search of the PubMed database was conducted to obtain studies investigating LLLT for androgenetic alopecia in men and women. Nine trials were identified for comb and helmet/cap devices, five of which were randomized controlled trials. Data comparison across LLLT trials and with traditional hair loss therapy (minoxidil, finasteride) was not straight forward because there was a lack of visual evidence, sample sizes were low, and there were large variations in study duration and efficacy measurements. There are a number of unanswered questions about the optimum treatment regimen, including maintenance treatment and the long-term consequences of LLLT use. Moving forward, protocols should be standardized across trials. Moreover, it is recommended that future trials include visual evidence and trial duration be expanded to 12 months.

  6. Low-level laser therapy in the treatment of muscle-skelet pain in patients affected by temporo-mandibular disorders.

    Science.gov (United States)

    Basili, M; Barlattani, A; Venditti, A; Bollero, P

    2017-01-01

    The purpose of the study is to evaluate the effectiveness of Low-Level Laser Therapy in reducing joint and muscle pain in patients with acute and chronic temporomandibular dysfunction. The study was conducted on a sample of 180 patients. The sample was divided into two groups according to the time of onset of the disease: acute TMD ( 6 months). The treatment for all patients provided for the irradiation with Diode Laser Wiser Doctor Smile with tip plane wave at wavelength of 830 nm, continuous beam to 40nW diameter and radius of 6 mm. The irradiated areas were the joint area, temporal, masseter and pterygoid. The irradiation time for each zone was 60s.The protocol adopted consisted of two weekly treatment for six weeks. Pain assessment was performed using the Visual Analog Scale (VAS), in which different scores (s) depending accused of pain by the patient: s0 no pain, s1-3 mild pain, s4-6 moderate pain, s7-9 severe pain and s10 excessive pain. The pain monitoring was performed before treatment, after 15 days and after one month. The sample included 80 patients with acute TMD and 100 with chronic TMD. The sample belonging to acute TMD group before treatment, was distributed as follows: 0% in s0; 12,5% in s1-3; 31.3% in s4-6; 53.6% in s7-9 and 2.5% in s10. After 15 days the distribution was was as follows: 6.25% in s0; 47.5% in s1-3; 20% in s4-6; 26.3% in s7-9 and 0% in s10. After 30 days the sample was well distributed: 35% in s0; 45% in 1-3; 10% in s4-6; 10% in s7-9 and 0% in s10. The sample belonging to the chronic TMD group, at time zero, was as follows: 0% at s0; 48% in S1-3; 35% in s4-6; 15% in s7-9 and 2% in s10. After 15 days the distribution was: 29% in s0; 28% in S1-3; 33% in s4-6; 10% in s7-9 and 0% in s10. After 30 days the sample was well distributed: 45% in s0; 36% in S1-3; 15% in s4-6; 4% in s7-9 and 0% in s10. The Low-Level-Laser-Therapy is a valuable tool that can significantly decrease the perception of pain in patients with temporomandibular joint

  7. Laser irradiation of carbon–tungsten materials

    International Nuclear Information System (INIS)

    Marcu, A; Lungu, C P; Ursescu, D; Porosnicu, C; Grigoriu, C; Avotina, L; Kizane, G; Marin, A; Osiceanu, P; Grigorescu, C E A; Demitri, N

    2014-01-01

    Carbon–tungsten layers deposited on graphite by thermionic vacuum arc (TVA) were directly irradiated with a femtosecond terawatt laser. The morphological and structural changes produced in the irradiated area by different numbers of pulses were systematically explored, both along the spots and in their depths. Although micro-Raman and Synchrotron-x-ray diffraction investigations have shown no carbide formation, they have shown the unexpected presence of embedded nano-diamonds in the areas irradiated with high fluencies. Scanning electron microscopy images show a cumulative effect of the laser pulses on the morphology through the ablation process. The micro-Raman spatial mapping signalled an increased percentage of sp 3 carbon bonding in the areas irradiated with laser fluencies around the ablation threshold. In-depth x-ray photoelectron spectroscopy investigations suggested a weak cumulative effect on the percentage increase of the sp 2 -sp 3 transitions with the number of laser pulses just for nanometric layer thicknesses. (paper)

  8. Activity of respiratory system during laser irradiation of brain structures

    Science.gov (United States)

    Merkulova, N. A.; Sergeyeva, L. I.

    1984-06-01

    The performance of one of the principal links of the respiratory system, the respiratory center, was studied as a function of the exposure of the medulla oblongata and the sensomotor zone of the cerebral hemisphere cortex to low level laser irradiation in the red wavelength of the spectrum. Experiments were done on white rats under barbital anesthesia. Under such conditions a substantial effect was observed on the activity of the respiratory center. Laser light may display activating or inhibitory influences, in some cases the bilateral symmetry of the activity of the respiratory center is affected indicating deep changes in the integrative mechanism of the functioning of the right and left sides of the hemispheres. The laser beam effect depends on many factors: specific light properties, duration of the exposure, repetition of exposures, initial functional state of the CNS, etc.

  9. Human Tubal-Derived Mesenchymal Stromal Cells Associated with Low Level Laser Therapy Significantly Reduces Cigarette Smoke-Induced COPD in C57BL/6 mice.

    Directory of Open Access Journals (Sweden)

    Jean Pierre Schatzmann Peron

    Full Text Available Cigarette smoke-induced chronic obstructive pulmonary disease is a very debilitating disease, with a very high prevalence worldwide, which results in a expressive economic and social burden. Therefore, new therapeutic approaches to treat these patients are of unquestionable relevance. The use of mesenchymal stromal cells (MSCs is an innovative and yet accessible approach for pulmonary acute and chronic diseases, mainly due to its important immunoregulatory, anti-fibrogenic, anti-apoptotic and pro-angiogenic. Besides, the use of adjuvant therapies, whose aim is to boost or synergize with their function should be tested. Low level laser (LLL therapy is a relatively new and promising approach, with very low cost, no invasiveness and no side effects. Here, we aimed to study the effectiveness of human tube derived MSCs (htMSCs cell therapy associated with a 30mW/3J-660 nm LLL irradiation in experimental cigarette smoke-induced chronic obstructive pulmonary disease. Thus, C57BL/6 mice were exposed to cigarette smoke for 75 days (twice a day and all experiments were performed on day 76. Experimental groups receive htMSCS either intraperitoneally or intranasally and/or LLL irradiation either alone or in association. We show that co-therapy greatly reduces lung inflammation, lowering the cellular infiltrate and pro-inflammatory cytokine secretion (IL-1β, IL-6, TNF-α and KC, which were followed by decreased mucus production, collagen accumulation and tissue damage. These findings seemed to be secondary to the reduction of both NF-κB and NF-AT activation in lung tissues with a concomitant increase in IL-10. In summary, our data suggests that the concomitant use of MSCs + LLLT may be a promising therapeutic approach for lung inflammatory diseases as COPD.

  10. Comparative study between the effects of isolated manual therapy techniques and those associated with low level laser therapy on pain in patients with temporomandibular dysfunction

    Directory of Open Access Journals (Sweden)

    Juliana Cristina Frare

    2008-01-01

    Full Text Available Objective: This study sought to evaluate the pain condition in patients with temporomandibular dysfunction after applying manual therapy techniques and those associated with this low level laser therapy. Methods: The study involved 20 patients with temporomandibular dysfunction, divided randomly into two groups: G1 (n = 10, formed by 7 women and 3 men, average age 28.2 years (± 7, treated with manual therapy techniques and G2 (n = 10, formed by 8 women and 2 men, with average age 24.01 (± 6.04, treated with the combination of manual therapy techniques and low level laser therapy. The patients were treated three times a week for four consecutive weeks. The memorandum of manual therapy techniques based on Chaintow,Makofsky and Bienfaint was used. For low level laser therapy GaAs laser (904 nm, 6 J/cm2, 0.38 mW/cm2 was used, applied at 4pre-auricular points. To analyze the pain level, the visual analog pain scale was used. For data analysis the Student’s-t and Wilcoxon tests were used, both with significance level of 5% (p <0.05.Results: There was significant reduction (p <0.05 in the level of pain in both groups treated, but in G2 the significance was higher.Conclusion: Manual therapy techniques, either alone or associated with low level laser therapy showed satisfactory results for pain control in patients with temporomandibular dysfunction.

  11. Two-year follow-up of low-level laser therapy for elderly with painful adhesive capsulitis of the shoulder

    Directory of Open Access Journals (Sweden)

    Ip D

    2015-05-01

    Full Text Available David Ip, Nga-Yue Fu Asia Medical Pain Centre, Mong Kok, Hong Kong, People's Republic of China Introduction: This paper reports on the medium-term mean 2-year prospective follow-up of a patient cohort of 35 unselected elderly patients with mean age of 65 years who visited our tertiary referral pain center for painful adhesive capsulitis of the shoulder managed with low-level laser therapy (LLLT. Materials and methods: All patients in this prospective cohort study had documentation of the diagnosis by contrast-enhanced magnetic resonance imaging before study entry and all had failed to respond to a combination of conventional physical therapy and nonsteroidal anti-inflammatory medications for not fewer than 4 weeks. LLLT, at a wavelength of 810 nm emitted from a GaAIAs semiconductor laser device with 5.4 J per point and a power density of 20 mW/cm2, was employed to irradiate six predetermined anatomic points and two acupuncture points. The treatment regimen consisted of three sessions of treatment per week for 8 consecutive weeks. Each treatment session lasted 180 seconds. Serial clinical assessment was undertaken using the Constant–Murley shoulder score. Results: A total of 50 painful shoulder joints were treated, as a number of elderly presented with bilateral symptoms. All but four painful shoulders showed significant improvement in Constant–Murley shoulder score at the end of 8-weeks’ LLLT treatment and, surprisingly, the improvement was found maintained at follow-up assessments at 1 year and 2 years. Conclusion: We conclude that LLLT is a viable option in the conservative treatment of shoulder pain arising from adhesive capsulitis of the shoulder in the elderly, with a positive clinical result of more than 90% and with clinical efficacy both in the short-term and the medium-term. Keywords: Constant–Murley shoulder score, LLLT, shoulder pain, acupuncture point

  12. The effect of low level laser therapy on ventilator-induced lung injury in mice (Conference Presentation)

    Science.gov (United States)

    Szabari, Margit V.; Miller, Alyssa J.; Hariri, Lida P.; Hamblin, Michael R.; Musch, Guido; Stroh, Helene; Suter, Melissa J.

    2016-03-01

    Although mechanical ventilation (MV) is necessary to support gas exchange in critically ill patients, it can contribute to the development of lung injury and multiple organ dysfunction. It is known that high tidal volume (Vt) MV can cause ventilator-induced lung injury (VILI) in healthy lungs and increase the mortality of patients with Acute Respiratory Distress Syndrome. Low level laser therapy (LLLT) has demonstrated to have anti-inflammatory effects. We investigated whether LLLT could alleviate inflammation from injurious MV in mice. Adult mice were assigned to 2 groups: VILI+LLLT group (3 h of injurious MV: Vt=25-30 ml/kg, respiratory rate (RR)=50/min, positive end-expiratory pressure (PEEP)=0 cmH20, followed by 3 h of protective MV: Vt=9 ml/kg, RR=140/min, PEEP=2 cmH20) and VILI+no LLLT group. LLLT was applied during the first 30 min of the MV (810 nm LED system, 5 J/cm2, 1 cm above the chest). Respiratory impedance was measured in vivo with forced oscillation technique and lung mechanics were calculated by fitting the constant phase model. At the end of the MV, bronchoalveolar lavage (BAL) was performed and inflammatory cells counted. Lungs were removed en-bloc and fixed for histological evaluation. We hypothesize that LLLT can reduce lung injury and inflammation from VILI. This therapy could be translated into clinical practice, where it can potentially improve outcomes in patients requiring mechanical ventilation in the operating room or in the intensive care units.

  13. Preoperative low level laser therapy in dogs undergoing tibial plateau levelling osteotomy: A blinded, prospective, randomized clinical trial.

    Science.gov (United States)

    Rogatko, Cleo P; Baltzer, Wendy I; Tennant, Rachel

    2017-01-16

    To evaluate the influence of preoperative low-level laser therapy (LLLT) on therapeutic outcomes of dogs undergoing tibial plateau levelling osteotomy (TPLO). Healthy dogs undergoing TPLO were randomly assigned to receive either a single preoperative LLLT treatment (800-900 nm dual wavelength, 6 W, 3.5 J/cm 2 , 100 cm 2 area) or a sham treatment. Lameness assessment and response to manipulation, as well as force plate analysis, were performed preoperatively, then again at 24 hours, two weeks, and eight weeks postoperatively. Radiographic signs of healing of the osteo-tomy were assessed at eight weeks postoperatively. Twenty-seven dogs (27 stifles) were included and no major complications occurred. At eight weeks postoperatively, a significant difference in peak vertical force analysis was noted between the LLLT (39.6% ± 4.7%) and sham groups (28.9% ± 2.6%), (p dogs in the LLLT group (6.6 ± 1.6 years) was greater than that for the sham group (4.5 ± 2.0, p dogs (5/8) had healed at the eight-week time point than in the sham group (3/12) despite the age difference (p = 0.11) Clinical significance: The results of this study demonstrate that improved peak vertical force could be related to the preoperative use of LLLT for dogs undergoing TPLO at eight weeks postoperatively. The use of LLLT may improve postoperative return to function following canine osteotomies and its use is recommended.

  14. Influence of low-level laser therapy on the healing of human bone maxillofacial defects: A systematic review.

    Science.gov (United States)

    Santinoni, Carolina Dos Santos; Oliveira, Hiskell Francine Fernandes; Batista, Victor Eduardo de Souza; Lemos, Cleidiel Aparecido Araujo; Verri, Fellippo Ramos

    2017-04-01

    This systematic review evaluates the effectiveness of low-level laser therapy (LLLT) to enhance maxillofacial area bone repair. A comprehensive search of studies published up to February 2017 and listed in PubMed/MEDLINE, Scopus, and Cochrane Library databases was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The 15 selected studies evaluated a total of 374 patients (mean age, 28.5years) who were treated with LLLT. Gallium-arsenide (GaAs) and gallium aluminium arsenide (GaAlAs) were the most commonly used devices, and LLLT parameters varied greatly. Wavelengths varied from 500 to 1000nm. Tooth extraction, distraction osteogenesis, maxillary expansion, periodontal defects, orthodontic movement and maxillary cystic defects were evaluated. From the 15 selected studies, six evaluated bone repair (primary outcomes). Of these, four studies showed improvement in bone formation after using LLLT, two demonstrated improved results for only one follow up period, and one showed no additional benefits. The other 9 studies evaluated secondary parameters related to healing (secondary outcomes) in the maxillofacial area after applying LLLT, including anti-inflammatory, analgesic, and healing accelerator effects, and quality of life related to oral health. There were no adverse or negative effects of LLLT reported. Within the limitation of this review, a possible improvement in bone density can be found when LLLT is applied postoperatively in maxillofacial bony defects. LLLT also seems to promote anti-inflammatory and analgesic effects and accelerate healing, as well as enhance quality of life related to oral health. However, LLLT use protocols need to be standardized before more specific conclusions can be drawn about this subject. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Application of low-level laser radiation with TiO2, Ag/TiO2 and S/TiO2 on Streptococcus salivarius isolated from the oral cavity

    Directory of Open Access Journals (Sweden)

    Panas Marta

    2014-09-01

    Full Text Available In our research, we determine the effect of low-level laser irradiation with nanoparticles on Streptococcus salivarius. Photodynamic killing of periodontopathogenic bacteria may be an alternative to the systemic application of antibacterial drugs used in the treatment of periodontal diseases. The application of photosensitizing nanoparticles and their excitation by visible light of blue spectra enables effective killing of periodontopathogens. This data combined with the results demonstrates that TiO2, AgTiO2 and S/TiO2 can inhibit the proliferation of Streptococcus salivarius due to its high photocatalytic activity, which irreversibly damages the cell walls and membranes.

  16. Placebo-controlled randomized clinical trial of the effect two different low-level laser therapies (LLLT)--intraoral and extraoral--on trismus and facial swelling following surgical extraction of the lower third molar.

    Science.gov (United States)

    Aras, Mutan Hamdi; Güngörmüş, Metin

    2010-09-01

    The purpose of this study is to compare the effects of extraoral and intraoral low-level laser therapies (LLLT) on postoperative trismus and oedema following the removal of mandibular third molars. Forty-eight patients who were to undergo surgical removal of their lower third molars were studied. Patients were randomly allocated to one of three groups: extraoral LLLT, intraoral LLLT, or placebo. In the study, a Ga-Al-As diode laser device with a continuous wavelength of 808 nm was used, and the laser therapy was applied by using a 1 x 3-cm handpiece. The flat-top laser beam profile was used in this therapy. For both of the LLLT groups, laser energy was applied at 100 mW (0.1 W) for a total of 120 s (0.1 W x 120 s = 12 J). Patients in the extraoral-LLLT group (n = 16) received 12-J (4 J/cm(2)) low-level laser irradiation, and the laser was applied at the insertion point of the masseter muscle immediately after the operation. Patients in the intraoral-LLLT group (n = 16) received 12-J (4 J/cm(2)) low-level laser irradiation intraorally at the operation site 1 cm from the target tissue. In the placebo group (n = 16), the handpiece was inserted intraorally at the operation site and then was touched extraorally to the masseter muscle for 1 min at each site (120 s total), but the laser was not activated. The size of the interincisal opening and facial swelling were evaluated on the second and seventh postoperative days. At the second postoperative day, trismus (29.0 +/- 7.6 mm [p = 0.010]) and swelling (105.3 +/- 5.0 mm [p = 0.047]) in the extraoral-LLLT group were significantly less than in the placebo group (trismus: 21.1 +/- 7.6 mm, swelling: 109.1 +/- 4.4 mm). Trismus (39.6 +/- 9.0 mm [p = 0.002]) in the extraoral-LLLT group at the seventh postoperative day was also significantly less than in the placebo group (29.0 +/- 6.2 mm). However, at the seventh postoperative day in the intraoral-LLLT group, only trismus (35.6 +/- 8.5 [p = 0.002]) was significantly less than

  17. Concentration of Proteins and Protein Fractions in Blood Plasma of Chickens Hatched from Eggs Irradiated with Low Level Gamma Rays

    International Nuclear Information System (INIS)

    Kraljevic, P.; Vilic, M.; Simpraga, M.; Matisic, D.; Miljanic, S.

    2011-01-01

    In literature there are many results which have shown that low dose radiation can stimulate many physiological processes of living organism. In our earlier paper it was shown that low dose of gamma radiation has a stimulative effect upon metabolic process in chickens hatched from eggs irradiated before incubation. This was proved by increase of body weight gain and body weight, as well as by increase of two enzymes activities in blood plasma (aspartate aminotransferase and alanine aminotransferase) which play an important role in protein metabolism. Therefore, an attempt was made to determine the effect of eggs irradiation by low dose gamma rays upon concentration of total proteins and protein fractions in the blood plasma of chickens hatched from irradiated eggs. The eggs of heavy breed chickens were irradiated with a dose of 0.15 Gy gamma radiation (60Co) before incubation. Along with the chickens which were hatched from irradiated eggs, there was a control group of chickens hatched from nonirradiated eggs. All other conditions were the same for both groups of chickens. Blood samples were taken from the right jugular vein on the 1 s t and 3 r d day, or from the wing vein on days 5 and 7 after hatching. The total proteins concentration in the blood plasma was determined by the biuret method using Boehringer Mannheim GmbH optimized kits. The protein fractions (albumin, α 1 -globulin, α 2 -globulin, β- and γ-globulins) were estimated electrophoretically on Cellogel strips. The total proteins concentration was significantly decreased in blood plasma of chickens hatched from irradiated eggs on days 3 (P t h day (P 2 -globulin was decreased on days 1 (P t h day of life. Obtained results indicate that low dose of gamma radiation has mostly inhibitory effect upon concentration of total proteins and protein fractions in the blood plasma of chickens hatched from irradiated eggs before incubation. (author)

  18. Analgesic effects of preinjection low-level laser/light therapy (LLLT) before third molar surgery: a double-blind randomized controlled trial

    NARCIS (Netherlands)

    Tuk, Jacco G. C.; van Wijk, Arjen J.; Mertens, Ine C.; Keleş, Zühal; Lindeboom, Jérôme A. H.; Milstein, Dan M. J.

    2017-01-01

    The aim of this study was to evaluate the analgesic effects of low-level laser therapy (LLLT) on preinjection sites in patients scheduled for third molar removal. This double-blind randomized controlled trial included 163 healthy patients undergoing third molar extractions. The study participants

  19. Could the biological robustness of low level laser therapy (Photobiomodulation) impact its use in the management of mucositis in head and neck cancer patients

    NARCIS (Netherlands)

    Sonis, Stephen T.; Hashemi, Sepehr; Epstein, Joel B.; Nair, Raj G.; Raber-Durlacher, Judith E.

    2016-01-01

    Low level laser therapy (LLLT) has been noted to be effective in mitigating the development of oral mucositis among patients being treated with chemoradiation for cancers of the head and neck. To explain the biological basis for this observation we performed a comprehensive literature search. Our

  20. Low-level laser therapy/photobiomodulation in the management of side effects of chemoradiation therapy in head and neck cancer: part 2 : proposed applications and treatment protocols

    NARCIS (Netherlands)

    Zecha, J.A.E.M.; Raber-Durlacher, J.E.; Nair, R.G.; Epstein, J.B.; Elad, S.; Hamblin, M.R.; Barasch, A.; Migliorati, C.A.; Milstein, D.M.J.; Genot, M.T.; Lansaat, L.; van der Brink, R.; Arnabat-Dominguez, J.; van der Molen, L.; Jacobi, I.; van Diessen, J.; de Lange, J.; Smeele, L.E.; Schubert, M.M.; Bensadoun, R.J.

    2016-01-01

    Purpose There is a large body of evidence supporting the efficacy of low-level laser therapy (LLLT), more recently termed photobiomodulation (PBM) for the management of oral mucositis (OM) in patients undergoing radiotherapy for head and neck cancer (HNC). Recent advances in PBM technology, together

  1. Low-level laser therapy/photobiomodulation in the management of side effects of chemoradiation therapy in head and neck cancer: part 2: proposed applications and treatment protocols

    NARCIS (Netherlands)

    Zecha, Judith A. E. M.; Raber-Durlacher, Judith E.; Nair, Raj G.; Epstein, Joel B.; Elad, Sharon; Hamblin, Michael R.; Barasch, Andrei; Migliorati, Cesar A.; Milstein, Dan M. J.; Genot, Marie-Thérèse; Lansaat, Liset; van der Brink, Ron; Arnabat-Dominguez, Josep; van der Molen, Lisette; Jacobi, Irene; van Diessen, Judi; de Lange, Jan; Smeele, Ludi E.; Schubert, Mark M.; Bensadoun, René-Jean

    2016-01-01

    There is a large body of evidence supporting the efficacy of low-level laser therapy (LLLT), more recently termed photobiomodulation (PBM) for the management of oral mucositis (OM) in patients undergoing radiotherapy for head and neck cancer (HNC). Recent advances in PBM technology, together with a

  2. Wound healing in cell studies and animal model experiments by low level laser therapy; Were clinical studies justified? A systematic review

    NARCIS (Netherlands)

    Lucas, C.; Criens-Poublon, L. J.; Cockrell, C. T.; de Haan, R. J.

    2002-01-01

    Based on results of cell studies and animal experiments, clinical trials with Low Level Laser Therapy (LLLT) were performed, which finally did not demonstrate a beneficial effect on outcome of wound healing. The aim of this study was to investigate whether the evidence from cell studies and animal

  3. Effectiveness of low-level laser therapy for patients with carpal tunnel syndrome: design of a randomized single-blinded controlled trial

    Directory of Open Access Journals (Sweden)

    Barbosa Rafael Inácio

    2012-12-01

    Full Text Available Abstract Background Carpal tunnel syndrome is the most common neuropathy in the upper extremity, resulting from the compression of the median nerve at wrist level. Clinical studies are essentials to present evidence on therapeutic resources use at early restoration on peripheral nerve functionality. Low-level laser therapy has been widely investigated in researches related to nerve regeneration. Therefore, it is suggested that the effect of low-level laser therapy associated with other conservative rehabilitation techniques may positively affect symptoms and overall hand function in compressive neuropathies such as carpal tunnel syndrome. The aim of this study is to evaluate the effectiveness of low-level laser therapy in addition to orthoses therapy and home orientations in patients with carpal tunnel syndrome. Methods/Design Patients older than 18 years old will be included, with clinical diagnosis of carpal tunnel syndrome, excluding comorbidies. A physiotherapist will conduct intervention, with a blinding evaluator. Randomization will be applied to allocate the patients in each group: with association or not to low-level laser therapy. All of them will be submitted to orthoses therapy and home orientations. Outcome will be assessed through: pain visual analogic scale, Semmes Weinstein monofilaments™ threshold sensibility test, Pinch Gauge™, Boston Carpal Tunnel Questionnaire and two point discrimination test. Discussion This paper describes the design of a randomized controlled trial, which aim to assess the effectiveness of conservative treatment added to low-level laser therapy for patients with carpal tunnel syndrome. Trial registration Brazilian Clinical Trials Registry (ReBec - 75ddtf / Universal Trial Number: U1111-1121-5184

  4. The study of low level laser irradiation therapy on brain infarction with SPECT

    Institute of Scientific and Technical Information of China (English)

    Xiao Xuechang; Jia Shaowei; Zleng Xiyuan

    2000-01-01

    Objective: Effect of rCBF and brain function on ILIB treating brain infarction will be investigated by SPECT brain perfusion imaging. Method: 3 1 patients with brain infarction, 17 patients were treated by ILIB on standard pharmaceutial treatment. SPECT brain perfusion imaging was performed before and after ILIB therapy with comparison of oneself. They were quantified with BFCR% model effect during ILIB in 14 patients were observed. Result: ILIB 30 rnme SPECT showed the improvement of rCBF and cerebral function in 14 patients with brain infarction, and in 17 patients locus were prominence than mirror regions att er ILIB therapy, both are higher singnitficant difference ( t=4.4052, P<0.0001 ), but mirror regions were not singnificant difference before and after ILIB (t=1.6995, P>0.05). BFCR% quantitative results of locus were higher mirror regions, and higher singnificant difference (t=4.5278 p<0.0001 )。 Conclusion: ILIB can improve the rCBF and cerebral function of patients with brain infarction, and provoke function of brain cells. Some new evidence was provided for ILIB treatment of cerebral ischemia

  5. Efficiencies of Low-Level Laser Therapy (LLLT) and Gabapentin in the Management of Peripheral Neuropathy: Diabetic Neuropathy.

    Science.gov (United States)

    Abdel-Wahhab, Khaled G; Daoud, Eitedal M; El Gendy, Aliaa; Mourad, Hagar H; Mannaa, Fathia A; Saber, Maha M

    2018-03-12

    Diabetic neuropathy (DN) is the highly occurred complication of diabetes mellitus; it has been defined as an event of peripheral nerve dysfunction characterized by pain, allodynia, hyperalgesia, and paraesthesia. The current study was conducted to evaluate the efficacy of low-level laser therapy (LLLT) in the management of neuropathy in diabetic rats. The used animals were divided into the following groups: negative control, streptozotocin-induced diabetic rats, and diabetic rats with peripheral neuropathy (DNP) and DNP treated with gabapentin or with LLLT. Behavioral tests were carried out through hotplate test for the determination of pain sensations and the Morris water maze test for spatial reference memory evaluation. Blood samples were collected at the end of treatment for biochemical determinations. In the current study, the latency of hind-paw lick decreased significantly when DNP are treated with gabapentin or LLLT. The Morris water maze test showed that LLLT treatment improved memory that deteriorated in DNP more than gabapentin do. The results of the biochemical study revealed that LLLT could not affect the level of beta-endorphin that decreased in DNP but significantly decreased S100B that rose in DNP. PGE2 and cytokines IL-1β, IL-10, and TNF-α showed significant increase in DNP compared with control group. The gabapentin administration or LLLT application significantly reversed the levels of the mentioned markers towards the normal values of the controls. Levels of serum MDA and nitric oxide increased significantly in the DNP but rGSH showed significant decrease. These markers were improved significantly when the DNP were treated with gabapentin or LLLT. The treatment with gabapentin or LLLT significantly decreased the raised level in total cholesterol in DNP but could not decrease the elevated level of triglycerides, while LDL cholesterol decreased significantly in DNP treated with gabapentin but not affected by LLLT. Values of serum alanine

  6. Low levels of glutathione are sufficient for survival of keratinocytes after UV irradiation and for healing of mouse skin wounds.

    Science.gov (United States)

    Telorack, Michèle; Abplanalp, Jeannette; Werner, Sabine

    2016-08-01

    Reduced levels of the cellular antioxidant glutathione are associated with premature skin aging, cancer and impaired wound healing, but the in vivo functions of glutathione in the skin remain largely unknown. Therefore, we analyzed mice lacking the modifier subunit of the glutamate cysteine ligase (Gclm), the enzyme that catalyzes the rate-limiting step of glutathione biosynthesis. Glutathione levels in the skin of these mice were reduced by 70 %. However, neither skin development and homeostasis, nor UVA- or UVB-induced apoptosis in the epidermis were affected. Histomorphometric analysis of excisional wounds did not reveal wound healing abnormalities in young Gclm-deficient mice, while the area of hyperproliferative epithelium as well as keratinocyte proliferation were affected in aged mice. These findings suggest that low levels of glutathione are sufficient for wound repair in young mice, but become rate-limiting upon aging.

  7. A follow-up study on radiation effect of low-level γ-irradiation on 45 persons

    International Nuclear Information System (INIS)

    Xu Xiufeng; Wang Yongxiao; Fang Yongxin

    1985-01-01

    Forty-five males once exposed to γ-irradiation were observed clinically and by biological method from 1966 to 1981. The doses ranged form 0.10 to 0.468 Gy. Neurasthenic syndromes were observed in all cases. Thirty cases of lens opacities were observed by slit lamp microscopy. There were one case of spontaneous abortion, one neonatal death, one strabismus and one mental retardation among 37 children born to the irradiated subjects. There was one case whose wife failed to conceive since she married for 4 years. Analysis of chromosome aberrations and scoring of micro-nuclei in peripheral blood lymphocytes were statistically higher (P < 0.01) than that of controls, but withot linear relationships between doses and effects. The levels of serum immunoglobulin and serum follicular stimulating hormone were within normal limits. No cancer, or leukemia were detected by clinical examinations

  8. The Lack of Cytotoxic Effect and Radioadaptive Response in Splenocytes of Mice Exposed to Low Level Internal β-Particle Irradiation through Tritiated Drinking Water in Vivo

    Directory of Open Access Journals (Sweden)

    Matthew Flegal

    2013-12-01

    Full Text Available Health effects of tritium, a β-emitter and a by-product of the nuclear industry, is a subject of significant controversy. This mouse in vivo study was undertaken to monitor biological effects of low level tritium exposure. Mice were exposed to tritiated drinking water (HTO at 10 KBq/L, 1 MBq/L and 20 MBq/L concentrations for one month. The treatment did not result in a significant increase of apoptosis in splenocytes. To examine if this low level tritium exposure alters radiosensitivity, the extracted splenocytes were challenged in vitro with 2 Gy γ-radiation, and apoptotic responses at 1 and 24 h were measured. No alterations in the radiosensitivity were detected in cells from mice exposed to tritium compared to sham-treated mice. In contrast, low dose γ-irradiation at 20 or 100 mGy, resulted in a significant increase in resistance to apoptotic cell death after 2 Gy irradiation; an indication of the radioadaptive response. Overall, our data suggest that low concentrations of tritium given to mice as HTO in drinking water do not exert cytotoxic effect in splenocytes, nor do they change cellular sensitivity to additional high dose γ-radiation. The latter may be considered as the lack of a radioadaptive response, typically observed after low dose γ-irradiation.

  9. Effect of low-level laser therapy on the healing process of donor site in patients with grade 3 burn ulcer after skin graft surgery (a randomized clinical trial).

    Science.gov (United States)

    Vaghardoost, Reza; Momeni, Mahnoush; Kazemikhoo, Nooshafarin; Mokmeli, Soheila; Dahmardehei, Mostafa; Ansari, Fereshteh; Nilforoushzadeh, Mohammad Ali; Sabr Joo, Parisa; Mey Abadi, Sara; Naderi Gharagheshlagh, Soheila; Sassani, Saeed

    2018-04-01

    Skin graft is a standard therapeutic technique in patients with deep ulcers, but managing donor site after grafting is very important. Although several modern dressings are available to enhance the comfort of donor site, using techniques that accelerate wound healing may enhance patient satisfaction. Low-level laser therapy (LLLT) has been used in several medical fields, including healing of diabetic, surgical, and pressure ulcers, but there is not any report of using this method for healing of donor site in burn patients. The protocols and informed consent were reviewed according to Medical Ethics Board of Shahid Beheshti University of Medical Sciences (IR.SBMU.REC.1394.363) and Iranian Registry of Clinical Trials (IRCT2016020226069N2). Eighteen donor sites in 11 patients with grade 3 burn ulcer were selected. Donor areas were divided into 2 parts, for laser irradiation and control randomly. Laser area was irradiated by a red, 655-nm laser light, 150 mW, 2 J/cm 2 , on days 0 (immediately after surgery), 3, 5, and 7. Dressing and other therapeutic care for both sites were the same. The patients and the person who analyzed the results were blinded. The size of donor site reduced in both groups during the 7-day study period (P < 0.01) and this reduction was significantly greater in the laser group (P = 0.01). In the present study, for the first time, we evaluate the effects of LLLT on the healing process of donor site in burn patients. The results showed that local irradiation of red laser accelerates wound healing process significantly.

  10. Argon laser irradiation of the otolithic organ

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, T.; Nomura, Y.; Young, Y.H.; Hara, M. (Univ. of Tokyo (Japan))

    1990-12-01

    An argon laser was used to irradiate the otolithic organs of guinea pigs and cynomolgus monkeys. After stapedectomy, the argon laser (1.5 W x 0.5 sec/shot) irradiated the utricle or saccule without touching the sensory organs. The stapes was replaced over the oval window after irradiation. The animals used for acute observation were killed immediately for morphologic studies; those used for long-term observation were kept alive for 2, 4, or 10 weeks. Acute observation revealed that sensory and supporting cells were elevated from the basement membrane only in the irradiated area. No rupture of the membranous labyrinth was observed. Long-term observation revealed that the otolith of the macula utriculi had disappeared in 2-week specimens. The entire macula utricili had disappeared in 10-week specimens. No morphologic changes were observed in cochlea, semicircular canals, or membranous labyrinth. The saccule showed similar changes.

  11. Application of Laser Irradiation for Restorative Treatments

    OpenAIRE

    Davoudi, Amin; Sanei, Maryam; Badrian, Hamid

    2016-01-01

    Nowadays, lasers are widely used in many fields of medicine. Also, they can be applied at many branches of dental practice such as diagnosis, preventive procedures, restorative treatments, and endodontic therapies. Procedures like caries removal, re-mineralization, and vital pulp therapy are the most noticeable effects of laser irradiation which has gained much attention among clinicians. With controlled and appropriate wavelength, they can help stimulating dentinogenesis, controlling pulpal ...

  12. Effects of low-level prenatal γ-ray irradiation on postnatal growth and behavior in mice

    International Nuclear Information System (INIS)

    Wang Bing; Zhou Xiangyan

    1994-01-01

    Pregnant adult C57BL/6J mice were randomly allotted to six experimental groups. Doses of 0, 0.106, 0.156, 0.312, 0.518 or 0.656 Gy from 60 Co γ-rays were delivered respectively on the 12.5th day of gestation by single radiation except for group 1 (used as control). Pups were observed for the growth (body weight, BW), the age of acquisition of three reflexes (surface righting, SR, negative geotaxis, NG and grasp reflex, GR), the appearance of three physiologic markers (eye opening, EO, pinna detachment, PD and incisor eruption, IE) and the sensuous functions (visual placing, VP and mother-taxis, MT). And by using these parameters 0.156 to 0.312 Gy irradiation may represent a threshold range for exposure on the 12.5th day of gestation to a single γ-radiation

  13. Effects of low level prenatal beta-irradiation of tritiated water on postnatal behavior, learning and memory ability in mice

    International Nuclear Information System (INIS)

    Wang Bing; Zhou Xiangyan

    1993-01-01

    Pregnant adult C57 BL/6J strain mice, randomly assigned to 1 of 4 experimental groups, were irradiated with exponentially decreasing doses of tritium beta-rays but group 1 (used as a control) by single injection of tritiated water (HTO) at their 12.5 th day of gestation. Offsprings of male, received accumulative doses of 0, 0.5, 1.10 or 0.30 Gy in uterus were trained or examined on learning and memory ability or with behavioral tests. Significant dose-response relationships for alternations in those test were found due to exposure to 0.10 Gy or above. These results indicate that exposure to HTO during the fetal period in mice results in dose-dependent alteration in postnatal behavior, learning and memory ability. 0.05-0.10 Gy exposure may represent a threshold for the experimental conditions of this research using these parameters

  14. A systematic review with procedural assessments and meta-analysis of low level laser therapy in lateral elbow tendinopathy (tennis elbow).

    Science.gov (United States)

    Bjordal, Jan M; Lopes-Martins, Rodrigo Ab; Joensen, Jon; Couppe, Christian; Ljunggren, Anne E; Stergioulas, Apostolos; Johnson, Mark I

    2008-05-29

    Recent reviews have indicated that low level level laser therapy (LLLT) is ineffective in lateral elbow tendinopathy (LET) without assessing validity of treatment procedures and doses or the influence of prior steroid injections. Systematic review with meta-analysis, with primary outcome measures of pain relief and/or global improvement and subgroup analyses of methodological quality, wavelengths and treatment procedures. 18 randomised placebo-controlled trials (RCTs) were identified with 13 RCTs (730 patients) meeting the criteria for meta-analysis. 12 RCTs satisfied half or more of the methodological criteria. Publication bias was detected by Egger's graphical test, which showed a negative direction of bias. Ten of the trials included patients with poor prognosis caused by failed steroid injections or other treatment failures, or long symptom duration or severe baseline pain. The weighted mean difference (WMD) for pain relief was 10.2 mm [95% CI: 3.0 to 17.5] and the RR for global improvement was 1.36 [1.16 to 1.60]. Trials which targeted acupuncture points reported negative results, as did trials with wavelengths 820, 830 and 1064 nm. In a subgroup of five trials with 904 nm lasers and one trial with 632 nm wavelength where the lateral elbow tendon insertions were directly irradiated, WMD for pain relief was 17.2 mm [95% CI: 8.5 to 25.9] and 14.0 mm [95% CI: 7.4 to 20.6] respectively, while RR for global pain improvement was only reported for 904 nm at 1.53 [95% CI: 1.28 to 1.83]. LLLT doses in this subgroup ranged between 0.5 and 7.2 Joules. Secondary outcome measures of painfree grip strength, pain pressure threshold, sick leave and follow-up data from 3 to 8 weeks after the end of treatment, showed consistently significant results in favour of the same LLLT subgroup (p elbow tendon insertions, seem to offer short-term pain relief and less disability in LET, both alone and in conjunction with an exercise regimen. This finding contradicts the conclusions of

  15. A systematic review with procedural assessments and meta-analysis of Low Level Laser Therapy in lateral elbow tendinopathy (tennis elbow

    Directory of Open Access Journals (Sweden)

    Couppe Christian

    2008-05-01

    Full Text Available Abstract Background Recent reviews have indicated that low level level laser therapy (LLLT is ineffective in lateral elbow tendinopathy (LET without assessing validity of treatment procedures and doses or the influence of prior steroid injections. Methods Systematic review with meta-analysis, with primary outcome measures of pain relief and/or global improvement and subgroup analyses of methodological quality, wavelengths and treatment procedures. Results 18 randomised placebo-controlled trials (RCTs were identified with 13 RCTs (730 patients meeting the criteria for meta-analysis. 12 RCTs satisfied half or more of the methodological criteria. Publication bias was detected by Egger's graphical test, which showed a negative direction of bias. Ten of the trials included patients with poor prognosis caused by failed steroid injections or other treatment failures, or long symptom duration or severe baseline pain. The weighted mean difference (WMD for pain relief was 10.2 mm [95% CI: 3.0 to 17.5] and the RR for global improvement was 1.36 [1.16 to 1.60]. Trials which targeted acupuncture points reported negative results, as did trials with wavelengths 820, 830 and 1064 nm. In a subgroup of five trials with 904 nm lasers and one trial with 632 nm wavelength where the lateral elbow tendon insertions were directly irradiated, WMD for pain relief was 17.2 mm [95% CI: 8.5 to 25.9] and 14.0 mm [95% CI: 7.4 to 20.6] respectively, while RR for global pain improvement was only reported for 904 nm at 1.53 [95% CI: 1.28 to 1.83]. LLLT doses in this subgroup ranged between 0.5 and 7.2 Joules. Secondary outcome measures of painfree grip strength, pain pressure threshold, sick leave and follow-up data from 3 to 8 weeks after the end of treatment, showed consistently significant results in favour of the same LLLT subgroup (p Conclusion LLLT administered with optimal doses of 904 nm and possibly 632 nm wavelengths directly to the lateral elbow tendon insertions

  16. Low-level laser therapy/photobiomodulation in the management of side effects of chemoradiation therapy in head and neck cancer: part 2: proposed applications and treatment protocols

    Science.gov (United States)

    Zecha, Judith A. E. M.; Raber-Durlacher, Judith E.; Nair, Raj G.; Epstein, Joel B.; Elad, Sharon; Hamblin, Michael R.; Barasch, Andrei; Migliorati, Cesar A.; Milstein, Dan M. J.; Genot, Marie-Thérèse; Lansaat, Liset; van der Brink, Ron; Arnabat-Dominguez, Josep; van der Molen, Lisette; Jacobi, Irene; van Diessen, Judi; de Lange, Jan; Smeele, Ludi E.; Schubert, Mark M.

    2016-01-01

    Purpose There is a large body of evidence supporting the efficacy of low-level laser therapy (LLLT), more recently termed photobiomodulation (PBM) for the management of oral mucositis (OM) in patients undergoing radiotherapy for head and neck cancer (HNC). Recent advances in PBM technology, together with a better understanding of mechanisms involved and dosimetric parameters may lead to the management of a broader range of complications associated with HNC treatment. This could enhance patient adherence to cancer therapy, and improve quality of life and treatment outcomes. The mechanisms of action, dosimetric, and safety considerations for PBM have been reviewed in part 1. Part 2 discusses the head and neck treatment side effects for which PBM may prove to be effective. In addition, PBM parameters for each of these complications are suggested and future research directions are discussed. Methods Narrative review and presentation of PBM parameters are based on current evidence and expert opinion. Results PBM may have potential applications in the management of a broad range of side effects of (chemo)radiation therapy (CRT) in patients being treated for HNC. For OM management, optimal PBM parameters identified were as follows: wavelength, typically between 633 and 685 nm or 780–830 nm; energy density, laser or light-emitting diode (LED) output between 10 and 150 mW; dose, 2–3 J (J/cm2), and no more than 6 J/cm2 on the tissue surface treated; treatment schedule, two to three times a week up to daily; emission type, pulsed (<100 Hz); and route of delivery, intraorally and/or transcutaneously. To facilitate further studies, we propose potentially effective PBM parameters for prophylactic and therapeutic use in supportive care for dermatitis, dysphagia, dry mouth, dysgeusia, trismus, necrosis, lymphedema, and voice/speech alterations. Conclusion PBM may have a role in supportive care for a broad range of complications associated with the treatment of HNC with CRT

  17. Radiological (MRI and Biochemical effects of Low Level LASER therapy in chronic Osteo arthritis in Al-Kharj, Saudi Arabia: A Randomized Control Trial

    Directory of Open Access Journals (Sweden)

    Gopal Nambi S

    2016-11-01

    Full Text Available Osteoarthritis is one of the degenerative diseases and Low level laser therapy (LLLT has been prescribed as nonoperative treatment in physiotherapy. But the available evidences of finding the radiological and biochemical effectiveness of LLLT are very few. So, the purpose of this study is to find the radiological and biochemical effect of Low level laser therapy (LLLT in the treatment of Osteoarthritis. 34 subjects who fulfilled the inclusion and exclusion criteria were divided into two groups (Active Laser group – ALG & Placebo Laser group - PLG with randomized sampling method. ALG was treated with active laser head, whereas PLG treated same like ALG but without emission of energy. Both groups were applied with kinesio tape for 4 weeks. The frequency of the treatment was three times per week for 4 weeks in both groups. Subjects were assessed at baseline, 4th and 8th week. Contact area (mm2 – medial & lateral and cartilage thickness (percentage - medial & lateral was measured by Magnetic resonance image (MRI and CTX-II (μmg/mmol was measured by urine analysis. A statistically significant (p ≤0.05 difference between both groups were noted at the period of 8 week for contact area (lateral and CTX-II and insignificant (p ≥ 0.05 difference in contact area (medial and cartilage thickness (medial & lateral were noted. In conclusion, the low level laser therapy is helpful in modifying the biochemical components and leads to make changes in the cartilage which subsequently improve the quality of life of OA patients.

  18. Epidemiological surveys on the effects of low-level radiation dose: a comparative assessment. Vol. A: pre-conception irradiation effects. Vol. E (DRAFT A): group collation tables

    Energy Technology Data Exchange (ETDEWEB)

    Rose, K.S.B.

    1988-01-01

    In this report, the health effects of low-level doses of radiation are considered by reference to published epidemiological surveys. The work was carried out with three objectives in mind: 1. to provide a comprehensive and critical review of the subject; 2. to seek consistent indications of particular health effects by collating results and comparing with those from surveys at moderate-level doses; 3. to provide an authoritative view on the epidemiology of low-level radiation-induced health effects. Vol E (DRAFT A) is appended and contains group collation tables. Epidemiological surveys can be conveniently divided into four classes (A, B, C, D) according to the phase of life when irradiation occurs or the effect is diagnosed. The first of the classes (A) is addressed here; this class is concerned with possible effects arising from radiation received by a parent before conception. Possible effects of preconception irradiation were identified under four broad groupings. These are Down's syndrome, ''Indicators of Reproductive Damage'' (mainly Primary Sterility, Congenital Abnormalities, Sex Ratio, Fetal Mortality, Infant Mortality), Childhood Malignancies, and Chromosomal Changes in Abortuses. Information about each survey, and comparisons with results from moderate-level dose surveys, are contained in synopses that are set out in the Appendix.

  19. Can combined use of low-level lasers and hyaluronic acid injections prolong the longevity of degenerative knee joints?

    Directory of Open Access Journals (Sweden)

    Ip D

    2015-08-01

    Full Text Available David Ip, Nga Yue FuAsia Medical Pain Centre, Grand Plaza, Mong Kok, Hong KongBackground: This study evaluated whether half-yearly hyaluronic acid injection together with low-level laser therapy in addition to standard conventional physical therapy can successfully postpone the need for joint replacement surgery in elderly patients with bilateral symptomatic tricompartmental knee arthritis.Methods: In this prospective, double-blind, placebo-controlled study, 70 consecutive unselected elderly patients with bilateral tricompartmental knee arthritis were assigned at random to either one of two conservative treatment protocols to either one of the painful knees. Protocol A consisted of conventional physical therapy plus a sham light source plus saline injection, and protocol B consisted of protocol A with addition of half-yearly hyaluronic acid injection as well as low-level laser treatment instead of using saline and a sham light source. Treatment failure was defined as breakthrough pain necessitating joint replacement.Results: Among the 140 painful knees treated with either protocol A or protocol B, only one of the 70 painful knees treated by protocol B required joint replacement, whereas 15 of the 70 painful knees treated by protocol A needed joint replacement surgery (P<0.05.Conclusion: We conclude that half-yearly hyaluronic acid injections together with low-level laser therapy should be incorporated into the standard conservative treatment protocol for symptomatic knee arthritis, because it may prolong the longevity of the knee joint without the need for joint replacement.Keywords: knee osteoarthritis, hyaluronic acid injection, low-level laser, outcome

  20. Influence of postoperative low-level laser therapy on the osseointegration of self-tapping implants in the posterior maxilla: A 6-week split-mouth clinical study

    OpenAIRE

    Mandić Borka; Lazić Zoran; Marković Aleksa; Mandić Bojan; Mandić Miška; Đinić Ana; Miličić Biljana

    2015-01-01

    Background/Aim. Low-level laser therapy (LLLT) has been proven to stimulate bone repair, affecting cellular proliferation, differentiation and adhesion, and has shown a potential to reduce the healing time following implant placement. The aim of this clinical study was to investigate the influence of postoperative LLLT osseointegration and early success of self-tapping implants placed into low-density bone. Methods. Following the split-mouth design, self-ta...

  1. Studies concerning the effects of low level prenatal X-irradiation on postnatal growth and adult behaviour in the Wistar rat

    International Nuclear Information System (INIS)

    Jensh, R.P.; Brent, R.L.; Vogel, W.H.

    1986-01-01

    Fifty-nine pregnant Wistar strain rats were sham irradiated or given a 0.1 or 0.2 Gy exposure of X-radiation on the 9th or 17th day of gestation. Twenty-seven were killed at term for teratologic analysis. The remaining mothers raised their young. At 60 days of age the 252 offspring were randomly assigned three of six tests: open field, swimming, hanging, activity wheel, water T-maze, or conditioned avoidance response. Male offspring exposed at the 0.2 Gy level exhibited retarded growth only during the first few weeks of postnatal life. Female offspring exposed on the 17th day to 0.2 Gy X-radiation were growth retarded throughout the test period. Postnatal growth rates were not significantly different between the irradiated and control groups. There were no significant alterations in adult behaviour due to prenatal X-irradiation. There were sex differences in activity wheel and forelimb hanging performance, unrelated to radiation exposure. These results indicate that prenatal low level X-irradiation on the 9th or 17th day of gestation dose not result in significant alterations in rat adult behavioural performance but prenatal growth retardation persists postnatally. Growth may be a more sensitive indicator of the effects of prenatal exposure than postnatal behaviour. (author)

  2. Low-level laser therapy for the prevention of low salivary flow rate after radiotherapy and chemotherapy in patients with head and neck cancer

    International Nuclear Information System (INIS)

    Gonnelli, Fernanda Aurora Stabile; Palma, Luiz Felipe; Giordani, Adelmo Jose; Dias, Rodrigo Souza; Segreto, Roberto Araujo; Segreto, Helena Regina Comodo; Deboni, Aline Lima Silva

    2016-01-01

    Objective: to determine whether low-level laser therapy can prevent salivary hypofunction after radiotherapy and chemotherapy in head and neck cancer patients. Materials and methods: ee evaluated 23 head and neck cancer patients, of whom 13 received laser therapy and 10 received clinical care only. An InGaAlP laser was used intra-orally (at 660 nm and 40 mW) at a mean dose of 10.0 J/cm 2 and extra-orally (at 780 nm and 15 mW) at a mean dose of 3.7 J/cm 2 , three times per week, on alternate days. Stimulated and unstimulated sialometry tests were performed before the first radiotherapy and chemotherapy sessions (NO) and at 30 days after the end of treatment (N30). Results: At N30, the mean salivary flow rates were significantly higher among the laser therapy patients than among the patients who received clinical care only, in the stimulated and unstimulated sialometry tests (p = 0.0131 and p = 0.0143, respectively). Conclusion: low-level laser therapy, administered concomitantly with radiotherapy and chemotherapy, appears to mitigate treatment induced salivary hypofunction in patients with head and neck cancer. (author)

  3. Low-level laser therapy for the prevention of low salivary flow rate after radiotherapy and chemotherapy in patients with head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gonnelli, Fernanda Aurora Stabile [Faculdades Metropolitanas Unidas (FMU), Sao Paulo, SP (Brazil); Palma, Luiz Felipe; Giordani, Adelmo Jose; Dias, Rodrigo Souza; Segreto, Roberto Araujo; Segreto, Helena Regina Comodo [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina; Deboni, Aline Lima Silva

    2016-03-15

    Objective: to determine whether low-level laser therapy can prevent salivary hypofunction after radiotherapy and chemotherapy in head and neck cancer patients. Materials and methods: ee evaluated 23 head and neck cancer patients, of whom 13 received laser therapy and 10 received clinical care only. An InGaAlP laser was used intra-orally (at 660 nm and 40 mW) at a mean dose of 10.0 J/cm{sup 2} and extra-orally (at 780 nm and 15 mW) at a mean dose of 3.7 J/cm{sup 2} , three times per week, on alternate days. Stimulated and unstimulated sialometry tests were performed before the first radiotherapy and chemotherapy sessions (NO) and at 30 days after the end of treatment (N30). Results: At N30, the mean salivary flow rates were significantly higher among the laser therapy patients than among the patients who received clinical care only, in the stimulated and unstimulated sialometry tests (p = 0.0131 and p = 0.0143, respectively). Conclusion: low-level laser therapy, administered concomitantly with radiotherapy and chemotherapy, appears to mitigate treatment induced salivary hypofunction in patients with head and neck cancer. (author)

  4. Heat profiles of laser-irradiated nails.

    Science.gov (United States)

    Paasch, Uwe; Nenoff, Pietro; Seitz, Anna-Theresa; Wagner, Justinus A; Kendler, Michael; Simon, Jan C; Grunewald, Sonja

    2014-01-01

    Onychomycosis is a worldwide problem with no tendency for self-healing, and existing systemic treatments achieve disease-free nails in only 35 to 76% of cases. Recently, treatment of nail fungus with a near-infrared laser has been introduced. It is assumed that fungal eradication is mediated by local heat. To investigate if laser treatment has the potential to eradicate fungal hyphae and arthrospores, laser heat application and propagation needs to be studied in detail. This study aimed to measure nail temperatures using real-time videothermography during laser irradiation. Treatment was performed using 808- and 980-nm linear scanning diode lasers developed for hair removal, enabling contact-free homogeneous irradiation of a human nail plate in one pass. Average and peak temperatures increased pass by pass, while the laser beam moved along the nail plates. The achieved mean peak temperatures (808 nm: 74.1 to 112.4°C, 980 nm: 45.8 to 53.5°C), as well as the elevation of average temperatures (808 nm: 29.5 to 38.2°C, 980 nm: 27.1 to 32.6°C) were associated with pain that was equivalent to that of hair removal procedures and was not significantly different for various wavelengths. The linear scanning laser devices provide the benefits of contact-free homogeneous heating of the human nail while ensuring adequate temperature rises.

  5. Application of Laser Irradiation for Restorative Treatments.

    Science.gov (United States)

    Davoudi, Amin; Sanei, Maryam; Badrian, Hamid

    2016-01-01

    Nowadays, lasers are widely used in many fields of medicine. Also, they can be applied at many branches of dental practice such as diagnosis, preventive procedures, restorative treatments, and endodontic therapies. Procedures like caries removal, re-mineralization, and vital pulp therapy are the most noticeable effects of laser irradiation which has gained much attention among clinicians. With controlled and appropriate wavelength, they can help stimulating dentinogenesis, controlling pulpal hemorrhage, sterilization, healing of collagenic proteins, formation of a fibrous matrix, and inducing hard tissue barrier. Nevertheless, there are many controversies in literatures regarding their effects on the quality of bonded restorations. It hampered a wide application of lasers in some aspects of restorative dentistry and requirements to identify the best way to use this technology. The aim of this mini review is to explain special characteristics of laser therapy and to introduce the possible applications of laser devices for dental purposes.

  6. Efficacy of low-level laser therapy in the management of pain, facial swelling, and postoperative trismus after a lower third molar extraction. A preliminary study.

    Science.gov (United States)

    López-Ramírez, Marta; Vílchez-Pérez, Miguel Angel; Gargallo-Albiol, Jordi; Arnabat-Domínguez, Josep; Gay-Escoda, Cosme

    2012-05-01

    Pain, swelling, and trismus are the most common complications after surgical removal of impacted lower third molars. The aim of this study was to evaluate the analgesic and anti-inflammatory effects of a low-level laser therapy (Laser Smile™, Biolase®, San Clemente, USA) applied to the wound appeared after the surgical removal of impacted lower third molars. A prospective, randomized, and double-blind study was undertaken in 20 healthy patients with two symmetrically impacted lower third molars. The application of a low-level laser was made randomly on one of the two sides after surgery. The experimental side received 5 J/cm(2) of energy density, a wavelength of 810 nm, and an output power of 0.5 W. On the control side, a handpiece was applied intraorally, but the laser was not activated. Evaluations of postoperative pain, trismus, and swelling were made. The sample consisted of 11 women and nine men, and mean age was 23.35 years (18-37). The pain level in the first hours after surgery was lower in the experimental side than in the placebo side, although without statistically significant differences (p = 0.258). Swelling and trismus at the 2nd and 7th postoperative days were slightly higher in the control side, although not statistically significant differences were detected (p > 0.05). The application of a low-level laser with the parameters used in this study did not show beneficial affects in reducing pain, swelling, and trismus after removal of impacted lower third molars.

  7. Laser de baixa intensidade em deiscência aguda de safenectomia: proposta terapêutica Low level laser therapy in acute dehiscence saphenectomy: therapeutic proposal

    Directory of Open Access Journals (Sweden)

    Nathali Cordeiro Pinto

    2009-03-01

    Full Text Available Deiscência é uma complicação temida em cirurgias de grande porte. Paciente submetida a revascularização miocárdica evoluiu com deiscência de safenectomia em membro inferior, edema e dor no 15º dia pós-operatório (PO, tendo sido realizado inicialmente o tratamento convencional no ambulatório sem melhora clínica. No 30º PO, aplicou-se somente Laser de Baixa Intensidade (LBI ao redor da borda da ferida, pontualmente. A lesão respondeu com tecido de granulação, diminuição do processo inflamatório e analgesia desde a primeira aplicação. Neste estudo piloto, a laserterapia mostrou ter um papel importante como agente facilitador de cicatrização, por meio de uma terapia nãoinvasiva, eficaz e segura.Dehiscence is a feared complication after major surgeries. Patient who had undergone coronary artery bypass grafting developed saphenectomy's dehiscence on lower limb with edema and pain on the 15th postoperative day. Conventional treatment had been initially performed without clinical improvement. On the 30th postoperative day only Low Level Laser Therapy (LLLT was applied punctually around surgical wounds edge. The results revealed granulated tissue, reduction of inflammatory process and analgesic effect since the first application. In this pilot study, LLLT has shown a considerable role as a wound healing agent, through a new proposal for efficient, safe and noninvasive therapy.

  8. Performance of Shiva as a laser fusion irradiation facility

    International Nuclear Information System (INIS)

    Speck, D.R.; Bliss, E.S.; Glaze, J.A.; Johnson, B.C.; Manes, K.R.; Ozarski, R.G.; Rupert, P.R.; Simmons, W.W.; Swift, C.D.; Thompson, C.E.

    1979-01-01

    Shiva is a 20 beam Nd:Glass Laser and Target Irradiation Facility at the Lawrence Livermore Laboratory. The laser system and integrated target facility evolved during the last year from a large, untested, experimental laser system to a target irradiation facility which has provided significant laser driven inertial confinement fusion data. The operation of the facility is discussed

  9. Análise da dose do laser de baixa potência em equipamentos nacionais Analysis of low-level laser therapy doses in Brazilian equipment

    Directory of Open Access Journals (Sweden)

    TY Fukuda

    2008-02-01

    Full Text Available CONTEXTUALIZAÇÃO: A laserterapia de baixa potência vem sendo cada vez mais utilizada, e o crescente interesse por seus efeitos relaciona-se com a grande quantidade de publicações científicas. Muitos terapeutas e pesquisadores têm-se baseado na definição da dose do laser pela densidade energética (deltaE; porém, a grande variedade de equipamentos de laser pode levar a diferença nos resultados terapêuticos encontrados, por fornecerem parâmetros que variam de acordo com o fabricante. OBJETIVO: Analisar a energia final transmitida ao tecido ao aplicar-se a mesma deltaE em equipamentos de diferentes marcas nacionais. MATERIAIS E MÉTODOS: Foram avaliados sete equipamentos nacionais, com potência média (Pm diferentes, e foram realizadas simulações aplicando deltaE de 1J/cm² em cada aparelho, para avaliar possíveis diferenças na energia final. RESULTADOS: A mesmadeltaE aplicada em diferentes aparelhos nacionais forneceu energia final que variou entre 10 e 90mJ. Esta variação na energia deveu-se principalmente a diferenças na Pm, sendo encontrados valores entre 5,4 e 75mW. CONCLUSÃO: Esta variabilidade na energia final, que é transmitida ao tecido, indica que a deltaE parece não ser o parâmetro que melhor descreve a dose a ser utilizada. É preciso mencionar não só a deltaE, mas também a energia final, para que se possa estabelecer a dose para obtenção do melhor resultado terapêutico.INTRODUCTION: Low-level laser therapy is becoming more popular and there is a growing interest in its effects, as reflected in the increased number of articles published about the subject. Many therapists and researchers have used a laser dose definition based on energy density (deltaE. However, the variety of laser equipments may lead to differences in the therapeutic results found, since the parameters supplied by these equipments vary according to the manufacturer. OBJECTIVE: To analyze the final energy transmitted to the tissue when

  10. The photo biological effect of low level laser therapy on serum level of leptin, cholesterol and triglycerides in overweight and obese females

    International Nuclear Information System (INIS)

    Salem, E.S.; Tawfik, M.S.; Youssef, S.S.; Serry, Z.M.; Aboel magd, H.F.

    2013-01-01

    The use of low level laser for body contouring and weight reduction depends on the photochemical non thermal effect of laser light on the adipose tissue. LLLT was reported to liquefy or release stored fat in adipocytes by the opening of specialized yet not identified cell membrane-associated pores after a brief treatment The concentration of leptin in adipose tissue and serum closely parallel the mass of adipose tissue and adipocyte size and triglycerides content. Thus, leptin increases in obesity and falls with weight loss. The current study was conducted to evaluate the effect of the low level laser therapy (LLLT) on leptin hormone, Cholesterol and triglyceride in both overweight and obese females. Twenty women were included in this study. Their ages ranged from 30-40 years. They were divided into two equal groups. Group A (Overweight group): included 10 females with BMI between 25 and 29.9 Kg/m2 -Group B (Obese group): included 10 females with BMI . 30. Both groups received LLL to the abdomen using laser scanner for uniform distribution of the beam above and below the umbilicus. Duration of treatment was 30 minutes, 2 times per week for 8 weeks as a total period of treatment. Serum level of leptin was estimated by radioimmunoassay (RIA). As regards serum cholesterol and triglyceride they were determined by enzymatic colorimetric test. Biochemical assessments were done before and after treatment. Results of the present study showed that in the overweight group laser treatment resulted in highly significant reduction in leptin serum level accompanied by highly significant increase in serum triglycerides level. Meanwhile, the increase in cholesterol level was insignificant. As regards the obese group, alteration in serum leptin level caused by laser treatment was not significant. In this group the increase in triglycerides and cholesterol serum levels after treatment were highly significant

  11. 50: EFFECT OF LOW-LEVEL LASER THERAPY IN THE TREATMENT OF BURNING MOUTH SYNDROME: A SYSTEMATIC REVIEW AND META-ANALYSIS

    Science.gov (United States)

    Amirzade-Iranaq, Mohammad Hossein; Masoumil, S. M. R.

    2017-01-01

    Background and aims low level laser therapy (LLLT) has been used in the treatment of burning mouth syndrome (BMS) for recent years and the role of intervention has not proven accurately. We conducted a systematic review and meta-analysis to investigate the efficacy of low level laser therapy (LLLT) in the treatment of burning mouth syndrome (BMS). Methods We performed a search on PubMed, Embase, Scopus and Web of Science for relevant studies that met our eligibility criteria. English language restriction included and only randomized clinical trials on humans entered to this study. Data extraction: 63 Records identified through database searching and also 1 Additional records identified by hand-searching. After removing duplicates and studies not meeting inclusion criteria like case reports and animal studies, at last 9 Full-text articles assessed for eligibility. Quality assessment of this study was executed by using the Critical Appraisal Skills Programme (CASP). Eventually 7 of these studies were selected for meta-analysis by Comprehensive meta-analysis version 2. Results From Total of 9 studies 7 randomized controlled trials (RCTs) studies including BMS patients were selected. Our results shows us LLLT can relieve the sensation of mouth. WMD in visual analog scale (VAS) pain outcome score after treatment was significantly lower in the experimental groups compared with control groups (WMD=−11.42 [95% CI= −16.82, −9.72], I(2) =0%). Conclusion low level laser therapy is an effective therapeutic intervention in reduction of the symptoms of burning mouth syndrome.

  12. Excimer laser irradiation of metal surfaces

    Science.gov (United States)

    Kinsman, Grant

    In this work a new method of enhancing CO2 laser processing by modifying the radiative properties of a metal surface is studied. In this procedure, an excimer laser (XeCl) or KrF) exposes the metal surface to overlapping pulses of high intensity, 10(exp 8) - 10(exp 9) W cm(exp -2), and short pulse duration, 30 nsec FWHM (Full Width Half Maximum), to promote structural and chemical change. The major processing effect at these intensities is the production of a surface plasma which can lead to the formation of a laser supported detonation wave (LSD wave). This shock wave can interact with the thin molten layer on the metal surface influencing to a varying degree surface oxidation and roughness features. The possibility of the expulsion, oxidation and redeposition of molten droplets, leading to the formation of micron thick oxide layers, is related to bulk metal properties and the incident laser intensity. A correlation is found between the expulsion of molten droplets and a Reynolds number, showing the interaction is turbulent. The permanent effects of these interactions on metal surfaces are observed through scanning electron microscopy (SEM), transient calorimetric measurements and Fourier transform infrared (FTIR) spectroscopy. Observed surface textures are related to the scanning procedures used to irradiate the metal surface. Fundamental radiative properties of a metal surface, the total hemispherical emissivity, the near-normal spectral absorptivity, and others are examined in this study as they are affected by excimer laser radiation. It is determined that for heavily exposed Al surface, alpha' (10.6 microns) can be increased to values close to unity. Data relating to material removal rates and chemical surface modification for excimer laser radiation is also discussed. The resultant reduction in the near-normal reflectivity solves the fundamental problem of coupling laser radiation into highly reflective and conductive metals such as copper and aluminum. The

  13. Fundamentals of laser pulse irradiation of silicon

    International Nuclear Information System (INIS)

    Rimini, E.; Baeri, P.; Russo, G.

    1985-01-01

    A computer model has been developed to describe the space and time evolution of carrier concentration, carrier energy and lattice temperature during nanosecond and picosecond laser pulse irradiation of Si single crystals. In particular the dynamic response has been evaluated for energy density of the ps laser pulse below and above the density threshold for surface melting. The obtained data allow a comparison with time-resolved reflectivity measurements reported in the literature. The available data are fitted by the computer model assuming a relaxation time for the energy transfer from the carriers to the lattice of 1 ps. The validity of the thermal model used to describe laser annealing in the nanosecond regime is assessed. (author)

  14. Efeitos da laserterapia de baixa potência na reposta oxidativa epidérmica induzida pela cicatrização de feridas Effects of low-level laser therapy on epidermal oxidative response induced by wound healing

    Directory of Open Access Journals (Sweden)

    PCL Silveira

    2009-08-01

    Full Text Available INTRODUÇÃO: O uso terapêutico do laser de baixa potência na fisioterapia tem aumentado significativamente. OBJETIVO: Avaliar os efeitos da laserterapia de baixa potência nos parâmetros oxidativos na cicatrização de feridas em ratos. MÉTODOS: Dezoito ratos Wistar foram divididos randomicamente em 3 grupos (controle 5 dias, n=6; 5 dias/2 J/cm², n=6; 5 dias/4 J/cm², n=6. Uma única ferida circular medindo 8 X 8 mm foi cirurgicamente realizada no dorso do rato. Trinta minutos após a última irradiação, os ratos foram submetidos à eutanásia, e o tecido irradiado foi removido cirurgicamente e armazenado a -70ºC. Foi determinada a atividade das enzimas da cadeia respiratória: DCIP oxirredutase (complexo II e succinato desidrogenase solúvel (SDH, atividade do citocromo c oxidase (complexo IV, produção de ânion superóxido, atividade da superóxido dismutase (SOD e catalase (CAT. A lipoperoxidação foi avaliada pela técnica de TBARS. RESULTADOS: Os resultados mostram uma diminuição na atividade do complexo II nos grupos irradiados por 5 dias com 2 e 4 J/cm², enquanto a produção de ânion superóxido mostrou uma diminuição significativa no grupo irradiado por 5 dias com 4 J/cm² em relação ao grupo controle. Além disso, um aumento significativo na atividade da catalase foi observado no grupo irradiado por 5 dias com 2 J/cm², como também uma diminuição da peroxidação lipídica nos dois grupos irradiados. CONCLUSÕES: Os resultados do presente estudo indicam que o laser estimula a atividade antioxidante e protege a célula contra danos oxidativos durante o processo de cicatrização de feridas cutâneas em ratos.BACKGROUND: Therapeutic use of low-level laser in physical therapy has increased significantly. OBJECTIVE: To assess the effects of low-level laser therapy on the oxidative parameters of wound healing in rats. METHODS: Eighteen Wistar rats were randomly divided into three groups (control, 5 days, n=6; 2 J

  15. Efeitos do laser de baixa potência sobre a dor e edema no trauma tendíneo de ratos Effects of the low level laser over pain and edema in tendon trauma of rats

    Directory of Open Access Journals (Sweden)

    Gladson Ricardo Flor Bertolini

    2008-08-01

    repair, thus gain body the use of physical resources for the process control. The aim of this study was to evaluate the use of low level laser therapy on the pain and edema of the rats calcaneus tendon, subjected to experimental trauma. We used 28 rats Wistar, divided into four groups: GC - subjected to traumatic injury and the placebo treatment; G2 - subject to injury and irradiated with laser 2 J/cm²; G4 - subject to injury and irradiated with 4 J/cm²; G8 - submitted to injury and irradiated with 8 J/cm². The lesion was performed with the fall of a weight on the side of the right calcaneus tendon of each animal, with energy of about 0.40 J. The pain was evaluated by the paw elevation time (PET for a minute, the animal walking on a metal cylinder with 30 cm in diameter at 3 rpm; the edema evaluation occurred through caliper; moments of the evaluation were: after and before injury, before treatment, 2 hours, 8 hours, 24 hours and 5th injury day. Treatment with laser 670 nm, was so punctual and daily. The results showed increases in PET and formation of edema in all groups after the injury, and for the groups treated there were reducing the pain and edema, being observed in the control group only with the edema reduction in the 5th placebo day. We concluded that the treatment with low level laser therapy decreased the pain and edema of the animals with tendon trauma, in a dose-dependent manner.

  16. Low level laser therapy (GaAlInP 660 nm) in healing of a chronic venous ulcer: a case study

    International Nuclear Information System (INIS)

    Botaro, C A; Faria, L A; Oliveira, R G; Bruno, R X; Rocha, C A Q C; Paiva-Oliveira, E L

    2015-01-01

    The venous ulcer represents approximately 70% to 90% of inferior member ulcers, and the most common etiological factor is venous insufficiency, triggered by venous hypertension. Currently in Brazil there are several types of lasers used in physiotherapy, which benefit biological potential, emitting low power radiation, with anti-inflammatory, analgesic, healing and circulatory effects. This study aimed at the analysis of low level laser therapy effects (LLLT) on the process of tissue repair in chronic venous ulcers. We conducted a case study of a patient with a venous ulcer in the lateral region of the right inferior member. The patient underwent LLLT, which used a GaAlInP diode laser, with a wavelength of 660 nm and energy density of 4 J cm −2 applied punctually at the edges of the wound, with an average distance of 1 cm between the points with a pen-laser perpendicular wrapped in paper and a plastic wrap, keeping contact with the tissue. After four months of therapy and a total of 21 sessions, an improvement was noticeable in the gross appearance of the wound, but after a month and a half without therapy, the dimensions of the wound increased in length and width. Analyzing the results of this case study allows us to conclude that the LLLT GaAlInP (660 nm) with an energy density of 4 J cm −2 , was not successful in the healing of venous ulcers. (paper)

  17. Low level laser therapy (GaAlInP 660 nm) in healing of a chronic venous ulcer: a case study

    Science.gov (United States)

    Botaro, C. A.; Faria, L. A.; Oliveira, R. G.; Bruno, R. X.; Rocha, C. A. Q. C.; Paiva-Oliveira, E. L.

    2015-07-01

    The venous ulcer represents approximately 70% to 90% of inferior member ulcers, and the most common etiological factor is venous insufficiency, triggered by venous hypertension. Currently in Brazil there are several types of lasers used in physiotherapy, which benefit biological potential, emitting low power radiation, with anti-inflammatory, analgesic, healing and circulatory effects. This study aimed at the analysis of low level laser therapy effects (LLLT) on the process of tissue repair in chronic venous ulcers. We conducted a case study of a patient with a venous ulcer in the lateral region of the right inferior member. The patient underwent LLLT, which used a GaAlInP diode laser, with a wavelength of 660 nm and energy density of 4 J cm-2 applied punctually at the edges of the wound, with an average distance of 1 cm between the points with a pen-laser perpendicular wrapped in paper and a plastic wrap, keeping contact with the tissue. After four months of therapy and a total of 21 sessions, an improvement was noticeable in the gross appearance of the wound, but after a month and a half without therapy, the dimensions of the wound increased in length and width. Analyzing the results of this case study allows us to conclude that the LLLT GaAlInP (660 nm) with an energy density of 4 J cm-2, was not successful in the healing of venous ulcers.

  18. Sublethal effects of tritium on aquatic systems, effects of low-level chronic irradiation on embryonic development, effects of beryllium and lithium on aquatic systems, and teratogenic effects of low-level magnetic fields

    International Nuclear Information System (INIS)

    Strand, J.A.; Roesijadi, G.; Emery, R.M.

    1978-01-01

    It is conceivable, and possible, that with increasing applications of nuclear energy, greater quantities of potentially harmful radionuclides will be released to the environment. This may be particularly true for advanced reactor designs such as the fusion reactor where radionuclides, principally tritium, may be expected to escape from the plant both in gaseous and liquid effluents in quantities significantly greater than for present PWR or BWR designs. Foreseeing such contingencies, the research programs described herein are in response to the need to measure the potential radiation effects of tritium releases on individuals, and ultimately populations and biotic communities. As a first approach, our efforts are directed to determine effects of low-level chronic exposures on developing embryo and larval stages, clearly the most radiosensitive. The anticipated increase in the release of beryllium and lithium from mining, refining, and fabrication of materials used during construction of fusion reactors has also caused concern as to potential adverse effects on the environment. Accordingly, FY-78 fusion related research will include efforts to study the metabolism of each metal in the living organism, and to determine at what levels toxicity may be expected. Fusion related research will also include preliminary experiments on the effects of low-level magnetic fields. It is conceivable that magnetic fields of 70 to 450 gauss will be encountered by attendant personnel working in the transport and hot cell areas of fusion reactors. Also, those personnel assigned to the areas immediately surrounding the reactor may be exposed

  19. The effect of low-level laser on pain in patients with facture%半导体激光对骨折后疼痛的疗效观察

    Institute of Scientific and Technical Information of China (English)

    张婷; 谢琪; 王健; 张舒平; 王育庆; 章莹; 谢会斌

    2014-01-01

    Objective: To assess the influence of low- level laser irradiation on the clinical function in patients with facture. Materials 66 patients with facture were randomly divided into drug group (control group) and assisted laser group (experimental group), with 33cases in each group. All the patients in two groups received the same speci-fication medication. While patients in experimental group additionally treated with OMEGA-2001 semiconductor la-ser (UK) for 5 minutes on each irradiation sites daily. The visual analogue scale( VAS) was used to assess the pain in two groups. Results:VAS scores in experimental group were significantly lower than that in control group( P<0.05 ). Conclusion: Early application of low-level semiconductor laser may be an alternative to relieve pain due to fracture in patients.%目的:观察半导体激光对骨折后疼痛的疗效。方法:骨折后疼痛患者66例,骨折已行复位固定,将患者随机分为单纯药物组,药物联合半导体激光组两组,单纯药物组使用美洛昔康,7.5mg/次,2次/日。联合激光组在此基础上加用半导体激光治疗,距离皮肤3cm,照射面积10cm2,每个痛点照射5min,1次∕日。两组均于治疗前、干预后第一天、第二天、第三天、一周、两周进行视觉模拟评分评价。结果:治疗前两组差异无统计学意义(P>0.05);干预2周后单纯药物组的VAS评分0.63±0.74,联合半导体激光组的VAS评分0.36±0.48,两组VAS评分差异有统计学意义(P<0.05)。结论:药物联合半导体激光比单纯药物治疗更能有效减轻骨折后疼痛。

  20. Method for mounting laser fusion targets for irradiation

    Science.gov (United States)

    Fries, R. Jay; Farnum, Eugene H.; McCall, Gene H.

    1977-07-26

    Methods for preparing laser fusion targets of the ball-and-disk type are disclosed. Such targets are suitable for irradiation with one or two laser beams to produce the requisite uniform compression of the fuel material.

  1. Action of low-power laser irradiation on the proliferation of human gingival fibroblasts in vitro

    Science.gov (United States)

    Almeida-Lopes, Luciana; Jaeger, Marcia M. M.; Brugnera, Aldo, Jr.; Rigau, Josepa

    1998-04-01

    The low level power laser has been used in dental treatments aiming to improve tissue healing. An in vitro study was performed to analyze the laser influence on gingival fibroblast. A human gingival fibroblast culture (LMF) was produced in DME medium with 10% bovine fetal serum (BFS) cells (LMF) were allocated in Petri plates and cultured in different SFB concentrations (0%, 5% e 10%). After 48 hours the plates were divided in 9 groups: 3 control: 3 irradiated by 635 nm laser; and 3 irradiated by 780 nm laser. The cultured cells received 4 applications, in 12 hours intervals, with energy dosage of 2 joules for each plate, by means of a punctual technique. The growth curves showed that the growth levels were lower in low BFS concentrations. The irradiation with laser accelerated the growth rate in all groups. Additionally, the number of cells developed in low BFS concentration (5%) and irradiated was similar to the number of control cells developed in ideal conditions (10% BFS). There was no statistically significant differences between the effects of the two types of laser studied.

  2. Long-term changes in open field activity of male mice irradiated with low levels of gamma rays at late stage of development

    International Nuclear Information System (INIS)

    Minamisawa, Takeru; Hirokaga, Kouichi.

    1996-01-01

    The open field activity of first generation (F 1 ) hybrid male C57BL/6 x C3H mice irradiated with γ-rays on the 14th day of gestation was studied at the following ages: 6-7 months, 12-13 months and 19-20 months. Doses were 0.1 Gy or 0.2 Gy. Open field activity was recorded with a camera. The camera output signal was recorded every sec through an A/D converter to a personal computer. The field was divided into 25 units of 8 cm square. All recordings were continuous for 60 min. The time which the 0.2-Gy group recorded at 6-7 months, spent in the 4 squares in the corner fields was high in comparison with the control group at the same age. The walking distance of the 0.1-Gy group recorded at 12-13 months was longer than that for the age matched control group. No effect of radiation was found on any of the behaviors observed and recorded at 19-20 months. The results demonstrate that exposure to low levels of γ-rays on the 14th day of gestation results in behavioral changes, which occur at 6-7 and 12-13 months but not 19-20 months. (author)

  3. Long-term changes in open field activity of male mice irradiated with low levels of gamma rays at late stage of development.

    Science.gov (United States)

    Minamisawa, T; Hirokaga, K

    1996-06-01

    The open field activity of first generation (F1) hybrid male C57BL/6 x C3H mice irradiated with gamma-rays on the 14th day of gestation was studied at the following ages: 6-7 months, 12-13 months and 19-20 months. Doses were 0.1 Gy or 0.2 Gy. Open field activity was recorded with a camera. The camera output signal was recorded every sec through an A/D converter to a personal computer. The field was divided into 25 units of 8 cm square. All recordings were continuous for 60 min. The time which the 0.2-Gy group recorded at 6-7 months, spent in the 4 squares in the corner fields was high in comparison with the control group at the same age. The walking distance of the 0.1-Gy group recorded at 12-13 months was longer than that for the age matched control group. No effect of radiation was found on any of the behaviors observed and recorded at 19-20 months. The results demonstrate that exposure to low levels of gamma-rays on the 14th day of gestation results in behavioral changes, which occur at 6-7 and 12-13 months but not 19-20 months.

  4. Long-term changes in open field activity of male mice irradiated with low levels of gamma rays at late stage of development

    Energy Technology Data Exchange (ETDEWEB)

    Minamisawa, Takeru [Yamanashi Medical Univ., Tamaho (Japan); Hirokaga, Kouichi

    1996-06-01

    The open field activity of first generation (F{sub 1}) hybrid male C57BL/6 x C3H mice irradiated with {gamma}-rays on the 14th day of gestation was studied at the following ages: 6-7 months, 12-13 months and 19-20 months. Doses were 0.1 Gy or 0.2 Gy. Open field activity was recorded with a camera. The camera output signal was recorded every sec through an A/D converter to a personal computer. The field was divided into 25 units of 8 cm square. All recordings were continuous for 60 min. The time which the 0.2-Gy group recorded at 6-7 months, spent in the 4 squares in the corner fields was high in comparison with the control group at the same age. The walking distance of the 0.1-Gy group recorded at 12-13 months was longer than that for the age matched control group. No effect of radiation was found on any of the behaviors observed and recorded at 19-20 months. The results demonstrate that exposure to low levels of {gamma}-rays on the 14th day of gestation results in behavioral changes, which occur at 6-7 and 12-13 months but not 19-20 months. (author)

  5. Application and possible mechanisms of combining LLLT (low level laser therapy), infrared hyperthermia and ionizing radiation in the treatment of cancer

    Science.gov (United States)

    Abraham, Edward H.; Woo, Van H.; Harlin-Jones, Cheryl; Heselich, Anja; Frohns, Florian

    2014-02-01

    Benefit of concomitant infrared hyperthermia and low level laser therapy and ionizing radiation is evaluated in this study. The purpose/objectives: presentation with locally advanced bulky superficial tumors is clinically challenging. To enhance the efficacy of chemotherapy and IMRT (intensity-modulated radiation therapy) and/or electron beam therapy we have developed an inexpensive and clinically effective infrared hyperthermia approach that combines black-body infrared radiation with halogen spectrum radiation and discrete wave length infrared clinical lasers LLLT. The goal is to produce a composite spectrum extending from the far infrared to near infrared and portions of the visible spectrum with discrete penetrating wavelengths generated by the clinical infrared lasers with frequencies of 810 nm and/or 830 nm. The composite spectrum from these sources is applied before and after radiation therapy. We monitor the surface and in some cases deeper temperatures with thermal probes, but use an array of surface probes as the limiting safe thermal constraint in patient treatment while at the same time maximizing infrared entry to deeper tissue layers. Fever-grade infrared hyperthermia is produced in the first centimeters while non-thermal infrared effects act at deeper tissue layers. The combination of these effects with ionizing radiation leads to improved tumor control in many cancers.

  6. Architecture design of the application software for the low-level RF control system of the free-electron laser at Hamburg

    International Nuclear Information System (INIS)

    Geng, Z.; Ayvazyan, V.; Simrock, S.

    2012-01-01

    The superconducting linear accelerator of the Free-Electron Laser at Hamburg (FLASH) provides high performance electron beams to the lasing system to generate synchrotron radiation to various users. The Low-Level RF (LLRF) system is used to maintain the beam stabilities by stabilizing the RF field in the superconducting cavities with feedback and feed forward algorithms. The LLRF applications are sets of software to perform RF system model identification, control parameters optimization, exception detection and handling, so as to improve the precision, robustness and operability of the LLRF system. In order to implement the LLRF applications in the hardware with multiple distributed processors, an optimized architecture of the software is required for good understandability, maintainability and extendibility. This paper presents the design of the LLRF application software architecture based on the software engineering approach for FLASH. (authors)

  7. Effect of Equal Daily Doses Achieved by Different Power Densities of Low-Level Laser Therapy at 635 nm on Open Skin Wound Healing in Normal and Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Róbert Kilík

    2014-01-01

    Full Text Available Background and Objective. Despite the fact that the molecular mechanism of low-level laser therapy (LLLT is not yet known, the exploitation of phototherapy in clinical medicine and surgery is of great interest. The present study investigates the effects of LLLT on open skin wound healing in normal and diabetic rats. Materials and Methods. Four round full-thickness skin wounds on dorsum were performed in male adult nondiabetic (n=24 and diabetic (n=24 Sprague–Dawley rats. AlGaInP (635 nm, wavelength; 5 J/cm2, daily dose was used to deliver power densities of 1, 5, and 15 mW/cm2 three times daily until euthanasia. Results. PMNL infiltration was lower in the irradiated groups (15 mW/cm2. The synthesis and organisation of collagen fibres were consecutively enhanced in the 5 mW/cm2 and 15 mW/cm2 groups compared to the others in nondiabetic rats. In the diabetic group the only significant difference was recorded in the ratio PMNL/Ma at 15 mW/cm2. A significant difference in the number of newly formed capillaries in the irradiated group (5, 15 mW/cm2 was recorded on day six after injury compared to the control group. Conclusion. LLLT confers a protective effect against excessive inflammatory tissue response; it stimulates neovascularization and the early formation of collagen fibres.

  8. Low level laser therapy for concurrent chemoradiotherapy induced oral mucositis in head and neck cancer patients – A triple blinded randomized controlled trial

    International Nuclear Information System (INIS)

    Gautam, Ajay Prashad; Fernandes, Donald J.; Vidyasagar, Mamidipudi S.; Maiya, Arun G.; Vadhiraja, Bejadi M.

    2012-01-01

    Background and purpose: Oral mucositis (OM) is most cumbersome acute side effect of concurrent chemoradiotherapy (CCRT) for head and neck cancer (HNC). OM associated pain affects oral functions and nutrition of the patient that may result in discontinuity of treatment. Several modalities have been tried to prevent and treat OM, but none proved completely successful until date. We used prophylactic low level laser therapy (LLLT) for the prevention and treatment of CCRT induced OM. Materials and methods: In this triple blinded study, 221 HNC patients scheduled to undergo CCRT (Cisplatin (1, 22, 43 day) + RT = 66 Grays (2 Gy/fraction), 33 fractions, 5 fractions/week, for 45 days) were block randomized into laser (n = 111) and placebo (n = 110) group. Laser group received LLLT (HeNe, λ = 632.8 nm, power-density = 24 mW, dosage = 3.0 J/point, total dosage/session = 36–40 J, spot-size = 1 cm 2 , 5 sessions/week) while placebo received sham treatment daily prior to radiation. OM (RTOG/EORTC Scale), oral pain (VAS), dysphagia (FIS), weight loss and CCRT break were assessed. Data were analyzed using frequencies and percentage, generalized estimating equations (GEE) and odds ratio. Results: There was significant reduction in incidence of severe OM (F = 16.64, df = 8876, p < 0.0001) and its associated pain (F = 25.06, df = 8876, p < 0.0001), dysphagia (F = 20.17, df = 8876, p < 0.0001) and opioid analgesics use (p < 0.0001) in laser than placebo group patients. Conclusions: LLLT decreased the incidence of CCRT induced severe OM and its associated pain, dysphagia and opioid analgesics use.

  9. Kinetics of laser irradiated nanoparticles cloud

    Science.gov (United States)

    Mishra, S. K.; Upadhyay Kahaly, M.; Misra, Shikha

    2018-02-01

    A comprehensive kinetic model describing the complex kinetics of a laser irradiated nanoparticle ensemble has been developed. The absorbed laser radiation here serves dual purpose, viz., photoenhanced thermionic emission via rise in its temperature and direct photoemission of electrons. On the basis of mean charge theory along with the equations for particle (electron) and energy flux balance over the nanoparticles, the transient processes of charge/temperature evolution over its surface and mass diminution on account of the sublimation (phase change) process have been elucidated. Using this formulation phenomenon of nanoparticle charging, its temperature rise to the sublimation point, mass ablation, and cloud disintegration have been investigated; afterwards, typical timescales of disintegration, sublimation and complete evaporation in reference to a graphite nanoparticle cloud (as an illustrative case) have been parametrically investigated. Based on a numerical analysis, an adequate parameter space describing the nanoparticle operation below the sublimation temperature, in terms of laser intensity, wavelength and nanoparticle material work function, has been identified. The cloud disintegration is found to be sensitive to the nanoparticle charging through photoemission; as a consequence, it illustrates that radiation operating below the photoemission threshold causes disintegration in the phase change state, while above the threshold, it occurs with the onset of surface heating.

  10. Role of Low-Level Laser Therapy as an Adjunct to Initial Periodontal Treatment in Type 2 Diabetic Patients: A Split-Mouth, Randomized, Controlled Clinical Trial.

    Science.gov (United States)

    Demirturk-Gocgun, Oya; Baser, Ulku; Aykol-Sahin, Gokce; Dinccag, Nevin; Issever, Halim; Yalcin, Funda

    2017-02-01

    In this split-mouth clinical trial, we evaluated the clinical benefits of low-level laser therapy (LLLT) as an adjunct to nonsurgical periodontal treatment in patients with type 2 diabetes mellitus (DM). The impaired wound healing seen in diabetic patients may affect the results of periodontal treatment and may require an additional approach. In total, 22 chronic periodontitis patients with type 2 DM were included. Applying a split-mouth design, two quadrants were treated with only scaling and root planing (SRP) as the control and those in the other two were treated with SRP + LLLT as the test sites in each patient. An 808 nm GaAlAs diode laser was performed in the test sites at the energy density of 4.46 J/cm 2 on days 1, 2, and 7 after SRP. Plaque index (PI), probing depth (PD), bleeding on probing (BOP), and clinical attachment level were measured at baseline and again at 1 and 3 months after treatment. Deep periodontal pockets (PD ≥4 mm) were evaluated separately. Test sites showed significant improvement in PI and BOP in deep pockets at the 1-month follow-up period (p < 0.001 and <0.001, respectively), whereas no difference was found between the control and the test sites in other periodontal parameters. LLLT during periodontal treatment offered minimal short-term additional benefit in deep pocket healing in patients with type 2 DM.

  11. Low-level laser therapy (LLLT) does not reduce subcutaneous adipose tissue by local adipocyte injury but rather by modulation of systemic lipid metabolism.

    Science.gov (United States)

    Jankowski, Marek; Gawrych, Mariusz; Adamska, Urszula; Ciescinski, Jakub; Serafin, Zbigniew; Czajkowski, Rafal

    2017-02-01

    Low-level laser (light) therapy (LLLT) has been applied recently to body contouring. However the mechanism of LLLT-induced reduction of subcutaneous adipose tissue thickness has not been elucidated and proposed hypotheses are highly controversial. Non-obese volunteers were subject to 650nm LLLT therapy. Each patient received 6 treatments 2-3 days apart to one side of the abdomen. The contralateral side was left untreated and served as control. Subjects' abdominal adipose tissue thickness was measured by ultrasound imaging at baseline and 2 weeks post-treatment. Our study is to the best of our knowledge, the largest split-abdomen study employing subcutaneous abdominal fat imaging. We could not show a statistically significant reduction of abdominal subcutaneous adipose tissue by LLLT therapy. Paradoxically when the measurements of the loss of fat thickness on treated side was corrected for change in thickness on non treated side, we have observed that in 8 out of 17 patients LLLT increased adipose tissue thickness. In two patients severe side effect occurred as a result of treatment: one patient developed ulceration within appendectomy scar, the other over the posterior superior iliac spine. The paradoxical net increase in subcutaneous fat thickness observed in some of our patients is a rationale against liquefactive and transitory pore models of LLLT-induced adipose tissue reduction. LLLT devices with laser diode panels applied directly on the skin are not as safe as devices with treatment panels separated from the patient's skin.

  12. The effects of Low Level LASER Therapy (LLLT) on blood glucose levels in patients with Diabetes Mellitus type I : a case report

    Science.gov (United States)

    Longo, Leonardo; Postiglione, Marco; Buccioni, Tommaso; Longo, Diego

    2009-06-01

    Diabetes Mellitus (DM) is a widespread disease and a serious public health problem. Low Level LASER Therapy (LLLT) has been found to reduce glycaemia on DM type 1 patients, an observation requiring further research especially as regards characteristics of treatment protocol. The purpose of this work is to continue the line of research and propose a specific protocol for LLLT use. In spring 2008 a 48 year old man, DM type 1 insulin dependent patient has been submitted to 810 nm wavelength LLLT treatment in specific body areas daily for 3 weeks and then once a week for 4 weeks until normalization of glycaemia. Medical supervision was present before, during and after application. Insulin was reduced progressively and then stopped. A gradual reduction of glycaemia was noted during the course of treatment. In successive follow-ups a reduction in HbA1c was noted. Results confirm previous observations and need for further research on large cohorts. The indication that LASER may become a valuable addition to DM type 1 treatment is confirmed and the proposed protocol appears to be effective. The case presented merits review since it reports a therapeutic challenge, contributes to advance in medical science and spawns research.

  13. Low-Level Laser Therapy Reduces Lung Inflammation in an Experimental Model of Chronic Obstructive Pulmonary Disease Involving P2X7 Receptor

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    Gabriel da Cunha Moraes

    2018-01-01

    Full Text Available Chronic obstructive pulmonary disease (COPD is a progressive disease characterized by irreversible airflow limitation, airway inflammation and remodeling, and enlargement of alveolar spaces. COPD is in the top five leading causes of deaths worldwide and presents a high economic cost. However, there are some preventive measures to lower the risk of developing COPD. Low-level laser therapy (LLLT is a new effective therapy, with very low cost and no side effects. So, our objective was to investigate if LLLT reduces pulmonary alterations in an experimental model of COPD. C57BL/6 mice were submitted to cigarette smoke for 75 days (2x/day. After 60 days to smoke exposure, the treated group was submitted to LLLT (diode laser, 660 nm, 30 mW, and 3 J/cm2 for 15 days and euthanized for morphologic and functional analysis of the lungs. Our results showed that LLLT significantly reduced the number of inflammatory cells and the proinflammatory cytokine secretion such as IL-1β, IL-6, and TNF-α in bronchoalveolar lavage fluid (BALF. We also observed that LLLT decreased collagen deposition as well as the expression of purinergic P2X7 receptor. On the other hand, LLLT increased the IL-10 release. Thus, LLLT can be pointed as a promising therapeutic approach for lung inflammatory diseases as COPD.

  14. Effects of corticopuncture (CP) and low-level laser therapy (LLLT) on the rate of tooth movement and root resorption in rats using micro-CT evaluation.

    Science.gov (United States)

    Suzuki, Selly Sayuri; Garcez, Aguinaldo Silva; Reese, Patricia Oblitas; Suzuki, Hideo; Ribeiro, Martha Simões; Moon, Won

    2018-05-01

    The aim of this study was to compare the rate of tooth displacement, quantity of root resorption, and alveolar bone changes in five groups: corticopuncture (CP), low-level laser therapy (LLLT), CP combined with LLLT (CP + LLLT), control (C), and negative control (NC). A total of 60 half-maxilla from 30 male Wistar rats (10 weeks old) were divided randomly into five groups: three (CP, LLLT, and CP + LLLT) test groups with different stimulation for accelerated-tooth-movement (ATM), one control (C) group, and one negative control (NC) group with no tooth movement. Nickel-titanium coil springs with 50 g of force were tied from the upper left and right first molars to micro-implants placed behind the maxillary incisors. For the CP and CP + LLLT groups, two perforations in the palate and one mesially to the molars were performed. For the LLLT and CP + LLLT groups, GaAlAs diode laser was applied every other day for 14 days (810 nm, 100 mW, 15 s). The tooth displacements were measured directly from the rat's mouth and indirectly from microcomputer (micro-CT) tomographic images. Bone responses at the tension and compression sites and root resorption were analyzed from micro-CT images. The resulting alveolar bone responses were evaluated by measuring bone mineral density (BMD), bone volume fraction (BV/TV), and trabecular thickness (TbTh). Root resorption crater volumes were measured on both compression and tension sides of mesial and distal buccal roots. The tooth displacement in the CP + LLLT group was the greatest when measured clinically, followed by the CP, LLLT, and control groups (C and NC), respectively (p CP and CP + LLLT groups compared to the LLLT and control groups. The BMD, BV/TV, and TbTh values were lower at the compression side and higher at the tension side for all three test groups compared to the control group. The root resorption crater volume of the distal buccal root was higher in the control group, followed by CP, LLLT

  15. The Effects of Remineralization via Fluoride Versus Low-Level Laser IR810 and Fluoride Agents on the Mineralization and Microhardness of Bovine Dental Enamel

    Directory of Open Access Journals (Sweden)

    Edith Lara-Carrillo

    2018-01-01

    Full Text Available The objective of this study was to assess the mineralization and microhardness of bovine dental enamel surfaces treated with fluoride, tri-calcium phosphate, and infrared (IR 810 laser irradiation. The study used 210 bovine incisors, which were divided into six groups (n = 35 in each: Group A: Untreated (control, Group B: Fluoride (Durapath-Colgate, Group C: Fluoride+Tri-calcium phosphate (Clin-Pro White-3 M, Group D: Laser IR 810 (Quantum, Group E: Fluoride+laser, and Group F: Fluoride+tri-calcium phosphate+laser. Mineralization was measured via UV-Vis spectroscopy for phosphorus and via atomic absorption spectroscopy for calcium upon demineralization and remineralization with proven agents. Microhardness (SMH was measured after enamel remineralization. Mineral loss data showed differences between the groups before and after the mineralizing agents were placed (p < 0.05. Fluoride presented the highest remineralization tendency for both calcium and phosphate, with a Vickers microhardness of 329.8 HV0.1/11 (p < 0.05. It was observed that, if remineralization solution contained fewer minerals, the microhardness surface values were higher (r = −0.268 and −0.208; p < 0.05. This study shows that fluoride has a remineralizing effect compared with calcium triphosphate and laser IR810. This in vitro study imitated the application of different remineralizing agents and showed which one was the most efficient for treating non-cavitated injuries. This can prevent the progression of lesions in patients with white spot lesions.

  16. Experimental model for low level laser therapy on ischemic random skin flap in rats Modelo experimental para laserterapia de baixa intensidade em retalho cutâneo randômico isquêmico em ratos

    Directory of Open Access Journals (Sweden)

    Rodrigo Paschoal Prado

    2006-08-01

    Full Text Available PURPOSE: To develop an experimental model to be used in the study of low level Laser therapy on viability of random skin flap in rats. METHODS: The sample was 24 Wistar-EPM rats. The random skin flap measured 10 x 4 cm and a plastic sheet was interposed between the flap and donor site. Group 1 (control underwent sham irradiation with diode laser (830 nm. Group 2 was submitted to laser irradiation with diode laser (830 nm. The animals were submitted to Laser therapy with 36 J/cm² energy density (72 seconds immediately after the surgery and on the four subsequent days. The probe was usually held in contact with the skin flap surface on a point at 2.5 cm cranial from the flap base. On the seventh postoperative day, the percentage of necrotic area was measured and calculated. RESULTS: Group 1 reached an average necrotic area of 48.86%, Group 2 - 23.14%. After the statistic analysis, compared with the control group, Group 2 showed a statistically significant increase in survival area (pOBJETIVO: Propor o desenvolvimento de um modelo experimental para verificar o efeito da laserterapia de baixa intensidade na viabilidade do retalho cutâneo randômico em ratos. MÉTODOS: A amostra constituiu-se de 24 ratos, da linhagem Wistar-EPM. O retalho cutâneo randômico foi realizado com dimensões de 10x4 cm e uma barreira plástica foi interposta entre o mesmo e o leito doador. O Grupo 1 (controle, foi submetido a uma simulação de tratamento com a irradiação laser de diodo (830 nm. O Grupo 2 foi submetido à irradiação laser de diodo (830 nm. Os animais foram submetidos a terapia a laser com densidade de energia de 36 J/cm2 (72 segundos imediatamente após a operação e nos outros quatros dias subseqüentes. A caneta do laser foi posicionada a 90 graus em contato com o retalho cutâneo em um ponto a 2,5 cm da base cranial do retalho. No sétimo dia pós-operatório foram calculadas as porcentagens da área de necrose. RESULTADOS: O Grupo 1 apresentou

  17. Impact of low-level laser therapy on hyposalivation, salivary pH, and quality of life in head and neck cancer patients post-radiotherapy.

    Science.gov (United States)

    Palma, Luiz Felipe; Gonnelli, Fernanda Aurora Stabile; Marcucci, Marcelo; Dias, Rodrigo Souza; Giordani, Adelmo José; Segreto, Roberto Araújo; Segreto, Helena Regina Comodo

    2017-05-01

    Late effects of radiotherapy for head and neck cancer treatment have been increasingly investigated due to its impact on patients' quality of life. The purpose of this study was to evaluate the effect of low-level laser therapy on hyposalivation, low salivary pH, and quality of life in head and neck cancer patients post-radiotherapy. Twenty-nine patients with radiation-induced xerostomia received laser sessions twice a week, during 3 months (24 sessions). For this, a continuous wave Indium-Gallium-Aluminium-Phosphorus diode laser device was used punctually on the major salivary glands (808 nm, 0.75 W/cm 2 , 30 mW, illuminated area 0.04 cm 2 , 7.5 J/cm 2 , 10 s, 0.3 J). Six extraoral points were illuminated on each parotid gland and three on each submandibular gland, as well as two intraoral points on each sublingual gland. Stimulated and unstimulated salivary flow rate, pH (two scales with different gradations), and quality of life (University Of Washington Quality of Life Questionnaire for Patients with Head and Neck Cancer) were assessed at baseline and at the end of the treatment. There were significant increases in both mean salivary flow rates (unstimulated: p = 0.0012; stimulated: p quality of life questionnaire (p patients submitted to radiotherapy for head and neck cancer, thereby leading to an improvement in quality of life.

  18. Five-year follow-up of low-level laser therapy (LLLT) in patients with age-related macular degeneration (AMD)

    Science.gov (United States)

    Koev, K.; Avramov, L.; Borissova, E.

    2018-03-01

    The objective of this study was to examine long-term effects of low-level laser therapy (LLLT) in patients with age-related macular degeneration (AMD). The research was implemented for a period of five years. For LLLT, a He-Ne Laser with continuous emission at 633 nm (0.1 mW/cm2) was used in patients with AMD of all stages (dry to wet exudative forms were included). In total, 33 patients (16 men and 17 women – 66 eyes) with AMD of various stages and a mean age of 68.7 ± 4.2 years were included in the study. Progressive, exudative AMD was diagnosed in 8 eyes. 58 eyes had drusen or were depigmented. Laser radiation was applied transpupillary to the macula for six times for three minutes once in two days; 22 patients with AMD (44 eyes) were randomly selected to receive mock treatment (control group 10 men and 12 women with a mean age of 69.3 ± 4.8 years). The visual acuity was followed for a five-year period. The perimetry and Amsler test were used to screen central scotomas. The fluorescein angiography of AMD and the control groups was examined. The visual acuity remained unchanged in all patients in the control group. There was a statistically significant increase in the visual acuity (p<0.001, end of study versus baseline) for AMD patients for the period of five years after the treatment. The edema and hemorrhage in the patients with progressive, exudative AMD significantly decreased. No side effects were observed during the therapy. The prevalence of metamorphopsia, scotoma in AMD group was reduced. In conclusion, this study shows that LLLT may be a novel long-lasting therapeutic option for both forms of AMD. It is a highly-effective treatment that results in a long-term improvement of the visual acuity.

  19. Single event upset threshold estimation based on local laser irradiation

    International Nuclear Information System (INIS)

    Chumakov, A.I.; Egorov, A.N.; Mavritsky, O.B.; Yanenko, A.V.

    1999-01-01

    An approach for estimation of ion-induced SEU threshold based on local laser irradiation is presented. Comparative experiment and software simulation research were performed at various pulse duration and spot size. Correlation of single event threshold LET to upset threshold laser energy under local irradiation was found. The computer analysis of local laser irradiation of IC structures was developed for SEU threshold LET estimation. The correlation of local laser threshold energy with SEU threshold LET was shown. Two estimation techniques were suggested. The first one is based on the determination of local laser threshold dose taking into account the relation of sensitive area to local irradiated area. The second technique uses the photocurrent peak value instead of this relation. The agreement between the predicted and experimental results demonstrates the applicability of this approach. (authors)

  20. Low level waste repositories

    International Nuclear Information System (INIS)

    Hill, P.R.H.; Wilson, M.A.

    1983-11-01

    Factors in selecting a site for low-level radioactive waste disposal are discussed. South Australia has used a former tailings dam in a remote, arid location as a llw repository. There are also low-level waste disposal procedures at the Olympic Dam copper/uranium project

  1. The effect of low-level laser therapy on oxidative stress and functional fitness in aged rats subjected to swimming: an aerobic exercise.

    Science.gov (United States)

    Guaraldo, Simone A; Serra, Andrey Jorge; Amadio, Eliane Martins; Antônio, Ednei Luis; Silva, Flávio; Portes, Leslie Andrews; Tucci, Paulo José Ferreira; Leal-Junior, Ernesto Cesar Pinto; de Carvalho, Paulo de Tarso Camillo

    2016-07-01

    The aim of the present study was to determine whether low-level laser therapy (LLLT) in conjunction with aerobic training interferes with oxidative stress, thereby influencing the performance of old rats participating in swimming. Thirty Wistar rats (Norvegicus albinus) (24 aged and six young) were tested. The older animals were randomly divided into aged-control, aged-exercise, aged-LLLT, aged-LLLT/exercise, and young-control. Aerobic capacity (VO2max(0.75)) was analyzed before and after the training period. The exercise groups were trained for 6 weeks, and the LLLT was applied at 808 nm and 4 J energy. The rats were euthanized, and muscle tissue was collected to analyze the index of lipid peroxidation thiobarbituric acid reactive substances (TBARS), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activities. VO2 (0.75)max values in the aged-LLLT/exercise group were significantly higher from those in the baseline older group (p exercise group (p exercise group than those in the LLLT and exercise groups. Young animals presented lesser and statistically significant activities of antioxidant enzymes compared to the aged group. The LLLT/exercise group and the LLLT and exercise group could also mitigate the concentration of TBARS (p > 0.05). Laser therapy in conjunction with aerobic training may reduce oxidative stress, as well as increase VO2 (0.75)max, indicating that an aerobic exercise such as swimming increases speed and improves performance in aged animals treated with LLLT.

  2. Phase III trial of low-level laser therapy to prevent oral mucositis in head and neck cancer patients treated with concurrent chemoradiation

    International Nuclear Information System (INIS)

    Antunes, Heliton S.; Herchenhorn, Daniel; Small, Isabele A.; Araújo, Carlos M.M.; Viégas, Celia Maria Pais; Cabral, Elida; Rampini, Mariana P.; Rodrigues, Pedro C.; Silva, Tereza G.P.; Ferreira, Elza M.S.; Dias, Fernando L.; Ferreira, Carlos G.

    2013-01-01

    Background: Oral mucositis (OM) is a complication of chemoradiotherapy treatment of head and neck squamous cell carcinoma (HNSCC) patients with no effective therapy. This study was designed to assess the efficacy of preventive low-level laser therapy (LLLT) in reducing the incidence of grade 3–4 OM. Material and methods: From June 2007 to December 2010, 94 HNSCC patients entered a prospective, randomized, double-blind, placebo-controlled phase III trial. Chemoradiotherapy consisted of conventional radiotherapy plus concurrent cisplatin every 3 weeks. A diode InGaAlP (660 nm–100 mW–1 J–4 J/cm 2 ) was used. OM evaluation was performed by WHO and OMAS scales and quality of life by EORTC questionnaires (QLQ). Results: A six-fold decrease in the incidence of grades 3–4 OM was detected in the LLLT group compared to the placebo; (6.4% versus 40.5%). LLLT impacted the incidence of grades 3–4 OM to a relative risk ratio of 0.158 (CI 95% 0.050–0.498). After treatment QLQ-C30 showed, differences favoring LLLT in physical, emotional functioning, fatigue, and pain; while the QLQ-H and N35 showed improvements in LLLT arm for pain, swallowing, and trouble with social eating. Conclusion: Preventive LLLT in HNSCC patients receiving chemoradiotherapy is an effective tool for reducing the incidence of grade 3–4 OM. Efficacy data were corroborated by improvements seen in quality of life

  3. Effects of low-level laser therapy (LLLT) and diclofenac (topical and intramuscular) as single and combined therapy in experimental model of controlled muscle strain in rats.

    Science.gov (United States)

    de Paiva Carvalho, Rodrigo Leal; Leal-Junior, Ernesto Cesar Pinto; Petrellis, Maria Carla; Marcos, Rodrigo Labat; de Carvalho, Maria Helena Catelli; De Nucci, Gilberto; Lopes-Martins, Rodrigo Alvaro Brandão

    2013-01-01

    Muscle injuries represent ca 30% of sports injuries and excessive stretching of muscle causes more than 90% of injuries. Currently the most used treatments are nonsteroidal anti-inflammatory drugs (NSAIDs), however, in last years, low-level laser therapy (LLLT) is becoming an interesting therapeutic modality. The aim of this study was to evaluate the effect of single and combined therapies (LLLT, topical application of diclofenac and intramuscular diclofenac) on functional and biochemical aspects in an experimental model of controlled muscle strain in rats. Muscle strain was induced by overloading tibialis anterior muscle of rats. Injured groups received either no treatment, or a single treatment with topical or intramuscular diclofenac (TD and ID), or LLLT (3 J, 810 nm, 100 mW) 1 h after injury. Walking track analysis was the functional outcome and biochemical analyses included mRNA expression of COX-1 and COX-2 and blood levels of prostaglandin E2 (PGE2 ). All treatments significantly decreased COX-1 and COX-2 gene expression compared with injury group (P levels and walking track analysis (P topical and intramuscular diclofenac in treatment of muscle strain injury in acute stage. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  4. LED and low level laser therapy association in tooth bleaching using a novel low concentration H2O2/N-doped TiO2 bleaching agent

    Science.gov (United States)

    Bezerra Dias, Hércules; Teixeira Carrera, Emanuelle; Freitas Bortolatto, Janaína; Ferrarezi de Andrade, Marcelo; Nara de Souza Rastelli, Alessandra

    2016-01-01

    Since low concentration bleaching agents containing N-doped TiO2 nanoparticles have been introduced as an alternative to conventional agents, it is important to verify their efficacy and the hypersensitivity effect in clinical practice. Six volunteer patients were evaluated for color change and hypersensitivity after bleaching using 35% H2O2 (one session of two 12 min applications) and 6% H2O2/N-doped TiO2 (one session of three 12 min applications) and after low level laser therapy application (LLLT) (780 nm, 40 mW, 10 J.cm-2, 10 s). Based on this case study, the nanobleaching agent provided better or similar aesthetic results than the conventional agent under high concentration, and its association with LLLT satisfactorily decreased the hypersensitivity. The 6% H2O2/N-doped TiO2 agent could be used instead of conventional in-office bleaching agents under high concentrations to fulfill the rising patient demand for aesthetics.

  5. Effects of wavelength, beam type and size on cerebral low-level laser therapy by a Monte Carlo study on visible Chinese human

    Directory of Open Access Journals (Sweden)

    Ting Li

    2015-01-01

    Full Text Available Low-level laser therapy (LLLT has been clinically utilized for many indications in medicine requiring protection from cell/tissue death, stimulation of healing and repair of injuries, pain reduction, swelling and inflammation. Presently, the use of LLLT to treat stroke, traumatic brain injury and cognitive dysfunction are attracting growing interest. Near-infrared light is capable of penetrating into the cerebral cortex, allowing noninvasive treatments to be carried out with few treatment-related adverse events. Optimization of LLLT treatment effect is a crucial issue of this field; however, only a few experimental tests on mice for wavelength selection have been reported. We addressed this issue by low-cost, straightforward and quantitative comparisons on light dosage distribution within visible Chinese human head by Monte Carlo modeling of near-infrared light propagation. Optimized selection in wavelength, beam type and size were given based on comparisons among frequently used setups (i.e., wavelengths: 660, 810 and 980 nm; beam type: Gaussian and flat beam; beam diameter: 2, 4 and 6 cm. This study provided an efficient way for guiding the optimization of LLLT setup and selection on wavelength, beam type and size for clinical brain LLLT.

  6. Superpulsed low-level laser therapy protects skeletal muscle of mdx mice against damage, inflammation and morphological changes delaying dystrophy progression.

    Science.gov (United States)

    Leal-Junior, Ernesto Cesar Pinto; de Almeida, Patrícia; Tomazoni, Shaiane Silva; de Carvalho, Paulo de Tarso Camillo; Lopes-Martins, Rodrigo Álvaro Brandão; Frigo, Lucio; Joensen, Jon; Johnson, Mark I; Bjordal, Jan Magnus

    2014-01-01

    To evaluate the effects of preventive treatment with low-level laser therapy (LLLT) on progression of dystrophy in mdx mice. Ten animals were randomly divided into 2 experimental groups treated with superpulsed LLLT (904 nm, 15 mW, 700 Hz, 1 J) or placebo-LLLT at one point overlying the tibialis anterior muscle (bilaterally) 5 times per week for 14 weeks (from 6th to 20th week of age). Morphological changes, creatine kinase (CK) activity and mRNA gene expression were assessed in animals at 20th week of age. Animals treated with LLLT showed very few morphological changes in skeletal muscle, with less atrophy and fibrosis than animals treated with placebo-LLLT. CK was significantly lower (p=0.0203) in animals treated with LLLT (864.70 U.l-1, SEM 226.10) than placebo (1708.00 U.l-1, SEM 184.60). mRNA gene expression of inflammatory markers was significantly decreased by treatment with LLLT (pmuscle damage and inflammation in mdx mice. This indicates that LLLT has potential to decrease progression of Duchenne muscular dystrophy.

  7. Tritium-doping enhancement of polystyrene by ultraviolet laser and hydrogen plasma irradiation for laser fusion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Iwasa, Yuki, E-mail: iwasa-y@ile.osaka-u.ac.jp [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Yamanoi, Kohei; Iwano, Keisuke; Empizo, Melvin John F.; Arikawa, Yasunobu; Fujioka, Shinsuke; Sarukura, Nobuhiko; Shiraga, Hiroyuki; Takagi, Masaru; Norimatsu, Takayoshi; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Noborio, Kazuyuki; Hara, Masanori; Matsuyama, Masao [Hydrogen Isotope Research Center, Organization for Promotion of Research, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan)

    2016-11-15

    Highlights: • Tritium-doped polystyrene films are fabricated by the Wilzbach method with UV laser and hydrogen plasma irradiation. • The 266-nm laser-irradiated, 355-nm laser-irradiated, and hydrogen plasma-irradiated polystyrene films exhibit higher PSL intensities and specific radioactivities than the non-irradiated sample. • Tritium doping by UV laser irradiation can be largely affected by the laser wavelength because of polystyrene’s absorption. • Hydrogen plasma irradiation results to a more uniform doping concentration even at low partial pressure and short irradiation time. • UV laser and plasma irradiations can be utilized to fabricate tritium-doped polystyrene shell targets for future laser fusion experiments. - Abstract: We investigate the tritium-doping enhancement of polystyrene by ultraviolet (UV) laser and hydrogen plasma irradiation. Tritium-doped polystyrene films are fabricated by the Wilzbach method with UV laser and hydrogen plasma. The 266-nm laser-irradiated, 355-nm laser-irradiated, and hydrogen plasma-irradiated polystyrene films exhibit higher PSL intensities and specific radioactivities than the non-irradiated sample. Tritium doping by UV laser irradiation can be largely affected by the laser wavelength because of polystyrene’s absorption. In addition, UV laser irradiation is more localized and concentrated at the spot of laser irradiation, while hydrogen plasma irradiation results to a more uniform doping concentration even at low partial pressure and short irradiation time. Both UV laser and plasma irradiations can nevertheless be utilized to fabricate tritium-doped polystyrene targets for future laser fusion experiments. With a high doping rate and efficiency, a 1% tritium-doped polystyrene shell target having 7.6 × 10{sup 11} Bq g{sup −1} specific radioactivity can be obtained at a short period of time thereby decreasing tritium consumption and safety management costs.

  8. Morphological and spectroscopic characterization of laser-ablated tungsten at various laser irradiances

    Energy Technology Data Exchange (ETDEWEB)

    Akram, Mahreen; Bashir, Shazia; Hayat, Asma; Mahmood, Khaliq; Dawood, Asadullah [Government College University, Centre for Advanced Studies in Physics, Lahore (Pakistan); Rafique, Muhammad Shahid [University of Engineering and Technology, Department of Physics, Lahore (Pakistan); Bashir, M.F. [COMSATS Institute of Information Technology, Department of Physics, Lahore (Pakistan)

    2015-06-15

    The variation in surface morphology and plasma parameters of laser irradiated tungsten has been investigated as a function of irradiance. For this purpose, Nd:YAG laser (1064 nm, 10 ns, 10 Hz) is employed. Tungsten targets were exposed to various laser irradiances ranging from 6 to 50 GW/cm{sup 2} under ambient environment of argon at a pressure of 20 Torr. Scanning electron microscope analysis has been performed to analyze the surface modification of irradiated tungsten. It revealed the formation of micro- and nanoscale surface structures. In central ablated area, distinct grains and crack formation are observed, whereas peripheral ablated areas are dominated by cones and pinhole formation. It was observed that at irradiances exceeding a value of 13 GW/cm{sup 2}, the morphological trend of the observed structures has been changed from erosion to melting and re-deposition dominant phase. Ablation efficiency as a function of laser irradiance has also been investigated by measuring the crater depth using surface profilometry analysis. It is found to be maximum at an irradiance of 13 GW/cm{sup 2} and decreases at high laser irradiances. In order to correlate the accumulated effects of plasma parameters with the surface modification, laser-induced breakdown spectroscopy analysis has been performed. The electron temperature and number density of tungsten plasma have been evaluated at various laser irradiances. Initially with the increase of the laser irradiance up to 13 GW/cm{sup 2}, an increasing trend is observed for both plasma parameters due to enhanced energy deposition. Afterward, a decreasing trend is achieved which is attributed to the shielding effect. With further increase in irradiance, a saturation stage comes and insignificant changes are observed in plasma parameters. This saturation is explainable on the basis of the formation of a self-regulating regime near the target surface. Surface modifications of laser irradiated tungsten have been correlated with

  9. Evaluation of muscle activity, bite force and salivary cortisol in children with bruxism before and after low level laser applied to acupoints: study protocol for a randomised controlled trial.

    Science.gov (United States)

    Salgueiro, Mônica da Consolação Canuto; Bortoletto, Carolina Carvalho; Horliana, Anna Carolina RattoTempestini; Mota, Ana Carolina Costa; Motta, Lara Jansiski; Motta, Pamella de Barros; MesquitaFerrari, Raquel Agnelli; Fernandes, Kristianne Porta Santos; Bussadori, Sandra Kalil

    2017-08-08

    Bruxism is a repetitive activity that causes tooth wear, audible sounds, and discomfort. Preventive measures have been studied for conditions that can exert a negative influence on physiological development in children. Low-level laser therapy administered over acupoints is an effective, painless, low-cost treatment option that has achieved good results. Thus, the aim of the proposed study is to evaluate changes in muscle activity, bite force and salivary cortisol in children with bruxism after the application of low-level laser to accupoints. The children will be randomly allocated to four groups of 19 individuals: G1 - low-level laser; G2 - occlusal splint; G3 - placebo laser; and G4 - control (without bruxism). The BTS TMJOINT electromyography will be used to determine muscle activity and a digital gnathodynamometer will be used to measure bite force. Salivary cortisol will be analysed at baseline as well as one and six months after treatment. Two-way ANOVA will be employed and complemented by Tukey's test. Bruxism is a repetitive activity of the masticatory muscles that can have negative consequences if not treated, such as tooth wear, noises, discomfort and anxiety. Thus, control and treatment measures should be taken. Although low-level laser therapy over acupoints has been indicated for children, the effects of this treatment modality have not yet been studied. NCT02757261 on 8 April 2016. This study protocol received a grant from the Brazilian fostering agency São Paulo Research Foundation (FAPESP: #2015/24731-0).

  10. First results of laser welding of neutron irradiated stainless steel

    International Nuclear Information System (INIS)

    Osch, E.V. van; Hulst, D.S. d'; Laan, J.G. van der.

    1994-10-01

    First results of experimental investigations on the laser reweldability of neutron irradiated material are reported. These experiments include the manufacture of 'heterogeneous' joints, which means joining of irradiated stainless steel of type AISI 316L-SPH to 'fresh' unirradiated material. The newly developed laser welding facility in the ECN Hot Cell Laboratory and experimental procedures are described. Visual inspections of welded joints are reported as well as results of electron microscopy and preliminary metallographic examinations. (orig.)

  11. Biomodulatory effects of laser irradiation on dental pulp cells in vitro

    Science.gov (United States)

    Milward, Michael R.; Hadis, Mohammed A.; Cooper, Paul R.; Gorecki, Patricia; Carroll, James D.; Palin, William M.

    2015-03-01

    Low level laser/light therapy (LLLT) or photobiomodulation is a biophysical approach that can be used to reduce pain, inflammation and modulate tissue healing and repair. However, its application has yet to be fully realized for dental disease treatment. The aim of this study was to assess the modulation of dental pulp cell (DPC) responses using two LLLT lasers with wavelengths of 660nm and 810nm. Human DPCs were isolated and cultured in phenol-red-free α- MEM/10%-FCS at 37°C in 5% CO2. Central wells of transparent-based black walled 96-microplates were seeded with DPCs (passages 2-4; 150μL; 25,000 cell/ml). At 24h post-seeding, cultures were irradiated using a Thor Photomedicine LLLT device (THOR Photomedicine, UK) at 660nm (3, 6 or 13s to give 2, 5 and 10J/cm2) or 810nm (for 1, 2 or 5s to deliver 5, 10 and 20J/cm2). Metabolic activity was assessed via a modified MTT assay 24h post-irradiation. Statistical differences were identified using analysis of variance and post-hoc Tukey tests (P=0.05) and compared with nonirradiated controls. Significantly higher MTT activity was obtained for both lasers (P0.05). Consequently, enhanced irradiation parameters was apparent for both lasers. These parameters should be further optimised to identify the most effective for therapeutic application.

  12. Etiological periodontal treatment with and without low-level laser therapy on IL-1β level in gingival crevicular fluid: an in vivo multicentric pilot study.

    Science.gov (United States)

    Mastrangelo, F; Dedola, A; Cattoni, F; Ferrini, F; Bova, F; Tatullo, M; Gherlone, E; Lo Muzio, L

    2018-01-01

    Cytokine proteins may have important roles during different human physiological and pathological processes. In the oral cavity, the bone loss and periodontal tissue pathology was related to inflammatory process activation. The aim of the present study was to assess the effects of etiological periodontal therapy with and without the use of Low Level Laser Therapy (LLLT) on clinical periodontal parameters and interleukin (IL)-1β level in gingival crevicular fluid (GCF) from chronic periodontitis (CP) patients. Thirty non-smoker CP patients were selected from the Foggia University Dental Clinic and other 2 private dental clinics. All patients were divided into two homogeneous randomized groups: 15 patients were treated with only scaling and root planing (group 1) and 15 patients with scaling and root planing etiological treatment and LLLT (group 2). In all sites, at baseline before treatment, the periodontal pocket depth (PPD) and bleeding on probing (BOP) were measured. In the PPD sites, the GCF samples were collected from 30 deep (≥5 mm) and shallow (≤3 mm) sites and IL-1β were evaluated at baseline, after 10 days and 1 month. In all the samples at baseline, the IL-1β concentration in GCF and BOP rate were significantly higher at deep PPD sites than at the shallow ones. After 10 days in all samples no PPD improvement was observed in the BOP rate but the IL-1 β level was statistically significantly improved (pdeep PPD sites, PPD and BOP improvements were observed. At same time, IL-1β levels were lower and statistically significantly (pdeep PPD sites with or with-out associated LLLT promotes periodontal health. Etiological treatment associated with LLLT, improves BOP and inflammation in periodontal disease. Moreover, the IL-1β concentration changes in GCF suggest these cytokines as a predictable marker of gingival inflammation in chronic periodontitis patients.

  13. Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial.

    Science.gov (United States)

    Höfling, Danilo B; Chavantes, Maria Cristina; Juliano, Adriana G; Cerri, Giovanni G; Knobel, Meyer; Yoshimura, Elisabeth M; Chammas, Maria Cristina

    2013-05-01

    Chronic autoimmune thyroiditis (CAT) is the most common cause of acquired hypothyroidism, which requires lifelong levothyroxine replacement therapy. Currently, no effective therapy is available for CAT. Thus, the objective of this study was to evaluate the efficacy of low-level laser therapy (LLLT) in patients with CAT-induced hypothyroidism by testing thyroid function, thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), and ultrasonographic echogenicity. A randomized, placebo-controlled trial with a 9-month follow-up was conducted from 2006 to 2009. Forty-three patients with a history of levothyroxine therapy for CAT-induced hypothyroidism were randomly assigned to receive either 10 sessions of LLLT (830 nm, output power of 50 mW, and fluence of 707 J/cm(2); L group, n=23) or 10 sessions of a placebo treatment (P group, n=20). The levothyroxine was suspended 30 days after the LLLT or placebo procedures. Thyroid function was estimated by the levothyroxine dose required to achieve normal concentrations of T3, T4, free-T4 (fT4), and thyrotropin after 9 months of postlevothyroxine withdrawal. Autoimmunity was assessed by measuring the TPOAb and TgAb levels. A quantitative computerized echogenicity analysis was performed pre- and 30 days postintervention. The results showed a significant difference in the mean levothyroxine dose required to treat the hypothyroidism between the L group (38.59 ± 20.22 μg/day) and the P group (106.88 ± 22.90 μg/day, Phypothyroidism.

  14. Effects of low-level laser therapy applied before or after plyometric exercise on muscle damage markers: randomized, double-blind, placebo-controlled trial.

    Science.gov (United States)

    Fritsch, Carolina Gassen; Dornelles, Maurício Pinto; Severo-Silveira, Lucas; Marques, Vanessa Bernardes; Rosso, Isabele de Albuquerque; Baroni, Bruno Manfredini

    2016-12-01

    Promising effects of phototherapy on markers of exercise-induced muscle damage has been already demonstrated in constant load or isokinetic protocols. However, its effects on more functional situations, such as plyometric exercises, and when is the best moment to apply this treatment (pre- or post-exercise) remain unclear. Therefore, the purpose of this study was to investigate the effect of low-level laser therapy (LLLT) before or after plyometric exercise on quadriceps muscle damage markers. A randomized, double-blinded, placebo-controlled trial was conducted with 24 healthy men, 12 at pre-exercise treatment group and 12 at post-exercise treatment group. Placebo and LLLT (810 nm, 200 mW per diode, 6 J per diode, 240 J per leg) were randomly applied on right/left knee extensor muscles of each volunteer before/after a plyometric exercise protocol. Muscular echo intensity (ultrasonography images), soreness (visual analogue scale - VAS), and strength impairment (maximal voluntary contraction - MVC) were assessed at baseline, 24, 48, and 72 h post-exercise. Legs treated with LLLT before or after exercise presented significantly smaller increments of echo intensity (values up to 1 %) compared to placebo treatments (increased up to ∼7 %). No significant treatment effect was found for VAS and MVC, although a trend toward better results on LLLT legs have been found for VAS (mean values up to 30 % lesser than placebo leg). In conclusion, LLLT applied before or after plyometric exercise reduces the muscle echo intensity response and possibly attenuates the muscle soreness. However, these positive results were not observed on strength impairment.

  15. Evaluation of low-level laser therapy, platelet-rich plasma, and their combination on the healing of Achilles tendon in rabbits.

    Science.gov (United States)

    Allahverdi, Amin; Sharifi, Davood; Takhtfooladi, Mohammad Ashrafzadeh; Hesaraki, Saeed; Khansari, Mohammadreza; Dorbeh, Shahab Sarrout

    2015-05-01

    Tendon repair is still one of the challenges for rehabilitation. Various treatments for tendon injuries have been used in recent decade. This study was established to investigate the effects of low-level laser therapy (LLLT), platelet-rich plasma (PRP) treatment alone, and using combined method on the healing of Achilles tendon in rabbits. Seventy-two healthy mature male white New Zealand rabbits were divided randomly into four groups of 18 animals each: control: partial tenotomy with no treatment, only 1 mL normal saline was injected on days 1, 8, and 15 at the site of splitting; PRP: partial tenotomy with PRP treatment on days 1, 8, and 15 at the site of splitting; LLLT: partial tenotomy with LLLT (K30 hand-held probe, AZOR, Technica, Russia, 650 nm, 30 mW, surface area = 1 cm(2), 60 S/cm(2), energy density = 1.8 J/cm(2)) for 15 consecutive days; LLLT + PRP: partial tenotomy with LLLT + PRP. At the end of trial, the rabbits were euthanatized and tendon specimens were harvested and were submitted for histopathological evaluation, hydroxyproline levels, and biomechanical measurement. The Tukey post hoc test was performed. The results for these parameters showed that PRP or LLLT alone has significant advantages over untreated animals (P  0.05) between the two groups of LLLT and PRP. However, the treatments combining PRP and LLLT showed significant results in comparison of PRP or LLLT alone (P tendon decreases by using the two therapies combined.

  16. Short-term effects of extremely low-frequency pulsed electromagnetic field and pulsed low-level laser therapy on rabbit model of corneal alkali burn.

    Science.gov (United States)

    Rezaei Kanavi, Mozhgan; Tabeie, Faraj; Sahebjam, Farzin; Poursani, Nima; Jahanbakhsh, Nazanin; Paymanpour, Pouya; AfsarAski, Sasha

    2016-04-01

    This study was conducted to investigate the effect of combining extremely low frequency-pulsed electromagnetic field (ELF-PEMF) and low-level laser therapy (LLLT) on alkali-burned rabbit corneas. Fifty alkali-burned corneas of 50 rabbits were categorized into five groups: ELF-PEMF therapy with 2 mT intensity (ELF 2) for 2 h daily; LLLT for 30 min twice daily; combined ELF-PEMF and LLLT (ELF + LLLT); medical therapy (MT); and control (i.e., no treatment). Clinical examination and digital photography of the corneas were performed on days 0, 2, 7, and 14. After euthanizing the rabbits, the affected eyes were evaluated by histopathology. The clinical and histopathologic results were compared between the groups. On days 7 and 14, no significant difference in the corneal defect area was evident between the ELF, LLLT, ELF + LLLT, and MT groups. Excluding the controls, none of the study groups demonstrated a significant corneal neovascularization in both routine histopathology and immunohistochemistry for CD31. Keratocyte loss was significantly higher in the MT group than in the ELF, LLLT, and ELF + LLLT groups. Moderate to severe stromal inflammation in the LLLT group was comparable with that in the MT group and was significantly lower than that in the other groups. In conclusion, combining LLLT and ELF was not superior to ELF alone or LLLT alone in healing corneal alkali burns. However, given the lower intensity of corneal inflammation and the lower rate of keratocytes loss with LLLT, this treatment may be superior to other proposed treatment modalities for healing alkali-burned corneas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Effect of low-level laser therapy on pain, quality of life and sleep in patients with fibromyalgia: study protocol for a double-blinded randomized controlled trial.

    Science.gov (United States)

    de Carvalho, Paulo de Tarso Camillo; Leal-Junior, Ernesto Cesar Pinto; Alves, Ana Carolina Araruna; Rambo, Caroline Sobral de Melo; Sampaio, Luciana Maria Malosa; Oliveira, Claudia Santos; Albertini, Regiane; de Oliveira, Luis Vicente Franco

    2012-11-21

    Low-level laser therapy (LLLT) has been widely used as adjuvant strategy for treatment of musculoskeletal disorders. The light-tissue interaction (photobiostimulation) promotes analgesic and anti-inflammatory effects and improves tissue healing, which could justify the recommendation of this therapy for patients with fibromyalgia, leading to an improvement in pain and possibly minimizing social impact related to this disease. The present study proposes to evaluate the effect of LLLT on tender points in patients with fibromyalgia, correlating this outcome with quality of life and sleep. One hundred and twenty patients with fibromyalgia will be treated at the Integrated Health Center and the Sleep Laboratory of the Post Graduate Program in Rehabilitation Sciences of the Nove de Julho University located in the city of Sao Paulo, Brazil. After fulfilling the eligibility criteria, a clinical evaluation and assessments of pain and sleep quality will be carried out and self-administered quality of life questionnaires will be applied. The 120 volunteers will be randomly allocated to an intervention group (LLLT, n = 60) or control group (CLLLT, n = 60). Patients from both groups will be treated three times per week for four weeks, totaling twelve sessions. However, only the LLLT group will receive an energy dose of 6 J per tender point. A standardized 50-minute exercise program will be performed after the laser application. The patients will be evaluated regarding the primary outcome (pain) using the following instruments: visual analog scale, McGill Pain Questionnaire and pressure algometry. The secondary outcome (quality of life and sleep) will be assessed with the following instruments: Medical Outcomes Study 36-item Short-Form Health Survey, Fibromyalgia Impact Questionnaire, Berlin Questionnaire, Epworth Sleepiness Scale and polysomnography. ANOVA test with repeated measurements for the time factor will be performed to test between-groups differences (followed by the

  18. Development of a multichannel RF field detector for the low-level RF control of the free-electron laser at Hamburg

    International Nuclear Information System (INIS)

    Hoffmann, Matthias

    2008-10-01

    Modern free electron lasers produce synchrotron radiation with constantly shortening wavelengths of up to 6 nm and pulse widths of up to 100 fs. That requires a constantly increasing stability of the beam energy and arrival time of the electron beam at the undulator entrance which is situated at the end of the accelerator. At the same time, the increasing speed of digital signal processing and data acquisition facilitates new possibilities for the digital radio frequency control and field detection. In this thesis the development of a multichannel radio frequency field detector for the low level radio frequency (LLRF) control of the superconducting cavities of the Free-Electron Laser at Hamburg (FLASH) is described. The applied method of IF sampling is state of the technology and is utilized in many areas of digital communication. It is evaluated concerning its applicability for the LLRF control. Analytical and numerical investigations of the noise behavior and transport in the control loop have been accomplished to define the requirements for the measurement accuracy of the field detector that was to be developed. Therefore, simplified models of the noise behavior of each system component of the control loop, e.g. amplifier, radio frequency mixer and analog-to-digital converter, were established and subsequently assorted to a the model of the control loop. Due to the application of the vector-sum control, where several separately measured field vectors are added to a vector-sum, requirements concerning the allowable compression error of the detector nonlinearity were defined. These were investigated by analytical and numerical methods, as well. Requirements for the hardware that was to be developed were compiled from the simulation results. For the development of the field detector, a modular and EMC-compatible concept with a high-level passive front-end for an improvement of the signal-to-noise ratio was chosen. The following tests in the lab delivered the

  19. Development of a multichannel RF field detector for the low-level RF control of the free-electron laser at Hamburg

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Matthias

    2008-10-15

    Modern free electron lasers produce synchrotron radiation with constantly shortening wavelengths of up to 6 nm and pulse widths of up to 100 fs. That requires a constantly increasing stability of the beam energy and arrival time of the electron beam at the undulator entrance which is situated at the end of the accelerator. At the same time, the increasing speed of digital signal processing and data acquisition facilitates new possibilities for the digital radio frequency control and field detection. In this thesis the development of a multichannel radio frequency field detector for the low level radio frequency (LLRF) control of the superconducting cavities of the Free-Electron Laser at Hamburg (FLASH) is described. The applied method of IF sampling is state of the technology and is utilized in many areas of digital communication. It is evaluated concerning its applicability for the LLRF control. Analytical and numerical investigations of the noise behavior and transport in the control loop have been accomplished to define the requirements for the measurement accuracy of the field detector that was to be developed. Therefore, simplified models of the noise behavior of each system component of the control loop, e.g. amplifier, radio frequency mixer and analog-to-digital converter, were established and subsequently assorted to a the model of the control loop. Due to the application of the vector-sum control, where several separately measured field vectors are added to a vector-sum, requirements concerning the allowable compression error of the detector nonlinearity were defined. These were investigated by analytical and numerical methods, as well. Requirements for the hardware that was to be developed were compiled from the simulation results. For the development of the field detector, a modular and EMC-compatible concept with a high-level passive front-end for an improvement of the signal-to-noise ratio was chosen. The following tests in the lab delivered the

  20. Oral Mucositis Prevention By Low-Level Laser Therapy in Head-and-Neck Cancer Patients Undergoing Concurrent Chemoradiotherapy: A Phase III Randomized Study

    International Nuclear Information System (INIS)

    Gouvêa de Lima, Aline; Villar, Rosângela Correa; Castro, Gilberto de; Antequera, Reynaldo; Gil, Erlon; Rosalmeida, Mauro Cabral; Federico, Miriam Hatsue Honda; Snitcovsky, Igor Moisés Longo

    2012-01-01

    Purpose: Oral mucositis is a major complication of concurrent chemoradiotherapy (CRT) in head-and-neck cancer patients. Low-level laser (LLL) therapy is a promising preventive therapy. We aimed to evaluate the efficacy of LLL therapy to decrease severe oral mucositis and its effect on RT interruptions. Methods and Materials: In the present randomized, double-blind, Phase III study, patients received either gallium-aluminum-arsenide LLL therapy 2.5 J/cm 2 or placebo laser, before each radiation fraction. Eligible patients had to have been diagnosed with squamous cell carcinoma or undifferentiated carcinoma of the oral cavity, pharynx, larynx, or metastases to the neck with an unknown primary site. They were treated with adjuvant or definitive CRT, consisting of conventional RT 60–70 Gy (range, 1.8–2.0 Gy/d, 5 times/wk) and concurrent cisplatin. The primary endpoints were the oral mucositis severity in Weeks 2, 4, and 6 and the number of RT interruptions because of mucositis. The secondary endpoints included patient-reported pain scores. To detect a decrease in the incidence of Grade 3 or 4 oral mucositis from 80% to 50%, we planned to enroll 74 patients. Results: A total of 75 patients were included, and 37 patients received preventive LLL therapy. The mean delivered radiation dose was greater in the patients treated with LLL (69.4 vs. 67.9 Gy, p = .03). During CRT, the number of patients diagnosed with Grade 3 or 4 oral mucositis treated with LLL vs. placebo was 4 vs. 5 (Week 2, p = 1.0), 4 vs. 12 (Week 4, p = .08), and 8 vs. 9 (Week 6, p = 1.0), respectively. More of the patients treated with placebo had RT interruptions because of mucositis (6 vs. 0, p = .02). No difference was detected between the treatment arms in the incidence of severe pain. Conclusions: LLL therapy was not effective in reducing severe oral mucositis, although a marginal benefit could not be excluded. It reduced RT interruptions in these head-and-neck cancer patients, which might

  1. Oral Mucositis Prevention By Low-Level Laser Therapy in Head-and-Neck Cancer Patients Undergoing Concurrent Chemoradiotherapy: A Phase III Randomized Study

    Energy Technology Data Exchange (ETDEWEB)

    Gouvea de Lima, Aline [Departamento de Radiologia, Disciplina de Oncologia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, SP (Brazil); Villar, Rosangela Correa [Instituto de Radiologia, Servico de Radioterapia, Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, SP (Brazil); Castro, Gilberto de, E-mail: gilberto.castro@usp.br [Department of Clinical Oncology, Instituto do Cancer do Estado de Sao Paulo, Sao Paulo, SP (Brazil); Antequera, Reynaldo [Divisao de Odontologia, Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, SP (Brazil); Gil, Erlon; Rosalmeida, Mauro Cabral [Instituto de Radiologia, Servico de Radioterapia, Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, SP (Brazil); Federico, Miriam Hatsue Honda; Snitcovsky, Igor Moises Longo [Departamento de Radiologia, Disciplina de Oncologia, Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, SP (Brazil)

    2012-01-01

    Purpose: Oral mucositis is a major complication of concurrent chemoradiotherapy (CRT) in head-and-neck cancer patients. Low-level laser (LLL) therapy is a promising preventive therapy. We aimed to evaluate the efficacy of LLL therapy to decrease severe oral mucositis and its effect on RT interruptions. Methods and Materials: In the present randomized, double-blind, Phase III study, patients received either gallium-aluminum-arsenide LLL therapy 2.5 J/cm{sup 2} or placebo laser, before each radiation fraction. Eligible patients had to have been diagnosed with squamous cell carcinoma or undifferentiated carcinoma of the oral cavity, pharynx, larynx, or metastases to the neck with an unknown primary site. They were treated with adjuvant or definitive CRT, consisting of conventional RT 60-70 Gy (range, 1.8-2.0 Gy/d, 5 times/wk) and concurrent cisplatin. The primary endpoints were the oral mucositis severity in Weeks 2, 4, and 6 and the number of RT interruptions because of mucositis. The secondary endpoints included patient-reported pain scores. To detect a decrease in the incidence of Grade 3 or 4 oral mucositis from 80% to 50%, we planned to enroll 74 patients. Results: A total of 75 patients were included, and 37 patients received preventive LLL therapy. The mean delivered radiation dose was greater in the patients treated with LLL (69.4 vs. 67.9 Gy, p = .03). During CRT, the number of patients diagnosed with Grade 3 or 4 oral mucositis treated with LLL vs. placebo was 4 vs. 5 (Week 2, p = 1.0), 4 vs. 12 (Week 4, p = .08), and 8 vs. 9 (Week 6, p = 1.0), respectively. More of the patients treated with placebo had RT interruptions because of mucositis (6 vs. 0, p = .02). No difference was detected between the treatment arms in the incidence of severe pain. Conclusions: LLL therapy was not effective in reducing severe oral mucositis, although a marginal benefit could not be excluded. It reduced RT interruptions in these head-and-neck cancer patients, which might

  2. Low-level x-irradiation of the brain during development morphological, physiological, and behavioral consequences. Final report, September 1, 1976--August 31, 1977

    International Nuclear Information System (INIS)

    Altman, J.

    1977-01-01

    Morphological research was continued in the following areas: glial recovery patterns in the rat corpus callosum after x-irradiation during infancy; the prenatal development of the deep nuclei and cortex of the cerebellum; the prenatal development of the inferior olive, pontine gray and the precerebellar reticular nuclei; and the postnatal development of the olfactory bulb. In these studies autoradiography and x-irradiation were among the experimental techniques utilized. The behavioral studies, all of which are still in progress, are concerned with the effects of different schedules of postnatal x-irradiation of the cerebellum, and the effects of x-irradiation of the olfactory bulb. A list is included of 14 publications that report results in detail

  3. Low level waste disposal

    International Nuclear Information System (INIS)

    Barthoux, A.

    1985-01-01

    Final disposal of low level wastes has been carried out for 15 years on the shallow land disposal of the Manche in the north west of France. Final participant in the nuclear energy cycle, ANDRA has set up a new waste management system from the production center (organization of the waste collection) to the disposal site including the setting up of a transport network, the development of assessment, additional conditioning, interim storage, the management of the disposal center, records of the location and characteristics of the disposed wastes, site selection surveys for future disposals and a public information Department. 80 000 waste packages representing a volume of 20 000 m 3 are thus managed and disposed of each year on the shallow land disposal. The disposal of low level wastes is carried out according to their category and activity level: - in tumuli for very low level wastes, - in monoliths, a concrete structure, of the packaging does not provide enough protection against radioactivity [fr

  4. Low level laser therapy/photobiomodulation in the management of side effects of chemoradiation therapy in head and neck cancer: part 1: mechanisms of action, dosimetric, and safety considerations

    NARCIS (Netherlands)

    Zecha, Judith A. E. M.; Raber-Durlacher, Judith E.; Nair, Raj G.; Epstein, Joel B.; Sonis, Stephen T.; Elad, Sharon; Hamblin, Michael R.; Barasch, Andrei; Migliorati, Cesar A.; Milstein, Dan M. J.; Genot, Marie-Thérèse; Lansaat, Liset; van der Brink, Ron; Arnabat-Dominguez, Josep; van der Molen, Lisette; Jacobi, Irene; van Diessen, Judi; de Lange, Jan; Smeele, Ludi E.; Schubert, Mark M.; Bensadoun, René-Jean

    2016-01-01

    There is a large body of evidence supporting the efficacy of low level laser therapy (LLLT), more recently termed photobiomodulation (PBM), for the management of oral mucositis (OM) in patients undergoing radiotherapy for head and neck cancer (HNC). Recent advances in PBM technology, together with a

  5. Femtosecond laser irradiation-induced infrared absorption on silicon surfaces

    Directory of Open Access Journals (Sweden)

    Qinghua Zhu

    2015-04-01

    Full Text Available The near-infrared (NIR absorption below band gap energy of crystalline silicon is significantly increased after the silicon is irradiated with femtosecond laser pulses at a simple experimental condition. The absorption increase in the NIR range primarily depends on the femtosecond laser pulse energy, pulse number, and pulse duration. The Raman spectroscopy analysis shows that after the laser irradiation, the silicon surface consists of silicon nanostructure and amorphous silicon. The femtosecond laser irradiation leads to the formation of a composite of nanocrystalline, amorphous, and the crystal silicon substrate surface with microstructures. The composite has an optical absorption enhancement at visible wavelengths as well as at NIR wavelength. The composite may be useful for an NIR detector, for example, for gas sensing because of its large surface area.

  6. Biochemical and topological analysis of bovine sperm cells induced by low power laser irradiation

    Science.gov (United States)

    Dreyer, T. R.; Siqueira, A. F. P.; Magrini, T. D.; Fiorito, P. A.; Assumpção, M. E. O. A.; Nichi, M.; Martinho, H. S.; Milazzotto, M. P.

    2011-07-01

    Low-level laser irradiation (LLLI) increases ATP production and energy supply to the cell which could increase sperm motility, acrossomal reaction and consequently the fertilizing potential. The aim of this study was to characterize the biochemical and topological changes induced by low power laser irradiation on bull sperm cells. Post-thawing sperm were irradiated with a 633nm laser with fluence rates of 30, 150 and 300mJ.cm-2 (power of 5mW for 1, 5 and 10minutes, respectively); 45, 230, and 450mJ.cm-2 (7.5mW for 1, 5 and 10 minutes); and 60, 300 and 600mJ.cm-2 (10mW for 1, 5 and 10 minutes). Biochemical and metabolical changes were analyzed by FTIR and flow cytometry; oxygen reactive species production was assessed by TBARS and the morphological changes were evaluated by AFM. Motility had no difference among times or powers of irradiation. Increasing in ROS generation was observed with power of 5mW compared to 7.5 and 10mW, and with 10min of irradiation in comparison with 5 and 1min of irradiation. This higher ROS generation was related to an increase in acrossomal and plasma membrane damage. FTIR results showed that the amount of lipids was inversely proportional to the quantity of ROS generated. AFM images showed morphological differences in plasma/acrossomal membrane, mainly on the equatorial region. We conclude that LLLI is an effective method to induce changes on sperm cell metabolism but more studies are necessary to establish an optimal dose to increase the fertility potential of these cells.

  7. Efficacy of pre-exercise low-level laser therapy on isokinetic muscle performance in individuals with type 2 diabetes mellitus: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Gomes, Cid André Fidelis de Paula; Leal-Junior, Ernesto Cesar Pinto; Biasotto-Gonzalez, Daniela Aparecida; El-Hage, Yasmin; Politti, Fabiano; Gonzalez, Tabajara de Oliveira; Dibai-Filho, Almir Vieira; de Oliveira, Adriano Rodrigues; Frigero, Marcelo; Antonialli, Fernanda Colella; Vanin, Adriane Aver; de Tarso Camillo de Carvalho, Paulo

    2014-04-09

    Type 2 diabetes, also known non-insulin-dependent diabetes, is the most prevalent type of the disease and involves defects in the secretion and action of insulin. The aim of the proposed study is to evaluate the efficacy of pre-exercise low-level laser therapy (LLLT) on muscle performance of the quadriceps femoris in individuals with type 2 diabetes. A double-blind, randomized, controlled clinical trial will be carried out in two treatment phases. In the first phase, quadriceps muscle performance will be evaluated using an isokinetic dynamometer and the levels of creatine kinase and lactate dehydrogenase (biochemical markers of muscle damage) will be determined. The participants will then be allocated to four LLLT groups through a randomization process using opaque envelopes: Group A (4 Joules), Group B (6 Joules), Group C (8 Joules) and Group D (0 Joules; placebo). Following the administration of LLLT, the participants will be submitted to an isokinetic eccentric muscle fatigue protocol involving the quadriceps muscle bilaterally. Muscle performance and biochemical markers of muscle damage will be evaluated again immediately after as well as 24 and 48 hours after the experimental protocol. One week after the last evaluation the second phase will begin, during which Groups A, B and C will receive the LLLT protocol that achieved the best muscle performance in phase 1 for a period of 4 weeks. At the end of this period, muscle performance will be evaluated again. The protocol for this study is registered with the World Health Organization under Universal Trial Number U1111-1146-7109. The purpose of this randomized clinical trial is to evaluate the efficacy of pre-exercise LLLT on the performance of the quadriceps muscle (peak torque, total muscle work, maximum power and fatigue index - normalized by body mass) in individuals with DM-2. The study will support the practice of evidence-based to the use of LLLT in improving muscle performance in Individuals with DM-2

  8. Preconditioning by light-load eccentric exercise is equally effective as low-level laser therapy in attenuating exercise-induced muscle damage in collegiate men

    Directory of Open Access Journals (Sweden)

    Nausheen S

    2017-09-01

    Full Text Available Samar Nausheen,1 Jamal Ali Moiz,1 Shahid Raza,1 Mohammad Yakub Shareef,2 Shahnawaz Anwer,3,4 Ahmad H Alghadir3 1Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi, India; 2Faculty of Dentistry, Jamia Millia Islamia, New Delhi, India; 3Rehabilitation Research Chair, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; 4Dr. D. Y. Patil College of Physiotherapy, Dr. D. Y. Patil Vidyapeeth, Pune, India Background/objective: Previous studies have already reported an independent effect of light-load eccentric exercise (10% eccentric exercise contraction [EEC] and low-level laser therapy (LLLT as a protective measure against more strenuous eccentric exercise. However, the difference between these two interventions is largely unknown. Therefore, the present study aimed to compare the preconditioning effect of 10% EEC vs. LLLT on subjective, physiological, and biochemical markers of muscle damage in elbow flexors in collegiate men.Methods: All 36 enrolled subjects were randomly assigned to either 10% EEC or LLLT group. Subjects in 10% EEC group performed 30 repetitions of an eccentric exercise with 10% maximal voluntary contraction strength 2 days prior to maximal eccentric exercise bout, whereas subjects in LLLT group were given LLLT. All the indirect markers of muscle damage were measured pre-exercise and at 24, 48, and 72 hours after the exercise-induced muscle damage protocol.Results: The muscle soreness was reduced in both groups (p = 0.024; however, soreness was attenuated more in LLLT group at 48 hours (33.5 vs. 42.7, p = 0.004. There was no significant difference between the effect of 10% EEC and LLLT groups on other markers of muscle damage like a maximum voluntary isometric contraction (p = 0.47, range of motion (p = 0.16, upper arm circumference (p = 0.70, creatine kinase (p = 0.42, and lactate dehydrogenase (p = 0.08. Within-group analysis showed both interventions provided

  9. Photocatalytic Oxidation of Low-Level Airborne 2-Propanol and Trichloroethylene over Titania Irradiated with Bulb-Type Light-Emitting Diodes.

    Science.gov (United States)

    Jo, Wan-Kuen

    2013-01-18

    This study examined the photocatalytic oxidation of gas-phase trichloroethylene (TCE) and 2-propanol, at indoor levels, over titanium dioxide (TiO₂) irradiated with light-emitting diodes (LED) under different operational conditions. TiO₂ powder baked at 450 °C exhibited the highest photocatalytic decomposition efficiency (PDE) for TCE, while all photocatalysts baked at different temperatures showed similar PDEs for 2-propanol. The average PDEs of TCE over a three hour period were four, four, five, and 51% for TiO₂ powders baked at 150, 250, 350, and 450 °C, respectively. The average PDEs of 2-propanol were 95, 97, 98, and 96% for TiO₂ powders baked at 150, 250, 350, and 450 °C, respectively. The ratio of anatase at 2θ = 25.2° to rutile at 2θ = 27.4° was lowest for the TiO₂ powder baked at 450 °C. Although the LED-irradiated TiO₂ system revealed lower PDEs of TCE and 2-propanol when compared to those of the eight watt, black-light lamp-irradiated TiO₂ system, the results for the PDEs normalized to the energy consumption were reversed. Other operational parameters, such as relative humidity, input concentrations, flow rate, and feeding type were also found to influence the photocatalytic performance of the UV LED-irradiated TiO₂ system when applied to the cleaning of TCE and 2-propanol at indoor air levels.

  10. Low-level x-irradiation of the brain during development: morphological, physiological, and behavioral consequences. Progress report, September 1, 1974--August 31, 1975

    International Nuclear Information System (INIS)

    Altman, J.

    1975-01-01

    Progress is reported on studies on the effects of exposure to low-dose x radiation on the developing brain of rats. Brief summaries of results of morphological, physiological, and behavioral studies on rats exposed using various x-irradiation schedules are included. A list of papers published and submitted for publication during the period is included. (U.S.)

  11. Communication: Mode bifurcation of droplet motion under stationary laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Takabatake, Fumi [Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Department of Bioengineering and Robotics, Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8579 (Japan); Yoshikawa, Kenichi [Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394 (Japan); Ichikawa, Masatoshi, E-mail: ichi@scphys.kyoto-u.ac.jp [Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan)

    2014-08-07

    The self-propelled motion of a mm-sized oil droplet floating on water, induced by a local temperature gradient generated by CW laser irradiation is reported. The circular droplet exhibits two types of regular periodic motion, reciprocal and circular, around the laser spot under suitable laser power. With an increase in laser power, a mode bifurcation from rectilinear reciprocal motion to circular motion is caused. The essential aspects of this mode bifurcation are discussed in terms of spontaneous symmetry-breaking under temperature-induced interfacial instability, and are theoretically reproduced with simple coupled differential equations.

  12. Spatially resolved nanostructural transformation in graphite under femtosecond laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Marcu, A., E-mail: aurelian.marcu@inflpr.ro [National Institute for Laser, Plasma and Radiation Physics, 077125 Bucharest (Romania); Avotina, L. [Institute of Chemical Physics, University of Latvia, Kronvalda 4, LV 1010 Riga (Latvia); Porosnicu, C. [National Institute for Laser, Plasma and Radiation Physics, 077125 Bucharest (Romania); Marin, A. [Ilie Murgulescu” Institute of Physical Chemistry, 202 Splaiul Independentei 060021, Bucharest (Romania); Grigorescu, C.E.A. [National Institute R& D for Optoelectronics INOE 2000, 077125 Bucharest (Romania); Ursescu, D. [National Institute for Laser, Plasma and Radiation Physics, 077125 Bucharest (Romania); Lungu, M. [National Institute of Materials Physics Atomistilor Str., 105 bis, 077125, Magurele (Romania); Demitri, N. [Hard X-ray Beamline and Structural Biology, Elettra-Sincrotrone Trieste, Strada Statale 14 - km 163,5 in AREA Science Park, 34149 Basovizza TS Italy (Italy); Lungu, C.P. [National Institute for Laser, Plasma and Radiation Physics, 077125 Bucharest (Romania)

    2015-11-15

    Graphical abstract: - Highlights: • Polycrystalline graphite was irradiated with a high power fs (IR) laser. • Presence of a diamond peak was detected by synchrotron XRD. • XPS and Raman showed in-depth sp{sup 3}% increase at tens of nm below the surface. • sp{sup 3}% is increasing with laser power density but it is independent of photon absorption rate. • Graphite crystallite size locally increase at tens of nanometers below the irradiated spots. - Abstract: A polycrystalline graphite target was irradiated using infrared (800 nm) femtosecond (120 fs) laser pulses of different energies. Increase of sp{sup 3} bonds percentage and possible diamond crystal formation were investigated ‘in-depth’ and on the irradiated surfaces. Synchrotron X-ray diffraction pattern have shown the presence of a diamond peak in one of the irradiated zones while X-ray photoelectron spectroscopy investigations have shown an increasing tendency of the sp{sup 3} percent in the low power irradiated areas and similarly ‘in the depth’ of the higher power irradiated zones. Multiple wavelength Micro-Raman investigations have confirmed this trend along with an ‘in-depth’ (but not on the surface) increase of the crystallite size. Based on the wavelength dependent photon absorption into graphite, the observed effects are correlated with high density photon per atom and attributed to the melting and recrystallization processes taking place tens of nanometers below the target surface.

  13. Spatially resolved nanostructural transformation in graphite under femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Marcu, A.; Avotina, L.; Porosnicu, C.; Marin, A.; Grigorescu, C.E.A.; Ursescu, D.; Lungu, M.; Demitri, N.; Lungu, C.P.

    2015-01-01

    Graphical abstract: - Highlights: • Polycrystalline graphite was irradiated with a high power fs (IR) laser. • Presence of a diamond peak was detected by synchrotron XRD. • XPS and Raman showed in-depth sp 3 % increase at tens of nm below the surface. • sp 3 % is increasing with laser power density but it is independent of photon absorption rate. • Graphite crystallite size locally increase at tens of nanometers below the irradiated spots. - Abstract: A polycrystalline graphite target was irradiated using infrared (800 nm) femtosecond (120 fs) laser pulses of different energies. Increase of sp 3 bonds percentage and possible diamond crystal formation were investigated ‘in-depth’ and on the irradiated surfaces. Synchrotron X-ray diffraction pattern have shown the presence of a diamond peak in one of the irradiated zones while X-ray photoelectron spectroscopy investigations have shown an increasing tendency of the sp 3 percent in the low power irradiated areas and similarly ‘in the depth’ of the higher power irradiated zones. Multiple wavelength Micro-Raman investigations have confirmed this trend along with an ‘in-depth’ (but not on the surface) increase of the crystallite size. Based on the wavelength dependent photon absorption into graphite, the observed effects are correlated with high density photon per atom and attributed to the melting and recrystallization processes taking place tens of nanometers below the target surface.

  14. Photocatalytic Oxidation of Low-Level Airborne 2-Propanol and Trichloroethylene over Titania Irradiated with Bulb-Type Light-Emitting Diodes

    Directory of Open Access Journals (Sweden)

    Wan-Kuen Jo

    2013-01-01

    Full Text Available This study examined the photocatalytic oxidation of gas-phase trichloroethylene (TCE and 2-propanol, at indoor levels, over titanium dioxide (TiO2 irradiated with light-emitting diodes (LED under different operational conditions. TiO2 powder baked at 450 °C exhibited the highest photocatalytic decomposition efficiency (PDE for TCE, while all photocatalysts baked at different temperatures showed similar PDEs for 2-propanol. The average PDEs of TCE over a three hour period were four, four, five, and 51% for TiO2 powders baked at 150, 250, 350, and 450 °C, respectively. The average PDEs of 2-propanol were 95, 97, 98, and 96% for TiO2 powders baked at 150, 250, 350, and 450 °C, respectively. The ratio of anatase at 2θ = 25.2° to rutile at 2θ = 27.4° was lowest for the TiO2 powder baked at 450 °C. Although the LED-irradiated TiO2 system revealed lower PDEs of TCE and 2-propanol when compared to those of the eight watt, black-light lamp-irradiated TiO2 system, the results for the PDEs normalized to the energy consumption were reversed. Other operational parameters, such as relative humidity, input concentrations, flow rate, and feeding type were also found to influence the photocatalytic performance of the UV LED-irradiated TiO2 system when applied to the cleaning of TCE and 2-propanol at indoor air levels.

  15. Improvement of laser irradiation uniformity in GEKKO XII glass laser system

    International Nuclear Information System (INIS)

    Miyanaga, Noriaki; Matsuoka, Shinichi; Ando, Akinobu; Amano, Shinji; Nakatsuka, Masahiro; Kanabe, Tadashi; Jitsuno, Takahisa; Nakai, Sadao

    1995-01-01

    The uniform laser irradiation is one of key issues in the direct drive laser fusion research. The several key technologies for the uniform laser irradiation are reported. This paper includes the uniformity performance as a result of the introduction of the random phase plate, the partially coherent light and the beam smoothing by spectral dispersion into the New Gekko XI glass laser system. Finally the authors summarize the overall irradiation uniformity on the spherical target surface by considering the power imbalance effect. The technologies developed for the beam smoothing and the power balance control enable them to achieve the irradiation nonuniformities of around 1% level for a foot pulse and of a few % for a main drive pulse, respectively

  16. Influence of powerful pulses of laser irradiation on metallic films

    International Nuclear Information System (INIS)

    Besogonov, V.V.; Chudinov, V.G.

    1999-01-01

    The relaxation process of energy transferred by powerful pulses of laser irradiation to a superficial layer in metallic films has been investigated by the molecular dynamics technique. Beam energy transformation into mechanical energy of movement of irradiated atoms is shown to be possible due to changing pair interaction potentials. Variation of the Coulomb interaction screening of an ionic subsystem through the excitation of valence electrons is illustrated as major of the reasons for changing the potentials

  17. Morphological changes in skin tumors caused by pulsed laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Moskalik, K G; Lipova, V A; Neyshtadt, E L

    1979-01-01

    Morphological changes induced by treating melanomas, basaloma and flatcell skin cancers with a pulsed neodymium laser at 1060 nm, pulse length 1 msec and energy 250 to 500 J/cm/sup 2/, were studied using impressions and scrapings from the affected area. Nuclear pyknosis, nuclear and cellular elongation, vacuolization, frequent complete loss of cytoplasm, particulaly in the zone of direct irradiation, and loss of cellular structure were seen. These dystrophic changes increased with closeness to the zone of direct irradiation, culminating in necrosis. Formed and decomposed blood elements and melanin accumulated in the intracellular spaces, due to disruption of capillaries and small arteries and veins. Fewer and more aggregated melanoblasts were found after melanoma irradiation. Nuclear chromatin fusion, cytoplasmic changes and altered cell shape were observed. Basaloma cells were clustered and elongated after irradiation, with many fibrous structures and loss of cellular elements. Cytoplasmic vacuolization and lysis, bare nuclei, karyolysis, karyorrhexis and karyopyknosis were seen in corneous flat-cell cancer. In the few cases in which malignant cells were found under the scab from the first treatment the procedure was repeated. The morphological changes induced by pulsed laser irradiation are very similar to electrocoagulation necrosis, but are more localized. The ability of low and middle energy lasers to induce thrombosis and coagulation in vascular walls reduced the probability of hematogenic tumor cell dissemination. Cytological examination is highly effective in determining the degree of radical skin cancer healing due to laser treatment. 12 references, 2 figures.

  18. Closure phenomena in pinholes irradiated by Nd laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Auerbach, J.M.; Holmes, N.C.; Hunt, J.T.; Linford, G.J.

    1979-07-15

    An experimental investigation has been made on plasma closure in pinholes irradiated by Nd glass laser pulses; 300--500-..mu..m diam pinholes of various materials and thicknesses have been irradiated by 20--100-J 300-psec FWHM pulses on the Janus laser system. Calorimetry measurements have yielded data on pinhole energy transmission and intensity loading on the periphery of the pinhole. Ultrafast streak photography measurements indicate effective closure velocities of 2--5 x 10/sup 7/ cm/sec. Scattered light measurements have shown the transmission loss through a typical spatial filter configuration to be primarily refractive in nature.

  19. Pulse laser irradiation into superconducting MgB2 detector

    International Nuclear Information System (INIS)

    Fujiwara, Daisuke; Miki, Shigehito; Satoh, Kazuo; Yotsuya, Tsutomu; Shimakage, Hisashi; Wang, Zhen; Okayasu, Satoru; Katagiri, Masaki; Machida, Masahiko; Kato, Masaru; Ishida, Takekazu

    2005-01-01

    We performed 20-ps pulse laser irradiation experiments on a MgB 2 neutron detector to know a thermal-relaxation process for designing a MgB 2 neutron detector. The membrane-type structured MgB 2 device was fabricated to minimize the heat capacity of sensing part of a detector as well as to enhance its sensitivity. We successfully observed a thermal-relaxation signal resulting from pulse laser irradiation by developing a detection circuit. The response time was faster than 1 μs, meaning that the detector would be capable of counting neutrons at a rate of more than 10 6 events per second

  20. Laser effects on graphene oxide irradiated in high vacuum

    Czech Academy of Sciences Publication Activity Database

    Torrisi, L.; Silipigni, L.; Cutroneo, Mariapompea

    2018-01-01

    Roč. 173, 1-2 (2018), s. 73-84 ISSN 1042-0150 R&D Projects: GA MŠk LM2015056; GA ČR GA16-05167S Institutional support: RVO:61389005 Keywords : graphene oxide * laser irradiation * laser-generated plasma * radiation effects Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 0.443, year: 2016

  1. Low-level effects

    International Nuclear Information System (INIS)

    Devine, R.T.; Chaput, R.L.

    1987-01-01

    Risk assignments can be made to given practices involving exposure to radiation, because sufficient data are available for the effects of high-dose, low-LET radiation and because sufficient exists in the methods of extrapolation to low doses and low dose rates. The confidence in the extrapolations is based on the fact that the risk is not expected to be overestimated, using the assumptions made (as opposed to the possibility that the extrapolations represent an accurate estimate of the risk). These risk estimates have been applied to the selection of permissible exposure levels, to show that various amounts of radiation involve no greater risk to the worker than the risk expected in another industry that is generally considered safe. The setting of standards for protection from exposure to low levels of ionizing radiation is made by expert committees at the national and international levels who weigh social factors as well as scientific factors. Data on low-level effects may be applied when assigning a ''probability of causation'' to a certain exposure of radiation. This has become a prominent method for arriving at an equitable award for damages caused by such exposure. The generation of these tables requires as many (if not more) social and political considerations as does the setting up of protection criteria. It is impossible to extract a purely scientific conclusion solely from the protection standards and other legal decisions. Sufficient information exists on low-LET radiation that safety standards for exposure can be rationally (if not scientifically) agreed upon

  2. Effects of low-level (1.0 R) x-irradiation on the erythroid response of the rat bone marrow

    International Nuclear Information System (INIS)

    Gong, J.K.; Glomski, C.A.; Frederiksen, N.L.; Lawson, A.J.; Daley, J.P.

    1976-01-01

    The levels of normoblasts in the bone marrow of six groups of female Sprague--Dawley rats previously exposed to a 1.0 R dose of x rays were compared with those in sham-exposed animals at intervals from 14 hr to 10 weeks postirradiation. Four parameters were analyzed, the percentage of normoblasts in Wright's Giemsa stained marrow smears, and the number of erythroid precursors per milligram of isolated marrow sample, per whole femur, and per entire skeleton. The studies were based on marrow examinations and on 59 Fe tracer data. At all intervals except the earliest, [14 hr], significant elevations in the percentage of normoblasts were found in the bone marrow. In addition, at 6 and 10 weeks postirradiation increases were found in the number of normoblasts in the isolated marrow samples, whole femurs, and total skeletons. When compared 81 hr after phlebotomy, subnormal increases in normoblast levels were found in all four parameters of the irradiated subjects. The results suggest that x irradiation at this dose level can induce an abnormal marrow function manifested by an elevated number of normoblasts and, after phlebotomy, by a subnormal proliferation of the erythroid precursors

  3. Towards a laser fluence dependent nanostructuring of thin Au films on Si by nanosecond laser irradiation

    International Nuclear Information System (INIS)

    Ruffino, F.; Pugliara, A.; Carria, E.; Romano, L.; Bongiorno, C.; Fisicaro, G.; La Magna, A.; Spinella, C.; Grimaldi, M.G.

    2012-01-01

    Highlights: ► Au nanoclusters are produced by nanosecond laser irradiations of thin Au film on Si. ► The shape, size, and surface density of the Au nanoclusters are tunable by laser fluence. ► The formation dynamic of the Au nanoclusters under nanosecond laser irradiation is analyzed. - Abstract: In this work, we study the nanostructuring effects of nanosecond laser irradiations on 5 nm thick Au film sputter-deposited on Si. After deposition of Au on Si substrate, nanosecond laser irradiations were performed increasing the laser fluence from 750 to 1500 mJ/cm 2 . Several analyses techniques, such as Rutherford backscattering spectrometry, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy were crossed to study the morphological evolution of the Au film as a function of laser fluence. In particular, the formation of Au nanoparticles was observed. The analyses allowed a quantitative evaluation of the evolution of the nanoparticles size, surface density, and shape as a function of the laser fluence. Therefore, a control the structural properties of the Au nanoparticles is reached, for example, for applications in Si nanowires growth or plasmonics.

  4. Effect of maize seed laser irradiation on plant photosynthetic activity

    International Nuclear Information System (INIS)

    Antonov, M.; Stanev, V.; Velichkov, D.; Tsonev, Ts.

    1986-01-01

    Investigations were made with the two hybrids, H-708 and P x -20. The seeds were irradiated by a helium-neon quantum generator (L'vov-1 Electronica) with output power of 24 MW and 632.8 nm wave length. Once and twice irradiated seeds were sown on the 2nd, 5th and 10th day post irradiation. Changes in leaf area, chlorophyll content in the leaves, photosynthetic rate and its dependence on temperature and light, transpiration, stomatal resistance to CO 2 and total dry matter of the overground plant part were traced. Seed irradiation with laser rays did not affect the chlorophyll content of the leaves. The photosynthetic rate did not depend on the cultivar characteristics of the crop. Single and repeated irradiation of the hybrid H-708 in most case enhanced photosynthetic rate, but a similar effect was not observed in P x -20. Transpiration and CO 2 stomatal resistance were not equally affected by radiation. Laser rays enhanced the ability of the photosynthetic apparatus of the entire plants to use more efficiently high light intensities. The leaf area and the total plant dry matter increased in case of sowing on the 2nd and 5th day and a single irradiation and in case of sowing on the 5th and 10th day and twice repeated irradiations

  5. 弱激光治疗颞下颌关节紊乱病疼痛的研究进展%The research progress of low level laser therapy for temporomandibular disorders pain

    Institute of Scientific and Technical Information of China (English)

    徐高丽; 谷志远; 柳毅

    2015-01-01

    疼痛是颞下颌关节紊乱病患者最常见的临床表现之一,也是大多数人治疗颞下颌关节紊乱病的原因。弱激光在牙科领域的应用越来越广泛,且在颞下颌关节紊乱病治疗中的应用也越来越多,用来抗炎和缓解疼痛。本文对弱激光疗法在治疗颞下颌关节紊乱病疼痛机理方面进行概述。了解弱激光疗法的机制对弱激光治疗颞下颌关节紊乱病具有重要意义。%Pain is a symptom of temporomandibular disorders. It is also the reason for most people to treat temporomandibular disor-ders. Low-level laser is more and more widely applied in the field of dentistry,and is often used in the clinical treatment of temporoman-dibular joint pain for anti-inflammation and pain relief. In this paper,the mechanisms of the low-level laser therapy in treatment of tem-poromandibular disorders pain are summarized. Understanding its mechanism is of great significance for the clinical application of low-level laser in treating temporomandibular disorders.

  6. Optothermal transfer simulation in laser-irradiated human dentin.

    Science.gov (United States)

    Moriyama, Eduardo H; Zangaro, Renato A; Lobo, Paulo D C; Villaverde, Antonio Balbin; Pacheco, Marcos T; Watanabe, Ii-Sei; Vitkin, Alex

    2003-04-01

    Laser technology has been studied as a potential replacement to the conventional dental drill. However, to prevent pulpal cell damage, information related to the safety parameters using high-power lasers in oral mineralized tissues is needed. In this study, the heat distribution profiles at the surface and subsurface regions of human dentine samples irradiated with a Nd:YAG laser were simulated using Crank-Nicolson's finite difference method for different laser energies and pulse durations. Heat distribution throughout the dentin layer, from the external dentin surface to the pulp chamber wall, were calculated in each case, to investigate the details of pulsed laser-hard dental tissue interactions. The results showed that the final temperature at the pulp chamber wall and at the dentin surface are strongly dependent on the pulse duration, exposure time, and the energy contained in each pulse.

  7. Parameter optimization for steel quenching by C02-laser irradiation

    International Nuclear Information System (INIS)

    Moryashchev, S.F.; Kislitsyn, A.A.; Kosyrev, F.K.

    1984-01-01

    The dependence of average absorption factor on maximal temperature of the article surface during quenching by CO 2 -laser irradiation was determined empirically. The calculations of depth of a hardening zone and process productivity in 40 Kh, 4Kh13 steels and Armco-iron with regard to this dependence were conducted

  8. Petawatt laser and target irradiation system at LLNL

    International Nuclear Information System (INIS)

    Pennington, D.M.; Perry, M.D.; Britten, J.A.; Brown, C.G.; Herman, S.; Homer, J.; Miller, J.L.; Stuart, B.C.; Tietbohl, G.; Van Lue, J.; Yanovsky, V.

    1997-01-01

    In May, 1996, we demonstrated the production over a petawatt of peak power in the Nova/Petawatt Laser Facility, generating 620 J in ∼ 430 fs. Results of the first focused irradiance tests, and recent deployment of a novel targeting system will be presented

  9. Regrowth of Si and Ge under laser irradiation

    International Nuclear Information System (INIS)

    Bertolotti, M.; Vitali, G.

    1979-01-01

    The effects of pulsed laser irradiation on amorphous layers of Si and Ge obtained via ion implantation are considered. Amorphous-polycrystalline, amorphous-single crystal and polycrystalline-single crystal transitions have been obtained. Residual disorder and mechanical damage are considered. (author)

  10. Bactericidal effect of Nd:YAG laser irradiation in endodontics

    Science.gov (United States)

    Aun, Carlos E.; Barberini, Alexandre F.; Camargo, Selma C. C.; Silva Kfouri, Luciana; Lorenzetti Simionato, Maria R.

    1999-05-01

    The success of endodontic therapy is based on the elimination of bacterial colonization from the endodontic system and periapical tissues. Recent studies have been showing the bactericidal effect of laser in root canal treatment. The propose of the study is to evaluate the effect of Nd:YAG laser irradiation in contaminated root canal treatment. The propose of the study is to evaluate the effect of Nd:YAG laser irradiation in contaminated root canals from upper central incisor. For the experiment 12 teeth were selected, respect at the apical third, sterilized, and 10 μm Streptococcus sanguis liquid culture were inoculated in the root canals. The laser test groups were irradiated with Nd:YAG laser at standard setting of 15Hz, 100mj and 1,5 W for 10, 20 and 30 seconds each in slow helicoidal movements from the apex to the top using a 300 micrometers fiber. After the procedure the specimens were placed in Tryptic Soy Agar, the number of colony forming units was evaluated. The experiment showed a significant reduction on viability of Streptococcus sanguis at the respective time of 20 and 30 seconds.

  11. Particle velocity measurements in laser irradiated foils using ORVIS

    International Nuclear Information System (INIS)

    Sheffield, S.A.; Fisk, G.A.

    1983-01-01

    Aluminum foils from 2- to 200-μm thick have been subjected to a Nd:YAG laser pulse of low irradiance (10 9 W/cm 2 , approx. 10 ns pulse) to produce laser-driven shocks in the foils. The particle velocity history of the foil side opposite the laser deposition was monitored with nanosecond resolution by a velocity interferometer system called ORVIS. These histories indicate a shock reverberation process accelerates the foil. Peak foil velocities can be adequately calculated using a ricket propulsion model developed from experiments at much higher irradiances. A velocity of 1 km/s was developed in a 2-μm-thick free foil in a time of 50 ns. Water-confined foils attained peak particle velocities about three times higher than those of free foils

  12. Optical-Thermal Response of Laser-Irradiated Tissue

    CERN Document Server

    Welch, Ashley J

    2011-01-01

    The second edition of 'Optical-Thermal Response of Laser-Irradiated Tissue' maintains the standard of excellence established in the first edition, while adjusting the content to reflect changes in tissue optics and medical applications since 1995. The material concerning light propagation now contains new chapters devoted to electromagnetic theory for coherent light. The material concerning thermal laser-tissue interactions contains a new chapter on pulse ablation of tissue. The medical applications section now includes several new chapters on Optical Coherent Tomography, acoustic imaging, molecular imaging, forensic optics and nerve stimulation. A detailed overview is provided of the optical and thermal response of tissue to laser irradiation along with diagnostic and therapeutic examples including fiber optics. Sufficient theory is included in the book so that it is suitable for a one or two semester graduate or for senior elective courses. Material covered includes: 1. light propagation and diagnostic appl...

  13. Low-level radiation

    International Nuclear Information System (INIS)

    Myers, D.K.

    1982-05-01

    It is known that the normal incidence of cancer in human populations is increased by exposure to moderately high doses of ionizing radiation. At background radiation levels or at radiation levels which are 100 times greater, the potential health risks are considered to be directly proportional to the total accumulated dose of radiation. Some of the uncertainties associated with this assumption and with the accepted risk estimates have been critically reviewed in this document. The general scientific consensus at present suggests that the accepted risk estimates may exaggerate the actual risk of low levels of sparsely ionizing radiations (beta-, gamma- or X-rays) somewhat but are unlikely to overestimate the actual risks of densely ionizing radiations (fast neutrons, alpha-particles). At the maximum permissible levels of exposure for radiation workers in nuclear power stations, the potential health hazards in terms of life expectancy would be comparable to those encountered in transportation and public utilities or in the construction industry. At the average radiation exposures received by these workers in practice, the potential health hazards are similar to those associated with safe categories of industries. Uranium mining remains a relativly hazardous occupation. In terms of absolute numbers, the genetic hazards, which are less well established, are thought to be smaller than the carcinogenic hazards of radiation when only the first generation is considered but to be of the same order of magnitude as the carcinogenic hazards when the total number of induced genetic disorders is summed over all generations

  14. Segmental irradiation of the bladder with neodymium YAG laser irradiation

    International Nuclear Information System (INIS)

    McPhee, M.S.; Mador, D.R.; Tulip, J.; Ritchie, B.; Moore, R.; Lakey, W.H.

    1982-01-01

    The Neodymium YAG laser energy source can be readily adapted for cystoscopic use by some simple modifications of existing urologic equipment. Both the fiberoptic resectoscope and a deflecting cystourethroscope have been adapted for this purpose. Fixation of the fiber tip 1 cm. from the target and use of a divergent beam of 36 degrees allows the delivery of standardized dosage to a relatively large bladder tissue volume. Animal experiments involving 35 mongrel dogs established that repetitive overlapping doses of 200 joules ech can successfully treat a large area of bladder resulting in a full thickness bladder wall injury. This technique has been used in 4 high risk patients with infiltrating bladder cancer without adverse sequelae. The ability to reliably produce a full thickness lesion may give this modality a therapeutic advantage over conventional cautery techniques especially for the treatment of residual infiltrative carcinoma

  15. Os efeitos do laser hélio-neônio de baixa intensidade na cicatrização de lesões cutâneas induzidas em ratos Effects of low-level helium-neon laser on induced wound healing in rats

    Directory of Open Access Journals (Sweden)

    Viviane L. Busnardo

    2010-02-01

    Full Text Available OBJETIVO: Avaliar os efeitos do laser de baixa potência hélio e neônio (HeNe na cicatrização de feridas cutâneas de ratos. MÉTODOS: Sessenta ratos Wistar foram divididos em grupos controle e experimento. Utilizou-se ferida incisional, longitudinal, dorso-mediana, suturada com pontos separados simples. No grupo experimento, as feridas foram irradiadas diariamente com aparelho de laser de HeNe com potência contínua máxima de 5mW, comprimento de onda de 632,8 nm, visível com densidade de energia de 4J/cm², área de raio do laser de 0,015cm², durante 36 segundos, em três pontos da lesão. As feridas foram avaliadas no 3º, no 7º e no 14º dia de pós-operatório. Cortes histológicos foram corados com hematoxilina-eosina (H&E e avaliados segundo protocolo de Vizzotto et al. (2003* para identificar o tipo de reação inflamatória e com Picrosirius para identificar os colágenos I e III e o índice de maturidade da cicatriz (IMaC. Utilizou-se imunoistoquímica com anti-CD45-LCA para o reconhecimento das células inflamatórias. RESULTADOS: Ambos os grupos mostraram o mesmo padrão inflamatório. No grupo experimento, observaram-se menos células inflamatórias nos três tempos estudados (pOBJECTIVE: To evaluate the effects of low-level helium-neon (HeNe laser on cutaneous wound healing in rats. METHODS: Sixty Wistar rats were divided into control group and experimental group. A sutured longitudinal, dorsal-medial incision was made, with simple separate stitches. The experimental group was irradiated daily in three areas of the wound with HeNe laser (5mW maximum continuous power, 632.8 nm wavelength, 4 J/cm² energy density and 0.015 cm² laser beam area for 36 seconds. The areas were evaluated on the third, seventh and fourteenth days postoperative. Histological sections were stained with hematoxylin-eosin to determine the type of inflammatory reaction according to the protocol by Vizzotto et al. (2003* and with Picrosirius to identify

  16. A new instrument of VUV laser desorption/ionization mass spectrometry imaging with micrometer spatial resolution and low level of molecular fragmentation.

    Science.gov (United States)

    Wang, Jia; Liu, Feng; Mo, Yuxiang; Wang, Zhaoying; Zhang, Sichun; Zhang, Xinrong

    2017-11-01

    Mass spectrometry imaging (MSI) has important applications in material research, biology, and medicine. The MSI method based on UV laser desorption/ionization (UVLDI) can obtain images of intact samples, but has a high level of molecular fragmentation. In this work, we report a new MSI instrument that uses a VUV laser (125.3 nm) as a desorption/ionization source to exploit its advantages of high single photon energy and small focus size. The new instrument was tested by the mass spectra of Nile red and FGB (Fibrinogen beta chain) samples and mass spectrometric images of a fly brain section. For the tested samples, the VUVDI method offers lower levels of molecular fragmentations and higher sensitivities than those of the UVLDI method and second ion mass spectrometry imaging method using a Bi 3 + beam. The ablation crater produced by the focused VUV laser on a quartz plate has an area of 10 μm 2 . The VUV laser is prepared based on the four-wave mixing method using three collimated laser beams and a heated Hg cell.

  17. A new instrument of VUV laser desorption/ionization mass spectrometry imaging with micrometer spatial resolution and low level of molecular fragmentation

    Science.gov (United States)

    Wang, Jia; Liu, Feng; Mo, Yuxiang; Wang, Zhaoying; Zhang, Sichun; Zhang, Xinrong

    2017-11-01

    Mass spectrometry imaging (MSI) has important applications in material research, biology, and medicine. The MSI method based on UV laser desorption/ionization (UVLDI) can obtain images of intact samples, but has a high level of molecular fragmentation. In this work, we report a new MSI instrument that uses a VUV laser (125.3 nm) as a desorption/ionization source to exploit its advantages of high single photon energy and small focus size. The new instrument was tested by the mass spectra of Nile red and FGB (Fibrinogen beta chain) samples and mass spectrometric images of a fly brain section. For the tested samples, the VUVDI method offers lower levels of molecular fragmentations and higher sensitivities than those of the UVLDI method and second ion mass spectrometry imaging method using a Bi3+ beam. The ablation crater produced by the focused VUV laser on a quartz plate has an area of 10 μm2. The VUV laser is prepared based on the four-wave mixing method using three collimated laser beams and a heated Hg cell.

  18. Physical and Chemical Changes of Polystyrene Nanospheres Irradiated with Laser

    International Nuclear Information System (INIS)

    Mustafa, Mohd Ubaidillah; Juremi, Nor Rashidah Md.; Mohamad, Farizan; Wibawa, Pratama Jujur; Agam, Mohd Arif; Ali, Ahmad Hadi

    2011-01-01

    It has been reported that polymer resist such as PMMA (Poly(methyl methacrylate) which is a well known and commonly used polymer resist for fabrication of electronic devices can show zwitter characteristic due to over exposure to electron beam radiation. Overexposed PMMA tend to changes their molecular structure to either become negative or positive resist corresponded to electron beam irradiation doses. These characteristic was due to crosslinking and scissors of the PMMA molecular structures, but till now the understanding of crosslinking and scissors of the polymer resist molecular structure due to electron beam exposure were still unknown to researchers. Previously we have over exposed polystyrene nanospheres to various radiation sources, such as electron beam, solar radiation and laser, which is another compound that can act as polymer resist. We investigated the physical and chemical structures of the irradiated polystyrene nanospheres with FTIR analysis. It is found that the physical and chemical changes of the irradiated polystyrene were found to be corresponded with the radiation dosages. Later, combining Laser irradiation and Reactive Ion Etching manipulation, created a facile technique that we called as LARIEA NSL (Laser and Reactive Ion Etching Assisted Nanosphere Lithography) which can be a facile technique to fabricate controllable carbonaceous nanoparticles for applications such as lithographic mask, catalysts and heavy metal absorbers.

  19. Biofilms and their modifications by laser irradiation

    International Nuclear Information System (INIS)

    Richter, Asta; Gonpot, Preethee; Smith, Roger

    2001-01-01

    Biofilms are grown on different materials with various surface morphology and are investigated by light and scanning force microscopy. The growth patterns, coverage and adherence of the biofilm are shown to depend on the type of the substrate and its roughness as well as on the type of micro-organisms. Here we present investigations of Eschericia coli bacterial biofilms grown on the polymer material polyetheretherketone and also on titanium films on glass substrates. A Monte Carlo simulation of the growth process is developed which takes into account the aspect ratio of the micro-organisms and the diffusion of nutrient over the surface to feed them. A pulsed nitrogen laser has been applied to the samples and the interaction of the laser beam with the biofilm and the underlying substrate has been studied. Because of the inhomogeneity of the biofilms the ablated areas are different. With increasing number of laser pulses more biofilm material is removed but there appears also damage of the substrate. The threshold energy fluence for the biofilm ablation is estimated and depends on the sticking power of the bacteria. Ablation rates for the removal of the biofilms are also obtained

  20. Effects of Er:YAG laser irradiation on human cartilage

    Science.gov (United States)

    Glinkowski, Wojciech; Brzozowska, Malgorzata; Ciszek, Bogdan; Rowinski, Jan; Strek, Wieslaw

    1996-03-01

    Irradiation of the hyaline or fibrous cartilage excised from the body of a human cadaver with Er:YAG laser beam, single pulse with a dose of 1 J, produces a crater with a depth of approximately 500 micrometers and a diameter varying from 5 to 300 micrometers. Histological examination has revealed that the laser-made craters were surrounded by a thin rim (2-10 micrometer) of charred and coagulated tissue. No damage was observed in the cartilage surrounding the rim. The presence of sharp demarcation between the tissue areas ablated by laser energy and the undamaged areas argues for the potential usefulness of the Er:YAG laser in surgery of cartilages.

  1. Effect of Low-level LASER Therapy on P6 Acupoint to Control Gag Reflex in Children: A Clinical Trial

    Directory of Open Access Journals (Sweden)

    Himani Goel

    2017-10-01

    Conclusion: LLLT on PC6 point was found to be effective in lowering anxiety levels as observed by faces modified anxiety rating scale. Further, it was authenticated as the pulse rates were significantly reduced and oxygen saturation levels were significantly increased. Also, gag reflex was significantly controlled when LASER stimulation was done at PC6.

  2. Evaluation of muscle regeneration in aged animals after treatment with low-level laser therapy Avaliação da regeneração muscular em animais idosos após tratamento com laser de baixa intensidade

    Directory of Open Access Journals (Sweden)

    Adriana Pertille

    2012-12-01

    Full Text Available BACKGROUND: The aging process and its associated morphophysiological changes trigger a reduction in the regenerative ability of the satellite cells, a reduction of vascular tissue and an increase in the production of fibroblasts, developing a cellular environment unfavorable for muscle regeneration. OBJECTIVE: The aim of this study was to evaluate the effect of low-level laser therapy on the muscle regeneration of old experimental rat models after contusion. METHOD: A total of 25 old rats,18 months old, were divided into three groups: control group (CT without treatment; injury group (IN with muscle contusion and without treatment and laser group (LA with contusion and low-level laser therapy, 830 nm, 30 mW e 4 J/cm². The no invasive contusion was induced in the Tibialis Anterior muscle and the samples were collected after 7 and 21 treatment sessions. The muscle was evaluated by Light Microscopy and Immunoblotting. RESULTS: After 21 days of treatment there was a significant reduction in the areas of inflammation/regeneration of the LA 21 group compared to IN 21 group. The cross-sectional area of the fibers in regeneration was not statistically different between the groups. Molecular analysis showed that the content of MyoD was statistically reduced in the IN 21 group compared to the CT group. The Myogenin content was increased in the IN 21 group compared to the CT group. Ultimately, the content of TGF-β1 on the IN 21 group was higher when compared to the CT group. CONCLUSION: Considering the parameters used, the laser therapy demonstrated to be effective for muscle regeneration in old rats, however only through its anti-inflammatory effect.CONTEXTUALIZAÇÃO: O processo de envelhecimento e suas consequentes alterações morfofisiológicas desencadeiam redução da habilidade regenerativa das células satélites, redução da vascularização tecidual e aumento da produção de fibroblastos, desenvolvendo-se um ambiente celular desfavor

  3. Thermal Changes of Maize Seed by Laser Irradiation

    Science.gov (United States)

    Hernandez-Aguilar, C.; Dominguez-Pacheco, A.; Cruz-Orea, A.

    2015-09-01

    In this research, the thermal evolution in maize seeds ( Zea mays L.) was studied when low-intensity laser irradiation was applied during 60 s. The seeds were irradiated in three different conditions: suspended in air, placed on an aluminum surface, and finally placed on a cardboard; the evolution of the seed temperature was measured by an infrared camera. Photoacoustic spectroscopy and the Rosencwaig and Gersho model were used to determine the optical absorption coefficient (β ) of the seeds. The results indicate that using 650 nm laser light and 27.4 mW, it is possible to produce temperature changes (up to 9.06°C after 1 min) on the seeds. Comparing the mean temperature of the seeds, during and after the incidence of light from a laser, it was found that there were statistically significant differences (P≤ 0.05) from time t1 to time t_{16} (t1 to t_{16}) and t3 to t_{16}, for the laser turned on and off, respectively. The seed condition that had the highest temperature variation, relative to the initial temperature (during the irradiation laser exposure), involved the seeds suspended in air. With regard to the stage of decay of the temperature, it was found that the seed condition that decays more slowly was the seed placed on the cardboard. It was also found that black-dyed maize seeds are optically opaque in the 300 nm to 700 nm range Also, the thermal diffusion length is smaller than the optical penetration length. In the present investigation, it was shown that there is a thermal component associated with the mechanisms of laser biostimulation, which is also a function of the container materials of the seed. In this way, the effects of laser treatment on maize seeds involve at least a temperature effect. It is important to know the temperature changes in the seeds that have been irradiated with a laser beam since they could have substantial practical and theoretical importance.

  4. Diffuse scattering from laser-irradiated plane targets

    International Nuclear Information System (INIS)

    Kessel, C.G.M. van; Olsen, J.N.; Sachsenmaier, P.; Sigel, R.; Eidmann, K.; Godwin, R.P.

    1976-11-01

    Optical calorimetry of the laser radiation scattered from plane targets irradiated by 0.3 Joule/30 ps Nd-laser pulses with intensities up to 10 16 W cm -2 has been performed with an emphasis on diffuse scattering. Diffuse scattering outside the solid angle of the focusing lens is found to be a major reflection loss from the target. A fraction of 0.3 to 0.5 of the incident pulse energy was absorbed in the target with only a very weak dependence on pulse energy and target material. (orig.) [de

  5. LPI studies with grazing incidence irradiation at the Nike laser

    Science.gov (United States)

    Weaver, J.; Kehne, D.; Schmitt, A.; Obenschain, S.; Serlin, V.; Oh, J.; Lehmberg, R.; Seely, J.

    2013-10-01

    Studies of laser plasma instabilities (LPI) at the Nike laser facility at NRL have previously concentrated on planar targets irradiated with their surface normal aligned to the central axis of the laser. Shots with planar targets rotated up 60° to the laser have shown changes in thresholds for the two-plasmon decay instability and stimulated Raman scattering near the quarter critical region. In the case of rotated low-Z targets, spectra were observed to shift to lower wavelength and were substantially stronger in the visible and ultraviolet spectral ranges. The low-Z target data show growth at an incident intensity slightly below (~30%) the threshold values observed at normal incidence. A rapid rise in signal level over the same laser intensities was also observed in the hard x-ray data which serve as an overall indicator of LPI activity. Shots with rotated planar high-Z targets showed that the visible and ultraviolet emissions dropped significantly when compared to low-Z targets in the same geometry. This presentation will include results from upcoming experiments to determine the LPI signal for low-Z, high-Z, and high-Z coated targets at lower laser intensities for several angles of target rotation. Shots with widely separated laser beams are also planned to explore cross beam energy transport at Nike. Work supported by DoE/NNSA.

  6. Greater-than-Class C low-level waste characterization. Appendix G: Evaluation of potential for greater-than-Class C classification of irradiated hardware generated by utility-operated reactors

    International Nuclear Information System (INIS)

    Cline, J.E.

    1991-08-01

    This study compiles and evaluates data from many sources to expand a base of data from which to estimate the activity concentrations and volumes of greater-than-Class C low-level waste that the Department of Energy will receive from the commercial power industry. Sources of these data include measurements of irradiated hardware made by or for the utilities that was classified for disposal in commercial burial sites, measurements of neutron flux in the appropriate regions of the reactor pressure vessel, analyses of elemental constituents of the particular structural material used for the components, and the activation analysis calculations done for hardware. Evaluations include results and assumptions in the activation analyses. Sections of this report and the appendices present interpretation of data and the classification definitions and requirements

  7. Effect of low-level laser therapy in the treatment of cochlear tinnitus: a double-blind, placebo-controlled study.

    Science.gov (United States)

    Dehkordi, Mahboobeh Adami; Einolghozati, Sasan; Ghasemi, Seyyed Mohsen; Abolbashari, Samaneh; Meshkat, Mojtaba; Behzad, Hadi

    2015-01-01

    Many treatments for chronic tinnitus have been attempted, but the condition remains difficult to cure, especially in the case of cochlear tinnitus. We conducted a prospective, double-blind, placebo-controlled study to assess the effect of low-dose laser therapy on chronic cochlear tinnitus. Our study population was made up of 66 patients-33 who received active laser treatment (case group) and 33 who received inactive dummy treatment (control group). Patients in the laser group received 5 mV with a wavelength of 650 nm for 20 minutes a day, 5 days a week, for 4 weeks. The controls followed the same schedule, but they were "treated" with an inactive device. The degree of tinnitus was evaluated before and after treatment in each group in three ways: (1) the Tinnitus Severity Index (TSI), (2) a subjective 10-point self-assessment scale for tinnitus loudness, and (3) the Tinnitus Evaluation Test (TET). At study's end, we found no statistically significant differences between the case and control groups in the number of patients who experienced a reduction in TSI values (p = 0.589) or a reduction in subjective self-assessment scores (p = 0.475). Nor did we find any significant reductions in the loudness (p = 0.665) and frequency (p = 0.396) of tinnitus as determined by the TET. We conclude that 5-mV laser therapy with a wavelength of 650 nm is no better than placebo for improving hearing thresholds overall or for treating tinnitus with regard to age, sex, environmental noise level, and the duration of tinnitus.

  8. Effect Of Laser Irradiation On Biosynthesis Of Antibiotics

    International Nuclear Information System (INIS)

    SALAMA, S.M.; MAHMOUD, S.M.; EL-KABBANY, H.M.

    2010-01-01

    An investigation concerning the effect of He:Ne laser irradiation on some isolated actinomycetes was carried out. Seven isolated actinomycetes were considered as most potent producing broad spectrum antibiotics. The strains have been identified on the basis of taxonomic studies as Streptomyces nogalator (H12), Streptomyces griseoluteus (YM23), Amycolatopsis mediterranei (B40), Glycomyces harbinensis (KA16), Streptosporangium corrugatum (B67), Streptoalloteichus hindustamus (B74) and Streptomyces aurantiogriseus (S15). Seven genotypes were chosen after He:Ne laser irradiation as representative for each isolated strain. The active metabolite from most potent genotype of Streptomyces nogalator (H12) was extracted by ethyl acetate then concentrated under vacuo and the crude fraction was purified using thin layer and column chromatography. Ultra violet maximum absorption peak was recorded at 231.5 and 206 nm. The IR and NMR were consulted to confirm the chemical characteristics of the antibiotic. The biological activity and toxicity were also investigated.

  9. 弱激光疗法在创面愈合中的作用研究进展%Advancement in the research of effect of low level laser therapy on wound healing

    Institute of Scientific and Technical Information of China (English)

    毛和水; 姚敏; 方勇

    2012-01-01

    Low level laser therapy (LLLT) is a therapeutic method which regulates the biological behavior of cells with light.The effects of LLLT consist of promotion of tissue repair,inhibition of inflammation,and relief of pain by promoting or inhibiting the cell proliferation,increasing or decreasing the release of some bioactive substances.Therefore,LLLT is also known as photomodulation.At present,there are many relevant experimental studies of LLLT abroad,and they are also used clinically.This article reviews the effect of LLLT on wound healing.

  10. A laserterapia de baixa potência melhora o desempenho muscular mensurado por dinamometria isocinética em humanos Low-level laser therapy enhances muscular performance as measured by isokinetic dynamometry in humans

    Directory of Open Access Journals (Sweden)

    Ernesto Cesar Pinto Leal Junior

    2010-12-01

    Full Text Available A fadiga muscular é uma nova área de pesquisa em laserterapia, com poucos estudos conduzidos. Embora a laserterapia de baixa potência (LBP previamente ao exercício tenha apresentado resultados positivos no retardo da fadiga musculoesquelética, ainda não foi estudada utilizando-se a dinamometria isocinética para mensurar desempenho e fadiga muscular. Este estudo tem o objetivo de avaliar os efeitos da LBP (655 nm, 50 mW, 2,4 J por ponto e 12 J de energia total sobre o desempenho e fadiga muscular do músculo tibial anterior, utilizando dinamometria isocinética (30 repetições de contração concêntrica em 14 indivíduos saudáveis sedentários do sexo masculino. Os voluntários foram avaliados ao efetuar 30 repetições isocinéticas de dorsiflexão de tornozelo à velocidade angular de 240°.seg-1. Os resultados mostram que, quando os voluntários foram tratados com LBP antes do exercício, os valores do pico de torque (30,91±5,86 N.m foram significativamente superiores, comparados a três medições anteriores sem a aplicação de LBP (24,92±7,45 N.m, pSkeletal muscle fatigue is a novel research area in laser therapy, there being few studies carried out. Though low-level laser therapy (LLLT applied prior to exercise has showed positive results in delaying skeletal muscle fatigue, no studies could be found that measured muscle performance and fatigue by means of isokinetic dynamometry. This clinical trial aims at assessing the effects of LLLT (655 nm, 50 mW and 12 J total energy delivered on anterior tibialis muscle performance and fatigue by means of isokinetic dynamometry (30 concentric-mode repetitions at 240º.sec-1 angular speed in 14 healthy male subjects. Results show that, when volunteers had been treated with LLLT prior to exercise, torque peak values (30.91±5.86 N.m were significantly higher than those of three previous measurements with no LLLT (24.92±7.45 N.m, p<0.001; 26.83±7.74 N.m, p<0.01; and 26.00±7.88 N.m, p<0

  11. Research on interaction of laser light and non-metals. Evaluation of laser irradiation behavior to concrete

    International Nuclear Information System (INIS)

    Yamada, Tomonori; Muramatsu, Toshiharu

    2015-02-01

    In this study the response of hardened cement pastes, which are a major component of concrete, to laser irradiation was investigated under various experimental conditions aiming at the future application to “laser-processing” of concrete. (1) 75 tests were performed with combinations of following experimental conditions: (a) a water/cement ratio of the hardened cement pastes was either of 0.25, 0.30, or 0.35; (b) a laser power density was either of 100, 200, 300, 400, or 500 W/cm 2 ; and (c) laser irradiation duration was ranging from 1 to 40 seconds. It was found that hardened cement paste subjected to laser irradiation explodes very easily to be hollowed in all the experimental conditions; this response is applicable to “laser-drilling” of a hardened cement paste. The “laser-drilling” speeds up following to laser power increment or to irradiation time extension. It was also found that samples tend to melt rather than explode under the irradiation with a smaller laser power density (100 W/cm 2 ) at a high water/cement ratio (0.35). (2) Totally 75 laser irradiation tests for fixed mortar blocks were performed with combinations of following experimental conditions: (a) fine aggregate in the mortar blocks was either of quartz, limestone, or Nachiguro-ishi; (b) a laser power density was either of 100, 200, 300, 400, or 500 W/cm 2 ; and (c) laser irradiation duration was ranging from 0.2 to 40 seconds. Although it was found that all kinds of the mortar fuse under laser irradiation after all, difference in the response to laser irradiation among the mortars was also found; energy density required to fuse the mortar including limestone was larger than that required to fuse the mortar including quartz or Nachiguro-ishi. (author)

  12. Toxicity of laser irradiated photoactive fluoride PrF3 nanoparticles toward bacteria

    International Nuclear Information System (INIS)

    Pudovkin, M S; Korableva, S L; Krasheninnicova, A O; Nizamutdinov, A S; Semashko, V V; Zelenihin, P V; Alakshin, E M; Nevzorova, T A

    2014-01-01

    The article is devoted to exploration of biological effects of crystalline PrF 3 nanoparticles toward Salmonella typhimurium TA 98 bacteria under the laser irradiation. Obtained results show bactericidal activity of PrF 3 nanoparticles and optimal parameters of laser irradiation (power of laser irradiation, wavelength, diameter of the laser spoil, and exposure time) have been found under which the effects of bactericidal activity become the most significant. Survival of bacterial cells under laser irradiation with wavelength 532 nm in colloidal solution of PrF 3 nanoparticles was 39%, 34%, 20% for exposure times 5 minutes, 15 minutes and 30 minutes, correspondingly

  13. Chalcogen doping of silicon via intense femtosecond-laser irradiation

    International Nuclear Information System (INIS)

    Sheehy, Michael A.; Tull, Brian R.; Friend, Cynthia M.; Mazur, Eric

    2007-01-01

    We have previously shown that doping silicon with sulfur via femtosecond-laser irradiation leads to near-unity absorption of radiation from ultraviolet wavelengths to below band gap short-wave infrared wavelengths. Here, we demonstrate that doping silicon with two other group VI elements (chalcogens), selenium and tellurium, also leads to near-unity broadband absorption. A powder of the chalcogen dopant is spread on the silicon substrate and irradiated with femtosecond-laser pulses. We examine and compare the resulting morphology, optical properties, and chemical composition for each chalcogen-doped substrate before and after thermal annealing. Thermal annealing reduces the absorption of below band gap radiation by an amount that correlates with the diffusivity of the chalcogen dopant used to make the sample. We propose a mechanism for the absorption of below band gap radiation based on defects in the lattice brought about by the femtosecond-laser irradiation and the presence of a supersaturated concentration of chalcogen dopant atoms. The selenium and tellurium doped samples show particular promise for use in infrared photodetectors as they retain most of their infrared absorptance even after thermal annealing-a necessary step in many semiconductor device manufacturing processes

  14. Thermal shock testing of ceramics with pulsed laser irradiation

    International Nuclear Information System (INIS)

    Benz, R.; Naoumidis, A.; Nickel, H.

    1986-04-01

    Arguments are presented showing that the resistance to thermal stressing (''thermal shock'') under pulsed thermal energy deposition by various kinds of beam irradiations is approximately proportional to Φ a √tp, where Φ a is the absorbed power density and tp is the pulse length, under conditions of diffusivity controlled spreading of heat. In practical beam irradiation testing, incident power density, Φ, is reported. To evaluate the usefulness of Φ√tp as an approximation to Φ a √tp, damage threshold values are reviewed for different kinds of beams (electron, proton, and laser) for a range of tp values 5x10 -6 to 2 s. Ruby laser beam irradiation tests were made on the following ceramics: AlN, BN, graphite, αSiC, β-SiC coated graphites, (α+β)Si 3 N 4 , CVD (chemical vapor deposition) TiC coated graphite, CVD TiC coated Mo, and CVD TiN coated IN 625. The identified failure mechanisms are: 1. plastic flow followed by tensile and bend fracturing, 2. chemical decomposition, 3. melting, and 4. loss by thermal spallation. In view of the theoretical approximations and the neglect of reflection losses there is reasonable accord between the damage threshold Φ√tp values from the laser, electron, and proton beam tests. (orig./IHOE)

  15. Eficácia a curto prazo do laser de baixa intensidade em pacientes com osteoartrite do joelho: ensaio clínico aleatório, placebo-controlado e duplo-cego Short-term efficacy of low-level laser therapy in patients with knee osteoarthritis: a randomized placebo-controlled, double-blind clinical trial

    Directory of Open Access Journals (Sweden)

    Vanessa Ovanessian Fukuda

    2011-10-01

    Full Text Available OBJETIVO: Este estudo foi designado para avaliar a eficácia a curto prazo da laserterapia de baixa intensidade (LBI na melhora da dor e função em pacientes portadores de osteoartrite (OA do joelho. MÉTODOS: Participaram deste ensaio clínico aleatório, duplo-cego e controlado 47 pacientes (79 joelhos de ambos os sexos portadores de OA do joelho, que foram distribuídos aleatoriamente em dois grupos; grupo laser com 25 pacientes (41 joelhos e grupo placebo com 22 pacientes (38 joelhos. A LBI foi realizada três vezes por semana totalizando nove sessões, com uso do laser AsGa de 904nm, 60mW de potência média e 0,5cm² de área do feixe, sendo irradiados nove pontos no joelho com energia de 3,0J por ponto. O grupo placebo foi tratado com o mesmo aparelho de laser, porém com uma caneta selada. As avaliações Lequesne, escala visual numérica (EVN, Timed Up and Go (TUG, goniometria e dinamometria foram realizadas antes do início do tratamento e após as nove sessões da LBI. RESULTADOS: Foi encontrada melhora significante da dor e função para todas as avaliações aplicadas no grupo laser. Quando comparado o grupo laser ao grupo placebo encontrou-se diferença significante para as avaliações EVN-Repouso e Lequesne. CONCLUSÃO: O tratamento com a LBI melhora a dor e função a curto prazo de pacientes portadores de OA do joelho.OBJECTIVE: This study was designed to evaluate the short-term efficacy of low-level laser therapy (LLLT for improving pain and function in patients with knee osteoarthritis. METHODS: Forty-seven patients with knee osteoarthritis (79 knees, of both genders, participated in this randomized controlled double-blind clinical trial. They were randomly allocated to two groups: laser group with 25 patients (41 knees and placebo group with 22 patients (38 knees. LLLT was performed three times a week, totaling nine sessions, using a AsGa 904 nm laser with mean power of 60 mW and beam area of 0.5 cm². Nine points were

  16. Uso combinado da laserterapia de baixa potência e da inibição da ciclooxigenase-2 na reepitelização de ferida incisional em pele de camundongos: um estudo pré-clínico Combined use of low level laser therapy and cyclooxygenase-2 selective inhibition on skin incisional wound reepithelialization in mice: a preclinical study

    Directory of Open Access Journals (Sweden)

    Cíntia Helena Santuzzi

    2011-04-01

    to modulate inflammatory response; however, their effect on wound reepithelialization are not well understood. OBJECTIVE: To evaluate the isolated and combined effects of low level laser therapy and ICOX2 in the reepithelization of skin incisional wounds in mice. METHODS: We induced a 1-cm wound on the back of each mouse, which were divided into four groups (N = 20: control, laser therapy, treated with celecoxib and combined therapy. The animals in the celecoxib and combined therapy groups were treated with celecoxib for 10 days before skin incision. The experimental wounds were irradiated with He-Ne low power laser (632nm, dose: 4J/cm2 in scanning for 12 seconds during three consecutive days in the laser therapy and combined therapy groups. The animals were sacrificed 3 days after surgery. Samples of the wounds were collected and stained (Masson's Trichrome for histomorphometric analysis. RESULTS: Both the laser therapy group and the celecoxib group showed an increase in skin reepithelialization compared to the control group; however, the combined therapy group showed no differences. As for keratinization, the laser therapy and combined therapy groups showed a reduction in keratinocytes compared with the control group. CONCLUSION: The results show that the use of low level laser therapy and ICOX2 in isolation increases epithelial cells, but only low level laser therapy reduced skin keratinocytes. The combined treatment restores innate epithelialization and decreases keratinization in spite of accelerating wound contraction with improvement in the organization of the wound in the skin of mice.

  17. Low-power laser irradiation improves histomorphometrical parameters and bone matrix organization during tibia wound healing in rats.

    Science.gov (United States)

    Garavello-Freitas, I; Baranauskas, V; Joazeiro, P P; Padovani, C R; Dal Pai-Silva, M; da Cruz-Höfling, Maria Alice

    2003-01-01

    The influence of daily energy doses of 0.03, 0.3 and 0.9 J of He-Ne laser irradiation on the repair of surgically produced tibia damage was investigated in Wistar rats. Laser treatment was initiated 24 h after the trauma and continued daily for 7 or 14 days in two groups of nine rats (n=3 per laser dose and period). Two control groups (n=9 each) with injured tibiae were used. The course of healing was monitored using morphometrical analysis of the trabecular area. The organization of collagen fibers in the bone matrix and the histology of the tissue were evaluated using Picrosirius-polarization method and Masson's trichrome. After 7 days, there was a significant increase in the area of neoformed trabeculae in tibiae irradiated with 0.3 and 0.9 J compared to the controls. At a daily dose of 0.9 J (15 min of irradiation per day) the 7-day group showed a significant increase in trabecular bone growth compared to the 14-day group. However, the laser irradiation at the daily dose of 0.3 J produced no significant decrease in the trabecular area of the 14-day group compared to the 7-day group, but there was significant increase in the trabecular area of the 15-day controls compared to the 8-day controls. Irradiation increased the number of hypertrophic osteoclasts compared to non-irradiated injured tibiae (controls) on days 8 and 15. The Picrosirius-polarization method revealed bands of parallel collagen fibers (parallel-fibered bone) at the repair site of 14-day-irradiated tibiae, regardless of the dose. This organization improved when compared to 7-day-irradiated tibiae and control tibiae. These results show that low-level laser therapy stimulated the growth of the trabecular area and the concomitant invasion of osteoclasts during the first week, and hastened the organization of matrix collagen (parallel alignment of the fibers) in a second phase not seen in control, non-irradiated tibiae at the same period. The active osteoclasts that invaded the regenerating site were

  18. Physiological characteristics of cucumber seed production plants by presowing laser and gamma irradiation

    International Nuclear Information System (INIS)

    Cholakov, D.; Petkova, V.

    1994-01-01

    Seeds from G-3 maternal line of hybrid cucumber cultivar Pobeda F 1 were treated with helium-neon 632.8 nm laser-exit power 20 mW and gamma-rays ( 60 Co) in a field experiment under conditions suitable for hybrid seed production. The irradiation was carried out a week before sowing and the following variants were investigated: 1. sevenfold laser irradiation; 2. 10 Gy gamma irradiation; 3. combined laser + gamma rays irradiation. Seeds from the parent line were not irradiated. A positive effect of irradiation on the photosynthetic intensity, content of plastid pigments in leaves and activity of catalase and peroxidase has been observed. (author)

  19. High resolution laser beam induced current images under trichromatic laser radiation: approximation to the solar irradiation.

    Science.gov (United States)

    Navas, F J; Alcántara, R; Fernández-Lorenzo, C; Martín-Calleja, J

    2010-03-01

    A laser beam induced current (LBIC) map of a photoactive surface is a very useful tool when it is necessary to study the spatial variability of properties such as photoconverter efficiency or factors connected with the recombination of carriers. Obtaining high spatial resolution LBIC maps involves irradiating the photoactive surface with a photonic beam with Gaussian power distribution and with a low dispersion coefficient. Laser emission fulfils these characteristics, but against it is the fact that it is highly monochromatic and therefore has a spectral distribution different to solar emissions. This work presents an instrumental system and procedure to obtain high spatial resolution LBIC maps in conditions approximating solar irradiation. The methodology developed consists of a trichromatic irradiation system based on three sources of laser excitation with emission in the red, green, and blue zones of the electromagnetic spectrum. The relative irradiation powers are determined by either solar spectrum distribution or Planck's emission formula which provides information approximate to the behavior of the system if it were under solar irradiation. In turn, an algorithm and a procedure have been developed to be able to form images based on the scans performed by the three lasers, providing information about the photoconverter efficiency of photovoltaic devices under the irradiation conditions used. This system has been checked with three photosensitive devices based on three different technologies: a commercial silicon photodiode, a commercial photoresistor, and a dye-sensitized solar cell. These devices make it possible to check how the superficial quantum efficiency has areas dependent upon the excitation wavelength while it has been possible to measure global incident photon-to-current efficiency values approximating those that would be obtained under irradiation conditions with sunlight.

  20. The oral cavity as a guide for the application of low level laser energy and its direct effect on the autonomic nervous system providing true energy healing for all health practitioners

    Science.gov (United States)

    Yolin, Herbert S.

    2008-03-01

    This manuscript is intended to demonstrate the important role that dentistry plays in regulating the balance of the Autonomic Nervous System (ANS) through the proprioceptive feedback of the posterior teeth to the brain. An old paradigm called Dental Distress Syndrome, relatively unknown in dentistry today, has at its core, the importance of the height of the posterior (back) teeth and its impact on total body health which is greatly aided by low level laser energy. The rationale behind the belief that the alteration of the posterior teeth affects the ANS begins with basic concepts in embryology. The functioning of the ANS will support the fact of Dental Distress Syndrome. Health practitioners of all disciplines can learn to recognize Dental Distress Syndrome and initiate non-invasive treatment and team with a trained dentist to enhance the wellness and health of the patient if they so desire. A synopsis of my oral paper presented to the Academy of Laser Dentistry demonstrating temporary balancing of the Autonomic Nervous System with three minutes of cold laser energy, as well as my rationale as to why results vary with different cold lasers will be discussed. Clinical case studies will be presented.

  1. Soft-tissue injuries from sports activities and traffic accidents--treatment with low-level laser therapy: a multicenter double-blind placebo-controlled clinical study on 132 patients

    Science.gov (United States)

    Simunovic, Zlatko; Trobonjaca, Tatjana

    2000-06-01

    The aim of current multicenter clinical study was to assess the efficacy of low energy-level laser therapy (LLLT) in the treatment of soft tissue injuries compared to the placebo and classical phyiotherapeutic procedures. This clinical study was conducted in two centers located in Locarno, Switzerland and Opatija, Croatia. Two types of irradiation techniques were used: (1) direct, skin contact technique for treatment of trigger points where IR diode laser 830 nm continuous wave was applied; and (2) scanning technique for irradiation of larger surface area with use of Helium Neon laser 632.8 nm combined with IR diode laser 904 nm pulsed wave. Results were evaluated according to clinical parameters like: hematoma, swelling, heat, pan and loss of function. The findings were statistically analyzed via chi- square test. Results have demonstrated that the recovery process was accelerated in 85 percent of patients treated with LLLT compared to the control group of patients. The results and advantages obtained proved once again the efficacy of LLLT as a new and successful way to treat soft tissue injuries.

  2. Realization of double-pulse laser irradiating scheme for laser ion sources

    International Nuclear Information System (INIS)

    Li Zhangmin; Jin Qianyu; Liu Wei; Zhang Junjie; Sha Shan; Zhao Huanyu; Sun Liangting; Zhang Xuezhen; Zhao Hongwei

    2015-01-01

    A double-pulse laser irradiating scheme has been designed and established for the production of highly charged ion beams at Institute of Modern Physics (IMP), Chinese Academy of Sciences. The laser beam output by a Nd : YAG laser is split and combined by a double of beam splitters, between which the split laser beams are transmitted along different optical paths to get certain time delay between each other. With the help of a quarter-wave plate before the first splitter, the energy ratio between the two laser pulses can be adjusted between 3 : 8 to 8 : 3. To testify its feasibility, a preliminary experiment was carried out with the new-developed double-pulse irradiating scheme to produce highly charged carbon ions. Comparing the results with those got from the previous single-pulse irradiating scheme, the differences in the time structure and Charge State Distribution (CSD) of the ion pulse were observed, but its mechanisms and optimization require further studies. (authors)

  3. Laser ablation of liquid surface in air induced by laser irradiation through liquid medium

    Science.gov (United States)

    Utsunomiya, Yuji; Kajiwara, Takashi; Nishiyama, Takashi; Nagayama, Kunihito; Kubota, Shiro; Nakahara, Motonao

    2010-10-01

    The pulse laser ablation of a liquid surface in air when induced by laser irradiation through a liquid medium has been experimentally investigated. A supersonic liquid jet is observed at the liquid-air interface. The liquid surface layer is driven by a plasma plume that is produced by laser ablation at the layer, resulting in a liquid jet. This phenomenon occurs only when an Nd:YAG laser pulse (wavelength: 1064 nm) is focused from the liquid onto air at a low fluence of 20 J/cm2. In this case, as Fresnel’s law shows, the incident and reflected electric fields near the liquid surface layer are superposed constructively. In contrast, when the incident laser is focused from air onto the liquid, a liquid jet is produced only at an extremely high fluence, several times larger than that in the former case. The similarities and differences in the liquid jets and atomization processes are studied for several liquid samples, including water, ethanol, and vacuum oil. The laser ablation of the liquid surface is found to depend on the incident laser energy and laser fluence. A pulse laser light source and high-resolution film are required to observe the detailed structure of a liquid jet.

  4. Avaliação imediata da dor e edema em lesão muscular induzida por formalina e tratada com laser 808 nm Immediate pain and edema assessment in muscular injury induced by formalin and treated with low-level laser (808nm

    Directory of Open Access Journals (Sweden)

    Emerson Borato

    2008-10-01

    Full Text Available O laser de baixa potência induz a bioestimulação celular, podendo acelerar a cicatrização de feridas, promover a regeneração do músculo esquelético, diminuir a resposta inflamatória, estimular a neoformação de vasos sanguíneos e diminuir a dor. O objetivo deste estudo foi analisar os efeitos de três doses de laser de baixa intensidade (808nm, na dor e edema imediatos, em ratos submetidos a lesão experimental do músculo gastrocnêmio lateral. Foram utilizados 24 ratos Wistar, distribuídos aleatoriamente em quatro grupos, sendo: GC - animais lesionados e tratados com aparelho desligado (simulacro; G20 - animais lesionados e irradiados com dose de 20J/cm²; G50 - animais lesionados e irradiados com 50J/cm; e G100 - animais lesionados e irradiados com 100J/cm². Para a produção da lesão experimental, introduziu-se 0,1mL de formalina a 5% no ventre do músculo gastrocnêmio lateral direito. A avaliação da dor ocorreu através do tempo de elevação da pata (TEP e o edema foi avaliado com auxílio de paquímetro metálico; ambas as avaliações ocorreram pré-lesão, pós-lesão, pós-tratamento, duas, oito e 24 horas pós-lesão. Os resultados mostraram aumento significativo do TEP e da avaliação com paquímetro, após a indução da lesão. Conclui-se que laser nos parâmetros utilizados não produziu diminuição na dor e edema, em animais submetidos a lesão muscular com injeção de formalina a 5%.Low-level laser therapy induces to cellular bioestimulation and can accelerate wound healing, promote skeletal muscle regeneration, decrease inflammatory response, stimulate neovascularization and decrease pain. The aim of this study was to analyze the effects of three doses of low-level laser therapy (808 nm, in the immediate pain and edema, in rats submitted to experimental injury of the lateral gastrocnemius muscle. Twenty four Wistar rats, randomly distributed in the following four groups were used: CG - injured and treated

  5. Laser-induced breakdown spectroscopy with laser irradiation resonant with vibrational transitions

    International Nuclear Information System (INIS)

    Khachatrian, Ani; Dagdigian, Paul J.

    2010-01-01

    An investigation of laser-induced breakdown spectroscopy (LIBS) of polymers, both in bulk form and spin coated on Si wafers, with laser irradiation in the mid-infrared spectral region is presented. Of particular interest is whether the LIBS signals are enhanced when the laser wavelength is resonant with a fundamental vibrational transition of the polymer. Significant increases in the LIBS signals were observed for irradiation on hydride stretch fundamental transitions, and the magnitude of the enhancement showed a strong dependence on the mode excited. The role of the substrate was investigated by comparison of results for bulk and spin-coated samples. The polymers investigated were Nylon 12 and poly(vinyl alcohol-co-ethylene).

  6. Low-level waste management

    International Nuclear Information System (INIS)

    Levin, G.B.

    1980-01-01

    An overview of the current situation in the United States and a look to the future of low-level waste management are presented. Current problems and challenges are discussed, such as: the need of additional disposal sites in the future; risks and costs involved in transport of low-level wastes; reduction of low-level waste volume through smelting, incineration, and storage for wastes containing nuclides with short half lives; development of a national policy for the management of low-level waste, and its implementation through a sensible system of regulations. Establishing a success with low-level waste management should provide the momentum and public confidence needed to continue on and to resolve the technical and politically more difficult low-level waste problems

  7. The osmotic fragility of human erythrocytes is inhibited by laser irradiation

    International Nuclear Information System (INIS)

    Habodaszova, D.; Sikurova, L.; Waczulikova, I.

    2004-01-01

    In this study we investigated the influence of green laser irradiation (532 nm, 30 mW, 31,7 J/cm 2 ) on the membrane integrity of human erythrocytes and compared the results with the effect of infrared laser irradiation (810 nm, 50 mW, 31,3 J/cm 2 ). To evaluate the membrane integrity of erythrocytes, one clinical parameter, the osmotic fragility, was investigated. We observed a decrease in osmotic fragility of the erythrocytes after irradiation by the green laser light as well as by the infrared laser compared to non-irradiated controls (Authors)

  8. Research on temperature characteristics of laser energy meter absorber irradiated by ms magnitude long pulse laser

    Science.gov (United States)

    Li, Nan; Qiao, Chunhong; Fan, Chengyu; Zhang, Jinghui; Yang, Gaochao

    2017-10-01

    The research on temperature characteristics for large-energy laser energy meter absorber is about continuous wave (CW) laser before. For the measuring requirements of millisecond magnitude long pulse laser energy, the temperature characteristics for absorber are numerically calculated and analyzed. In calculation, the temperature field distributions are described by heat conduction equations, and the metal cylinder cavity is used for absorber model. The results show that, the temperature of absorber inwall appears periodic oscillation with pulse structure, the oscillation period and amplitude respectively relate to the pulse repetition frequency and single pulse energy. With the wall deep increasing, the oscillation amplitude decreases rapidly. The temperature of absorber outerwall is without periodism, and rises gradually with time. The factors to affect the temperature rise of absorber are single pulse energy, pulse width and repetition frequency. When the laser irradiation stops, the temperature between absorber inwall and outerwall will reach agreement rapidly. After special technology processing to enhance the capacity of resisting laser damage for absorber inwall, the ms magnitude long pulse laser energy can be obtained with the method of measuring the temperature of absorber outerwall. Meanwhile, by optimization design of absorber structure, when the repetition frequency of ms magnitude pulse laser is less than 10Hz, the energy of every pulse for low repetition frequency pulse sequence can be measured. The work offers valuable references for the design of ms magnitude large-energy pulse laser energy meter.

  9. Can low-level laser therapy (LLLT) associated with an aerobic plus resistance training change the cardiometabolic risk in obese women? A placebo-controlled clinical trial.

    Science.gov (United States)

    Duarte, Fernanda Oliveira; Sene-Fiorese, Marcela; de Aquino Junior, Antonio Eduardo; da Silveira Campos, Raquel Munhoz; Masquio, Deborah Cristina Landi; Tock, Lian; Garcia de Oliveira Duarte, Ana Claudia; Dâmaso, Ana Raimunda; Bagnato, Vanderlei Salvador; Parizotto, Nivaldo Antonio

    2015-12-01

    Obesity is one of the most important link factors to coronary artery disease development mainly due to the pro-inflammatory and pro-thrombotic states favoring atherosclerosis progression. The LLLT acts in the cellular metabolism and it is highly effective to improve inflammation. The same occur in response to different kinds of exercise. However, we have not known the associate effects using LLLT therapies with aerobic plus resistance training as strategy specifically with target at human obesity control and its comorbidities. Investigate the effects of the LLLT associated with aerobic plus resistance training on cardiometabolic risk factors in obese women. Women aged 20-40 years (BMI ≥ 30 kg/m(2)), were divided into 2 groups: Phototherapy (PHOTO) and Placebo. They were trained aerobic plus resistance exercises (in a concurrent mode), 1h, 3 times/week during 16 weeks. Phototherapy was applied after each exercise session for 16 min, with infrared laser, wavelength 808 nm, continuous output, power 100 mW, and energy delivery 50 J. The body composition was measured with bioimpedance. Inflammatory mark concentrations were measured using a commercially available multiplex. LLLT associated with aerobic plus resistance training was effective in decrease neck (P=0.0003) and waist circumferences (P=0.02); percentual of fat (P=0.04); visceral fat area (P=0.02); HOMA-IR (P=0.0009); Leptin (P=0.03) and ICAM (P=0.03). Also, the reduction in leptin (P=0.008) and ICAM-1 (0, 05) was much more expressive in the phototherapy group in comparison to placebo group when analyzed by delta values. LLLT associated with concurrent exercise (aerobic plus resistance training) potentiates the exercise effects of decreasing the cardiometabolic risk factors in obese woman. These results suggest the LLLT associated with exercises as a new therapeutic tool in the control of obesity and its comorbidities for obese people, targeting to optimize the strategies to control the cardiometabolic risk

  10. Efficacy and safety of a low-level laser device in the treatment of male and female pattern hair loss: a multicenter, randomized, sham device-controlled, double-blind study.

    Science.gov (United States)

    Jimenez, Joaquin J; Wikramanayake, Tongyu C; Bergfeld, Wilma; Hordinsky, Maria; Hickman, Janet G; Hamblin, Michael R; Schachner, Lawrence A

    2014-04-01

    Male and female pattern hair loss are common, chronic dermatologic disorders with limited therapeutic options. In recent years, a number of commercial devices using low-level laser therapy have been promoted, but there have been little peer-reviewed data on their efficacy. To determine whether treatment with a low-level laser device, the US FDA-cleared HairMax Lasercomb®, increases terminal hair density in both men and women with pattern hair loss. Randomized, sham device-controlled, double-blind clinical trials were conducted at multiple institutional and private practices. A total of 146 male and 188 female subjects with pattern hair loss were screened. A total of 128 male and 141 female subjects were randomized to receive either a lasercomb (one of three models) or a sham device in concealed sealed packets, and were treated on the whole scalp three times a week for 26 weeks. Terminal hair density of the target area was evaluated at baseline and at 16- and 26-week follow-ups, and analyzed to determine whether the hypothesis formulated prior to data collection, that lasercomb treatment would increase terminal hair density, was correct. The site investigators and the subjects remained blinded to the type of device they dispensed/received throughout the study. The evaluator of masked digital photographs was blinded to which trial arm the subject belonged. Seventy-eight, 63, 49, and 79 subjects were randomized in four trials of 9-beam lasercomb treatment in female subjects, 12-beam lasercomb treatment in female subjects, 7-beam lasercomb treatment in male subjects, and 9- and 12-beam lasercomb treatment in male subjects, compared with the sham device, respectively. Nineteen female and 25 male subjects were lost to follow-up. Among the remaining 122 female and 103 male subjects in the efficacy analysis, the mean terminal hair count at 26 weeks increased from baseline by 20.2, 20.6, 18.4, 20.9, and 25.7 per cm2 in 9-beam lasercomb-treated female subjects, 12-beam

  11. Thermal transport measurements of uv laser irradiated spherical targets

    International Nuclear Information System (INIS)

    Jaanimagi, P.A.; Delettrez, J.; Henke, B.L.; Richardson, M.C.

    1985-01-01

    New measurements are presented of thermal transport in spherical geometry using time-resolved x-ray spectroscopy. We determine the time dependence of the mass ablation rate m(dot) by following the progress of the ablation surface through thin layers of material embedded at various depths below the surface of the target. These measurements made with 6 and 12 uv (351 nm) beams from OMEGA are compared to previous thermal transport data and are in qualitative agreement with detailed LILAC hydrodynamic code simulations which predict a sharp decrease in m(dot) after the peak of the laser pulse. Non-uniform laser irradiation of the target results in the anomalously high values of m(dot) measured in these experiments

  12. Reducing wall plasma expansion with gold foam irradiated by laser

    International Nuclear Information System (INIS)

    Zhang, Lu; Ding, Yongkun; Jiang, Shaoen; Yang, Jiamin; Li, Hang; Kuang, Longyu; Lin, Zhiwei; Jing, Longfei; Li, Liling; Deng, Bo; Yuan, Zheng; Chen, Tao; Yuan, Guanghui; Tan, Xiulan; Li, Ping

    2015-01-01

    The experimental study on the expanding plasma movement of low-density gold foam (∼1% solid density) irradiated by a high power laser is reported in this paper. Experiments were conducted using the SG-III prototype laser. Compared to solid gold with 19.3 g/cc density, the velocities of X-ray emission fronts moving off the wall are much smaller for gold foam with 0.3 g/cc density. Theoretical analysis and MULTI 1D simulation results also show less plasma blow-off, and that the density contour movement velocities of gold foam are smaller than those of solid gold, agreeing with experimental results. These results indicate that foam walls have advantages in symmetry control and lowering plasma fill when used in ignition hohlraum

  13. Reducing wall plasma expansion with gold foam irradiated by laser

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lu; Ding, Yongkun, E-mail: ding-yk@vip.sina.com; Jiang, Shaoen, E-mail: jiangshn@vip.sina.com; Yang, Jiamin; Li, Hang; Kuang, Longyu; Lin, Zhiwei; Jing, Longfei; Li, Liling; Deng, Bo; Yuan, Zheng; Chen, Tao; Yuan, Guanghui; Tan, Xiulan; Li, Ping [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-986, Mianyang 621900 (China)

    2015-11-15

    The experimental study on the expanding plasma movement of low-density gold foam (∼1% solid density) irradiated by a high power laser is reported in this paper. Experiments were conducted using the SG-III prototype laser. Compared to solid gold with 19.3 g/cc density, the velocities of X-ray emission fronts moving off the wall are much smaller for gold foam with 0.3 g/cc density. Theoretical analysis and MULTI 1D simulation results also show less plasma blow-off, and that the density contour movement velocities of gold foam are smaller than those of solid gold, agreeing with experimental results. These results indicate that foam walls have advantages in symmetry control and lowering plasma fill when used in ignition hohlraum.

  14. Preparing, Loading and Shipping Irradiated Metals in Canisters Classified as Remote-Handled (RH) Low-Level Waste (LLW) From Oak Ridge National Laboratory (ORNL) to the Nevada Test Site (NTS)

    International Nuclear Information System (INIS)

    McClelland, B.C.; Moore, T.D.

    2006-01-01

    Irradiated metals, classified as remote-handled low-level waste generated at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, were containerised in various sized canisters for long-term storage. The legacy waste canisters were placed in below-grade wells located at the 7827 Facility until a pathway for final disposal at the Nevada Test Site (NTS) could be identified and approved. Once the pathway was approved, WESKEM, LLC was selected by Bechtel Jacobs Company, LLC to prepare, load, and ship these canisters from ORNL to the NTS. This paper details some of the technical challenges encountered during the retrieval process and solutions implemented to ensure the waste was safely and efficiently over-packed and shipped for final disposal. The technical challenges detailed in this paper include: 1) how to best perform canister/lanyard pre-lift inspections since some canisters had not been moved in ∼10 years, so deterioration was a concern; 2) replacing or removing damaged canister lanyards; 3) correcting a mis-cut waste canister lanyard resulting in a shielded overpack lid not seating properly; 4) retrieving a stuck canister; and 5) developing a path forward after an overstrained lanyard failed causing a well shield plug to fall and come in contact with a waste canister. Several of these methods can serve as positive lessons learned for other projects encountering similar situations. (authors)

  15. Thermal imaging of high power diode lasers subject to back-irradiance

    Science.gov (United States)

    Li, C.; Pipe, K. P.; Cao, C.; Thiagarajan, P.; Deri, R. J.; Leisher, P. O.

    2018-03-01

    CCD-based thermoreflectance imaging and finite element modeling are used to study the two-dimensional (2D) temperature profile of a junction-down broad-area diode laser facet subject to back-irradiance. By determining the temperature rise in the active region (ΔΤAR) at different diode laser optical powers, back-irradiance reflectance levels, and back-irradiance spot locations, we find that ΔΤAR increases by nearly a factor of three when the back-irradiance spot is centered in the absorbing substrate approximately 5 μm away from the active region, a distance roughly equal to half of the back-irradiance spot FWHM (9 μm). This corroborates prior work studying the relationship between the back-irradiance spot location and catastrophic optical damage, suggesting a strong thermal basis for reduced laser lifetime in the presence of back-irradiance for diode lasers fabricated on absorbing substrates.

  16. Combination of nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy as a novel therapeutic application to manage the pain and treat many clinical conditions

    Science.gov (United States)

    Halasa, Salaheldin; Dickinson, Eva

    2014-02-01

    From hypertension to diabetes, cancer to HIV, stroke to memory loss and learning disorders to septic shock, male impotence to tuberculosis, there is probably no pathological condition where nitric oxide does not play an important role. Nitric oxide is an analgesic, immune-modulator, vasodilator, anti-apoptotic, growth modulator, angiogenetic, anti-thrombotic, anti-inflammatory and neuro-modulator. Because of the above actions of nitric oxide, many clinical conditions associated with abnormal Nitric oxide (NO) production and bioavailability. Our novel therapeutic approach is to restore the homeostasis of nitric oxide and replace the lost cells by combining nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy.

  17. Laserterapia de baixa intensidade na expressão de colágeno após lesão muscular cirúrgica Low-level laser therapy in the expression of collagen after muscular surgical injury

    Directory of Open Access Journals (Sweden)

    Flávia Fonseca Moreira

    2011-03-01

    Full Text Available A laserterapia é um procedimento utilizado em larga escala nas lesões musculoesqueléticas, devido as suas diversas propriedades, antiinflamatórias, cicatrizantes entre outras. Além disso, há tipos distintos de aparelhos de laser. Mesmo com os diversos modelos experimentais existentes na literatura, não há um consenso sobre a faixa de utilização, bem como o tipo de laser que promove melhor reparo no tecido muscular. Este estudo visa analisar os efeitos da laserterapia de baixa intensidade na expressão de colágeno após lesão muscular. Camundongos Swiss albinos (n=18 foram submetidos à lesão muscular cirúrgica e divididos em dois grupos, controle (C e teste (T. Os animais foram submetidos a uma irradiação diária de 5 J/cm² pelos lasers AsGaAl 830 nm e AsGa 904 nm e, em diferentes tempos de sacrifício (7 e 14 dias. Os resultados não demonstraram diferença estatística significativa na expressão de colágeno em ambos os grupos analisados. Contudo, os dados apontam que a dose de 5 J/cm² do laser AsGa 904 nm promoveu maior deposição de fibras colágenas após 14 dias de tratamento, sugerindo que a terapia seja efetiva na síntese de colágeno. Outros estudos experimentais, em humanos, devem ser propostos para maiores inferências sobre os resultados do laser no tratamento da lesão muscular.The laser therapy is a procedure utilized at long scale in the musculoskeletal injuries, due its anti-inflammatory and reparatory proprieties and others. Besides, there are differents types of laser equipments. Despites with the many experimental models at literature, there is no consensus about the range of application as well as the type of laser that promove of the best repair in muscular tissue. The aim of this study is to analyze the effects of the low level laser therapy in the expression of collagen after muscular injury. Mice Swiss albinos (n=18 were subjected to the muscular surgical injury and separated in two groups, control (C

  18. Evaluation of adjunctive effect of low-level laser Therapy on pain, swelling and trismus after surgical removal of impacted lower third molar: A double blind randomized clinical trial.

    Science.gov (United States)

    Farhadi, Farrokh; Eslami, Hosein; Majidi, Alireza; Fakhrzadeh, Vahid; Ghanizadeh, Milad; KhademNeghad, Sahar

    2017-09-30

    Wisdom teeth remains impacted in the jaw due to several reasons and surgery of impacted wisdom teeth is one of the most common surgeries in dental clinics. Pain, swelling and trismus are the common complications after this surgery which affect quality of life. In articles, various methods are introduced to control immediate inflammatory-response associated with third-molar surgery. The aim of this study is to evaluate the adjunctive effect of low-level laser Therapy on pain, swelling and trismus after surgical removal of impacted lower third molar. This double-blind randomized controlled trial (RCT) was conducted on two groups of 24 patients (age range of 18-35) that had referred to surgical ward of Faculty of Dentistry, Tabriz University of Medical Sciences for surgery of their mandibular third molar(2015-16). All the subjects were systemically healthy and had at least one impacted mandibular third molar. After surgery, in experimental group, the laser was applied intraorally (inside the tooth socket) and extraorally (at the insertion point of the masseter muscle) immediately after surgery in contact with the target area for 25 seconds each. The laser energy was 2.5 J per area with an energy density of 5 J/ cm 2 at the surface of the probe (spot size= 0.5 cm 2 ). In the other group, as the control group, it was pretended to radiate. Trismus, pain, and swelling were evaluated on the first and seventh days after surgery. The obtained data were evaluated using SPSS 16 software and independent samples T-test. In the group where LLLT had been used, P> 0.05 was calculated for pain, swelling, and trismus on days 1 and 7 after surgery that was not statistically significant. Under limitations of this study, using low-power laser with mentioned parameters, clinically reduces pain, swelling and trismus after surgical removal of impacted mandibular wisdom, but not statistically significant.

  19. Charged-particle acceleration through laser irradiation of thin foils at Prague Asterix Laser System

    International Nuclear Information System (INIS)

    Torrisi, Lorenzo; Cutroneo, Maria; Cavallaro, Salvatore; Musumeci, Paolo; Calcagno, Lucia; Wolowski, Jerzy; Rosinski, Marcin; Zaras-Szydlowska, Agnieszka; Ullschmied, Jiri; Krousky, Eduard; Pfeifer, Miroslav; Skala, Jiri; Velyhan, Andreiy

    2014-01-01

    Thin foils, 0.5–50 μm in thickness, have been irradiated in vacuum at Prague Asterix Laser System in Prague using 10 15–16  W cm −2 laser intensity, 1315 nm wavelength, 300 ps pulse duration and different focal positions. Produced plasmas from metals and polymers films have been monitored in the forward and backward directions. Ion and electron accelerations have been investigated by using Thomson parabola spectrometer, x-ray streak camera, ion collectors and SiC semiconductor detectors, the latter employed in time-of-flight configuration. Ion acceleration up to about 3 MeV per charge state was measured in the forward direction. Ion and electron emissions were detected at different angles as a function of the irradiation conditions. (paper)

  20. Investigation of field emission properties of laser irradiated tungsten

    International Nuclear Information System (INIS)

    Akram, Mahreen; Bashir, Shazia; Hayat, Asma; Mahmood, Khaliq; Jalil, Sohail Abdul; Rafique, Muhammad Shahid

    2018-01-01

    Nd:YAG laser irradiation of Tungsten (W) has been performed in air at atmospheric pressure for four laser fluences ranging from 130 to 500 J/cm 2 . Scanning electron microscope analysis revealed the formation of micro and nanoscale surface features including cones, grains, mounds and pores. Field emission (FE) studies have been performed in a planar diode configuration under ultra-high vacuum conditions by recording I-V characteristics and plotting corresponding electric field (E) versus emission current density (J). The Fowler-Nordheim (FN) plots are found to be linear confirming the quantum mechanical tunneling phenomena for the structured targets. The irradiated samples at different fluences exhibit a turn-on field, field enhancement factor β and a maximum current density ranging from 5 to 8.5 V/μm, 1300 to 3490 and 107 to 350 μA/cm 2 , respectively. The difference in the FE properties is attributed to the variation in the nature and density of the grown structures at different fluences. (orig.)

  1. Evolution of Oxygen Deficiency Center on Fused Silica Surface Irradiated by Ultraviolet Laser and Posttreatment

    Directory of Open Access Journals (Sweden)

    Hai-Bing Lü

    2014-01-01

    Full Text Available Evolution of oxygen deficiency centers (ODCs on a fused silica surface irradiated using a 355 nm ultraviolet (UV laser beam in both vacuum and atmospheric conditions was quantitatively studied using photoluminescence and X-ray photoelectron spectroscopy. When the fusedsilica surface was exposed to the UV laser in vacuum, the laser damage threshold was decreased whereas the concentration of the ODCs was increased. For the fuse silica operated under the high power lasers, creation of ODCs on their surface resulted from the UV laser irradiation, and this is more severe in a high vacuum. The laser fluence and/or laser intensity have significant effects on the increase of the ODCs concentration. The ODCs can be effectively repaired using postoxygen plasma treatment and UV laser irradiation in an excessive oxygen environment. Results also demonstrated that the “gain” and “loss” of oxygen at the silica surface is a reversible and dynamic process.

  2. Multipulse nanosecond laser irradiation of silicon for the investigation of surface morphology and photoelectric properties

    Science.gov (United States)

    Sardar, Maryam; Chen, Jun; Ullah, Zaka; Jelani, Mohsan; Tabassum, Aasma; Cheng, Ju; Sun, Yuxiang; Lu, Jian

    2017-12-01

    We irradiate the single crystal boron-doped silicon (Si) with different number of laser pulses at constant fluence (7.5 J cm-2) in ambient air using Nd:YAG laser and examine its surface morphology and photoelectric properties in details. The results obtained from optical micrographs reveal the increase in heat affected zone (HAZ) and melted area of laser irradiated Si with increasing number of laser pulses. The SEM micrographs evidence the formation of various surface morphologies like laser induced periodic surface structures, crater, microcracks, clusters, cavities, pores, trapped bubbles, nucleation sites, micro-bumps, redeposited material and micro- and nano-particles on the surface of irradiated Si. The surface profilometry analysis informs that the depth of crater is increased with increase in number of incident laser pulses. The spectroscopic ellipsometry reveals that the multipulse irradiation of Si changes its optical properties (refractive index and extinction coefficient). The current-voltage (I-V) characteristic curves of laser irradiated Si show that although the multipulse laser irradiation produces considerable number of surface defects and damages, the electrical properties of Si are well sustained after the multipulse irradiation. The current findings suggest that the multipulse irradiation can be an effective way to tune the optical properties of Si for the fabrication of wide range of optoelectronic devices.

  3. Effect of laser-plasma X-ray irradiation on crystallization of amorphous silicon film by excimer laser annealing

    International Nuclear Information System (INIS)

    Matsuo, Naoto; Uejukkoku, Kazuya; Heya, Akira; Takanashi, Yasuyuki; Amano, Sho; Miyamoto, Shuji; Mochizuki, Takayasu

    2007-01-01

    The effect of laser plasma soft X-ray (LPX) irradiation on crystallization by excimer laser annealing (ELA) was investigated at low ELA energy densities. The crystalline fraction at energy densities of 50 and 60 mJ/cm 2 for LPX followed by ELA is nearly equal to that at 80 to 100 mJ/cm 2 for the ELA method with non-LPX irradiation. The results obtained indicate that LPX irradiation before ELA reduces the critical energy density for the start of crystallization. The combined method of LPX irradiation and ELA will enable us to realize a low-temperature process for ELA crystallization. (author)

  4. Simulation analysis of impulse characteristics of space debris irradiated by multi-pulse laser

    Science.gov (United States)

    Lin, Zhengguo; Jin, Xing; Chang, Hao; You, Xiangyu

    2018-02-01

    Cleaning space debris with laser is a hot topic in the field of space security research. Impulse characteristics are the basis of cleaning space debris with laser. In order to study the impulse characteristics of rotating irregular space debris irradiated by multi-pulse laser, the impulse calculation method of rotating space debris irradiated by multi-pulse laser is established based on the area matrix method. The calculation method of impulse and impulsive moment under multi-pulse irradiation is given. The calculation process of total impulse under multi-pulse irradiation is analyzed. With a typical non-planar space debris (cube) as example, the impulse characteristics of space debris irradiated by multi-pulse laser are simulated and analyzed. The effects of initial angular velocity, spot size and pulse frequency on impulse characteristics are investigated.

  5. Measurements of three dimensional residual stress distribution on laser irradiated spot

    International Nuclear Information System (INIS)

    Tanaka, Hirotomo; Akita, Koichi; Ohya, Shin-ichi; Sano, Yuji; Naito, Hideki

    2004-01-01

    Three dimensional residual stress distributions on laser irradiated spots were measured using synchrotron radiation to study the basic mechanism of laser peening. A water-immersed sample of high tensile strength steel was irradiated with Q-switched and frequency-doubled Nd:YAG laser. The residual stress depth profile of the sample was obtained by alternately repeating the measurement and surface layer removal by electrolytic polishing. Tensile residual stresses were observed on the surface of all irradiated spots, whereas residual stress changed to compressive just beneath the surface. The depth of compressive residual stress imparted by laser irradiation and plastic deformation zone increased with increasing the number of laser pulses irradiated on the same spot. (author)

  6. Femtosecond laser irradiation of the fluorescent molecules-loaded poly(lactic-co-glycolic acid)

    Science.gov (United States)

    Umemoto, Taiga; Shibata, Akimichi; Terakawa, Mitsuhiro

    2017-09-01

    Molecular release from scaffolds is desired for tailoring cell-compatible tissue engineering. Several methods have been proposed to control molecular release, such as annealing, plasma treatment, and laser processing. In this study, we describe the alteration of Rhodamine B (RhB)-loaded poly(lactic-co-glycolic acid) (PLGA) after femtosecond laser irradiation, which was evaluated on the basis of the water absorption and mass remaining. Fluorescence measurement of released RhB molecules revealed the acceleration of the molecular release upon 400-nm laser irradiation, whereas 800-nm laser irradiation did not induce a comparable degree of change compared with non-irradiated samples. The result of the water absorption measurement indicates that the large amount of water absorption of 400-nm laser-irradiated PLGA sample may accelerate the diffusion of the loaded molecules through absorbing water, which resulted in the faster molecular release.

  7. ZnO synthesized in air by fs laser irradiation on metallic Zn thin films

    Science.gov (United States)

    Esqueda-Barrón, Y.; Herrera, M.; Camacho-López, S.

    2018-05-01

    We present results on rapid femtosecond laser synthesis of nanostructured ZnO. We used metallic Zn thin films to laser scan along straight tracks, until forming nanostructured ZnO. The synthesis dependence on laser irradiation parameters such as the per pulse fluence, integrated fluence, laser scan speed, and number of scans were explored carefully. SEM characterization showed that the morphology of the obtained ZnO is dictated by the integrated fluence and the laser scan speed; micro Raman and XRD results allowed to identify optimal laser processing conditions for getting good quality ZnO; and cathodoluminescence measurements demonstrated that a single laser scan at high per pulse laser fluence, but a medium integrated laser fluence and a medium laser scan speed favors a low density of point-defects in the lattice. Electrical measurements showed a correlation between resistivity of the laser produced ZnO and point-defects created during the synthesis. Transmittance measurements showed that, the synthesized ZnO can reach down to the supporting fused silica substrate under the right laser irradiation conditions. The physical mechanism for the formation of ZnO, under ultrashort pulse laser irradiation, is discussed in view of the distinct times scales given by the laser pulse duration and the laser pulse repetition rate.

  8. Low power laser irradiation does not affect the generation of signals in a sensory receptor

    Energy Technology Data Exchange (ETDEWEB)

    Lundeberg, T.; Zhou, J.

    1989-01-01

    The effect of low power Helium-Neon (He-Ne) and Gallium-Arsenide (Ga-As) laser on the slowly adapting crustacean stretch receptor was studied. The results showed that low power laser irradiation did not affect the membrane potential of the stretch receptor. These results are discussed in relation to the use of low power laser irradiation on the skin overlaying acupuncture points in treatment of pain syndrome.

  9. Shield gas induced cracks during nanosecond-pulsed laser irradiation of Zr-based metallic glass

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hu; Noguchi, Jun; Yan, Jiwang [Keio University, Department of Mechanical Engineering, Faculty of Science and Technology, Yokohama (Japan)

    2016-10-15

    Laser processing techniques have been given increasing attentions in the field of metallic glasses (MGs). In this work, effects of two kinds of shield gases, nitrogen and argon, on nanosecond-pulsed laser irradiation of Zr-based MG were comparatively investigated. Results showed that compared to argon gas, nitrogen gas remarkably promoted the formation of cracks during laser irradiation. Furthermore, crack formation in nitrogen gas was enhanced by increasing the peak laser power intensity or decreasing the laser scanning speed. X-ray diffraction and micro-Raman spectroscopy indicated that the reason for enhanced cracks in nitrogen gas was the formation of ZrN. (orig.)

  10. Microsized structures assisted nanostructure formation on ZnSe wafer by femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Wang, Shutong; Feng, Guoying; Zhou, Shouhuan

    2014-01-01

    Micro/nano patterning of ZnSe wafer is demonstrated by femtosecond laser irradiation through a diffracting pinhole. The irradiation results obtained at fluences above the ablation threshold are characterized by scanning electron microscopy. The microsized structure with low spatial frequency has a good agreement with Fresnel diffraction theory. Laser induced periodic surface structures and laser-induced periodic curvelet surface structures with high spatial frequency have been found on the surfaces of microsized structures, such as spikes and valleys. We interpret its formation in terms of the interference between the reflected laser field on the surface of the valley and the incident laser pulse

  11. Shield gas induced cracks during nanosecond-pulsed laser irradiation of Zr-based metallic glass

    Science.gov (United States)

    Huang, Hu; Noguchi, Jun; Yan, Jiwang

    2016-10-01

    Laser processing techniques have been given increasing attentions in the field of metallic glasses (MGs). In this work, effects of two kinds of shield gases, nitrogen and argon, on nanosecond-pulsed laser irradiation of Zr-based MG were comparatively investigated. Results showed that compared to argon gas, nitrogen gas remarkably promoted the formation of cracks during laser irradiation. Furthermore, crack formation in nitrogen gas was enhanced by increasing the peak laser power intensity or decreasing the laser scanning speed. X-ray diffraction and micro-Raman spectroscopy indicated that the reason for enhanced cracks in nitrogen gas was the formation of ZrN.

  12. Ultraviolet pulsed laser irradiation of multi-walled carbon nanotubes in nitrogen atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pérez del Pino, Ángel, E-mail: aperez@icmab.es; Cabana, Laura; Tobias, Gerard [Instituto de Ciencia de Materiales de Barcelona, Consejo Superior de Investigaciones Científicas (ICMAB-CSIC), Campus UAB, 08193 Bellaterra (Spain); György, Enikö [Instituto de Ciencia de Materiales de Barcelona, Consejo Superior de Investigaciones Científicas (ICMAB-CSIC), Campus UAB, 08193 Bellaterra (Spain); National Institute for Lasers, Plasma and Radiation Physics, P. O. Box MG 36, 76900 Bucharest V (Romania); Ballesteros, Belén [ICN2—Institut Catala de Nanociencia i Nanotecnologia, Campus UAB, 08193 Bellaterra, Barcelona (Spain)

    2014-03-07

    Laser irradiation of randomly oriented multi-walled carbon nanotube (MWCNT) networks has been carried out using a pulsed Nd:YAG UV laser in nitrogen gas environment. The evolution of the MWCNT morphology and structure as a function of laser fluence and number of accumulated laser pulses has been studied using electron microscopies and Raman spectroscopy. The observed changes are discussed and correlated with thermal simulations. The obtained results indicate that laser irradiation induces very fast, high temperature thermal cycles in MWCNTs which produce the formation of different nanocarbon forms, such as nanodiamonds. Premelting processes have been observed in localized sites by irradiation at low number of laser pulses and low fluence values. The accumulation of laser pulses and the increase in the fluence cause the full melting and amorphization of MWCNTs. The observed structural changes differ from that of conventional high temperature annealing treatments of MWCNTs.

  13. Laser irradiation effects and its possible mechanisms of action on spermatozoa functions in domestic animals

    Directory of Open Access Journals (Sweden)

    S A Lone

    2017-01-01

    Full Text Available This article presents a review pertains the laser irradiation effects and its possible mechanisms of action on spermatozoa functions in domestic animals. To improve artificial insemination, laser is sensitive and cost effective technique, when compared to other conventional methods. Laser may have both positive and negative effects on spermatozoa functions. Since the effects of light are mediated by reactive oxygen species, and the levels of these reactive oxygen species following irradiating spermatozoa with laser may be responsible for determining the effects of laser on sperm. Dose of laser may be regarded as of great significance and this dosage of laser may be responsible for determining its effects on spermatozoa. Optimum dosage of laser for improving seminal attributes may vary among various species and this need to be standardized in each of them. The beneficial effects include improving sperm livability, acrosomal integrity, hypo-osmotic swelling response, mitochondrial function and computer-aided sperm analysis parameters. The increase in cytochrome c oxidase activity, ATP levels and mitochondrial membrane potential, in laser irradiated cells may be responsible for enhanced sperm quality parameters. Improving fertility with laser irradiated spermatozoa has been reported in few species like boar and need to be elaborated in other species. In conclusion laser may be regarded as an easy, cheap and time saving technology for improving artificial insemination; in addition, laser may have various potential applications in the field of reproductive biotechnology as well as in livestock farms and veterinary polyclinics.

  14. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    Churtgen, C.

    2007-01-01

    The low-level radioactivity measurements service performs measurements of alpha or beta emitters on various types of low-radioactivity samples (biological and environmental) from internal and external clients. to maintain and develop techniques concerning the measurement of low-level radioactivity of alpha and beta emitting radionuclides in environmental or biological samples; to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters and alpha-spectrometers); to support and advise the nuclear and non-nuclear industry on problems of radioactive contamination or low level radioactivity measurements; to maintain the quality assurance system according to the ISO17025 standard for which we obtained the Beltest accreditation in 1998; to assess the internal dose from occupational intakes of radionuclides for workers of the nuclear industry;

  15. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    Hurtgen, C.

    2002-01-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advise the nuclear and non-nuclear industry on problems of radioactive contamination and low-level radioactivity measurements; (4) to maintain and improve the quality assurance system according to the ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2001 are reported

  16. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    Hurtgen, C.

    2001-01-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advice the nuclear and non-nuclear industry in matters concerning radioactive contamination and/or low-level radioactivity measurements; (4) to maintain the quality assurance system according to the EN45001/ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2000 are reported

  17. Formation of laser-induced periodic surface structures on niobium by femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Pan, A.; Dias, A.; Gomez-Aranzadi, M.; Olaizola, S. M.; Rodriguez, A.

    2014-01-01

    The surface morphology of a Niobium sample, irradiated in air by a femtosecond laser with a wavelength of 800 nm and pulse duration of 100 fs, was examined. The period of the micro/nanostructures, parallel and perpendicularly oriented to the linearly polarized fs-laser beam, was studied by means of 2D Fast Fourier Transform analysis. The observed Laser-Induced Periodic Surface Structures (LIPSS) were classified as Low Spatial Frequency LIPSS (periods about 600 nm) and High Spatial Frequency LIPSS, showing a periodicity around 300 nm, both of them perpendicularly oriented to the polarization of the incident laser wave. Moreover, parallel high spatial frequency LIPSS were observed with periods around 100 nm located at the peripheral areas of the laser fingerprint and overwritten on the perpendicular periodic gratings. The results indicate that this method of micro/nanostructuring allows controlling the Niobium grating period by the number of pulses applied, so the scan speed and not the fluence is the key parameter of control. A discussion on the mechanism of the surface topology evolution was also introduced

  18. Formation of laser-induced periodic surface structures on niobium by femtosecond laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Pan, A.; Dias, A.; Gomez-Aranzadi, M.; Olaizola, S. M. [CIC microGUNE, Goiru Kalea 9 Polo Innovación Garaia, 20500 Arrasate-Mondragón (Spain); CEIT-IK4 and Tecnun, University of Navarra, Manuel Lardizábal 15, 20018 San Sebastián (Spain); Rodriguez, A. [CIC microGUNE, Goiru Kalea 9 Polo Innovación Garaia, 20500 Arrasate-Mondragón (Spain)

    2014-05-07

    The surface morphology of a Niobium sample, irradiated in air by a femtosecond laser with a wavelength of 800 nm and pulse duration of 100 fs, was examined. The period of the micro/nanostructures, parallel and perpendicularly oriented to the linearly polarized fs-laser beam, was studied by means of 2D Fast Fourier Transform analysis. The observed Laser-Induced Periodic Surface Structures (LIPSS) were classified as Low Spatial Frequency LIPSS (periods about 600 nm) and High Spatial Frequency LIPSS, showing a periodicity around 300 nm, both of them perpendicularly oriented to the polarization of the incident laser wave. Moreover, parallel high spatial frequency LIPSS were observed with periods around 100 nm located at the peripheral areas of the laser fingerprint and overwritten on the perpendicular periodic gratings. The results indicate that this method of micro/nanostructuring allows controlling the Niobium grating period by the number of pulses applied, so the scan speed and not the fluence is the key parameter of control. A discussion on the mechanism of the surface topology evolution was also introduced.

  19. Histological observation on dental hard tissue irradiated by ultrashort-pulsed laser

    Science.gov (United States)

    Uchizono, Takeyuki; Awazu, Kunio; Igarashi, Akihiro; Kato, Junji; Hirai, Yoshito

    2006-04-01

    In the field of dentistry, effectiveness of USPL irradiation is researched because USPL has less thermal side effect to dental hard tissue. In this paper, we observed morphological change and optical change of dental hard tissue irradiated by USPL for discussing the safety and effectiveness of USPL irradiation to dental hard tissues. Irradiated samples were crown enamel and root dentin of bovine teeth. Lasers were Ti:sapphire laser, which had pulse duration (P d)of 130 fsec and pulse repetition rate (f) of 1kHz and wavelength (l) of 800nm, free electron laser (FEL), which had P d of 15 μsec and f of 10Hz and wavelength of 9.6μm, and Er:YAG laser, which had P d of 250 μsec and f of 10Hz and wavelength of 2.94μm. After laser irradiation, the sample surfaces and cross sections were examined with SEM and EDX. The optical change of samples was observed using FTIR. In SEM, the samples irradiated by USPL had sharp and accurate ablation with no crack and no carbonization. But, in FEL and Er:YAG laser, the samples has rough ablation with crack and carbonization. It was cleared that the P/Ca ratio of samples irradiated by USPL had same value as non-irradiated samples. There was no change in the IR absorption spectrum between samples irradiated by USPL and non-irradiated sample. But, they of samples irradiated by FEL and Er:YAG laser, however, had difference value as non-irradiated samples. These results showed that USPL might be effective to ablate dental hard tissue without thermal damage.

  20. Manipulating the mitochondria activity in human hepatic cell line Huh7 by low-power laser irradiation

    Science.gov (United States)

    Lynnyk, Anna; Lunova, Mariia; Jirsa, Milan; Egorova, Daria; Kulikov, Andrei; Kubinová, Šárka; Lunov, Oleg; Dejneka, Alexandr

    2018-01-01

    Low-power laser irradiation of red light has been recognized as a promising tool across a vast variety of biomedical applications. However, deep understanding of the molecular mechanisms behind laser-induced cellular effects remains a significant challenge. Here, we investigated mechanisms involved in the death process in human hepatic cell line Huh7 at a laser irradiation. We decoupled distinct cell death pathways targeted by laser irradiations of different powers. Our data demonstrate that high dose laser irradiation exhibited the highest levels of total reactive oxygen species production, leading to cyclophilin D-related necrosis via the mitochondrial permeability transition. On the contrary, low dose laser irradiation resulted in the nuclear accumulation of superoxide and apoptosis execution. Our findings offer a novel insight into laser-induced cellular responses, and reveal distinct cell death pathways triggered by laser irradiation. The observed link between mitochondria depolarization and triggering ROS could be a fundamental phenomenon in laser-induced cellular responses. PMID:29541521

  1. Influence of laser shock peening on irradiation defects in austenitic stainless steels

    Science.gov (United States)

    Lu, Qiaofeng; Su, Qing; Wang, Fei; Zhang, Chenfei; Lu, Yongfeng; Nastasi, Michael; Cui, Bai

    2017-06-01

    The laser shock peening process can generate a dislocation network, stacking faults, and deformation twins in the near surface of austenitic stainless steels by the interaction of laser-driven shock waves with metals. In-situ transmission electron microscopy (TEM) irradiation studies suggest that these dislocations and incoherent twin boundaries can serve as effective sinks for the annihilation of irradiation defects. As a result, the irradiation resistance is improved as the density of irradiation defects in laser-peened stainless steels is much lower than that in untreated steels. After heating to 300 °C, a portion of the dislocations and stacking faults are annealed out while the deformation twins remain stable, which still provides improved irradiation resistance. These findings have important implications on the role of laser shock peening on the lifetime extension of austenitic stainless steel components in nuclear reactor environments.

  2. Effects of low-level laser therapy after nerve reconstruction in rat denervated soleus muscle adaptation Efeitos do laser de baixa potência após reconstrução nervosa na adaptação do músculo sóleo de rato

    Directory of Open Access Journals (Sweden)

    Marcela A Silva-Couto

    2012-08-01

    Full Text Available BACKGROUND: Peripheral nerve injury (PNI rehabilitation remains a challenge for physical therapists because PNI effects are very disabling. Low-level laser therapy (LLLT has been described as a physical resource that is able to influence enzymes called metallopeptidases (MMPs associated with extracellular matrix (ECM turnover, thus accelerating neuromuscular recovery after nerve crush injuries. However, the effects of LLLT in the treatment of severe nerve injuries and denervated slow-twitch muscles are still inconclusive. OBJECTIVES: The aim of this study was to evaluate the effects of different wavelengths and energy densities of LLLT irradiation, applied to a severe nerve injury after reconstruction, on denervated slow-twitch skeletal muscle adaptation. METHOD: Rats were submitted to a neurotmesis of the sciatic nerve followed by end-to-end neurorrhaphy. They received transcutaneous LLLT irradiation at the lesion site. The LLLT parameters were: wavelengths - 660 or 780 nm; energy densities - 10, 60 or 120 J/cm²; power - 40 mW; spot - 4 mm². Sciatic functional index (SFI, histological, morphometric, and zymographic analyses were performed. One-way ANOVA followed by Tukey's test was used (pCONTEXTUALIZAÇÃO: A reabilitaçao das lesões nervosas periféricas (LNP ainda é um desafio para a fisioterapia. A terapia com o laser de baixa potência (LBP é descrita como um recurso físico capaz de interagir com enzimas relacionadas à alteração da matrix extracelular. Denominadas metalopeptidases (MMPs, essas enzimas atuam durante a recuperação neuromuscular após LNP. No entanto, os efeitos da LBP no tratamento de músculos desnervados de contração lenta após LNP graves ainda são inconclusivos. OBJETIVO: Avaliar os efeitos de diferentes comprimentos de onda e densidades de energia de irradiação de LBP, aplicado sobre o local do nervo após LNP grave e reconstrução. MÉTODO: Ratos foram submetidos a neurotmese do nervo isquiático e

  3. SEM analysis of enamel surface treated by Er:YAG laser: influence of irradiation distance.

    Science.gov (United States)

    Souza-Gabriel, A E; Chinelatti, M A; Borsatto, M C; Pécora, J D; Palma-Dibb, R G; Corona, S A M

    2008-07-01

    Depending on the distance of laser tip to dental surface a specific morphological pattern should be expected. However, there have been limited reports that correlate the Er:YAG irradiation distance with dental morphology. To assess the influence of Er:YAG laser irradiation distance on enamel morphology, by means of scanning electron microscopy (SEM). Sixty human third molars were employed to obtain discs (approximately =1 mm thick) that were randomly assigned to six groups (n=10). Five groups received Er:YAG laser irradiation (80 mJ/2 Hz) for 20 s, according to the irradiation distance: 11, 12, 14, 16, or 17 mm and the control group was treated with 37% phosphoric acid for 15 s. The laser-irradiated discs were bisected. One hemi-disc was separated for superficial analysis without subsequent acid etching, and the other one, received the phosphoric acid for 15 s. Samples were prepared for SEM. Laser irradiation at 11 and 12 mm provided an evident ablation of enamel, with evident fissures and some fused areas. At 14, 16 and 17 mm the superficial topography was flatter than in the other distances. The subsequent acid etching on the lased-surface partially removed the disorganized tissue. Er:YAG laser in defocused mode promoted slight morphological alterations and seems more suitable for enamel conditioning than focused irradiation. The application of phosphoric acid on lased-enamel surface, regardless of the irradiation distance, decreased the superficial irregularities.

  4. Apraclonidine effects on ocular responses to YAG laser irradiation to the rabbit iris

    International Nuclear Information System (INIS)

    Sugiyama, K.; Kitazawa, Y.; Kawai, K.

    1990-01-01

    Apraclonidine (p-aminoclonidine) ophthalmic solution effectively reduces the rise in intraocular pressure (IOP) following anterior segment laser surgery. We tested the effect of topical 0.5% apraclonidine on intraocular pressure and on protein and prostaglandin (PG) E2 concentrations in aqueous humor following Q-switched Nd:YAG laser irradiation to the iris of albino rabbits, at an energy level of 2 to 200 mJ. IOP was measured prior to and for 24 hr after irradiation. Aqueous humor was withdrawn before and 1 hr after laser irradiation for determining protein (Lowry method) and PGE2 (radioimmunoassay). Four to seven rabbits were used for each experiment. The increase in IOP and protein concentration following laser irradiation was demonstrated to be dependent on the amount of laser energy. Apraclonidine completely abolished the IOP rise, and significantly reduced the elevation of protein content. Apraclonidine failed to affect the increase in PGE2

  5. Oscillating flux in petroleum emulsions irradiated with laser; Flujo oscilatorio en emulsiones de petroleo irradiadas con laser

    Energy Technology Data Exchange (ETDEWEB)

    Costa, G. Da; Parra, J.E.; Mosqueda, F. [Departamento de Fisica, Laboratorio de Optica y Fluidos, Universidad Simon Bolivar, Apartado Postal 89000, Caracas 1080-A, (Venezuela)]. e-mail: german@usb.ve; Romanelli, A.; Sicardi-Schifino, A. [Instituto de Fisica, Facultad de Ingenieria, Julio Herrera y Reissig 565, Montevideo, (Uruguay)]. e-mail alejo@fing.edu.uy

    2003-07-01

    Oil-in-water emulsions are irradiated with a Cw laser beam. A floating oil layer grows up in the water free surface. Laser-induced wave propagation in the oil layer gives rise to space-time self-modulation of the reflected light beam. A theoretical model explains main features of observed phenomena. (Author)

  6. Effects of low-level laser therapy after nerve reconstruction in rat denervated soleus muscle adaptation Efeitos do laser de baixa potência após reconstrução nervosa na adaptação do músculo sóleo de rato

    OpenAIRE

    Marcela A Silva-Couto; Davilene Gigo-Benato; Carla R. Tim; Nivaldo A. Parizotto; Tania F. Salvini; Thiago L. Russo

    2012-01-01

    BACKGROUND: Peripheral nerve injury (PNI) rehabilitation remains a challenge for physical therapists because PNI effects are very disabling. Low-level laser therapy (LLLT) has been described as a physical resource that is able to influence enzymes called metallopeptidases (MMPs) associated with extracellular matrix (ECM) turnover, thus accelerating neuromuscular recovery after nerve crush injuries. However, the effects of LLLT in the treatment of severe nerve injuries and denervated slow-twit...

  7. Comparing the effects of exercise program and low-level laser therapy with exercise program and polarized polychromatic non-coherent light (bioptron light) on the treatment of lateral elbow tendinopathy.

    Science.gov (United States)

    Stasinopoulos, Dimitrios; Stasinopoulos, Ioannis; Pantelis, Manias; Stasinopoulou, Kalliopi

    2009-06-01

    The use of low-level laser therapy (LLLT) and polarized polychromatic non-coherent light as supplements to an exercise program has been recommended for the management of lateral elbow tendinopathy (LET). To investigate whether an exercise program supplemented with LLLT is more successful than an exercise program supplemented with polarized polychromatic non-coherent light in treating LET. Patients with unilateral LET for at least 4 wk were sequentially allocated to receive either an exercise program with LLLT or an exercise program with polarized polychromatic non-coherent light. The exercise program consisted of eccentric and static stretching exercises of wrist extensors. In the LLLT group a 904-nm Ga-As laser was used in continuous mode, and the power density was 130 mW/cm(2), and the dose was 0.585 J/point. In the group receiving polarized polychromatic non-coherent light the Bioptron 2 was used to administer the dose perpendicularly to the lateral epicondyle at three points at an operating distance of 5-10 cm for 6 min at each position. The outcome measures were pain and function and were evaluated at baseline, at the end of the treatment (week 4), and 3 mo after the end of treatment (week 16). Fifty patients met the inclusion criteria. At the end of treatment there was a decline in pain and a rise in function in both groups compared with baseline (p 0.0005 on the independent t-test). The results suggest that the combination of an exercise program with LLLT or polarized polychromatic non-coherent light is an adequate treatment for patients with LET. Further research to establish the relative and absolute effectiveness of such a treatment approach is needed.

  8. Effect of laser pulse parameters on the size and fluorescence of nanodiamonds formed upon pulsed-laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Peikang [School of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Hu, Shengliang, E-mail: hsliang@yeah.net [Key Laboratory of Instrumentation Science and Dynamic Measurement (North University of China), Ministry of Education, National Key Laboratory Science and Technology on Electronic Test and Measurement, Taiyuan 030051 (China); School of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Zhang, Taiping; Sun, Jing [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Cao, Shirui [School of Materials Science and Engineering, North University of China, Taiyuan 030051 (China)

    2010-07-15

    The size of nanodiamonds formed upon laser irradiation could be easily controlled over simply adjusting laser pulse parameters. The stable size and structure of nanodiamonds were mostly determined by laser power density and pulse width. Both large nanodiamonds with multiply twinning structure (MTS) and small nanodiamonds with single crystalline structure (SCS) emitted strong visible light after surface passivation, and their fluorescence quantum yield (QY) was 4.6% and 7.1%, respectively.

  9. Effect of laser pulse parameters on the size and fluorescence of nanodiamonds formed upon pulsed-laser irradiation

    International Nuclear Information System (INIS)

    Bai, Peikang; Hu, Shengliang; Zhang, Taiping; Sun, Jing; Cao, Shirui

    2010-01-01

    The size of nanodiamonds formed upon laser irradiation could be easily controlled over simply adjusting laser pulse parameters. The stable size and structure of nanodiamonds were mostly determined by laser power density and pulse width. Both large nanodiamonds with multiply twinning structure (MTS) and small nanodiamonds with single crystalline structure (SCS) emitted strong visible light after surface passivation, and their fluorescence quantum yield (QY) was 4.6% and 7.1%, respectively.

  10. Improving the bulk laser-damage resistance of KDP by baking and pulsed-laser irradiation

    International Nuclear Information System (INIS)

    Swain, J.E.; Stokowski, S.E.; Milam, D.; Rainer, F.

    1981-01-01

    Isolated bulk damage centers are produced when KDP crystals are irradiated by 1-ns 1064-nm pulses. We have tested about 100 samples and find the median threshold to be 7 J/cm 2 when the samples are irradiated only once at each test volume (1-on-1 tests). The median threshold increased to 11 J/cm 2 when the test volumes were first subjected to subthreshold laser irradiation (n-on-1 tests). We baked several crystals at temperatures from 110 to 165 0 C and remeasured their thresholds. Baking increased thresholds in some crystals, but did not change thresholds of others. The median threshold of baked crystals ranged from 8 to 10 J/cm 2 depending on the baking temperature. In crystals that had been baked, subthreshold irradiation produced a large change in the bulk damage threshold, and reduced the volume density of damage centers relative to the density observed in unbaked crystals. The data are summarized in the table

  11. [Effects of Nd: YAG laser irradiation on the root surfaces and adhesion of Streptococcus mutans].

    Science.gov (United States)

    Yuanhong, Li; Zhongcheng, Li; Mengqi, Luo; Daonan, Shen; Shu, Zhang; Shu, Meng

    2016-12-01

    This study aimed to evaluate the effects of treatment with different powers of Nd: YAG laser irradiation on root surfaces and Streptococcus mutans (S. mutans) adhesion. Extracted teeth because of severe periodontal disease were divided into the following four groups: control group, laser group 1, laser group 2, and laser group 3. After scaling and root planning, laser group 1, laser group 2, and laser group 3 were separately treated with Nd: YAG laser irradiation (4/6/8 W, 60 s); however, the control group did not receive the treatment. Scanning electron microscopy (SEM) was used to determine the morphology. S. mutans were cultured with root slices from each group. Colony forming unit per mL (CFU·mL⁻¹) was used to count and compare the amounts of bacteria adhesion among groups. SEM was used to observe the difference of bacteria adhesion to root surfaces between control group (scaling) and laser group 2 (6 W, 60 s), thereby indicating the different bacteria adhesions because of different treatments. Morphology alterations indicated that root surfaces in control group contain obvious smear layer, debris, and biofilm; whereas the root surfaces in laser group contain more cracks with less smear layer and debris. The bacteria counting indicated that S. mutans adhesion to laser group was weaker than that of control group (P0.05) was observed. Morphology alterations also verified that S. mutans adhesion to laser group 2 (6 W, 60 s) was weaker than that of control group (scaling). This study demonstrated that Nd: YAG laser irradiation treatment after scaling can reduce smear layer, debris, and biofilm on the root surfaces as compared with conventional scaling. The laser treatment reduces the adhesion of S. mutans as well. However, Nd: YAG laser irradiation can cause cracks on the root surfaces. In this experiment, the optimum laser power of 6 W can thoroughly remove the smear layer and debris, as well as relatively improve the control of thermal damagee.

  12. Low-level therapy in ophthalmology

    Science.gov (United States)

    Pankov, O. P.

    1999-07-01

    Extremely slow introduction of low-level laser therapy into the practice of ophthalmologists is restricted by the lack of good methodological recommendation and modern equipment adopted to the needs of ophthalmology. The most perspective is considered to be further improvement of the methods and the elaboration of the medical equipment, working in several wave bands, combined with magnetotherapy and working with the use of various modes of the modulation of the intensity of the luminous flux. It may be asserted that unlike the mode of continuous radiation, in some cases, the effectiveness of the treatment increases when the modulated light with the frequency of one to a few tens HZ is used. Moreover, the methods are being elaborated, when the modulation frequency of laser light and the biorhythms of man physiologic parameters are synchronized. Very perspective seems the computerization of the treatment process with the simultaneous electrophysiological control of the condition of visual functions.

  13. Effects of low-energy laser irradiation on the distalization velocity during experimental canine tooth movement in humans: 'comparative clinical study'

    International Nuclear Information System (INIS)

    Cruz, Delma Rebelo

    2003-01-01

    This research investigated the effects of low level laser therapy (LLLT) upon the velocity of canine tooth movement and consequently bone remodeling. A total of eleven patients were treated with a 780 nm diode laser. One side of the upper arcade was considered control group and was not irradiated but received mechanical activation every thirty days. The opposite side received the same mechanical activation but was also irradiated at days 0, 3, 7 and 14 of each month. Data of the biometrical progress were taken on both sides on days 3,7,14,21 and 30 of each month. The results indicate that all patients showed significant acceleration of the distalization velocity on the side treated with LLLT when compared to the control. (author)

  14. Acute effects of pulsed-laser irradiation on the arterial wall

    Science.gov (United States)

    Nakamura, Fumitaka; Kvasnicka, Jan; Lu, Hanjiang; Geschwind, Herbert J.; Levame, Micheline; Bousbaa, Hassan; Lange, Francoise

    1992-08-01

    Pulsed laser coronary angioplasty with an excimer or a holmium-yttrium-aluminum-garnet (Ho:YAG) laser may become an alternative treatment for patients with coronary artery disease. However, little is known about its acute consequences on the normal arterial wall. This study was designed to examine the acute histologic consequences of these two pulsed lasers on the arterial wall of normal iliac arteries in rabbits. Irradiation with each laser was performed in 15 normal iliac sites on eight male New Zealand white rabbits. The excimer laser was operated at 308 nm, 25 Hz, 50 mJ/mm2/pulse, and 135 nsec/pulse and the Ho:YAG laser was operated at 2.1 micrometers , 3/5 Hz, 400 mJ/pulse, and 250 microsecond(s) ec/pulse. The excimer and Ho:YAG laser were coupled into a multifiber wire-guided catheter of 1.4 and 1.5 mm diameter, respectively. The sites irradiated with excimer or Ho:YAG laser had the same kinds of histologic features, consisting of exfoliation of the endothelium, disorganization of internal elastic lamina, localized necrosis of vascular smooth muscle cells, and fissures in the medial layer. However, the sites irradiated with excimer laser had lower grading scores than those irradiated with Ho:YAG laser (p vascular injury.

  15. Small-scale heat detection using catalytic microengines irradiated by laser

    Science.gov (United States)

    Liu, Zhaoqian; Li, Jinxing; Wang, Jiao; Huang, Gaoshan; Liu, Ran; Mei, Yongfeng

    2013-01-01

    We demonstrate a novel approach to modulating the motion speed of catalytic microtubular engines via laser irradiation/heating with regard to small-scale heat detection. Laser irradiation on the engines leads to a thermal heating effect and thus enhances the engine speed. During a laser on/off period, the motion behaviour of a microengine can be repeatable and reversible, demonstrating a regulation of motion speeds triggered by laser illumination. Also, the engine velocity exhibits a linear dependence on laser power in various fuel concentrations, which implies an application potential as local heat sensors. Our work may hold great promise in applications such as lab on a chip, micro/nano factories, and environmental detection.We demonstrate a novel approach to modulating the motion speed of catalytic microtubular engines via laser irradiation/heating with regard to small-scale heat detection. Laser irradiation on the engines leads to a thermal heating effect and thus enhances the engine speed. During a laser on/off period, the motion behaviour of a microengine can be repeatable and reversible, demonstrating a regulation of motion speeds triggered by laser illumination. Also, the engine velocity exhibits a linear dependence on laser power in various fuel concentrations, which implies an application potential as local heat sensors. Our work may hold great promise in applications such as lab on a chip, micro/nano factories, and environmental detection. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32494f

  16. Low-level radioactive waste

    International Nuclear Information System (INIS)

    McLaren, L.H.

    1983-03-01

    This bibliography contains information on low-level radioactive waste included in the Department of Energy's Energy Data Base for January through December 1982. The abstracts are grouped by subject category as shown in the table of contents. Entries in the subject index also facilitate access by subject, e.g., Low-Level Radioactive Wastes/Transport. Within each category the arrangement is by report number for reports, followed by nonreports in reverse chronological order. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each proceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 492 references

  17. Low level photoneutron detection equipment

    International Nuclear Information System (INIS)

    Ji Changsong; Zhang Yuqin; Li Yuansui

    1991-01-01

    A low level photoneutron detection equipment has been developed. The photoneutrons produced by interaction of 226 Ra gamma quanta and deutron (D) target are detected with n-n discrimination detector made up of 3 He proportional counter array. The D-content information in the target can be obtained from the measured photoneutron counts. The equipment developed is mainly used for nondestructive D-content measurement of D-devices

  18. Low- and high-dose laser irradiation effects on cell migration and destruction

    Science.gov (United States)

    Layton, Elivia; Gallagher, Kyra A.; Zukerman, Sara; Stevens, Brianna; Zhou, Feifan; Liu, Hong; Chen, Wei R.

    2018-02-01

    Metastases are the cause of more than 90 percent of cancer-related deaths. Current treatment methods, including chemotherapy, radiation, and surgery, fail to target the metastases effectively. One potential treatment for metastatic cancer is laser immunotherapy (LIT). LIT combines the use of a photothermal laser with an immunoadjuvant, Glycated Chitosan (GC). GC combined with single-walled carbon nanotubes (SWNTs) has proven to be a viable alternative to traditional cancer treatment methods, when under irradiation of laser with appropriate wavelength. In this study, the effects of low dose and high dose laser irradiation on metastatic pancreatic cancer cell migration were observed. It was found that low dose irradiation increased the migration rate, but the high dose irradiation significantly decreased the migration rate of the cancer cells. When using LIT, the goal is to kill tumor cells and to prompt the correct immune response. If the tumor were irradiated with a low dose, it would promote metastasis. If the dose of irradiation were too high, it would destroy the entire tumor and the immune response would not recognize the tumor. Therefore, the laser dose plays an important role in LIT, particularly when using SWNT as light absorbing agent. Our results from this study will delineate the optimal laser irradiation dose for destroying tumor cells and at the same time preserve and release tumor antigens as a precursor of antitumor immune response.

  19. Effect of semiconductor GaAs laser irradiation on pain perception in mice

    Energy Technology Data Exchange (ETDEWEB)

    Zarkovic, N.; Manev, H.; Pericic, D.; Skala, K.; Jurin, M.; Persin, A.; Kubovic, M.

    1989-01-01

    The influence of subacute exposure (11 exposures within 16 days) of mice to the low power (GaAs) semiconductive laser-stimulated irradiation on pain perception was investigated. The pain perception was determined by the latency of foot-licking or jumping from the surface of a 53 degrees C hot plate. Repeated hot-plate testing resulted in shortening of latencies in both sham- and laser-irradiated mice. Laser treatment (wavelength, 905 nm; frequency, 256 Hz; irradiation time, 50 sec; pulse duration, 100 nsec; distance, 3 cm; peak irradiance, 50 W/cm2 in irradiated area; and total exposure, 0.41 mJ/cm2) induced further shortening of latencies, suggesting its stimulatory influence on pain perception. Administration of morphine (20 mg/kg) prolonged the latency of response to the hot plate in both sham- and laser-irradiated mice. This prolongation tended to be lesser in laser-irradiated animals. Further investigations are required to elucidate the mechanism of the observed effect of laser.

  20. In Vitro Evaluation of Dentin Hydraulic Conductance After 980 nm Diode Laser Irradiation.

    Science.gov (United States)

    Rizzante, Fabio A P; Maenosono, Rafael M; Duarte, Marco A H; Furuse, Adilson Y; Palma-Dibb, Regina G; Ishikiriama, Sérgio K

    2016-03-01

    Dentin hypersensitivity treatments are based on the physical obliteration of the dentinal tubules to reduce hydraulic conductance. The aim of the present study is to evaluate the hydraulic conductance of bovine root dentin after irradiation with a 980-nm diode laser, with or without associated fluoride varnish. Sixty bovine root dentin specimens were divided into six groups (n = 10 in each group): G1, G3, and G5 (0.5 W, 0.7 W, and 1 W diode laser, respectively); G2, G4, and G6 (fluoride varnish application + 0.5 W, 0.7 W, and 1 W diode laser, respectively). The dentin hydraulic conductance was evaluated at four time periods with a fluxmeter: 1) with smear layer, 2) after 37% phosphoric acid etching, 3) after the treatments, and 4) after 6% citric acid challenge. After the dentinal fluid flow measurements, specimens were also evaluated for mineral composition using energy dispersive X-ray spectroscopy (EDS). Analysis demonstrated a better result with increased irradiation power (P diode laser irradiation was associated with the application of fluoride varnish (P laser irradiation, the 1 W group was superior when compared with the 0.5 W and 0.7 W irradiated groups immediately after treatment (P laser treatments. Laser irradiation of exposed dentin promoted significant reduction in the dentin hydraulic conductance, mainly with higher energy densities and association with fluoride varnish.

  1. Bond strength of an adhesive system irradiated with Nd:YAG laser in dentin treated with Er:YAG laser

    International Nuclear Information System (INIS)

    Malta, D A M P; De Andrade, M F; Costa, M M; Lizarelli, R F Z; Pelino, J E P

    2008-01-01

    The purpose of this in vitro study was to verify through micro tensile bond test the bond strength of an adhesive system irradiated with Nd:YAG laser in dentine previously treated with Er:YAG laser. Twenty caries free extracted human third molars were used. The teeth were divided in four experimental groups (n = 5): (G1) control group; (G2) irradiation of the adhesive system with the Nd:YAG laser; (G3) dentin treatment with Er:YAG laser; (G4) dentin treatment with Er:YAG laser followed by the irradiation of the adhesive system with Nd:YAG laser. The Er:YAG laser fluency parameter for the dentin treatment was of 60 J/cm 2 . The adhesive system was irradiated with the Nd:YAG laser with fluency of 100 J/cm 2 . Dental restorations were performed with Adper Single Bond 2/Z250. One tooth from each group was prepared for the evaluation of the adhesive interface under SEM and bond failure tests were also performed and evaluated. The statistical analysis showed statistical significant difference between the groups G1 and G3, G1 and G4, G2 and G3, and G2 and G4; and similarity between the groups G1 and G2, and G3 and G4. The adhesive failures were predominant in all the experimental groups. The SEM analysis showed an adhesive interface with features confirming the results of the mechanical tests. The Nd:YAG laser on the adhesive system did not influence the bond strength in dentin treated or not with the Er:YAG laser

  2. Evaluation of the role of laser bio stimulation on skin and liver of gamma-irradiated mice

    International Nuclear Information System (INIS)

    Salem, E.S.

    2007-01-01

    Low level laser therapy (LLLT) is used in different medical fields due to its therapeutic effects on reparative processes, pain relief and bio stimulation (Castro-e-silva et al., 2003). The present study aimed at evaluating the therapeutic efficacy of He-Ne laser in stimulating the reparative processes after whole body irradiation of mice using a sublethal dose (5 Gy) of gamma rays. Two vital organs were studied, a radio-sensitive one (the skin) as well as a relatively radio-resistant one (the liver) . During the course of the present work, some biochemical parameters as well as histopathological changes in the skin and liver tissues induced by whole body gamma ionizing radiation were studied. Female mice (240) were used and divided into 6 groups and laser therapy was carried out using a computerized scanner emitting He-Ne(C W) with a wavelength of 632.8 nm and the fluence was 5 j/cm 2 . Experimental investigation have been carried out along two main lines: Biochemical investigations for the assessment of serum transferases and histopathological assessment of liver and skin biopsy.On the basis of the current results it could be concluded that mice exposed to whole body gamma irradiation either by the US of the shot or the fractionated sublethal dose suffered an aggravated histopathological changes in the skin and liver tissues which were associated with certain biochemical disturbances of the liver function testes. These undesirable alterations were ameliorated by the early treatment of mice by He -Ne laser immediately post exposure before being irreversibly damaged

  3. Wavelength influence on nitrogen insertion into titanium by nanosecond pulsed laser irradiation in air

    Energy Technology Data Exchange (ETDEWEB)

    Torrent, F.; Lavisse, L. [Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université de Bourgogne, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Berger, P. [CEA/DSM/IRAMIS/SIS2M, CEA-Saclay, F-91191 Gif sur Yvette (France); SIS2M, UMR CEA-CNRS 3299, CEA-Saclay, F-91191 Gif sur Yvette (France); Jouvard, J.-M.; Andrzejewski, H.; Pillon, G.; Bourgeois, S.; Marco de Lucas, M.C. [Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université de Bourgogne, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France)

    2013-08-01

    We studied in this work the influence of the wavelength (532 vs. 1064 nm) on the insertion of nitrogen in titanium targets by surface laser treatments in air. The laser pulses were of 5 ns and the irradiance was lower than 25 × 10{sup 12} W/m{sup 2}. Results obtained using a frequency-doubled Nd:YAG laser at 532 nm were compared with those previously reported for laser treatments at 1064 nm. Nuclear reaction analysis and micro-Raman spectroscopy were used for determining the composition and the structure of the surface layers, respectively. Results showed the lower efficiency of irradiation at 532 nm for nitrogen insertion, which is possible only above threshold conditions depending on both the laser irradiance and the number of cumulated impacts per point. This was explained as being due to a higher ablative effect in the visible range. The insertion of oxygen giving rise to the growth of titanium oxynitrides was also discussed.

  4. Low-level Radioactive waste Management

    International Nuclear Information System (INIS)

    1991-01-01

    This meeting describes low-level radioactive waste management problems and contains 8 papers: 1 Low-level radioactive waste management: exemption concept and criteria used by international organizations. 2 Low-level radioactive waste management: french and foreign regulations 3 Low-level radioactive waste management in EDF nuclear power plants (FRANCE) 4 Low-level radioactive waste management in COGEMA (FRANCE) 5 Importance of low-level radioactive wastes in dismantling strategy in CEA (FRANCE) 6 Low-level radioactive waste management in hospitals 7 Low-level radioactive waste disposal: radiation protection laws 8 Methods of low-level radioactive materials measurements during reactor dismantling or nuclear facilities demolition (FRANCE)

  5. Comparison of therapeutic effects between pulsed and continuous wave 810-nm wavelength laser irradiation for traumatic brain injury in mice.

    Directory of Open Access Journals (Sweden)

    Takahiro Ando

    Full Text Available Transcranial low-level laser therapy (LLLT using near-infrared light can efficiently penetrate through the scalp and skull and could allow non-invasive treatment for traumatic brain injury (TBI. In the present study, we compared the therapeutic effect using 810-nm wavelength laser light in continuous and pulsed wave modes in a mouse model of TBI.TBI was induced by a controlled cortical-impact device and 4-hours post-TBI 1-group received a sham treatment and 3-groups received a single exposure to transcranial LLLT, either continuous wave or pulsed at 10-Hz or 100-Hz with a 50% duty cycle. An 810-nm Ga-Al-As diode laser delivered a spot with diameter of 1-cm onto the injured head with a power density of 50-mW/cm(2 for 12-minutes giving a fluence of 36-J/cm(2. Neurological severity score (NSS and body weight were measured up to 4 weeks. Mice were sacrificed at 2, 15 and 28 days post-TBI and the lesion size was histologically analyzed. The quantity of ATP production in the brain tissue was determined immediately after laser irradiation. We examined the role of LLLT on the psychological state of the mice at 1 day and 4 weeks after TBI using tail suspension test and forced swim test.The 810-nm laser pulsed at 10-Hz was the most effective judged by improvement in NSS and body weight although the other laser regimens were also effective. The brain lesion volume of mice treated with 10-Hz pulsed-laser irradiation was significantly lower than control group at 15-days and 4-weeks post-TBI. Moreover, we found an antidepressant effect of LLLT at 4-weeks as shown by forced swim and tail suspension tests.The therapeutic effect of LLLT for TBI with an 810-nm laser was more effective at 10-Hz pulse frequency than at CW and 100-Hz. This finding may provide a new insight into biological mechanisms of LLLT.

  6. Low level radioactive waste disposal

    International Nuclear Information System (INIS)

    Balaz, J.; Chren, O.

    2015-01-01

    The Mochovce National Radwaste Repository is a near surface multi-barrier disposal facility for disposal of processed low and very low level radioactive wastes (radwastes) resulting from the operation and decommissioning of nuclear facilities situated in the territory of the Slovak Republic and from research institutes, laboratories, hospitals and other institutions (institutional RAW) which are in compliance with the acceptance criteria. The basic safety requirement of the Repository is to avoid a radioactive release to the environment during its operation and institutional inspection. This commitment is covered by the protection barrier system. The method of solution designed and implemented at the Repository construction complies with the latest knowledge and practice of the repository developments all over the world and meets requirements for the safe radwaste disposal with minimum environmental consequences. All wastes are solidified and have to meet the acceptance criteria before disposal into the Repository. They are processed and treated at the Bohunice RAW Treatment Centre and Liquid RAW Final Treatment Facility at Mochovce. The disposal facility for low level radwastes consists of two double-rows of reinforced concrete vaults with total capacity 7 200 fibre reinforced concrete containers (FCCs) with RAW. One double-row contains 40 The operation of the Repository was started in year 2001 and after ten years, in 2011 was conducted the periodic assessment of nuclear safety with positive results. Till the end of year 2014 was disposed to the Repository 11 514 m 3 RAW. The analysis of total RAW production from operation and decommissioning of all nuclear installation in SR, which has been carried out in frame of the BIDSF project C9.1, has showed that the total volume estimation of conditioned waste is 108 thousand m 3 of which 45.5 % are low level waste (LLW) and 54,5 % very low level waste (VLLW). On the base of this fact there is the need to build 7

  7. Tradescantia in studies of genetic effects of low level radiation

    International Nuclear Information System (INIS)

    Yamashita, Atsushi

    1976-01-01

    Tradescantia in studies on genetic effects of low level radiation is briefly introduced. Radiosensitivity, method of screening stamen hair mutation, materials in current uses, spontaneous mutation rate, and modifying factors are refered. For stamen hair mutation b values in exponential model were lower in irradiation with low dose rate at high environmental temperature. The dose response curves under these modifying conditions, when extrapolated to low dose range, well fit to the line which was obtained by Sparrow's experiment of low level irradiation. In chronic irradiation, the frequency of stamen hair mutation reaches to the constant value after 17 days from the start of irradiation, and is as much as 4 times higher than the peak value in one day irradiation at the same exposure rate. The spontaneous mutation rate of KU-7 varied with temperature. The increase with 1 0 C increment of mean temperature was -0.04%. Uses of Tradescantia in monitoring the environmental radiation is discussed. (auth.)

  8. TENS and low-level laser therapy in the management of temporomandibular disorders Aplicação de TENS e laser de baixa freqüência no tratamento das disfunções temporomandibulares

    Directory of Open Access Journals (Sweden)

    Melissa Thiemi Kato

    2006-04-01

    Full Text Available Pain relief and reestablishment of normal jaw function are the main goals of conservative management of Temporomandibular Disorders (TMD. Transcutaneous electrical nerve stimulation (TENS and laser therapy are part of these modalities, although little is known about their real efficacy in controlled studies. This research compared these two treatments in a sample of 18 patients with chronic TMD of muscular origin, divided into two groups (LASER and TENS. Treatment consisted of ten sessions, in a period of 30 days. Active range of motion (AROM, visual analogue scale (VAS of pain and muscle (masseter and anterior temporalis palpation were used for follow-up analysis. Data were analyzed by Friedman test and ANOVA for repeated measurements. Results showed decrease in pain and increase in AROM for both groups (pO tratamento das Disfunções Temporomandibulares (DTM objetiva ser conservador e reversível para alívio da dor e restauração da função normal. Sendo assim, tratamentos como a estimulação neural elétrica transcutânea (TENS e o laser de baixa freqüência têm sido utilizados. Portanto, foi premissa deste trabalho a comparação do TENS com o a terapia com laser de baixa freqüência no tratamento de pacientes com DTM. Foram selecionados dezoito pacientes com sinais e sintomas de DTM crônica de origem muscular. O grupo LASER recebeu aplicação de laser e o grupo TENS, estimulação elétrica, totalizando 10 sessões, três vezes por semana, durante um mês. A avaliação foi feita imediatamente antes e 5 minutos após cada sessão terapêutica, por meio da escala de análise visual (EAV para o registro da sensação de dor mensuração de abertura máxima e palpação muscular ( masseter e temporal anterior. Para análise estatística foram utilizados o teste de Friedman e ANOVA para mensurações repetidas. Os resultados demonstraram decréscimo na EAV e aumento da abertura bucal máxima de ambos os grupos (p<0,05. A palpa

  9. Characterization of laser ablation of copper in the irradiance regime of laser-induced breakdown spectroscopy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Picard, J., E-mail: jessica.picard@cea.fr [Commissariat à l' Energie Atomique, DAM, Valduc, F-21120 Is-sur-Tille (France); Sirven, J.-B.; Lacour, J.-L. [Commissariat à l' Energie Atomique, DEN/DANS/DPC/SEARS/LANIE, Saclay, F-91191 Gif-sur-Yvette (France); Musset, O. [Université de Bourgogne, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR CNRS 5209, F-21000 Dijon (France); Cardona, D.; Hubinois, J.-C. [Commissariat à l' Energie Atomique, DAM, Valduc, F-21120 Is-sur-Tille (France); Mauchien, P. [Commissariat à l' Energie Atomique, DEN/DANS/DPC/SEARS/LANIE, Saclay, F-91191 Gif-sur-Yvette (France)

    2014-11-01

    The LIBS signal depends both on the ablated mass and on the plasma excitation temperature. These fundamental parameters depend in a complex manner on laser ablation and on laser–plasma coupling. As several works in the literature suggest that laser ablation processes play a predominant role compared to plasma heating phenomena in the LIBS signal variations, this paper focuses on the study of laser ablation. The objective was to determine an interaction regime enabling to maximally control the laser ablation. Nanosecond laser ablation of copper at 266 nm was characterized by scanning electron microscopy and optical profilometry analysis, in air at 1 bar and in the vacuum. The laser beam spatial profile at the sample surface was characterized in order to give realistic values of the irradiance. The effect of the number of accumulated laser shots on the crater volume was studied. Then, the ablation crater morphology, volume, depth and diameter were measured as a function of irradiance between 0.35 and 96 GW/cm². Results show that in the vacuum, a regular trend is observed over the whole irradiance range. In air at 1 bar, below a certain irradiance, laser ablation is very similar to the vacuum case, and the ablation efficiency of copper was estimated at 0.15 ± 0.03 atom/photon. Beyond this irradiance, the laser beam propagation is strongly disrupted by the expansion of the dense plasma, and plasma shielding appears. The fraction of laser energy used for laser ablation and for plasma heating is estimated in the different irradiance regimes. - Highlights: • The morphology of copper's craters was studied as a function of the pulse energy. • Correlation at low energy and two pressures between crater volume and pulse energy • The ablation efficiency of copper at 1 bar is equal to 0.15 atom/photon. • Ablation efficiency in the vacuum is not limited by laser–plasma interaction. • Physical mechanisms of laser ablation at both pressures are discussed.

  10. Risks of low-level radiation - the evidence of epidemiology

    International Nuclear Information System (INIS)

    Gloag, D.

    1980-01-01

    The difficulties involved in estimating risks from very low levels of radiation and the use of dose-response models for cancer incidence are discussed with reference to the third BEIR Committee report on the Effects on Populations of Exposure to low levels of Ionizing Radiation (1980). Cancer risk estimates derived from different epidemiological studies are reviewed. They include atom bomb survivors, medically irradiated groups and occupational groups. (36 references). (author)

  11. Low-Level Laser and Light-Emitting Diode Therapy for Pain Control in Hyperglycemic and Normoglycemic Patients Who Underwent Coronary Bypass Surgery with Internal Mammary Artery Grafts: A Randomized, Double-Blind Study with Follow-Up.

    Science.gov (United States)

    Lima, Andréa Conceição Gomes; Fernandes, Gilderlene Alves; Gonzaga, Isabel Clarisse; de Barros Araújo, Raimundo; de Oliveira, Rauirys Alencar; Nicolau, Renata Amadei

    2016-06-01

    This study aimed to evaluate the efficacy of low-level laser therapy (LLLT) and light-emitting diodes (LEDs) for reducing pain in hyperglycemic and normoglycemic patients who underwent coronary artery bypass surgery with internal mammary artery grafts. This study was conducted on 120 volunteers who underwent elective coronary artery bypass graft (CABG) surgery. The volunteers were randomly allocated to four different groups of equal size (n = 30): control, placebo, LLLT [λ = 640 nm and spatial average energy fluence (SAEF) = 1.06 J/cm(2)], and LED (λ = 660 ± 20 nm and SAEF = 0.24 J/cm(2)). Participants were also divided into hyperglycemic and normoglycemic subgroups, according to their fasting blood glucose test result before surgery. The outcome assessed was pain during coughing by a visual analog scale (VAS) and the McGill Pain Questionnaire. The patients were followed for 1 month after the surgery. The LLLT and LED groups showed a greater decrease in pain, with similar results, as indicated by both the VAS and the McGill questionnaire (p ≤ 0.05), on the 6th and 8th postoperative day compared with the placebo and control groups. The outcomes were also similar between hyperglycemic and normoglycemic patients. One month after the surgery, almost no individual reported pain during coughing. LLLT and LED had similar analgesic effects in hyperglycemic and normoglycemic patients, better than placebo and control groups.

  12. What is the best treatment to decrease pro-inflammatory cytokine release in acute skeletal muscle injury induced by trauma in rats: low-level laser therapy, diclofenac, or cryotherapy?

    Science.gov (United States)

    de Almeida, Patrícia; Tomazoni, Shaiane Silva; Frigo, Lucio; de Carvalho, Paulo de Tarso Camillo; Vanin, Adriane Aver; Santos, Larissa Aline; Albuquerque-Pontes, Gianna Móes; De Marchi, Thiago; Tairova, Olga; Marcos, Rodrigo Labat; Lopes-Martins, Rodrigo Álvaro Brandão; Leal-Junior, Ernesto Cesar Pinto

    2014-03-01

    Currently, treatment of muscle injuries represents a challenge in clinical practice. In acute phase, the most employed therapies are cryotherapy and nonsteroidal anti-inflammatory drugs. In the last years, low-level laser therapy (LLLT) has becoming a promising therapeutic agent; however, its effects are not fully known. The aim of this study was to analyze the effects of sodium diclofenac (topical application), cryotherapy, and LLLT on pro-inflammatory cytokine levels after a controlled model of muscle injury. For such, we performed a single trauma in tibialis anterior muscle of rats. After 1 h, animals were treated with sodium diclofenac (11.6 mg/g of solution), cryotherapy (20 min), or LLLT (904 nm; superpulsed; 700 Hz; 60 mW mean output power; 1.67 W/cm(2); 1, 3, 6 or 9 J; 17, 50, 100 or 150 s). Assessment of interleukin-1β and interleukin-6 (IL-1β and IL-6) and tumor necrosis factor-alpha (TNF-α) levels was performed at 6 h after trauma employing enzyme-linked immunosorbent assay method. LLLT with 1 J dose significantly decreased (p cryotherapy groups. On the other hand, treatment with diclofenac and cryotherapy does not decrease pro-inflammatory cytokine levels compared to the non-treated injured group. Therefore, we can conclude that 904 nm LLLT with 1 J dose has better effects than topical application of diclofenac or cryotherapy in acute inflammatory phase after muscle trauma.

  13. Low level radiation: biological effects

    International Nuclear Information System (INIS)

    Loken, M.K.

    1983-01-01

    It is imperative that physicians and scientists using radiations in health care delivery continue to assess the benefits derived, vs. potential risk, to patients and radiation workers being exposed to radiation in its various forms as part of our health delivery system. Insofar as possible we should assure our patients and ourselves that the benefits outweigh the potential hazards involved. Inferences as to the possible biological effects of low level radiation are generally based on extrapolations from those effects observed and measured following acute exposures to considerably higher doses of radiation. Thus, in order to shed light on the question of the possible biological effects of low level radiation, a