Photobiomodulation (PBM) therapy involves the irradiation of tissues with red to near- infrared (NIR) light at low power densities to stimulate healing, reduce inflammation, and promote optimal cellular functioning. These beneficial effects are thought to occur due to the absorption of NIR light by the chromophore, and terminal enzyme in the mitochondrial electron transport chain, cytochrome c oxidase (CCO). It is hypothesized that increased oxygen consumption due to the photostimulation of CCO, as well as photodissociation of the vasodilator nitric oxide from its binding site in the binuclear center of CCO, contribute to improved tissue healing by increasing blood flow to the irradiated region. Applied to the brain, PBM therapy has the potential to improve many neurological injuries and diseases for which reduced cerebral blood flow (CBF) is a common finding. This study examines whether cortical irradiation with NIR light has an impact on CBF in mice. Mice were administered brain PBM via 810nm, 190mW LED for 18 minutes. CBF was measured before, during, and after treatment using Doppler Optical Coherence Tomography. Results from 16 trials demonstrated a significant, 40% increase in CBF during NIR treatment. This CBF increase was not observed during control trials. Additionally, irradiation with a 730nm LED did not increase CBF, indicating that the blood flow increase observed with 810nm irradiation was not simply due to tissue heating. These findings provide support for the value of PBM therapy for the treatment of neurological conditions. / 2023-05-14T00:00:00Z

Master of Science / Department of Architectural Engineering and Construction Science / Fred Hasler / Over 26.6 million people suffer from Alzheimer's Disease in the United States, and while no cure exists, how their built environment is illuminated - lamp type, color selection, wavelengths emitted, luminaire specifications, and luminaire layout - may enhance the lives of Alzheimer's patients (APs), their relatives, and caretakers. Research has found mixed results when it comes to selecting the correct lamp, but most researchers agree illumination levels benefit APs quality of life. Achieving higher illumination levels can be achieved by adding more luminaires to the ambient lighting layout, placing additional task lighting in specific locations, or using light therapy. Exposing APs to higher illumination levels can have positive behavioral benefits and help shift the circadian rhythm. Common problems such as aggression, sleepiness, and agitation can be reduced if proper lighting layouts or light therapy is used on a consistent basis. Adding to research, several Alzheimer’s facilities in Kansas and Colorado were contacted to complete questionnaires about their lighting and resident’s behaviors. Upon analysis, these facilities concurred with research about lamp types, daylight, and luminaire layouts showing higher levels of illumination were preferred by APs and also where they displayed their best behaviors. Ninety percent of facilities agreed that APs enjoyed sitting by the windows, and over half agreed APs exhibited better behavior while seated here. Homes with CLFs documented APs were typically more calm and happy than those with tubular fluorescents, but the conclusions made need additional research to support the findings.

Light not only allows us to see but is also fundamental to our health and well-being. Several parameters of light exposure, such as wavelengths, intensity, and timing of exposure, all play an important role on its effects on psychophysiological functions. The way in which studies have previously quantified light (based on intensity), has been found to be inadequate since it does not consider the spectrum of light which influences non-visual effects. Among these non-visual effects, light has been found to have antidepressant effects, however, these effects remain inconsistent for non-seasonal depression and their underlying mechanisms remain elusive. The three research studies in this thesis investigated the effects of light on mood. The first study focused on the direct pathway between light and mood, aiming to predict mood outcomes based on the amount of intrinsically photosensitive retinal ganglion cells (ipRGC) stimulation from polychromatic light in healthy individuals. The second and third studies focused on the indirect pathways, exploring predictors and underlying mechanisms of mood improvements by means of sleep and circadian re-alignment in the context of non-seasonal depression. These studies explored the antidepressant mechanisms of monochromatic light therapy and predictive models of mood improvement. The results from study I (systematic review) suggest that ipRGCs may not be as involved in the mood improvement associated with polychromatic light. Drawing strong conclusions from these results are, however, cautioned. Mood metrics used across the studies were inconsistent and the light sources were not designed to maximally stimulate ipRGCs. The results from study II (open-label trial) support the notion that light therapy does have antidepressant effects in people with non-seasonal depression. The underlying mechanisms for these antidepressant effects may involve improvements in sleep initiation and daytime functioning. Individuals with difficulties with fallings asleep and waking-up may be those that respond most prominently to light therapy. The results from study III (randomized controlled trial) indicate that depression symptoms improved slightly more in the active light therapy condition as opposed to a placebo condition. Although this effect was modest across the overall group, there were considerable inter-individual variations in treatment response. The degree of improvement in mood was associated with improvement in pre-sleep thoughts and the circadian rhythmicity of skin temperature. Short REM latency and worst global subjective sleep were predictive of greater response to light therapy. Overall, further research is required to disentangle the involvement of the different photoreceptors in the mood response to polychromatic light in healthy individuals. Monochromatic light therapy for non-seasonal depression yields overall modest antidepressant effects. Clinical applications of light therapy may benefit from further research investigating differential effects in sub-groups of depression and underlying mechanisms in larger studies.

Delayed sleep phase disorder (DSPD) is the most common circadian rhythm sleep disorder. Persons with DSPD have great difficulties falling asleep and waking up at conventional times. To diagnose DSPD this delayed sleep-wake rhythm should cause social impairment and distress for the individual. Evening melatonin and morning bright light are the recommended treatments. The overall aim of this thesis was to evaluate at-home treatment with Light therapy (LT) and the feasibility of adding cognitive behavior therapy (CBT) to LT in DSPD, furthermore prevalence, diagnostic aspects and associated factors were investigated. Study I included 673 randomly selected individuals aged 16–26 years. The prevalence of DSPD was 4.0%. Unemployment (defined as an absence of educational or work activities) and an elevated level of anxiety were associated with DSPD. In study II, dim light melatonin onset (DLMO) was measured in healthy adults. Time for DLMO DLMO (Mean±SD) was 20:58±55 minutes. Studies III, IV, and V present results from a randomized controlled trial examining the feasibility of CBT as an additive treatment to LT with scheduled rise times, in persons with DSPD. Sleep onset and sleep offset was significantly advanced from baseline (03:00±1:20; 10:22±2:02 respectively) to the end of LT (01:27±1:41; 08:05±1:29, p<0.001 respectively). This advancement was predicted by consistent daily usage of the LT-lamp. At the follow-ups after LT and CBT or LT alone, sleep onset remained stable, sleep offset was delayed, and sleep difficulties were further improved, but there was no significant group interaction over time. There was a significant group interaction over time in the severity of anxiety and depressive symptoms, both in favor of the LT+CBT group. Conclusively, DSPD was common among adolescents and young adults and it was associated with unemployment and elevated levels of anxiety. DLMO appeared in the expected time range in healthy working adults. At-home treatment with LT with scheduled rise times advanced sleep-wake rhythm and improved sleep difficulties in DSPD. Even though sleep-wake rhythm was not further advanced or better preserved in the participants that received LT+CBT compared to LT alone, the addition of CBT to the treatment regimen was feasible and well accepted.

A fotobioestimulação por laser e LED é uma tendência terapêutica inovadora e não invasiva. Os efeitos fotofísicos e fotoquímicos dessa terapia geram imunomodulação, aceleram a cicatrização e angiogênese, bem como reduzem a dor. Dessa forma tem se buscado o emprego desses estímulos no tecido ósseo, porém ainda inexistem padrões definidos para obter a melhor fotobioestimulação nas células ósseas. O objetivo desse trabalho foi avaliar a capacidade da fotobioestimulação na viabilidade celular e mineralização de células da granulação óssea de ratos (rGO). Células rGO na 6ª passagem foram plaqueadas em placas de 96 poços para os ensaios de viabilidade celular (1x10³) e em placas de 24 poços para os ensaios de cicatrização de feridas in vitro (1x104), mineralização e atividade da fosfatase alcalina (FALC) (4x104). As células receberam DMEM (10% SFB) e irradiações com laser (AlGaAs- 660nm e AlGaInP-810nm) e LED (637±15nm). Os grupos experimentais foram: laser vermelho (3 e 5 J/cm²), laser infravermelho (3 e 5 J/cm²) e LED (3 e 5s), além dos grupos controles, positivo (C+) e negativo (C-, 1%SFB). Para os ensaios de mineralização e atividade de fosfatase alcalina, além do meio convencional, grupos com meio osteogênico e os mesmos tratamentos luminosos foram acrescentados. A viabilidade celular foi avaliada pelos testes do MTT e cristal violeta nos períodos de 24, 48, 72 e 96h. O ensaio de cicatrização de feridas in vitro foi avaliado por meio da porcentagem da área de fechamento da ferida nos períodos de 12, 24, 36, 48h. O teste de mineralização foi feito por meio do teste com vermelho de alizarina nos períodos de 14, 21 e 28 dias enquanto que a atividade da FALC foi medida em 7, 14 e 21 dias. A análise estatística foi realizada através dos testes ANOVA complementados por Tukey (p<0,05). Os resultados mostraram que as terapias com luz de maneira geral aumentaram a viabilidade o fechamento da ferida in vitro, principalmente os grupos laser vermelho e LED5s (p<0,05). Pode-se observar um bom desempenho do grupo LED5s no ensaio de mineralização, onde nos grupos que receberam meio osteogênico houve um efeito somatório com a ação da fotobioestimulação promovendo maior produção de nódulos in vitro. Também, as terapias com luz, estimularam a produção de nódulos mineralizados nos grupos que receberam meio convencional de forma a superar o C+ osteogênico (p<0,05), denotando uma ação de indução osteogênica a partir da fotobioestimulação. A fosfatase alcalina foi estimulada pelos tratamentos com luz no período de 7 dias (p<0,05). Em conclusão, as terapias com laser e LED foram capazes de estimular a viabilidade e migração celular e eventos de mineralização em osteoblastos, sendo que o laser vermelho e LED promoveram os melhores resultados. / Photobiomodulation by laser and LED is a new therapeutic non-invasive trend. Photophysical and photochemical effects occur in immunomodulation, acceleration of wound healing and angiogenesis and reduction of pain. These effects are desired in bone tissue but there are no defined parameters for light irradiation and no consensus for the best effect on osseous cells. The aim of this study was to evaluate photobiomodulation effects on cell viability and mineralization events of rat osseous granulation cells (rGO). Cells in 6th passage were plated in 96-well plates for viability tests (1x10³ cells), and 24-well plates for in vitro wound healing test (1x104 cells), mineralization and alkaline phosphatases (AF) activity (4x104 cells). Cells were cultured in DMEM (10% bovine fetal serum) and irradiation with lasers (AlGaAs-660nm e AlGaInP-810nm) and LED (637±15nm). Experimental groups were red laser (3 and 5 J/cm²), infrared laser (3 and 5 J/cm²), LED (3 and 5s), positive(C+) and negative controls (C-, 1% bovine fetal serum). For mineralization and AF assays, other groups with osteogenic medium and same light treatments were added. Cell viability was evaluated by MTT and crystal violet tests at 24, 48, 72 and 96h. In vitro wound healing test evaluated the percentage of wound closure area by cells migration at 12, 24, 36, 48h. Mineralization test was done by alizarin red at 14, 21 and 28 days. AF activity was measured at 7, 14 and 21 days. Statistical analysis was performed by ANOVA complemented by Tukeys test (p<0,05). Results showed that light therapies in general increased viability and wound healing closure, mostly red laser and LED5s (p<0,05). Best results in mineralization stimulation were observed for LED5s. In groups with osteogenic medium, a synergistic effect of photobiomodulation resulted in higher numbers of mineral nodules. Light groups stimulated higher mineral nodule formation than positive control (p>0.05) even in groups with regular medium, showing an osteogenic induction by light. Increased AF activity was observed at 7 days in light treatment groups (p<0,05). In conclusion, laser and LED photobiostimulation increased viability, cell migration and mineralization events in osteoblasts with best results for red laser and LED.

A Terapia com Laser de Baixa Intensidade (TLBI) pode ser utilizada para tratar dores agudas e crônicas. Entender as vias da dor e as interações de fótons com tecidos neurais possibilitará compreender melhor essas terapias. A nocicepção pode ser autocontrolada por analgésicos endógenos, opióides naturais que bloqueiam a liberação de neurotransmissores excitatórios e, portanto, fazem uma inibição sensorial total e inespecífica. Sabe-se que a TLBI pode estimular a liberação desses analgésicos endógenos e inibir temporariamente o transporte axonal em fibras de pequeno diâmetro. Conhecer a fluência luminosa no interior do tecido neural é essencial para avaliar as hipóteses descritas, no entanto, devido à complexidade dos tecidos biológicos, calcular (ou simular) as interações da luz com os tecidos é impraticável. Para superar esse problema, desenvolvemos experimentos para estimar a fluência de luz em aplicação transcraniana de laser e mapeamos as propriedades ópticas do encéfalo de rato. Foi possível diferenciar tecidos encefálicos por suas características de atenuação da intensidade luminosa e estimar a profundidade da penetração da luz que pode ser de mais de 20 mm. Encontramos redução da dor evocada por pressão, calor, frio ou inflamação após TLBI transcraniana em camundongos. Para esse estudo comportamental, desenvolvemos um equipamento para avaliar o limiar de dor por aplicação de pressão nos animais, que opera com melhor precisão que os instrumentos comerciais. Os mecanismos de fotoneuromodulação foram investigados por quantificação de Trifosfato de Adenosina (ATP), imunofluorescência e marcação com hematoxilina-eosina de tecidos encefálicos que foram visualizados por microscópio confocal. A iluminação transcraniana aumentou a produção de ATP e de Fosfatase ácida prostática (um analgésico endógeno) e reduziu a quantidade do neurotransmissor glutamato, responsável pela condução da informação nociceptiva. Por outro lado, não observamos alteração na concentração de tubulina, um dos constituintes do citoesqueleto, e a marcação com hematoxilina-eosina revelou que não houve dano ao tecido decorrente da iluminação. Os achados apresentados nesse estudo atestam a relevância e eficácia da fotoneuromodulação proveniente de iluminação transcraniana com laser de 808 nm para suprimir a nocicepção em camundongos. Esse estudo é pioneiro na elucidação dos mecanismos de ação da fotoneuromodulação da dor in vivo. / Low-level Light therapy (LLLT) can treat acute and chronic pain. Getting knowledge about the pain pathways and the photon-neuron interactions may contribute to a better understanding of this therapy. The nociception may be self-controlled by endogenous analgesics, natural opioids that block the release of excitatory neurotransmitters, and thus make a total and nonspecific sensory inhibition. It is known that LLLT can stimulate the release of these endogenous analgesics, so it temporarily inhibits axonal transport in small diameter fibers. The knowledge of light fluence through neural tissue is essential to test the discussed assumptions. However, due to the complexity of biological tissues, the calculation (or simulation) of light-tissue interactions is impractical. In order to overcome this problem, we developed an experimental setup to estimate the light fluence in a transcranial LLLT and to map the optical properties of rat brains. It was possible to differentiate cerebral tissues and to estimate the depth of light penetration, which is more than 20 mm. We found a decrease in pain evoked either by pressure, heat, cold or inflammation after transcranial LLLT in mice. For this animal behavioral study, we developed an equipment to assess the pain threshold with pressure stimulus, which operates with better precision than commercial instruments. The LLLT mechanisms were investigated by Adenosine triphosphate ATP quantification, immunofluorescence and haematoxylin and eosin staining of brain tissues which were imaged by confocal microscopy. The transcranial irradiation increased ATP and prostatic acid phosphatase (an endogenous analgesic) production and reduced the amount of glutamate, the neurotransmitter responsible for conducting nociceptive information. There was no change in the concentration of tubulin, a constituent of the cytoskeleton, and the haematoxylin and eosin staining revealed no tissue damage due to the irradiation. This study is pioneer in elucidating the mechanisms of in vivo photoneuromodulation of pain.

Orientador: Maeli Dal Pai / Coorientador: Francis Lopes Pacagnelli / Banca: Adriana Pertile / Banca: Thiago Luiz de Russo / Banca: Selma Maria Michelin Matheus / Banca: Ines Cristina Giometti / Resumo: Pesquisas recentes na área de fisioterapia buscam elucidar as alterações envolvidas na regeneração do músculo esquelético após a aplicação de recursos terapêuticos. Neste contexto, a aplicação da Laserterapia de Baixa Intensidade tem se mostrado eficaz para melhorar o processo de regeneração muscular, entretanto, o tipo de laser, os parâmetros de radiação, período avaliado e os mecanismos moleculares envolvidos no processo de regeneração demonstram resultados discrepantes. O objetivo deste estudo foi avaliar o efeito da Laserterapia de Baixa Intensidade, tipo (AsGa), comprimento de onda de 904 nm, 7 dias após a lesão e verificar se o tipo de laser e a dose escolhida tem influência no processo de regeneração muscular. Foram utilizados nesse estudo trinta ratos Wistar, machos, adultos (três meses de idade), peso corporal médio de 210-340g. Os animais foram randomizados em três grupos: Grupo Controle (C, n= 10), Grupo lesado não tratado (L, n=10) e o Grupo lesado e tratado (LT, n= 10). Após anestesia dos animias, a lesão muscular foi induzida por congelamento (criolesão) na região central do ventre do músculo tibial anterior (TA) de ambos os membros posteriores, por meio de uma haste de ferro previamente imersa em nitrogênio líquido. Como recurso terapêutico foi utilizado o laser de AsGa, comprimento de onda de 904 nanômetros. As aplicações do laser foram iniciadas 24 horas após a lesão, diariamente, com densidade de energia de 69 J/cm², (48 segundos), durante cinco dias, em dois pontos na área da lesão. Aos 7 dias, os animais foram pesados e mortos; o músculo TA de ambos membros posteriores foi retirado e processado para as análises morfológica e molecular. O músculo TA esquerdo foi congelado em nitrogênio líquido e cortes histológicos obtidos em criostato foram submetidos às coloraçõe s Hematoxilina e Eosina (para análise morfológica) e Picrosirius (para análise do colágeno). O músculo TA... / Abstract: Recent research in the field of physiotherapy has aimed to elucidate the main changes involved in skeletal muscle regeneration after application of therapeutic resources. In this context, the application of Low Level Laser Therapy has proven to be effective at improving the muscle regeneration process. However, the type of laser, irradiation parameters, evaluation period and molecular mechanisms involved in the regeneration process present conflicting results. The aim of this study was to evaluate the effects of Low Level Laser Therapy, type GaAs at 904 nm, during the muscle regeneration process, for seven days after the lesion, and verify whether both the GaAs laser and chosen dose influence the muscle regeneration process. Thirty Wistar male adult rats (three-month old), mean body weight 210 - 340 g were used in this study. The animals were randomized into three groups: Control Group (C, n=10), Untreated Lesion Group (L, n=10) and Treated Lesion group (TL, n=10). After anesthetizing the animals, muscle lesion was induced by freezing (cryoinjury) in the middle belly portion of the tibialis anterior muscle (TA) of both hind limbs, using an iron rod previously immersed in liquid nitrogen. A GaAs laser, with a wavelength of 904 nm was used as a therapeutic resource. Daily laser applications were initiated 24 hours after lesion, with an energy density of 69 J/cm2, (48 seconds), for five consecutive days, at two points in the lesion area. On the seventh day, the animals were euthanized and weighed; the TA muscles from both hindlimbs were removed and processed for morphological and molecular analysis. The left TA muscle was frozen in liquid nitrogen and histological sections obtained in a cryostat were submitted to Hematoxylin and Eosin (for morphological analysis) and Picrosirius (for collagen analysis) staining. The right TA muscle was used for the analysis of gene expression of MyoD, myogenin, TNF-α and TGF-β by using the Polymerase... / Doutor

A fotobioestimulação por laser e LED é uma tendência terapêutica inovadora e não invasiva. Os efeitos fotofísicos e fotoquímicos dessa terapia geram imunomodulação, aceleram a cicatrização e angiogênese, bem como reduzem a dor. Dessa forma tem se buscado o emprego desses estímulos no tecido ósseo, porém ainda inexistem padrões definidos para obter a melhor fotobioestimulação nas células ósseas. O objetivo desse trabalho foi avaliar a capacidade da fotobioestimulação na viabilidade celular e mineralização de células da granulação óssea de ratos (rGO). Células rGO na 6ª passagem foram plaqueadas em placas de 96 poços para os ensaios de viabilidade celular (1x10³) e em placas de 24 poços para os ensaios de cicatrização de feridas in vitro (1x104), mineralização e atividade da fosfatase alcalina (FALC) (4x104). As células receberam DMEM (10% SFB) e irradiações com laser (AlGaAs- 660nm e AlGaInP-810nm) e LED (637±15nm). Os grupos experimentais foram: laser vermelho (3 e 5 J/cm²), laser infravermelho (3 e 5 J/cm²) e LED (3 e 5s), além dos grupos controles, positivo (C+) e negativo (C-, 1%SFB). Para os ensaios de mineralização e atividade de fosfatase alcalina, além do meio convencional, grupos com meio osteogênico e os mesmos tratamentos luminosos foram acrescentados. A viabilidade celular foi avaliada pelos testes do MTT e cristal violeta nos períodos de 24, 48, 72 e 96h. O ensaio de cicatrização de feridas in vitro foi avaliado por meio da porcentagem da área de fechamento da ferida nos períodos de 12, 24, 36, 48h. O teste de mineralização foi feito por meio do teste com vermelho de alizarina nos períodos de 14, 21 e 28 dias enquanto que a atividade da FALC foi medida em 7, 14 e 21 dias. A análise estatística foi realizada através dos testes ANOVA complementados por Tukey (p<0,05). Os resultados mostraram que as terapias com luz de maneira geral aumentaram a viabilidade o fechamento da ferida in vitro, principalmente os grupos laser vermelho e LED5s (p<0,05). Pode-se observar um bom desempenho do grupo LED5s no ensaio de mineralização, onde nos grupos que receberam meio osteogênico houve um efeito somatório com a ação da fotobioestimulação promovendo maior produção de nódulos in vitro. Também, as terapias com luz, estimularam a produção de nódulos mineralizados nos grupos que receberam meio convencional de forma a superar o C+ osteogênico (p<0,05), denotando uma ação de indução osteogênica a partir da fotobioestimulação. A fosfatase alcalina foi estimulada pelos tratamentos com luz no período de 7 dias (p<0,05). Em conclusão, as terapias com laser e LED foram capazes de estimular a viabilidade e migração celular e eventos de mineralização em osteoblastos, sendo que o laser vermelho e LED promoveram os melhores resultados. / Photobiomodulation by laser and LED is a new therapeutic non-invasive trend. Photophysical and photochemical effects occur in immunomodulation, acceleration of wound healing and angiogenesis and reduction of pain. These effects are desired in bone tissue but there are no defined parameters for light irradiation and no consensus for the best effect on osseous cells. The aim of this study was to evaluate photobiomodulation effects on cell viability and mineralization events of rat osseous granulation cells (rGO). Cells in 6th passage were plated in 96-well plates for viability tests (1x10³ cells), and 24-well plates for in vitro wound healing test (1x104 cells), mineralization and alkaline phosphatases (AF) activity (4x104 cells). Cells were cultured in DMEM (10% bovine fetal serum) and irradiation with lasers (AlGaAs-660nm e AlGaInP-810nm) and LED (637±15nm). Experimental groups were red laser (3 and 5 J/cm²), infrared laser (3 and 5 J/cm²), LED (3 and 5s), positive(C+) and negative controls (C-, 1% bovine fetal serum). For mineralization and AF assays, other groups with osteogenic medium and same light treatments were added. Cell viability was evaluated by MTT and crystal violet tests at 24, 48, 72 and 96h. In vitro wound healing test evaluated the percentage of wound closure area by cells migration at 12, 24, 36, 48h. Mineralization test was done by alizarin red at 14, 21 and 28 days. AF activity was measured at 7, 14 and 21 days. Statistical analysis was performed by ANOVA complemented by Tukeys test (p<0,05). Results showed that light therapies in general increased viability and wound healing closure, mostly red laser and LED5s (p<0,05). Best results in mineralization stimulation were observed for LED5s. In groups with osteogenic medium, a synergistic effect of photobiomodulation resulted in higher numbers of mineral nodules. Light groups stimulated higher mineral nodule formation than positive control (p>0.05) even in groups with regular medium, showing an osteogenic induction by light. Increased AF activity was observed at 7 days in light treatment groups (p<0,05). In conclusion, laser and LED photobiostimulation increased viability, cell migration and mineralization events in osteoblasts with best results for red laser and LED.

Made available in DSpace on 2016-09-27T13:39:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-13. Added 1 bitstream(s) on 2016-09-27T13:45:05Z : No. of bitstreams: 1 000869167_20170713.pdf: 476409 bytes, checksum: 4dd9c44d7124cd187387462ed2e6e64c (MD5) Bitstreams deleted on 2017-07-24T11:34:10Z: 000869167_20170713.pdf,. Added 1 bitstream(s) on 2017-07-24T11:35:15Z : No. of bitstreams: 1 000869167.pdf: 1094655 bytes, checksum: 4a14c0b49e1fc1aa7c3854aa79958e40 (MD5) / Pesquisas recentes na área de fisioterapia buscam elucidar as alterações envolvidas na regeneração do músculo esquelético após a aplicação de recursos terapêuticos. Neste contexto, a aplicação da Laserterapia de Baixa Intensidade tem se mostrado eficaz para melhorar o processo de regeneração muscular, entretanto, o tipo de laser, os parâmetros de radiação, período avaliado e os mecanismos moleculares envolvidos no processo de regeneração demonstram resultados discrepantes. O objetivo deste estudo foi avaliar o efeito da Laserterapia de Baixa Intensidade, tipo (AsGa), comprimento de onda de 904 nm, 7 dias após a lesão e verificar se o tipo de laser e a dose escolhida tem influência no processo de regeneração muscular. Foram utilizados nesse estudo trinta ratos Wistar, machos, adultos (três meses de idade), peso corporal médio de 210-340g. Os animais foram randomizados em três grupos: Grupo Controle (C, n= 10), Grupo lesado não tratado (L, n=10) e o Grupo lesado e tratado (LT, n= 10). Após anestesia dos animias, a lesão muscular foi induzida por congelamento (criolesão) na região central do ventre do músculo tibial anterior (TA) de ambos os membros posteriores, por meio de uma haste de ferro previamente imersa em nitrogênio líquido. Como recurso terapêutico foi utilizado o laser de AsGa, comprimento de onda de 904 nanômetros. As aplicações do laser foram iniciadas 24 horas após a lesão, diariamente, com densidade de energia de 69 J/cm², (48 segundos), durante cinco dias, em dois pontos na área da lesão. Aos 7 dias, os animais foram pesados e mortos; o músculo TA de ambos membros posteriores foi retirado e processado para as análises morfológica e molecular. O músculo TA esquerdo foi congelado em nitrogênio líquido e cortes histológicos obtidos em criostato foram submetidos às coloraçõe s Hematoxilina e Eosina (para análise morfológica) e Picrosirius (para análise do colágeno). O músculo TA... / Recent research in the field of physiotherapy has aimed to elucidate the main changes involved in skeletal muscle regeneration after application of therapeutic resources. In this context, the application of Low Level Laser Therapy has proven to be effective at improving the muscle regeneration process. However, the type of laser, irradiation parameters, evaluation period and molecular mechanisms involved in the regeneration process present conflicting results. The aim of this study was to evaluate the effects of Low Level Laser Therapy, type GaAs at 904 nm, during the muscle regeneration process, for seven days after the lesion, and verify whether both the GaAs laser and chosen dose influence the muscle regeneration process. Thirty Wistar male adult rats (three-month old), mean body weight 210 - 340 g were used in this study. The animals were randomized into three groups: Control Group (C, n=10), Untreated Lesion Group (L, n=10) and Treated Lesion group (TL, n=10). After anesthetizing the animals, muscle lesion was induced by freezing (cryoinjury) in the middle belly portion of the tibialis anterior muscle (TA) of both hind limbs, using an iron rod previously immersed in liquid nitrogen. A GaAs laser, with a wavelength of 904 nm was used as a therapeutic resource. Daily laser applications were initiated 24 hours after lesion, with an energy density of 69 J/cm2, (48 seconds), for five consecutive days, at two points in the lesion area. On the seventh day, the animals were euthanized and weighed; the TA muscles from both hindlimbs were removed and processed for morphological and molecular analysis. The left TA muscle was frozen in liquid nitrogen and histological sections obtained in a cryostat were submitted to Hematoxylin and Eosin (for morphological analysis) and Picrosirius (for collagen analysis) staining. The right TA muscle was used for the analysis of gene expression of MyoD, myogenin, TNF-α and TGF-β by using the Polymerase...

A Terapia com Laser de Baixa Intensidade (TLBI) pode ser utilizada para tratar dores agudas e crônicas. Entender as vias da dor e as interações de fótons com tecidos neurais possibilitará compreender melhor essas terapias. A nocicepção pode ser autocontrolada por analgésicos endógenos, opióides naturais que bloqueiam a liberação de neurotransmissores excitatórios e, portanto, fazem uma inibição sensorial total e inespecífica. Sabe-se que a TLBI pode estimular a liberação desses analgésicos endógenos e inibir temporariamente o transporte axonal em fibras de pequeno diâmetro. Conhecer a fluência luminosa no interior do tecido neural é essencial para avaliar as hipóteses descritas, no entanto, devido à complexidade dos tecidos biológicos, calcular (ou simular) as interações da luz com os tecidos é impraticável. Para superar esse problema, desenvolvemos experimentos para estimar a fluência de luz em aplicação transcraniana de laser e mapeamos as propriedades ópticas do encéfalo de rato. Foi possível diferenciar tecidos encefálicos por suas características de atenuação da intensidade luminosa e estimar a profundidade da penetração da luz que pode ser de mais de 20 mm. Encontramos redução da dor evocada por pressão, calor, frio ou inflamação após TLBI transcraniana em camundongos. Para esse estudo comportamental, desenvolvemos um equipamento para avaliar o limiar de dor por aplicação de pressão nos animais, que opera com melhor precisão que os instrumentos comerciais. Os mecanismos de fotoneuromodulação foram investigados por quantificação de Trifosfato de Adenosina (ATP), imunofluorescência e marcação com hematoxilina-eosina de tecidos encefálicos que foram visualizados por microscópio confocal. A iluminação transcraniana aumentou a produção de ATP e de Fosfatase ácida prostática (um analgésico endógeno) e reduziu a quantidade do neurotransmissor glutamato, responsável pela condução da informação nociceptiva. Por outro lado, não observamos alteração na concentração de tubulina, um dos constituintes do citoesqueleto, e a marcação com hematoxilina-eosina revelou que não houve dano ao tecido decorrente da iluminação. Os achados apresentados nesse estudo atestam a relevância e eficácia da fotoneuromodulação proveniente de iluminação transcraniana com laser de 808 nm para suprimir a nocicepção em camundongos. Esse estudo é pioneiro na elucidação dos mecanismos de ação da fotoneuromodulação da dor in vivo. / Low-level Light therapy (LLLT) can treat acute and chronic pain. Getting knowledge about the pain pathways and the photon-neuron interactions may contribute to a better understanding of this therapy. The nociception may be self-controlled by endogenous analgesics, natural opioids that block the release of excitatory neurotransmitters, and thus make a total and nonspecific sensory inhibition. It is known that LLLT can stimulate the release of these endogenous analgesics, so it temporarily inhibits axonal transport in small diameter fibers. The knowledge of light fluence through neural tissue is essential to test the discussed assumptions. However, due to the complexity of biological tissues, the calculation (or simulation) of light-tissue interactions is impractical. In order to overcome this problem, we developed an experimental setup to estimate the light fluence in a transcranial LLLT and to map the optical properties of rat brains. It was possible to differentiate cerebral tissues and to estimate the depth of light penetration, which is more than 20 mm. We found a decrease in pain evoked either by pressure, heat, cold or inflammation after transcranial LLLT in mice. For this animal behavioral study, we developed an equipment to assess the pain threshold with pressure stimulus, which operates with better precision than commercial instruments. The LLLT mechanisms were investigated by Adenosine triphosphate ATP quantification, immunofluorescence and haematoxylin and eosin staining of brain tissues which were imaged by confocal microscopy. The transcranial irradiation increased ATP and prostatic acid phosphatase (an endogenous analgesic) production and reduced the amount of glutamate, the neurotransmitter responsible for conducting nociceptive information. There was no change in the concentration of tubulin, a constituent of the cytoskeleton, and the haematoxylin and eosin staining revealed no tissue damage due to the irradiation. This study is pioneer in elucidating the mechanisms of in vivo photoneuromodulation of pain.