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The control of infectious diseases caused by biofilms is a continuing challenge for researchers due to the complexity of their microbial structures and therapeutic implications. Photodynamic therapy as an adjunctive anti-infective treatment has been described as a possible valid approach but has not been tested in polymicrobial biofilm models. This study evaluated the effect of photodynamic therapy in vitro with methylene blue (MB) 0.01% and red LEDs (λ = 660 nm, power density ≈ 330 mW/cm2, 2 mm distance from culture) on the metabolic activity and composition of a multispecies subgingival biofilm. Test Groups LED and MB + LED showed a more significant reduction in metabolic activity than the non-LED application group (~50 and 55%, respectively). Groups LED and MB equally affected (more than 80%) the total bacterial count in biofilms. No differences were noted in the bacterial biofilm composition between the groups. In vitro LED alone or the MB + LED combination reduced the metabolic activity of bacteria in polymicrobial biofilms and the total subgingival biofilm count.
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Laser-photobiomodulation (L-PBM) has been widely studied and its biomodulatory effects have been established on irradiated cells, increasing viability and proliferation and on damaged tissues. In addition, L-PBM may reduce and modulate the inflammatory process. The effect of 660-nm and 808-nm laser-photobiomodulation on bone repair around titanium dental implants placed in rat's femur was evaluated by histomorphometry. Twenty-seven Wistar rats were divided into 3 groups of nine animals: group C - non-irradiated control; group R - λ=660nm irradiated; and group IR - λ=808nm irradiated. Each group was further divided in 3 subgroups of three animals each, according to histomorphometry analysis in 3 days, 7 days, and 14 days after irradiation. Histological H.E.-stained slides were photographed, and bone matrix measured in new-formed bone area. Bone matrix histomorphometry analysis indicates that at 7 days in the irradiated groups (R and IR), a bigger area matrix was observed in relation to control group (C) (p=0.04 and p=0.048 respectively). On the other hand, at 14 days, control group (C) presented a bigger area than infrared irradiated (IR) (p=0.001) and red irradiated group (R) also showed a bigger area than infrared irradiated group (IR) (p=0.019). Histological analysis indicates that irradiated groups (R and IR) exhibited a faster bone tissue matrix production than control group.
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Terapia com Luz de Baixa Intensidade , Titânio , Animais , Fêmur/patologia , Lasers , Ratos , Ratos WistarRESUMO
BACKGROUND: The development of techniques in biomaterials design and production added to advanced surgical procedures which enabled better and more predictable clinical outcomes. Maxillary sinus floor augmentation (MSFA) is among the more studied bone-guided regeneration procedure in the literature. The MSFA could be considered the gold standard procedure for bone-guided regeneration as it provides suitable functional and aesthetic solutions to alveolar ridge atrophy due to tooth loss. PURPOSE: This study aimed to conduct a detailed histomorphometric evaluation of collagen production in SFAs bone-guided regeneration, using nano-hydroxyapatite/ß-tricalcium phosphate (nano-HA/ß-TCP) composite. PATIENTS AND METHODS: A 52-year-old female had the left upper second premolar condemned due to periodontal disease, then a tooth implant replacement was planned. Due to maxillary sinus pneumatization, the MSFA had to be done before implant placement. Nano-HA/ß-TCP composite (2g) was used in the MSFA procedure. After nine months of the healing process, during the Cone Morse implant installation process, bone samples were collected for histologic analysis (sirius red, hematoxylin/eosin, polarized microscopy). Six months after implant installation, a ceramic crown was installed according to the patient's request. RESULTS: Proper masticatory function and aesthetics were re-established. The histomorphometric evaluation indicated that nano-HA/ß-TCP composite did not show any area devoid of cellular activity in sirius red or hematoxylin/eosin staining and the percentage (%) of new bone collagen fibers was achieved using polarization technique evaluation. CONCLUSION: According to these results, nano-HA/ß-TCP composite presented clinical and histomorphometric properties suit to be used as bone-guided regeneration biomaterial in MSFA. Furthermore, nano-HA/ß-TCP composite provided a favorable nano-environment to bone cells, enhancing bone matrix production.
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Bone defects are a challenging clinical situation, and the development of hydroxyapatite-based biomaterials is a prolific research field that, in addition, can be joined by stem cells and growth factors in order to deal with the problem. This study compares the use of synthetic hydroxyapatite and xenograft, used pure or enriched with bone marrow mononuclear fraction for the regeneration of critical size bone defects in rat calvaria through histomorphometric (Masson's staining) and immunohistochemical (anti-VEGF, anti-osteopontin) analysis. Forty young adult male rats were divided into five groups (n = 8). Animals were submitted to critical size bone defects (Ø = 8 mm) in the temporoparietal region. In the control group, there was no biomaterial placement in the critical bone defects; in group 1, it was filled with synthetic hydroxyapatite; in group 2, it was filled with xenograft; in group 3, it was filled with synthetic hydroxyapatite, enriched with bone marrow mononuclear fraction (BMMF), and in group 4 it was filled with xenograft, enriched with BMMF. After eight weeks, all groups were euthanized, and histological section images were captured and analyzed. Data analysis showed that in groups 1, 2, 3 and 4 (received biomaterials and biomaterials plus BMMF), a significant enhancement in new bone matrix formation was observed in relation to the control group. However, BMMF-enriched groups did not differ from hydroxyapatite-based biomaterials-only groups. Therefore, in this experimental model, BMMF did not enhance hydroxyapatite-based biomaterials' potential to induce bone matrix and related mediators.
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BACKGROUND: Synthetic biomaterials have played an increasingly prominent role in the substitution of naturally derived biomaterials in current surgery practice. In vitro and in vivo characterization studies of new synthetic biomaterials are essential to analyze their physicochemical properties and the underlying mechanisms associated with the modulation of the inflammatory process and bone healing. PURPOSE: This study compares the in vivo tissue behavior of a synthetic biomaterial nano-hydroxyapatite/beta-tricalcium phosphate (nano-HA/ß-TCP mixture) and deproteinized bovine bone mineral (DBBM) in a rat calvarial defect model. The innovation of this work is in the comparative analysis of the effect of new synthetic and commercially xenogenic biomaterials on the inflammatory response, bone matrix gain, and stimulation of osteoclastogenesis and osteoblastogenesis. METHODS: Both biomaterials were inserted in rat defects. The animals were divided into three groups, in which calvarial defects were filled with xenogenic biomaterials (group 1) and synthetic biomaterials (group 2), or left unfilled (group 3, controls). Sixty days after calvarial bone defects filled with biomaterials, periodic acid Schiff (PAS) and Masson's trichrome staining, immunohistochemistry tumor necrosis factor-alpha (TNF-α), matrix metalloproteinase-9 (MMP-9), and electron microscopy analyses were conducted. RESULTS: Histomorphometric analysis revealed powerful effects such as a higher amount of proteinaceous matrix and higher levels of TNF-α and MMP-9 in bone defects treated with alloplastic nano-HA/ß-TCP mixture than xenogenicxenogic biomaterial, as well as collagen-proteinaceous material in association with hydroxyapatite crystalloids. CONCLUSION: These data indicate that the synthetic nano-HA/ß-TCP mixture enhanced bone formation/remodeling in rat calvarial bone defects. The nano-HA/ß-TCP did not present risks of cross-infection/disease transmission. The synthetic nano-hydroxyapatite/beta-tricalcium phosphate mixture presented adequate properties for guided bone regeneration and guided tissue regeneration for dental surgical procedures.
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Regeneração Óssea/efeitos dos fármacos , Hidroxiapatitas/química , Hidroxiapatitas/farmacologia , Nanoestruturas/química , Crânio/efeitos dos fármacos , Crânio/fisiologia , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Colágeno/metabolismo , Masculino , Osteogênese/efeitos dos fármacos , Ratos , Crânio/metabolismo , Crânio/patologiaRESUMO
Nowadays, we can observe a worldwide trend towards the development of synthetic biomaterials. Several studies have been conducted to better understand the cellular mechanisms involved in the processes of inflammation and bone healing related to living tissues. The aim of this study was to evaluate tissue behaviors of two different types of biomaterials: synthetic nano-hydroxyapatite/beta-tricalcium phosphate composite and bone xenograft in sub-critical bone defects in rat calvaria. Twenty-four rats underwent experimental surgery in which two 3 mm defects in each cavity were tested. Rats were divided into two groups: Group 1 used xenogen hydroxyapatite (Bio Oss™); Group 2 used synthetic nano-hydroxyapatite/beta-tricalcium phosphate (Blue Bone™). Sixty days after surgery, calvaria bone defects were filled with biomaterial, animals were euthanized, and tissues were stained with Masson's trichrome and periodic acid-Schiff (PAS) techniques, immune-labeled with anti-TNF-α and anti-MMP-9, and electron microscopy analyses were also performed. Histomorphometric analysis indicated a greater presence of protein matrix in Group 2, in addition to higher levels of TNF-α and MMP-9. Ultrastructural analysis showed that biomaterial fibroblasts were associated with the tissue regeneration stage. Paired statistical data indicated that Blue Bone™ can improve bone formation/remodeling when compared to biomaterials of xenogenous origin.
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OBJECTIVE: To compare the effects of photobiomodulation therapy (PBMT) and pharmacological therapy (glucocorticoids and non-steroidal anti-inflammatory drugs) applied alone and in different combinations in mdx mice. METHODS: The animals were randomized and divided into seven experimental groups treated with placebo, PBMT, prednisone, non-steroidal anti-inflammatory drug (NSAIDs), PBMT plus prednisone and PBMT plus NSAID. Wild type animals were used as control. All treatments were performed during 14 consecutive weeks. Muscular morphology, protein expression of dystrophin and functional performance were assessed at the end of the last treatment. RESULTS: Both treatments with prednisone and PBMT applied alone or combined, were effective in preserving muscular morphology. In addition, the treatments with PBMT (p = 0.0005), PBMT plus prednisone (p = 0.0048) and PBMT plus NSAID (p = 0.0021) increased dystrophin gene expression compared to placebo-control group. However, in the functional performance the PBMT presented better results compared to glucocorticoids (p<0.0001). In contrast, the use of NSAIDs did not appear to add benefits to skeletal muscle tissue in mdx mice. CONCLUSION: We believe that the promising and optimistic results about the PBMT in skeletal muscle of mdx mice may in the future contribute to this therapy to be considered a safe alternative for patients with Duchenne Muscular Dystrophy (DMD) in a washout period (between treatment periods with glucocorticoids), allowing them to remain receiving effective and safe treatment in this period, avoiding at this way periods without administration of any treatment.
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Distrofina/genética , Terapia com Luz de Baixa Intensidade , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/efeitos da radiação , Distrofia Muscular de Duchenne/terapia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Terapia Combinada , Modelos Animais de Doenças , Progressão da Doença , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Glucocorticoides/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos mdx , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/fisiopatologia , Prednisona/farmacologiaRESUMO
CONTEXT: Cancer Pain is considered a common and significant clinical problem in malignant neoplasms, comprising 20% to 50% of all patients with tumor progression. Laser photobiomodulation (L-PBM) has been used in a multitude of pain events, ranging from acute trauma to chronic articular. However, L-PBM has never been tested in cancer pain. OBJECTIVES: Evaluate hyperalgesia, edema, COX-1, COX-2, IL-10, and Bdkrb1 mRNA in low-level laser irradiated Walker-256 tumor-bearing rats. METHODS: Rat hind paw injected with Walker Tumor-256 (W-256) and divided into six groups of 6 rats: G1 (control) - W-256 injected, G2- W-256â¯+â¯Nimesulide, G3- W-256â¯+â¯1â¯J, G4- W-256â¯+â¯3â¯Jand G5- W256â¯+â¯6â¯J. Laser parameters: λâ¯=â¯660â¯nm, 3.57â¯W/cm2, Øâ¯=â¯0.028â¯cm2. Mechanical hyperalgesia was evaluated by Randall-Selitto test. Plethysmography measured edema; mRNA levels of COX-1, COX-2, IL-10, and Bdkrb1were analyzed. RESULTS: It was found that the W-256â¯+â¯1â¯J group showed a decrease in paw edema, a significant reduction in pain threshold. Higher levels of IL-10 and lower levels of COX-2 and Bdkrb1 were observed. CONCLUSION: Results suggest that 1â¯Jâ¯L-PBM reduced the expression of COX-2 and Bdkrb1 and increasing IL-10 gene expression, promoting analgesia to close levels to nimesulide.
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Hiperalgesia/radioterapia , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade , Animais , Carcinoma 256 de Walker/metabolismo , Carcinoma 256 de Walker/patologia , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Edema/metabolismo , Edema/patologia , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Masculino , Pletismografia , Ratos , Ratos Wistar , Transplante HeterólogoRESUMO
Orthodontic brackets, specifically in their slots, are responsible for receiving active orthodontic forces and transferring them to the teeth to be moved. The presence of an altered slot or inaccurate dimensions can influence the mechanical relationship between the bracket and archwire, interfering with the biomechanics of tooth movement. The objective of this study was by comparing the accuracy of slot placement of upper right lateral incisor metal brackets for Bioprogressive Ricketts therapy from five trademarks. The following characteristics were evaluated: height, torque, and internal parallelism of the walls of the slot. The sample included 75 brackets, 15 each from the following trademarks: 3M Abzil, Forestadent, Morelli Rocky Mountain Orthodontics, and Tecnident. Images of the slot profiles were obtained through standardized techniques using scanning electron microscopy, measured by the AutoCAD 2017 software, and compared to Ricketts prescription, respecting standard deviation with the technical and tolerance parameters present in standard ISO 27020. The results indicated that most of the evaluated characteristics were in accordance with the standard parameters, considering the tolerance adopted. There were exceptions found to this pattern of precision in the 3M Abzil brackets with regard to torque variation, and the Morelli brackets in relation to height variation and parallelism between the walls of the slot. Considering the measured dimensional characteristics, the metal brackets used in Bioprogressive Ricketts therapy has satisfactory pattern accuracy; however, there are still some specific inaccuracies in brackets from certain brands that can require more attention during the detailing phase.
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Análise do Estresse Dentário/métodos , Incisivo/fisiologia , Braquetes Ortodônticos , Ortodontia/métodos , Humanos , Teste de Materiais , Fios Ortodônticos , Aço Inoxidável , Estresse Mecânico , Propriedades de Superfície , TorqueRESUMO
Introdução: Pacientes submetidos à radioterapia para tratamento de neoplasias malignas na região de cabeça e pescoço são propensos a desenvolver complicações orais como a cárie de radiação, que evolui rapidamente e é altamente destrutiva.É reconhecido que o seu desenvolvimento está associado a alterações pós-radioterápicas nas glândulas salivares maiores, o que resulta em hipossalivação e alteração nos constituintes salivares. No entanto, tem sido aceito que danos diretos causados pela radiação à estrutura dentária podem acelerar a progressão da cárie e estudos têm demonstrado alterações morfológicas e físicas em dentes humanos após radioterapia. Objetivo: Propõe-se apresentar um caso de cárie de radiação e os efeitos diretos da radioterapia na estrutura dentária. Relato de caso: Paciente masculino, 60 anos de idade, com queixa principal de fragilidade dentária; relatou história de carcinoma epidermóide em língua há 18 meses e que o protocolo de tratamento aplicado foi quimioterapia (38 sessões), radioterapia (38 sessões) e cirurgia. Ao exame físico, dentre as alterações observadas, destacou-se a presença de regiões cervicais dentárias enegrecidas com coroas bastante fragilizadas em todos os dentes remanescentes, características de cárie de radiação. Foi realizado um tratamento atraumático, que está em acompanhamento. Conclusões: A cárie de radiação tem como principal fator etiológico alterações salivares qualitativas e quantitativas. A discussão sobre os efeitos diretos da radioterapia sobre a estrutura dentária ainda é bastante polêmica na literatura odontológica. Desta forma, sugere-se que mais estudos sejam realizados de forma sistemática, de maneira mais completa e padronizada(AU)
Introducción: Los pacientes sometidos a radioterapia para el tratamiento de tumores malignos en la cabeza y el cuello son propensos a desarrollar complicaciones bucales, tales como caries de radiación que evoluciona rápidamente y es altamente destructiva. Se reconoce que el desarrollo se asocia con cambios posradioterapia en las glándulas salivales, que resulta en hiposalivación y el cambio en los componentes salivales. Sin embargo, se ha aceptado que los daños por radiación directa a la estructura dental puede acelerar la progresión de la caries y los estudios han demostrado cambios morfológicos y físicos en los dientes humanos después de la radioterapia. Objetivo: presentar un caso de caries de radiación y los efectos directos de la radiación en la estructura dental. Presentación del caso: Paciente masculino de 60 años de edad, se quejaba de fragilidad dental, con historia notificada de carcinoma de células escamosas en la lengua hace 18 meses y con protocolo de tratamiento aplicado de quimioterapia (38 sesiones), terapia de radiación (38 sesiones) y cirugía. En el examen físico, de los cambios observados, se destacó la presencia de regiones cervicales dentarias negruzcas con coronas bastante frágiles en todos los dientes restantes, características de caries de radiación. El tratamiento atraumático se realizó y el paciente está bajo observación. Conclusiones: los cambios cuantitativos y cualitativos salivales actúa como el factor causal principal de la caries por radiación. La discusión acerca de los efectos directos de la radiación sobre la estructura del diente es todavía muy controvertido en la literatura dental. Por lo tanto, se sugiere que se realicen estudios adicionales de manera sistemática, más completa y estandarizada(AU)
Introduction: Patients undergoing radiotherapy as treatment for malignant head and neck tumors are prone to develop oral complications such as radiation caries, which evolves rapidly and is highly destructive. Such development is known to be caused by post-radiotherapy alterations in salivary glands resulting in hyposalivation and changes in salivary components. However, it has been accepted that damage by direct radiation to the dental structure may hasten the progress of caries development, and studies have shown the morphological and physical changes occurring in human teeth after radiotherapy. Objective: Present a case of radiation caries and the direct effects of radiation on dental structure. Case presentation: A 60-year-old male patient complains of dental fragility. The patient was diagnosed with squamous-cell carcinoma of the tongue 18 months ago and indicated chemotherapy (38 sessions), radiotherapy (38 sessions) and surgery. Physical examination revealed among other changes the presence of blackish cervical areas with quite fragile crowns in all remaining teeth, which are characteristic of radiation caries. Non-traumatic treatment was performed and the patient is now under observation. Conclusions: Salivary quantitative and qualitative changes are the main cause of radiation caries. Discussion about the direct effects of radiation on dental structure is still quite controversial in the literature on the topic. It is therefore suggested to conduct further studies in a more systematic, complete and standardized manner(AU)
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Humanos , Masculino , Pessoa de Meia-Idade , Suscetibilidade à Cárie Dentária/efeitos da radiação , Doenças da Boca/complicações , Neoplasias da Língua/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapiaRESUMO
It is well established that laser phototherapy (LP) is contraindicated directly over cancer cells, due to its bio modulatory effects in cell and blood vessel proliferation. The aim of the present study was to analyze the influence of typical low-level laser therapy (LLLT) and high intensity laser therapy (HILT) and an in-between dose of 9 J on collagen fibers and blood vessels content in melanoma tumors (B16F10) implanted in mice. Melanoma tumor cells were injected in male Balb C mice which were distributed in four groups: control (no irradiated) or irradiated by 3, 9, or 21 J (150; 450, or 1050 J/cm2). LP was performed in daily sessions for 3 days with a InGaAlP-660 nm (mean output: 50 mW, spot size: 2 mm2). Tumor volume was analyzed using (1) picrosirius staining to quantify collagen fibers content and (2) Verhoeff's method to quantify blood vessels content. Tumor growth outcome measured in the 3-J group was not significantly different from controls. Nine and 21-J groups, presented significant and dose-dependent increases in tumor volume. Quantitative analysis of the intensity of collagen fibers and their organization in stroma and peri-tumoral microenvironment showed significant differences between irradiated and control group. Blood vessels count of 21-J group outnumbered the other groups. High doses (≥ 9 J) of LP showed a dose-dependent tumor growth, different collagen fibers characteristics, and eventually blood vessel growth, while a typical LLLT dose (3 J) appeared harmless on melanoma cell activity.
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Tecido Conjuntivo/patologia , Tecido Conjuntivo/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Melanoma Experimental/patologia , Animais , Proliferação de Células/efeitos da radiação , Colágeno Tipo I/metabolismo , Relação Dose-Resposta à Radiação , Colágenos Fibrilares/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Coloração e Rotulagem , Células Estromais/patologia , Células Estromais/efeitos da radiação , Carga Tumoral/efeitos da radiaçãoRESUMO
To evaluate low-level laser therapy (LLLT) as an adjunct to enhance postoperative mouth opening after orthognathic surgery. Prospective clinical trial of 82 patients allocated into an intervention group (laser, LG) and a control group (no laser, CG) and subgroups according to the procedure type : (1) surgically assisted rapid maxillary expansion (SARME); (2) maxillary surgery; (3) mandibular surgery; or (4) bimaxillary surgery. LG patients received LLLT immediately after surgery and every 24 h thereafter for 3 days, using a gallium-aluminum-arsenide (GaAlAs) diode laser (780 nm, 28 spots, 14 on each side of the face, output power 2 J/spot). Maximum mouth opening was measured using digital calipers at five time points: preoperative baseline and postoperative days 2, 7, 14, and 21. ANOVA was used to evaluate difference in mouth opening across groups. Significance was accepted at P ≤ 0.05. Final average mouth opening differed between women (GL1 = 94.24%, GC1 = 89.54%, GL2 = 69.39%; GC2 = 68.46%; GL3 = 65.11%; GC3 = 58.64%; GL4 = 61.85%; GC4 = 57.11%) and men (GL1 = 86.92%, GC1 = 102.44%, GL2 = 77.56%; GC2 = 81.65%; GL3 = 80.29%; GC3 = 67.63%; GL4 = 66.93%; GC4 = 55.31%). There were no significant differences between the SARME and isolated maxillary/mandibular surgery groups. In the bimaxillary groups, average mouth opening was increased in all patients who received LLLT, significantly so in male patients. LLLT with a GaAlAs diode laser (780 nm) did not affect postoperative mouth opening after SARME, isolated maxillary surgery, or isolated mandibular surgery. However, it improved mouth opening in men who had undergone bimaxillary orthognathic surgery.
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Lasers Semicondutores/uso terapêutico , Boca/efeitos da radiação , Cirurgia Ortognática , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnica de Expansão Palatina , Estudos Prospectivos , Adulto JovemRESUMO
BACKGROUND: Tendinopathy is characterized by pain, edema, and structural changes in tendon tissue. OBJECTIVE: In this animal study we decided to compare the short- and medium-term effects of low-level laser therapy (LLLT), dexamethasone, and diclofenac on inflammation and tendon tissue repair in collagenase-induced tendinitis. MATERIALS AND METHODS: Two hundred five female Wistar rats were randomly divided into five groups. Animals in the control group were given a saline injection and the experimental groups received a collagenase injection (100 µg/tendon) in the peritendinous Achilles and received no treatment, LLLT (3 J, 810 nm, 100 mW), diclofenac (1.1 mg/kg), or dexamethasone (0.02 mg/kg). Histological analyses were performed at 10 time points up to 60 days (n = 5/group each time point), and included an assessment of the severity of inflammation, collagen fiber content, and organization. RESULTS: Collagenase injection induced a severe inflammatory reaction with significant reduction in collagen content for 48 h, and disorientation of collagen fibers lasting between 14 and 21 days. Diclofenac and dexamethasone reduced inflammatory signs during the first 2 days, although there was prolongation of the inflammatory phase and slower normalization of tendon quality, particularly in the dexamethasone group. LLLT prevented hemorrhage, reduced inflammation severity, and preserved tendon morphology compared with the other groups. CONCLUSIONS: LLLT showed a significant superiority over commonly used anti-inflammatory pharmaceutical agents in acute collagenase-induced tendinitis.
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Tendão do Calcâneo , Anti-Inflamatórios/uso terapêutico , Terapia com Luz de Baixa Intensidade , Tendinopatia/terapia , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , Animais , Colagenases , Modelos Animais de Doenças , Feminino , Ratos WistarRESUMO
This study aimed to analyze the protective effects of photobiomodulation therapy (PBMT) with combination of low-level laser therapy (LLLT) and light emitting diode therapy (LEDT) on skeletal muscle tissue to delay dystrophy progression in mdx mice (DMD mdx ). To this aim, mice were randomly divided into five different experimental groups: wild type (WT), placebo-control (DMD mdx ), PBMT with doses of 1 J (DMD mdx ), 3 J (DMD mdx ), and 10 J (DMD mdx ). PBMT was performed employing a cluster probe with 9 diodes (1 x 905nm super-pulsed laser diode; 4 x 875nm infrared LEDs; and 4 x 640nm red LEDs, manufactured by Multi Radiance Medical®, Solon - OH, USA), 3 times a week for 14 weeks. PBMT was applied on a single point (tibialis anterior muscle-bilaterally). We analyzed functional performance, muscle morphology, and gene and protein expression of dystrophin. PBMT with a 10 J dose significantly improved (p < 0.001) functional performance compared to all other experimental groups. Muscle morphology was improved by all PBMT doses, with better outcomes with the 3 and 10 J doses. Gene expression of dystrophin was significantly increased with 3 J (p < 0.01) and 10 J (p < 0.01) doses when compared to placebo-control group. Regarding protein expression of dystrophin, 3 J (p < 0.001) and 10 J (p < 0.05) doses also significantly showed increase compared to placebo-control group. We conclude that PBMT can mainly preserve muscle morphology and improve muscular function of mdx mice through modulation of gene and protein expression of dystrophin. Furthermore, since PBMT is a non-pharmacological treatment which does not present side effects and is easy to handle, it can be seen as a promising tool for treating Duchenne's muscular dystrophy.
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Distrofina/metabolismo , Terapia com Luz de Baixa Intensidade/métodos , Músculo Esquelético/fisiopatologia , Músculo Esquelético/efeitos da radiação , Distrofia Muscular de Duchenne/fisiopatologia , Distrofia Muscular de Duchenne/radioterapia , Animais , Relação Dose-Resposta à Radiação , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Placebos , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Pressure ulcers (PU) are wounds located mainly on bone surfaces where the tissue under pressure suffers ischemia leading to cellular lesion and necrosis , its causes and the healing process depend on several factors. The aim of this study was evaluating the gene expression of inflammatory/reparative factors: IL6, TNF, VEGF, and TGF, which take part in the tissue healing process under effects of low-level laser therapy (LLLT). In order to perform lesion area analysis, PUs were photographed and computer analyzed. Biochemical analysis was performed sa.mpling ulcer border tissue obtained through biopsy before and after laser therapy and quantitative real-time PCR (qRT-PCR) analysis. The study comprised eight individuals, mean age sixty-two years old, and sacroiliac and calcaneous PU, classified as degree III and IV according to the National Pressure Ulcer Advisory Panel (NPUAP). PUs were irradiated with low-level laser (InGaAIP, 100 mW, 660 nm), energy density 2 J/cm2, once a day, with intervals of 24 h, totaling 12 applications. The lesion area analysis revealed averaged improvement of the granulation tissue size up to 50% from pre- to post-treatment. qRT-PCR analysis revealed that IL6 values were not significantly different before and after treatment, TNF gene expression was reduced, and VEFG and TGF-ß gene expression increased after treatment. After LLLT, wounds presented improvement in gross appearance, with increase in factors VEFG and TGF-ß, and reduction of TNF; despite our promising results, they have to be analyzed carefully as this study did not have a control group.
Assuntos
Biomarcadores/metabolismo , Diabetes Mellitus/genética , Regulação da Expressão Gênica , Inflamação/genética , Terapia com Luz de Baixa Intensidade , Úlcera por Pressão/genética , Úlcera por Pressão/radioterapia , Cicatrização/efeitos da radiação , Diabetes Mellitus/radioterapia , Feminino , Tecido de Granulação/patologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/genéticaRESUMO
Background: Orthodontics of the 21st century requires aesthetic, painless, predictable, and quick treatments. This demand for faster results generated orthodontic movement acceleration protocols (OMAPs); among other OMAPs we present low-level laser (LLL) as a candidate. Objective: To evaluate levels of interleukin (IL)-1, IL-10, and type 1 collagen in the periodontal ligament of first molars of rats subjected to orthodontic traction with and without LLL irradiation, compared with untreated controls (CO), and to evaluate whether the dose of LLL used in this work is eligible as an OMAP. Materials and methods: A total of 35 male Wistar rats were distributed into three groups: group 1 NI (nonirradiated) n = 15, group 2 IR (laser irradiated using 5 J, 177 J/cm2, and 100 mW applied in contact to the vestibular mesial, vestibular distal, and palatal faces of gum tissue around molar region for 50 sec each point, for 3 consecutive days, immediately 24 and 48 h after orthodontic device placement.) n = 15, and group 3 CO n = 5; groups 1 and 2 were subjected to orthodontic force and each group was divided into three subgroups that were sacrificed after 3, 5, and 7 days, IL-1/10 and COL-1 levels were analyzed. Results: In the IR group, levels of IL-1/10 and COL-1 showed peak anticipation after LLL irradiation compared with those in the NI and CO groups. Conclusions: These results can also infer that this dose of LLL can be used as an OMAP.
Assuntos
Terapia a Laser/métodos , Terapia com Luz de Baixa Intensidade/métodos , Técnicas de Movimentação Dentária , Animais , Colágeno Tipo I/análise , Interleucinas/análise , Masculino , Dente Molar/química , Ligamento Periodontal/química , Ratos , Ratos WistarRESUMO
Laser photobiomodulation or low-level laser therapy (LLLT) is recognized worldwide for its expansive use in medicine. LLLT has been reported to increase enzymatic activity, increasing the mitochondrial transmembrane potential, leading to an increased energy availability and signal transduction. Nevertheless, an inhibitory effect is also observed by the production of excessive ROS which can result the shutdown of mitochondrial energy production, and finally to apoptosis. However, the mechanism of apoptosis induced by LLLT is still not well understood. The main objective of the present study was to investigate the hypothesis that LLLT induces oxidative stress and stimulates the generation of pro-inflammatory markers interfering in tumor progression. METHODS: Seventy-two female Walker Tumor induced Wistar rats (eight weeks of age, 200g body weight) were used for this study. TW-256 cells were suspended in phosphate buffered saline and then subcutaneously inoculated at 1×107viabletumorcells/ml per rat into the right flank (tumor-bearing rats). After a period of 14days in order to assess the development of the solid tumor mass, the animals were randomized and distributed in four groups (n=8 animals/group): (1) Control or irradiated by LLLT (2) Laser 1J - 35,7J/cm2, (3) Laser 3J - 107,14J/cm2 and (4) Laser 6J - 214,28J/cm2; (Thera Laser - 660nm, 100mW DMC®, São Carlos, Brazil) at four equidistant points according to their respective treatment groups, conducted three times on alternate days. The regulation and expression of inflammatory mediators IL-1ß, IL-6, IL-10, TNF-α was assessed by ELISA and gene expression of COX-1, COX-2, iNOS, eNOS was analyzed by RT-PCR. RESULTS: We found that the 1Joule (J) treated group promoted a significant increase in the levels of different inflammatory markers IL-1ß, the gene expression of COX-2, iNOS, which was statistically different (p<0.05) when compared among different treatment and control groups. With Respect IL-6, IL-10, TNF-α levels statistically significant reduce was observed in 1Joule treated group when comparing to different energies groups and control group. CONCLUSION: Our results suggest the evidence 1J-35,7J/cm2 treatment was able to produce cytotoxic effects by generation of ROS causing acute inflammation and thus may be employed as the best energy dose associated with Photodynamic Therapy.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/radioterapia , Mediadores da Inflamação/metabolismo , Lasers de Estado Sólido , Terapia com Luz de Baixa Intensidade , Animais , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Expressão Gênica/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismoRESUMO
Musculoskeletal injuries are very frequent and are responsible for causing pain and impairment of muscle function, as well as significant functional limitations. In the acute phase, the most prescribed treatment is with non-steroidal anti-inflammatory drugs (NSAIDs), despite their questionable effectiveness. However, the use of photobiomodulation therapy (PBMT) in musculoskeletal disorders has been increasing in the last few years, and this therapy appears to be an interesting alternative to the traditional drugs. The objective of the present study was to evaluate and compare the effects of PBMT, with different application doses, and topical NSAIDs, under morphological and functional parameters, during an acute inflammatory process triggered by a controlled model of musculoskeletal injury induced via contusion in rats. Muscle injury was induced by means of a single trauma to the animals' anterior tibialis muscle. After 1 h, the rats were treated with PBMT (830 nm; continuous mode, with a power output of 100 mW; 3.57 W/cm2; 1 J-35.7 J/cm2, 3 J-107.1 J/cm2, and 9 J-321.4 J/cm2; 10, 30, and 90 s) or diclofenac sodium for topical use (1 g). Morphological analysis (histology) and functional analysis (muscle work) were performed, 6, 12, and 24 h after induction of the injury. PBMT, with all doses tested, improved morphological changes caused by trauma; however, the 9 J (321.4 J/cm2) dose was the most effective in organizing muscle fibers and cell nuclei. On the other hand, the use of diclofenac sodium produced only a slight improvement in morphological changes. Moreover, we observed a statistically significant increase of muscle work in the PBMT 3 J (107.1 J/cm2) group in relation to the injury group and the diclofenac group (p < 0.05). The results of the present study indicate that PBMT, with a dose of 3 J (107.1 J/cm2), is more effective than the other doses of PBMT tested and NSAIDs for topical use as a means to improve morphological and functional alterations due to muscle injury from contusion.
Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacologia , Contusões/complicações , Terapia com Luz de Baixa Intensidade/métodos , Músculo Esquelético/lesões , Músculo Esquelético/patologia , Administração Tópica , Animais , Diclofenaco/farmacologia , Masculino , Músculo Esquelético/fisiopatologia , Músculo Esquelético/efeitos da radiação , Ratos WistarRESUMO
Muscle injuries trigger an inflammatory process, releasing important biochemical markers for tissue regeneration. The use of non-steroidal anti-inflammatory drugs (NSAIDs) is the treatment of choice to promote pain relief due to muscle injury. NSAIDs exhibit several adverse effects and their efficacy is questionable. Photobiomodulation therapy (PBMT) has been demonstrated to effectively modulate inflammation induced from musculoskeletal disorders and may be used as an alternative to NSAIDs. Here, we assessed and compared the effects of different doses of PBMT and topical NSAIDs on biochemical parameters during an acute inflammatory process triggered by a controlled model of contusion-induced musculoskeletal injury in rats. Muscle injury was induced by trauma to the anterior tibial muscle of rats. After 1 h, rats were treated with PBMT (830 nm, continuous mode, 100 mW of power, 35.71 W/cm2; 1, 3, and 9 J; 10, 30, and 90 s) or diclofenac sodium (1 g). Our results demonstrated that PBMT, 1 J (35.7 J/cm2), 3 J (107.1 J/cm2), and 9 J (321.4 J/cm2) reduced the expression of tumor necrosis factor alpha (TNF-α) and cyclooxygenase-2 (COX-2) genes at all assessed times as compared to the injury and diclofenac groups (p < 0.05). The diclofenac group showed reduced levels of COX-2 only in relation to the injury group (p < 0.05). COX-2 protein expression remained unchanged with all therapies except with PBMT at a 3-J dose at 12 h (p < 0.05 compared to the injury group). In addition, PBMT (1, 3, and 9 J) effectively reduced levels of cytokines TNF-α, interleukin (IL)-1ß, and IL-6 at all assessed times as compared to the injury and diclofenac groups (p < 0.05). Thus, PBMT at a 3-J dose was more effective than other doses of PBMT and topical NSAIDs in the modulation of the inflammatory process caused by muscle contusion injuries.
Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Contusões/tratamento farmacológico , Contusões/radioterapia , Terapia com Luz de Baixa Intensidade/métodos , Músculo Esquelético/lesões , Administração Tópica , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Biomarcadores/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Diclofenaco/farmacologia , Diclofenaco/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/efeitos da radiação , Ratos Wistar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND AND OBJECTIVE: 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. MATERIALS AND METHODS: 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. RESULTS: 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-1ß) and the combined intervention groups (↓IL-1ß, ↓TNF-α, ↑IL-6). It was also found that cryotherapy followed by LLLT was the only treatment that significantly (p < 0.05) improved the biomechanical parameters of force (N) and displacement (mm) at the tendon rupture and corresponded with the best histological scores of all of the treatment groups. CONCLUSIONS: Our results demonstrate that 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.