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1.
Lasers Med Sci ; 31(4): 741-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26984347

RESUMO

Photobiomodulation is proposed as a non-linear process, and only low-level laser therapy (LLLT) is assumed to stimulate exposed cells, whereas high powered laser and fluences can cause negative effects, exhausting the cell's energy reserve as a consequence of excessive photon-based stimulation. In our work, we investigated and compared the effects of 808-nm diode laser (CW) with a new flat-top handpiece. To this purpose, we tested the photobiomodulation effects of 1 and 3 J/cm(2) fluence, both generated by 100 mW or 1 W of laser power and of 64 J/cm(2) of fluence generated by 100 mW, 1 W, 1.5 W or 2 W, as expressed through oxygen consumption and ATP synthesis of Paramecium. Data collected indicates the incremental consumption of oxygen through irradiation with 3 J/cm(2)-100 mW or 64 J/cm(2)-1 W correlates with an increase in Paramecium ATP synthesis. The Paramecium respiration was inhibited by fluences 64 J/cm(2)-100 mW or 64 J/cm(2)-2 W and was followed by a decrease in the endogenous ATP concentration. The 1 J/cm(2)-100 mW or 1 W and 3 J/cm(2)-1 W did not affect mitochondrial activity. The results show that the fluence of 64 J/cm(2)-1 W more than the 3 J/cm(2)-100 mW causes greater efficiency in Paramecium mitochondria respiratory chain activity. Our results suggest that thanks to flat-top handpiece we used, high fluences by high-powered laser have to be reconsidered as an effective and non-invasive therapy. Possible associated benefits of deeper tissue penetration would increase treatment effectiveness and reduced irradiation time.


Assuntos
Lasers Semicondutores , Mitocôndrias/efeitos da radiação , Paramecium/efeitos da radiação , Trifosfato de Adenosina/biossíntese , Humanos , Mitocôndrias/metabolismo , Consumo de Oxigênio , Paramecium/metabolismo
2.
Altern Lab Anim ; 43(3): 155-62, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26256394

RESUMO

Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. Unfortunately, conflicting literature has led to the labelling of PBM as a complementary or alternative medicine approach. However, past and ongoing clinical and research studies by reputable investigators have re-established the merits of PBM as a genuine medical therapy, and the technique has, in the last decade, seen an exponential increase in the numbers of clinical instruments available, and their applications. This resurgence has led to a clear need for appropriate experimental models to test the burgeoning laser technology being developed for medical applications. In this context, an ethical model that employs the protozoan, Paramecium primaurelia, is proposed. We studied the possibility of using the measure of oxygen consumption to test PBM by irradiation with an infrared or near-infrared laser. The results show that an 808nm infrared laser diode (1W; 64J/cm²) affects cellular respiration in P. primaurelia, inducing, in the irradiated cells, a significantly (p < 0.05) increased oxygen consumption of about 40%. Our findings indicate that Paramecium can be an excellent tool in biological assays involving infrared and near-infrared PBM, as it combines the advantages of in vivo results with the practicality of in vitro testing. This test represents a fast, inexpensive and straightforward assay, which offers an alternative to both traditional in vivo testing and more expensive mammalian cellular cultures.


Assuntos
Alternativas aos Testes com Animais , Terapia com Luz de Baixa Intensidade , Consumo de Oxigênio/efeitos da radiação , Paramecium/efeitos da radiação , Respiração Celular/efeitos da radiação , Lasers Semicondutores , Lactuca
4.
Eur J Protistol ; 61(Pt A): 294-304, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28756937

RESUMO

Few studies exist to explore the potential photobiomodulation (PBM) effect of neodymium:yttrium-aluminium garnet (Nd:YAG) laser irradiation using a flat-top handpiece delivery system. In this study, we explored the photobiomodulation effect of that laser, on Paramecium primaurelia. The parameters for the different study groups were: 0.50W, 10Hz, 100msp, 30J/cm2; 0.75W, 10Hz, 100msp, 45J/cm2; 1.00W, 10Hz, 100msp, 60J/cm2; 1.25W, 10Hz, 100msp, 75J/cm2 and 1.50W, 10Hz, 100msp, 90J/cm2. Our results suggest that only the parameter 0.5W, 10Hz, 100msp, 30J/cm2 positively photobiomodulates the Paramecium cells inducing an increment in oxygen consumption, endogenous ATP synthesis and fission rate rhythm. Applying the laser energy with parameters of 1.25W, 10Hz, 100msp, 75J/cm2 and 1.50W, 10Hz, 100msp, 90J/cm2, induce adverse effect on the Paramecium cells, which protect themselves through the increase in Heat Shock Protein-70 (HSP70). The data presented in our work support our assumption that, when using appropriate parameters of irradiation, the 1064nm Nd:YAG laser with flat-top handpiece could be a valuable aid for effective clinical application of PBM.


Assuntos
Lasers de Estado Sólido , Paramecium/efeitos da radiação , Alumínio/química , Proliferação de Células/efeitos da radiação , Mitocôndrias/metabolismo , Neodímio/química , Consumo de Oxigênio/efeitos da radiação , Paramecium/citologia , Paramecium/metabolismo , Ítrio/química
5.
Photomed Laser Surg ; 35(3): 127-135, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28056208

RESUMO

OBJECTIVE: The aim of this study was to investigate the photobiomodulation (PBM) effect of the 808 nm diode laser irradiation on spermatozoa, eggs, fertilized eggs, embryos, and larvae of Paracentrotus lividus, using two different power settings. BACKGROUND DATA: Studies have shown the possible use of PBM in artificial insemination. These have shown the potential effect of low-power laser irradiation on spermatozoa, while there are few studies on the effect of laser photonic energy on oocytes and almost no reports on the influence of lasers in embryogenesis. METHODS: P. lividus gametes, zygotes, embryos, and larvae were irradiated using the 808 nm diode laser (fluence 64 J/cm2 using 1 W or 192 J/cm2 with 3 W) with a flat-top hand-piece delivery, compared to a control without laser irradiation (0 J/cm2-0 W). The fertilization rate and the early developmental stages were investigated. RESULTS: The fertilization ability was not affected by the sperm/egg irradiation. At the gastrula stage, no significant differences were observed compared with the control samples. In the late pluteus stage, there were no differences in the developmental percentage observed between the control and the treated samples (1 W), with the exception of larvae from gastrulae and larvae, which were irradiated at 3 W. CONCLUSIONS: This study has demonstrated that both the 64 J/cm2-1 W and the 192 J/cm2-3 W do not induce morphological damage on the irradiated P. lividus gametes whose zygotes generate normal embryos and larvae. Our data therefore support the assumption to use higher fluence in preliminary studies on in vitro fertilization.


Assuntos
Ouriços-do-Mar/efeitos da radiação , Espermatozoides/efeitos da radiação , Tocoferóis , Animais , Desenvolvimento Embrionário/efeitos da radiação , Fertilização/efeitos da radiação , Larva , Masculino , Ouriços-do-Mar/fisiologia
6.
Photomed Laser Surg ; 34(11): 564-571, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27622977

RESUMO

OBJECTIVE: Photobiomodulation is proposed as a non-linear process. Only the action of light at a low intensity and fluence is assumed to have stimulation on cells; whereas a higher light intensity and fluence generates negative effects, exhausting the cell's energy reserve as a consequence of a too strong stimulation. In our work, we detected the photobiomodulatory effect of an 808-nm higher-fluence diode laser [64 J/cm2-1 W, continuous wave (CW)] irradiated by a flat-top handpiece on mitochondria activities, such as oxygen consumption, activity of mitochondria complexes I, II, III, and IV, and cytochrome c as well as ATP synthesis. MATERIALS AND METHODS: The experiments are performed by standard procedure on mitochondria purified from bovine liver. RESULTS: Our higher-fluence diode laser positively photobiomodulates the mitochondria oxygen consumption, the activity of the complexes III and IV, and the ATP production, with a P/O = 2.6. The other activities are not influenced. CONCLUSION: Our data show for the first time that even the higher fluences (64 J/cm2-1 W), similar to the low fluences, can photobiostimulate the mitochondria respiratory chain without uncoupling them and can induce an increment in the ATP production. These results suggest that the negative effects of higher fluences observed to date are not unequivocally due to higher fluence per se but might be a consequence of the irradiation carried by handpieces with a Gaussian profile.


Assuntos
Lasers Semicondutores , Fígado/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Mitocôndrias/efeitos da radiação , Trifosfato de Adenosina/metabolismo , Animais , Bovinos , Células Cultivadas , Desenho de Equipamento , Fígado/citologia , Fígado/metabolismo , Consumo de Oxigênio/fisiologia , Consumo de Oxigênio/efeitos da radiação , Paramecium/metabolismo , Paramecium/efeitos da radiação , Sensibilidade e Especificidade
7.
Photochem Photobiol ; 92(6): 854-862, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27716941

RESUMO

In Paramecium, cilia beating is correlated to intracellular calcium concentration ([Ca2+ ]i) and nitric oxide (NO) synthesis. Recent findings affirm that photobiomodulation (PBM) can transiently increase the [Ca2+ ]i in mammalian cells. In this study, we investigated the effect of both 808 and 980 nm diode laser irradiated with flat-top hand-piece on [Ca2+ ]i and NO production of Paramecium primaurelia, to provide basic information for the development of new therapeutic approaches. In the experiments, the laser power in CW varied (0.1; 0.5; 1; and 1.5 W) to generate the following respective fluences: 6.4; 32; 64; and 96 J cm-2 . The 6.4 J cm-2 did not induce PBM if irradiated by both 808 and 980 nm diode laser. Conversely, the 32 J cm-2 fluence had no effect on Paramecium cells if irradiated by the 808 nm laser, while if irradiated by the 980 nm laser induced increment in swimming speed (suggesting an effect on the [Ca2+ ]i, NO production, similar to the 64 J cm-2 with the 808 nm wavelength). The more evident discordance occurred with the 96 J cm-2 fluence, which had the more efficient effect on PBM among the parameters if irradiated with the 808 nm laser and killed the Paramecium cells if irradiated by the 980 nm laser. Lastly, the 980 nm and 64 or 96 J cm-2 were the only parameters to induce a release of stored calcium.


Assuntos
Cálcio/análise , Raios Infravermelhos , Lasers Semicondutores , Óxido Nítrico/metabolismo , Paramecium/metabolismo , Líquido Intracelular/química , Óxido Nítrico/química , Fotobiologia
8.
Photomed Laser Surg ; 33(1): 35-40, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25555194

RESUMO

OBJECTIVE: Photobiostimulation and photobiomodulation (PBM) are terms applied to the manipulation of cellular behavior using low intensity light sources, which works on the principle of inducing a biological response through energy transfer. The aim of this investigation was to identify a laboratory assay to test the effect of an infrared diode laser light (808 nm) on cell fission rate. MATERIALS AND METHODS: Sixty cells of Paramecium primaurelia were divided in two groups of 30. The first group (test group) was irradiated, at a temperature of 24°C, for 50 sec by a 808 nm diode laser with a flat top handpiece [1 cm of spot diameter, 1 W in continuous wave (CW), 50 sec irradiation time, 64 J/cm(2) of fluence]. The second group (control group) received no laser irradiation. All cells were transferred onto a depression slide, fed, and incubated in a moist chamber at a temperature of 24°C. The cells were exposed and monitored for 10 consecutive fission rates. Changes in temperature and pH were also evaluated. RESULTS: The exposed cells had a fission rate rhythm faster than the control cells, showing a binary fission significantly (p<0.05) shorter than unexposed cells. No significant effects of laser irradiation on pH and temperature of Paramecium's lettuce infusion medium were observed. CONCLUSIONS: The 808 nm infrared diode laser light, at the irradiation parameters used in our work, results in a precocious fission rate in P. primaurelia cells, probably through an increase in metabolic activity, secondary to an energy transfer.


Assuntos
Bioensaio/métodos , Lasers Semicondutores , Terapia com Luz de Baixa Intensidade/instrumentação , Paramecium/efeitos da radiação , Transferência de Energia
9.
Photochem Photobiol ; 91(5): 1150-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26118482

RESUMO

Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. To clarify the mechanisms of action of PBM at cellular and organism levels, we investigated its effect on Paramecium primaurelia (Protozoa) irradiated by an 808 nm infrared diode laser with a flat-top handpiece (1 W in CW). Our results led to the conclusion that: (1) the 808 nm laser stimulates the P. primaurelia without a thermal effect, (2) the laser effect is demonstrated by an increase in swimming speed and in food vacuole formation, (3) the laser treatment affects endogenous adenosine triphosphate (ATP) production in a positive way, (4) the effects of irradiation dose suggest an optimum exposure time of 50 s (64 J cm(-2) of fluence) to stimulate the Paramecium cells; irradiation of 25 s shows no effect or only mild effects and irradiation up to 100 s does not increase the effect observed with 50 s of treatment, (5) the increment of endogenous ATP concentration highlights the positive photobiomodulating effect of the 808 nm laser and the optimal irradiation conditions by the flat-top handpiece.


Assuntos
Trifosfato de Adenosina/metabolismo , Lasers Semicondutores , Paramecium/fisiologia , Paramecium/efeitos da radiação , Fagossomos/efeitos da radiação , Natação , Vacúolos/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação
10.
Photomed Laser Surg ; 27(4): 553-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19558311

RESUMO

PURPOSE: In pediatric patients with hemangiomas, vascular malformations, or lymphovenous malformations, therapeutic decisions frequently pose a challenge to surgeons, dermatologists, radiologists, and pathologists. We analyze the value of an interdisciplinary approach, and treatment of hemangiomas with an endolesional 980-nm diode laser. PATIENTS AND METHODS: Between 2000 and 2008 we provided interdisciplinary consultation for patients with hemangiomas, lymphangiomas, and vascular anomalies. We treated 250 patients with a 980-nm diode laser. In patients with hemangiomas and venous malformations, clinical diagnosis was confirmed by color Doppler flow imaging and magnetic resonance imaging; angiography was employed for patients with arteriovenous malformations. All patients were either treated by laser surgery or treated conservatively depending on lesion size and behavior. RESULTS: Two hundred fifty pediatric patients were treated; these included 160 patients with hemangiomas, 50 with vascular malformations, and 40 with lymphatic malformation. The treatment results were analyzed by evaluating the decrease in lesion size and the lesion's complete clinical disappearance. All patients had resolution except 38 for whom there was a reduction in lesion size that required a new session. CONCLUSIONS: The interdisciplinary approach increases diagnostic accuracy, and subsequently improves individual treatment for pediatric patients with hemangioma, lymphangioma, and vascular anomalies. The diode laser was found to be useful in the treatment of lesions in pediatric patients in terms of aesthetic results and resolution.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Hemangioma/cirurgia , Linfangioma/cirurgia , Malformações Vasculares/cirurgia , Adolescente , Criança , Feminino , Humanos , Lasers Semicondutores , Masculino
11.
Photomed Laser Surg ; 26(5): 451-3, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18922088

RESUMO

OBJECTIVE: Red and near-infrared laser irradiation is reported to have a range of biological effects on cultured cells and different tissues, leading to the hypothesis that laser light can affect energy metabolism. Increased adenosine triphosphate (ATP) synthesis has been reported in cultured cells and rat brain tissue after irradiation at 632.8 nm and 830 nm, respectively. This study investigated whether diode pulsed laser irradiation enhances ATP production in lymphocytes. MATERIALS AND METHODS: Aliquots (500 microL) of an extract of cultured lymphocytes of the Molt-4 cell line were irradiated with diode laser light (lambda = 904 nm, pulsed mode, 6 kHz frequency) with an average emission power of 10 mW for 60 min. A Spectra Physics M404 power meter was used to measure light intensity. Controls were treated similarly but not irradiated. The amount of ATP was measured by the luciferin-luciferase bioluminescent assay. RESULTS: The amount of ATP in irradiated cell cultures was 10.79 +/- 0.15 microg/L (SD; n = 10), and in non-irradiated cell cultures it was 8.81 +/- 0.13 microg/L (SD; n = 10). The average percentage increase of irradiated versus control cell cultures was about 22.4% +/- 0.56% SD (p < 0.001). CONCLUSION: This significant increase is probably due to laser irradiation; it cannot be attributed to any thermal effect, as the temperature during irradiation was maintained at 37.0 degrees +/- 0.5 degrees C. Thus the therapeutic effects of the biostimulating power of this type of laser are identified and its indications may be expanded.


Assuntos
Trifosfato de Adenosina/metabolismo , Raios Infravermelhos , Terapia com Luz de Baixa Intensidade , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Técnicas de Cultura de Células , Células Cultivadas , Humanos
12.
Rev. Círc. Odontol. Misiones ; 10(23): 29-31, ene.-mar. 1984.
Artigo em Espanhol | LILACS | ID: lil-55546
13.
Rev. Círc. Odontol. Misiones ; 10(23): 29-31, ene.-mar. 1984.
Artigo em Espanhol | BINACIS | ID: bin-30501
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