50 research outputs found

    Buccal alterations in diabetes mellitus

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    Long standing hyperglycaemia besides damaging the kidneys, eyes, nerves, blood vessels, heart, can also impair the function of the salivary glands leading to a reduction in the salivary flow. When salivary flow decreases, as a consequence of an acute hyperglycaemia, many buccal or oral alterations can occur such as: a) increased concentration of mucin and glucose; b) impaired production and/or action of many antimicrobial factors; c) absence of a metalloprotein called gustin, that contains zinc and is responsible for the constant maturation of taste papillae; d) bad taste; e) oral candidiasis f) increased cells exfoliation after contact, because of poor lubrication; g) increased proliferation of pathogenic microorganisms; h) coated tongue; i) halitosis; and many others may occur as a consequence of chronic hyperglycaemia: a) tongue alterations, generally a burning mouth; b) periodontal disease; c) white spots due to demineralization in the teeth; d) caries; e) delayed healing of wounds; f) greater tendency to infections; g) lichen planus; h) mucosa ulcerations. Buccal alterations found in diabetic patients, although not specific of this disease, have its incidence and progression increased when an inadequate glycaemic control is present

    Lateral forces on circularly polarizable particles near a surface

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    Optical forces allow manipulation of small particles and control of nanophotonic structures with light beams. While some techniques rely on structured light to move particles using field intensity gradients, acting locally, other optical forces can push particles on a wide area of illumination but only in the direction of light propagation. Here we show that spin orbit coupling, when the spin of the incident circularly polarized light is converted into lateral electromagnetic momentum, leads to a lateral optical force acting on particles placed above a substrate, associated with a recoil mechanical force. This counterintuitive force acts in a direction in which the illumination has neither a field gradient nor propagation. The force direction is switchable with the polarization of uniform, plane wave illumination, and its magnitude is comparable to other optical forces.This work has been supported, in part, by EPSRC (UK). 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    Vortices and turbulence in trapped atomic condensates

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    Photobiomodulation on the angiogenesis of skin wounds in rats using different light sources

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    Objective: The aim of this study was to compare the angiogenic effects of laser and light-emitting diode ( LED) illumination on wounds induced in rats, with varied fluence. Background Data: The LED is an alternative light source that accelerates wound healing, and its efficiency concerning the angiogenic effect was compared to low-level laser therapy ( LLLT). Methods: The experimental model consisted of a circular wound inflicted on the quadriceps of 120 rats, using a 15-mm-diameter "punch." Animals were divided randomly into five groups: two groups of laser, with dosages of 5 and 20 J/cm(2), respectively, two groups of LED, also with dosages of 5 and 20 J/cm(2), and a control group. Six hours after wound infliction, the treated groups received the diverse applications accordingly and were irradiated every 24 h. Angiogenesis was studied through histomorphometry on days 3, 7, 14, and 21 after the wounds were inflicted. Results: On days 3, 7, and 14, the proliferation of blood vessels in all irradiated groups was superior in comparison to those of the control group ( p < 0.05). Treatment with fluence of 5 J/cm(2) was better than the laser group with 20 J/cm(2) on day 21. Conclusion: Red LLLT and LED demonstrated expressive results in angiogenesis. Light coherence was shown not to be essential to angiogenesis. However, further studies are needed in order to investigate the photobiomodulatory effects of LED in relation to LLLT in various biological tissues.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.25210210

    Phototherapy and resistance training prevent sarcopenia in ovariectomized rats

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    Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq)The aim of this study was to histologically and biochemically analyze the effects of light-emitting diode therapy (LEDT) associated with resistance training to prevent sarcopenia in ovariectomized rats. Forty female Wistar rats (12 months old, 295-330 g) were bilaterally ovariectomized and divided into four groups (n = 10 per group): control-sedentary (C), resistance training (T), LEDT-sedentary (L), and LEDT plus resistance training (LT). Trained rats performed a 12-week water-jumping program (3 days per week) carrying a load equivalent to 50-80 % of their body mass strapped to their back. Depending on the group protocol, the LED device (850 nm, 100 mW, 120 J/cm(2), spot size 0.5 cm(2)) was used either as the only method or after the resistance training had been performed. The device was used in the single point contact mode (for 10 min). The irradiated region was the center of the greater trochanter of the right femur and the middle third of the rectus femoris muscle was subsequently analyzed histomorphometrically. Significant increases (p < 0.05) were noted for the muscle volume of the T (68.1 +/- 19.7 %), the L (74.1 +/- 5.1 %), and the LT (68.2 +/- 11.5 %) groups compared to the C group (60.4 +/- 5.5 %). There were also significant increases in the concentrations of IGF-1, IL-1, and TNF-alpha in the muscles of the treated groups (p < 0.05). Animals in the LT group showed a significant increase in IL-6 compared to T, L, and C groups (p < 0.05). These findings suggest that resistance training and LEDT can prevent sarcopenia in ovariectomized rats.28614671474Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq)Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq

    Thermography Applied During Exercises With or Without Infrared Light-Emitting Diode Irradiation: Individual and Comparative Analysis

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Objective: The aim of our study was to evaluate the cutaneous temperature during an exercise on a treadmill with or without infrared light-emitting diode (LED) irradiation in postmenopausal women. Background data: Thermography is an imaging technique in which radiation emitted by a body in the middle and far infrared spectrum is detected and associated with the temperature of the body's surface. Materials and methods: Eighteen postmenopausal women were randomly divided into two groups: (1) the LED group, which performed the exercises on a treadmill associated with phototherapy (n = 9) and; (2) the exercise group, which performed the exercises on a treadmill without additional phototherapy (n = 9). The irradiation parameters for each women's thigh were: array of 2000 infrared LEDs (850 nm) with an area of 1,110 cm(2), 100 W, 39 mW/cm(2), and 108 J/cm(2) for 45 min. The submaximal constant-speed exercise on the treadmill at intensities between 85% and 90% maximal heart rate (HRmax) with or without phototherapy were performed during 45 min, to perform the thermographic analysis. Thermography images were captured before the exercise (t = 0), after 10, 35, and 45 min of exercising (t = 10, t = 35, and t = 45) and at 5 min post-exercising (t = 50). Results: The LED group showed an increased cutaneous thigh temperature during the exercise (from 33.5 +/- 0.8 degrees C to 34.6 +/- 0.9 degrees C, p = 0.03), whereas the exercise group showed a reduced cutaneous temperature (from 33.5 +/- 0.6 to 32.7 +/- 0.7 degrees C, p = 0.02). The difference between the groups was significant (p < 0.05) at t = 35, t = 45, and t = 50. Conclusions: These data indicate an improved microcirculation, and can explain one possible mechanism of action of phototherapy associated with physical exercises.o TEXTO COMPLETO DESTE ARTIGO, ESTARÁ DISPONÍVEL À PARTIR DE AGOSTO DE 2015.317349355Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP [2008/578588-9, 98/14270-8]CNPq [573587/2008, 151008/2012-4
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