Effectiveness of Laser treatment at acupuncture sites compared to traditional acupuncture in the treatment of peripheral artery disease.

Cardiovascular diseases are the main causes of mortality, not only in Brazil, but around the world. The use of acupuncture as a complementary and alternative treatment for cardiovascular diseases has been suggested for animals as well as human beings. Possible advantages in using acupuncture are the low cost of treatment and low risks of collateral damage from a combination of acupuncture with other medical treatments. The purpose of this study is to assess the effect of traditional acupuncture with needles and laser acupuncture on arterial pressure and peripheral circulation of inferior limbs in patients with circulatory deficiency. Ten acupuncture points were stimulated in 40 individuals, being that 20 were stimulated by Aluminum gallium arsenide (AlGaAs) laser with emission in the red spectral region (650 nm) using an energy density of 2,4 J/cm2, and 20 were stimulated by systemic acupuncture needles. The analysis of peripheral circulation was performed based on the measurement of arterial pressure of the ankle and arms, using sphygmomanometer and Doppler equipment. The variance of the revascularization index of the laser acupuncture group was 0,057, and 0.030 for the needles group with p= 0,006. These results show that only those treated with laser acupuncture exhibit a significant increase in systolic pressure of their lower limbs, with a consequent improvement of the Revascularization Index, suggesting that different stimuli on acupuncture points generate different variations of peripheral resistance of lower limbs. is column.

The impact of photodynamic therapy on the viability of Streptococcus mutans in a planktonic culture.

OBJECTIVE: This study investigated the effect of photodynamic therapy (PDT) with toluidine blue O (TBO) and a light-emitting diode (LED) on the viability of Streptococcus mutans cells in a planktonic culture. BACKGROUND DATA: Growth of Streptococcus mutans is the first step in the development of tooth decay. The use of light and dyes promotes cellular death in a noninvasive way, reducing treatment time. METHODS: The LED used in this study had output power of 116 mW, its energy was 21 J, and the fluency was 2.18 J/cm(2). Samples were prepared and divided into five groups: (1) control group (-); (2) control group (+); (3) TBO; (4) LED; and (5) LED + TBO. RESULTS: One hundred percent of the bacteria were killed following irradiation with LED and TBO. The biofilm that formed on the glass surfaces was analyzed by SEM and colony count. CONCLUSIONS: It was demonstrated that PDT was efficient at killing microorganisms and preventing the formation of biofilms.

Effect of LLLT Ga-Al-As (685 nm) on LPS-induced inflammation of the airway and lung in the rat.

The purpose of this study was to investigate the effect of low level laser therapy (LLLT) on male Wistar rat trachea hyperreactivity (RTHR), bronchoalveolar lavage (BAL) and lung neutrophils influx after Gram-negative bacterial lipopolyssacharide (LPS) intravenous injection. The RTHR, BAL and lung neutrophils influx were measured over different intervals of time (90 min, 6 h, 24 h and 48 h). The energy density (ED) that produced an anti-inflammatory effect was 2.5 J/cm(2), reducing the maximal contractile response and the sensibility of trachea rings to methacholine after LPS. The same ED produced an anti-inflammatory effect on BAL and lung neutrophils influx. The Celecoxib COX-2 inhibitor reduced RTHR and the number of cells in BAL and lung neutrophils influx of rats treated with LPS. Celecoxib and LLLT reduced the PGE(2) and TXA(2) levels in the BAL of LPS-treated rats. Our results demonstrate that LLLT produced anti-inflammatory effects on RTHR, BAL and lung neutrophils influx in association with inhibition of COX-2-derived metabolites.

Analgesic effect of He-Ne (632.8 nm) low-level laser therapy on acute inflammatory pain.

OBJECTIVE: The aim of this study was to evaluate the analgesic effect of the low level laser therapy (LLLT) with a He-Ne laser on acute inflammatory pain, verifying the contribution of the peripheral opioid receptors and the action of LLLT on the hyperalgesia produced by the release of hyperalgesic mediators of inflammation. BACKGROUND DATA: All analgesic drugs have undesired effects. Because of that, other therapies are being investigated for treatment of the inflammatory pain. Among those, LLLT seems to be very promising. MATERIAL AND METHODS: Male Wistar rats were used. Three complementary experiments were done. (1) The inflammatory reaction was induced by the injection of carrageenin into one of the hind paws. Pain threshold and volume increase of the edema were measured by a pressure gauge and plethysmography, respectively. (2) The involvement of peripheral opioid receptors on the analgesic effect of the laser was evaluated by simultaneous injection of carrageenin and naloxone into one hind paw. (3) Hyperalgesia was induced by injecting PGE2 for the study of the effect of the laser on the sensitization increase of nociceptors. A He-Ne laser (632.8 nm) of 2.5 J/cm2 was used for irradiation. RESULTS: We found that He-Ne stimulation increased the pain threshold by a factor between 68% and 95% depending on the injected drug. We also observed a 54% reduction on the volume increase of the edema when it was irradiated. CONCLUSION: He-Ne LLLT inhibits the sensitization increase of nociceptors on the inflammatory process. The analgesic effect seems to involve hyperalgesic mediators instead of peripheral opioid receptors.

Side-viewing fiberoptic catheter for biospectroscopy applications.

Utilization of fiberoptic catheters can turn the Raman and fluorescence spectroscopy systems into powerful bio-medical diagnostic probes. An in vivo bio-chemical diagnosis of some important organs like the esophagus, intestine, lung branches, artery, etc., can be possible by developing fiber-probes with good signal collection capabilities, a good flexibility to scan different spatial regions of the sample and less background signals generated in the probes themselves. An in vivo diagnosis of endoluminal inner walls utilizing front-viewing catheters (FVC) is very difficult because the internal diameter of these organs do not allow (excitation and collection) flexibility to access the different spatial regions of the sample. In this work we have developed, different side-viewing catheter (SVC) probes with a very small distal tip (semi sphere, phi approximately 1.5 mm) and micro mirrors allow beam steering of the excitation and collected radiation at a 90 degree angle. Preliminary results of spectroscopic applications have been presented. Reflectance, fluorescence and Raman scattering measurements have been used to compare the efficiency of SVC with traditional FVC probes. The results demonstrate that the SVC probes not only exhibit more flexibility but also similar spectral characteristics and signal collection efficiencies in comparison with conventional FVC probes.

Effects of different protocol doses of low power gallium-aluminum-arsenate (Ga-Al-As) laser radiation (650 nm) on carrageenan induced rat paw ooedema.

The purpose of the present study was to investigate the effect of the low power laser therapy on the acute inflammatory process. Male Wistar rats were used. The rat paw oedema was induced by sub-plantar injection of carrageenan, the paw volume was measured before and 1, 2, 3 and 4 h after the injection using a hydroplethysmometer. To investigate the mechanism action of the Ga-Al-As laser on inflammatory oedema, parallel studies were performed using adrenallectomized rats or rats treated with sodium diclofenac. Different laser irradiation protocols were employed for specific energy densities (EDs), exposure times and repetition rates. The rats were irradiated with the Ga-Al-As laser during 80 s each hour. The ED that produced an anti-inflammatory effect were 1 and 2.5 J/cm(2), reducing the oedema by 27% (P<0.05) and 45.4% (P<0.01), respectively. The ED of 2.5 J/cm(2) produced anti-inflammatory effects similar to those produced by the cyclooxigenase inhibitor sodium diclofenac at a dose of 1 mg/kg. In adrenalectomized animals, the laser irradiation failed to inhibit the oedema. Our results suggest that low power laser irradiation possibly exerts its anti-inflammatory effects by stimulating the release of adrenal corticosteroid hormones.

Mitochondrial membrane potential after low-power laser irradiation.

We used the lipophilic cationic fluorescent dye 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazol-carbocyanine iodide (JC-1) to determine mitochondrial membrane potential (mdeltapsi) in Hep-2 cells after irradiation with low-power laser (lambda=635 nm). Through this methodology it was possible to analyze the variation on mitochondrial number and mdeltapsi, in cells irradiated for 100, 150 and 200 s with energy density of 100 mJ/cm(2). Our results show that JC-1 dye allows the identification of populations with different mitochondria morphology as well as the functionality of this organelle in the cells incubated for 1, 6 and 24 h, after irradiation with low-power laser.

Analysis of mitochondria, endoplasmic reticulum and actin filaments after PDT with AlPcS(4).

Photodynamic therapy (PDT) is a therapeutic modality for the treatment of tumors. This technique uses a visible light to activate a photosensitizer compounds, leading to a photo-oxidation process of biological tissue that can induce apoptosis or necrosis both in vivo and in vitro. However many of the cytotoxic effects remain an open question to be investigated. The cytotoxicity to specific cellular targets of classical photosensitizers used in the PDT in vitro has been analyzed in this work. The photosensitizing effects of Chloroaluminum Phthalocyanine Tetrasulfonate (AlPcS(4)) were studied on the mitochondria, cytoskeleton and endoplasmic reticulum of HeLa cells. The cells were irradiated with a diode laser (working at 670 nm; energy density of 4.5 J/cm(2 )and power density of 45 mW/cm(2)). The spectrofluorimetric analysis of the mitochondria showed changes in membrane potential. Cytoskeleton and endoplasmic reticulum showed basic alterations in distribution after PDT treatment, as an indicator of cellular death process.

Effect of GaInAIP (685 nm) radiation on lipopolyssacharide induced rat trachea hyperreactivity

O objetivo do presente estudo foi investigar o efeito do laser de baixa potência (LLLT) na hiper-reatividade da traquéia de ratos Wistar macho(RTHR) depois da administração de lipopolissacarídeo (LPS)

Using the laser-induced fluorescence spectroscopy in the differentiation between normal and neoplastichuman breast tissue.

This article reports results of the in vitro study for potential evaluation of the laser-induced fluorescence spectroscopy in the differentiation between normal and neoplastic human breast tissue. A coumarine dye laser pumped by nitrogen laser generated an excitation light centered at 458 nm. In order to collect the fluorescence signal was used an optical fiber catheter coupled to a spectrometer and CCD detector. Fluorescence spectra were recorded from normal and neoplastic (benign and malignant) human breast tissue, adding up 94 different areas. The discrimination between normal and neoplasm groups reach a sensitivity and specificity of 100%.

Comparison of the low level laser therapy effects on cultured human gingival fibroblasts proliferation using different irradiance and same fluence.

BACKGROUND AND OBJECTIVE: The low level laser therapy (LLLT) has been used in Dentistry to improve wound healing. In order to analyse the effect of LLLT on the in vitro proliferation of gingival fibroblasts we developed a primary culture of human gingival fibroblasts. STUDY DESIGN/MATERIALS AND METHODS: The cell line named LMF was grown in Dulbecco's Modified Eagle's medium (DME) with either 5% (nutritional deficit) or 10% fetal bovine serum (fbs). Laser irradiation was carried out with diode lasers with the following wavelengths: 670 nm (L1), 780 nm (L2), 692 nm (L3), and 786 nm (L4). The fluence was fixed in 2 J/cm(2). For growth analysis, control (not irradiated) and treated cultures (irradiated) were plated in 60 mm diameter culture dishes for 12 h before the irradiation. RESULTS: We found that cells cultured in nutritional deficit condition grown in medium supplemented by only 5% fbs presented a cell proliferation rate significantly smaller that cell grown in ideal culture conditions (10% fbs). However, when irradiated, cells in nutritional deficit presented cell growth similar or higher than that of control cells grown in ideal culture conditions. Using the same fluence, the infrared laser induced a higher cell proliferation than visible laser when the power outputs were different. However, lasers of equal power output presented similar effect on cell growth independently of their wavelengths. CONCLUSIONS: The LLLT acts by improving the in vitro fibroblast proliferation and a smaller laser exposure time results in higher proliferation.

Analysis of near-infrared Raman spectroscopy as a new technique for a transcutaneous non-invasive diagnosis of blood components.

Near-infrared Raman spectroscopy can be a new technique for physical evaluations, allowing the measurement of lactic acid concentrations, in blood or muscles, during the physical activity in a transcutaneous non-invasive way. Lactic acid accumulation in the human body is one of the factors that leads to fatigue and therefore it should be continually monitored during physical training. Our proposal is to use Raman spectroscopy to monitor the lactic acid present in an athlete without interrupting his exercise for sample collection. The experimental set-up for Raman spectroscopy comprised a near infrared laser at 830 nm, a Kaiser f/1.8 spectrometer and a liquid nitrogen cooled CCD detector. The radiation from the exciting laser is blocked in the collecting system by Kaiser holographic filters. A personal computer controls the entire system, saving and processing the Raman spectra. Experiments were undertaken to verify the presence of lactic acid in the Raman spectra of solutions of lactic acid in human serum and in blood from a Wistar rat. After these two experiments, another was developed in vivo in a Wistar rat, injecting intraperitoneally 1 ml of a 0.12 mol/l lactic acid aqueous solution. An optical fibre catheter touching the skin of the rat groin, over the ileac vein collected the Raman signal. The presence of lactic acid was detected inside a live organism, in a transcutaneous non-invasive way. The minimum lactic acid concentration that the equipment can detect was also studied. An experiment was undertaken for that purpose, in which the laser illuminated directly a quartz cuvette containing solutions with decreasing lactic acid concentrations up to values near to the physiological level in the human body. The results indicated that the technique can be suitable for the physical evaluation of athletes.

Development of catheters with low fiber background signals for Raman spectroscopic diagnosis applications.

Utilization of optical-fiber catheters can turn the Raman spectroscopy system into a powerful remote biomedical diagnostic probe. An in vivo (a qualitative and a quantitative) biochemical diagnosis of biotissues is possible by developing the Raman-fiber probes with a good flexibility and less background signals generated in the probes themselves. Considering the isotropic nature of Raman scattering, the amount of Raman signal guided through the fiber is expected to depend on the numerical aperture (NA) of the fiber. To study the dependence for catheter probes experimentally, various flexible probes (with small diameter fibers) with different combinations of numerical apertures and with different assembling materials (biocompatible) have been developed. The catheter probes have been characterized by collecting the near infrared excited Raman scattered light from cholesterol powder. The results demonstrate that the catheters with a combination of lower NA (0.12) fibers used for laser excitation and relatively higher NA (0.22) fibers for Raman signal collection will have lower background signals generated in the probes. Furthermore, the catheters with a black Teflon tubing cover and black epoxy resin adhesives were found to give better results.

Rapid multiexcitation fluorescence spectroscopy system for in vivo tissue diagnosis.

We have designed, fabricated, and tested a compact, transportable, excitation-emission spectrofluorimeter with optical-fiber light delivery and collection for use in rapid analysis of tissues in a clinical setting. This system provides up to eleven different excitation wavelengths, permitting collection of all the corresponding emission spectra in approximately 600 ms. It uses a N(2) laser that pumps a sequence of dyes placed in cuvettes on a rotating wheel. A white-light excitation source permits acquisition of the tissue's diffuse reflectance spectrum on each cycle. Return fluorescence and reflected light are dispersed by a small spectrograph and detected by a photodiode-array detector. The system can collect a single-shot spectrum from biological tissue with a signal-to-noise ratio in excess of 50:1.

Desenvolvimento de um sistema Raman multicanal operando no infravermelho para diagnóstico de tecidos biológicos / Development of the multichannel Raman system operating in infrared for biological tissue diagnostic techniques

Nós desenvolvemos uma das mais avançadas técnicas de diagnóstico de tecidos biológicos, a espectroscopia Raman multicanal. Utilizando este sistema, foi demonstrado que a espectroscopia Raman pode ser empregada para discriminar tecidos normais de anormais nas artérias humanas. Além do mais, foi demonstrado que espectros Raman de artérias coronárias humanas podem ser coletados rapidamente, em tempos da ordem de 10 ms, permitindo ser uso em ambiente clínico.

Abstract - We developed one of the most advanced bio-tissue diagnostic techniques, near infrared (NIR) multichannel Raman spectroscopy system. Utilizing such a system, it has been demonstrated that NIR Raman spectroscopy can be employed for discriminating between healthy and diseased tissues in human arteries. Further, it has been shown that NIR Raman spectra of human coronary arteries can be collected rapidly with collection times as small as 1 O ms that makes its clinicai use feasible

Espectrofluorímetro de multi-excitaçäo portátil para a rápida deteçäo de displasias / Spectrofluorimeter of portable multi-excitation for rapid detection of dysplasia

Neste trabalho é apresentado o projeto e desenvolvimento de um espectrofluorímetro para a obtenção de espectros de fluorescência e refletância difusa de tecidos biológicos em um tempo inferior a 1s. Para acessar a região da diagnose, o sistema utiliza um catéter a fibra óptica para excitação do tecido e captação da fluorescência emitida. O sistema é desenvolvido para aplicação em procedimentos clínicos in vivo, onde o tempo de realização do experimento é objetivo de extrema importância

Abstract- This work presents the project and development of a spectrofluorimeter in order to obtain the fluorescence spectra and diffuse reflectance from biological tissues with period of time below 1 s. The diagnose region is reached with an optical fiber catheter for tissue excitation and collection of the emitted fluorescence. This system is developed for in vivo clinicai applications, where duration of the experimental procedure is a very important parameter