Analysis of pain relief and functional recovery in patients with rotator cuff tendinopathy through therapeutic ultrasound and photobiomodulation therapy: a comparative study.

This study aimed to compare shoulder tendinopathy treatment with therapeutic ultrasound combined with LED photobiomodulation therapy using LED-infrared (850 nm) or LED-red (640 nm). The study assessed 75 patients, aged 45 to 70 years, distributed into five experimental groups (15 patients each): therapeutic ultrasound (US), infrared light irradiation (IR), visible red light irradiation (VR), infrared light and ultrasound combined (IR-US), and red light in conjunction with ultrasound (VR-US). The ultrasound parameters are 1 MHz, 0.5 W/cm2 (SATA), and 100 Hz repetition rate, applied for 4 min each session. LED irradiation protocols were as follows: 3 points, 7.5 J per point, IR-LED 750 mW, 10 s, VR-LED 250 mW, 30 s. LED irradiation is followed by ultrasound in the combined therapies. The efficiency of the five therapies was evaluated assessing 12 parameters: quality of life (Health Assessment Questionnaire, HAQ), pain intensity (Visual Analog Scale, VAS), articular amplitude of shoulder movement (flexion, extension, abduction, adduction, medial rotation, lateral rotation), muscle strength (abduction, lateral rotation), and electromyography (lateral rotation, abduction). Treatments comprised 12 sessions for 4 weeks. Intra-group analysis showed that the five therapies significantly improved the recovery of all parameters after treatment. Regarding the comparison of irradiated therapies and ultrasound, statistical analysis showed that IR-US was a better treatment than US for all 12 parameters. IR treatment exceeded US on 9 items, whereas that VR and VR-US therapies exceeded US in 7 and 10 parameters, respectively (p < 0.05). Because of that, IR-US shows to be the best treatment for rotator cuff tendinopathy. In conclusion, improvements in quality of life, pain intensity relief, shoulder amplitude motion, and muscle strength force obtained with ultrasound therapy are enhanced by adding infrared LED irradiation to ultrasound for patients suffering from rotator cuff tendinopathy. This study was registered with the Brazilian Registry of Clinical Trials (ReBEC) under Universal Trial Number (UTN) U1111-1219-3594 (2018/22/08).

Application of phototherapy for the healing of the navels of neonatal dairy calves.

The present work evaluated the effects of LED light irradiation on the healing of the navels of neonatal dairy calves. Fifty-seven neonatal calves were divided into two groups. Animals had their umbilical stumps immersed in 10% iodine tincture for 60 s, and this process was repeated every 24 h for three consecutive days. The 29 animals in the first group did not receive LED therapy. The 28 animals in the second group received LED light irradiation at 640 nm with 300 mW power, 46.8 J/cm2 energy density, 60 s irradiation time, and 0.385 cm2 spot size. The animals were irradiated at four points (46.8 J/cm2 per point) evenly distributed around the insertion site of the umbilical stump every 24 h for three consecutive days. Irradiation with LED light was applied before the umbilical stumps were immersed in the iodine solution. The time after birth at which the umbilical stump fell off of each calf was noted. The umbilical stumps of all animals fell off by the 25th day of age. After the umbilical stump fell off, the healing of the remnant wound was followed up to the 30th day after birth. The area of the wound was measured on the 15th, 20th, and 25th day after birth using digital photographs and computer-assisted area measurements. A two-tailed unpaired t test was applied to analyze the falling off the umbilical stump, whereas a Kruskal-Wallis one-way ANOVA test with a Dunn's multiple comparison test was used for the wound size evolution. GraphPad Prisma 5.0® and GraphPad StatMate 2.00® were used for the statistical analysis. The results revealed that phototherapy hastened the falling off the umbilical stump, accelerated navel healing, and reduced the mortality rate in newborn calves. Therefore, this study introduced a preventive and adjuvant after birth treatment that proved to be effective in reducing the incidences of omphalitis and newborn mortality.

Analysis of experimental tendinitis in rats treated with laser and platelet-rich plasma therapies by Raman spectroscopy and histometry.

The objective of this controlled experimental study was to analyze the changes in the Achilles tendons of rats with experimentally induced tendinitis after treatment with platelet-rich plasma (PRP) and/or laser therapies by histometry to quantify fibroblasts and by Raman spectroscopy to determine the biochemical concentration of collagen types I and III. Fifty-four male Wistar rats were divided into six treatment groups: control (G1); PRP only (G2); irradiation with 660 nm laser (G3); irradiation with 830 nm laser (G4); PRP plus 660 nm laser irradiation (G5); and PRP plus 830 nm laser irradiation (G6). Injuries (partial tenotomy) were inflicted in the middle third of the Achilles tendon, with PRP added prior to suture in the appropriate experimental groups. A diode laser (model Laser Flash® III, DMC Equipamentos Ltda, São Carlos, SP, Brazil) that can be operated in two wavelengths 660 and 830 nm was used for irradiation treatments. The irradiation protocol was energy density of 70 J/cm², 20 s irradiation time, and 0.028 cm² spot area, per point in three points in the injured. The histometry was made in micrographical images of the H&E stained sections and evaluated by ImageJ (version 1.46r)®. Raman spectra were collected using a dispersive spectrometer at 830 nm excitation, 200 mW power, and 10 s integration time (P-1 Raman system, Lambda Solutions, Inc. MA, USA). The relative amount of type I collagen was significantly greater in the PRP plus 830 nm laser irradiation group (468 ± 188) than in the control (147 ± 137), 630 nm laser only (191 ± 117), and 830 nm laser only (196 ± 106) groups (p < 0.01), while the quantity of type III collagen was significantly greater in the PRP-only group compared to both irradiated groups without PRP (p < 0.05). Treatment with PRP combined with irradiation at 830 nm resulted in a larger number of fibroblasts and increased concentration of type I collagen, thus accelerating the healing of the injured tendon.

Low intensity laser and LED therapies associated with lateral decubitus position and flexion exercises of the lower limbs in patients with lumbar disk herniation: clinical randomized trial.

UNLABELLED: The objective of this study is to evaluate the effectiveness of laser and LED therapies, associated with lateral decubitus position and flexion exercises of the lower limbs in patients with lumbar disk herniation (LDH). It is a randomized blinded clinical trial. Fifty-four subjects with LDH L4-L5 and L5-S1 were selected and randomly allocated into groups: laser 904 nm, placebo, and LED 945 nm. The numbers of subjects for each group that completed the treatment were 18, 13, and 18, respectively. Twelve points over the lumbar spine region (L2 to S1) and eight points on the injured thigh in the path of the lumbar roots L5 and S1 were irradiated. Irradiation parameters for each point were as follows: laser wavelength 904 ± 10 nm, average power 0.038 ± 20 % W, irradiated area 0.16 cm(2), energy per point 4 J, and treatment time per point 104 s; LED wavelength 945 ± 15 nm, power 0.1 W, irradiated area 1.0cm(2), energy per point 4 J, and treatment time per point 40 s. Lateral decubitus opposite to the side of the radicular was the standard position for all patients. After phototherapy and laser placebo sessions, the subjects performed sequences of flexion exercises of the lower limbs (ten per session) for 15 daily sessions. VARIABLES STUDIED: pain intensity assessed by visual analog scale (VAS), degree of flexion of the affected hip measured by the universal goniometer and functional capacity assessed by the Oswestry Disability Index. The three groups had statistically significant improvement in lumbar and radicular pain, in hip mobility, and in the functional disability index (p ≤ 0.001). There was a statistically significant difference (p = 0.024) in radicular pain between the groups, gait claudication and Oswestry Disability Index. We can conclude that in the treatment of L4-L5 and L5-S1 LDH with radiculopathy, LED, associated with lateral decubitus position and flexion exercises of the lower limbs, showed better therapeutic performance for radicular pain, gait claudication, and functional disability.

Effect of light-emitting diode (ʎ 627 nm and 945 nm ʎ) treatment on first intention healing: immunohistochemical analysis.

Collagen I is not only responsible for maintaining the integrity of most tissues due to its mechanical properties, but also for its active participation in the functionality of tissues because of its interaction with cells present in the extracellular matrix. The synthesis of collagen begins with tissue injury and remains until the end of the healing process. The use of non-coherent light for healing processes is still understudied. This procedure stands out as a biostimulation method for tissue repair, which increases local circulation, cell proliferation, and collagen synthesis. This study sought to quantify collagen I in the healing process after the treatment of wounds with the light-emitting diode (LED) treatment. The histologic analysis with tissue samples stained with picrosirius red showed a statistical difference between the positive controls, LED 627 and LED 945 nm groups; the group treated with LED 627 nm showed a predominance of mature collagen. The immunohistochemical analysis showed a statistically significant high concentration of collagen I in the LED 945 nm group. The irradiation of wounds with the higher wavelength (945 nm) used in the study produced the best activity of collagen I formation in experimental model.

Effects of feedback on activation of the quadriceps during weight-bearing tasks of the Wii.

[Purpose] This investigation evaluated the effect of real-time feedback on electrical activation of the quadriceps during 3 weight-bearing tasks of the Wii Fit Plus(®). [Subjects] Thirty male healthy volunteers were recruited. [Methods] Activation of the vastus medialis, vastus lateralis, and rectus femoris muscles was recorded during virtual lunge, single leg extension, and single leg reach exercises. Each exercise was performed twice in 3 randomized experimental conditions (with visual feedback, with auditory feedback, and with no feedback). The normalized electromyographic data (using maximum voluntary isometric contraction) were analyzed using repeated measures analysis of variance and Tukey's test. [Results] No significant difference was found in the muscles among the feedback conditions during the 3 exercises. However, the variation in the muscle activity of the vastus medialis and vastus lateralis (18.23-29.20% of maximum voluntary isometric contraction) was higher (47-62%) than that in the rectus femoris (7.35-12.98% of maximum voluntary isometric contraction). [Conclusion] Real-time feedback did not alter quadriceps activation during the Wii tasks. Additionally, these games showed electromyographic activation levels similar to those for the same tasks outside the virtual environment. The Wii weight-bearing tasks could therefore constitute a physical activity program but without the additional benefit of feedback.

Raman spectroscopy detection of molecular changes associated with two experimental models of osteoarthritis in rats.

The aim of the present study was to evaluate the feasibility of applying Raman spectroscopy in probing the molecular changes in terms of collagen deposition and tissue remodeling associated with two well-established experimental models of osteoarthritis (OA) in knee of rats. In order to evaluate alterations in the articular surface area, the menisci-covered tibial region was assessed into three groups as follows: control (joint preserved) and two models of experimental knee OA: collagenase-induced model (n = 8) and treadmill exercise-induced model (n = 8). Each group was examined for molecular changes using spectral parameters related to cartilage, subchondral bone, and bone tissues. A significant increase of Raman ratios related to mineralization and tissue remodeling was found (p < 0.05), suggesting that both models were successful for inducing OA in rats. The significantly lower phenylalanine content and higher crystallinity in the treadmill exercise-induced model of OA than collagenase-induced model of OA (p < 0.05) indicated that the OA pathogenesis was model-dependent. Thus, this work suggests that the Raman spectroscopy technique has potential for the diagnosis and detection of cartilage damage and monitoring of subchondral bone and bone in OA pathogenesis at the molecular level.

Low-level light-emitting diode therapy increases mRNA expressions of IL-10 and type I and III collagens on Achilles tendinitis in rats.

The present study investigated the effects of low-level light-emitting diode (LED) therapy (880 ± 10 nm) on interleukin (IL)-10 and type I and III collagen in an experimental model of Achilles tendinitis. Thirty male Wistar rats were separated into six groups (n = 5), three groups in the experimental period of 7 days, control group, tendinitis-induced group, and LED therapy group, and three groups in the experimental period of 14 days, tendinitis group, LED therapy group, and LED group with the therapy starting at the 7th day after tendinitis induction (LEDT delay). Tendinitis was induced in the right Achilles tendon using an intratendinous injection of 100 µL of collagenase. The LED parameters were: optical power of 22 mW, spot area size of 0.5 cm(2), and irradiation time of 170 s, corresponding to 7.5 J/cm(2) of energy density. The therapy was initiated 12 h after the tendinitis induction, with a 48-h interval between irradiations. The IL-10 and type I and III collagen mRNA expression were evaluated by real-time polymerase chain reaction at the 7th and 14th days after tendinitis induction. The results showed that LED irradiation increased IL-10 (p < 0.001) in treated group on 7-day experimental period and increased type I and III collagen mRNA expression in both treated groups of 7- and 14-day experimental periods (p < 0.05), except by type I collagen mRNA expression in LEDT delay group. LED (880 nm) was effective in increasing mRNA expression of IL-10 and type I and III collagen. Therefore, LED therapy may have potentially therapeutic effects on Achilles tendon injuries.

Low-level laser therapy combined with platelet-rich plasma on the healing calcaneal tendon: a histological study in a rat model.

The objective of this study was to investigate the effects of low-level laser therapy (LLLT) treatment alone (λ = 660 nm and λ = 830 nm) or associated with platelet-rich plasma (PRP). We used 54 male rats divided into six groups, with nine animals each: group 1, partial tenotomy; group 2 (GII), PRP; group 3 (GIII): λ660 nm; group 4 (GIV), λ830 nm; group 5 (GV), PRP + λ660 nm; and group 6 (GVI), PRP + λ830 nm. The protocol used was power density 0.35 W/cm(2), energy 0.2 J, energy density 7.0 J/cm(2), time 20 s per irradiated point, and number of points 3. Animals in groups GII, GV, and GVI received treatment with PRP, consisting of a single dose of 0.2 mL directly into the surgical site, on top of the tenotomy. Animals were killed on the 13th day post-tenotomy and their tendons were surgically removed for a quantitative analysis using polarization microscopy. The percentages of collagen fibers of types I and III were expressed as mean ± SD. Higher values of collagen fibers type I were obtained for groups GV and GVI when compared with all other groups (p < 0.05), whereas groups GIII and GIV showed no significant difference between them (p > 0.05). For collagen type III, a significant difference was observed between GII and all other groups (p < 0.5), but no significant difference was found between GIII and GIV and between GV and GVI. Results showed that the deposition of collagen type I was higher when treatment with PRP and LLLT was combined, suggesting a faster regeneration of the tendon.

Cardiopulmonary and hematological effects of infrared LED photobiomodulation in the treatment of SARS-COV2.

BACKGROUND: COVID-19 disease is caused by SARS-CoV-2 which can trigger acute respiratory syndrome, which presents with dense alveolar and interstitial infiltrates and pulmonary edema, causing severe hypoxemia and significant alteration to pulmonary mechanics with reduced pulmonary compliance. The photobiomodulation technique alters cellular and molecular metabolism, showing promising results regarding the reduction of acute pulmonary inflammation. OBJECTIVE: To compare the photomodulation technique using near-infrared LED to conventional respiratory physiotherapy treatment in patients with COVID-19 in reversing acute conditions, reducing hospitalization time, and decreasing the need for oxygen therapy. METHODOLOGY: The cohort was comprised of 30 patients undergoing COVID-19 treatment who were divided and allocated into two equal groups randomly: the LED group (LED), treated with infrared LED at 940 nm and conventional therapy, and the control group (CON), who received conventional treatment (antibiotic therapy for preventing superimposed bacterial infections, and physiotherapy) with LED irradiation off. Phototherapy used a vest with an array of 300 LEDs (940 nm) mounted on a 36 cm × 58 cm area and positioned in the patient's anterior thoracic and abdominal regions. The total power was 6 W, with 15 min irradiation time. Cardiopulmonary functions and blood count were monitored before and after treatment. The patients were treated daily for 7 days. Statistical analysis was conducted using a two-tailed unpaired Student's t-test at a significance level of α = 0.05. RESULTS: Post-treatment, the LED group showed a reduction in hospital discharge time and a statistically significant improvement for the following cardiopulmonary functions: Partial Oxygen Saturation, Tidal Volume, Maximum Inspiratory, and Expiratory Pressures, Respiratory Frequency, Heart Rate, and Systolic Blood Pressure (p < 0.05). Regarding blood count, it was observed that post-treatment, the LED group presented with significant differences in the count of leukocytes, neutrophils, and lymphocytes. CONCLUSION: Photobiomodulation therapy can be used as a complement to conventional treatment of COVID-19, promoting the improvement of cardiopulmonary functions, and minimization of respiratory symptoms.

Systemic Effects of Photobiomodulation on Blood Components in the Treatment of Community-Acquired Pneumonia.

Background: The analysis of the complete blood count (CBC) of patients with community-acquired pneumonia (CAP) is an essential practice both for diagnosing the disease and for evaluating the patient's clinical evolution. It is proposed in the present study to analyze the hematological alterations resulting from photobiostimulation using near-infrared light-emitting diodes (LEDs) in patients with CAP. Methods: This was a clinical, prospective, blinded, and descriptive longitudinal study that involved 21 patients undergoing CAP treatment who were divided into two groups: LED, 11 patients who were treated with infrared LED and conventional treatment; and CON (control), 10 patients who received only conventional treatment (antibiotic therapy and physiotherapy). Physiotherapy was applied before LED irradiation in the LED group. The patients' CBCs were obtained before and after treatment, and erythrocyte counts, hemoglobin and hematocrit concentrations, and leukocyte and platelet counts were assessed. The phototherapy was performed with a vest with an array of 300 LEDs (940 nm) mounted on an area of 36 × 58 cm and positioned in the patient's anterior thoracic and abdominal regions. The total power was 6 W, with 15 min of irradiation time. The patients were treated daily for seven consecutive days. Statistical analyses of the intra- and intergroups of CBC data were done using Student's t-test and one-way ANOVA (analysis of variance), respectively, both at the significance level of α = 0.05. Results: There was a statistically significant recovery difference after treatment in the LED group compared with the CON group for erythrocytes, hemoglobin, leukocytes, segmented and band neutrophils, lymphocytes, and monocytes (p < 0.05). The greatest differences between the LED and CON groups were lymphocyte count reduction (60% vs. 16%), erythrocyte increase (86% vs. 35%), and leukocyte reduction (28% vs. 15%). Conclusions: The hematologic components of CAP patients recovered their normal values faster with conventional treatment associated with infrared LED therapy, thus indicating greater treatment efficiency when compared with the conventional therapy. This study was registered with the Brazilian Registry of Clinical Trials (ReBeC) under Universal Trial Number (UTN) U1111-1229-1296 (2019/06/05).

Antiedematous Effect Promoted by Occlusion of Legs with Compressive Socks Containing Infrared-Emitting Ceramic Particulates.

Background: Published literature reports significant improvements in pathological conditions, such as pain, blood dyscrasias, and cellulite, after using topical occlusive accessories containing particulate ceramic materials. Objective: In this study, we investigated whether the use of a topical occluding garment made with synthetic fibers embedded with powdered ceramic materials could be beneficial to patients suffering from edema of lower limb extremities. Materials and methods: The cohort comprised 30 volunteers of both genders who were divided into two study groups. The bioceramic (BC) group wore compressive socks made of fabrics with embedded ceramic powder for 8 h a day for 28 days. The placebo group wore compressive socks of the same material without ceramic powder. The efficacy of the treatment was quantified through weekly plethysmographic measurements. In addition, pain relief was evaluated through a visual analog scale (VAS). Results: Data showed a statistically significant reduction in the edema volume for the BC group compared with the placebo group: 78.9 ± 10.7 mL versus 41.3 ± 5.6 mL, p = 0.003. Further, there was also greater pain relief for the BC group when compared with the placebo group, with a pain decrease of 7.0 ± 0.2 U versus 3.3 ± 0.2 U, respectively, on the VAS from 0 to 10 (p = 0.024). Conclusions: The topical occlusive therapy with compressive socks containing infrared-emitting ceramic particulate in its fabrics showed that they were more beneficial than the placebo garment in the treatment of edema of the inferior member extremities as well as in relief of associated pain.

Effect of low-level laser therapy in the inflammatory response induced by Bothrops jararacussu snake venom.

This article reports the effect of low-level laser therapy (LLLT) on the edema formation and leukocyte influx caused by Bothrops jararacussu snake venom as an alternative treatment for Bothrops snakebites. The inflammatory reaction was induced by injection of 0.6 mg/kg of B. jararacussu venom, in gastrocnemius muscle. Cell influx and edema were evaluated at 3 or 24h after venom injection. Mice were irradiated at the site of injury by a low-level laser (685 nm) with a dose of 4.2J/cm(2). A therapy that combines LLLT and antivenom was also studied. B. jararacussu venom caused a significant edema formation 3 and 24h after its injection, and a prominent leukocyte infiltrate composed predominantly of neutrophils at 24h after venom inoculation. LLLT significantly reduced edema formation by 53% and 64% at 3 and 24h, respectively, and resulted in a reduction of neutrophils accumulation (P<0.05). The combined therapy showed to be more efficient than each therapy acting separately. In conclusion, LLLT significantly reduced the edema and leukocyte influx into the envenomed muscle, suggesting that LLLT should be considered as a potentially therapeutic approach for the treatment of the local effects of Bothrops species.

Cytokine mRNA expression is decreased in the subplantar muscle of rat paw subjected to carrageenan-induced inflammation after low-level laser therapy.

OBJECTIVE: The objective of this work was to investigate the anti-inflammatory effects of low-level laser therapy, applied at different wavelengths (660 and 684 nm), on cytokine mRNA expression after carrageenan-induced acute inflammation in rat paw. BACKGROUND DATA: Low-level laser therapy (LLLT) has been observed to reduce pain in inflammatory disorders. However, little is known about the mechanisms behind this effect or whether it is wavelength-specific. MATERIALS AND METHODS: The test sample consisted of 32 rats divided into four groups: A(1) (control-saline), A(2) (carrageenan-only), A(3) (carrageenan + 660 nm laser therapy), and A(4) (carrageenan + 684 nm laser therapy). The animals from groups A(3) and A(4) were irradiated 1 h after induction of inflammation by carrageenan injection. Continuous-wave red lasers with wavelengths of 660 and 684 nm and dose of 7.5 J/cm(2) were used. RESULTS: Both the 660 nm and 684 nm laser groups had 30%-40% lower mRNA expression for cytokines TNF-alpha, IL-1beta, and IL-6 in the paw muscle tissue than the carrageenan-only control group. Cytokine measurements were made 3 h after laser irradiation of the paw muscle, and all cytokine differences between the carrageenan-only control group and the LLLT groups were statistically significant (p < 0.001). CONCLUSIONS: LLLT at the 660-nm and 684-nm wavelengths administered to inflamed rat paw tissue at a dose of 7.5 J/cm(2) reduce cytokine mRNA expression levels within 3 h in the laser-irradiated tissue.

A Study on the Macroscopic Morphometry of the Lesion Area on Diabetic Ulcers in Humans Treated with Photodynamic Therapy Using Two Methods of Measurement.

BACKGROUND: Diabetes Mellitus is a chronic disease that can lead to lower-limb ulceration. The photodynamic therapy (PDT) is based on light interaction with a photosensitizer capable to promote bacterial death and acceleration of wound healing. OBJECTIVE: This study aims to accomplish a macroscopic morphometry evaluation on diabetic ulcer area in humans that were under PDT. MATERIALS AND METHODS: A clinical study was conducted by convenience sample, experimental, controlled, and blinded, composed of 12 patients of both sexes with diabetic ulcers in lower limbs that were divided into two groups, control (n = 6) and PDT (n = 6). They were all treated with collagenase/chloramphenicol during the experimental period, in which six of them had received PDT with Methylene Blue dye (0.01%) associated with laser therapy (660 nm, 30 mW, 8 sec, 6 J/cm2, beam area of 0.04 mm2), three times per week, totaling 10 sessions. Ulcer areas were analyzed by their nominal area and photographed for analysis through the ImageJ® software. Then, the Ulcer Healing Index and the wound area reduction were calculated for both groups. RESULTS: Data from the UHI and wound area reduction parameters show that there is a statistically significant difference (p < 0.05) between the control group and PDT group, with the PDT group showing a greater reduction of the diabetic ulcer area than the control group. In the ImageJ software area analysis, both patient groups presented significant differences (p < 0.05) between pre and post-treatment in relation to lesion reduction area, the PDT being better. CONCLUSIONS: Results show that PDT accelerates the closure of ulcer wounds and to evaluate the wound area, different measurement methods can be used to follow-up the tissue repair process.

Use of photodynamic therapy in the treatment of bovine subclinical mastitis.

BACKGROUND: Bovine mastitis is a disease that causes a severe drawback in dairy production. Conventional treatments with antibiotic could leave antibiotic residues in the milk. The aim of this study was to evaluate the effect of photodynamic therapy in the treatment of bovine subclinical mastitis to develop an in vivo therapeutic protocol that could be used in routine farm practice, favoring the early return to production. METHODS: Forty cows with subclinical mastitis (n = 40) were divided into 4 groups (control, photodynamic therapy - PDT, light irradiation - LED, and photosensitizer - PS). Control group received no treatment, PDT group received application of 1.0 mL of 2.5% toluidine blue photosensitizer followed by LED irradiation at λ = 635 nm, the LED group was treated with LED irradiation alone, and the PS group received only 2.5% toluidine blue dye. LED irradiation was applied to the mammary gland by means of an acrylic light guide coupled to the LED equipment. The PDT and LED groups were irradiated with 200 J/cm2 at three different positions inside the mammary gland. Milk samples were collected at 0 h, 12 h, 24 h after treatment for microbial identification and total bacterial count. RESULTS: The treatment of the PDT group showed significant difference p < 0.05, characterizing the efficiency of this technique with the reduction of the microorganisms Streptococcus dysgalactiae and coagulase-negative Staphylococcus. CONCLUSION: Photodynamic therapy was effective when applied in vivo for subclinical bovine mastitis. There was no need to separate the animal from production.

Identification of calcifications in cardiac valves by near infrared Raman spectroscopy.

OBJECTIVE: The objective of this work was to detect calcification in cardiac valves using near infrared Raman spectroscopy (NIRS). A Ti:sapphire laser pumped by an argon-ion laser operating at a wavelength of 830 nm was used for excitation of the valve samples, and Raman emission was detected by an optical spectrometer with a liquid nitrogen-cooled CCD detector. BACKGROUND: Cardiac valves are subjected to highly repetitive mechanical stresses, due to their over 40 million cardiac cycles per year. These structures may suffer cumulative lesions, complicated by the deposition of calcium phosphate, which can lead to clinically significant diseases. NIRS can provide important information about biological tissue composition and has been used for diagnosis of some types of human pathology. METHODS: Samples of normal and pathologic tissues 5 mm in size were analyzed. RESULTS: It was observed that the Raman spectrum of calcified cardiac valves presented different behavior when compared with normal valves. Differences were observed at the intensity of 960, 1,260, 1,452, and 1,660 cm(1) peaks. CONCLUSIONS: These results suggest that this technique could be used to detect calcium phosphate mineral deposition in cardiac valves.

Use of near-infrared Raman spectroscopy for identification of atherosclerotic plaques in the carotid artery.

OBJECTIVES: The aim of this work was to identify the presence of atherosclerotic plaque in the human carotid artery using near infrared Raman spectroscopy. BACKGROUND DATA: Atherosclerosis is the most common and serious pathology of the cardiovascular system. Raman spectroscopy is an analytical tool that can be used to gather information about both the morphology and chemical composition of tissues. METHODS: A Ti:sapphire laser operating at the near-infrared wavelength of 830 nm pumped by an argon laser was used for excitation of the samples, and the Raman scattering was detected by an optical spectrometer with a liquid-nitrogen-cooled CCD detector. Carotid artery samples were classified into five groups: normal, intimal thickening, fatty plaque, fibrous-fatty plaque, and fibrous-calcified plaque. RESULTS: It was observed that the Raman spectrum of atheromatous plaque was different that that of normal tissue. The spectra of atheromatous plaques had bands due to the presence of cholesterol and its esters, with major bands at 1439 and 1663 cm(1), respectively. In normal tissues a peak related to C-H bending appears at 1451 cm(1). Calcified atheromatous plaques had primary bands at 961 and 1071 cm(1), which were due to the presence of phosphate and carbonate in the accumulated calcium. Peaks were seen at 1451 and 1655 cm(1) in the non-atherosclerotic tissue, which were shifted to 1439 and 1663 cm(1) in the atherosclerotic plaque. CONCLUSIONS: Our results indicate that this technique could be used to detect the presence of atherosclerotic plaques in carotid arterial tissue.

Comparison between wound healing in induced diabetic and nondiabetic rats after low-level laser therapy.

OBJECTIVE: The aim of this work was to compare the effect of low-level laser therapy (LLLT) on the wound healing process in nondiabetic and diabetic rats. BACKGROUND DATA: Among the clinical symptoms caused by diabetes mellitus, a delay in wound healing is a potential risk for patients. It is suggested that LLLT can improve wound healing. METHODS: The tissue used for this study was extracted from animals suffering from diabetes, which was induced by Streptozotocin, and from nondiabetic rats. Animals were assembled into two groups of 25 rats each (treated and control) and further subdivided into two groups: diabetic (n = 15) and nondiabetic (n = 10). A full-thickness skin wound was made on the dorsum area, with a round 8-mm holepunch. The treated group was irradiated by a HeNe laser at 632.8 nm, with the following parameters: 15 mW, exposition time of 17 sec, 0.025 cm2 irradiated area, and energy density of 10 J/cm2. Square full-thickness skin samples (18 mm each side, including both injured and noninjured tissues) were obtained at 4, 7, and 15 days after surgery and analyzed by qualitative and quantitative histological methods. RESULTS: Quantitative histopathological analysis confirmed the results of the qualitative analysis through histological microscope slides. When comparing tissue components (inflammatory cells, vessels and fibroblast/area), we found that treated animals had a less intense inflammatory process than controls. CONCLUSION: Results obtained by both qualitative and quantitative analyses suggested that irradiation of rats with HeNe (632.8 nm), at the tested dose, promoted efficient wound healing in both nondiabetic and diabetic rats as, compared to the control group.

Flexural strength of pure Ti, Ni-Cr and Co-Cr alloys submitted to Nd:YAG laser or TIG welding.

Welding of metals and alloys is important to Dentistry for fabrication of dental prostheses. Several methods of soldering metals and alloys are currently used. The purpose of this study was to assess, using the flexural strength testing, the efficacy of two processes Nd:YAG laser and TIG (tungsten inert gas) for welding of pure Ti, Co-Cr and Ni-Cr alloys. Sixty cylindrical specimens were prepared (20 of each material), bisected and welded using different techniques. Four groups were formed (n=15). I: Nd:YAG laser welding; II- Nd:YAG laser welding using a filling material; III- TIG welding and IV (control): no welding (intact specimens). The specimens were tested in flexural strength and the results were analyzed statistically by one-way ANOVA. There was significant differences (p<0.001) among the non-welded materials, the Co-Cr alloy being the most resistant to deflection. Comparing the welding processes, significant differences (p<0.001) where found between TIG and laser welding and also between laser alone and laser plus filling material. In conclusion, TIG welding yielded higher flexural strength means than Nd:YAG laser welding for the tested Ti, Co-Cr and Ni-Cr alloys.