The aim of this study was to evaluate the process of bone repair in rats submitted to low-level laser therapy using optical densitometry. A total of 45 rats which underwent femoral osteotomy were randomly distributed into three groups: control (group I) and laser-treated groups using wavelengths in the red (λ, 660-690 nm) and in the infrared (λ, 790-830 nm) spectra (group II and group III, respectively). The animals (five per group) were killed after 7, 14, and 21 days and the femurs were removed for optical densitometry analysis. Optical density showed a significant increase in the degree of mineralization (gray level) in both groups treated with the laser after 7 days. After 14 days, only the group treated with laser therapy in the infrared spectrum showed higher bone density. No differences were observed between groups after 21 days. Such results suggest the positive effect of low-level laser therapy in bone repair is time- and wavelength-dependent. In addition, our results have confirmed that optical densitometry technique can measure bone mineralization status.

Our results suggest that the anti-inflammatory therapy with low-power LED (880 nm) enhanced the tissue response in all groups. We can conclude that the LED was able to reduce signs of inflammation in collagenase-induced tendinitis in rats by reducing the number of inflammatory cells and decrease mRNA expression of cytokines.

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.

The study aimed to investigate physiological and psychological states prior to competition and prior to training in three different demanding activities. Eighteen canoe athletes, 18 street runners and 18 jiu-jitsu fighters were included in this study (n=54). The Competitive State Anxiety Inventory-2 (CSAI-2), salivary cortisol and heart rate variability (HRV) were measured at two time points (pre-training and pre-competition). Somatic anxiety (F1,42 = 15.29, p = 0.0003), HRV (F1,42 = 23.24, p < 0.0001) and salivary cortisol (F1,42 = 22.96, p < 0.0001) were significantly greater at the pre-competition measurement point than at the pre-training point, but without a main effect of the type of athlete on these variables. A main effect of the type of athlete was found on somatic anxiety (F2,42 = 6.58, p = 0.0033), cognitive anxiety (F2,42 = 10.69, p = 0.0002) and self-confidence (F2,42 = 5.42, p = 0.0080). Correlations between most CSAI-2 and physiological parameters were not significant (p > 0.05). In conclusion, the results indicated that both emotional indices and psychophysiological indices of stress are higher before competition than before training, with differences between emotional states between these sports. Although correlations between emotional states and psycho-physiological states before competition and before training were largely non-significant, these findings reinforce the importance of psychological monitoring of athletes in association with traditional physiological markers such as cortisol and HRV in sportive training programmes as complementary resources to improve both competition performance and the training routine.

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