The Contribution of Endogenous Modulatory Systems to TMS- and tDCS-Induced Analgesia: Evidence from PET Studies.

Chronic pain is an important public health issue. Moreover, its adequate management is still considered a major clinical problem, mainly due to its incredible complexity and still poorly understood pathophysiology. Recent scientific evidence coming from neuroimaging research, particularly functional magnetic resonance (fMRI) and positron emission tomography (PET) studies, indicates that chronic pain is associated with structural and functional changes in several brain structures that integrate antinociceptive pathways and endogenous modulatory systems. Furthermore, the last two decades have witnessed a huge increase in the number of studies evaluating the clinical effects of noninvasive neuromodulatory methods, especially transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), which have been proved to effectively modulate the cortical excitability, resulting in satisfactory analgesic effects with minimal adverse events. Nevertheless, the precise neuromechanisms whereby such methods provide pain control are still largely unexplored. Recent studies have brought valuable information regarding the recruitment of different modulatory systems and related neurotransmitters, including glutamate, dopamine, and endogenous opioids. However, the specific neurocircuits involved in the analgesia produced by those therapies have not been fully elucidated. This review focuses on the current literature correlating the clinical effects of noninvasive methods of brain stimulation to the changes in the activity of endogenous modulatory systems.

Efficacy of viscosupplementation with hyaluronic acid in temporomandibular disorders: A systematic review.

OBJECTIVE: To perform a systematic review of the viscosupplementation effectiveness with hyaluronic acid (HA) in the articular Temporomandibular Dysfunctions (TMDs) clinical management. METHOD: Electronic searches were performed in the following databases: MEDLINE (via PubMed), Scopus, Web of Science, Cochrane Library, EMBASE, LILACS, BBO, SIGLE (System for Information on Grey Literature in Europe), ClinicalTrials.gov, and the Brazilian Clinical Trials Registry (ReBec). Only randomized clinical trials that evaluated the intra-articular administration of HA or its derivatives in osteoarthritis and/or anterior displacement of the temporomandibular joint (TMJ) disc were included. The primary outcomes evaluated were patients' self-report of pain and/or discomfort in the TMJ. Each study was assessed for the risk of bias, using the Cochrane collaboration's risk of bias tool. RESULTS: A total of 640 studies were obtained in the electronic search. After the application of the eligibility criteria, manual search, and duplicate removal, 21 articles were included. Five articles classified their volunteers with internal derangements of the TMJ, in 4 articles the treatment was directed to participants with disc displacement with reduction and the other articles evaluated HA therapy in osteoarthritis. The protocols presented heterogeneity, varying in the form of application, associated or not with arthrocentesis, number of applications, molecular weight, dose and concentration. Nine studies presented high risk of bias. CONCLUSION: Due to the heterogeneity and methodological inconsistencies of the studies evaluated, it was not possible to establish the efficacy of HA in articular TMDs.

Radioactive seed migration after prostate brachytherapy with iodine-125 using loose seeds versus stranded seeds.

OBJECTIVES: To assess the incidence and clinical parameters that could influence migration of seeds in localized prostate cancer patients treated by stranded versus loose sources by Iodine-125 brachytherapy. MATERIALS AND METHODS: 100 patients were treated from January/1998 until December/2006. Age, PSA, clinical stage, Gleason, prostate volume, number of seeds, activity of radioactive seeds, and dosimetric parameters, such as V100, V150 and D90 were evaluated. RESULTS: Mean follow-up was 79 months (18 - 120. CI 95%: 72 - 85). Overall, 6 of 100 patients experienced seed migration. Seed migration was found in 4/50 (8%) patients using loose seeds and in 2/50 (4%) treated by stranded seeds. Mean value dosimetric parameters for stranded seeds were greater than those for loose seeds (V100(%): 88.7/82, D90(Gy): 149.2/140.3, D90(%): 104.2/93.8, V150 (%): 53.8/47, respectively). No significant difference in migration of seeds was detected between loose and stranded seeds considering age (p = 0.33), PSA (p = 0.391), prostate volume (p = 0.397), activity of radioactive seeds (p = 0.109), number of seeds (p = 0.338), V100 (p = 0.332), although significant differences were measured in the values of D90(% and Gy) (p = 0.022 and 0.011) and V150 (p = 0.023). CONCLUSIONS: Seed migration after brachytherapy might occur and it does affect post-implant dosimetry.

Radioactive seed migration after prostate brachytherapy with Iodine-125 using loose seeds versus stranded seeds

Objectives: To assess the incidence and clinical parameters that could influence migration of seeds in localized prostate cancer patients treated by stranded versus loose sources by Iodine-125 brachytherapy. Material and Methods: 100 patients were treated from January/1998 until December/2006. Age, PSA, clinical stage, Gleason, prostate volume, number of seeds, activity of radioactive seeds, and dosimetric parameters, such as V100, V150 and D90 were evaluated. Results: Mean follow-up was 79 months (18 - 120. CI 95 percent: 72 - 85). Overall, 6 of 100 patients experienced seed migration. Seed migration was found in 4/50 (8 percent) patients using loose seeds and in 2/50 (4 percent) treated by stranded seeds. Mean value dosimetric parameters for stranded seeds were greater than those for loose seeds (V100( percent): 88.7/82, D90(Gy): 149.2/140.3, D90( percent): 104.2/93.8, V150 ( percent): 53.8/47, respectively). No significant difference in migration of seeds was detected between loose and stranded seeds considering age (p = 0.33), PSA (p = 0.391), prostate volume (p = 0.397), activity of radioactive seeds (p = 0.109), number of seeds (p = 0.338), V100 (p = 0.332), although significant differences were measured in the values of D90( percent and Gy) (p = 0.022 and 0.011) and V150 (p = 0.023). Conclusions: Seed migration after brachytherapy might occur and it does affect post-implant dosimetry.