The efficacy of transcranial direct current stimulation and transcranial magnetic stimulation for chronic orofacial pain: A systematic review.

BACKGROUND: Transcranial Direct Current Stimulation (tDCS) and Transcranial Magnetic Stimulation (TMS) have been described as promising alternatives to treat different pain syndromes. This study evaluated the effects of TMS and tDCS in the treatment of chronic orofacial pain, through a systematic review. METHODS: An electronic search was performed in major databases: MEDLINE, Scopus, Web of Science, Cochrane, Embase, LILACS, BBO, Open Gray and CINAHL. The eligibility criteria comprised randomized clinical trials (RCTs) that applied TMS or tDCS to treat chronic orofacial pain. The variables analyzed were pain, functional limitation, quality of life, tolerance to treatment, somatosensory changes, and adverse effects. The risk of bias was assessed through the Cochrane Collaboration tool, and the certainty of evidence was evaluated through GRADE. The protocol was registered in the PROSPERO database (CRD42018090774). RESULTS: The electronic search resulted in 636 studies. Thereafter, the eligibility criteria were applied and the duplicates removed, resulting in eight RCTs (four TMS and four tDCS). The findings of these studies suggest that rTMS applied to the Motor cortex (M1), the dorsolateral prefrontal cortex (DLPFC) and the secondary somatosensory cortex (S2) provide adequate orofacial pain relief. Two studies reported significant pain improvement with tDCS applied over M1 while the other two failed to demonstrate significant effects compared to placebo. CONCLUSIONS: rTMS, applied to M1, DLPFC or S2, is a promising approach for the treatment of chronic orofacial pain. Moreover, tDCS targeting M1 seems to be also effective in chronic orofacial pain treatment. The included studies used a wide variety of therapeutic protocols. In addition, most of them used small sample sizes, with a high risk of biases in their methodologies, thus producing a low quality of evidence. The results indicate that further research should be carried out with caution and with better-standardized therapeutic protocols.

The relationship of previous dental trauma with new cases of dental trauma. A systematic review and meta-analysis.

BACKGROUND/AIMS: Traumatic dental injuries (TDI) are a public health concern with high prevalence and recurrence rate. The aim of this study was to perform a systematic review and meta-analysis to determine whether previous dental trauma is a predictive factor for new episodes of TDI (recurrence or first episodes). MATERIALS AND METHODS: Electronic searches were performed with no language or date restrictions. According to the PECOS strategy, cohort studies that investigated subjects with and without previous TDI, and its association with new TDI episodes, as primary or secondary outcomes, were included. Quality assessment and bias control were carried out according to Fowkes and Fulton guidelines. A meta-analysis was performed by sub-grouping studies into deciduous and permanent dentition, and the risk ratio (RR) was also calculated (P ≤ 0.05). The evidence was quality-tested using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. RESULTS: After titles and abstracts were examined, and full texts were read, five studies were included in this systematic review. Four studies had high methodological quality, and one presented a risk of bias on confounding factors. No association and a positive association were determined between previous history of TDI and new episodes of TDI in the primary (RR 1.26 [0.99, 1.62], P = 0.06) and in the permanent dentitions (RR 2.68 [1.20, 4.19], I2  = 37%, P < 0.00001), respectively. The pooled results demonstrated a positive association (P < 0.00001) between previous dental trauma and new episodes of TDI (RR 2.17 [1.20, 3.90], P = 0.01, I2  = 83%) with moderate evidence quality level. CONCLUSIONS: Individuals that have suffered previous TDI present a greater risk of suffering new episodes of TDI.

Anandamide reverses depressive-like behavior, neurochemical abnormalities and oxidative-stress parameters in streptozotocin-diabetic rats: Role of CB1 receptors.

The pathophysiology associated with increased prevalence of depression in diabetics is not completely understood, although studies have pointed the endocannabinoid system as a possible target. Then, we aimed to investigate the role of this system in the pathophysiology of depression associated with diabetes. For this, diabetic (DBT) male Wistar rats were intraperitoneally treated with cannabinoid CB1 (AM251, 1mg/kg) or CB2 (AM630, 1mg/kg) receptor antagonists followed by anandamide (AEA, 0.005mg/kg) and then submitted to the forced swimming test (FST). Oxidative stress parameters, CB1 receptor expression and serotonin (5-HT) and noradrenaline levels in the hippocampus (HIP) and prefrontal cortex (PFC) were also performed. It was observed that DBT animals presented a more pronounced depressive-like behavior and increase of CB1 receptor expression in the HIP. AEA treatment induced a significant improvement in the depressive-like behavior, which was reversed by the CB1 antagonist AM251, without affecting the hyperglycemia or weight gain. AEA was also able to restore the elevated CB1 expression and also to elevate the reduced level of 5-HT in the HIP from DBT animals. In addition, AEA restored the elevated noradrenaline levels in the PFC and induced a neuroprotective effect by restoring the decreased reduced glutathione and increased lipid hydroperoxides levels along with the decreased superoxide dismutase activity observed in HIP or PFC. Together, our data suggest that in depression associated with diabetes, the endocannabinoid anandamide has a potential to induce neuroadaptative changes able to improve the depressive-like response by its action as a CB1 receptor agonist.

Increased oxidative stress in prefrontal cortex and hippocampus is related to depressive-like behavior in streptozotocin-diabetic rats.

Depression is a common comorbid in diabetic patients. The pathophysiologic mechanisms that relate this comorbidity is not completely elucidated yet, although several lines of evidence point out that increased oxidative stress resulting from hyperglycemia may have a crucial role. Thus, the effect of prolonged treatment with insulin (INS), the antioxidant vitamin E (VIT E) or the antidepressant imipramine (IMI) was evaluated in animals submitted to forced swimming test. Oxidative stress parameters (lipid peroxidation product levels, reduced gluthatione levels and catalase and superoxide dismutase activities) were also evaluated in brain areas related to depression, prefrontal cortex (PFC) and hippocampus (HIP). Our data show that treatment of streptozotocin-induced diabetic (DBT) rats with INS (6 UI/day, s.c.) prevented the blood glucose increase, reduced the immobility time, an antidepressant-like behavior, and normalized the reduced weight gain. Although the VIT E treatment (300 mg/kg, p.o.) had not altered the blood glucose levels, this treatment was able to reduce the immobility time and to reestablish the reduced weight gain in DBT rats. Differently, treatment with IMI (15 mg/kg, i.p.) induced antidepressant-like behavior in normoglycemic besides DBT animals. While VIT E and IMI treatments restored only specific oxidative stress parameters, INS was able to prevent all changed parameters evaluated in both PFC and HIP from DBT animals. Therefore, our data provide further evidence of the importance of oxidative stress in PFC and HIP in the pathophysiology of depression related to diabetes.

Assessment of anthropometric indexes of children and adolescents with Down syndrome.

OBJECTIVE: To compare the agreement in the classification of the weight-for-age (W/A) and height-for-age (HA) indexes for children and adolescents with Down syndrome (DS) according to selected international reference distributions. METHODS: A cross-sectional study was carried out in children (2 to 9.9 years old) and adolescents (10 to 17.9 years old) with DS from cities in the state of Rio de Janeiro, Brazil, in 2005. The W/A and H/A indexes were classified according to the percentiles of two curves developed for individuals with DS and one distribution developed for healthy subjects. The cut-off limits applied for categorization were: below the 5th percentile (< P5) and above the 95th percentile (> 95). The weighted Kappa index was estimated to assess agreement between the classifications (p < 0.05). RESULTS: Information was obtained on 98 children and 40 adolescents. From 1.0 to 18.4% of the children were < P5 for W/A, and the agreement for this index was considered weak (Kappa = 0.16; 95%CI -0.03-0.34; p < 0.01); no agreement was observed between the H/A classifications. For adolescents, W/A < P5 varied from 2.5 to 5.0%; once more there was no agreement for this classification (Kappa = 0.16; 95%CI -0.15-0.48; p > 0.05). There was good agreement for the H/A index (Kappa = 1.00; 95%CI 0.23-1.00; p < 0.01). CONCLUSION: There was weak agreement between classifications of anthropometric indexes according to three different distributions. The data indicated that the construction of specific curves for individuals with DS would facilitate the identification of overweight, which is often observed among these patients.

Comparação entre distribuições de referência para a classificação do estado nutricional de crianças e adolescentes com síndrome de Down / Assessment of anthropometric indexes of children and adolescents with Down syndrome

OBJETIVO: Avaliar a concordância da categorização dos índices peso para idade (P/I) e estatura para idade (E/I) em indivíduos com síndrome de Down segundo diferentes curvas. MÉTODOS: Desenvolveu-se estudo transversal em crianças (2 a 9,9 anos de idade) e adolescentes (10 a 17,9 anos de idade) com síndrome de Down assistidos em instituições da região metropolitana do Rio de Janeiro. Os índices de P/I e E/I foram categorizados segundo os percentis de três curvas: duas para indivíduos com síndrome de Down e outra para indivíduos saudáveis. Os limites utilizados na categorização foram o percentil 5 (P5) e o percentil 95 (P95). Utilizou-se o Kappa ponderado na avaliação da concordância das classificações (significativo quando p < 0,05). RESULTADOS: Foram obtidas informações de 98 crianças e 40 adolescentes. Entre as crianças, o P/I < P5 variou de 1,0 a 18,4 por cento; a concordância para essa categorização foi considerada fraca (Kappa = 0,16; IC95 por cento -0,03-0,34; p < 0,01); para E/I, não foi observada concordância na classificação. Entre os adolescentes, a categorização do P/I < P5 variou de 2,5 a 5,0 por cento; a concordância para essa classificação foi fraca (Kappa = 0,16; IC95 por cento -0,15-0,48; p > 0,05); para E/I, a concordância foi boa (Kappa = 1,00; IC95 por cento 0,23-1,00; p < 0,01). CONCLUSÃO: A concordância entre as classificações dos índices P/I e E/I geradas por diferentes distribuições mostrou-se fraca. Os dados indicam que o desenvolvimento de curvas específicas para indivíduos com síndrome de Down seria útil para a identificação de distúrbios ponderais, como o excesso de peso, que é freqüentemente observado nesse grupo.

OBJECTIVE: To compare the agreement between classifications of children and adolescents with Down syndrome (DS) by weight for age (W/A) and height for age (H/A) indexes according to a selection of international reference curves. METHODS: A cross-sectional study was carried out of children (2 to 9.9 years old) and adolescents (10 to 17.9 years old) with DS from cities in the state of Rio de Janeiro, Brazil, in 2005. The W/A and H/A indexes were classified according to the percentiles of two curves developed for individuals with Down syndrome and one distribution developed for healthy subjects. The cut-off limits applied for categorization were: below the 5th percentile (< P5) and above the 95th percentile (> 95). The weighted Kappa index was estimated to assess agreement between the classifications (p < 0.05). RESULTS: Information was obtained on 98 children and 40 adolescents. From 1.0 to 18.4 percent of the children were < P5 for W/A and the agreement for this index was considered weak (Kappa = 0.16; 95 percentCI -0.03-0.34; p < 0.01) no agreement was observed between the H/A classifications. For adolescents, W/A < P5 varied from 2.5 to 5.0 percent; and once more there was no agreement for this classification (Kappa = 0.16; 95 percentCI -0.15-0.48; p > 0.05). There was good agreement for the H/A index (Kappa = 1.00; 95 percentCI 0.23-1.00; p < 0.01). CONCLUSION: There was weak agreement between classifications of anthropometric indexes according to three different distributions. The data indicate that the construction of specific curves for individuals with DS would facilitate the identification of overweight, which is often observed among these patients.

Fabrication, structural characterization, and applications of langmuir and langmuir-blodgett films of a poly(azo)urethane.

The synthesis of a poly(azo)urethane by fixing CO(2) in bis-epoxide followed by a polymerization reaction with an azodiamine is presented. Since isocyanate is not used in the process, it is termed "clean method" and the polymers obtained are named "NIPUs" (non-isocyanate polyurethanes). Langmuir films were formed at the air-water interface and were characterized by surface pressure vs mean molecular area per mer unit (Pi-A) isotherms. The Langmuir monolayers were further studied by running stability tests and cycles of compression/expansion (possible hysteresis) and by varying the compression speed of the monolayer formation, the subphase temperature, and the solvents used to prepare the spreading polymer solutions. The Langmuir-Blodgett (LB) technique was used to fabricate ultrathin films of a particular polymer (PAzoU). It is possible to grow homogeneous LB films of up to 15 layers as monitored using UV-vis absorption spectroscopy. Higher number of layers can be deposited when PAzoU is mixed with stearic acid, producing mixed LB films. Fourier transform infrared (FTIR) absorption spectroscopy and Raman scattering showed that the materials do not interact chemically in the mixed LB films. The atomic force microscopy (AFM) and micro-Raman technique (optical microscopy coupled to Raman spectrograph) revealed that mixed LB films present a phase separation distinguishable at micrometer or nanometer scale. Finally, mixed and neat LB films were successfully characterized using impedance spectroscopy at different temperatures, a property that may lead to future application as temperature sensors. Principal component analysis (PCA) was used to correlate the data.