Fabiana Carvalho

Motor Cortex Excitability and BDNF Levels in Chronic Musculoskeletal Pain According to Structural Pathology.

The central sensitization syndrome (CSS) encompasses disorders with overlapping symptoms in a structural pathology spectrum ranging from persistent nociception [e.g., osteoarthritis (OA)] to an absence of tissue injuries such as the one presented in fibromyalgia (FM) and myofascial pain syndrome (MPS). First, we hypothesized that these syndromes present differences in their cortical excitability parameters assessed by transcranial magnetic stimulation (TMS), namely motor evoked potential (MEP), cortical silent period (CSP), short intracortical inhibition (SICI) and short intracortical facilitation (SICF). Second, considering that the presence of tissue injury could be detected by serum neurotrophins, we hypothesized that the spectrum of structural pathology (i.e., from persistent nociception like in OA, to the absence of tissue injury like in FM and MPS), could be detected by differential efficiency of their descending pain inhibitory system, as assessed by the conditioned pain modulation (CPM) paradigm. Third, we explored whether brain-derived neurotrophic factor (BDNF) had an influence on the relationship between motor cortex excitability and structural pathology. This cross-sectional study pooled baseline data from three randomized clinical trials. We included females (n = 114), aged 19–65 years old with disability by chronic pain syndromes (CPS): FM (n = 19), MPS (n = 54), OA (n = 27) and healthy subjects (n = 14). We assessed the serum BDNF, the motor cortex excitability by parameters the TMS measures and the change on numerical pain scale [NPS (0–10)] during CPM-task. The adjusted mean (SD) on the SICI observed in the absence of tissue injury was 56.36% lower than with persistent nociceptive input [0.31(0.18) vs. 0.55 (0.32)], respectively. The BDNF was inversely correlated with the SICI and with the change on NPS (0–10)during CPM-task. These findings suggest greater disinhibition in the motor cortex and the descending pain inhibitory system in FM and MPS than in OA and healthy subjects. Likewise, the inter-hemispheric disinhibition as well as the dysfunction in the descending pain modulatory system is higher in chronic pain without tissue injury compared to a structural lesion. In addition, they suggest that a greater level of serum BDNF may be involved in the processes that mediate the disinhibition of motor cortex excitability, as well as the function of descending inhibitory pain modulation system, independently of the physiopathology mechanism of musculoskeletal pain syndromes.

Effects of acupuncture on the symptoms of anxiety and depression caused by premenstrual dysphoric disorder

Objective The objective of this investigation was to evaluate the effects of acupuncture and sham acupuncture on the symptoms of anxiety and depression brought on by premenstrual dysphoric disorder (PMDD). Methods In a single-blind randomised clinical trial, 30 volunteers with PMDD were assigned alternately to group 1 (acupuncture) or group 2 (sham acupuncture), and completed an evaluation of symptoms of anxiety and depression using the Hamilton Anxiety (HAM-A) and Hamilton Depression (HAM-D) Rating Scales. The procedure was performed twice a week for two menstrual cycles, for a total of 16 attendances for each participant. Results Before the intervention the mean HAM-A and HAM-D scores did not differ between groups. Following the intervention symptoms of anxiety and depression were reduced in both groups; however, the improvement was significant in group 1 compared to group 2, as shown by a mean reduction in HAM-A scores of 58.9% in group 1 and 21.2% in group 2 (p<0.001). The reduction in the mean HAM-D scores was 52.0% in group 1 and 19.6% in group 2, resulting in a significant difference (p=0.012). Conclusions The results suggest that acupuncture could be another treatment option for PMDD patients.

Estudo das partículas totais em suspensão e metais associados em áreas urbanas

This work aims at the study of the air quality determination regarding the total suspended particles (TSP) and the associated metals in the counties of Charqueadas and Sapucaia do Sul at the state of Rio Grande do Sul. The TSP samples were collected using high volume samplers and the analysis of the metallic elements was accomplished through ICP-AES. The results revealed that the TSP concentrations, found in the two studied regions, have exceded the current air quality patterns established by the Brazilian Legislation. They also revealed high levels of several of the elements being attributed to the presence of anthropogenic sources. The correlation between meteorological data (speed and wind direction) and TSP concentrations were significant and revealed strong influence in particle dispersion.

Análises seqüenciais de agrupamentos aplicadas ao estudo de partículas atmosféricas

The present paper has as objective to apply a sequential Cluster Analysis to the atmospheric particles: Hierarchical Cluster Analysis followed by Nonhierarchical Cluster Analysis. The hierarchical cluster analysis results were used as start point for the nonhierarchical cluster analysis as an agglomerative technique. These particles were taken from two areas of the metropolitan region of Porto Alegre, Charqueadas and Sapucaia do Sul., from may /97 to may/98, using a High Volume Sampler (Hi-Vol). Around 10,000 particles were analysed by Scanning Electron Microscope with Energy-Dispersive X-Ray microanalysis (SEM-EDS). The Hierarchical Cluster Analysis allowed the identification of five groups of particles, whose amounts were differentiated according to the summer and the winter campaigns. The abundance of each type of particles inside each group according to the different sections was verified by the Nonhierarchical Cluster Analysis, resulting in information about the emissions sources. The groups of particles of Si/Al and Si and of Fe/Zn and Fe for Charqueadas were more significant in section 2 and 3 (NW and W wind directions) and in section 1 (SE wind direction), evidencing the influence of the coal power plant and steel industry, respectively located in these quadrants. In Sapucaia do Sul the data were more heterogeneous, causing a certain difficulty to identify the source as anthropogenic. Nevertheless the group of particles containing Fe was found in sectors of NW/W wind directions which shows the influence of the steel plant.

Distinct aspects of pain catastrophizing according to chronic pain syndromes

Introduction: Catastrophizing is the tendency to magnify the threat value of pain and has been associated with measures of physical and psychological disability among individuals with several pain conditions. The aim of this study was to investigate whether pain catastrophizing is differentially associated with distinct pain syndromes. Methods: This is a cross-sectional study including 158 patients (40 with fibromyalgia, 25 with myofascial pain syndrome, 33 with chronic tensional type headache, 33 with endometriosis, and 27 with knee osteoarthritis) and 93 healthy subjects. The recruitment procedure occurred in concurrence with randomized controlled trials. Participants answered the following instruments: Brazilian Portuguese Pain-Catastrophizing Scale, Beck Depression Inventory II, State-Trait Anxiety Inventory, Pittsburgh Sleep Quality Index, visual analogue scale for pain, as well as a sociodemographic questionnaire. Results: For the total pain catastrophizing score, patients with endometriosis had significantly more catastrophizing thoughts than knee osteoarthritis (p < 0.05). Healthy participants had lower scores than any clinical group. More interestingly were the dimensions of pain catastrophizing, which showed significant differences in more than two groups, especially magnification scores, since these scores were able to discriminate, in a particular way, the majority of clinical samples from each other. We also observed differences between rumination, magnification and helplessness scores in all groups, suggesting that the characteristics of pain catastrophizing are distinct according to the pain disorder. Conclusions: The results suggest that dimensions of pain catastrophizing differ between pain syndromes. Therefore, it is important that researchers and clinicians focus on cognitive and emotional aspects of pain perception to have more successful interventions. Keywords: Chronic pain; catastrophizing; cross-sectional study

Home-Based Transcranial Direct Current Stimulation Device Development: An Updated Protocol Used at Home in Healthy Subjects and Fibromyalgia Patients

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation (NIBS) method, which modulates the membrane potential of neurons in the cerebral cortex by a low-intensity direct current. tDCS is a low-cost technique with minimal adverse effects and easy application. This neurostimulation method has a promising future to improve pain therapy, treatment of neuropsychiatric disorders, and physical rehabilitation. Current studies demonstrate the benefits of using tDCS over consecutive multiple sessions. However, the daily displacement to the specialized centers, travel costs, and disruptions to daily activities are some of the difficulties faced by patients. Thus, to be more comfortable, easy-to-use, and not disrupt daily commitments, a home-based tDCS was designed. Therefore, the objective of this study was to evaluate the feasibility of a portable tDCS device for home use in healthy subjects and fibromyalgia patients. Despite increased tDCS use and a reasonably large body of research on the effects across a range of clinical conditions, there is a limited amount of research on developing secure devices that guarantee the dose and contain a block system to avoid excessive use. Therefore, we used a tDCS device with a security system to permit daily use for 20 minutes with a minimal interval of 12 hours between sessions. A programmer preconfigures the equipment, which has a neoprene cap that allows the electrode positions in any assembly, according to individualized protocols for treatments or research. After, researchers can assess the effectiveness of treatment, and its adherence using information kept in the device software. Results suggest that the device is feasible for home use, with proper monitoring of adherence and contact impedance. There were reports of a few adverse effects, which do not differ from those reported in the literature in studies with the treatment under direct supervision.