White-matter microstructural changes in episodic menstrual migraine compared with hormonal controls

Question: Do patients with episodic menstrual migraine exhibit white-matter microstructural changes? Methods: 14 women with episodic menstrual migraine (35±8yrs) were assessed during interictal phase together with 11 healthy women (29±10yrs) during a matching phase of their menstrual cycle (post-ovulation). 2D-EPI multi-shell DWI data were acquired on a 3T Siemens Vida (64-ch coil) and preprocessed using DESIGNER [1]. Diffusion tensor / kurtosis imaging (DTI/DKI) parameter maps were estimated and skeletonised [2] and histogram-metrics were computed for each subject: median, peak height, width, and value. Results: Voxelwise statistical analysis [3] revealed multiple whitematter regions with lower MD and AD in patients, with no differences in FA and RD. Interestingly, migraineurs showed increased MK, AK and RK. Moreover, significant groups differences (Mann- Whitney test with Bonferroni correction) were found in histogram-metrics MD peak value, AD median and peak height and AK median. Median AK was positively associated (Spearman correlation) with disease duration but not with attack frequency and pain intensity. Conclusion: Our findings extended previous reports of whitematter microstructural changes in migraineurs across multiple brain regions [4, 5]. DKI histogram-metrics showed potential as disease biomarkers.info:eu-repo/semantics/publishedVersio

Dynamic functional connectivity in migraine during the interictal phase: a resting-state fMRI study

Question: Migraine is a cyclic and complex disorder, characterized by attacks of headache, sensory and cognitive disturbances1. Thalamocortical connectivity in migraine has been found to be transiently abnormal2. Our aim was to assess if the dynamical properties of the migraine brain are affected during the interictal phase. Methods: Resting-state functional MRI data was collected from 14 menstrual migraine patients without aura (interictal phase) and 12 healthy controls (menstrual post-ovulation phase). fMRI data processing included3: motion and distortion correction, temporal highpass filter, regression of motion and physiological confounds, spatial smoothing, and parcellation with the Desikan atlas. Dynamic functional connectivity (dFC) between regions was computed using phase coherence, and recurrent dFC states were identified by kmeans clustering (k ranging between 3 and 15) of the leading eigenvectors of dFC in each time point4. Permutation tests were performed to evaluate statistically significant differences between patients and controls in the probability of occurrence and the mean lifetime of the dFC states. Results: Similar dFC states were found consistently across different numbers of clusters, k, which resembled the canonical resting-state networks as expected. Compared to healthy controls, migraine patients show a significantly lower mean lifetime in one dFC state, when grouping in 4, 5 and 6 clusters. No differences were found for the probability of occurrence. Conclusions: Migraine may be linked to a disruption of brain networks dynamics. This emphasizes the need to adopt time-resolved methods, in addition to static, to study functional connectivity, to better understand the mechanisms of migraine. Our next step will be to assess the dynamics of the migraine brain throughout the migraine cycle.info:eu-repo/semantics/publishedVersio

Impact of susceptibility-induced distortion correction on perfusion imaging by pCASL with a segmented 3D GRASE readout

Purpose: The consensus for the clinical implementation of arterial spin labeling (ASL) perfusion imaging recommends a segmented 3D Gradient and Spin-Echo (GRASE) readout for optimal signal-to-noise-ratio (SNR). The correction of the associated susceptibility-induced geometric distortions has been shown to improve diagnostic precision, but its impact on ASL data has not been systematically assessed and it is not consistently part of pre-processing pipelines. Here, we investigate the effects of susceptibility-induced distortion correction on perfusion imaging by pseudo-continuous ASL (pCASL) with a segmented 3D GRASE readout. Methods: Data acquired from 28 women using pCASL with 3D GRASE at 3T was analyzed using three pre-processing options: without distortion correction, with distortion correction, and with spatial smoothing (without distortion correction) matched to control for blurring effects induced by distortion correction. Maps of temporal SNR (tSNR) and relative perfusion were analyzed in eight regions-of-interest (ROIs) across the brain. Results: Distortion correction significantly affected tSNR and relative perfusion across the brain. Increases in tSNR were like those produced by matched spatial smoothing in most ROIs, indicating that they were likely due to blurring effects. However, that was not the case in the frontal and temporal lobes, where we also found increased relative perfusion with distortion correction even compared with matched spatial smoothing. These effects were found in both controls and patients, with no interactions with the participant group. Conclusion: Correction of susceptibility-induced distortions significantly impacts ASL perfusion imaging using a segmented 3D GRASE readout, and this step should therefore be considered in ASL pre-processing pipelines. This is of special importance in clinical studies, reporting perfusion across ROIs defined on relatively undistorted images and when conducting group analyses requiring the alignment of images across different subjects.info:eu-repo/semantics/publishedVersio

O Impacto do Estádio no Consumo do Torcedor: como a Frequência no Estádio Impulsiona a Demanda por Produtos dos Clubes

The aim of this study is to investigate the relationship between the presence of supporter in the stadium, which demonstrates the supporter’s involvement with his soccer club, and its influence on the purchase of official products of the 12 largest Brazilian brands of soccer clubs. In this research, it was collected information from 1,296 supporters who responded to a questionnaire with 22 questions. It was defined as involvement with their soccer club the frequency this supporter goes to the stadium. In order to determine the consumption relationship it were used variables such as frequency of purchase of official products, the annual amount spent on such products, favorite venue to purchase and assortment of the products mix. For the supporters buying preferences analysis, it was applied the technique of correspondence analysis (Anacor). As a result, we can point out that the supporters’ loyalty, driven by the relationship marketing, is one of the catalysts for increasing the soccer clubs revenue, since the higher the products and average tickets purchase frequency, the more this frequency is associated with a higher number of attendance to the stadium, as well as the variety in the mix of products acquired by the supporter. In this sense, the work points to the importance of building a long term relationship which goes beyond the emotional bond with the club, reaching the brand products consumption.O objetivo deste estudo é investigar a relação existente entre a presença do torcedor no estádio, que demonstra o envolvimento do torcedor com seu clube de futebol, e sua influência na compra de produtos oficiais das 12 maiores marcas brasileiras de clubes de futebol. Nesta pesquisa, coletaram-se informações de 1.296 torcedores que responderam a um questionário com 22 perguntas. Definiu-se como envolvimento com seu clube de futebol a frequência de ida ao estádio. Para determinar a relação de consumo, foram utilizadas variáveis como frequência de compra de produtos oficiais, valor anual gasto com tais produtos, local preferido para realização de compras e sortimento do mix de produto. Para a análise das preferências de compra do torcedor, foi aplicada a técnica de análise de correspondência (Anacor). Como resultado, pode-se apontar que a fidelização do torcedor, impulsionada pelo marketing de relacionamento, é um dos catalisadores para aumentar as receitas dos clubes de futebol, já que maiores frequências de compra e tíquetes médios estão associadas a um número maior de idas ao estádio, assim como à variedade do mix de produtos adquiridos pelo torcedor. Nesse sentido, o trabalho aponta para a importância de construir uma relação de longo prazo que vá além do vínculo emocional com o clube, chegando até ao consumo dos produtos da marca

Brain perfusion imaging by multi‐delay arterial spin labeling: Impact of modeling dispersion and interaction with denoising strategies and pathology

Purpose: Arterial spin labeling (ASL) acquisitions at multiple post-labeling delays may provide more accurate quantification of cerebral blood flow (CBF), by fitting appropriate kinetic models and simultaneously estimating relevant parameters such as the arterial transit time (ATT) and arterial cerebral blood volume (aCBV). We evaluate the effects of denoising strategies on model fitting and parameter estimation when accounting for the dispersion of the label bolus through the vasculature in cerebrovascular disease. Methods: We analyzed multi-delay ASL data from 17 cerebral small vessel disease patients (50 ± 9 y) and 13 healthy controls (52 ± 8 y), by fitting an extended kinetic model with or without bolus dispersion. We considered two denoising strategies: removal of structured noise sources by independent component analysis (ICA) of the control-label image timeseries; and averaging the repetitions of the control-label images prior to model fitting. Results: Modeling bolus dispersion improved estimation precision and impacted parameter values, but these effects strongly depended on whether repetitions were averaged before model fitting. In general, repetition averaging improved model fitting but adversely affected parameter values, particularly CBF and aCBV near arterial locations in patients. This suggests that using all repetitions allows better noise estimation at the earlier delays. In contrast, ICA denoising improved model fitting and estimation precision while leaving parameter values unaffected. Conclusion: Our results support the use of ICA denoising to improve model fitting to multi-delay ASL and suggest that using all control-label repetitions improves the estimation of macrovascular signal contributions and hence perfusion quantification near arterial locations. This is important when modeling flow dispersion in cerebrovascular pathology

Mitochondria-targeted antioxidant MitoQ ameliorates ischaemia-reperfusion injury in kidney transplantation models.

BACKGROUND: Ischaemia-reperfusion (IR) injury makes a major contribution to graft damage during kidney transplantation. Oxidative damage to mitochondria is an early event in IR injury. Therefore, the uptake, safety, and efficacy of the mitochondria-targeted antioxidant MitoQ were investigated in models of transplant IR injury. METHODS: MitoQ uptake by warm and cooled pairs of pig and declined human kidneys was measured when preserved in cold static storage or by hypothermic machine perfusion. Pairs of pigs' kidneys were exposed to defined periods of warm and cold ischaemia, flushed and stored at 4°C with or without MitoQ (50 nmol/l to 250 µmol/l), followed by reperfusion with oxygenated autologous blood in an ex vivo normothermic perfusion (EVNP). Pairs of declined human kidneys were flushed and stored with or without MitoQ (5-100 µmol/l) at 4°C for 6 h and underwent EVNP with ABO group-matched blood. RESULTS: Stable and concentration-dependent uptake of MitoQ was demonstrated for up to 24 h in pig and human kidneys. Total blood flow and urine output were significantly greater in pig kidneys treated with 50 µmol/l MitoQ compared with controls (P = 0.006 and P = 0.007 respectively). In proof-of-concept experiments, blood flow after 1 h of EVNP was significantly greater in human kidneys treated with 50 µmol/l MitoQ than in controls (P ≤ 0.001). Total urine output was numerically higher in the 50-µmol/l MitoQ group compared with the control, but the difference did not reach statistical significance (P = 0.054). CONCLUSION: Mitochondria-targeted antioxidant MitoQ can be administered to ischaemic kidneys simply and effectively during cold storage, and may improve outcomes after transplantation

Termografia infravermelha em tempo real como método de avaliação da viabilidade do baço em modelo de esplenectomia parcial em porcos

OBJETIVO: Determinar se a termografia infravermelha é capaz de detectar com precisão a perda de perfusão tecidual em áreas de parênquima esplênico. MÉTODOS: Cinco porcos Landrace pesando entre 12 a 15 kg, após medicação pré-anestésica intramuscular e anestesia por infusão endovenosa, foram submetidos a quatro etapas de ligaduras sequenciais, dos vasos arteriais para o pólo inferior do baço: 1-vasos do ligamento esplênico; 2-ramo da artéria esplênica para o pólo inferior; 3-ramo arterial para o pólo inferior na face visceral do órgão; 4-parênquima esplênico dividindo o órgão. As imagens foram captadas por câmera Therma CAM SC500 instalada a 50 centímetros da superfície do órgão. As temperaturas foram medidas na região proximal (vascularizada) e na região distal (isquêmica), em três áreas circulares distintas de cada região através do software SAT Report, antes e após cada etapa de ligaduras, constituindo cinco grupos de medidas: tempo 0 = antes da etapa 1; tempo 1 = após etapa 1; tempo 2 = após etapa 2; tempo 3 = após etapa 3; tempo 4 = após etapa 4. RESULTADOS: Houve manutenção da temperatura da região proximal (vascularização preservada) durante todos os tempos de desvascularização. A temperatura da região distal (desvascularizada) iniciou queda a partir da primeira ligadura e tornou-se estatisticamente menor que a da região proximal a partir da ligadura 3 (Etapa 3). Houve diferença estatisticamente significativa entre as temperaturas proximais e distais do órgão na medida em que foram sendo realizadas as ligaduras vasculares. CONCLUSÃO: A termografia infravermelha foi capaz de distinguir com precisão áreas de parênquima esplênico com vascularização preservada de áreas isquêmicas e pode contribuir para a avaliação da viabilidade de órgãos sólidos