Changes in MEG resting-state networks are related to cognitive decline in type 1 diabetes mellitus patients

OBJECTIVE: Integrity of resting-state functional brain networks (RSNs) is important for proper cognitive functioning. In type 1 diabetes mellitus (T1DM) cognitive decrements are commonly observed, possibly due to alterations in RSNs, which may vary according to microvascular complication status. Thus, we tested the hypothesis that functional connectivity in RSNs differs according to clinical status and correlates with cognition in T1DM patients, using an unbiased approach with high spatio-temporal resolution functional network.; METHODS: Resting-state magnetoencephalographic (MEG) data for T1DM patients with (n=42) and without (n=41) microvascular complications and 33 healthy participants were recorded. MEG time-series at source level were reconstructed using a recently developed atlas-based beamformer. Functional connectivity within classical frequency bands, estimated by the phase lag index (PLI), was calculated within eight commonly found RSNs. Neuropsychological tests were used to assess cognitive performance, and the relation with RSNs was evaluated.; RESULTS: Significant differences in terms of RSN functional connectivity between the three groups were observed in the lower alpha band, in the default-mode (DMN), executive control (ECN) and sensorimotor (SMN) RSNs. T1DM patients with microvascular complications showed the weakest functional connectivity in these networks relative to the other groups. For DMN, functional connectivity was higher in patients without microangiopathy relative to controls (all p<0.05). General cognitive performance for both patient groups was worse compared with healthy controls. Lower DMN alpha band functional connectivity correlated with poorer general cognitive ability in patients with microvascular complications.; DISCUSSION: Altered RSN functional connectivity was found in T1DM patients depending on clinical status. Lower DMN functional connectivity was related to poorer cognitive functioning. These results indicate that functional connectivity may play a key role in T1DM-related cognitive dysfunction

Reshaping cortical connectivity in traumatic spinal cord injury: a novel effect of hyperbaric oxygen therapy

Introduction: Spinal cord injuries (SCIs) represent a severe neuro-traumatic occurrence and an excruciating social burden. Though the hyperbaric oxygen (HBO2) has been credited as a first line therapeutic resource for SCIs, its mechanism of action in the spine is only partially known, while the impingement upon other areas of the nervous system deserves additional investigation. In this study we deem to describe a novel effect of HBO2 in a subject affected by SCI who, along with the clinical improvement, showed a reshaped connectivity in cortical sensory-motor areas. Case presentation: A 45 years male presenting severe sensory-motor symptoms following a spinal lesion partially involving the C1 segment was successfully treated with HBO2 cycles. After the dramatic improvement reflected by an excellent optimization of the single performances, it has been investigated whether this result would reveal not only an intrinsic effect upon the spinal cord, but also a better connectivity strength in sensory-motor cortical regions. The results obtained by implementing EEG recordings with EEGLAB auto regressive vector plugins indeed suggest a substantial reshaping of cortico-cortical connectivity after HBO2. Discussion: These results show a correlation between positive clinical evolution and a new modulation of cortical connectivity. Though further clinical investigations would clarify as to whether HBO2 might be directly or epiphenomenally involved in this aspect of the network architecture, our report suggests that a comparison between clinical results and the study of brain connectivity represent a holistic approach in investigating the physiopathology of SCIs and in monitoring the treatment

Thymosin beta 4 expression in normal skin, colon mucosa and in tumor infiltrating mast cells

Mast cells (MCs) are metachromatic cells that originate from multipotential hemopoietic stem cells in the bone marrow. Two distinct populations of MCs have been characterized: mucosal MCs are tryptase-positive while mast cells in skin contain tryptase and chymase. We now show that a sub-population of MCs is highly immunoreactive for thymosin β4, as revealed by immunohistochemical analyses of normal skin, normal colon mucosa and salivary gland tumors. Four consecutive serial sections from each case were immunostained for thymosin β4 (Tβ4), chymase, tryptase and stained for toluidine blue. In skin biopsies, MCs showed a comparable immunoreactivity for Tβ4, chymase and tryptase. In normal colon mucosa the vast majority of mucosal MCs expressed a strong cytoplasmic immunoreactivity for tryptase and for Tβ4, in the absence of chymase reactivity. A robust expression of Tβ4 was detected in tumor-infiltrating and peritumoral mast cells in salivary gland tumors and breast ductal infiltrating carcinomas. Tumorinfiltrating MCs also showed a strong immunoreactivity for chymase and tryptase. In this paper, we first demonstrate that normal dermal and mucosal mast cells exhibit strong expression of thymosin β4, which could be considered a new marker for the identification of mast cells in skin biopsies as well as in human tumors. The possible relationship between the degree of Tβ4 expression in tumor-infiltrating mast cells and tumor behaviour warrants further consideration in future investigations

EEG functional network topology is associated with disability in patients with amyotrophic lateral sclerosis

Amyotrophic Lateral Sclerosis (ALS) is one of the most severe neurodegenerative diseases, which is known to affect upper and lower motor neurons. In contrast to the classical tenet that ALS represents the outcome of extensive and progressive impairment of a fixed set of motor connections, recent neuroimaging findings suggest that the disease spreads along vast non-motor connections. Here, we hypothesised that functional network topology is perturbed in ALS, and that this reorganization is associated with disability. We tested this hypothesis in 21 patients affected by ALS at several stages of impairment using resting-state electroencephalography (EEG) and compared the results to 16 age-matched healthy controls. We estimated functional connectivity using the Phase Lag Index (PLI), and characterized the network topology using the minimum spanning tree (MST). We found a significant difference between groups in terms of MST dissimilarity and MST leaf fraction in the beta band. Moreover, some MST parameters (leaf, hierarchy and kappa) significantly correlated with disability. These findings suggest that the topology of resting-state functional networks in ALS is affected by the disease in relation to disability. EEG network analysis may be of help in monitoring and evaluating the clinical status of ALS patients

Low-Cost 3D Devices and Laser Scanners Comparison for the Application in Orthopaedic Centres

Low-cost 3D sensors are nowadays widely diffused and many different solutions are available on the market. Some of these devices were developed for entertaining purposes, but are used also for acquisition and processing of different 3D data with the aim of documentation, research and study. Given the fact that these sensors were not developed for this purpose, it is necessary to evaluate their use in the capturing process. This paper shows a preliminary research comparing the Kinect 1 and 2 by Microsoft, the Structure Sensor by Occipital and the O&amp;P Scan by Rodin4D in a medical scenario (i.e. human body scans). In particular, these sensors were compared to Minolta Vivid 9i, chosen as reference because of its higher accuracy. Different test objects were analysed: a calibrated flat plane, for the evaluation of the systematic distance error for each device, and three different parts of a mannequin, used as samples of human body parts. The results showed that the use of a certified flat plane is a good starting point in characterizing the sensors, but a complete analysis with objects similar to the ones of the real context of application is required. For example, the Kinect 2 presented the best results among the low-cost sensors on the flat plane, while the Structure Sensor was more reliable on the mannequin parts