Brain Responses to Surprising Stimulus Offsets: Phenomenology and Functional Significance.

Abrupt increases of sensory input (onsets) likely reflect the occurrence of novel events or objects in the environment, potentially requiring immediate behavioral responses. Accordingly, onsets elicit a transient and widespread modulation of ongoing electrocortical activity: the Vertex Potential (VP), which is likely related to the optimisation of rapid behavioral responses. In contrast, the functional significance of the brain response elicited by abrupt decreases of sensory input (offsets) is more elusive, and a detailed comparison of onset and offset VPs is lacking. In four experiments conducted on 44 humans, we observed that onset and offset VPs share several phenomenological and functional properties: they (1) have highly similar scalp topographies across time, (2) are both largely comprised of supramodal neural activity, (3) are both highly sensitive to surprise and (4) co-occur with similar modulations of ongoing motor output. These results demonstrate that the onset and offset VPs largely reflect the activity of a common supramodal brain network, likely consequent to the activation of the extralemniscal sensory system which runs in parallel with core sensory pathways. The transient activation of this system has clear implications in optimizing the behavioral responses to surprising environmental changes.

A comparative study of antibacterial and anti-inflammatory effects of mouthrinse containing tea tree oil.

The study evaluated the antibacterial and anti-inflammatory efficacy, domiciliary oral hygiene, of a mouthrinse containing Tea Tree Oil (TTO) comparing it with two mouthrinses containing chlorhexidine 0,12% respectively and essential oils, and a placebo. MATERIALS AND METHODS: A pilot study, randomized 4 × 4, controlled, cross-over, double-blind. 16 subjects with gingivitis (7 males and 9 females) aged 21-37 years, were randomly divided into four groups based on mouthwash that had to be used for domiciliary oral hygiene: mouthwash with essential oils, mouthwash with chlorhexidine 0,12 %, mouthwash containig tea tree oil and mouthwash placebo. Clinical evaluation was performed by: Full Mouth Plaque Score (FMPS), Full Mouth Bleeding Score (FMBS), Gingival Index (GI), discolorations, language examination and alteration of taste. The data were recorded before and 2 weeks after treatment. RESULTS: Statistical analysis shows that treatments with tea tree oil, essential oils and chlorhexidine are effective. Comparing treatments should be noted that the tea tree oil gives a greater improvement in the GI and FMBS, while it is the least effective in the control of bacterial plaque. CONCLUSION: Although further studies are needed, the anti-inflammatory properties of the mouthwash made from TTO would seem to be a valuable non-toxic adjunct in the management of gingivitis.

Association between pollen exposure and nasal cytokines in grass pollen-allergic children

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Prognostic factors in children with PRES and hematologic diseases.

OBJECTIVES: Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological entity characterized by focal neurological signs, headache, confusion, and seizure, associated with transitory lesions in the posterior areas of the brain detectable with neuroimaging. Among children, one of the most common causes of PRES is cancer. MATERIALS AND METHODS: In this review, we present the cases of 5 children developing PRES after stem cell transplantation for hematological disease and review all the cases reported in English literature to investigate outcomes and associated risk factors. RESULTS: One hundred and eleven cases were reported. Hypertension was very frequent (80%). Clinical features included seizures (80.1%), headache (44.1%), visual disturbance (26.1%), and mental change (48.6%). EEG was abnormal in 27 of 32 patients. MRI revealed characteristic lesions in all patients even in early stages. Abnormal MRI findings in late stages were associated with neurological sequelae. Nineteen patients died (17.1%) of which 2 of PRES. Among alive patients, 17 had neurological sequelae. Four cases of PRES relapse were described. CONCLUSIONS: Thus, all transplant recipients with symptoms consistent with PRES should be promptly recognized to avoid long-term complications or even death.

Evaluation of a web-based network for reproducible T2* MRI assessment of iron overload in thalassemia.

PURPOSE: To build and evaluate a national network able to improve the care of thalassemia, a genetic disorder in haemoglobin synthesis often associated with iron accumulation in a variety of organs, due to the continuous blood transfusions. METHODS: The MIOT (Myocardial Iron Overload in Thalassemia) network is constituted by thalassemia and magnetic resonance imaging (MRI) centers. Thalassemia centers are responsible for patient recruitment and collection of anamnestic and clinical data. MRI centers have been equipped with a standardized acquisition technique and an affordable workstation for image analysis. They are able to perform feasible and reproducible heart and liver iron overload assessments for a consistent number of thalassemia patients in a robust manner. All centers are linked by a web-based network, configured to collect and share patient data. RESULTS: On 30th March 2008, 695 thalassemia patients were involved in the network. The completion percentage of the patient records in the database was 85+/-6.5%. Six hundred and thirteen patients (88%) successfully underwent MRI examination. Each MRI center had a specific absorption capacity that remained constant over time, but the network was capable of sustaining an increasing number of patients due to continuous enrollment of new centers. The patient's comfort, assessed as the mean distance from the patient home locations to the MRI centers, significantly increased during the network's evolution. CONCLUSION: The MIOT network seems to be a robust and scalable system in which T2* MRI-based cardiac and liver iron overload assessment is available, accessible and reachable for a significant and increasing number of thalassemia patients in Italy (about 420 per year), reducing the mean distance from the patient locations to the MRI sites from 951km to 387km. A solid, wide and homogeneous database will constitute an important scientific resource, shortening the time scale for diagnostic, prognostic and therapeutical evidence-based research on the management of thalassemia disease.