Automatic detection of tic activity in the Tourette Syndrome Bernabei, M; Andreoni, G; Mendez Garcia, Martin O ...
2010 Annual International Conference of the IEEE Engineering in Medicine and Biology,
01/2010, Letnik:
2010
Conference Proceeding, Journal Article
This study presents a simple decision-support system for the detection of tic events during the Tourette Syndrome (TS). The system is based on a triaxial accelerometer placed on the patient's trunk. ...TS is a neurological disorder that emerges during childhood and that is characterized by a large spectrum of involuntary/compulsive movements and sounds. 12 subjects with chronic TS participated in the study and the tic events were both measured by the proposed device and visually classified through video recording. 3D-acceleration timeseries were combined through a module operator and their noise was eliminated by a median filter. Signal to noise ratio was improved by a nonlinear energy operator. Finally, a time-variant threshold was used to detect tic events. The automatic tic recognition showed a performance around 80% in terms of sensitivity, specificity and accuracy. In conclusion, this simple, automatic and unobtrusive method offers an alternative approach to quantitatively assess the tic events in clinical and non clinical environments. This overcomes the limitations of the current motor tic evaluation which is done by clinical observation and/or video-inspection in specialized neurological centres.
Abnormalities of coagulation are common in patients with acute nonlymphoblastic leukemia, although the mechanisms involved are unclear, except in a few cases. To investigate the pathogenesis of this ...coagulopathy, suspensions of purified leukemic cells were prepared and tested for procoagulant activity. Neither the leukemic cells nor their supernatants directly accelerated the clotting of plasma. Since the leukemic cells did not possess direct procoagulant activity, their ability or inability to elaborate a mediator of cellular coagulant properties, interleukin-1, was studied. Leukemic cells from patients with coagulopathy elaborated interleukin-1, and addition of phytohemagglutinin increased interleukin-1 release. In contrast, no interleukin-1 was released, before or after stimulation with phytohemagglutinin, from leukemic cells from patients without coagulopathy. Leukemic cells from another group of patients with abnormalities of coagulation released interleukin-1 only after phytohemagglutinin treatment. In terms of the coagulation mechanism, interleukin-1 containing supernatants from leukemic cell cultures induced the procoagulant receptor tissue factor, a co-factor in the initiation of coagulation, on the endothelial cell surface. There was coordinate suppression of the anticoagulant endothelial cell receptor thrombomodulin, a co-factor for the antithrombotic protein C pathway. Antibody to interleukin-1 prevented these changes in cellular coagulant properties. Taken together, these changes result in a shift in the balance of endothelial cell coagulant properties to an activated state in which mechanisms promoting procoagulant reactions on the vessel surface predominate. Synthesis and release of the mediator interleukin-1 by leukemic cells thus defines a new mechanism through which malignant cells can potentially activate the coagulation mechanism.
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