DTA

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Tesi etd-09282018-124211

Type of thesis
Perfezionamento
Author
DEDOLA, FRANCESCA
URN
etd-09282018-124211
Title
Invasive and non invasive methods for bioelectronic medicine applications
Scientific disciplinary sector
ING-IND/34
Course
INGEGNERIA - Biorobotics
Committee
relatore MICERA, SILVESTRO
Keywords
  • bioelectronic medicine
  • leech
  • pig
  • ultrasound stimulation
  • vagus nerve
Exam session start date
;
Availability
parziale
Abstract
Bioelectronic medicine carries the promise to provide a personalized therapy for a specific disease, avoiding side effects produced by standard pharmacologic approaches. It relies on the employment of different forms of energy to modulate nervous system activity and restore physiologic conditions. However, nervous system language is far from being completely understood or even characterized.<br>This work will present our steps towards neural patterns decoding, through anatomical investigations on pig model and implementation of a robust experimental setup for recording/stimulation of neural activity by means of intraneural electrodes.<br>Envisioning a future non invasive targeted stimulation, we identified in ultrasound (US) stimulation a valid alternative to electrical (EL) based approaches. US stimulation allows a focused, reversible and non invasive stimulation of neural tissue; however, the effect of US stimulation on excitable tissue is still unknown.<br>This thesis will elucidate the fundamental mechanism(s) by which US can excite/inhibit neurons of a simple animal model, the leech.<br>Experimental outcomes of US stimulation of leech nociceptive (N) neurons will be presented, thus demonstrating the mechanical effects produced by USs elicited spikes on the cells.<br>More than 50 % of the recorded neurons responded with spikes to US stimulation and the success rate analysis suggests a threshold mechanism whose driving parameter is mainly US stimulus intensity.<br>Intracellular recordings showed that membrane depolarization is linearly dependent on stimulus intensity, and a persistence of the residual depolarization effect can be observed.<br>Action potentials induced by US and EL stimulation are different, in amplitude and duration, while the combination of the two shows high similarities, suggesting that the two forms of energy have different mechanism(s) of action but the involved ionic channels/membrane proteins in the spiking activity may be the same.<br><br>
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