41Prokaryotic mechanosensitive (MS) channels have an intimate relationship with 42 membrane lipids. Membrane lipids may influence channel activity by directly 43 interacting with bacterial MS channels or by influencing the global properties of the 44 membrane such as area stretch and bending moduli. Previous work has implicated 45 membrane stiffness as a key determinant of the mechanosensitivity of E. coli (Ec)MscS. 46 Here we systematically tested this hypothesis using patch fluorometry of azolectin 47 liposomes doped with lipids of increasing area stretch moduli. Increasing DOPE 48 content of azolectin liposomes causes a rightward shift in the tension response curve of 49 EcMscS. These rightward shifts are further magnified by the addition of stiffer forms 50 of PE such as the branched chain lipid DPhPE and the fully saturated lipid DSPE. 51 Furthermore, a comparison of the branched chain lipid DPhPC to the stiffer DPhPE 52 showed a rightward shift in the tension response curve in the presence of the stiffer 53DPhPE. We show that these changes are not due to changes in membrane bending 54 rigidity as the tension threshold of EcMscS in membranes doped with PC18:1 and 55 PC18:3 are the same, despite a two-fold difference in their bending rigidity. We also 56 show that after prolonged pressure application sudden removal of force in softer 57 membranes causes a rebound reactivation of EcMscS and we discuss the relevance of 58 this phenomenon to bacterial osmoregulation. Collectively, our data demonstrate that 59 membrane stiffness is a key determinant of the mechanosensitivity of EcMscS. 60 61 62 65 This channel is the canonical member of a diverse family of MS channels that spans 66 prokaryotic and eukaryotic cell-walled organisms 3-5 . Purification and reconstitution of 67EcMscS, and many of its homologues, into lipid bilayers show that it gates according 68 to the force-from-lipid principle 6-8 . This means the channel is inherently 69 mechanosensitive and directly senses membrane forces that result in a conformational 70 change culminating in the channel opening. As a result, it is clear that membrane lipids 71 are a key driver of EcMscS activity. Recent evidence suggests that eukaryotic MS 72 channels also employ force-from-lipids gating 9-12 . Therefore, the basic biophysical 73 principles that govern the gating of prokaryotic channels may in turn provide insight 74 into the gating of eukaryotic MS channels 13, 14 . 76Liposomal reconstitution has for many years been successfully used not only to 77 document the inherent mechanosensitivity of both prokaryotic and eukaryotic ion 78 channels but also to probe the influence of individual lipids on MS channel function 15-79 17 . Lipids can influence integral membrane proteins such as MS channels in one of two 80 ways 18 . Firstly, the lipid may directly interact with the protein and modify function. The 81 second is that lipids may indirectly affect function via global effects on the mechanical 82 properties of the bilayer. For example, liposomal reconst...

Traumatic brain injury (TBI) can be caused by accidents like road traffic accidents (RTA), sports injuries, and injuries at home. It is a major health issue, very often fatal and causing high morbidity, changing the lives of both the person injured and the families involved. Anticipating and preventing secondary injury and seizures post-trauma, defining severity of TBI, predicting TBI outcomes and arousal from coma or declaration of vegetative state or brain death form pivotal checkpoints in TBI management. Other challenges faced include identifying malingerers from genuine individuals with post-TBI morbidity, defining the severity of previous TBI in the field or previous injuries when reports are lost. Depending on both its severity and location it can cause a variety of post-TBI cognitive, sensory and tactile, and motor impairments. In such instances the present paper looks at how the electroencephalographs (EEG) like NeuralScan can and do contribute uniquely and significantly aiding in assessment, continuous/periodic evaluation during the course of recovery, brain-retraining and rehabilitation in evaluating temporal changes in neuronal functionality following TBI.