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IntroductionWhile numerous studies have documented evidence for plasticity of the human brain there is little evidence that the human spinal cord can change after injury. Here, we employ a novel spinal fMRI design where we stimulate normal and abnormal sensory dermatomes in persons with traumatic spinal cord injury and perform a connectivity analysis to understand how spinal networks process information.MethodsSpinal fMRI data was collected at 3 Tesla at two institutions from 38 individuals using the standard SEEP functional MR imaging techniques. Thermal stimulation was applied to four dermatomes in an interleaved timing pattern during each fMRI acquisition. SCI patients were stimulated in dermatomes both above (normal sensation) and below the level of their injury. Sub-group analysis was performed on healthy controls (n = 20), complete SCI (n = 3), incomplete SCI (n = 9) and SCI patients who recovered full function (n = 6).ResultsPatients with chronic incomplete SCI, when stimulated in a dermatome of normal sensation, showed an increased number of active voxels relative to controls (p = 0.025). There was an inverse relationship between the degree of sensory impairment and the number of active voxels in the region of the spinal cord corresponding to that dermatome of abnormal sensation (R(2) = 0.93, pConclusionsIn this work we demonstrate the use of spinal fMRI to investigate changes in spinal processing of somatosensory information in the human spinal cord. We provide evidence for plasticity of the human spinal cord after traumatic injury based on an increase in the average number of active voxels in dermatomes of normal sensation in chronic SCI patients and an increased number of intraspinal connections in incomplete SCI patients relative to healthy controls.

We demonstrate a new sensitive biosensor for detection of vital fungal spores of Aspergillus niger. The biosensor is based on silicon microfabricated cantilever arrays operated in dynamic mode. The change in resonance frequency of the sensor is a function of mass binding to the cantilever surface. For specific A. niger spore immobilization on the cantilever, each cantilever was individually coated with anti-Aspergillus niger polyclonal antibodies. We demonstrate the detection of single A. niger spores and their subsequent growth on the functionalized cantilever surface by online measurements of resonance frequency shifts. The new biosensor operating in humid air allows quantitative and qualitative detection of A. niger spores as well as detection of vital, functional spores in situ within ∼4 h. The detection limit of the sensor is 103 CFU mL−1. Mass sensitivity of the cantilever sensor is ∼53 pg Hz−1. [ABSTRACT FROM AUTHOR]