Stem/progenitor cell transplantation delivery of astrocytes is a potentially powerful strategy for spinal cord injury (SCI). Axon extension into SCI lesions that occur spontaneously or in response to experimental manipulations is often observed along endogenous astrocyte “bridges,” suggesting that augmenting this response via astrocyte lineage transplantation can enhance axon regrowth. Given the importance of respiratory dysfunction post-SCI, we transplanted glial-restricted precursors (GRPs)—a class of lineage-restricted astrocyte progenitors—into the C2 hemisection model and evaluated effects on diaphragm function and the growth response of descending rostral ventral respiratory group (rVRG) axons that innervate phrenic motor neurons (PhMNs). GRPs survived long term and efficiently differentiated into astrocytes in injured spinal cord. GRPs promoted significant recovery of diaphragm electromyography amplitudes and stimulated robust regeneration of injured rVRG axons. Although rVRG fibers extended across the lesion, no regrowing axons re-entered caudal spinal cord to reinnervate PhMNs, suggesting that this regeneration response—although impressive—was not responsible for recovery. Within ipsilateral C3–5 ventral horn (PhMN location), GRPs induced substantial sprouting of spared fibers originating in contralateral rVRG and 5-HT axons that are important for regulating PhMN excitability; this sprouting was likely involved in functional effects of GRPs. Finally, GRPs reduced the macrophage response (which plays a key role in inducing axon retraction and limiting regrowth) both within the hemisection and at intact caudal spinal cord surrounding PhMNs. These findings demonstrate that astrocyte progenitor transplantation promotes significant plasticity of rVRG-PhMN circuitry and restoration of diaphragm function and suggest that these effects may be in part through immunomodulation.
Purpose:The aim of this study was to determine the impact of OrCam on vision-related quality of life of patients with legal blindness and end-stage glaucoma. OrCam is a device comprised of a camera and earpiece attached to the user’s eyeglass that translates written text to speech.Methods:In this prospective, observational study, a total of 27 participants were recruited and tested. All participants were legally blind. Participants were provided with the OrCam device during the study period and trained how to operate it. National Eye Institute Visual Functioning Questionnaire-25 (NEI-VFQ-25) and other questionnaires were given to participants at the baseline visit and at the end of the 4-week study for comparison. Additional questions were surveyed weekly during the study to monitor progress.Results:At the final visit after 1 month, most participants, 74.1% ( n = 20/27), reported an increase in their overall quality of life. Participants were highly satisfied with the device; 88.9% ( n = 24/27) reported being “very satisfied” or “satisfied” with the device. The NEI-VFQ-25 near vision subscale score improved from 29.9 to 37.2 ( p = .045).Discussion:OrCam allowed participants with legal blindness to read independently when in controlled settings, subsequently improving their quality of life. However, users had more difficulty using the device when the location of text was not readily apparent (e.g., street signs, billboards), and users with some degree of vision had an easier time aligning the device with the text.Implications for practitioners:This device may offer participants with visual impairments the opportunity to read independently.
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