William Tyler

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Although both extrinsic and intrinsic factors have been identified that orchestrate the differentiation and maturation of oligodendrocytes, less is known about the intracellular signaling pathways that control the overall commitment to differentiate. Here, we provide evidence that activation of the mammalian target of rapamycin (mTOR) is essential for(More)
While several major classes of neocortical neural precursor cells have been identified, the lineal relationships and molecular profiles of these cells are still largely unknown. Furthermore, the individual contribution of each cell class to neocortical growth during normal development and in neurodevelopmental disorders has not been determined. Using a(More)
Insulin-like growth factor (IGF)-I and IGF-II regulate brain development and growth through the IGF type 1 receptor (IGF-1R). Less appreciated is that IGF-II, but not IGF-I, activates a splice variant of the insulin receptor (IR) known as IR-A. We hypothesized that IGF-II exerts distinct effects from IGF-I on neural stem/progenitor cells (NSPs) via its(More)
Previous work from our laboratory demonstrated that the mammalian target of rapamycin (mTOR) is active during and required for oligodendrocyte progenitor cell (OPC) differentiation. Here, we applied an iTRAQ mass spectrometry-based proteomic approach to identify novel targets of the mTOR pathway during OPC differentiation. Among the 978 proteins identified(More)
Activation of the transcriptional regulator SlyA by the PhoP/PhoQ two-component system controls intracellular expression of numerous factors influencing Salmonella virulence. By dissecting the SlyA regulon using stable isotope labeling with amino acids in cell culture analysis, we found that SlyA enhances overall transcription of PhoP-activated loci. This(More)
Previously, we reported the isolation of a heparan sulfate-binding collagenous protein, p200, that is expressed by Schwann cells in developing peripheral nerves ((1996) J. Biol. Chem. 271, 13844-13853; (1999) J. Neurosci. Res. 56, 284-294). Here, we report the cloning of p200 cDNA from a Schwann cell cDNA library. The deduced amino acid sequence identifies(More)
Trisomy 21, or Down syndrome (DS), is the most common genetic cause of developmental delay and intellectual disability. To gain insight into the underlying molecular and cellular pathogenesis, we conducted a multi-region transcriptome analysis of DS and euploid control brains spanning from mid-fetal development to adulthood. We found genome-wide alterations(More)
Several neural precursor populations contemporaneously generate neurons in the developing neocortex. Specifically, radial glial stem cells of the dorsal telencephalon divide asymmetrically to produce excitatory neurons, but also indirectly to produce neurons via three types of intermediate progenitor cells. Why so many precursor types are needed to produce(More)
Six patients with cerebrospinal fluid (CSF) leaks and gram-negative bacillary meningitis (GNBM) were treated with large doses of intrathecal amikacin (20 to 40 mg daily) and systemic antibiotics. Bactericidal activity was measured in the CSF of each patient, and the dose of intrathecal amikacin was increased if bactericidal activity was absent. Five of six(More)
OBJECTIVE Capnography is an effective means of monitoring cardiopulmonary resuscitation and managing endotracheal intubation. Numerous studies have validated its use in urban settings, but none have described its integration into a rural EMS system. The authors describe the process of integrating capnography training and use in Jackson County, West(More)