Objective: Neurotrophin-3 (NT3) plays a key role in the development and function of locomotor circuits including descending serotonergic and corticospinal tract axons and afferents from muscle and skin. We have previously shown that gene therapy delivery of human NT3 into affected forelimb muscles improves sensorimotor recovery after stroke in adult and elderly rats. Here, to move toward the clinic, we tested the hypothesis that intramuscular infusion of NT3 protein could improve sensorimotor recovery after stroke.
View Article and Find Full Text PDFThere is an urgent need for a therapy that reverses disability after stroke when initiated in a time frame suitable for the majority of new victims. We show here that intramuscular delivery of neurotrophin-3 (NT3, encoded by NTF3) can induce sensorimotor recovery when treatment is initiated 24 h after stroke. Specifically, in two randomized, blinded preclinical trials, we show improved sensory and locomotor function in adult (6 months) and elderly (18 months) rats treated 24 h following cortical ischaemic stroke with human NT3 delivered using a clinically approved serotype of adeno-associated viral vector (AAV1).
View Article and Find Full Text PDFThe corticospinal tract (CST) can be completely severed unilaterally in the medullary pyramids of the rodent brainstem. The CST is a motor tract that has great importance for distal muscle control in humans and, to a lesser extent, in rodents. A unilateral cut of one pyramid results in loss of CST innervation of the spinal cord mainly on the contralateral side of the spinal cord leading to transient motor disability in the forelimbs and sustained loss of dexterity.
View Article and Find Full Text PDFAm J Alzheimers Dis Other Demen
February 2015
Background: The purpose of the current study was to investigate whether an informative Web site is effective at producing higher scores for an individual's knowledge of Alzheimer's disease (AD) relative to those who do not visit a Web site.
Methods: A total of 552 participants completed the study on Amazon's Mechanical Turk; half were randomly assigned to visit alz.org, while a control group did not.
Lesions of the spinal cord cause two distinctive types of neuroimmune responses, a response at the lesion site that leads to additional tissue destruction and a more subtle response, termed Wallerian degeneration (WD), that occurs distal to the lesion site. We have evidence that the neuroimmune response associated with WD may support tissue repair. Previously, we found that overexpression of neurotrophin-3 (NT-3) induced axonal growth in the spinal cord after a unilateral corticospinal tract (CST) lesion, but only if the immune system was intact and activated.
View Article and Find Full Text PDFThe assembly of neuronal circuits during development requires the precise navigation of axons, which is controlled by attractive and repulsive guidance cues. In the developing spinal cord, ephrinB3 functions as a short-range repulsive cue that prevents EphA4 receptor-expressing corticospinal tract and spinal interneuron axons from crossing the midline, ensuring proper formation of locomotor circuits. Here we report that the small GTPase RhoA, a key regulator of cytoskeletal dynamics, is also required for ephrinB3/EphA4-dependent locomotor circuit formation.
View Article and Find Full Text PDFAlthough large cholangiocytes exert their functions by activation of cyclic adenosine 3',5'-monophosphate (cAMP), Ca(2+)-dependent signaling regulates the function of small cholangiocytes. Histamine interacts with four receptors, H1-H4HRs. H1HR acts by Gαq activating IP(3)/Ca(2+), whereas H2HR activates Gα(s) stimulating cAMP.
View Article and Find Full Text PDFThe molecular mechanisms by which extracellular guidance cues regulate axonal morphology are not fully understood. Recent findings suggest that increased activity of the protein kinase Akt promotes dendritic branching and elongation in hippocampal neurons. We tested whether expression of constitutively active Akt (CA-Akt) in primary sensory neurons would promote axonal branching and whether targeting CA-Akt to lipid rafts, common sites of Akt function, would differentially regulate axonal morphology.
View Article and Find Full Text PDFThis paper evaluates the effects of adenoviral vector-mediated glial cell-derived neurotrophic factor (GDNF) gene delivery on survival of primary human corneal epithelial cells (PHCEC) established from limbal explants in vitro and the overexpression of GDNF gene in bioengineered human corneal constructs on substrate of corneal stromal discs followed by autograft ex vivo. In vitro, the overexpression of GDNF in the supernatant of PHCEC peaked at day 4, but lasted for at least 4 weeks after the transduction mediated by adenoviral vector. At day 10, the cell viability was 2-fold greater (P < 0.
View Article and Find Full Text PDFAfter an unilateral lesion of the corticospinal tract (CST) at the level of the medulla over-expression of Neurotrophin-3 (NT-3) in lumbar spinal cord motoneurons induced axonal sprouting of the intact CST in the acutely injured but not uninjured or chronically injured spinal cord in rats. This suggested that processes associated with immune-mediated wound healing may act with NT-3 to induce neuroplasticity. To test whether immune processes were involved we measured NT-3-induced axonal sprouting in immunosuppressed compared to immunocompetent rats.
View Article and Find Full Text PDFPurpose: To evaluate the expression patterns of neurotrophic factors (NTFs) and their receptors in the human cornea with the intention of exploring the role of NTFs in maintaining corneal epithelial stem cells in the limbus.
Methods: Fresh human corneoscleral tissues were prepared for frozen sections. Immunofluorescent staining was performed with primary antibodies against six members of three NTF families and their six receptors.
Nerve growth factor (NGF), a member of the neurotrophin family, has been identified as an essential growth factor supporting stem cell self-renewal outside the nervous system and was previously shown to stimulate corneal epithelial proliferation both in vivo and in vitro. In this study, we evaluated the expression of NGF and its corresponding receptors in the human corneal and limbal tissues, as well as in primary limbal epithelial cultures by immunofluorescent staining and relatively quantitative real-time polymerase chain reaction. We found that NGF was uniquely expressed in the human limbal basal epithelium, together with its two corresponding receptors: the high-affinity receptor TrkA and the low-affinity receptor p75NTR.
View Article and Find Full Text PDFMagn Reson Chem
November 2007
The Tobey-Simon (additivity) rule for aromatic groups which was devised about 40 years ago has been found to need revision. The rule shows an aromatic group attached to a C==C double bond as causing a downfield chemical shift of a cis-related vinylic proton and a small upfield shift of a trans-related proton. A search of data in the recent literature has shown that this rule should apply mainly to monosubstituted phenyl groups and some polynuclear aromatics.
View Article and Find Full Text PDFAddition of phenoxathiin cation radical (PO*+) to acyclic alkenes in acetonitrile (MeCN) solution occurred stereospecifically to form bis(10-phenoxathiiniumyl)alkane adducts. Stereospecific trans addition is ascribed to the intermediacy of an episulfonium cation radical. The alkenes used were cis- and trans-2-butene, cis- and trans-2-pentene, cis- and trans-4-methyl-2-pentene, cis- and trans-4-octene, trans-3-hexene, trans-3-octene, trans-5-decene, cis-2-hexene, and cis-2-heptene.
View Article and Find Full Text PDFMedulloblastoma is a common malignant brain tumor of childhood. Human epidermal growth factor receptor 2 (HER2) is expressed by 40% of medulloblastomas and is a risk factor for poor outcome with current aggressive multimodal therapy. In contrast to breast cancer, HER2 is expressed only at low levels in medulloblastomas, rendering monoclonal antibodies ineffective.
View Article and Find Full Text PDFPreviously, we reported that over-expression of neurotrophin-3 (NT-3) promoted sprouting of axons in the injured but not uninjured spinal cord, suggesting that processes associated with the injury such as Wallerian degeneration (WD) participated to induce the neuroplasticity. To determine whether NT-3-induced axonal sprouting depends upon processes associated with an acute injury, we uncoupled the injury and NT-3 over-expression in time. Rats were treated with a replicationdefective adenoviral vector carrying the NT-3 gene (Adv.
View Article and Find Full Text PDFThianthrene cation radical tetrafluoroborate (Th*+ BF4-) has been found to add to 2,3-dimethyl-2-butene (DMB) at 0 degrees C and -15 degrees C. The adduct, 2,3-dimethyl-2,3-(5,10-thianthreniumdiyl)butane ditetrafluoroborate (12), was isolated at -15 degrees C, and its 1H NMR spectrum was recorded at that temperature. The adduct was stable in CD3CN solution at -15 degrees C but decomposed slowly at 0 degrees C and quickly at 23 degrees C, forming the salt of 2,4,4,5,5-pentamethyl-2-oxazoline (8) with loss of thianthrene (Th).
View Article and Find Full Text PDFJ Neurosci Methods
September 2006
Current techniques used to quantify axons often rely upon manual quantification or potentially expensive commercially available programs for automated quantification. We describe a computerized method for the detection and quantification of axons in the rat CNS using readily available free software. Feature J, a java-based plug-in to the imaging software NIH Image J, faithfully detects linear structures such as axons in confocal or bright-field images using a Hessian-based algorithm.
View Article and Find Full Text PDF[structure: see text] Thianthrene cation radical tetrafluoroborate (Th*+ BF4(-)) added to the terminal alkynes 1-pentyne, 1-hexyne, 1-heptyne, 1-octyne, 1-nonyne, and 1-decyne to form trans-1,2-bis(5-thianthreniumyl)alkene tetrafluoroborates (1-6). Similarly, addition of phenoxathiin cation radical tetrafluoroborate (PO*+ BF4(-)) to the same alkynes gave 1,2-bis(10-phenoxathiiniumyl)alkene tetrafluoroborates (7-12). The trans configuration of two of the adducts (1 and 4) was shown with X-ray crystallography.
View Article and Find Full Text PDFNeurotrophins promote sprouting and elongation of central nervous system (CNS) axons following injury. Consequently, it has been suggested that neurotrophins could be used to repair the CNS by inducing axonal sprouting from nearby intact axons, thereby compensating for the loss of recently injured axons. We tested whether long-term overexpression of neurotrophins in the rat cortex would induce sprouting of cortical serotonergic axons following a neurotoxic injury.
View Article and Find Full Text PDF[reaction: see text] Thianthrene cation radical tetrafluoroborate (Th*+ BF4-) added to 2-butyne, 3-hexyne, 4-octyne, and 5-decyne in MeCN to form trans bisadducts R(Th+)C=C(Th+)R, where R = Me, Et, Pr, Bu (7a-d). Phenoxathiin cation radical tetrafluoroborate (PO*+ BF4-) added similarly to the last three alkynes to form adducts R(PO+)C=C(PO+)R, 8b-d. Cyclic monoadducts were not found.
View Article and Find Full Text PDFThe monoadducts (4a-d) of thianthrene cation radical perchlorate (1a) and isobutene, 2-methylbutene, 2-methyl-2-butene, and 2-methylpentene decompose spontaneously in acetonitrile (MeCN) solution, with the formation of thianthrene (Th). Decomposition of 4a (1,2-(5,10-thianthreniumdiyl)-2-methylpropane diperchlorate) and 4a', the corresponding dihexafluorophosphate, was studied in depth and extensively with (1)H and (13)C NMR spectroscopy. Decomposition of 4a was found to involve the solvent itself as well as water in the solvent, remaining from incomplete drying, and gave, apart from Th, successively, the perchlorate salts of 2,4,4-trimethyl-2-oxazoline (6) and 2-amino-2-methylpropyl acetate (7).
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2003
Osteoblasts are continually recruited from stem cell pools to maintain bone. Although their immediate precursor is a plastic-adherent mesenchymal stem cell able to generate tissues other than bone, increasing evidence suggests the existence of a more primitive cell that can differentiate to both hematopoietic and mesenchymal cells. We show here that the "side population" (SP) of marrow stem cells, defined by their ability to rapidly expel a DNA-binding dye and to regenerate the hematopoietic compartment, can differentiate to osteoblasts through a mesenchymal intermediate.
View Article and Find Full Text PDFPhenoxathiin cation radical perchlorate (PO.+ClO4(-)) added stereospecifically to cyclopentene, cyclohexene, cycloheptene, and 1,5-cyclooctadiene to give 1,2-bis(5-phenoxathiiniumyl)cycloalkane diperchlorates (4-7) in good yield. The diaxial configuration of the PO+ groups was confirmed with X-ray crystallography.
View Article and Find Full Text PDFWe reported recently that overexpression of neurotrophin-3 (NT-3) by motoneurons in the spinal cord of rats will induce sprouting of corticospinal tract (CST) axons (Zhou et al. [2003] J. Neurosci.
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