Int J Environ Res Public Health
December 2021
Poor freshwater beach quality, measured by () levels, poses a risk of recreational water illness. This study linked environmental data to geometric means collected at 18 beaches in Toronto (2008-2019) and the Niagara Region (2011-2019) to examine the environmental predictors of . We developed region-specific models using mixed effects models to examine as a continuous variable and recommended thresholds of concentration (100 CFU/100 mL and 200 CFU/100 mL).
View Article and Find Full Text PDFObjective: Vascular restenosis remains a major obstacle to long-term success after vascular intervention. Circulating progenitor cells have been implicated in restenosis, and yet it has remained unclear if these cells, particularly nonendothelial progenitors, have an active role in this pathologic process. We hypothesized that circulating CD34(+)/c-kit(+) progenitors would increase after vascular injury, mirrored by changes in the injury signal, stromal cell-derived factor 1α (sdf1α).
View Article and Find Full Text PDFBiologic scaffolds composed of extracellular matrix (ECM) are commonly used repair devices in preclinical and clinical settings; however the use of these scaffolds for peripheral and central nervous system (CNS) repair has been limited. Biologic scaffolds developed from brain and spinal cord tissue have recently been described, yet the conformation of the harvested ECM limits therapeutic utility. An injectable CNS-ECM derived hydrogel capable of in vivo polymerization and conformation to irregular lesion geometries may aid in tissue reconstruction efforts following complex neurologic trauma.
View Article and Find Full Text PDFPioneering clinical stem cell research is being performed in the horse, a recipient of cutting edge veterinary medicine as well as a unique animal model, paving the way for human medical applications. Although demonstrable progress has been made on the clinical front, in vitro characterization of equine stem cells is still in comparatively early stages. To translate the promising results of clinical stem cell therapy in the horse, advances must be made in the characterization of equine stem cells.
View Article and Find Full Text PDFBiologic scaffolds composed of extracellular matrix (ECM) have been used successfully in preclinical models and humans for constructive remodeling of functional, site-appropriate tissue after injury. The mechanisms underlying ECM-mediated constructive remodeling are not completely understood, but scaffold degradation and site-directed recruitment of progenitor cells are thought to play critical roles. Previous studies have identified a cryptic peptide derived from the C-terminal telopeptide of collagen IIIα that has chemotactic activity for progenitor cells.
View Article and Find Full Text PDFBinding of the HIV envelope to the chemokine coreceptors triggers membrane fusion and signal transduction. The fusion process has been well characterized, yet the role of coreceptor signaling remains elusive. Here, we describe a critical function of the chemokine coreceptor signaling in facilitating HIV infection of resting CD4 T cells.
View Article and Find Full Text PDFRetroviruses require integration of their RNA genomes for both stability and productive viral replication. In HIV infection of non-dividing, resting CD4 T cells, where integration is greatly impeded, the reverse transcribed HIV DNA has limited biological activity and a short half-life. In metabolically active and proliferating T cells, unintegrated DNA rapidly diminishes with cell division.
View Article and Find Full Text PDFVis Neurosci
March 2005
Why photoreceptors turn over a portion of their photoreceptive membrane daily is not clear; however, failure to do so properly leads to retinal degeneration in vertebrates and invertebrates. Little is known about the molecular mechanisms that regulate shedding and renewal of photoreceptive membrane. Photoreceptive cells in the lateral eye of the horseshoe crab Limulus turn over their photoreceptive membrane (rhabdom) in brief, synchronous burst in response to dawn each morning.
View Article and Find Full Text PDFBrain Res Dev Brain Res
November 2004
Neural stem cells and neural progenitors (NSCs/NPs) are capable of self-renewal and can give rise to both neurons and glia. Such cells have been isolated from the embryonic brain and immobilized in three dimensional collagen gels. The collagen-entrapped NSCs/NPs recapitulate CNS stem cell development and form functional synapses and neuronal circuits.
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