Search results for "Movement"
showing 10 items of 2021 documents
Selectivity of pharmacological tools: implications for use in cell physiology. A Review in the Theme: Cell Signaling: Proteins, Pathways and Mechanis…
2014
Pharmacological inhibitors are frequently used to identify the receptors, receptor subtypes, and associated signaling pathways involved in physiological cell responses. Based on the effects of such inhibitors conclusions are drawn about the involvement of their assumed target or lack thereof. While such inhibitors can be useful tools for a better physiological understanding, their uncritical use can lead to incorrect conclusions. This article reviews the concept of inhibitor selectivity and its implication for cell physiology. Specifically, we discuss the implications of using inhibitor vs. activator approaches, issues of direct vs. indirect pathway modulation, implications of inverse agoni…
In Vivo Imaging of Partially Reversible Th17 Cell-Induced Neuronal Dysfunction in the Course of Encephalomyelitis
2010
SummaryNeuronal damage in autoimmune neuroinflammation is the correlate for long-term disability in multiple sclerosis (MS) patients. Here, we investigated the role of immune cells in neuronal damage processes in animal models of MS by monitoring experimental autoimmune encephalomyelitis (EAE) by using two-photon microscopy of living anaesthetized mice. In the brainstem, we detected sustained interaction between immune and neuronal cells, particularly during disease peak. Direct interaction of myelin oligodendrocyte glycoprotein (MOG)-specific Th17 and neuronal cells in demyelinating lesions was associated with extensive axonal damage. By combining confocal, electron, and intravital microsc…
Growth of human cells on polyethersulfone (PES) hollow fiber membranes.
2004
A novel material of porous hollow fibers made of polyethersulfone (PES) was examined for its ability to support the growth of human cells. This material was made in the absence of solvents and had pore diameters smaller than 100 microm. Human cell lines of different tissue and cell types (endothelial, epithelial, fibroblast, glial, keratinocyte, osteoblast) were investigated for adherence, growth, spread and survival on PES by confocal laser microscopy after staining of the cells with Calcein-AM. Endothelial cell attachment and growth required pre-coating PES with either fibronectin or gelatin. The other cell types exhibited little difference in growth, spread or survival on coated or uncoa…
Growth of human cells on a non-woven silk fibroin net: a potential for use in tissue engineering.
2003
We have examined a novel biomaterial consisting of a non-woven fibroin net produced from silk (Bombyx mori) cocoons for its ability to support the growth of human cells. Various human cells of different tissue and cell types (endothelial, epithelial, fibroblast, glial, keratinocyte, osteoblast) were examined for adherence and growth on the nets by confocal laser microscopy after staining of the cells with calcein-AM and by electron microscopy. All the cells readily adhered and spread over the individual fibers of the nets. Most of the cells were able to grow and survive on the nets for at least 7 weeks and growth not only covered the individual fibers of the net but generally bridged the ga…
Primary Neural Precursors and Intermitotic Nuclear Migration in the Ventricular Zone of Adult Canaries
1998
New neurons continue to be born in the ventricular zone (VZ) of the lateral ventricles in the brain of adult birds. On the basis of serial section reconstruction and electron microscopy, we determined that the VZ of the adult canary brain is composed of three main cell types (A, B, and E). Type A cells were never found in contact with the ventricle and had microtubule-rich processes typical of young migrating neurons. Type B cells were organized as a pseudostratified epithelium, all contacted the ventricle, and most had a characteristic single cilium. Type E cells, also in contact with ventricle, were ultrastructurally similar to the mammalian multiciliated ependymal cells. After six inject…
High expression of QSOX1 reduces tumorogenesis, and is associated with a better outcome for breast cancer patients.
2012
International audience; ABSTRACT: INTRODUCTION: The gene quiescin/sulfhydryl oxidase 1, QSOX1, encodes an enzyme directed to the secretory pathway and excreted into the extracellular space. QSOX1 participates in the folding and stability of proteins and thus could regulate the biological activity of its substrates in the secretory pathway and/or outside the cell. The involvement of QSOX1 in oncogenesis has been studied primarily in terms of its differential expression in systemic studies. QSOX1 is overexpressed in prostate cancers and in pancreatic adenocarcinoma. In contrast, QSOX1 gene expression is repressed in endothelial tumors. In the present study, we investigated the role of QSOX1 i…
Role of adenylate kinase type 7 expression on cilia motility: possible link in primary ciliary dyskinesia.
2010
Background Adenylate kinase 7 (AK7) mediates the reaction 2ADP ↔ ATP + AMP, providing energy for the beating of cilia. A study recently showed that AK7 expression may be correlated with the primary ciliary dyskinesia (PCD) phenotype in mice. In this study, we characterized AK7 expression in vitro in an air–liquid interface (ALI) model and in middle nasal turbinate biopsy specimens from a cohort of patients with PCD to elucidate whether AK7 expression is correlated with ciliary malfunction. Methods AK7 expression was measured by real-time reverse-transcription polymerase chain reaction and Western blotting. In vitro differentiated nasal human epithelial cell siRNA experiments were performed …
EGF converts transit-amplifying neurogenic precursors in the adult brain into multipotent stem cells.
2002
AbstractNeural stem cells in the subventricular zone (SVZ) continue to generate new neurons in the adult brain. SVZ cells exposed to EGF in culture grow to form neurospheres that are multipotent and self-renewing. We show here that the majority of these EGF-responsive cells are not derived from relatively quiescent stem cells in vivo, but from the highly mitotic, Dlx2+, transit-amplifying C cells. When exposed to EGF, C cells downregulate Dlx2, arrest neuronal production, and become highly proliferative and invasive. Killing Dlx2+ cells dramatically reduces the in vivo response to EGF and neurosphere formation in vitro. Furthermore, purified C cells are 53-fold enriched for neurosphere gene…
Genetic Cell Ablation Reveals Clusters of Local Self-Renewing Microglia in the Mammalian Central Nervous System
2015
SummaryDuring early embryogenesis, microglia arise from yolk sac progenitors that populate the developing central nervous system (CNS), but how the tissue-resident macrophages are maintained throughout the organism’s lifespan still remains unclear. Here, we describe a system that allows specific, conditional ablation of microglia in adult mice. We found that the microglial compartment was reconstituted within 1 week of depletion. Microglia repopulation relied on CNS-resident cells, independent from bone-marrow-derived precursors. During repopulation, microglia formed clusters of highly proliferative cells that migrated apart once steady state was achieved. Proliferating microglia expressed …
Spatio-temporal pattern of cells expressing the clock genes period and timeless and the lineages of period expressing neurons in the embryonic CNS of…
2010
The initial steps towards the generation of cell diversity in the central nervous system of the fruitfly Drosophila melanogaster take place during early phases of embryonic development when a stereotypic population of neural progenitor cells (neuroblasts and midline precursors) is formed in a precise spatial and temporal pattern, and subsequently expresses a particular sequence of genes. The clarification of the positional, temporal and molecular features of the individual progenitor cells in the nerve cord and brain as well as of their specific types of neuronal and/or glial progeny cells forms an essential basis to understand the mechanisms controlling their development. The present study…