Search Results
Results 401 - 450 of 1176
< 4 5 6 7 8 9 10 11 12 13 14 >
Frank T C - - 2003
Cell death is a critical component of normal nervous system development; too little or too much results in abnormal development and function of the nervous system. The leaner mouse exhibits excessive, abnormal cerebellar granule cell and Purkinje cell death during postnatal development, which is a consequence of a mutated calcium ...
Bishop Georgia A - - 2002
Corticotropin-releasing factor (CRF), present in climbing and mossy fiber afferents to the adult mouse cerebellum, acts as a neuromodulator to enhance the spontaneous and amino-acid-induced firing rate of Purkinje cells. CRF also is present during development of the mouse cerebellum, at ages that precede synaptogenesis, which suggests that it may ...
Hu Xitang - - 2002
OBJECTIVE: To investigate the effects of Ginsenoside Rb(1) on the proliferation of Schwann cells in culture. METHODS: Applying MTT assay and Thymidine incorporation assay, the effects of Ginsenoside Rb(1) on the proliferation of Schwann cells isolated from the sciatic nerve of adult rat were studied. RESULTS: Ginsenoside Rb(1) (10 microg/ml) ...
Stangel Martin - - 2002
Demyelination is the pathological hallmark of multiple sclerosis (MS) lesions. The concept of remyelination has gained acceptance in recent years, but naturally occurring remyelination is incomplete. To improve repair processes, a number of strategies have been explored experimentally and clinical trials are being carried out. In principle, remyelination can be ...
Fernandez Rosario - - 2002
It is well established that forskolin-induced elevation of cAMP results in activation of DNA synthesis in Schwann cell cultures. This promitotic response is partially mediated by the Cdk2, which is required for the transition from the G1 to the S phase of the cell cycle. In the present study, we ...
Maccarrone Mauro - - 2002
Anandamide (N-arachidonoylethanolamine, AEA) is an endogenous lipid that binds to cannabinoid receptors in the central nervous system and in peripheral cells. Quantitative analysis of AEA is generally based on the normalization to the fresh weight of the samples. Here, we show that the normalization procedure of AEA content is such ...
Korsisaari Nina - - 2002
The mammalian Mat1 protein has been implicated in cell cycle regulation as part of the Cdk activating kinase (CAK), and in regulation of transcription as a subunit of transcription factor TFIIH. To address the role of Mat1 in vivo, we have used a Cre/loxP system to conditionally ablate Mat1 in ...
Benmessahel Y - - 2002
In steroidogenic cells the steroidogenic acute regulatory (StAR) protein plays a key role in the transport of cholesterol to the inner mitochondrial membrane, where the first step of steroidogenesis, the conversion of cholesterol to pregnenolone, takes place. cAMP is a known positive regulator of StAR gene expression and steroid biosynthesis ...
Huttenbach Yve - - 2002
BACKGROUND: The rare desmoplastic and spindle cell variants of malignant melanoma exhibit histological and biochemical features suggestive of early Schwann cell differentiation. These features include a spindle-shaped morphology, neurotropism, and the expression of the low affinity nerve growth factor receptor (p75NGFR). METHODS: We evaluated by immunohistochemistry (using formalin-fixed, paraffin-embedded tissues) ...
Jensen Patricia - - 2002
Granule cell precursors in the external germinal layer (EGL) of the cerebellum have been proposed to be a major player in the migration and positioning of Purkinje cells through the expression of the Netrin-like receptor Unc5h3 and the extracellular matrix molecule Reelin. To explore the role of the EGL on ...
Ghazvini Merhnaz - - 2002
While an important role for the POU domain transcription factor Oct-6 in the developing peripheral nerve has been well established, studies into its exact role in nerve development and regeneration have been hampered by the high mortality rate of newborn Oct-6 mutant animals. In this study we have generated a ...
Hai Mehreen - - 2002
Primary and immortalized cultured Schwann cells are commonly utilized in analyses of myelin gene promoters, but few lines are well-characterized in terms of their endogenous expression of myelin genes. This is particularly significant in that cultured Schwann cells typically do not express myelin genes at levels comparable to those observed ...
Matsuoka Masato - - 2002
Vomeronasal neurons undergo continuous neurogenesis during development and after neuronal injury. We used immunocytochemical methods to compare different stages of the vomeronasal organ development to those of regeneration following vomeronasal nerve transection. At E15 and at 6 to 10 days after injury, nestin-positive cells were observed throughout the sensory epithelium. ...
Chuah Meng Inn - - 2002
Ensheathing cells are the glial cells that envelop olfactory axons as they course from the olfactory epithelium to the bulb. They are derived from the olfactory placode and differ from the typical glia in terms of sharing the phenotypes of both astrocytes and Schwann cells. The aims of this study ...
Seiwa Chika - - 2002
The shiverer mutant mouse is an autosomal recessive mutant characterized by incomplete myelin sheath formation in the central nervous system (CNS). Such mice contain a deletion in the MBP gene, do not produce MBP proteins, and have little or no compact myelin in the CNS. To investigate the myelin sheath ...
Kimura-Kuroda Junko - - 2002
Using a well-defined medium with insulin, transferrin and selenium but without serum and albumin, we quantitatively determined the effect of thyroid hormones on the development of Purkinje cells in mouse cerebellar monolayer cultures. Addition of a thyroid hormone, T3 or T4, to the serum-free medium resulted in a highly elaborate ...
Pace Virgilio - - 2002
We investigated, morphologically and immunohistochemically, 74 medullary adrenal tumors, including 64 pheochromocytomas (14 malignant and 50 benign), 9 ganglioneuromas, and 1 malignant schwannoma. The tumors were detected in 2-year-old Wistar and Sprague-Dawley rats from carcinogenicity studies. Morphologically, benign pheochromocytomas were characterized by monomorphic, small, basophilic cells with almost absence of ...
Leimeroth Rainer - - 2002
Many steps of peripheral glia development appear to be regulated by neuregulin1 (NRG1) signaling but the exact roles of the different NRG1 isoforms in these processes remain to be determined. While glial growth factor 2 (GGF2), a NRG1 type II isoform, is able to induce a satellite glial fate in ...
Winseck Adam K - - 2002
The present study uses the embryonic chick to examine in vivo the mechanisms and regulation of Schwann cell programmed cell death (PCD) in spinal and cranial peripheral nerves. Schwann cells are highly dependent on the presence of axons for survival because the in ovo administration of NMDA, which excitotoxically eliminates ...
Huang Tao - - 2002
OBJECTIVE: To investigate whether Schwann cells can secrete macrophage migration inhibitory factor (MIF) after peripheral nerve injury. METHODS: Two kinds of infant rat Schwann cells(which were derived from intact and injured nerves respectively) were cultured in 10% newborn calf serum (NCS) DMEM/F12 medium for 72 h. Then the level of ...
Shen Jin-Song - - 2002
The twitcher mouse is a murine model of human globoid cell leukodystrophy (GLD; Krabbe disease) caused by a genetic defect in the activity of galactosylceramidase (GALC). An accumulation of cytotoxic metabolite, galactosylsphingosine (psychosine), in myelin forming cells (oligodendrocytes and Schwann cells) of the twitcher mouse as well as patients with ...
Mikol Daniel D - - 2002
The caveolins are a family of related proteins that form the structural framework of caveolae. They have been implicated in the regulation of signal transduction, cell cycle control, and cellular transport processes, particularly cholesterol trafficking. Caveolin-1 is expressed by a variety of cell types, including Schwann cells, although its expression ...
Karam Sana D - - 2002
The Purkinje cells of both the adult and the developing cerebellar cortex are organized into parasagittal stripes or 'segments' expressing a variety of biochemical markers. We show that in the developing mouse cerebellar cortex, members of the Eph receptor gene family are expressed in mediolaterally alternating Purkinje cell segments. Since ...
Lu Jike - - 2002
STUDY DESIGN: The literature concerning the potential use of olfactory ensheathing cells for repairing damaged spinal cord was reviewed. OBJECTIVE: To engender a better understanding of the role that olfactory ensheathing cells play in spinal cord regeneration. SUMMARY OF BACKGROUND DATA: Intraspinal transplants (e.g., fetal neuronal cells, progenitor stem cells, ...
Sakai Koichiro - - 2002
Paraneoplastic cerebellar degeneration-associated antigen PCD17/cdr2 is a neuronal protein expressed predominantly in the cytoplasm of cerebellar Purkinje cells. The biological activities of this protein are not known; however, the presence of a leucine zipper motif in its amino acid sequence suggests that this protein might interact with other proteins harboring ...
Jessen K R - - 2002
While the signals that direct neural crest cells to choose the glial lineage and generate Schwann cell precursors are still obscure, studies both in vivo and in vitro indicate that the survival and differentiation of these cells to form Schwann cells is regulated by at least two signals, neuregulin-1 and ...
Morte Beatriz - - 2002
Thyroid hormone (T3) controls critical aspects of cerebellar development, such as migration of postmitotic granule cells and terminal differentiation of Purkinje cells. T3 acts through nuclear receptors (TR) of two types, TRalpha1 and TRbeta, that either repress or activate gene expression. We have analyzed the cerebellar structure of developing mice ...
Dezawa Mari - - 2002
In contrast to the peripheral nervous system (PNS), little structural and functional regeneration of the central nervous system (CNS) occurs spontaneously following injury in adult mammals. The inability of the CNS to regenerate is mainly attributed to its own inhibitorial environment such as glial scar formation and the myelin sheath ...
Atanasoski Suzana - - 2002
Overexpression of PMP22 is responsible for the most common form of inherited neuropathy, Charcot-Marie-Tooth disease (CMT) type 1A. The PMP22-transgenic rat (CMT rat) is an animal model of CMT1A, and its peripheral nerves show the characteristic features of ongoing demyelination and remyelination that is also seen in CMT1A patients. Since ...
Lobsiger Christian S - - 2002
Schwann cells are the major glial population of the vertebrate peripheral nervous system. In the adult, they build a protecting sheath around neuronal processes and myelinate large-caliber axons. Already early in development, Schwann cells and neurons establish close contacts. Later development and the maintenance of peripheral nerves are crucially dependent ...
Wu Sufan - - 2002
Here we report a novel method of supplying cultured neurosphere cells to the injured spinal cord, by injection of cells into the cerebrospinal fluid (CSF) through the fourth ventricle or cisterna magna. Hippocampus-derived neurosphere cells, isolated from a transgenic rat fetus expressing green fluorescent protein, were transplanted into the CSF ...
Yang Huaitao - - 2002
The Disabled-1 protein in mouse is known to be an intercellular signaling component of the Reelin molecular pathway that subserves neuronal migration in several structures in the brain and spinal cord. The scrambler mutant mouse, which is phenotypically identical to the reeler mouse, is due to a mutation in the ...
Light K E - - 2002
The present study was designed to evaluate the time course and manner of Purkinje cell death following a single ethanol dose delivered intragastrically on postnatal day (PN) 4 to rat pups. Analysis included immunolabeling of Purkinje cells with antibody specific for calbindin D28k and counting of Purkinje cells in each ...
Sekita-Krzak Joanna - - 2002
The purpose of this research was an assessment of neuroprotective effect of ACTH (4-9) in degenerative changes of nerve cells induced by dexamethasone. Experiments were led on Albino-Swiss mouse males. We examine morphological changes of neurons in the dorsal hippocampus in slides stained with cresyl violet and we performed quantitative ...
Atanasoski S - - 2001
Neurons regulate Schwann cell proliferation, but little is known about the molecular basis of this interaction. We have examined the possibility that cyclin D1 is a key regulator of the cell cycle in Schwann cells. Myelinating Schwann cells express cyclin D1 in the perinuclear region, but after axons are severed, ...
Matsumoto M - - 2001
Intracellular calcium release in response to bath-applied quisqualate or caffeine was examined in cerebellar primary cultures of type-1-inositol-1,4,5-trisphosphate-receptor (IP3R1)- deficient mice. Under [Ca2+]o-free conditions, calcium release in response to 10 microM quisqualate was significantly reduced in Purkinje cells, but was unaffected in granule cells, suggesting that different subtypes of IP3 ...
Hagge, Deanna Alisa
Globally, millions of leprosy patients suffer irreversible peripheral nerve damage resulting in blindness or other disabilities as a consequence of Mycobacterium leprae infection. Schwann cells, the neural target of M. leprae, have a central role in leprosy histopathology including axonotrophy, altered myelin architecture and demyelination. The mechanisms of nerve damage ...
Parkinson D B - - 2001
In some situations, cell death in the nervous system is controlled by an interplay between survival factors and negative survival signals that actively induce apoptosis. The present work indicates that the survival of Schwann cells is regulated by such a dual mechanism involving the negative survival signal transforming growth factor ...
Sancho S - - 2001
Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by an increased dosage of the peripheral myelin protein 22 (PMP22) gene or by point mutations affecting the same gene. Based on in vitro data, PMP22 might be involved, besides in its proven role in the regulation of myelination and myelin maintenance, in ...
Benn T - - 2001
Oligodendrocytes and Schwann cells are the glia principally responsible for the synthesis and maintenance of myelin. Damage may occur to these cells in a number of conditions, but perhaps the most studied are the idiopathic inflammatory demyelinating diseases, multiple sclerosis in the CNS, and Guillain-Barré syndrome and its variants in ...
Schumacher M - - 2001
Progesterone is synthesized in the nervous system by neurons and glial cells. Because of their simple structure, plasticity and capacity of regeneration, peripheral nerves are particularly well suited for studying the biosynthesis, mechanisms of action and effects of the hormone. Schwann cells, the myelinating glial cells in the peripheral nervous ...
Huelsing, D. J.
Regional differences in the restitution of action potential duration may be arrhythmogenic. Though such a difference exists at the Purkinje-ventricular interface, restitution kinetics have not yet been defined between coupled Purkinje and ventricular cells, Thus, the purpose of this study was to determine the effects of coupling on restitution in ...
Okubo Y - - 2001
IP(3) signaling in Purkinje cells is involved in the regulation of cell functions including LTD. We have used a GFP-tagged pleckstrin homology domain to visualize IP(3) dynamics in Purkinje cells. Surprisingly, IP(3) production was observed in response not only to mGluR activation, but also to AMPA receptor activation in Purkinje ...
Vogel M W - - 2001
+/Lc Purkinje cells degenerate postnatally because of a gain-of-function mutation in the delta2 glutamate receptor (Grid2) that causes a constitutive Na+ current leak. The effect of the resulting chronic depolarization on Purkinje cell metabolism was investigated by measuring levels of cytochrome oxidase (COX) activity in Purkinje cell dendrites using quantitative ...
Bale S D - - 2001
Immunohistochemical and ultrastructural techniques were used to study sequelae of nerve injury in the pulmonate snail Melampus bidentatus. Either pedal or tentacle nerves were crushed, severing all axons, and recovery was monitored over 15 days. The axons regenerated from the segment attached to the soma, with no evidence of fusion ...
Lobsiger C S - - 2001
Dramatic progress has been made over recent years toward the elucidation of the mechanisms regulating lineage determination and cell survival in the developing peripheral nervous system. However, our understanding of Schwann cell development is limited. This is partly due to the difficulties in culturing primary Schwann cell precursor cells, the ...
Wang J - - 2001
The Survival of Motor Neurons (SMN) is the disease gene of spinal muscular atrophy. We have previously established a genetic system based on the chicken pre-B cell line DT40, in which expression of SMN protein is regulated by tetracycline, to study the function of SMN in vivo. Depletion of SMN ...
Barnett S C - - 2001
The olfactory ensheathing cell (OEC) is a unique glial cell able to support neurite outgrowth in the CNS throughout life. The OEC has been described as having both Schwann cell-like and astrocyte-like characteristics. The purpose of this study was to compare gap junctional communication and connexin (Cx) expression in cultured ...
Itoh M - - 2001
RGS8 was originally identified as an RGS protein specifically expressed in neuronally differentiated P19 cells. We generated a polyclonal antibody specific to rat RGS8 using a synthetic peptide. When nonneural cells (DDT1MF2, CHO, and NIH3T3) transfected with rat RGS8 cDNA were immuno-stained with this antibody, the RGS8 protein was mainly ...
Sugimoto Y - - 2001
Oligodendrocyte precursors are produced in restricted foci of the germinative neuroepithelium in embryo brains and migrate to their sites of function, while astrocytes are produced in a wider area in the neuroepithelium. We investigated the guidance mechanisms of glial precursor (GP) cell migration in the optic nerve. GP cell migration ...
< 4 5 6 7 8 9 10 11 12 13 14 >