Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Neurofilament

  • phosphorylated neurofilament

  • Terms modified by Neurofilament

  • neurofilament protein

  • Selected Abstracts

    Transport of neurofilaments in growing axons requires microtubules but not actin filaments

    Franto Francis
    Abstract Neurofilament (NF) polymers are conveyed from cell body to axon tip by slow axonal transport, and disruption of this process is implicated in several neuronal pathologies. This movement occurs in both anterograde and retrograde directions and is characterized by relatively rapid but brief movements of neurofilaments, interrupted by prolonged pauses. The present studies combine pharmacologic treatments that target actin filaments or microtubules with imaging of NF polymer transport in living axons to examine the dependence of neurofilament transport on these cytoskeletal systems. The heavy NF subunit tagged with green fluorescent protein was expressed in cultured sympathetic neurons to visualize NF transport. Depletion of axonal actin filaments by treatment with 5 ,M latrunculin for 6 hr had no detectable effect on directionality or transport rate of NFs, but frequency of movement events was reduced from 1/3.1 min of imaging time to 1/4.9 min. Depolymerization of axonal microtubules using either 5 ,M vinblastine for 3 hr or 5 ,g/ml nocodazole for 4,6 hr profoundly suppressed neurofilament transport. In 92% of treated neurons, NF transport was undetected. These observations indicate that actin filaments are not required for neurofilament transport, although they may have subtle effects on neurofilament movements. In contrast, axonal transport of NFs requires microtubules, suggesting that anterograde and retrograde NF transport is powered by microtubule-based motors. © 2005 Wiley-Liss, Inc. [source]

    Neutralization of the membrane protein Nogo-A enhances growth and reactive sprouting in established organotypic hippocampal slice cultures

    Luis M. Craveiro
    Abstract The reduced ability of central axons to regenerate after injury is significantly influenced by the presence of several molecules that inhibit axonal growth. Nogo-A is one of the most studied and most potent of the myelin-associated growth inhibitory molecules. Its neutralization, as well as interference with its signalling, allows for enhanced axonal sprouting and growth following injury. Using differentiated rat organotypic hippocampal slice cultures treated for 5 days with either of two different function-blocking anti-Nogo-A antibodies, we show an increase in CA3 fibre regeneration after lesion. In intact slices, 5 days of anti-Nogo-A antibody treatment led to increased sprouting of intact CA3 fibres that are positive for neurofilament 68. A transcriptomic approach confirmed the occurrence of a growth response on the molecular level upon Nogo-A neutralization in intact cultures. Our results demonstrate that Nogo-A neutralization for 5 days is sufficient for the induction of growth in mature CNS tissue without the prerequisite of an injury. Nogo-A may therefore act as a tonic growth suppressor/stabilizer in the adult intact hippocampus. [source]

    Characterization of TROY-expressing cells in the developing and postnatal CNS: the possible role in neuronal and glial cell development

    Tomoko Hisaoka
    Abstract A member of the tumor necrosis factor receptor superfamily, TROY, is expressed in the CNS of embryonic and adult mice. In the present study, we characterized TROY-expressing cells in the embryonic and postnatal forebrain. In the early embryonic forebrain, TROY was highly expressed in nestin-positive neuroepithelial cells and radial glial cells, but not in microtubule-associated protein 2-positive postmitotic neurons. During the late embryonic and postnatal development, expression of TROY was observed in radial glial cells and astrocytes, whereas its expression was not detected in neuronal lineage cells. In addition, TROY was exclusively expressed in Musashi-1-positive multipotent/glial progenitors in the postnatal subventricular zone. To investigate the functions of TROY in neural development, we overexpressed TROY in PC12 cells and established stably expressing cell clones. As expected, the signals from overexpressed TROY were constitutively transduced via the activation of the nuclear factor-,B and the c-Jun N-terminal kinase pathways in such clones. In addition, upregulation of negative basic helix,loop,helix transcription factors, HES-5 and Id2 proteins, was observed in the TROY-overexpressing clones. Interestingly, the overexpression of TROY in PC12 cells strongly inhibited nerve growth factor-induced neurite outgrowth with reduction of some markers of differentiated neurons, such as neurofilament 150 kDa and neuron-specific ,-tubulin. These findings suggest that the signaling from TROY regulates neuronal differentiation at least in part. [source]

    NGF and GDNF ameliorate the increase in ATF3 expression which occurs in dorsal root ganglion cells in response to peripheral nerve injury

    Sharon Averill
    Abstract Activating transcription factor-3 (ATF3) is a member of the ATF/CREB transcription factor superfamily and is induced in dorsal root ganglion (DRG) cells after nerve injury. In order to study the regulation of ATF3, we have examined the effect of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) on ATF3 expression. In untreated rats, sciatic nerve transection induced ATF3 immunoreactivity in 82% of L4 DRG cells at 14 days after axotomy. Intrathecal delivery of NGF or GDNF for 2 weeks commencing immediately after injury reduced the ATF3 expression to 35 and 23% of DRG cells, respectively. Cell size analysis indicated that NGF had protected a population of mainly small- to medium-sized cells, but that the GDNF had protected a population of both small and large cells. This effect was confirmed by double labelling for P2X3, CGRP and 200 kDa neurofilament, markers for small peptide-poor cells, peptide-rich cells and large cells, respectively. Thus GDNF reduced the percentage of ATF3-immunoreactive P2X3 cells from 70 to 4%, and the percentage of ATF3-immunoreactive neurofilament cells from 63 to 24%. NGF was less effective than GDNF in reducing ATF3 expression in these cell types, but reduced the percentage of ATF3-immunoreactive CGRP cells from 10% to <,1%. These results show that ATF3 expression in specific populations of DRG cells can be modulated by exogenous supplementation of specific trophic factors, and suggest that ATF3 expression may normally be induced by the loss of target-derived NGF and GDNF. [source]

    Cutaneous sclerosing perineurioma of the digit

    Toshitsugu Nakamura MD
    An 11-year-old Japanese girl noticed a small nodule, with mild tenderness, on the right index finger 5 years before visiting our outpatient clinic. She had no familial history of neurofibromatosis or past history of traumatic injury at the site of the tumor. Physical examination revealed a slightly elevated, subcutaneous, nodular tumor in the volar aspect between the proximal and distal interphalangeal joints of the digit (Fig. 1A). By magnetic resonance imaging examination, the tumor showed low density on both T1- and T2-weighted images, and was located just adjacent to the tendon with no invasive signs. The tumor was extirpated; at operation, it was well circumscribed and mobile without adhesion to adjacent tendon or nerve, and was easily removed. Figure 1. (a) Slightly elevated subcutaneous tumor (arrow) on the volar aspect of the right index finger. (b) gross appearance of the extirpated tumor, showing a well-circumscribed, whitish solid nodule Grossly, the tumor was a well-circumscribed, firm nodule (10 mm × 8 mm × 5 mm in size) (Fig. 1B). The cut surface was whitish, homogeneous, and solid without cystic lesions. Histologically, it was an unencapsulated, paucicellular dense, fibrous nodule with a concentric circular arrangement of collagen bundles (Fig. 2A). Amongst the fibrous bundles, a small number of ovoid/epithelioid or plump spindle cells were arranged in a corded, trabecular, or whorled (onion bulb-like) pattern (Fig. 2B); a storiform pattern was not noted. These cells were relatively uniform and had a somewhat elongated, slightly hyperchromatic nucleus with fine granular chromatin. Neither nuclear pleomorphism nor multinucleated cells were evident, and necrosis and mitotic figures were not observed. Periodic acid,Schiff (PAS) stain after diastase digestion highlighted the corded or whorled pattern of the tumor cells by encasing them. For immunohistochemical examination, formalin-fixed, paraffin-embedded serial tissue sections were stained by a labeled streptavidin,biotin method. The tumor cells were positive for vimentin and epithelial membrane antigen (EMA) (Fig. 3A), and negative for pan-cytokeratin, carcinoembryonic antigen (CEA), CD34, ,-smooth muscle actin, desmin, and CD68. Type IV collagen and laminin (Fig. 3B) were detected along the cords or whorls of the tumor cells, similar to the staining pattern of the diastase-PAS reaction. Schwann cells and axonal components, immunoreactive for S100 protein and neurofilament, respectively, were focally detected just adjacent to the cords or whorls, although the tumor cells per se did not express these proteins. Consequently, the tumor was found to be perineurial in origin and was diagnosed as cutaneous sclerosing perineurioma. Figure 2. (a) Low-power view of the tumor, showing an unencapsulated, paucicellular, dense, fibrous nodule with a concentric circular arrangement of collagen bundles (hematoxylin and eosin stain: original magnification, ×15). (b) Higher magnification of the tumor, showing ovoid or epithelioid cells arranged in cords or whorls in the abundant collagen bundles (hematoxylin and eosin stain: original magnification, ×150) Figure 3. Immunohistochemical profiles of the tumor. The tumor cells are positive for epithelial membrane antigen (a) and are surrounded by laminin (b) (original magnification, ×150) [source]

    Development of axonal pathways in the human fetal fronto-limbic brain: histochemical characterization and diffusion tensor imaging

    JOURNAL OF ANATOMY, Issue 4 2010
    Lana Vasung
    Abstract The development of cortical axonal pathways in the human brain begins during the transition between the embryonic and fetal period, happens in a series of sequential events, and leads to the establishment of major long trajectories by the neonatal period. We have correlated histochemical markers (acetylcholinesterase (AChE) histochemistry, antibody against synaptic protein SNAP-25 (SNAP-25-immunoreactivity) and neurofilament 200) with the diffusion tensor imaging (DTI) database in order to make a reconstruction of the origin, growth pattern and termination of the pathways in the period between 8 and 34 postconceptual weeks (PCW). Histological sections revealed that the initial outgrowth and formation of joined trajectories of subcortico-frontal pathways (external capsule, cerebral stalk,internal capsule) and limbic bundles (fornix, stria terminalis, amygdaloid radiation) occur by 10 PCW. As early as 11 PCW, major afferent fibers invade the corticostriatal junction. At 13,14 PCW, axonal pathways from the thalamus and basal forebrain approach the deep moiety of the cortical plate, causing the first lamination. The period between 15 and 18 PCW is dominated by elaboration of the periventricular crossroads, sagittal strata and spread of fibers in the subplate and marginal zone. Tracing of fibers in the subplate with DTI is unsuccessful due to the isotropy of this zone. Penetration of the cortical plate occurs after 24,26 PCW. In conclusion, frontal axonal pathways form the periventricular crossroads, sagittal strata and ,waiting' compartments during the path-finding and penetration of the cortical plate. Histochemistry is advantageous in the demonstration of a growth pattern, whereas DTI is unique for demonstrating axonal trajectories. The complexity of fibers is the biological substrate of selective vulnerability of the fetal white matter. [source]

    Rapid loss of motor nerve terminals following hypoxia,reperfusion injury occurs via mechanisms distinct from classic Wallerian degeneration

    JOURNAL OF ANATOMY, Issue 6 2008
    Becki Baxter
    Abstract Motor nerve terminals are known to be vulnerable to a wide range of pathological stimuli. To further characterize this vulnerability, we have developed a novel model system to examine the response of mouse motor nerve terminals in ex vivo nerve/muscle preparations to 2 h hypoxia followed by 2 h reperfusion. This insult induced a rapid loss of neurofilament and synaptic vesicle protein immunoreactivity at pre-synaptic motor nerve terminals but did not appear to affect post-synaptic endplates or muscle fibres. The severity of nerve terminal loss was dependent on the age of the mouse and muscle type: in 8,12-week-old mice the predominantly fast-twitch lumbrical muscles showed an 82.5% loss, whereas the predominantly slow-twitch muscles transversus abdominis and triangularis sterni showed a 57.8% and 27.2% loss, respectively. This was contrasted with a > 97% loss in the predominantly slow-twitch muscles from 5,6-week-old mice. We have also demonstrated that nerve terminal loss occurs by a mechanism distinct from Wallerian degeneration, as the slow Wallerian degeneration (Wlds) gene did not modify the extent of nerve terminal pathology. Together, these data show that our new model of hypoxia,reperfusion injury is robust and repeatable, that it induces rapid, quantitative changes in motor nerve terminals and that it can be used to further examine the mechanisms regulating nerve terminal vulnerability in response to hypoxia,reperfusion injury. [source]

    Paranuclear dots of neurofilament reliably identify Merkel cell carcinoma

    Timothy H. McCalmont
    No abstract is available for this article. [source]

    Paranuclear dots of neurofilament reliably identify Merkel cell carcinoma

    Timothy H. McCalmont
    No abstract is available for this article. [source]

    Defective axonal transport of neurofilament proteins in neurons overexpressing peripherin

    Stéphanie Millecamps
    Abstract Peripherin is a type III neuronal intermediate filament detected in motor neuron inclusions of amyotrophic lateral sclerosis (ALS) patients. We previously reported that overexpression of peripherin provokes late-onset motor neuron dysfunction in transgenic mice. Here, we show that peripherin overexpression slows down axonal transport of neurofilament (NF) proteins, and that the transport defect precedes by several months the appearance of axonal spheroids in adult mice. Defective NF transport by peripherin up-regulation was further confirmed with dorsal root ganglia (DRG) neurons cultured from peripherin transgenic embryos. Immunofluorescence microscopy and western blotting revealed that excess peripherin provokes reduction in levels of hyperphosphorylated NF-H species in DRG neurites. Similarly the transport of a green fluorescent protein (GFP)-tagged NF-M, delivered by means of a lentiviral construct, was impaired in DRG neurites overexpressing peripherin. These results demonstrate that peripherin overexpression can cause defective transport of type IV NF proteins, a phenomenon that may account for the progressive formation of ALS-like spheroids in axons. [source]

    Rho-associated kinase (ROCK) inhibitor, Y27632, promotes neurite outgrowth in PC12 cells in the absence of NGF

    R. Nath
    Neurite extension and retraction are very important processes in the formation of neuronal networks. A strategy for fostering axonal regrowth/regeneration of injured adult neurons is attractive therapeutically for various diseases such as traumatic brain injury, stroke and Alzheimer's disease. The Rho family of small GTPases, including Rac and Cdc42 have been shown to be involved in promoting neurite outgrowth. On the other hand, activation of RhoA induces collapse of growth cone and retraction of neurites. Rho-associated kinase (ROCK) an effector molecule of RhoA, is downstream of a number of axonal outgrowth and growth cone collapse inhibition mechanisms. In the present study, we sought to identify the role of ROCK in neurite outgrowth in PC12 cells. Y27632, a specific inhibitor of ROCK, induced a robust increase in neurite outgrowth in these cells within 24,48 h as visualized by phase contrast microscopy. Staining with FITC-tubulin or phalloidin show extended neurites in PC12 cells treated with Y27632, comparable to that with 100 ng/mL of NGF. Assessment of other biochemical markers of neurite outgrowth such as GAP43, neurofilament and tyrosine hydroxylase phosphorylation further indicates that inhibition of ROCK in PC12 cells causes differentiation of these cells to a neuronal phenotype. [source]

    Mice with the deleted neurofilament of low molecular weight (Nefl) gene: 2.

    Effects on motor functions, spatial orientation
    Abstract Mice with a null mutation of the Nefl gene were compared with normal controls in tests of motor activity, equilibrium, and spatial orientation. Despite a normal capacity to ambulate, NFL ,/, mice had fewer rears in an open field, crossed fewer segments on stationary beams, and fell more frequently when suspended on a horizontal bar. In addition, the distance swum before reaching the escape platform was greater in NFL ,/, mice than in controls during acquisition of place learning in the Morris water maze at the start of training. The motor impairments were linearly correlated with increased cytochrome oxidase activity seen in cerebellum and brainstem. These results indicate that, as early as 6 months, depletion of the NFL protein is sufficient to cause mild sensorimotor dysfunctions and spatial deficits, but without overt signs of paresis. © 2005 Wiley-Liss, Inc. [source]

    Protein tyrosine phosphatase ,-deficient mice show aberrant cytoarchitecture and structural abnormalities in the central nervous system

    Karen Meathrel
    Abstract Protein tyrosine phosphatase , (PTP,) is a member of the LAR family of receptor tyrosine phosphatases and is highly expressed in the nervous system during development. PTP, is homologous to the Drosophila DLAR, which plays a key role in the targeting of axonal growth cones in flies. We have previously inactivated the Ptprs gene in mice and demonstrated stunted growth, developmental delays, and neurological and neuroendocrine defects in the PTP, null animals. Here, we mapped the expression of the lac-Z reporter gene included in the knockout cassette and surveyed the development of the CNS in these mice after birth. The strongest expression of ,-galactosidase (PTP,) was observed in the hippocampus, cerebral cortex, olfactory bulbs, and subependymal layer. Our analysis reveals hippocampal dysgenesis, reductions in the thickness of the corpus callosum and the cerebral cortex, and late expression of the growth-associated protein 43 (GAP-43) in the knockout animals. Architectural abnormalities in the brain and spinal cord were confirmed by immunoreactivity to neurofilament and glial fibrillary acidic protein (GFAP) antibodies. Several of these neural abnormalities were corrected with age, suggesting a delay in neurological development related to the knockout of the Ptprs gene. These data suggest that PTP, is likely involved in neurogenesis, axonal growth, and axonal pathfinding in the maturation of the mammalian CNS. © 2002 Wiley-Liss, Inc. [source]

    The effect of hyperbaric oxygen treatment on early regeneration of sensory axons after nerve crush in the rat

    Fajko F. Bajrovi
    Abstract The effect of hyperbaric oxygen treatment (HBO) on sensory axon regeneration was examined in the rat. The sciatic nerve was crushed in both legs. In addition, the distal stump of the sural nerve on one side was made acellular and its blood perfusion was compromised by freezing and thawing. Two experimental groups received hyperbaric exposures (2.5 ATA) to either compressed air (pO2 = 0.5 ATA) or 100% oxygen (pO2 = 2.5 ATA) 90 minutes per day for 6 days. Sensory axon regeneration in the sural nerve was thereafter assessed by the nerve pinch test and immunohistochemical reaction to neurofilament. HBO treatment increased the distances reached by the fastest regenerating sensory axons by about 15% in the distal nerve segments with preserved and with compromised blood perfusion. There was no significant difference between the rats treated with different oxygen tensions. The total number of regenerated axons in the distal sural nerve segments after a simple crush injury was not affected, whereas in the nerve segments with compromised blood perfusion treated by the higher pO2, the axon number was about 30% lower than that in the control group. It is concluded that the beneficial effect of HBO on sensory axon regeneration is not dose-dependent between 0.5 and 2.5 ATA pO2. Although the exposure to 2.5 ATA of pO2 moderately enhanced early regeneration of the fastest sensory axons, it decreased the number of regenerating axons in the injured nerves with compromised blood perfusion of the distal nerve stump. [source]

    Pigmented ependymoma with signet-ring cells and Rosenthal fibers: A rare variant of ependymoma

    NEUROPATHOLOGY, Issue 1 2010
    Yesim Ertan
    We report a rare case of ependymoma with vacuolar features, signet cells, pigmentation and numerous Rosenthal fibers arising in the fourth ventricle of a 35-year-old woman. The tumor was composed of cells with cytoplasmic vacuoles, signet cells and clear cells. The clear cells were compactly arranged resembling oligodendroglioma. Pseudovascular and ependymal rosettes were observed only in focal areas. Additionally, some tumor cells contained brown cytoplasmic pigment, which was histochemically compatible with lipofuscin and neuromelanin. On immunohistochemical examination, the tumor cells were positive for S100, glial fibrillary acidic protein and vimentin, and negative for synaptophysin, cytokeratin, neurofilament and HMB45. Epithelial membrane antigen staining showed dot-like and small vesicular reactivity. The case is presented to increase familiarity with these extraordinary variants of ependymoma. [source]

    Erythropoietin attenuates white matter damage, proinflammatory cytokine and chemokine induction in developing rat brain after intra-uterine infection

    NEUROPATHOLOGY, Issue 5 2009
    Ying Shen
    To investigate the possible ameliorating effect of recombinant human erythropoietin (rhEPO) on white matter damage, pro-inflammatory cytokine and chemokine induction in developing rat brain after intra-uterine Escherichia coli infection. E. coli was inoculated into uterine cervix of the time-pregnant rats and the control was injected with normal saline. Following maternal E. coli inoculation, the pups received a single intraperitoneal injection of rhEPO at a dose of 5000 IU/kg body weight immediately after birth. Immunohistochemical staining and Western blot analysis for 2,, 3,-cyclic nucleotide 3,-phosphodiesterase (CNPase), neurofilament (NF) and glial fibrillary acidic protein (GFAP) were performed to assess white matter damage in pup brains at post-natal day 1 (P1), P3 and P7. Pro-inflammatory cytokines and chemokines were detected by real-time quantitative RT-PCR at the mRNA levels to evaluate the inflammatory response in pup brains at P1, P3 and P7. A single dose of rhEPO treatment (5000 IU/kg body weight) attenuated white matter damage in developing rat brain after intra-uterine E. coli infection. The protein levels of CNPase and NF in pup brains at P7 significantly increased after post-natal rhEPO treatment as compared with the intra-uterine E. coli -treated group. Also, post-natal rhEPO injection markedly attenuated the intra-uterine E. coli infection-induced increases in GFAP protein expression and the mRNA levels of pro-inflammatory cytokines and chemokines. Post-natal EPO administration as a single dose may exert a neuroprotective effect on white matter damage by reducing pro-inflammatory cytokine and chemokine induction in developing rat brain after intra-uterine E. coli infection. [source]

    Autopsy case of aluminum encephalopathy

    NEUROPATHOLOGY, Issue 3 2002
    Teruo Shirabe
    We report the case of a 59-year-old female aluminum encephalopathy patient who had chronic renal failure and took 3.0 g hydroxy-aluminum gel per day for the control of serum phosphorus level during a 15-year period. Nine months before her death she developed disorientation, memory disturbance, emotional incontinence, general convulsions and consciousness disturbance. Neuropathologically, the brain showed nerve cell atrophy and mild loss with stromal spongiosis, proliferation of astrocytes and microglia in the cerebral cortex, basal ganglia and thalamus. Some nerve cells were stained immunohistochemically by phosphorylated neurofilament, but apparent neurofibrillary tangles were not observed. Aluminum was detected in the nerve cells of the cerebral cortex by X-ray microanalysis. Despite the long-term intake of aluminum, there were no neuropathological findings of Alzheimer's disease. The findings in our case suggested that aluminum alone might not develop Alzheimer's disease. [source]

    The neuropathology of frontotemporal lobar degeneration with respect to the cytological and biochemical characteristics of tau protein

    S. Taniguchi
    Pathological examinations, using a panel of tau and other antibodies, were performed on the brains from 55 consecutively acquired cases of frontotemporal lobar degeneration (FTLD). Clinically, these comprised 31 cases of frontotemporal dementia (FTD), 10 cases of motor neurone disease inclusion dementia (MNDID), seven cases of progressive aphasia (PA), four cases of semantic dementia (SD) and three cases of progressive apraxia (PAX). Tau pathology, in the form of neurofibrillary tangles (NFTs) and glial cell tangles, was present in six cases of FTD with parkinsonism linked to chromosome 17, five of these cases resulting from +16 splice-site mutation and one from +13 mutation in the tau gene. The insoluble tau proteins were comprised mostly of four-repeat (4-R) isoforms. Eight other cases of FTD, one of PA and all three cases of PAX showed tau-positive inclusions (Pick bodies) and swollen cells (Pick cells), characteristic of Pick's disease. In these cases, the insoluble tau proteins were present in most instances as three-repeat (3-R) tau isoforms, although two cases with a mixture of 3-R and 4-R isoforms were seen. One other case of FTD showed an unusual pathology characterized by massive extracellular deposition of tau protein, composed of 4-R tau isoforms, within white matter without neuronal or glial cell inclusions. However, 33 (60%) of 55 FTLD cases showed no tau pathology in the brain, except for the rare NFTs, composed of a mix of 3-R and 4-R isoforms, in some of the more elderly cases. Of these 33 cases, 13 had FTD, 10 had MNDID, six had PA and four had SD. The pathological changes present were those of a superficial cortical laminar microvacuolation with mild subpial and subcortical gliosis; the 10 MNDID cases had ubiquitin-positive inclusions in the cerebral cortex and hippocampus. These 33 nontau FTLD cases, along with five Alzheimer's disease (AD) and six Huntington's disease (HD) cases with severe pathology, showed a variable loss of soluble tau proteins, broadly comparable with the extent of neuronal loss from the cortex and loss of the intracortical perikaryal marker, NeuN, but unrelated to proteins within afferent projection fibres such as neurofilament and ,-synuclein. Levels of tau mRNA were decreased in parallel in the tau-negative FTLD cases and in the severe AD and HD cases. Hence, the loss of tau from these 33 nontau FTLD cases is just one aspect of a neurodegenerative process that destroys many components of the nerve cell machinery and does not represent a specific disordering of the cell's ability to form tau proteins or incorporate these into microtubules. [source]

    Developmental expression of glial cell-line derived neurotrophic factor, neurturin, and their receptor mRNA in the rat urinary bladder

    Takahiro Kawakami
    Abstract Aims: Glial cell-line derived neurotrophic factor (GDNF) and related factors neurturin (NRTN), artemin, and persephin are members of the GDNF family of neurotrophic factors. GDNF and NRTN bind to the tyrosine kinase receptor Ret and the receptors GFR,1 and GFR,2. The objective was to examine the developmental expression of GDNF, NRTN, and their receptors within the rat urinary bladder. Methods: Rat bladders dissected from embryonic day (E) 15, postnatal day (P) 0, P14, P28, and adult rats (P60) were investigated by semiquantitative reverse transcriptase polymerase chain reaction. Embryos (E15, E16, and E17) were immunohistochemically stained for neurofilament. Results: GDNF and Ret mRNA levels at E15 were the highest of all the stages we examined and then immediately decreased. In contrast, NRTN mRNA levels did not change between E15 and postnatal day 14; thereafter, they gradually but insignificantly increased. GFR,1 and GFR,2 mRNA levels were high at E15, after which their signal intensities decreased. In whole-mounted specimens, neurofilament-positive axons were first detected in the bladder at E16. Conclusions: Our results suggest that GDNF and NRTN may act as trophic factors for neural in-growth to the bladder and/or for the maintenance of mature neurons innervating the bladder. These factors might also be involved in bladder morphogenesis. Neurourol. Urodynam. 22:83,88, 2003. © 2003 Wiley-Liss, Inc. [source]

    Immunohistochemical analysis for histopathological subtypes in pediatric medulloblastomas

    Eun-Ik Son
    Medulloblastomas occurring in children represent a histological spectrum of varying anaplasia and nodularity. In order to determine whether immunohistochemical markers might be useful parameters in subclassifying these tumors, 17 pediatric medulloblastomas, including nine diffuse/non-anaplastic, four diffuse/anaplastic, three nodular/non-anaplastic and one nodular/anaplastic subtypes, were studied. In the present report, we investigate the expression of neural cell adhesion molecule (NCAM), nerve growth factor receptor (NGFR), neurofilament (NF), synaptophysin (SYN), glial fibrillary acidic protein (GFAP), S100, Bcl-2, and Ki-67 by using the immunohistochemistry against specific antibodies. This study showed that NGFR, NF, GFAP and S100 were not detected in anaplastic subtypes of medulloblastomas (0/5), while non-anaplastic subtypes were mainly expressed within the nodules. All 17 tumors were reactive for NCAM, SYN and Bcl-2. In addition, Ki-67 labeling indices for anaplastic subtypes (39.0 ± 7.42%) were significantly higher than that of non-anaplastic medulloblastomas (11.4 ± 8.04%; P < 0.0001). These results suggest that immunohistochemical markers are a useful adjunct in characterizing subtypes of pediatric medulloblastomas. [source]

    Immunohistochemical parcellation of the ferret (Mustela putorius) visual cortex reveals substantial homology with the cat (Felis catus)

    Jihane Homman-Ludiye
    Abstract Electrophysiological mapping of the adult ferret visual cortex has until now determined the existence of 12 retinotopically distinct areas; however, in the cat, another member of the Carnivora, 20 distinct visual areas have been identified by using retinotopic mapping and immunolabeling. In the present study, the immunohistochemical approach to demarcate the areal boundaries of the adult ferret visual cortex was applied in order to overcome the difficulties in accessing the sulcal surfaces of a small, gyrencephalic brain. Nonphosphorylated neurofilament (NNF) expression profiles were compared with another classical immunostain of cortical nuclei, Cat-301 chondroitin sulfate proteoglycan (CSPG). Together, these two markers reliably demarcated the borders of the 12 previously defined areas and revealed further arealization beyond those borders to a total of 19 areas: 21a and 21b; the anterolateral, posterolateral, dorsal, and ventral lateral suprasylvian areas (ALLS, PLLS, DLS, and VLS, respectively); and the splenial and cingulate visual areas (SVA and CVA). NNF expression profile and location of the newly defined areas correlate with previously defined areas in the cat. Moreover, NNF and Cat-301 together revealed discrete expression domains in the posteroparietal (PP) cortex, demarcating four subdivisions in the caudal lateral and medial domains (PPcL and PPcM) and rostral lateral and medial domains (PPrL and PPrM), where only two retinotopic maps have been previously identified (PPc and PPr). Taken together, these studies suggest that NNF and Cat-301 can illustrate the homology between cortical areas in different species and draw out the principles that have driven evolution of the visual cortex. J. Comp. Neurol. 518:4439,4462, 2010. © 2010 Wiley-Liss, Inc. [source]

    Cellular and molecular tunnels surrounding the forebrain commissures of human fetuses

    Roberto Lent
    Abstract Glial cells and extracellular matrix (ECM) molecules surround developing fiber tracts and are implicated in axonal pathfinding. These and other molecules are produced by these strategically located glial cells and have been shown to influence axonal growth across the midline in rodents. We searched for similar cellular and molecular structures surrounding the telencephalic commissures of fetal human brains. Paraffin-embedded brain sections were immunostained for glial fibrillary acidic protein (GFAP) and vimentin (VN) to identify glial cells; for microtubule-associated protein-2 (MAP-2) and neuronal nuclear protein (NeuN) to document neurons; for neurofilament (NF) to identify axons; and for chondroitin sulfate (CS), tenascin (TN), and fibronectin (FN) to show the ECM. As in rodents, three cellular clusters surrounding the corpus callosum were identified by their expression of GFAP and VN (but not MAP-2 or NeuN) from 13 to at least 18 weeks postovulation (wpo): the glial wedge, the glia of the indusium griseum, and the midline sling. CS and TN (but not FN) were expressed pericellularly in these cell groups. The anterior commissure was surrounded by a GFAP+/VN+ glial tunnel from 12 wpo, with TN expression seen between the GFAP+ cell bodies. The fimbria showed GFAP+/VN+ cells at its lateral and medial borders from 12 wpo, with pericellular expression of CS. The fornix showed GFAP+ cells somewhat later (16 wpo). Because these structures are similar to those described for rodents, we concluded that the axon guiding mechanisms postulated for commissural formation in nonhuman mammals may also be operant in the developing human brain. J. Comp. Neurol. 483:375,382, 2005. © 2005 Wiley-Liss, Inc. [source]

    Interstitial cells in the human prostate: A new therapeutic target?

    THE PROSTATE, Issue 4 2003
    Frank Van der Aa
    Abstract BACKGROUND Interstitial cells have been described in different human organs, including gut and bladder. In the gut they function as pacemaker cells, generating slow wave potentials. Absence or defects in these cells result in motility disorders. In the bladder these cells express the vanilloid receptor and may contribute to the working mechanism of vanilloid therapy. Recently, slow wave potentials and interstitial cells were described in the guinea-pig prostate. In this study we describe the presence of interstitial cells in the human prostate gland. METHODS We performed immunohistochemical staining for c-kit, vanilloid receptor (VR1), cannabinoid receptor (CB1) connexin43, and neurofilament on fresh frozen tissue from 14 prostatectomy specimens. RESULTS A large number of cells with a stellate aspect were noticed under the basal layer of the prostatic duct system and in between the smooth muscle cells. They were immunoreactive for c-kit, VR1, and connexin43 but not to CB1 or neurofilament. CONCLUSIONS There is evidence for interstitial cells in the human prostate. Taken together their topography and immunohistochemical characterization, the discovery of slow wave potentials in guinea pig prostate and the knowledge of interstitial cells in other organs, interstitial cells are likely to be involved in normal prostate physiology. Prostate 56: 250,255, 2003. © 2003 Wiley-Liss, Inc. [source]

    Defining Cytochemical Markers for Different Cell Types in the Equine Retina

    C. A. Deeg
    Summary The major cell types in the mammalian retina are photoreceptors, amacrine, horizontal, bipolar, ganglion and Mueller glial cells. Most of the specific cell types are conserved, but cytochemical markers vary between species. The aim of our study was to characterize cytochemically distinctive markers for different cell types in the equine retina. We were able to define specific markers for equine Mueller glial cells and photoreceptor cells. Furthermore, we describe markers for large ganglion cells, horizontal and amacrine cells and a subpopulation of bipolar cells. Additionally, discrimination between the inner plexiform layer and nerve fibre layer can be achieved by expression of syntaxin and neurofilament 200 respectively. [source]

    Axonal Pathology and Loss Precede Demyelination and Accompany Chronic Lesions in a Spontaneously Occurring Animal Model of Multiple Sclerosis

    BRAIN PATHOLOGY, Issue 3 2010
    Frauke Seehusen
    Abstract Axonal damage has been highlighted recently as a cause of neurological disability in various demyelinating diseases, including multiple sclerosis, either as a primary pathological change or secondary due to myelin loss. To characterize and quantify axonal damage and loss in canine distemper demyelinating leukoencephalomyelitis (DL), formalin-fixed paraffin-embedded cerebella were investigated histochemically and immunohistochemically using the modified Bielschowsky's silver stain as well as antibodies against nonphosphorylated (n-NF), phosphorylated neurofilament (p-NF) and ,-amyloid precursor protein (,-APP). Injured axons characterized by immunoreactivity against n-NF and ,-APP were detected in early distemper lesions without demyelination. In subacute and chronic demyelinating lesions the number of injured axons increased. Moreover, a significant decrease in axonal density was observed within lesions and in the normal appearing white matter in DL as determined by morphometric analyses using Bielschowsky's silver stain and p-NF immunohistochemistry. Summarized, the observed findings indicate that axonal damage (i) occurs early in DL; (ii) can be detected before myelin loss; and (iii) represents a pivotal feature in advanced lesions. It must be postulated that axonal damage plays an important role in the initial phase as a primary event and during progression of nervous distemper as a result of demyelination. [source]

    Unique Molecular Characteristics of Pediatric Myxopapillary Ependymoma

    BRAIN PATHOLOGY, Issue 3 2010
    Valerie N. Barton
    Abstract Myxopapillary ependymoma (MEPN) generally can be cured by gross total surgical resection and usually manifest a favorable prognosis. However, surgery is less curative in tumors that are large, multifocal or extend outside the thecal sac. Late recurrences may occur, particularly in pediatric patients. The role of adjuvant therapy is unclear in the clinical management of recurrent tumors. Clinical trial design requires a better understanding of tumor biology. Unique molecular features of MEPN were investigated by using microarray technology to compare the gene expression of five pediatric MEPN to 24 pediatric intracranial ependymoma (EPN). The upregulation of three genes of interest, homeobox B13 (HOXB13), neurofilament, light polypeptide (NEFL) and PDGFR,, was further studied by immunohistochemistry in a larger cohort that included adult MEPN and EPN specimens. Protein expression in MEPN was compared to subependymoma, spinal EPN, intracranial EPN and normal fetal and adult ependyma. Immunoreactivity for HOXB13, NEFL and PDGFR, was strongest in MEPN and virtually absent in subependymoma. Spinal and intracranial EPN generally expressed weak or focal staining. MEPN manifests unique gene and protein expression patterns compared to other EPNs. Aberrant expression of HOXB13 suggests possible recapitulation of developmental pathways in MEPN tumorigenesis. PDGFR, may be a potential therapeutic target in recurrent MEPN. [source]

    The presence of aberrant DNA methylation in noncancerous esophageal mucosae in association with smoking history

    CANCER, Issue 15 2009
    A target for risk diagnosis, prevention of esophageal cancers
    Abstract BACKGROUND: Esophageal squamous cell carcinomas (ESCCs) tend to have multiple primary lesions, and it is believed that they arise from background mucosae with accumulation of genetic/epigenetic alterations. In this study, the objective was to elucidate the effects of smoking and drinking on the accumulation of epigenetic alterations in background mucosae. METHODS: Genes that are silenced in human ESCCs were searched for by treating 3 ESCC cell lines with the demethylating agent, 5-aza-2,-deoxycytidine and performing oligonucleotide microarrays. Methylation levels were analyzed by quantitative methylation-specific polymerase chain reaction analysis of 60 ESCCs and their corresponding background mucosae. RESULTS: Forty-seven genes were identified as methylation-silenced in at least 1 of the 3 ESCC cell lines, and 14 of those genes (claudin 6 [CLDN6]; G protein-coupled receptor 158 [GPR158]; homeobox A9 [HOXA9]; metallothionein 1M [MT1M]; neurofilament, heavy polypeptide 200 kDa [NEFH]; plakophilin 1 [PKP1]; protein phosphatase 1, regulatory [inhibitor] subunit 14A [PPP1R14A]; pyrin domain and caspase recruitment domain containing [PYCARD]; R-spondin family, member 4 [RSPO4]; testis-specific protein, Y-encoded,like 5 [TSPYL5]; ubiquitin carboxyl-terminal esterase L1 [UCHL1]; zinc-finger protein 42 homolog [ZFP42]; zinc-finger protein interacting with K protein 1 homolog [ZIK1]; and zinc-finger and SCAN domain containing 18 [ZSCAN18]) were used as markers. In the background mucosae, methylation levels of 5 genes (HOXA9, MT1M, NEFH, RSPO4, and UCHL1) had significant correlations with smoking duration (, = .268; P = .044; , = .405; P = .002; , = .285; P = .032; , = .300; P = .024; and , = .437; P = .001, respectively). In contrast, an inverse correlation between PYCARD methylation levels and alcohol intake was observed (, = ,.334, P = .025) among individuals with the inactive aldehyde dehydrogenase 2 (ALDH2) genotype. CONCLUSIONS: The current results suggested that ESCCs developed from an epigenetic field for cancerization, which was induced by exposure to carcinogenic factors, such as tobacco smoking. The epigenetic field defect will be a novel target for risk diagnosis and prevention of ESCCs. Cancer 2009. © 2009 American Cancer Society. [source]

    Spider silk fibres in artificial nerve constructs promote peripheral nerve regeneration

    CELL PROLIFERATION, Issue 3 2008
    C. Allmeling
    Materials and methods: We compared isogenic nerve grafts to vein grafts with spider silk fibres, either alone or supplemented with Schwann cells, or Schwann cells and matrigel. Controls, consisting of veins and matrigel, were transplanted. After 6 months, regeneration was evaluated for clinical outcome, as well as for histological and morphometrical performance. Results: Nerve regeneration was achieved with isogenic nerve grafts as well as with all constructs, but not in the control group. Effective regeneration by isogenic nerve grafts and grafts containing spider silk was corroborated by diminished degeneration of the gastrocnemius muscle and by good histological evaluation results. Nerves stained for S-100 and neurofilament indicated existence of Schwann cells and axonal re-growth. Axons were aligned regularly and had a healthy appearance on ultrastructural examination. Interestingly, in contrast to recently published studies, we found that bridging an extensive gap by cell-free constructs based on vein and spider silk was highly effective in nerve regeneration. Conclusion: We conclude that spider silk is a viable guiding material for Schwann cell migration and proliferation as well as for axonal re-growth in a long-distance model for peripheral nerve regeneration. [source]

    Differential expression and localization of neuronal intermediate filament proteins within newly developing neurites in dissociated cultures of Xenopus laevis embryonic spinal cord

    CYTOSKELETON, Issue 1 2001
    Jayanthi Undamatla
    Abstract The molecular subunit composition of neurofilaments (NFs) progressively changes during axon development. In developing Xenopus laevis spinal cord, peripherin emerges at the earliest stages of neurite outgrowth. NF-M and XNIF (an ,-internexin-like protein) appear later, as axons continue to elongate, and NF-L is expressed after axons contact muscle. Because NFs are the most abundant component of the vertebrate axonal cytoskeleton, we must understand why these changes occur before we can fully comprehend how the cytoskeleton regulates axon growth and morphology. Knowing where these proteins are localized within developing neurites and how their expression changes with cell contact is essential for this understanding. Thus, we examined by immunofluorescence the expression and localization of these NF subunits within dissociated cultures of newly differentiating spinal cord neurons. In young neurites, peripherin was most abundant in distal neuritic segments, especially near branch points and extending into the central domain of the growth cone. In contrast, XNIF and NF-M were usually either absent from very young neurites or exhibited a proximal to distal gradient of decreasing intensity. In older neurites, XNIF and NF-M expression increased, whereas that of peripherin declined. All three of these proteins became more evenly distributed along the neurites, with some branches staining more intensely than others. At 24 h, NF-L appeared, and in 48-h cultures, its expression, along with that of NF-M, was greater in neurites contacting muscle cells, arguing that the upregulation of these two subunits is dependent on contact with target cells. Moreover, this contact had no effect on XNIF or peripherin expression. Our findings are consistent with a model in which peripherin plays an important structural role in growth cones, XNIF and NF-M help consolidate the intermediate filament cytoskeleton beginning in the proximal neurite, and increased levels of NF-L and NF-M help further solidify the cytoskeleton of axons that successfully reach their targets. Cell Motil. Cytoskeleton 49:16,32, 2001. © 2001 Wiley-Liss, Inc. [source]

    Cerebrospinal fluid and serum antibodies against neurofilaments in patients with amyotrophic lateral sclerosis

    L. Fialová
    Background:, The aim of the study was to assess autoimmune involvement in amyotrophic lateral sclerosis (ALS). Methods:, We measured IgG antibodies against light (NFL) and medium (NFM) subunits of neurofilaments using ELISA in paired cerebrospinal fluid (CSF) and serum samples from 38 ALS patients and 20 controls. Results:, Serum levels of anti-NFL were higher in ALS patients than in controls (P < 0.005). Serum anti-NFL antibodies and intrathecal anti-NFM antibodies were related to patient disability (serum anti-NFL: P < 0.05; intrathecal anti-NFM: P < 0.05). Anti-NFL levels were significantly correlated with anti-NFM levels in ALS (P < 0.001) and the control group (P < 0.0001) in the CSF, but not in serum. Anti-NFL and anti-NFM antibodies significantly correlated between serum and CSF in the ALS group (anti-NFL: P < 0.0001; anti-NFM: P < 0.001) and in the control group (anti-NFL: P < 0.05; anti-NFM: P < 0.05). Conclusions:, Autoimmune humoral response to neurocytoskeletal proteins is associated with ALS. [source]