WorldWideScience

Sample records for factor induced neural

  1. Diffusible Factors Secreted by Glioblastoma and Medulloblastoma Cells Induce Oxidative Stress in Bystander Neural Stem Progenitors.

    Science.gov (United States)

    Sharma, Neha; Colangelo, Nicholas W; de Toledo, Sonia M; Azzam, Edouard I

    2016-08-01

    Harmful effects that alter the homeostasis of neural stem or progenitor cells (NSPs) can affect regenerative processes in the central nervous system. We investigated the effect of soluble factors secreted by control or (137)Cs-γ-irradiated glioblastoma or medulloblastoma cells on redox-modulated endpoints in recipient human NSPs. Growth medium harvested from the nonirradiated brain tumor cells, following 24 h of growth, induced prominent oxidative stress in recipient NSPs as judged by overall increases in mitochondrial superoxide radical levels (p p21(Waf1) and p27(Kip1), and perturbations in cell cycle progression (p cells to radiation only slightly altered the induced oxidative changes in the bystander NSPs, except for medium from irradiated medulloblastoma cells that was more potent at inducing apoptosis in the NSPs than medium from nonirradiated cells (p cells is often used to support the growth of stem cells.

  2. Early expressions of hypoxia-inducible factor 1alpha and vascular endothelial growth factor increase the neuronal plasticity of activated endogenous neural stem cells after focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    Seung Song; Jong-Tae Park; Joo Young Na; Man-Seok Park; Jeong-Kil Lee; Min-Cheol Lee; Hyung-Seok Kim

    2014-01-01

    Endogenous neural stem cells become “activated” after neuronal injury, but the activation sequence and fate of endogenous neural stem cells in focal cerebral ischemia model are little known. We evaluated the relationships between neural stem cells and hypoxia-inducible fac-tor-1α and vascular endothelial growth factor expression in a photothromobotic rat stroke model using immunohistochemistry and western blot analysis. We also evaluated the chrono-logical changes of neural stem cells by 5-bromo-2′-deoxyuridine (BrdU) incorporation. Hypoxia-inducible factor-1α expression was initially increased from 1 hour after ischemic injury, followed by vascular endothelial growth factor expression. Hypoxia-inducible factor-1αimmunoreactivity was detected in the ipsilateral cortical neurons of the infarct core and peri-in-farct area. Vascular endothelial growth factor immunoreactivity was detected in bilateral cortex, but ipsilateral cortex staining intensity and numbers were greater than the contralateral cortex. Vascular endothelial growth factor immunoreactive cells were easily found along the peri-infarct area 12 hours after focal cerebral ischemia. The expression of nestin increased throughout the microvasculature in the ischemic core and the peri-infarct area in all experimental rats after 24 hours of ischemic injury. Nestin immunoreactivity increased in the subventricular zone during 12 hours to 3 days, and prominently increased in the ipsilateral cortex between 3-7 days. Nes-tin-labeled cells showed dual differentiation with microvessels near the infarct core and reactive astrocytes in the peri-infarct area. BrdU-labeled cells were increased gradually from day 1 in the ipsilateral subventricular zone and cortex, and numerous BrdU-labeled cells were observed in the peri-infarct area and non-lesioned cortex at 3 days. BrdU-labeled cells rather than neu-rons, were mainly co-labeled with nestin and GFAP. Early expressions of hypoxia-inducible factor-1α and

  3. Regulation of hypoxia-inducible factor-α isoforms and redox state by carotid body neural activity in rats.

    Science.gov (United States)

    Peng, Ying-Jie; Yuan, Guoxiang; Khan, Shakil; Nanduri, Jayasri; Makarenko, Vladislav V; Reddy, Vaddi Damodara; Vasavda, Chirag; Kumar, Ganesh K; Semenza, Gregg L; Prabhakar, Nanduri R

    2014-09-01

    Previous studies reported that chronic intermittent hypoxia (CIH) results in an imbalanced expression of hypoxia-inducible factor-α (HIF-α) isoforms and oxidative stress in rodents, which may be due either to the direct effect of CIH or indirectly via hitherto uncharacterized mechanism(s). As neural activity is a potent regulator of gene transcription, we hypothesized that carotid body (CB) neural activity contributes to CIH-induced HIF-α isoform expression and oxidative stress in the chemoreflex pathway. Experiments were performed on adult rats exposed to CIH for 10 days. Rats exposed to CIH exhibited: increased HIF-1α and decreased HIF-2α expression; increased NADPH oxidase 2 and decreased superoxide dismutase 2 expression; and oxidative stress in the nucleus tractus solitarius and rostral ventrolateral medulla as well as in the adrenal medulla (AM), a major end organ of the sympathetic nervous system. Selective ablation of the CB abolished these effects. In the AM, sympathetic activation by the CB chemoreflex mediates CIH-induced HIF-α isoform imbalance via muscarinic acetylcholine receptor-mediated Ca(2+) influx, and the resultant activation of mammalian target of rapamycin pathway and calpain proteases. Rats exposed to CIH presented with hypertension, elevated sympathetic activity and increased circulating catecholamines. Selective ablation of either the CB (afferent pathway) or sympathetic innervation to the AM (efferent pathway) abolished these effects. These observations uncover CB neural activity-dependent regulation of HIF-α isoforms and the redox state by CIH in the central and peripheral nervous systems associated with the chemoreflex.

  4. Neurite outgrowth induced by a synthetic peptide ligand of neural cell adhesion molecule requires fibroblast growth factor receptor activation

    DEFF Research Database (Denmark)

    Rønn, L C; Doherty, P; Holm, A;

    2000-01-01

    The neural cell adhesion molecule NCAM is involved in axonal outgrowth and target recognition in the developing nervous system. In vitro, NCAM-NCAM binding has been shown to induce neurite outgrowth, presumably through an activation of fibroblast growth factor receptors (FGFRs). We have recently...... identified a neuritogenic ligand, termed the C3 peptide, of the first immunoglobulin (lg) module of NCAM using a combinatorial library of synthetic peptides. Here we investigate whether stimulation of neurite outgrowth by this synthetic ligand of NCAM involves FGFRs. In primary cultures of cerebellar neurons...... from wild-type mice, the C3 peptide stimulated neurite outgrowth. This response was virtually absent in cultures of cerebellar neurons from transgenic mice expressing a dominant-negative form of the FGFR1. Likewise, in PC12E2 cells transiently expressing a dominant-negative form of the mouse FGFR1...

  5. Neural induction and factors that stabilize a neural fate

    OpenAIRE

    Rogers, Crystal; Moody, Sally A.; Casey, Elena

    2009-01-01

    The neural ectoderm of vertebrates forms when the BMP signaling pathway is suppressed. Herein we review the molecules that directly antagonize extracellular BMP and the signaling pathways that further contribute to reduce BMP activity in the neural ectoderm. Downstream of neural induction, a large number of “neural fate stabilizing” (NFS) transcription factors are expressed in the presumptive neural ectoderm, developing neural tube, and ultimately in neural stem cells. Herein we review what i...

  6. Connective-Tissue Growth Factor (CTGF/CCN2 Induces Astrogenesis and Fibronectin Expression of Embryonic Neural Cells In Vitro.

    Directory of Open Access Journals (Sweden)

    Fabio A Mendes

    Full Text Available Connective-tissue growth factor (CTGF is a modular secreted protein implicated in multiple cellular events such as chondrogenesis, skeletogenesis, angiogenesis and wound healing. CTGF contains four different structural modules. This modular organization is characteristic of members of the CCN family. The acronym was derived from the first three members discovered, cysteine-rich 61 (CYR61, CTGF and nephroblastoma overexpressed (NOV. CTGF is implicated as a mediator of important cell processes such as adhesion, migration, proliferation and differentiation. Extensive data have shown that CTGF interacts particularly with the TGFβ, WNT and MAPK signaling pathways. The capacity of CTGF to interact with different growth factors lends it an important role during early and late development, especially in the anterior region of the embryo. ctgf knockout mice have several cranio-facial defects, and the skeletal system is also greatly affected due to an impairment of the vascular-system development during chondrogenesis. This study, for the first time, indicated that CTGF is a potent inductor of gliogenesis during development. Our results showed that in vitro addition of recombinant CTGF protein to an embryonic mouse neural precursor cell culture increased the number of GFAP- and GFAP/Nestin-positive cells. Surprisingly, CTGF also increased the number of Sox2-positive cells. Moreover, this induction seemed not to involve cell proliferation. In addition, exogenous CTGF activated p44/42 but not p38 or JNK MAPK signaling, and increased the expression and deposition of the fibronectin extracellular matrix protein. Finally, CTGF was also able to induce GFAP as well as Nestin expression in a human malignant glioma stem cell line, suggesting a possible role in the differentiation process of gliomas. These results implicate ctgf as a key gene for astrogenesis during development, and suggest that its mechanism may involve activation of p44/42 MAPK signaling

  7. Oleanolic Acid Induces Differentiation of Neural Stem Cells to Neurons: An Involvement of Transcription Factor Nkx-2.5

    Directory of Open Access Journals (Sweden)

    You Ning

    2015-01-01

    Full Text Available Neural stem cells (NSCs harbor the potential to differentiate into neurons, astrocytes, and oligodendrocytes under normal conditions and/or in response to tissue damage. NSCs open a new way of treatment of the injured central nervous system and neurodegenerative disorders. Thus far, few drugs have been developed for controlling NSC functions. Here, the effect as well as mechanism of oleanolic acid (OA, a pentacyclic triterpenoid, on NSC function was investigated. We found OA significantly inhibited neurosphere formation in a dose-dependent manner and achieved a maximum effect at 10 nM. OA also reduced 5-ethynyl-2′-deoxyuridine (EdU incorporation into NSCs, which was indicative of inhibited NSC proliferation. Western blotting analysis revealed the protein levels of neuron-specific marker tubulin-βIII (TuJ1 and Mash1 were increased whilst the astrocyte-specific marker glial fibrillary acidic protein (GFAP decreased. Immunofluorescence analysis showed OA significantly elevated the percentage of TuJ1-positive cells and reduced GFAP-positive cells. Using DNA microarray analysis, 183 genes were differentially regulated by OA. Through transcription factor binding site analyses of the upstream regulatory sequences of these genes, 87 genes were predicted to share a common motif for Nkx-2.5 binding. Finally, small interfering RNA (siRNA methodology was used to silence Nkx-2.5 expression and found silence of Nkx-2.5 alone did not change the expression of TuJ-1 and the percentage of TuJ-1-positive cells. But in combination of OA treatment and silence of Nkx-2.5, most effects of OA on NSCs were abolished. These results indicated that OA is an effective inducer for NSCs differentiation into neurons at least partially by Nkx-2.5-dependent mechanism.

  8. Neural cell adhesion molecule-180-mediated homophilic binding induces epidermal growth factor receptor (EGFR) down-regulation and uncouples the inhibitory function of EGFR in neurite outgrowth

    DEFF Research Database (Denmark)

    Povlsen, Gro Klitgaard; Berezin, Vladimir; Bock, Elisabeth

    2008-01-01

    The neural cell adhesion molecule (NCAM) plays important roles in neuronal development, regeneration, and synaptic plasticity. NCAM homophilic binding mediates cell adhesion and induces intracellular signals, in which the fibroblast growth factor receptor plays a prominent role. Recent studies...... not require NCAM-mediated fibroblast growth factor receptor activation....... on axon guidance in Drosophila suggest that NCAM also regulates the epidermal growth factor receptor (EGFR) (Molecular and Cellular Neuroscience, 28, 2005, 141). A possible interaction between NCAM and EGFR in mammalian cells has not been investigated. The present study demonstrates for the first time...

  9. Brain-Derived Neurotrophic Factor Loaded PS80 PBCA Nanocarrier for In Vitro Neural Differentiation of Mouse Induced Pluripotent Stem Cells

    Science.gov (United States)

    Chung, Chiu-Yen; Lin, Martin Hsiu-Chu; Lee, I-Neng; Lee, Tsong-Hai; Lee, Ming-Hsueh; Yang, Jen-Tsung

    2017-01-01

    Brain derived neurotrophic factor (BDNF) can induce neural differentiation in stem cells and has the potential for repair of the nervous system. In this study, a polysorbate 80-coated polybutylcyanoacrylate nanocarrier (PS80 PBCA NC) was constructed to deliver plasmid DNAs (pDNAs) containing BDNF gene attached to a hypoxia-responsive element (HRE-cmvBDNF). The hypoxia-sensing mechanism of BDNF expression and inductiveness of the nano-formulation on mouse induced pluripotent stem cells (iPSCs) to differentiate into neurons following hypoxia was tested in vitro with immunofluorescent staining and Western blotting. The HRE-cmvBDNF appeared to adsorb onto the surface of PS80 PBCA NC, with a resultant mean diameter of 92.6 ± 1.0 nm and zeta potential of −14.1 ± 1.1 mV. HIF-1α level in iPSCs was significantly higher in hypoxia, which resulted in a 51% greater BDNF expression when transfected with PS80 PBCA NC/HRE-cmvBDNF than those without hypoxia. TrkB and phospho-Akt were also elevated which correlated with neural differentiation. The findings suggest that PS80 PBCA NC too can be endocytosed to serve as an efficient vector for genes coupled to the HRE in hypoxia-sensitive cells, and activation of the PI3/Akt pathway in iPSCs by BDNF is capable of neural lineage specification. PMID:28335495

  10. Dopaminergic neuronal differentiation from the forebrain-derived human neural stem cells induced in cultures by using a combination of BMP-7 and pramipexole with growth factors

    Directory of Open Access Journals (Sweden)

    Hongna eYang

    2016-04-01

    Full Text Available Transplantation of dopaminergic (DA neurons is considered to be the most promising therapeutic strategy for replacing degenerated dopamine cells in the midbrain of Parkinson’s disease (PD, thereby restoring normal neural circuit function and slow clinical progression of the disease. Human neural stem cells (hNSCs derived from fetal forebrain are thought to be the important cell sources for producing DA neurons because of their multipotency for differentiation and long-term expansion property in cultures. However, low DA differentiation of the forebrain-derived hNSCs limited their therapeutic potential in PD. In the current study, we explored a combined application of Pramipexole (PRX, bone morphogenetic proteins 7 (BMP-7, and growth factors, including acidic fibroblast factor (aFGF, forskolin, and phorbol-12-myristae-13-acetate (TPA, to induce differentiation of forebrain-derived hNSCs towards DA neurons in cultures. We found that DA neuron-associated genes, including Nurr1, Neurogenin2 (Ngn2, and tyrosine hydroxylase (TH were significantly increased after 24h of differentiation by RT-PCR analysis (p<0.01. Fluorescent examination showed that about 25% of cells became TH-positive neurons at 24h, about 5% of cells became VMAT2 (vascular monoamine transporter 2-positive neurons, and less than 5% of cells became DAT (dopamine transporter-positive neurons at 72h following differentiation in cultures. Importantly, these TH-, VMAT2- and DAT-expressing neurons were able to release dopamine into cultures under both of the basal and evoked conditions. Dopamine levels released by DA neurons produced using our protocol were significantly higher compared to the control groups (P<0.01, as examined by ELISA. Our results demonstrated that the combination of PRX, BMP-7, and growth factors was able to greatly promote differentiation of the forebrain-derived hNSCs into DA-releasing neurons.

  11. Matriptase is required for the active form of hepatocyte growth factor induced Met, focal adhesion kinase and protein kinase B activation on neural stem/progenitor cell motility.

    Science.gov (United States)

    Fang, Jung-Da; Lee, Sheau-Ling

    2014-07-01

    Hepatocyte growth factor (HGF) is a chemoattractant and inducer for neural stem/progenitor (NS/P) cell migration. Although the type II transmembrane serine protease, matriptase (MTP) is an activator of the latent HGF, MTP is indispensable on NS/P cell motility induced by the active form of HGF. This suggests that MTP's action on NS/P cell motility involves mechanisms other than proteolytic activation of HGF. In the present study, we investigate the role of MTP in HGF-stimulated signaling events. Using specific inhibitors of phosphatidylinositol-3-kinase (PI3K), protein kinase B (Akt) or focal adhesion kinase (FAK), we demonstrated that in NS/P cells HGF-activated c-Met induces PI3k-Akt signaling which then leads to FAK activation. This signaling pathway ultimately induces MMP2 expression and NS/P cell motility. Knocking down of MTP in NS/P cells with specific siRNA impaired HGF-stimulation of c-Met, Akt and FAK activation, blocked HGF-induced production of MMP2 and inhibited HGF-stimulated NS/P cell motility. MTP-knockdown NS/P cells cultured in the presence of recombinant protein of MTP protease domain or transfected with the full-length wild-type but not the protease-defected MTP restored HGF-responsive events in NS/P cells. In addition to functioning as HGF activator, our data revealed novel function of MTP on HGF-stimulated c-Met signaling activation.

  12. Neuron-specific enolase expression in a rat model of radiation-induced brain injury following vascular endothelial growth factor-modified neural stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    Songhua Xiao; Chaohui Duan; Qingyu Shen; Yigang Xing; Ying Peng; Enxiang Tao; Jun Liu

    2009-01-01

    BACKGROUND:Previous studies have shown that transplantation of vascular endothelial growth factor (VEGF)-modified neural stem cells (NSC) provides better outcomes,compared with neural stem cells,in the treatment of brain damage.OBJECTIVE:To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury,and to determine neuron-specific enolase (NSE) expression in the brain.DESIGN,TIME,AND SETTING:The randomized,controlled study was performed at the Linbaixin Experimental Center,Second Affiliated Hospital,Sun Yat-sen University,China from November 2007 to October 2008.MATERIALS:VEGF-medified C17.2 NSCs were supplied by Harvard Medical School,USA.Streptavidin-biotin-peroxidase-complex kit (Boster,China) and 5,6-carboxyfluorescein diacetate succinimidyl ester (Fluka,USA) were used in this study.METHODS:A total of 84 Sprague Dawley rats were randomly assigned to a blank control group (n=20),model group (n=20),NSC group (n=20),and a VEGF-modified NSC group (n=24).Rat models of radiation-induced brain injury were established in the model,NSC,and VEGF-modified NSC groups.At 1 week following model induction,10 μL (5×10~4 cells/μL) VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups.A total of 10 μL saline was injected into rats from the blank control and model groups.MAIN OUTCOME MEASURES:NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation.RESULTS:NSE expression was significantly decreased in the brains of radiation-induced brain injury rats (P<0.05).The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups,compared with the model group (P<0.05).NSE expression significantly increased in the VEGF-modified NSC group,compared with the NSC group,at 6 weeks following transplantation (P<0.05).CONCLUSION:VEGF-modified NSC

  13. Seizure induces activation of multiple subtypes of neural progenitors and growth factors in hippocampus with neuronal maturation confined to dentate gyrus

    Energy Technology Data Exchange (ETDEWEB)

    Indulekha, Chandrasekharan L.; Sanalkumar, Rajendran [Neuro Stem Cell Biology Laboratory, Department of Neurobiology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, Kerala 695 014 (India); Thekkuveettil, Anoopkumar [Molecular Medicine, Biomedical Technology Wing, Sree Chitra Thirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala (India); James, Jackson, E-mail: jjames@rgcb.res.in [Neuro Stem Cell Biology Laboratory, Department of Neurobiology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, Kerala 695 014 (India)

    2010-03-19

    Adult hippocampal neurogenesis is altered in response to different physiological and pathological stimuli. GFAP{sup +ve}/nestin{sup +ve} radial glial like Type-1 progenitors are considered to be the resident stem cell population in adult hippocampus. During neurogenesis these Type-1 progenitors matures to GFAP{sup -ve}/nestin{sup +ve} Type-2 progenitors and then to Type-3 neuroblasts and finally differentiates into granule cell neurons. In our study, using pilocarpine-induced seizure model, we showed that seizure initiated activation of multiple progenitors in the entire hippocampal area such as DG, CA1 and CA3. Seizure induction resulted in activation of two subtypes of Type-1 progenitors, Type-1a (GFAP{sup +ve}/nestin{sup +ve}/BrdU{sup +ve}) and Type-1b (GFAP{sup +ve}/nestin{sup +ve}/BrdU{sup -ve}). We showed that majority of Type-1b progenitors were undergoing only a transition from a state of dormancy to activated form immediately after seizures rather than proliferating, whereas Type-1a showed maximum proliferation by 3 days post-seizure induction. Type-2 (GFAP{sup -ve}/nestin{sup +ve}/BrdU{sup +ve}) progenitors were few compared to Type-1. Type-3 (DCX{sup +ve}) progenitors showed increased expression of immature neurons only in DG region by 3 days after seizure induction indicating maturation of progenitors happens only in microenvironment of DG even though progenitors are activated in CA1 and CA3 regions of hippocampus. Also parallel increase in growth factors expression after seizure induction suggests that microenvironmental niche has a profound effect on stimulation of adult neural progenitors.

  14. Growth factor deprivation induces an alternative non-apoptotic death mechanism that is inhibited by Bcl2 in cells derived from neural precursor cells.

    Science.gov (United States)

    Cárdenas-Aguayo, María del Carmen; Santa-Olalla, Jesús; Baizabal, José-Manuel; Salgado, Luis-Miguel; Covarrubias, Luis

    2003-12-01

    Although apoptosis has been considered the typical mechanism for physiological cell death, presently alternative mechanisms need to be considered. We previously showed that fibroblast growth factor-2 (FGF2) could act as a survival factor for neural precursor cells. To study the death mechanism activated by the absence of this growth factor, we followed the changes in cell morphology and determined cell viability by staining with several dyes after FGF2 removal from mesencephalic neural-progenitor-cell cultures. The changes observed did not correspond to those associated with apoptosis. After 48 h in the absence of FGF2, cells began to develop vacuoles in their cytoplasm, a phenotype that became very obvious 3-5 days later. Double-membrane vacuoles containing cell debris were observed. Vacuolated cells did not stain with either ethidium bromide or trypan Blue, and did not show chromatin condensations. Nonetheless, during the course of culture, vacuolated cells formed aggregates with highly condensed chromatin and detached from the plate. Neural progenitor cells grown in the presence of FGF2 did not display any of those characteristics. The vacuolated phenotype could be reversed by the addition of FGF2. Typical autophagy inhibitors such as 3-MA and LY294002 inhibited vacuole development, whereas a broad-spectrum caspase inhibitor did not. Interestingly, Bcl-2 overexpression retarded vacuole development. In conclusion, we identified a death autophagy-like mechanism activated by the lack of a specific survival factor that can be inhibited by Bcl2. We propose that anti-apoptotic Bcl2 family members are key molecules controlling death activation independently of the cell degeneration mechanism used.

  15. Bitter taste stimuli induce differential neural codes in mouse brain.

    Directory of Open Access Journals (Sweden)

    David M Wilson

    Full Text Available A growing literature suggests taste stimuli commonly classified as "bitter" induce heterogeneous neural and perceptual responses. Here, the central processing of bitter stimuli was studied in mice with genetically controlled bitter taste profiles. Using these mice removed genetic heterogeneity as a factor influencing gustatory neural codes for bitter stimuli. Electrophysiological activity (spikes was recorded from single neurons in the nucleus tractus solitarius during oral delivery of taste solutions (26 total, including concentration series of the bitter tastants quinine, denatonium benzoate, cycloheximide, and sucrose octaacetate (SOA, presented to the whole mouth for 5 s. Seventy-nine neurons were sampled; in many cases multiple cells (2 to 5 were recorded from a mouse. Results showed bitter stimuli induced variable gustatory activity. For example, although some neurons responded robustly to quinine and cycloheximide, others displayed concentration-dependent activity (p<0.05 to quinine but not cycloheximide. Differential activity to bitter stimuli was observed across multiple neurons recorded from one animal in several mice. Across all cells, quinine and denatonium induced correlated spatial responses that differed (p<0.05 from those to cycloheximide and SOA. Modeling spatiotemporal neural ensemble activity revealed responses to quinine/denatonium and cycloheximide/SOA diverged during only an early, at least 1 s wide period of the taste response. Our findings highlight how temporal features of sensory processing contribute differences among bitter taste codes and build on data suggesting heterogeneity among "bitter" stimuli, data that challenge a strict monoguesia model for the bitter quality.

  16. Glial cell line-derived neurotrophic factor (GDNF) induces neuritogenesis in the cochlear spiral ganglion via neural cell adhesion molecule (NCAM).

    Science.gov (United States)

    Euteneuer, Sara; Yang, Kuo H; Chavez, Eduardo; Leichtle, Anke; Loers, Gabriele; Olshansky, Adel; Pak, Kwang; Schachner, Melitta; Ryan, Allen F

    2013-05-01

    Glial cell line-derived neurotrophic factor (GDNF) increases survival and neurite extension of spiral ganglion neurons (SGNs), the primary neurons of the auditory system, via yet unknown signaling mechanisms. In other cell types, signaling is achieved by the GPI-linked GDNF family receptor α1 (GFRα1) via recruitment of transmembrane receptors: Ret (re-arranged during transformation) and/or NCAM (neural cell adhesion molecule). Here we show that GDNF enhances neuritogenesis in organotypic cultures of spiral ganglia from 5-day-old rats and mice. Addition of GFRα1-Fc increases this effect. GDNF/GFRα1-Fc stimulation activates intracellular PI3K/Akt and MEK/Erk signaling cascades as detected by Western blot analysis of cultures prepared from rats at postnatal days 5 (P5, before the onset of hearing) and 20 (P20, after the onset of hearing). Both cascades mediate GDNF stimulation of neuritogenesis, since application of the Akt inhibitor Wortmannin or the Erk inhibitor U0126 abolished GDNF/GFRα1-Fc stimulated neuritogenesis in P5 rats. Since cultures of P5 NCAM-deficient mice failed to respond by neuritogenesis to GDNF/GFRα1-Fc, we conclude that NCAM serves as a receptor for GDNF signaling responsible for neuritogenesis in early postnatal spiral ganglion.

  17. Embryonic neural inducing factor churchill is not a DNA-binding zinc finger protein: solution structure reveals a solvent-exposed beta-sheet and zinc binuclear cluster.

    Science.gov (United States)

    Lee, Brian M; Buck-Koehntop, Bethany A; Martinez-Yamout, Maria A; Dyson, H Jane; Wright, Peter E

    2007-08-31

    Churchill is a zinc-containing protein that is involved in neural induction during embryogenesis. At the time of its discovery, it was thought on the basis of sequence alignment to contain two zinc fingers of the C4 type. Further, binding of an N-terminal GST-Churchill fusion protein to a particular DNA sequence was demonstrated by immunoprecipitation selection assay, suggesting that Churchill may function as a transcriptional regulator by sequence-specific DNA binding. We show by NMR solution structure determination that, far from containing canonical C4 zinc fingers, the protein contains three bound zinc ions in novel coordination sites, including an unusual binuclear zinc cluster. The secondary structure of Churchill is also unusual, consisting of a highly solvent-exposed single-layer beta-sheet. Hydrogen-deuterium exchange and backbone relaxation measurements reveal that Churchill is unusually dynamic on a number of time scales, with the exception of regions surrounding the zinc coordinating sites, which serve to stabilize the otherwise unstructured N terminus and the single-layer beta-sheet. No binding of Churchill to the previously identified DNA sequence could be detected, and extensive searches using DNA sequence selection techniques could find no other DNA sequence that was bound by Churchill. Since the N-terminal amino acids of Churchill form part of the zinc-binding motif, the addition of a fusion protein at the N terminus causes loss of zinc and unfolding of Churchill. This observation most likely explains the published DNA-binding results, which would arise due to non-specific interaction of the unfolded protein in the immunoprecipitation selection assay. Since Churchill does not appear to bind DNA, we suggest that it may function in embryogenesis as a protein-interaction factor.

  18. Hepatocyte growth factor activator inhibitor-1 is induced by bone morphogenetic proteins and regulates proliferation and cell fate of neural progenitor cells.

    Directory of Open Access Journals (Sweden)

    Raili Koivuniemi

    Full Text Available BACKGROUND: Neural progenitor cells (NPCs in the developing neuroepithelium are regulated by intrinsic and extrinsic factors. There is evidence that NPCs form a self-supporting niche for cell maintenance and proliferation. However, molecular interactions and cell-cell contacts and the microenvironment within the neuroepithelium are largely unknown. We hypothesized that cellular proteases especially those associated with the cell surface of NPCs play a role in regulation of progenitor cells in the brain. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we show that NPCs, isolated from striatal anlage of developing rat brain, express hepatocyte growth factor activator inhibitor-1 and -2 (HAI-1 and HAI-2 that are cell surface-linked serine protease inhibitors. In addition, radial glia cells derived from mouse embryonic stem cells also express HAI-1 and HAI-2. To study the functional significance of HAI-1 and HAI-2 in progenitor cells, we modulated their levels using expression plasmids or silencing RNA (siRNA transfected into the NPCs. Data showed that overexpression of HAI-1 or HAI-2 decreased cell proliferation of cultured NPCs, whilst their siRNAs had opposite effects. HAI-1 also influenced NPC differentiation by increasing the number of glial fibrillary acidic protein (GFAP expressing cells in the culture. Expression of HAI-1 in vivo decreased cell proliferation in developing neuroepithelium in E15 old animals and promoted astrocyte cell differentiation in neonatal animals. Studying the regulation of HAI-1, we observed that Bone morphogenetic protein-2 (BMP-2 and BMP-4 increased HAI-1 levels in the NPCs. Experiments using HAI-1-siRNA showed that these BMPs act on the NPCs partly in a HAI-1-dependent manner. CONCLUSIONS: This study shows that the cell-surface serine protease inhibitors, HAI-1 and HAI-2 influence proliferation and cell fate of NPCs and their expression levels are linked to BMP signaling. Modulation of the levels and actions of HAI-1

  19. Signaling of glial cell line-derived neurotrophic factor and its receptor GFRα1 induce Nurr1 and Pitx3 to promote survival of grafted midbrain-derived neural stem cells in a rat model of Parkinson disease.

    Science.gov (United States)

    Lei, Zhinian; Jiang, Yu; Li, Tao; Zhu, Jianbao; Zeng, Shuilin

    2011-09-01

    Glial cell line-derived neurotrophic factor (GDNF) and its receptor GFRα1 have been implicated in the survival of ventral midbrain dopaminergic (DA) neurons, but the molecular mechanisms bywhich GDNF generates DA neurons in grafted midbrain-derived neural stem cells (mNSCs) are not understood. Midbrain-derived neural stem cells isolated from rat embryonic mesencephalon (embryonic day 12) were treated with GDNF or in combination with GFRα1 small interfering RNA. Reverse transcription-polymerase chain reaction, Western blot, and immunocytochemistry were used totest the expression of the orphan nuclear receptor Nurr1 and thetranscription factor Pitx3 and newborn tyrosine hydroxylase (TH)-positive cells. Treatment of mNSCs with GDNF increased mNSCs' sphere diameter, reduced expression of caspase 3, and increased expression of Bcl-2. Glial cell line-derived neurotrophic factor-treated mNSCs enhanced Nurr1 and Pitx3 expression and the fraction of TH-, TH/Pitx3-, and TH/Nurr1-positive cells in culture. Grafted GDNF-treated mNSCs significantly decreased apomorphine-induced rotation behavior in 6-hydroxydopamine-lesioned rats. Glialcell line-derived neurotrophic factor-treated mNSCs showed increased numbers of TH/Pitx3- and TH/Nurr1-postivie cells. The effect elicited by GDNF was inhibited by small interfering RNA-mediated knockdown of GFRα1. Our data demonstrate the contribution of GDNF to DA neuron development and may also elucidate pathogenetic mechanisms in Parkinson disease and contribute to the development of novel therapies for the disorder.

  20. File list: Unc.Neu.10.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Neu.10.AllAg.Induced_neural_progenitors mm9 Unclassified Neural Induced neural ...progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Neu.10.AllAg.Induced_neural_progenitors.bed ...

  1. File list: Pol.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Neu.05.AllAg.Induced_neural_progenitors mm9 RNA polymerase Neural Induced neura...l progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  2. File list: Oth.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Neu.50.AllAg.Induced_neural_progenitors mm9 TFs and others Neural Induced neura...l progenitors SRX323564,SRX323573 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  3. File list: DNS.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Neu.05.AllAg.Induced_neural_progenitors mm9 DNase-seq Neural Induced neural pro...genitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  4. File list: Unc.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Neu.05.AllAg.Induced_neural_progenitors mm9 Unclassified Neural Induced neural ...progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  5. File list: His.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Neu.20.AllAg.Induced_neural_progenitors mm9 Histone Neural Induced neural proge...nitors SRX667381,SRX668240 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  6. File list: His.Neu.10.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Neu.10.AllAg.Induced_neural_progenitors mm9 Histone Neural Induced neural proge...nitors SRX667381,SRX668240 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Neu.10.AllAg.Induced_neural_progenitors.bed ...

  7. File list: His.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Neu.50.AllAg.Induced_neural_progenitors mm9 Histone Neural Induced neural proge...nitors SRX667381,SRX668240 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  8. File list: Pol.Neu.10.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Neu.10.AllAg.Induced_neural_progenitors mm9 RNA polymerase Neural Induced neural... progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Neu.10.AllAg.Induced_neural_progenitors.bed ...

  9. File list: Pol.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Neu.20.AllAg.Induced_neural_progenitors mm9 RNA polymerase Neural Induced neural... progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  10. File list: His.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Neu.05.AllAg.Induced_neural_progenitors mm9 Histone Neural Induced neural proge...nitors SRX667381,SRX668240 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  11. File list: Pol.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Neu.50.AllAg.Induced_neural_progenitors mm9 RNA polymerase Neural Induced neural... progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  12. File list: Unc.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Neu.20.AllAg.Induced_neural_progenitors mm9 Unclassified Neural Induced neural ...progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  13. File list: Unc.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Neu.50.AllAg.Induced_neural_progenitors mm9 Unclassified Neural Induced neural ...progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  14. File list: DNS.Neu.10.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Neu.10.AllAg.Induced_neural_progenitors mm9 DNase-seq Neural Induced neural pro...genitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Neu.10.AllAg.Induced_neural_progenitors.bed ...

  15. File list: Oth.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Neu.05.AllAg.Induced_neural_progenitors mm9 TFs and others Neural Induced neural... progenitors SRX323573,SRX323564 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  16. File list: DNS.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Neu.50.AllAg.Induced_neural_progenitors mm9 DNase-seq Neural Induced neural pro...genitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  17. File list: DNS.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Neu.20.AllAg.Induced_neural_progenitors mm9 DNase-seq Neural Induced neural pro...genitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  18. File list: Oth.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Neu.20.AllAg.Induced_neural_progenitors mm9 TFs and others Neural Induced neura...l progenitors SRX323564,SRX323573 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  19. Study on neural network model for calculating subsidence factor

    Institute of Scientific and Technical Information of China (English)

    GUO Wen-bing; ZHANG Jie

    2007-01-01

    The major factors influencing subsidence factor were comprehensively analyzed. Then the artificial neural network model for calculating subsidence factor was set up with the theory of artificial neural network (ANN). A large amount of data from observation stations in China was collected and used as learning and training samples to train and test the artificial neural network model. The calculated results of the ANN model and the observed values were compared and analyzed in this paper. The results demonstrate that many factors can be considered in this model and the result is more precise and closer to observed values to calculate the subsidence factor by the ANN model. It can satisfy the need of engineering.

  20. Human leukemia inhibitory factor produced by the ExpressTec method from rice (Oryza sativa L.) is active in human neural stem cells and mouse induced pluripotent stem cells

    Science.gov (United States)

    Alfano, Randall; Youngblood, Bradford A; Zhang, Deshui; Huang, Ning; MacDonald, Clinton C

    2014-01-01

    Stem cell-based therapy has the potential to treat an array of human diseases. However, to study the therapeutic potential and safety of these cells, a scalable cell culture medium is needed that is free of human or bovine-derived serum proteins. Thus, cost-effective recombinant serum proteins and cytokines are needed to produce such mediums. One such cytokine, leukemia inhibitory factor (LIF), has been shown to be a critical paracrine factor that maintains stem cell pluripotency in murine embryonic stem cells and human naïve stem cells while simultaneously inhibiting differentiation. We recently produced recombinant human LIF (rhLIF) in a rice-based protein expression system known as ExpressTec.12 We described expression of rice-derived rhLIF and demonstrated its biological equivalency to E. coli-derived rhLIF in traditional and embryonic mouse stem cell systems. Here we describe the expression yield of rice-derived rhLIF and the scale up production capacity. We provide further evidence of the efficacy of rice-derived rhLIF in additional stem cell systems including human neural stem cells and mouse induced pluripotent stem (iPS) cells. The expression level, biological activity, and potential for production at commercial scale of rice-derived rhLIF provides a proof-of-principal for ExpressTec-derived proteins to produce regulatory-friendly, high performance, and dependable stem cell media. PMID:24776984

  1. Influence of endogenous ciliary neurotrophic factor on neural differentiation of adult rat hippocampal progenitors

    Institute of Scientific and Technical Information of China (English)

    Jun Ding; Zhili He; Juan Ruan; Ying Liu; Chengxin Gong; Shenggang Sun; Honghui Chen

    2013-01-01

    Ciliary neurotrophic factor is the only known neurotrophic factor that can promote differentiation of hippocampal neural progenitor cells to glial cells and neurons in adult rats. This process is similar to spontaneous differentiation. Therefore, ciliary neurotrophic factor may be involved in spontaneous differentiation of neural stem cells. To verify this hypothesis, the present study isolated neural progenitor cells from adult male rats and cultured them in vitro. Results showed that when neural progenitor cells were cultured in the absence of mitogen fibroblast growth factor-2 or epidermal growth factor, they underwent spontaneous differentiation into neurons and glial cells. Western blot and immunocytochemical staining showed that exogenous ciliary neurotrophic factor strongly induced adult hippocampal progenitor cells to differentiate into neurons and glial cells. Moreover, passage 4 adult hippocampal progenitor cells expressed high levels of endogenous ciliary neurotrophic factor, and a neutralizing antibody against ciliary neurotrophic factor prevented the spontaneous neuronal and glial differentiation of adult hippocampal progenitor cells. These results suggest that the spontaneous differentiation of adult hippocampal progenitor cells is mediated partially by endogenous ciliary neurotrophic factor.

  2. A Right Coprime Factorization of Neural State Space Models

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon

    2007-01-01

    In recent years, various methods for identification of nonlinear systems in closed loop using open-loop approaches have received considerable attention. However, these methods rely on differentially coprime factorizations of the nonlinear plants, which can be difficult to compute in practice....... To address this issue, this paper presents various technical results leading up to explicit formulae for right coprime factorizations of neural state space models, i.e., nonlinear system models represented in state space using neural networks, which satisfy a Bezout identity. ...

  3. Therapeutic Potential of Induced Neural Stem Cells for Parkinson's Disease.

    Science.gov (United States)

    Choi, Dong-Hee; Kim, Ji-Hye; Kim, Sung Min; Kang, Kyuree; Han, Dong Wook; Lee, Jongmin

    2017-01-22

    Parkinson's disease (PD) is a chronic, neurodegenerative disorder that results from the loss of cells in the substantia nigra (SN) which is located in the midbrain. However, no cure is available for PD. Recently, fibroblasts have been directly converted into induced neural stem cells (iNSCs) via the forced expression of specific transcription factors. Therapeutic potential of iNSC in PD has not been investigated yet. Here, we show that iNSCs directly converted from mouse fibroblasts enhanced functional recovery in an animal model of PD. The rotational behavior test was performed to assess recovery. Our results indicate that iNSC transplantation into the striatum of 6-hydroxydopamine (6-OHDA)-injected mice can significantly reduce apomorphine-induced rotational asymmetry. The engrafted iNSCs were able to survive in the striatum and migrated around the medial forebrain bundle and the SN pars compacta. Moreover, iNSCs differentiated into all neuronal lineages. In particular, the transplanted iNSCs that committed to the glial lineage were significantly increased in the striatum of 6-OHDA-injected mice. Engrafted iNSCs differentiated to dopaminergic (DA) neurons and migrated into the SN in the 6-OHDA lesion mice. Therefore, iNSC transplantation serves as a valuable tool to enhance the functional recovery in PD.

  4. A Neural Network Model of Retrieval-Induced Forgetting

    Science.gov (United States)

    Norman, Kenneth A.; Newman, Ehren L.; Detre, Greg

    2007-01-01

    Retrieval-induced forgetting (RIF) refers to the finding that retrieving a memory can impair subsequent recall of related memories. Here, the authors present a new model of how the brain gives rise to RIF in both semantic and episodic memory. The core of the model is a recently developed neural network learning algorithm that leverages regular…

  5. Pig Induced Pluripotent Stem Cell-Derived Neural Rosettes Parallel Human Differentiation Into Sensory Neural Subtypes.

    Science.gov (United States)

    Webb, Robin L; Gallegos-Cárdenas, Amalia; Miller, Colette N; Solomotis, Nicholas J; Liu, Hong-Xiang; West, Franklin D; Stice, Steven L

    2017-04-01

    The pig is the large animal model of choice for study of nerve regeneration and wound repair. Availability of porcine sensory neural cells would conceptually allow for analogous cell-based peripheral nerve regeneration in porcine injuries of similar severity and size to those found in humans. After recently reporting that porcine (or pig) induced pluripotent stem cells (piPSCs) differentiate into neural rosette (NR) structures similar to human NRs, here we demonstrate that pig NR cells could differentiate into neural crest cells and other peripheral nervous system-relevant cell types. Treatment with either bone morphogenetic protein 4 or fetal bovine serum led to differentiation into BRN3A-positive sensory cells and increased expression of sensory neuron TRK receptor gene family: TRKA, TRKB, and TRKC. Porcine sensory neural cells would allow determination of parallels between human and porcine cells in response to noxious stimuli, analgesics, and reparative mechanisms. In vitro differentiation of pig sensory neurons provides a novel model system for neural cell subtype specification and would provide a novel platform for the study of regenerative therapeutics by elucidating the requirements for innervation following injury and axonal survival.

  6. Noise Induced Coherence in Neural Networks

    CERN Document Server

    Rappel, W J; Rappel, Wouter-Jan; Karma, Alain

    1996-01-01

    We investigate numerically the dynamics of large networks of $N$ globally pulse-coupled integrate and fire neurons in a noise-induced synchronized state. The powerspectrum of an individual element within the network is shown to exhibit in the thermodynamic limit ($N\\rightarrow \\infty$) a broadband peak and an additional delta-function peak that is absent from the powerspectrum of an isolated element. The powerspectrum of the mean output signal only exhibits the delta-function peak. These results are explained analytically in an exactly soluble oscillator model with global phase coupling.

  7. Pulsed DC Electric Field-Induced Differentiation of Cortical Neural Precursor Cells.

    Directory of Open Access Journals (Sweden)

    Hui-Fang Chang

    Full Text Available We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz. The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders.

  8. Pulsed DC Electric Field–Induced Differentiation of Cortical Neural Precursor Cells

    Science.gov (United States)

    Chang, Hui-Fang; Lee, Ying-Shan; Tang, Tang K.; Cheng, Ji-Yen

    2016-01-01

    We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC) pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs) could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz). The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders. PMID:27352251

  9. [Induced-division of neurons derived from neural stem cells].

    Science.gov (United States)

    Lin, Qiu-Xia; Que, Hai-Ping; Lu, Shuang-Hong; Liu, Shao-Jun

    2004-04-25

    In order to explore if mature neurons derived from neural stem cells have the potentiality to divide, we utilized the chemical digestion method to disperse the adult rat brain tissue into single cells, and culture them in serum-free medium. After being cultured for about eight days in vitro, the neural stem cells were induced to differentiate into neurons. The neurons were further induced to divide. Utilizing the method of serial photograph and NF-160 immunocytochemistry, the processes of division of some neurons were recorded. At the same time, PCNA+NF-160 (or Chat, GABA, GAD) double label were used to investigate if the dividing-neurons were mature ones. After the neural stem cells were induced to differentiate in vitro for eight days, they possessed the shape and character of mature neurons. The differentiated neuron had a big nucleus and one or two distinct nucleolus in the nuclear. Within the perikaryon,there were a large amount of dense and Nissl body-like structure. Several long processes emerged from various locations of the cell body. Then, EGF and bFGF were added into the medium to induce division. After two days of induced-division, neuron-like cells were observed to divide; moreover, the number of neuron-like cells in the region increased continually. Immunocytochemistry demonstrated these cells were NF-160-positive. Serial photographs of dividing-process of neuron-like cells were obtained and their daughter cells were also NF-160-positive. After PCNA+NF-160 (or Chat, GABA, GAD) double label, some cells showed brown cell plasma and black nucleus. The above-mentioned results indicate that neurons, which were previously thought to be end-differentiated, can be re-called into cell cycle under appropriate conditions. Mature neurons still have the potential to divide, proliferate and self-renew.

  10. Plasmid-based generation of induced neural stem cells from adult human fibroblasts

    Directory of Open Access Journals (Sweden)

    Philipp Capetian

    2016-10-01

    Full Text Available Direct reprogramming from somatic to neural cell types has become an alternative to induced pluripotent stem cells. Most protocols employ viral expression systems, posing the risk of random genomic integration. Recent developments led to plasmid-based protocols, lowering this risk. However, these protocols either relied on continuous presence of a variety of small molecules or were only able to reprogram murine cells. We therefore established a reprogramming protocol based on vectors containing the Epstein-Barr virus (EBV-derived oriP/EBNA1 as well as the defined expression factors Oct3/4, Sox2, Klf4, L-myc, Lin28, and a small hairpin directed against p53. We employed a defined neural medium in combination with the neurotrophins bFGF, EGF and FGF4 for cultivation without the addition of small molecules. After reprogramming, cells demonstrated a temporary increase in the expression of endogenous Oct3/4. We obtained induced neural stem cells (iNSC 30 days after transfection. In contrast to previous results, plasmid vectors as well as a residual expression of reprogramming factors remained detectable in all cell lines. Cells showed a robust differentiation into neuronal (72% and glial cells (9% astrocytes, 6% oligodendrocytes. Despite the temporary increase of pluripotency-associated Oct3/4 expression during reprogramming, we did not detect pluripotent stem cells or non-neural cells in culture (except occasional residual fibroblasts. Neurons showed electrical activity and functional glutamatergic synapses. Our results demonstrate that reprogramming adult human fibroblasts to iNSC by plasmid vectors and basic neural medium without small molecules is possible and feasible. However, a full set of pluripotency-associated transcription factors may indeed result in the acquisition of a transient (at least partial pluripotent intermediate during reprogramming. In contrast to previous reports, the EBV-based plasmid system remained present and active inside

  11. File list: InP.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Neu.20.AllAg.Induced_neural_progenitors mm9 Input control Neural Induced neural... progenitors SRX323563,SRX323574,SRX667380,SRX668238 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  12. File list: NoD.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Neu.50.AllAg.Induced_neural_progenitors mm9 No description Neural Induced neura...l progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  13. File list: InP.Neu.50.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Neu.50.AllAg.Induced_neural_progenitors mm9 Input control Neural Induced neural... progenitors SRX323563,SRX323574,SRX667380,SRX668238 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Neu.50.AllAg.Induced_neural_progenitors.bed ...

  14. File list: NoD.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Neu.05.AllAg.Induced_neural_progenitors mm9 No description Neural Induced neural... progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  15. File list: InP.Neu.05.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Neu.05.AllAg.Induced_neural_progenitors mm9 Input control Neural Induced neural... progenitors SRX667380,SRX668238,SRX323563,SRX323574 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Neu.05.AllAg.Induced_neural_progenitors.bed ...

  16. File list: NoD.Neu.10.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Neu.10.AllAg.Induced_neural_progenitors mm9 No description Neural Induced neural... progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Neu.10.AllAg.Induced_neural_progenitors.bed ...

  17. File list: NoD.Neu.20.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Neu.20.AllAg.Induced_neural_progenitors mm9 No description Neural Induced neural... progenitors http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Neu.20.AllAg.Induced_neural_progenitors.bed ...

  18. File list: InP.Neu.10.AllAg.Induced_neural_progenitors [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Neu.10.AllAg.Induced_neural_progenitors mm9 Input control Neural Induced neural... progenitors SRX668238,SRX667380,SRX323563,SRX323574 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Neu.10.AllAg.Induced_neural_progenitors.bed ...

  19. Adolescent nicotine induces persisting changes in development of neural connectivity.

    Science.gov (United States)

    Smith, Robert F; McDonald, Craig G; Bergstrom, Hadley C; Ehlinger, Daniel G; Brielmaier, Jennifer M

    2015-08-01

    Adolescent nicotine induces persisting changes in development of neural connectivity. A large number of brain changes occur during adolescence as the CNS matures. These changes suggest that the adolescent brain may still be susceptible to developmental alterations by substances which impact its growth. Here we review recent studies on adolescent nicotine which show that the adolescent brain is differentially sensitive to nicotine-induced alterations in dendritic elaboration, in several brain areas associated with processing reinforcement and emotion, specifically including nucleus accumbens, medial prefrontal cortex, basolateral amygdala, bed nucleus of the stria terminalis, and dentate gyrus. Both sensitivity to nicotine, and specific areas responding to nicotine, differ between adolescent and adult rats, and dendritic changes in response to adolescent nicotine persist into adulthood. Areas sensitive to, and not sensitive to, structural remodeling induced by adolescent nicotine suggest that the remodeling generally corresponds to the extended amygdala. Evidence suggests that dendritic remodeling is accompanied by persisting changes in synaptic connectivity. Modeling, electrophysiological, neurochemical, and behavioral data are consistent with the implication of our anatomical studies showing that adolescent nicotine induces persisting changes in neural connectivity. Emerging data thus suggest that early adolescence is a period when nicotine consumption, presumably mediated by nicotine-elicited changes in patterns of synaptic activity, can sculpt late brain development, with consequent effects on synaptic interconnection patterns and behavior regulation. Adolescent nicotine may induce a more addiction-prone phenotype, and the structures altered by nicotine also subserve some emotional and cognitive functions, which may also be altered. We suggest that dendritic elaboration and associated changes are mediated by activity-dependent synaptogenesis, acting in part

  20. Inducing dopaminergic differentiation of expanded rat mesencephalic neural stem cells by ascorbic acid in vitro

    Institute of Scientific and Technical Information of China (English)

    ZHENG Min; WANG Dongmei; HOU Lingling; LI Haimin; XIE Chao; JIAO Wencang; BAI Cixian; WANG Yaping; PEI Xuetao

    2004-01-01

    Ascorbic acid (AA) induced differentiation of neural stem cells (NSCs) into dopaminergic (DAergic) neurons is reported.NSCs derived from rat mesencephalon were maintained and expanded in a defined medium containing mitogens of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF).Compared with the control, ascorbic acid treatment led to more DAergic neuronal differentiation as indicated by the expression of tyrosine hydroxylase (TH) and dopamine transporter (DAT), which are specific markers of dopamine neurons.AA induction also enhanced expression of Nurr1 and Shh.PD98059, an inhibitor of mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway, could block AA-induced Nurr1, TH and DAT mRNA expression.The results might suggest a new strategy to provide enough dopaminergic cells for the therapy of Parkinson's disease (PD), and Nurr1 and ERK signaling pathway might participate in the AA-induced DAergic differentiation.

  1. Selective migration of neuralized embryonic stem cells to stem cell factor and media conditioned by glioma cell lines

    Science.gov (United States)

    Serfozo, Peter; Schlarman, Maggie S; Pierret, Chris; Maria, Bernard L; Kirk, Mark D

    2006-01-01

    Background Pluripotent mouse embryonic stem (ES) cells can be induced in vitro to become neural progenitors. Upon transplantation, neural progenitors migrate toward areas of damage and inflammation in the CNS. We tested whether undifferentiated and neuralized mouse ES cells migrate toward media conditioned by glioma cell lines (C6, U87 & N1321) or Stem Cell Factor (SCF). Results Cell migration assays revealed selective migration by neuralized ES cells to conditioned media as well as to synthetic SCF. Migration of undifferentiated ES cells was extensive, but not significantly different from that of controls (Unconditioned Medium). RT-PCR analysis revealed that all the three tumor cell lines tested synthesized SCF and that both undifferentiated and neuralized ES cells expressed c-kit, the receptor for SCF. Conclusion Our results demonstrate that undifferentiated ES cells are highly mobile and that neural progenitors derived from ES cells are selectively attracted toward factors produced by gliomas. Given that the glioma cell lines synthesize SCF, SCF may be one of several factors that contribute to the selective migration observed. PMID:16436212

  2. Selective migration of neuralized embryonic stem cells to stem cell factor and media conditioned by glioma cell lines

    Directory of Open Access Journals (Sweden)

    Maria Bernard L

    2006-01-01

    Full Text Available Abstract Background Pluripotent mouse embryonic stem (ES cells can be induced in vitro to become neural progenitors. Upon transplantation, neural progenitors migrate toward areas of damage and inflammation in the CNS. We tested whether undifferentiated and neuralized mouse ES cells migrate toward media conditioned by glioma cell lines (C6, U87 & N1321 or Stem Cell Factor (SCF. Results Cell migration assays revealed selective migration by neuralized ES cells to conditioned media as well as to synthetic SCF. Migration of undifferentiated ES cells was extensive, but not significantly different from that of controls (Unconditioned Medium. RT-PCR analysis revealed that all the three tumor cell lines tested synthesized SCF and that both undifferentiated and neuralized ES cells expressed c-kit, the receptor for SCF. Conclusion Our results demonstrate that undifferentiated ES cells are highly mobile and that neural progenitors derived from ES cells are selectively attracted toward factors produced by gliomas. Given that the glioma cell lines synthesize SCF, SCF may be one of several factors that contribute to the selective migration observed.

  3. Folic acid supplementation during pregnancy protects against lipopolysaccharide-induced neural tube defects in mice.

    Science.gov (United States)

    Zhao, Mei; Chen, Yuan-Hua; Chen, Xue; Dong, Xu-Ting; Zhou, Jun; Wang, Hua; Wu, Shu-Xian; Zhang, Cheng; Xu, De-Xiang

    2014-01-13

    Folic acid is a water-soluble B-complex vitamin. Increasing evidence demonstrates that physiological supply of folic acid during pregnancy prevents folic acid deficiency-related neural tube defects (NTDs). Previous studies showed that maternal lipopolysaccharide (LPS) exposure caused NTDs in rodents. The aim of this study was to investigate the effects of high-dose folic acid supplementation during pregnancy on LPS-induced NTDs. Pregnant mice were intraperitoneally injected with LPS (20 μg/kg/d) from gestational day (GD) 8 to GD12. As expected, a five-day LPS injection resulted in 19.96% of fetuses with NTDs. Interestingly, supplementation with folic acid (3mg/kg/d) during pregnancy significantly alleviated LPS-induced NTDs. Additionally, folic acid significantly attenuated LPS-induced fetal growth restriction and skeletal malformations. Additional experiment showed that folic acid attenuated LPS-induced glutathione (GSH) depletion in maternal liver and placentas. Moreover, folic acid significantly attenuated LPS-induced expression of placental MyD88. Additionally, folic acid inhibited LPS-induced c-Jun NH2-terminal kinase (JNK) phosphorylation and nuclear factor kappa B (NF-κB) activation in placentas. Correspondingly, folic acid significantly attenuated LPS-induced tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in placentas, maternal serum and amniotic fluid. In conclusion, supplementation with high-dose folic acid during pregnancy protects against LPS-induced NTDs through its anti-inflammatory and anti-oxidative effects.

  4. Contribution of visual and circadian neural circuits to memory for prolonged mating induced by rivals.

    Science.gov (United States)

    Kim, Woo Jae; Jan, Lily Yeh; Jan, Yuh Nung

    2012-06-01

    Rival exposure causes Drosophila melanogaster males to prolong mating. Longer mating duration (LMD) may enhance reproductive success, but its underlying mechanism is currently unknown. We found that LMD is context dependent and can be induced solely via visual stimuli. In addition, we found that LMD involves neural circuits that are important for visual memory, including central neurons in the ellipsoid body, but not the mushroom bodies or the fan-shaped bodies, and may rely on the rival exposure memory lasting for several hours. LMD is affected by a subset of learning and memory mutants. LMD depends on the circadian clock genes timeless and period, but not Clock or cycle, and persists in many arrhythmic conditions. Moreover, LMD critically depends on a subset of pigment dispersing factor neurons rather than the entire circadian neural circuit. Our study thus delineates parts of the molecular and cellular basis for LMD, a plastic social behavior elicited by visual cues.

  5. Angiogenic factors stimulate growth of adult neural stem cells.

    Directory of Open Access Journals (Sweden)

    Andreas Androutsellis-Theotokis

    Full Text Available BACKGROUND: The ability to grow a uniform cell type from the adult central nervous system (CNS is valuable for developing cell therapies and new strategies for drug discovery. The adult mammalian brain is a source of neural stem cells (NSC found in both neurogenic and non-neurogenic zones but difficulties in culturing these hinders their use as research tools. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that NSCs can be efficiently grown in adherent cell cultures when angiogenic signals are included in the medium. These signals include both anti-angiogenic factors (the soluble form of the Notch receptor ligand, Dll4 and pro-angiogenic factors (the Tie-2 receptor ligand, Angiopoietin 2. These treatments support the self renewal state of cultured NSCs and expression of the transcription factor Hes3, which also identifies the cancer stem cell population in human tumors. In an organotypic slice model, angiogenic factors maintain vascular structure and increase the density of dopamine neuron processes. CONCLUSIONS/SIGNIFICANCE: We demonstrate new properties of adult NSCs and a method to generate efficient adult NSC cultures from various central nervous system areas. These findings will help establish cellular models relevant to cancer and regeneration.

  6. Ceramide is involved in alcohol-induced neural proliferation****

    Institute of Scientific and Technical Information of China (English)

    Zhixin Wang; Tongxing Deng; Jiexin Deng; Jinbo Deng; Xiaoqun Gao; Yuanyuan Shi; Bin Liu; Zhanyou Ma; Haixiao Jin

    2013-01-01

    Prenatal alcohol exposure, especial y during early pregnancy, can lead to fetal alcohol syndrome. The pharmacological and toxicological mechanisms of ethanol are related to the effects of ceramide. In this study, we established an alcohol exposure model in wild-type mice and in knockout mice for the key enzyme involved in ceramide metabolism, sphingomyelin synthase 2. This model received daily intragastric administration of 25%ethanol, and pups were used at postnatal days 0, 7, 14, 30 for experiments. Serology and immunofluorescence staining found that ethanol exposure dose-dependently reduced blood sphingomyelin levels in two genotypes of pups, and increased neural cel proliferation and the number of new neurons in the hippocampal dentate gyrus. Western blot analysis showed that the relative expression level of protein kinase C α increased in two notypes of pups after ethanol exposure. Compared with wild-type pups, the expression level of the important activator protein of the ceramide/ceramide-1-phosphate pathway, protein kinase Cα, was reduced in the hippocampus of sphingomyelin synthase 2 knockouts. Our findings il ustrate that ceramide is involved in alcohol-induced neural proliferation in the hippocampal dentate gyrus of pups after prenatal ethanol exposure, and the mechanism may be associated with increased pression of protein kinase Cαactivating the ceramide/ceramide-1-phosphate pathway.

  7. Neural cell adhesion molecule induces intracellular signaling via multiple mechanisms of Ca2+ homeostasis

    DEFF Research Database (Denmark)

    Kiryushko, Darya; Korshunova, Irina; Berezin, Vladimir;

    2006-01-01

    The neural cell adhesion molecule (NCAM) plays a pivotal role in the development of the nervous system, promoting neuronal differentiation via homophilic (NCAM-NCAM) as well as heterophilic (NCAM-fibroblast growth factor receptor [FGFR]) interactions. NCAM-induced intracellular signaling has been....... The first pathway was associated with activation of FGFR, phospholipase Cgamma, and production of diacylglycerol, and the second pathway involved Src-family kinases. Moreover, NCAM-mediated Ca2+ entry required activation of nonselective cation and T-type voltage-gated Ca2+ channels. These channels, together...

  8. Neuroprotective effects of ginsenoside Rg1-induced neural stem cell transplantation on hypoxic-ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    Ying-bo Li

    2015-01-01

    Full Text Available Ginsenoside Rg1 is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether neural stem cell transplantation after induction has therapeutic effects on hypoxic-ischemic encephalopathy, we cultured neural stem cells in 10-80 µM ginsenoside Rg1. Immunohistochemistry revealed that of the concentrations tested, 20 mM ginsenoside Rg1 had the greatest differentiation-inducing effect and was the concentration used for subsequent experiments. Whole-cell patch clamp showed that neural stem cells induced by 20 µM ginsenoside Rg1 were more mature than non-induced cells. We then established neonatal rat models of hypoxic-ischemic encephalopathy using the suture method, and ginsenoside Rg1-induced neural stem cells were transplanted via intracerebroventricular injection. These tests confirmed that neural stem cells induced by ginsenoside had fewer pathological lesions and had a significantly better behavioral capacity than model rats that received saline. Transplanted neural stem cells expressed neuron-specific enolase, and were mainly distributed in the hippocampus and cerebral cortex. The present data suggest that ginsenoside Rg1-induced neural stem cells can promote the partial recovery of complicated brain functions in models of hypoxic-ischemic encephalopathy.

  9. Neuroprotective effects of ginsenoside Rg1-induced neural stem cell transplantation on hypoxic-ischemic encephalopathy

    Institute of Scientific and Technical Information of China (English)

    Ying-bo Li; Yan Wang; Ji-ping Tang; Di Chen; Sha-li Wang

    2015-01-01

    Ginsenoside Rg1 is the major pharmacologically active component of ginseng, and is reported to have various therapeutic actions. To determine whether it induces the differentiation of neural stem cells, and whether neural stem cell transplantation after induction has therapeutic effects on hypoxic-ischemic encephalopathy, we cultured neural stem cells in 10–80 μM ginsenoside Rg1. Immunohistochemistry revealed that of the concentrations tested, 20 mM ginsenoside Rg1 had the greatest differentiation-inducing effect and was the concentration used for subsequent exper-iments. Whole-cell patch clamp showed that neural stem cells induced by 20 μM ginsenoside Rg1 were more mature than non-induced cells. We then established neonatal rat models of hypox-ic-ischemic encephalopathy using the suture method, and ginsenoside Rg1-induced neural stem cells were transplantedvia intracerebroventricular injection. These tests conifrmed that neural stem cells induced by ginsenoside had fewer pathological lesions and had a signiifcantly better behavioral capacity than model rats that received saline. Transplanted neural stem cells expressed neuron-speciifc enolase, and were mainly distributed in the hippocampus and cerebral cortex. The present data suggest that ginsenoside Rg1-induced neural stem cells can promote the partial recovery of complicated brain functions in models of hypoxic-ischemic encephalopathy.

  10. The effects of erdosteine, N-acetylcysteine, and vitamin E on nicotine-induced apoptosis of hippocampal neural cells.

    Science.gov (United States)

    Demiralay, Rezan; Gürsan, Nesrin; Erdem, Havva

    2008-08-01

    This study investigated the frequency of apoptosis in rat hippocampal neural cells after intraperitoneal nicotine injection, examining the roles of the inflammatory markers myeloperoxidase (MPO) and tumor necrosis factor alpha (TNF-alpha) in nicotine-induced brain damage and the protective effects of three known antioxidant agents, N-acetylcysteine (NAC), erdosteine, and vitamin E. Female Wistar rats were divided into seven groups, each composed of nine rats: 2 negative control groups, 2 positive control groups, one erdosteine-treated group (500 mg/kg), one NAC-treated group (500 mg/kg), and one vitamin E-treated group (500 mg/kg). Nicotine was intraperitoneally injected at a dosage of 0.6 mg/kg for 21 days. Following nicotine injection, the antioxidants were administered orally; treatment was continued until the rats were killed. Apoptosis level in hippocampal neural cells was determined by using TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick endlabeling) method. Staining of cytoplasmic TNF-alpha in hippocampal neural cells and hippocampus MPO activity were evaluated by immunohistochemistry. Nicotine administration had no effect on local TNF-alpha production, or hippocampal MPO activity. The treatments with erdosteine, NAC and vitamin E significantly reduced the rate of nicotine-induced hippocampal neural cell apoptosis. This findings suggest that erdosteine and NAC can be as effective as vitamin E in protecting against nicotine-induced hippocampal neural cell apoptosis.

  11. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews.

    Science.gov (United States)

    Xiong, Liu-Lin; Chen, Zhi-Wei; Wang, Ting-Hua

    2016-04-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  12. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    Institute of Scientific and Technical Information of China (English)

    Liu-lin Xiong; Zhi-wei Chen; Ting-hua Wang

    2016-01-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promotein vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, lfuorescence mi-croscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These ifndings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  13. Neural correlates of induced motion perception in the human brain.

    Science.gov (United States)

    Takemura, Hiromasa; Ashida, Hiroshi; Amano, Kaoru; Kitaoka, Akiyoshi; Murakami, Ikuya

    2012-10-10

    A physically stationary stimulus surrounded by a moving stimulus appears to move in the opposite direction. There are similarities between the characteristics of this phenomenon of induced motion and surround suppression of directionally selective neurons in the brain. Here, functional magnetic resonance imaging was used to investigate the link between the subjective perception of induced motion and cortical activity. The visual stimuli consisted of a central drifting sinusoid surrounded by a moving random-dot pattern. The change in cortical activity in response to changes in speed and direction of the central stimulus was measured. The human cortical area hMT+ showed the greatest activation when the central stimulus moved at a fast speed in the direction opposite to that of the surround. More importantly, the activity in this area was the lowest when the central stimulus moved in the same direction as the surround and at a speed such that the central stimulus appeared to be stationary. The results indicate that the activity in hMT+ is related to perceived speed modulated by induced motion rather than to physical speed or a kinetic boundary. Early visual areas (V1, V2, V3, and V3A) showed a similar pattern; however, the relationship to perceived speed was not as clear as that in hMT+. These results suggest that hMT+ may be a neural correlate of induced motion perception and play an important role in contrasting motion signals in relation to their surrounding context and adaptively modulating our motion perception depending on the spatial context.

  14. Generation of Neural Crest-Like Cells From Human Periodontal Ligament Cell-Derived Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Tomokiyo, Atsushi; Hynes, Kim; Ng, Jia; Menicanin, Danijela; Camp, Esther; Arthur, Agnes; Gronthos, Stan; Mark Bartold, Peter

    2017-02-01

    Neural crest cells (NCC) hold great promise for tissue engineering, however the inability to easily obtain large numbers of NCC is a major factor limiting their use in studies of regenerative medicine. Induced pluripotent stem cells (iPSC) are emerging as a novel candidate that could provide an unlimited source of NCC. In the present study, we examined the potential of neural crest tissue-derived periodontal ligament (PDL) iPSC to differentiate into neural crest-like cells (NCLC) relative to iPSC generated from a non-neural crest derived tissue, foreskin fibroblasts (FF). We detected high HNK1 expression during the differentiation of PDL and FF iPSC into NCLC as a marker for enriching for a population of cells with NCC characteristics. We isolated PDL iPSC- and FF iPSC-derived NCLC, which highly expressed HNK1. A high proportion of the HNK1-positive cell populations generated, expressed the MSC markers, whilst very few cells expressed the pluripotency markers or the hematopoietic markers. The PDL and FF HNK1-positive populations gave rise to smooth muscle, neural, glial, osteoblastic and adipocytic like cells and exhibited higher expression of smooth muscle, neural, and glial cell-associated markers than the PDL and FF HNK1-negative populations. Interestingly, the HNK1-positive cells derived from the PDL-iPSC exhibited a greater ability to differentiate into smooth muscle, neural, glial cells and adipocytes, than the HNK1-positive cells derived from the FF-iPSC. Our work suggests that HNK1-enriched NCLC from neural crest tissue-derived iPSC more closely resemble the phenotypic and functional hallmarks of NCC compared to the HNK1-low population and non-neural crest iPSC-derived NCLC. J. Cell. Physiol. 232: 402-416, 2017. © 2016 Wiley Periodicals, Inc.

  15. The Evaluation of Nerve Growth Factor Over Expression on Neural Lineage Specific Genes in Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Mortazavi Yousef

    2016-07-01

    Full Text Available Objective Treatment and repair of neurodegenerative diseases such as brain tumors, spinal cord injuries, and functional disorders, including Alzheimer’s disease, are challenging problems. A common treatment approach for such disorders involves the use of mesenchymal stem cells (MSCs as an alternative cell source to replace injured cells. However, use of these cells in hosts may potentially cause adverse outcomes such as tumorigenesis and uncontrolled differentiation. In attempt to generate mesenchymal derived neural cells, we have infected MSCs with recombinant lentiviruses that expressed nerve growth factor (NGF and assessed their neural lineage genes. Materials and Methods In this experimental study, we cloned the NGF gene sequence into a helper dependent lentiviral vector that contained the green fluorescent protein (GFP gene. The recombinant vector was amplified in DH5 bacterial cells. Recombinant viruses were generated in the human embryonic kidney 293 (HEK-293 packaging cell line with the helper vectors and analyzed under fluorescent microscopy. Bone marrow mesenchymal cells were infected by recombinant viruses for three days followed by assessment of neural differentiation. We evaluated expression of NGF through measurement of the NGF protein in culture medium by ELISA; neural specific genes were quantified by real-time polymerase chain reaction (PCR. Results We observed neural morphological changes after three days. Quantitative PCR showed that expressions of NESTIN, glial derived neurotrophic factor (GDNF, glial fibrillary acidic protein (GFAP and Microtubule-associated protein 2 (MAP2 genes increased following induction of NGF overexpression, whereas expressions of endogenous NGF and brain derived neural growth factor (BDNF genes reduced. Conclusion Ectopic expression of NGF can induce neurogenesis in MSCs. Direct injection of MSCs may cause tumorigenesis and an undesirable outcome. Therefore an alternative choice to overcome this

  16. The Snail transcription factor regulates the numbers of neural precursor cells and newborn neurons throughout mammalian life.

    Directory of Open Access Journals (Sweden)

    Mark A Zander

    Full Text Available The Snail transcription factor regulates diverse aspects of stem cell biology in organisms ranging from Drosophila to mammals. Here we have asked whether it regulates the biology of neural precursor cells (NPCs in the forebrain of postnatal and adult mice, taking advantage of a mouse containing a floxed Snail allele (Snailfl/fl mice. We show that when Snail is inducibly ablated in the embryonic cortex, this has long-term consequences for cortical organization. In particular, when Snailfl/fl mice are crossed to Nestin-cre mice that express Cre recombinase in embryonic neural precursors, this causes inducible ablation of Snail expression throughout the postnatal cortex. This loss of Snail causes a decrease in proliferation of neonatal cortical neural precursors and mislocalization and misspecification of cortical neurons. Moreover, these precursor phenotypes persist into adulthood. Adult neural precursor cell proliferation is decreased in the forebrain subventricular zone and in the hippocampal dentate gyrus, and this is coincident with a decrease in the number of adult-born olfactory and hippocampal neurons. Thus, Snail is a key regulator of the numbers of neural precursors and newborn neurons throughout life.

  17. The Ca2+-induced methyltransferase xPRMT1b controls neural fate in amphibian embryo.

    Science.gov (United States)

    Batut, Julie; Vandel, Laurence; Leclerc, Catherine; Daguzan, Christiane; Moreau, Marc; Néant, Isabelle

    2005-10-18

    We have previously shown that an increase in intracellular Ca2+ is both necessary and sufficient to commit ectoderm to a neural fate in Xenopus embryos. However, the relationship between this Ca2+ increase and the expression of early neural genes has yet to be defined. Using a subtractive cDNA library between untreated and caffeine-treated animal caps, i.e., control ectoderm and ectoderm induced toward a neural fate by a release of Ca2+, we have isolated the arginine N-methyltransferase, xPRMT1b, a Ca2+-induced target gene, which plays a pivotal role in this process. First, we show in embryo and in animal cap that xPRMT1b expression is Ca2+-regulated. Second, overexpression of xPRMT1b induces the expression of early neural genes such as Zic3. Finally, in the whole embryo, antisense approach with morpholino oligonucleotide against xPRMT1b impairs neural development and in animal caps blocks the expression of neural markers induced by a release of internal Ca2+. Our results implicate an instructive role of an enzyme, an arginine methyltransferase protein, in the embryonic choice of determination between epidermal and neural fate. The results presented provide insights by which a Ca2+ increase induces neural fate.

  18. Social status alters defeat-induced neural activation in Syrian hamsters.

    Science.gov (United States)

    Morrison, K E; Curry, D W; Cooper, M A

    2012-05-17

    Although exposure to social stress leads to increased depression-like and anxiety-like behavior, some individuals are more vulnerable than others to these stress-induced changes in behavior. Prior social experience is one factor that can modulate how individuals respond to stressful events. In this study, we investigated whether experience-dependent resistance to the behavioral consequences of social defeat was associated with a specific pattern of neural activation. We paired weight-matched male Syrian hamsters in daily aggressive encounters for 2 weeks, during which they formed a stable dominance relationship. We also included control animals that were exposed to an empty cage each day for 2 weeks. Twenty-four hours after the final pairing or empty cage exposure, half of the subjects were socially defeated in 3, 5-min encounters, whereas the others were not socially defeated. Twenty-four hours after social defeat, animals were tested for conditioned defeat in a 5-min social interaction test with a non-aggressive intruder. We collected brains after social defeat and processed the tissue for c-Fos immunoreactivity. We found that dominants were more likely than subordinates to counter-attack the resident aggressor during social defeat, and they showed less submissive and defensive behavior at conditioned defeat testing compared with subordinates. Also, social status was associated with distinct patterns of defeat-induced neural activation in select brain regions, including the amygdala, prefrontal cortex, hypothalamus, and lateral septum. Our results indicate that social status is an important form of prior experience that predicts both initial coping style and the degree of resistance to social defeat. Further, the differences in defeat-induced neural activation suggest possible brain regions that may control resistance to conditioned defeat in dominant individuals.

  19. Generation of primitive neural stem cells from human fibroblasts using a defined set of factors

    Directory of Open Access Journals (Sweden)

    Takumi Miura

    2015-11-01

    Full Text Available In mice, leukemia inhibitory factor (LIF-dependent primitive neural stem cells (NSCs have a higher neurogenic potential than bFGF-dependent definitive NSCs. Therefore, expandable primitive NSCs are required for research and for the development of therapeutic strategies for neurological diseases. There is a dearth of suitable techniques for the generation of human long-term expandable primitive NSCs. Here, we have described a method for the conversion of human fibroblasts to LIF-dependent primitive NSCs using a strategy based on techniques for the generation of induced pluripotent stem cells (iPSCs. These LIF-dependent induced NSCs (LD-iNSCs can be expanded for >100 passages. Long-term cultured LD-iNSCs demonstrated multipotent neural differentiation potential and could generate motor neurons and dopaminergic neurons, as well as astrocytes and oligodendrocytes, indicating a high level of plasticity. Furthermore, LD-iNSCs easily reverted to human iPSCs, indicating that LD-iNSCs are in an intermediate iPSC state. This method may facilitate the generation of patient-specific human neurons for studies and treatment of neurodegenerative diseases.

  20. Ischemia-induced neural stem/progenitor cells express pyramidal cell markers

    NARCIS (Netherlands)

    Clausen, Martijn; Nakagomi, Takayuki; Nakano-Doi, Akiko; Saino, Orie; Takata, Masashi; Taguchi, Akihiko; Luiten, Paul; Matsuyama, Tomohiro

    2011-01-01

    Adult brain-derived neural stem cells have acquired a lot of interest as an endurable neuronal cell source that can be used for central nervous system repair in a wide range of neurological disorders such as ischemic stroke. Recently, we identified injury-induced neural stem/progenitor cells in the

  1. Earthquake-induced landslide-susceptibility mapping using an artificial neural network

    Science.gov (United States)

    Lee, S.; Evangelista, D. G.

    2006-07-01

    The purpose of this study was to apply and verify landslide-susceptibility analysis techniques using an artificial neural network and a Geographic Information System (GIS) applied to Baguio City, Philippines. The 16 July 1990 earthquake-induced landslides were studied. Landslide locations were identified from interpretation of aerial photographs and field survey, and a spatial database was constructed from topographic maps, geology, land cover and terrain mapping units. Factors that influence landslide occurrence, such as slope, aspect, curvature and distance from drainage were calculated from the topographic database. Lithology and distance from faults were derived from the geology database. Land cover was identified from the topographic database. Terrain map units were interpreted from aerial photographs. These factors were used with an artificial neural network to analyze landslide susceptibility. Each factor weight was determined by a back-propagation exercise. Landslide-susceptibility indices were calculated using the back-propagation weights, and susceptibility maps were constructed from GIS data. The susceptibility map was compared with known landslide locations and verified. The demonstrated prediction accuracy was 93.20%.

  2. Earthquake-induced landslide-susceptibility mapping using an artificial neural network

    Directory of Open Access Journals (Sweden)

    S. Lee

    2006-01-01

    Full Text Available The purpose of this study was to apply and verify landslide-susceptibility analysis techniques using an artificial neural network and a Geographic Information System (GIS applied to Baguio City, Philippines. The 16 July 1990 earthquake-induced landslides were studied. Landslide locations were identified from interpretation of aerial photographs and field survey, and a spatial database was constructed from topographic maps, geology, land cover and terrain mapping units. Factors that influence landslide occurrence, such as slope, aspect, curvature and distance from drainage were calculated from the topographic database. Lithology and distance from faults were derived from the geology database. Land cover was identified from the topographic database. Terrain map units were interpreted from aerial photographs. These factors were used with an artificial neural network to analyze landslide susceptibility. Each factor weight was determined by a back-propagation exercise. Landslide-susceptibility indices were calculated using the back-propagation weights, and susceptibility maps were constructed from GIS data. The susceptibility map was compared with known landslide locations and verified. The demonstrated prediction accuracy was 93.20%.

  3. Critical Factors for Inducing Curved Somatosensory Saccades

    Directory of Open Access Journals (Sweden)

    Tamami Nakano

    2011-10-01

    Full Text Available We are able to make a saccade toward a tactile stimuli to one hand, but trajectories of many saccades curved markedly when the arms were crossed (Groh & Sparks, 2006. However, it remains unknown why some curved and others did not. We therefore examined critical factors for inducing the curved somatosensory saccades. Participants made a saccade as soon as possible from a central fixation point toward a tactile stimulus delivered to one of the two hands, and switched between arms-crossed and arms-uncrossed postures every 6 trials. Trajectories were generally straight when the arms were uncrossed, but all participants made curved saccades when the arms were crossed (12–64%. We found that the probability of curved saccades depended critically on the onset latency: the probability was less than 5% when the latency was larger than 250 ms, but the probability increased up to 70–80% when the onset latency was 160 ms. This relationship was shared across participants. The results suggest that a touch in the arms-crossed posture was always mapped to the wrong hand in the initial phase up to 160 ms, and then remapped to the correct hand during the next 100 ms by some fundamental neural mechanisms shared across participants.

  4. Neural Correlates of Stress-Induced and Cue-Induced Drug Craving: Influences of Sex and Cocaine Dependence

    National Research Council Canada - National Science Library

    Potenza, Marc N; Hong, Kwang-ik Adam; Lacadie, Cheryl M; Fulbright, Robert K; Tuit, Keri L; Sinha, Rajita

    2012-01-01

    .... Objective:Although stress and drug cue exposure each increase drug craving and contribute to relapse in cocaine dependence, no previous research has directly examined the neural correlates of stress-induced...

  5. Gene expression profiling of human neural progenitor cells following the serum-induced astrocyte differentiation.

    Science.gov (United States)

    Obayashi, Shinya; Tabunoki, Hiroko; Kim, Seung U; Satoh, Jun-ichi

    2009-05-01

    Neural stem cells (NSC) with self-renewal and multipotent properties could provide an ideal cell source for transplantation to treat spinal cord injury, stroke, and neurodegenerative diseases. However, the majority of transplanted NSC and neural progenitor cells (NPC) differentiate into astrocytes in vivo under pathological environments in the central nervous system, which potentially cause reactive gliosis. Because the serum is a potent inducer of astrocyte differentiation of rodent NPC in culture, we studied the effect of the serum on gene expression profile of cultured human NPC to identify the gene signature of astrocyte differentiation of human NPC. Human NPC spheres maintained in the serum-free culture medium were exposed to 10% fetal bovine serum (FBS) for 72 h, and processed for analyzing on a Whole Human Genome Microarray of 41,000 genes, and the microarray data were validated by real-time RT-PCR. The serum elevated the levels of expression of 45 genes, including ID1, ID2, ID3, CTGF, TGFA, METRN, GFAP, CRYAB and CSPG3, whereas it reduced the expression of 23 genes, such as DLL1, DLL3, PDGFRA, SOX4, CSPG4, GAS1 and HES5. Thus, the serum-induced astrocyte differentiation of human NPC is characterized by a counteraction of ID family genes on Delta family genes. Coimmunoprecipitation analysis identified ID1 as a direct binding partner of a proneural basic helix-loop-helix (bHLH) transcription factor MASH1. Luciferase assay indicated that activation of the DLL1 promoter by MASH1 was counteracted by ID1. Bone morphogenetic protein 4 (BMP4) elevated the levels of ID1 and GFAP expression in NPC under the serum-free culture conditions. Because the serum contains BMP4, these results suggest that the serum factor(s), most probably BMP4, induces astrocyte differentiation by upregulating the expression of ID family genes that repress the proneural bHLH protein-mediated Delta expression in human NPC.

  6. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    Science.gov (United States)

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes. PMID:27212953

  7. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins.

    Science.gov (United States)

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes.

  8. Reprogramming of adult human neural stem cells into induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    XIE Li-qian; SUN Hua-ping; WANG Tian; TANG Hai-liang; WANG Pu; ZHU Jian-hong; YAO Zheng-wei

    2013-01-01

    Background Since an effective method for generating induced pluripotent stem cells (iPSCs) from human neural stem cells (hNSCs) can offer us a promising tool for studying brain diseases,here we reported direct reprogramming of adult hNSCs into iPSCs by retroviral transduction of four defined factors.Methods NSCs were successfully isolated and cultured from the hippocampus tissue of epilepsy patients.When combined with four factors (OCT3/4,SOX2,KLF4,and c-MYC),iPSCs colonies were successfully obtained.Results Morphological characterization and specific genetic expression confirmed that these hNSCs-derived iPSCs showed embryonic stem cells-like properties,which include the ability to differentiate into all three germ layers both in vitro and in vivo.Conclusion Our method would be useful for generating human iPSCs from NSCs and provide an important tool for studying neurological diseases.

  9. BMP-induced reprogramming of the neural retina into retinal pigment epithelium requires Wnt signalling

    Directory of Open Access Journals (Sweden)

    Jörg Steinfeld

    2017-07-01

    Full Text Available In vertebrates, the retinal pigment epithelium (RPE and photoreceptors of the neural retina (NR comprise a functional unit required for vision. During vertebrate eye development, a conversion of the RPE into NR can be induced by growth factors in vivo at optic cup stages, but the reverse process, the conversion of NR tissue into RPE, has not been reported. Here, we show that bone morphogenetic protein (BMP signalling can reprogram the NR into RPE at optic cup stages in chick. Shortly after BMP application, expression of Microphthalmia-associated transcription factor (Mitf is induced in the NR and selective cell death on the basal side of the NR induces an RPE-like morphology. The newly induced RPE differentiates and expresses Melanosomalmatrix protein 115 (Mmp115 and RPE65. BMP-induced Wnt2b expression is observed in regions of the NR that become pigmented. Loss of function studies show that conversion of the NR into RPE requires both BMP and Wnt signalling. Simultaneous to the appearance of ectopic RPE tissue, BMP application reprogrammed the proximal RPE into multi-layered retinal tissue. The newly induced NR expresses visual segment homeobox-containing gene (Vsx2, and the ganglion and photoreceptor cell markers Brn3α and Visinin are detected. Our results show that high BMP concentrations are required to induce the conversion of NR into RPE, while low BMP concentrations can still induce transdifferentiation of the RPE into NR. This knowledge may contribute to the development of efficient standardized protocols for RPE and NR generation for cell replacement therapies.

  10. Long-term culture and differentiation of CNS precursors derived from anterior human neural rosettes following exposure to ventralizing factors

    Energy Technology Data Exchange (ETDEWEB)

    Colleoni, Silvia, E-mail: silviacolleoni@avantea.it [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy); Galli, Cesare [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy); Dipartimento Clinico Veterinario, Universita di Bologna, Via Tolara di Sopra 50, 40064 Ozzano Emilia (Italy); Giannelli, Serena G. [Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan (Italy); Armentero, Marie-Therese; Blandini, Fabio [Laboratory of Functional Neurochemistry, Interdepartmental Research Center for Parkinson' s Disease, Neurological Institute C. Mondino, Via Mondino 2, 27100 Pavia (Italy); Broccoli, Vania, E-mail: broccoli.vania@hsr.it [Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan (Italy); Lazzari, Giovanna, E-mail: giovannalazzari@avantea.it [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy)

    2010-04-15

    In this study we demonstrated that neural rosettes derived from human ES cells can give rise either to neural crest precursors, following expansion in presence of bFGF and EGF, or to dopaminergic precursors after exposure to ventralizing factors Shh and FGF8. Both regionalised precursors are capable of extensive proliferation and differentiation towards the corresponding terminally differentiated cell types. In particular, peripheral neurons, cartilage, bone, smooth muscle cells and also pigmented cells were obtained from neural crest precursors while tyrosine hydroxylase and Nurr1 positive dopaminergic neurons were derived from FGF8 and Shh primed rosette cells. Gene expression and immunocytochemistry analyses confirmed the expression of dorsal and neural crest genes such as Sox10, Slug, p75, FoxD3, Pax7 in neural precursors from bFGF-EGF exposed rosettes. By contrast, priming of rosettes with FGF8 and Shh induced the expression of dopaminergic markers Engrailed1, Pax2, Pitx3, floor plate marker FoxA2 and radial glia markers Blbp and Glast, the latter in agreement with the origin of dopaminergic precursors from floor plate radial glia. Moreover, in vivo transplant of proliferating Shh/FGF8 primed precursors in parkinsonian rats demonstrated engraftment and terminal dopaminergic differentiation. In conclusion, we demonstrated the derivation of long-term self-renewing precursors of selected regional identity as potential cell reservoirs for cell therapy applications, such as CNS degenerative diseases, or for the development of toxicological tests.

  11. Regulation of endogenous neural stem/progenitor cells for neural repair - factors that promote neurogenesis and gliogenesis in the normal and damaged brain

    Directory of Open Access Journals (Sweden)

    Kimberly eChristie

    2013-01-01

    Full Text Available Neural stem/precursor cells in the adult brain reside in the subventricular zone (SVZ of the lateral ventricles and the subgranular zone (SGZ of the dentate gyrus in the hippocampus. These cells primarily generate neuroblasts that normally migrate to the olfactory bulb and the dentate granule cell layer respectively. Following brain damage, such as traumatic brain injury, ischemic stroke or in degenerative disease models, neural precursor cells from the SVZ in particular, can migrate from their normal route along the rostral migratory stream to the site of neural damage. This neural precursor cell response to neural damage is mediated by release of endogenous factors, including cytokines and chemokines produced by the inflammatory response at the injury site, and by the production of growth and neurotrophic factors. Endogenous hippocampal neurogenesis is frequently also directly or indirectly affected by neural damage. Administration of a variety of factors that regulate different aspects of neural stem/precursor biology often leads to improved functional motor and/or behavioural outcomes. Such factors can target neural stem/precursor proliferation, survival, migration and differentiation into appropriate neuronal or glial lineages. Newborn cells also need to subsequently survive and functionally integrate into extant neural circuitry, which may be the major bottleneck to the current therapeutic potential of neural stem/precursor cells. This review will cover the effects of a range of intrinsic and extrinsic factors that regulate neural stem /precursor cell functions. In particular it focuses on factors that may be harnessed to enhance the endogenous neural stem/precursor cell response to neural damage, highlighting those that have already shown evidence of preclinical effectiveness and discussing others that warrant further preclinical investigation.

  12. In vitro induced dopaminergic differentiation of expanded rat mesencephalic neural stem cell

    Institute of Scientific and Technical Information of China (English)

    ZHENG Min; WANG Dongmei; JIAO Wenchang; LI Haiming; ZHAO Lianxu; BAI Chixian; WANG Yaping; PEI Xuetao

    2003-01-01

    Neural stem cell (NSC) is the progenitor of the neural system with the character of self-renew and having the potential to differentiate into all the phenotypes in the central nervous system (CNS). NSC may serve as a source of cell transplantation for the treatment of neurodegenerative diseases to replace degenerative neurons. In this study, NSCs derived from E12.5 rat mesencephalon were maintained and expanded using a serum-free defined medium containing basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF). While proliferating, the cells were immunoreactive for nestin and remained multipotent to generate neurons, astrocytes, and oligodendrocytes. After 15 times passage the total number of the cell expanded about 2.4×104 fold. Compared with untreated cultures, ascorbic acid (AA) treatment led to more dopaminergic (DAergic) differentitiation as indicated by the expression of tyrosine hydroxylase (TH). With the concentration increasing, more TH+ neurons were obtained. 100 μmol/L AA could lead to a increase more than 20-fold, and a concentration of 10 μmol/L could lead to nearly 5-fold increase in TH+ cells. However, the ratio of TH+ cells was not improved any longer with the AA increasing above the concentration of 100 μmol/L. The results demonstrate that expanded NSCs can be induced to differentiate into dopamine neurons in vitro, which can provide enough cell population for the cell transplantation, as a main intervention for the neurodegenerative diseases such as Parkinson's disease.

  13. Noise-Induced Hearing Loss (NIHL Prediction in Humans Using a Modified Back Propagation Neural Network

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair Rehman

    2011-01-01

    Full Text Available Noise-Induced Hearing Loss (NIHL has become a major source of health problem in industrial workers due to continuous exposure to high frequency sounds emitting from the machines. In the past, several studies have been carried-out to identify NIHL industrial workers. Unfortunately, these studies neglected some important factors that directly affect hearing ability in human. Artificial Neural Network (ANN provides very effective way to predict hearing loss in humans. However, the training process for an ANN required the designers to arbitrarily select parameters such as network topology, initial weights and biases, learning rate value, the activation function, value for gain in activation function and momentum. An improper choice of any of these parameters can result in slow convergence or even network paralysis, where the training process comes to a standstill or get stuck at local minima. Therefore, this current study focuses on proposing a new framework on using Gradient Descent Back Propagation Neural Network model with an improvement on the momentum value to identify the important factors that directly affect the hearing ability of industrial workers. Results from the prediction will be used in determining the environmental health hazards which affect the workers health.

  14. Neural basis of scientific innovation induced by heuristic prototype.

    Directory of Open Access Journals (Sweden)

    Junlong Luo

    Full Text Available A number of major inventions in history have been based on bionic imitation. Heuristics, by applying biological systems to the creation of artificial devices and machines, might be one of the most critical processes in scientific innovation. In particular, prototype heuristics propositions that innovation may engage automatic activation of a prototype such as a biological system to form novel associations between a prototype's function and problem-solving. We speculated that the cortical dissociation between the automatic activation and forming novel associations in innovation is critical point to heuristic creativity. In the present study, novel and old scientific innovations (NSI and OSI were selected as experimental materials in using learning-testing paradigm to explore the neural basis of scientific innovation induced by heuristic prototype. College students were required to resolve NSI problems (to which they did not know the answers and OSI problems (to which they knew the answers. From two fMRI experiments, our results showed that the subjects could resolve NSI when provided with heuristic prototypes. In Experiment 1, it was found that the lingual gyrus (LG; BA18 might be related to prototype heuristics in college students resolving NSI after learning a relative prototype. In Experiment 2, the LG (BA18 and precuneus (BA31 were significantly activated for NSI compared to OSI when college students learned all prototypes one day before the test. In addition, the mean beta-values of these brain regions of NSI were all correlated with the behavior accuracy of NSI. As our hypothesis indicated, the findings suggested that the LG might be involved in forming novel associations using heuristic information, while the precuneus might be involved in the automatic activation of heuristic prototype during scientific innovation.

  15. The neural correlates of crowding-induced changes in appearance

    National Research Council Canada - National Science Library

    Anderson, Elaine J; Dakin, Steven C; Schwarzkopf, D Samuel; Rees, Geraint; Greenwood, John A

    2012-01-01

    .... Despite its severity, little is known about the cortical locus of crowding. Here, we examined the neural correlates of crowding by combining event-related fMRI adaptation with a change-detection paradigm...

  16. Weight-decay induced phase transitions in multilayer neural networks

    NARCIS (Netherlands)

    Ahr, M.; Biehl, M.; Schlösser, E.

    1999-01-01

    We investigate layered neural networks with differentiable activation function and student vectors without normalization constraint by means of equilibrium statistical physics. We consider the learning of perfectly realizable rules and find that the length of student vectors becomes infinite, unless

  17. Cold-inducible RNA binding protein (CIRP, a novel XTcf-3 specific target gene regulates neural development in Xenopus

    Directory of Open Access Journals (Sweden)

    Wedlich Doris

    2008-08-01

    Full Text Available Abstract Background As nuclear mediators of wnt/β-catenin signaling, Lef/Tcf transcription factors play important roles in development and disease. Although it is well established, that the four vertebrate Lef/Tcfs have unique functional properties, most studies unite Lef-1, Tcf-1, Tcf-3 and Tcf-4 and reduce their function to uniformly transduce wnt/β-catenin signaling for activating wnt target genes. In order to discriminate target genes regulated by XTcf-3 from those regulated by XTcf-4 or Lef/Tcfs in general, we performed a subtractive screen, using neuralized Xenopus animal cap explants. Results We identified cold-inducible RNA binding protein (CIRP as novel XTcf-3 specific target gene. Furthermore, we show that knockdown of XTcf-3 by injection of an antisense morpholino oligonucleotide results in a general broadening of the anterior neural tissue. Depletion of XCIRP by antisense morpholino oligonucleotide injection leads to a reduced stability of mRNA and an enlargement of the anterior neural plate similar to the depletion of XTcf-3. Conclusion Distinct steps in neural development are differentially regulated by individual Lef/Tcfs. For proper development of the anterior brain XTcf-3 and the Tcf-subtype specific target XCIRP appear indispensable. Thus, regulation of anterior neural development, at least in part, depends on mRNA stabilization by the novel XTcf-3 target gene XCIRP.

  18. Prolonged propagation of rat neural stem cells relies on inhibiting autocrine/paracrine bone morphogenetic protein and platelet derived growth factor signals

    Institute of Scientific and Technical Information of China (English)

    Yirui Sun; Liangfu Zhou; Xing Wu; Hua Liu; Qiang Yuan; Ying Mao; Jin Hu

    2011-01-01

    Continuous expansion of rat neural stem cell lines has not been achieved due to proliferation arrest and spontaneous differentiation in vitro. In the current study, neural precursor cells derived from the subventricular zone of adult rats spontaneously underwent astroglial and oligodendroglial differentiation after limited propagation. This differentiation was largely induced by autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signals. The results showed that, by inhibiting bone morphogenetic protein and platelet derived growth factor signals, adult rat neural precursor cells could be extensively cultured in vitro as tripotent stem cell lines. In addition to adult rat neural stem cells, we found that bone morphogenetic protein antagonists can promote the proliferation of human neural stem cells. Therefore, the present findings illustrated the role of autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signaling in determining neural stem cell self-renewal and differentiation. By antagonizing both signals, the long-term propagation of rat neural stem cell lines can be achieved.

  19. Neural Degeneration in the Retina of the Streptozotocin-Induced Type 1 Diabetes Model

    Directory of Open Access Journals (Sweden)

    Yoko Ozawa

    2011-01-01

    Full Text Available Diabetic retinopathy, a vision-threatening disease, has been regarded as a vascular disorder. However, impaired oscillatory potentials (OPs in the electroretinogram (ERG and visual dysfunction are recorded before severe vascular lesions appear. Here, we review the molecular mechanisms underlying the retinal neural degeneration observed in the streptozotocin-(STZ- induced type 1 diabetes model. The renin-angiotensin system (RAS and reactive oxygen species (ROS both cause OP impairment and reduced levels of synaptophysin, a synaptic vesicle protein for neurotransmitter release, most likely through excessive protein degradation by the ubiquitin-proteasome system. ROS also decrease brain-derived neurotrophic factor (BDNF and inner retinal neuronal cells. The influence of both RAS and ROS on synaptophysin suggests that RAS-ROS crosstalk occurs in the diabetic retina. Therefore, suppressors of RAS or ROS, such as angiotensin II type 1 receptor blockers or the antioxidant lutein, respectively, are potential candidates for neuroprotective and preventive therapies to improve the visual prognosis.

  20. Gene expression in retinoic acid-induced neural tube defects A cDNA mieroarray analysis

    Institute of Scientific and Technical Information of China (English)

    Xiaodong Long; Zhong Yang; Yi Zeng; Hongli Li; Yangyun Han; Chao You

    2009-01-01

    BACKGROUND: Neural tube defects can be induced by abnormal factors in vivo or in vitro during development. However, the molecular mechanisms of neural tube defect induction, and the related gene expression and regulation are still unknown.OBJECTIVE: To compare the differences in gene expression between normal embryos and those with neural tube defects.DESIGN, TIME AND SETTING: A neural development study was performed at the Department of Neurobiology, Third Military Medical University of Chinese PLA between January 2006 and October 2007.MATERIALS: Among 120 adult Kunming mice, 60 pregnant mice were randomly and evenly divided into a retinoic acid group (n = 30) and a normal control group (n =30). The retinoic acid was produced by Sigma, USA, the gene microarray by the Amersham Pharmacia Company, Hong Kong, and the gene sequence was provided by the Incyte database, USA.METHODS: Retinoic acid was administered to prepare models of neural tube defects, and corn oil was similady administered to the normal control group. Total RNA was extracted from embryonic tissue of the two groups using a Trizol kit, and a cDNA microarray containing 1 100 known genes was used to compare differences in gene expression between the normal control group and the retinoic acid group on embryonic (E) clay 10.5 and 11.5. Several differentially expressed genes were randomly selected from the two groups for Northern blotting, to verify the results of the cDNA microarray.MAIN OUTCOME MEASURES: Morphological changes and differential gene expression between the normal control group and the retinoic acid group.RESULTS: Anatomical microscopy demonstrated that an intact closure of the brain was formed in the normal mouse embryos by days E10.5 and E11.5. The cerebral appearance was full and smooth, and the surface of the spine was intact. However, in the retinoic acid group on days E10.5 and E11.5, there were more dead embryos. Morphological malformations typically included non-closure at the top of

  1. Alcohol-Induced Molecular Dysregulation in Human Embryonic Stem Cell-Derived Neural Precursor Cells

    Science.gov (United States)

    Kim, Yi Young; Roubal, Ivan; Lee, Youn Soo; Kim, Jin Seok; Hoang, Michael; Mathiyakom, Nathan; Kim, Yong

    2016-01-01

    Adverse effect of alcohol on neural function has been well documented. Especially, the teratogenic effect of alcohol on neurodevelopment during embryogenesis has been demonstrated in various models, which could be a pathologic basis for fetal alcohol spectrum disorders (FASDs). While the developmental defects from alcohol abuse during gestation have been described, the specific mechanisms by which alcohol mediates these injuries have yet to be determined. Recent studies have shown that alcohol has significant effect on molecular and cellular regulatory mechanisms in embryonic stem cell (ESC) differentiation including genes involved in neural development. To test our hypothesis that alcohol induces molecular alterations during neural differentiation we have derived neural precursor cells from pluripotent human ESCs in the presence or absence of ethanol treatment. Genome-wide transcriptomic profiling identified molecular alterations induced by ethanol exposure during neural differentiation of hESCs into neural rosettes and neural precursor cell populations. The Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis on significantly altered genes showed potential ethanol’s effect on JAK-STAT signaling pathway, neuroactive ligand-receptor interaction, Toll-like receptor (TLR) signaling pathway, cytokine-cytokine receptor interaction and regulation of autophagy. We have further quantitatively verified ethanol-induced alterations of selected candidate genes. Among verified genes we further examined the expression of P2RX3, which is associated with nociception, a peripheral pain response. We found ethanol significantly reduced the level of P2RX3 in undifferentiated hESCs, but induced the level of P2RX3 mRNA and protein in hESC-derived NPCs. Our result suggests ethanol-induced dysregulation of P2RX3 along with alterations in molecules involved in neural activity such as neuroactive ligand-receptor interaction may be a molecular event

  2. Prenatal exposure of ethanol induces increased glutamatergic neuronal differentiation of neural progenitor cells

    Directory of Open Access Journals (Sweden)

    Han Seol-Heui

    2010-11-01

    Full Text Available Abstract Background Prenatal ethanol exposure during pregnancy induces a spectrum of mental and physical disorders called fetal alcohol spectrum disorder (FASD. The central nervous system is the main organ influenced by FASD, and neurological symptoms include mental retardation, learning abnormalities, hyperactivity and seizure susceptibility in childhood along with the microcephaly. In this study, we examined whether ethanol exposure adversely affects the proliferation of NPC and de-regulates the normal ratio between glutamatergic and GABAergic neuronal differentiation using primary neural progenitor culture (NPC and in vivo FASD models. Methods Neural progenitor cells were cultured from E14 embryo brain of Sprague-Dawley rat. Pregnant mice and rats were treated with ethanol (2 or 4 g/kg/day diluted with normal saline from E7 to E16 for in vivo FASD animal models. Expression level of proteins was investigated by western blot analysis and immunocytochemical assays. MTT was used for cell viability. Proliferative activity of NPCs was identified by BrdU incorporation, immunocytochemistry and FACS analysis. Results Reduced proliferation of NPCs by ethanol was demonstrated using BrdU incorporation, immunocytochemistry and FACS analysis. In addition, ethanol induced the imbalance between glutamatergic and GABAergic neuronal differentiation via transient increase in the expression of Pax6, Ngn2 and NeuroD with concomitant decrease in the expression of Mash1. Similar pattern of expression of those transcription factors was observed using an in vivo model of FASD as well as the increased expression of PSD-95 and decreased expression of GAD67. Conclusions These results suggest that ethanol induces hyper-differentiation of glutamatergic neuron through Pax6 pathway, which may underlie the hyper-excitability phenotype such as hyperactivity or seizure susceptibility in FASD patients.

  3. Punicalagin exerts protective effect against high glucose-induced cellular stress and neural tube defects.

    Science.gov (United States)

    Zhong, Jianxiang; Reece, E Albert; Yang, Peixin

    2015-11-13

    Maternal diabetes-induced birth defects remain a significant health problem. Studying the effect of natural compounds with antioxidant properties and minimal toxicities on diabetic embryopathy may lead to the development of new and safe dietary supplements. Punicalagin is a primary polyphenol found in pomegranate juice, which possesses antioxidant, anti-inflammatory and anti-tumorigenic properties, suggesting a protective effect of punicalagin on diabetic embryopathy. Here, we examined whether punicalagin could reduce high glucose-induced neural tube defects (NTDs), and if this rescue occurs through blockage of cellular stress and caspase activation. Embryonic day 8.5 (E8.5) mouse embryos were cultured for 24 or 36 h with normal (5 mM) glucose or high glucose (16.7 mM), in presence or absence of 10 or 20 μM punicalagin. 10 μM punicalagin slightly reduced NTD formation under high glucose conditions; however, 20 μM punicalagin significantly inhibited high glucose-induced NTD formation. Punicalagin suppressed high glucose-induced lipid peroxidation marker 4-hydroxynonenal, nitrotyrosine-modified proteins, and lipid peroxides. Moreover, punicalagin abrogated endoplasmic reticulum stress by inhibiting phosphorylated protein kinase ribonucleic acid (RNA)-like ER kinase (p-PERK), phosphorylated inositol-requiring protein-1α (p-IRE1α), phosphorylated eukaryotic initiation factor 2α (p-eIF2α), C/EBP-homologous protein (CHOP), binding immunoglobulin protein (BiP) and x-box binding protein 1 (XBP1) mRNA splicing. Additionally, punicalagin suppressed high glucose-induced caspase 3 and caspase 8 cleavage. Punicalagin reduces high glucose-induced NTD formation by blocking cellular stress and caspase activation. These observations suggest punicalagin supplements could mitigate the teratogenic effects of hyperglycemia in the developing embryo, and possibly prevent diabetes-induced NTDs.

  4. Coherence Resonance and Noise-Induced Synchronization in Hindmarsh-Rose Neural Network with Different Topologies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, we investigate coherence resonance (CR) and noise-induced synchronization in Hindmarsh-Rose (HR) neural network with three different types of topologies: regular, random, and small-world. It is found that the additive noise can induce CR in HR neural network with different topologies and its coherence is optimized by a proper noise level. It is also found that as coupling strength increases the plateau in the measure of coherence curve becomes broadened and the effects of network topology is more pronounced simultaneously. Moreover, we find that increasing tie probability p of the network topology leads to an enhancement of noise-induced synchronization in HR neurons network.

  5. chinaIn vitro differentiation of mesencephalic neural stem cells induced by glial-derived neurotrophic factor under hypoxia%低氧环境下胶质源性神经营养因子体外诱导中脑神经干细胞的分化

    Institute of Scientific and Technical Information of China (English)

    丁继固; 丁文杰

    2011-01-01

    BACKGROUND: During neural stem cell transplantation in the treatment of Parkinson's disease, the number of transplantedcells and differentiation ratio of dopaminergic neurons must be resolved. Effective in vitro proliferation of neural stem cells andlarge amount of directed differentiation of dopaminergic neurons are the key to solve above-mentioned problems.OBJECTIVE: To investigate the differentiation of mesencephalic neural stem cells into dopaminergic neurons during the hypoxiainduced by glial cell line-derived neurotrophic factor (GDNF) in vitro.METHODS: Ventral midbrain tissue isolated from embryonic mice of pregnant 12 days was made into single cell suspension andcultured in non-serum medium containing basic fibroblast growth factor (bFGF) and B27, and then proliferated under normoxia orhypoxia for5-7 days followed by incubation in DMEM/F12 medium containing 10% fetal bovine serum or 10% fetal bovine serum+ 1 g/L GDNF.RESULTS AND CONCLUSION: Under the hypoxia environment, the number of dopaminergic neurons differentiated frommesencephalic neura I stem cells especially induced by GDNF was higher than that under normoxia. It indicated that under thehypoxia environment, GDNF can induce mesencephalic neural stem cells differentiating into dopaminergic neurons with enoughquantity, mature shape and function.%背景:有效的神经干细胞体外增殖与多巴胺能神经元的定向诱导分化是神经干细胞移植治疗帕金森病的关键所在.目的:观察低氧条件下胶质源性神经营养因子体外诱导中脑源性神经干细胞向多巴胺能神经元的分化.方法:体外分离培养孕12 d胚鼠腹侧中脑组织,制成单细胞悬液,在含碱性成纤维细胞生长因子和B27的无血清培养基中培养并传代,分别置于常氧(体积分数21%O2)或低氧(体积分数3%O2)环境下增殖5~7 d后,接种于含体积分数10%胎牛血清的DMEM/F12培养基,或含体积分数10%胎牛血清的DMEM/F12+1 μg/L胶质源性神经营养

  6. Neural Stem Cell Transplantation Induces Stroke Recovery by Upregulating Glutamate Transporter GLT-1 in Astrocytes.

    Science.gov (United States)

    Bacigaluppi, Marco; Russo, Gianluca Luigi; Peruzzotti-Jametti, Luca; Rossi, Silvia; Sandrone, Stefano; Butti, Erica; De Ceglia, Roberta; Bergamaschi, Andrea; Motta, Caterina; Gallizioli, Mattia; Studer, Valeria; Colombo, Emanuela; Farina, Cinthia; Comi, Giancarlo; Politi, Letterio Salvatore; Muzio, Luca; Villani, Claudia; Invernizzi, Roberto William; Hermann, Dirk Matthias; Centonze, Diego; Martino, Gianvito

    2016-10-12

    plasticity and to induce long-term functional recovery. The observed therapeutic effect of neural precursor cells seems to underlie their capacity to upregulate the glial glutamate transporter on astrocytes through the vascular endothelial growth factor inducing favorable changes in the electrical and molecular stroke microenvironment. Cell-based approaches able to influence plasticity seem particularly suited to favor poststroke recovery. Copyright © 2016 Bacigaluppi et al.

  7. Neural Stem Cell Transplantation Induces Stroke Recovery by Upregulating Glutamate Transporter GLT-1 in Astrocytes

    Science.gov (United States)

    Russo, Gianluca Luigi; Peruzzotti-Jametti, Luca; Rossi, Silvia; Sandrone, Stefano; Butti, Erica; De Ceglia, Roberta; Bergamaschi, Andrea; Motta, Caterina; Gallizioli, Mattia; Studer, Valeria; Colombo, Emanuela; Farina, Cinthia; Comi, Giancarlo; Politi, Letterio Salvatore; Muzio, Luca; Villani, Claudia; Invernizzi, Roberto William; Hermann, Dirk Matthias; Centonze, Diego

    2016-01-01

    axonal rewiring and dendritic plasticity and to induce long-term functional recovery. The observed therapeutic effect of neural precursor cells seems to underlie their capacity to upregulate the glial glutamate transporter on astrocytes through the vascular endothelial growth factor inducing favorable changes in the electrical and molecular stroke microenvironment. Cell-based approaches able to influence plasticity seem particularly suited to favor poststroke recovery. PMID:27733606

  8. Conversion of Human Fibroblasts to Stably Self-Renewing Neural Stem Cells with a Single Zinc-Finger Transcription Factor

    Directory of Open Access Journals (Sweden)

    Ebrahim Shahbazi

    2016-04-01

    Full Text Available Direct conversion of somatic cells into neural stem cells (NSCs by defined factors holds great promise for mechanistic studies, drug screening, and potential cell therapies for different neurodegenerative diseases. Here, we report that a single zinc-finger transcription factor, Zfp521, is sufficient for direct conversion of human fibroblasts into long-term self-renewable and multipotent NSCs. In vitro, Zfp521-induced NSCs maintained their characteristics in the absence of exogenous factor expression and exhibited morphological, molecular, developmental, and functional properties that were similar to control NSCs. In addition, the single-seeded induced NSCs were able to form NSC colonies with efficiency comparable with control NSCs and expressed NSC markers. The converted cells were capable of surviving, migrating, and attaining neural phenotypes after transplantation into neonatal mouse and adult rat brains, without forming tumors. Moreover, the Zfp521-induced NSCs predominantly expressed rostral genes. Our results suggest a facilitated approach for establishing human NSCs through Zfp521-driven conversion of fibroblasts.

  9. The Protective Effect of Melatonin on Neural Stem Cell against LPS-Induced Inflammation

    Directory of Open Access Journals (Sweden)

    Juhyun Song

    2015-01-01

    Full Text Available Stem cell therapy for tissue regeneration has several limitations in the fact that transplanted cells could not survive for a long time. For solving these limitations, many studies have focused on the antioxidants to increase survival rate of neural stem cells (NSCs. Melatonin, an antioxidant synthesized in the pineal gland, plays multiple roles in various physiological mechanisms. Melatonin exerts neuroprotective effects in the central nervous system. To determine the effect of melatonin on NSCs which is in LPS-induced inflammatory stress state, we first investigated nitric oxide (NO production and cytotoxicity using Griess reagent assays, LDH assay, and neurosphere counting. Also, we investigated the effect of melatonin on NSCs by measuring the mRNA levels of SOX2, TLX, and FGFR-2. In addition, western blot analyses were performed to examine the activation of PI3K/Akt/Nrf2 signaling in LPS-treated NSCs. In the present study, we suggested that melatonin inhibits NO production and protects NSCs against LPS-induced inflammatory stress. In addition, melatonin promoted the expression of SOX2 and activated the PI3K/Akt/Nrf2 signaling under LPS-induced inflammation condition. Based on our results, we conclude that melatonin may be an important factor for the survival and proliferation of NSCs in neuroinflammatory diseases.

  10. Human neural stem cell-induced endothelial morphogenesis requires autocrine/paracrine and juxtacrine signaling

    Science.gov (United States)

    Chou, Chung-Hsing; Modo, Michel

    2016-01-01

    Transplanted neural stem cells (NSC) interact with the host brain microenvironment. A neovascularization is commonly observed in the vicinity of the cell deposit, which is correlated with behavioral improvements. To elucidate the signaling mechanisms between human NSCs and endothelial cells (ECs), these were cocultured in an in vitro model in which NSC-induced endothelial morphogenesis produced a neurovascular environment. Soluble (autocrine/paracrine) and contact–mediated (juxtacrine) signaling molecules were evaluated for two conditionally immortalized fetal NSC lines derived from the cortical anlage (CTXOE03) and ganglionic eminence (STROC05), as well as an adult EC line (D3) derived from the cerebral microvasculature of a hippocampal biopsy. STROC05 were 4 times as efficient to induce endothelial morphogenesis compared to CTXOE03. The cascade of reciprocal interactions between NSCs and ECs in this process was determined by quantifying soluble factors, receptor mapping, and immunocytochemistry for extracellular matrix molecules. The mechanistic significance of these was further evaluated by pharmacological blockade. The sequential cell-specific regulation of autocrine/paracrine and juxtacrine signaling accounted for the differential efficiency of NSCs to induce endothelial morphogenesis. These in vitro studies shed new light on the reciprocal interactions between NSCs and ECs, which are pivotal for our mechanistic understanding of the efficacy of NSC transplantation. PMID:27374240

  11. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    Directory of Open Access Journals (Sweden)

    Liu-lin Xiong

    2016-01-01

    Full Text Available Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 µg/L to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  12. Artificial neural network in studying factors of hepatic cancer recurrence after hepatectomy

    Institute of Scientific and Technical Information of China (English)

    HE Jia; HE Xian-min; ZHANG Zhi-jian

    2002-01-01

    Objective: To explore the affecting factors of liver cancer recurrence after hepatectomy. Methods:The BP artificial neural network - Cox regression was introduced to analyze the factors of recurrence in1 457 patients. Results: The affecting factors statistically significant to liver cancer prognosis was selected.There were 18 factors to be selected by uni-factor analysis, and 9 factors to be selected by multi-factor analysis. Conclusion: The 9 factors selected can be used as important indexes to evaluate the recurrence of liver cancer after hepatectomy. The artificial neural network is a better method to analyze the clinical data, which provides scientific and objective data for evaluating prognosis of liver cancer.

  13. Global Burden of Neural Tube Defects, Risk Factors, and Prevention

    Directory of Open Access Journals (Sweden)

    Joseph E

    2014-11-01

    Full Text Available Neural tube defects (NTDs, serious birth defects of the brain and spine usually resulting in death or paralysis, affect an estimated 300,000 births each year worldwide. Although the majority of NTDs are preventable with adequate folic acid consumption during the preconception period and throughout the first few weeks of gestation, many populations, in particular those in low and middle resource settings, do not have access to fortified foods or vitamin supplements containing folic acid. Further, accurate birth defects surveillance data, which could help inform mandatory fortification and other NTD prevention initiatives, are lacking in many of these settings. The burden of birth defects in South East Asia is among the highest in the world. Expanding global neural tube defects prevention initiatives can support the achievement of the United Nations Millennium Development Goal 4 to reduce child mortality, a goal which many countries in South East Asia are currently not poised to reach, and the 63rd World Health Assembly Resolution on birth defects. More work is needed to develop and implement mandatory folic acid fortification policies, as well as supplementation programs in countries where the reach of fortification is limited.

  14. Sox2, a key factor in the regulation of pluripotency and neural differentiation

    Institute of Scientific and Technical Information of China (English)

    Shuchen; Zhang; Wei; Cui

    2014-01-01

    Sex determining region Y-box 2(Sox2), a member of the SoxB1 transcription factor family, is an important transcriptional regulator in pluripotent stem cells(PSCs). Together with octamer-binding transcription factor 4 and Nanog, they co-operatively control gene expression in PSCs and maintain their pluripotency. Furthermore, Sox2 plays an essential role in somatic cell reprogram-ming, reversing the epigenetic configuration of differ-entiated cells back to a pluripotent embryonic state. In addition to its role in regulation of pluripotency, Sox2 is also a critical factor for directing the differentiation of PSCs to neural progenitors and for maintaining the properties of neural progenitor stem cells. Here, we review recent findings concerning the involvement of Sox2 in pluripotency, somatic cell reprogramming and neural differentiation as well as the molecular mecha-nisms underlying these roles.

  15. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    Directory of Open Access Journals (Sweden)

    Hayato Fukusumi

    2016-01-01

    Full Text Available Human neural progenitor cells (hNPCs have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi. Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes.

  16. The Non-Survival Effects of Glial Cell Line-Derived Neurotrophic Factor on Neural Cells

    Directory of Open Access Journals (Sweden)

    Daniel Cortés

    2017-08-01

    Full Text Available Glial cell line-derived neurotrophic factor (GDNF was first characterized as a survival-promoting molecule for dopaminergic neurons (DANs. Afterwards, other cells were also discovered to respond to GDNF not only as a survival factor but also as a protein supporting other cellular functions, such as proliferation, differentiation, maturation, neurite outgrowth and other phenomena that have been less studied than survival and are now more extendedly described here in this review article. During development, GDNF favors the commitment of neural precursors towards dopaminergic, motor, enteric and adrenal neurons; in addition, it enhances the axonal growth of some of these neurons. GDNF also induces the acquisition of a dopaminergic phenotype by increasing the expression of Tyrosine Hydroxylase (TH, Nurr1 and other proteins that confer this identity and promote further dendritic and electrical maturation. In motor neurons (MNs, GDNF not only promotes proliferation and maturation but also participates in regenerating damaged axons and modulates the neuromuscular junction (NMJ at both presynaptic and postsynaptic levels. Moreover, GDNF modulates the rate of neuroblastoma (NB and glioblastoma cancer cell proliferation. Additionally, the presence or absence of GDNF has been correlated with conditions such as depression, pain, muscular soreness, etc. Although, the precise role of GDNF is unknown, it extends beyond a survival effect. The understanding of the complete range of properties of this trophic molecule will allow us to investigate its broad mechanisms of action to accelerate and/or improve therapies for the aforementioned pathological conditions.

  17. Exercise-Induced Fitness Changes Correlate with Changes in Neural Specificity in Older Adults

    Science.gov (United States)

    Kleemeyer, Maike M.; Polk, Thad A.; Schaefer, Sabine; Bodammer, Nils C.; Brechtel, Lars; Lindenberger, Ulman

    2017-01-01

    Neural specificity refers to the degree to which neural representations of different stimuli can be distinguished. Evidence suggests that neural specificity, operationally defined as stimulus-related differences in functional magnetic resonance imaging (fMRI) activation patterns, declines with advancing adult age, and that individual differences in neural specificity are associated with individual differences in fluid intelligence. A growing body of literature also suggests that regular physical activity may help preserve cognitive abilities in old age. Based on this literature, we hypothesized that exercise-induced improvements in fitness would be associated with greater neural specificity among older adults. A total of 52 adults aged 59–74 years were randomly assigned to one of two aerobic-fitness training regimens, which differed in intensity. Participants in both groups trained three times a week on stationary bicycles. In the low-intensity (LI) group, the resistance was kept constant at a low level (10 Watts). In the high-intensity (HI) group, the resistance depended on participants’ heart rate and therefore typically increased with increasing fitness. Before and after the 6-month training phase, participants took part in a functional MRI experiment in which they viewed pictures of faces and buildings. We used multivariate pattern analysis (MVPA) to estimate the distinctiveness of neural activation patterns in ventral visual cortex (VVC) evoked by face or building stimuli. Fitness was also assessed before and after training. In line with our hypothesis, training-induced changes in fitness were positively associated with changes in neural specificity. We conclude that physical activity may protect against age-related declines in neural specificity. PMID:28360850

  18. Effects of hypoxia-inducible factor 1 on ischemic cerebrovascular disease

    Institute of Scientific and Technical Information of China (English)

    Yongjie Luo; Xiaoping Wang; Hongbin Sun

    2008-01-01

    Hypoxia-inducible factor I, a nuclear transcription factor, is induced by hypoxia. Hypoxia-inducible factor I, a heterodimeric DNA-binding protein, is composed of hypoxia-inducible factor 1α and hypoxia-inducible factor 1 β subunits, which are family members of the basic helix-loop-helix-PER, ARNT, SIM (PAS) protein. O2 concentration regulates hypoxia-inducible factor 1 activity via this subunit. Hypoxia-inducible factor 1α plays a major role in response to hypoxia and transcriptional activation, as well as in the target gene specificity of the DNA enhancer. Hypoxia-inducible factor 1β cannot be induced by hypoxia. This effect may be due to hypoxia-inducible factor 1 stability and activated conformation due to dimerization. Previous studies have shown that hypoxia-inducible factor 1 mRNA expression increases in the penumbra following ischemia/hypoxia. Hypoxia-inducible factor 1 plays an important role in brain tissue injury alter ischemia by affecting a series of target genes, elevating tolerance to hypoxia, and ensuring survival of neural cells. This article summarizes the structure, function, expression, regulatory mechanisms, biological effects, and significance of hypoxia-inducible factor 1 in patients with ischemic cerebrovascular disease. As a transcriptional activator, hypoxia- inducible factor 1 plays a key role in hypoxic responses by stabilizing the internal environment. It also has been shown to regulate the expression of several genes. The regulatory effects of hypoxia-inducible factor 1 in patients with ischemic cerebrovascular disease have been described. The present review re-examined the concept of brain protection at the level of gene regulation.

  19. An improved protocol that induces human embryonic stem cells to differentiate into neural cells in vitro.

    Science.gov (United States)

    Zhou, Jun-Mei; Chu, Jian-Xin; Chen, Xue-Jin

    2008-01-01

    Human embryonic stem (ES) cells have the capacity for self-renewal and are able to differentiate into any cell type. However, obtaining high-efficient neural differentiation from human ES cells remains a challenge. This study describes an improved 4-stage protocol to induce a human ES cell line derived from a Chinese population to differentiate into neural cells. At the first stage, embryonic bodies (EBs) were formed in a chemically-defined neural inducing medium rather than in traditional serum or serum-replacement medium. At the second stage, rosette-like structures were formed. At the third stage, the rosette-like structures were manually selected rather than enzymatically digested to form floating neurospheres. At the fourth stage, the neurospheres were further differentiated into neurons. The results show that, at the second stage, the rate of the formation of rosette-like structures from EBs induced by noggin was 88+/-6.32%, higher than that of retinoic acid 55+/-5.27%. Immunocytochemistry staining was used to confirm the neural identity of the cells. These results show a major improvement in obtaining efficient neural differentiation of human ES cells.

  20. Injury-induced neurogenesis: consideration of resident microglia as supportive of neural progenitor cells.

    Science.gov (United States)

    McPherson, Christopher A; Kraft, Andrew D; Harry, G Jean

    2011-02-01

    The induction of neurogenesis in the adult subgranular zone (SGZ) by injury is often accompanied by changes in the extracellular environment that can have significant impacts on neural progenitor cells (NPCs). We examined the induction of neurogenesis in the SGZ at 72 h following an injection of the hippocampal toxicant, trimethyltin (TMT; 2 mg/kg, ip) inducing apoptosis in dentate granule neurons. BrdU+ incorporation during the active period of neuronal death indicated NPC proliferation and migration of newly generated cells into the granule cell layer (GCL). BrdU+ cells were transiently in contact with process bearing microglia within the inner SGZ layer. Contact with GFAP+ astrocyte processes occurred once cells were within the GCL. A small percentage of the BrdU+ cells within the SGZ region showed immunoreactivity for tumor necrosis factor (TNF) p75 receptor (TNFp75R). In mice deficient for TNFp75R, TMT injection produced an equivalent level of dentate granule cell death however; BrdU+ cells were localized at the SGZ as compared to the presence of cells within the GCL in the WT mice dosed with TMT. These data suggest that cells generated by NPCs in the SGZ induced with a focal lesion to the dentate granule neurons of adolescent mice maintain the capacity to utilize the neuroinflammation and microglia responses within their environment for migration into the GCL.

  1. Therapeutic Potential of Induced Neural Stem Cells for Parkinson’s Disease

    Science.gov (United States)

    Choi, Dong-Hee; Kim, Ji-Hye; Kim, Sung Min; Kang, Kyuree; Han, Dong Wook; Lee, Jongmin

    2017-01-01

    Parkinson’s disease (PD) is a chronic, neurodegenerative disorder that results from the loss of cells in the substantia nigra (SN) which is located in the midbrain. However, no cure is available for PD. Recently, fibroblasts have been directly converted into induced neural stem cells (iNSCs) via the forced expression of specific transcription factors. Therapeutic potential of iNSC in PD has not been investigated yet. Here, we show that iNSCs directly converted from mouse fibroblasts enhanced functional recovery in an animal model of PD. The rotational behavior test was performed to assess recovery. Our results indicate that iNSC transplantation into the striatum of 6-hydroxydopamine (6-OHDA)-injected mice can significantly reduce apomorphine-induced rotational asymmetry. The engrafted iNSCs were able to survive in the striatum and migrated around the medial forebrain bundle and the SN pars compacta. Moreover, iNSCs differentiated into all neuronal lineages. In particular, the transplanted iNSCs that committed to the glial lineage were significantly increased in the striatum of 6-OHDA-injected mice. Engrafted iNSCs differentiated to dopaminergic (DA) neurons and migrated into the SN in the 6-OHDA lesion mice. Therefore, iNSC transplantation serves as a valuable tool to enhance the functional recovery in PD. PMID:28117752

  2. Effects of Nerve Growth Factor and Basic Fibroblast Growth Factor Promote Human Dental Pulp Stem Cells to Neural Differentiation.

    Science.gov (United States)

    Zhang, Jinlong; Lian, Min; Cao, Peipei; Bao, Guofeng; Xu, Guanhua; Sun, Yuyu; Wang, Lingling; Chen, Jiajia; Wang, Yi; Feng, Guijuan; Cui, Zhiming

    2017-04-01

    Dental pulp stem cells (DPSCs) were the most widely used seed cells in the field of neural regeneration and bone tissue engineering, due to their easily isolation, lack of ethical controversy, low immunogenicity and low rates of transplantation rejection. The purpose of this study was to investigate the role of basic fibroblast growth factor (bFGF) and nerve growth factor (NGF) on neural differentiation of DPSCs in vitro. DPSCs were cultured in neural differentiation medium containing NGF and bFGF alone or combination for 7 days. Then neural genes and protein markers were analyzed using western blot and RT-PCR. Our study revealed that bFGF and NGF increased neural differentiation of DPSCs synergistically, compared with bFGF and NGF alone. The levels of Nestin, MAP-2, βIII-tubulin and GFAP were the most highest in the DPSCs + bFGF + NGF group. Our results suggested that bFGF and NGF signifiantly up-regulated the levels of Sirt1. After treatment with Sirt1 inhibitor, western blot, RT-PCR and immunofluorescence staining showed that neural genes and protein markers had markedly decreased. Additionally, the ERK and AKT signaling pathway played a key role in the neural differentiation of DPSCs stimulated with bFGF + NGF. These results suggested that manipulation of the ERK and AKT signaling pathway may be associated with the differentiation of bFGF and NGF treated DPSCs. Our date provided theoretical basis for DPSCs to treat neurological diseases and repair neuronal damage.

  3. Neural induced embryoid bodies present high levels of metals detected by x-ray microfluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Stelling, Mariana P.; Cardoso, Simone C.; Paulsen, Bruna S.; Rehen, Stevens K. [Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas, 373 (Brazil); Instituto de Fisica, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos, 14, 21941 Rio de Janeiro (Brazil); Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas, 373 (Brazil)

    2012-05-17

    Molecular mechanisms driving neural differentiation in human embryonic stem cells are not completely elucidated, specially, the role of atomic elements within this process. In this work, we described the distribution of trace elements in those stem cells growing as embryoid bodies by using synchrotron radiation X-ray microfluorescence (SR-XRF). Naive and neural induced embryoid bodies derived from embryonic stem cells were irradiated with a spatial resolution of 20 {mu}m to make elemental maps and qualitative chemical analyses. We consistently detected metallic elements content raise on neural induced embryoid bodies, mimicking characteristic brain development. The use of SR-XRF reveals that human embryoid bodies exhibit self-organization at the atomic level, which is enhanced during neurogenesis triggered in vitro.

  4. Neural induced embryoid bodies present high levels of metals detected by x-ray microfluorescence

    Science.gov (United States)

    Stelling, Mariana P.; Cardoso, Simone C.; Paulsen, Bruna S.; Rehen, Stevens K.

    2012-05-01

    Molecular mechanisms driving neural differentiation in human embryonic stem cells are not completely elucidated, specially, the role of atomic elements within this process. In this work, we described the distribution of trace elements in those stem cells growing as embryoid bodies by using synchrotron radiation X-ray microfluorescence (SR-XRF). Naive and neural induced embryoid bodies derived from embryonic stem cells were irradiated with a spatial resolution of 20 μm to make elemental maps and qualitative chemical analyses. We consistently detected metallic elements content raise on neural induced embryoid bodies, mimicking characteristic brain development. The use of SR-XRF reveals that human embryoid bodies exhibit self-organization at the atomic level, which is enhanced during neurogenesis triggered in vitro.

  5. Light-induced Notch activity controls neurogenic and gliogenic potential of neural progenitors.

    Science.gov (United States)

    Kim, Kyung-Tai; Song, Mi-Ryoung

    2016-10-28

    Oscillations in Notch signaling are essential for reserving neural progenitors for cellular diversity in developing brains. Thus, steady and prolonged overactivation of Notch signaling is not suitable for generating neurons. To acquire greater temporal control of Notch activity and mimic endogenous oscillating signals, here we adopted a light-inducible transgene system to induce active form of Notch NICD in neural progenitors. Alternating Notch activity saved more progenitors that are prone to produce neurons creating larger number of mixed clones with neurons and progenitors in vitro, compared to groups with no light or continuous light stimulus. Furthermore, more upper layer neurons and astrocytes arose upon intermittent Notch activity, indicating that dynamic Notch activity maintains neural progeny and fine-tune neuron-glia diversity.

  6. The meninges contribute to the conditioned taste avoidance induced by neural cooling in male rats.

    Science.gov (United States)

    Wang, Yuan; Chambers, Kathleen C

    2002-08-21

    After consumption of a novel sucrose solution, temporary cooling of neural areas that mediate conditioned taste avoidance can itself induce conditioned avoidance to the sucrose. It has been suggested that this effect is either a result of inactivation of neurons in these areas or of cooling the meninges. In a series of studies, we demonstrated that cooling the outer layer of the meninges, the dura mater, does not contribute to the conditioned taste avoidance induced by cooling any of these areas. The present experiments were designed to determine whether the inner layers of the meninges are involved. If they are involved, then one would expect that cooling locations in the brain that do not mediate conditioned taste avoidance, such as the caudate putamen (CP), would induce conditioned taste avoidance as long as the meninges were cooled as well. One also would expect that cooling neural tissue without cooling the meninges would reduce the strength of the conditioned taste avoidance. Experiment 1 established that the temperature of the neural tissue and meninges around the cold probes implanted in the CP were cooled to temperatures that have been shown to block synaptic transmission. Experiment 2 demonstrated that cooling the caudate putamen and overlying cortex and meninges induced conditioned taste avoidance. In experiment 3, a circle of meninges was cut away so that the caudate putamen and overlying cortex could be cooled without cooling the meninges. The strength of the conditioned taste avoidance was substantially reduced, but it was not entirely eliminated. These data support the hypothesis that cooling the meninges contributes to the conditioned taste avoidance induced by neural cooling. They also allow the possibility that neural inactivation produces physiological changes that can induce conditioned taste avoidance.

  7. Neural stem cells express melatonin receptors and neurotrophic factors: colocalization of the MT1 receptor with neuronal and glial markers

    Directory of Open Access Journals (Sweden)

    McMillan Catherine R

    2004-10-01

    a heterogeneous population of NSCs including both neural and glial progenitors, as observed under the cell culture conditions used in this study. These NSCs have an intrinsic ability to express neurotrophic factors, with an apparent suppression of GDNF expression after several days in culture. The detection of melatonin receptors in neural stem/progenitor cells suggests involvement of this pleiotropic hormone in mammalian neurodevelopment. Moreover, the ability of melatonin to induce GDNF expression in C17.2 cells supports a functional role for the MT1 receptor expressed in these NSCs. In view of the potency of GDNF in promoting the survival of dopaminergic neurons, these novel findings have implications for the utilization of melatonin in neuroprotective strategies, especially in Parkinson's disease.

  8. Ischemia-Induced Neural Stem/Progenitor Cells in the Pia Mater Following Cortical Infarction

    NARCIS (Netherlands)

    Nakagomi, Takayuki; Molnar, Zoltan; Nakano-Doi, Akiko; Taguchi, Akihiko; Saino, Orie; Kubo, Shuji; Clausen, Martijn; Yoshikawa, Hiroo; Nakagomi, Nami; Matsuyama, Tomohiro

    2011-01-01

    Increasing evidence shows that neural stem/ progenitor cells (NSPCs) can be activated in the nonconventional neurogenic zones such as the cortex following ischemic stroke. However, the precise origin, identity, and subtypes of the ischemia-induced NSPCs (iNSPCs), which can contribute to cortical

  9. Cysteine: A Novel Neural Inducer for Rat Bone Marrow Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Malek Soleimani Mehranjani

    2014-06-01

    Full Text Available Objective: Mesenchymal stem cells (MSCs can differentiate into various cell types. Since cysteine has structural similarities to neuronal inducers β-mercaptoethanol and glutathione, we examined its effect on neural induction of rat bone marrow MSCs. Materials and Methods: In this experimental study, cells were treated in a medium containing 1mM cysteine for 24 hours prior to treatment with neuron inducing medium containing 10 mM cysteine for 1, 2 and 3 hours. Cell viability and morphology were assessed by 3-(4,5-dimethylthiazol-2-Yl-2,5-diphenyltetrazolium bromide (MTT assay and, Hoechst, propidium iodide and acridine orange staining respectively. Expression of nestin and β-Tubulin III genes, as neural cell-specific markers, was studied reverse transcription polymerase chain reaction (RT-PCR. The data was statistically analyzed using One-Way ANOVA and Tukey’s test and p<0.05 was considered significant. Results: After 3 hours of treatment, neuron like morphology with a considerable expression of nestin and β-Tubulin III genes was apparent. The mean cell viability was not significantly different at 1, 2 and 3 hours following induction, compared with the control cells. Conclusion: Cysteine can induce neural features in rat bone marrow MSCs without reducing cell viability. Therefore, it can be considered as a safer alternative to toxic neural inducer agents such as β-mercaptoethanol.

  10. Ischemia-Induced Neural Stem/Progenitor Cells in the Pia Mater Following Cortical Infarction

    NARCIS (Netherlands)

    Nakagomi, Takayuki; Molnar, Zoltan; Nakano-Doi, Akiko; Taguchi, Akihiko; Saino, Orie; Kubo, Shuji; Clausen, Martijn; Yoshikawa, Hiroo; Nakagomi, Nami; Matsuyama, Tomohiro

    2011-01-01

    Increasing evidence shows that neural stem/ progenitor cells (NSPCs) can be activated in the nonconventional neurogenic zones such as the cortex following ischemic stroke. However, the precise origin, identity, and subtypes of the ischemia-induced NSPCs (iNSPCs), which can contribute to cortical neu

  11. Comparison of different protocols for neural differentiation of human induced pluripotent stem cells.

    Science.gov (United States)

    Salimi, Ali; Nadri, Samad; Ghollasi, Marzieh; Khajeh, Khosro; Soleimani, Masoud

    2014-03-01

    Although embryonic stem cells (ESCs) have enormous potentials due to their pluripotency, their therapeutic use is limited by ethical, biological and safety issues. Compared to ESCs, induced pluripotent stem cells (iPSCs) can be obtained from mouse or human fibroblasts by reprogramming. Numerous studies have established many protocols for differentiation of human iPSCs (hiPSCs) into neural lineages. However, the low differentiation efficiency of such protocols motivates researchers to design new protocols for high yield differentiation. Herein, we compared neural differentiation potential of three induction media for conversion of hiPSCs into neural lineages. In this study, hiPSCs-derived embryoid bodies were plated on laminin coated dishes and were treated with three induction media including (1) bFGF, EGF (2) RA and (3) forskolin, IBMX. Immunofluorescence staining and quantitative real-time PCR (qPCR) analysis were used to detect the expression of neural genes and proteins. qPCR analysis showed that the expression of neural genes in differentiated hiPSCs in forskolin, IBMX supplemented media was significantly higher than undifferentiated cells and those in induction media containing bFGF, EGF or RA. In conclusion, our results indicated a successful establishment protocol with high efficiency for differentiation of hiPSCs into neural lineages.

  12. Human induced pluripotent stem cell-derived models to investigate human cytomegalovirus infection in neural cells.

    Directory of Open Access Journals (Sweden)

    Leonardo D'Aiuto

    Full Text Available Human cytomegalovirus (HCMV infection is one of the leading prenatal causes of congenital mental retardation and deformities world-wide. Access to cultured human neuronal lineages, necessary to understand the species specific pathogenic effects of HCMV, has been limited by difficulties in sustaining primary human neuronal cultures. Human induced pluripotent stem (iPS cells now provide an opportunity for such research. We derived iPS cells from human adult fibroblasts and induced neural lineages to investigate their susceptibility to infection with HCMV strain Ad169. Analysis of iPS cells, iPS-derived neural stem cells (NSCs, neural progenitor cells (NPCs and neurons suggests that (i iPS cells are not permissive to HCMV infection, i.e., they do not permit a full viral replication cycle; (ii Neural stem cells have impaired differentiation when infected by HCMV; (iii NPCs are fully permissive for HCMV infection; altered expression of genes related to neural metabolism or neuronal differentiation is also observed; (iv most iPS-derived neurons are not permissive to HCMV infection; and (v infected neurons have impaired calcium influx in response to glutamate.

  13. Induced Pluripotent Stem Cell-Derived Neural Cells Survive and Mature in the Nonhuman Primate Brain

    Directory of Open Access Journals (Sweden)

    Marina E. Emborg

    2013-03-01

    Full Text Available The generation of induced pluripotent stem cells (iPSCs opens up the possibility for personalized cell therapy. Here, we show that transplanted autologous rhesus monkey iPSC-derived neural progenitors survive for up to 6 months and differentiate into neurons, astrocytes, and myelinating oligodendrocytes in the brains of MPTP-induced hemiparkinsonian rhesus monkeys with a minimal presence of inflammatory cells and reactive glia. This finding represents a significant step toward personalized regenerative therapies.

  14. A neural hypothesis for stress-induced headache.

    Science.gov (United States)

    Cathcart, Stuart

    2009-12-01

    The mechanisms by which stress contributes to CTH are not clearly understood. The commonly accepted notion of muscle hyper-reactivity to stress in CTH sufferers is not supported in the research data. We propose a neural model whereby stress acts supra-spinally to aggravate already increased pain sensitivity in CTH sufferers. Indirect support for the model comes from emerging research elucidating complex supra-spinal networks through which psychological stress may contribute to and even cause pain. Similarly, emerging research demonstrates supra-spinal pain processing abnormalities in CTH sufferers. While research with CTH sufferers offering direct support for the model is lacking at present, initial work by our group is consistent with the models predictions, particularly, that stress aggravates already increased pain sensitivity in CTH sufferers.

  15. The neural cell adhesion molecule binds to fibroblast growth factor receptor 2

    DEFF Research Database (Denmark)

    Christensen, Claus; Lauridsen, Jes B; Berezin, Vladimir;

    2006-01-01

    The neural cell adhesion molecule (NCAM) can bind to and activate fibroblast growth factor receptor 1 (FGFR1). However, there are four major FGFR isoforms (FGFR1-FGFR4), and it is not known whether NCAM also interacts directly with the other three FGFR isoforms. In this study, we show by surface...

  16. N-Docosahexaenoylethanolamine ameliorates ethanol-induced impairment of neural stem cell neurogenic differentiation.

    Science.gov (United States)

    Rashid, Mohammad Abdur; Kim, Hee-Yong

    2016-03-01

    Previous studies demonstrated that prenatal exposure to ethanol interferes with embryonic and fetal development, and causes abnormal neurodevelopment. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid highly enriched in the brain, was shown to be essential for proper brain development and function. Recently, we found that N-docosahexenoyethanolamine (synaptamide), an endogenous metabolite of DHA, is a potent PKA-dependent neurogenic factor for neural stem cell (NSC) differentiation. In this study, we demonstrate that ethanol at pharmacologically relevant concentrations downregulates cAMP signaling in NSC and impairs neurogenic differentiation. In contrast, synaptamide reverses ethanol-impaired NSC neurogenic differentiation through counter-acting on the cAMP production system. NSC exposure to ethanol (25-50 mM) for 4 days dose-dependently decreased the number of Tuj-1 positive neurons and PKA/CREB phosphorylation with a concomitant reduction of cellular cAMP. Ethanol-induced cAMP reduction was accompanied by the inhibition of G-protein activation and expression of adenylyl cyclase (AC) 7 and AC8, as well as PDE4 upregulation. In contrast to ethanol, synaptamide increased cAMP production, GTPγS binding, and expression of AC7 and AC8 isoforms in a cAMP-dependent manner, offsetting the ethanol-induced impairment in neurogenic differentiation. These results indicate that synaptamide can reduce ethanol-induced impairment of neuronal differentiation by counter-affecting shared targets in G-protein coupled receptor (GPCR)/cAMP signaling. The synaptamide-mediated mechanism observed in this study may offer a possible avenue for ameliorating the adverse impact of fetal alcohol exposure on neurodevelopment.

  17. dNTP deficiency induced by HU via inhibiting ribonucleotide reductase affects neural tube development.

    Science.gov (United States)

    Guan, Zhen; Wang, Xiuwei; Dong, Yanting; Xu, Lin; Zhu, Zhiqiang; Wang, Jianhua; Zhang, Ting; Niu, Bo

    2015-02-03

    Exposure to environmental toxic chemicals in utero during the neural tube development period can cause developmental disorders. To evaluate the disruption of neural tube development programming, the murine neural tube defects (NTDs) model was induced by interrupting folate metabolism using methotrexate in our previous study. The present study aimed to examine the effects of dNTP deficiency induced by hydroxyurea (HU), a specific ribonucleotide reductase (RNR) inhibitor, during murine neural tube development. Pregnant C57BL/6J mice were intraperitoneally injected with various doses of HU on gestation day (GD) 7.5, and the embryos were checked on GD 11.5. RNR activity and deoxynucleoside triphosphate (dNTP) levels were measured in the optimal dose. Additionally, DNA damage was examined by comet analysis and terminal deoxynucleotidyl transferase mediated dUTP nick end-labeling (TUNEL) assay. Cellular behaviors in NTDs embryos were evaluated with phosphorylation of histone H3 (PH-3) and caspase-3 using immunohistochemistry and western blot analysis. The results showed that NTDs were observed mostly with HU treatment at an optimal dose of 225 mg/kg b/w. RNR activity was inhibited and dNTP levels were decreased in HU-treated embryos with NTDs. Additionally, increased DNA damage, decreased proliferation, and increased caspase-3 were significant in NTDs embryos compared to the controls. Results indicated that HU induced murine NTDs model by disturbing dNTP metabolism and further led to the abnormal cell balance between proliferation and apoptosis.

  18. Exchange rate prediction with multilayer perceptron neural network using gold price as external factor

    Directory of Open Access Journals (Sweden)

    Mohammad Fathian

    2012-04-01

    Full Text Available In this paper, the problem of predicting the exchange rate time series in the foreign exchange rate market is going to be solved using a time-delayed multilayer perceptron neural network with gold price as external factor. The input for the learning phase of the artificial neural network are the exchange rate data of the last five days plus the gold price in two different currencies of the exchange rate as the external factor for helping the artificial neural network improving its forecast accuracy. The five-day delay has been chosen because of the weekly cyclic behavior of the exchange rate time series with the consideration of two holidays in a week. The result of forecasts are then compared with using the multilayer peceptron neural network without gold price external factor by two most important evaluation techniques in the literature of exchange rate prediction. For the experimental analysis phase, the data of three important exchange rates of EUR/USD, GBP/USD, and USD/JPY are used.

  19. Suppressed expression of mitogen-activated protein kinases in hyperthermia induced defective neural tube.

    Science.gov (United States)

    Zhang, Tianliang; Leng, Zhaoting; Liu, Wenjing; Wang, Xia; Yan, Xue; Yu, Li

    2015-05-06

    Neural tube defects (NTDs) are common congenital malformations. Mitogen-activated protein kinases (MAPKs) pathway is involved in many physiological processes. HMGB1 has been showed closely associated with neurulation and NTDs induced by hyperthermia and could activate MAPKs pathway. Since hyperthermia caused increased activation of MAPKs in many systems, the present study aims to investigate whether HMGB1 contributes to hyperthermia induced NTDs through MAPKs pathway. The mRNA levels of MAPKs and HMGB1 between embryonic day 8.5 and 10 (E8.5-10) in hyperthermia induced defective neural tube were detected by real-time quantitative polymerase chain reaction (qPCR). By immunofluorescence and western blotting, the expressions of HMGB1 and phosphorylated MAPKs (ERK1/2, JNK and p38) in neural tubes after hyperthermia were studied. The mRNA levels of MAPKs and HMGB1, as well as the expressions of HMGB1 along with phosphorylated JNK, p38 and ERK, were downregulated in NTDs groups induced by hyperthermia compared with control. The findings suggested that HMGB1 may contribute to hyperthermia induced NTDs formation through decreased cell proliferation due to inhibited phosphorylated ERK1/2 MAPK.

  20. Coupling Strength and System Size Induce Firing Activity of Globally Coupled Neural Network

    Institute of Scientific and Technical Information of China (English)

    WEI Du-Qu; LUO Xiao-Shu; ZOU Yan-Li

    2008-01-01

    We investigate how firing activity of globally coupled neural network depends on the coupling strength C and system size N.Network elements are described by space-clamped FitzHugh-Nagumo (SCFHN) neurons with the values of parameters at which no firing activity occurs.It is found that for a given appropriate coupling strength,there is an intermediate range of system size where the firing activity of globally coupled SCFHN neural network is induced and enhanced.On the other hand,for a given intermediate system size level,there ex/sts an optimal value of coupling strength such that the intensity of firing activity reaches its maximum.These phenomena imply that the coupling strength and system size play a vital role in firing activity of neural network.

  1. Transdifferentiation-Induced Neural Stem Cells Promote Recovery of Middle Cerebral Artery Stroke Rats.

    Science.gov (United States)

    Yao, Hui; Gao, Mou; Ma, Jianhua; Zhang, Maoying; Li, Shaowu; Wu, Bingshan; Nie, Xiaohu; Jiao, Jiao; Zhao, Hao; Wang, Shanshan; Yang, Yuanyuan; Zhang, Yesen; Sun, Yilin; Wicha, Max S; Chang, Alfred E; Gao, Shaorong; Li, Qiao; Xu, Ruxiang

    2015-01-01

    Induced neural stem cells (iNSCs) can be directly transdifferentiated from somatic cells. One potential clinical application of the iNSCs is for nerve regeneration. However, it is unknown whether iNSCs function in disease models. We produced transdifferentiated iNSCs by conditional overexpressing Oct4, Sox2, Klf4, c-Mycin mouse embryonic fibroblasts. They expanded readily in vitro and expressed NSC mRNA profile and protein markers. These iNSCs differentiated into mature astrocytes, neurons and oligodendrocytes in vitro. Importantly, they reduced lesion size, promoted the recovery of motor and sensory function as well as metabolism status in middle cerebral artery stroke rats. These iNSCs secreted nerve growth factors, which was associated with observed protection of neurons from apoptosis. Furthermore, iNSCs migrated to and passed through the lesion in the cerebral cortex, where Tuj1+ neurons were detected. These findings have revealed the function of transdifferentiated iNSCs in vivo, and thus provide experimental evidence to support the development of personalized regenerative therapy for CNS diseases by using genetically engineered autologous somatic cells.

  2. Transdifferentiation-Induced Neural Stem Cells Promote Recovery of Middle Cerebral Artery Stroke Rats.

    Directory of Open Access Journals (Sweden)

    Hui Yao

    Full Text Available Induced neural stem cells (iNSCs can be directly transdifferentiated from somatic cells. One potential clinical application of the iNSCs is for nerve regeneration. However, it is unknown whether iNSCs function in disease models. We produced transdifferentiated iNSCs by conditional overexpressing Oct4, Sox2, Klf4, c-Mycin mouse embryonic fibroblasts. They expanded readily in vitro and expressed NSC mRNA profile and protein markers. These iNSCs differentiated into mature astrocytes, neurons and oligodendrocytes in vitro. Importantly, they reduced lesion size, promoted the recovery of motor and sensory function as well as metabolism status in middle cerebral artery stroke rats. These iNSCs secreted nerve growth factors, which was associated with observed protection of neurons from apoptosis. Furthermore, iNSCs migrated to and passed through the lesion in the cerebral cortex, where Tuj1+ neurons were detected. These findings have revealed the function of transdifferentiated iNSCs in vivo, and thus provide experimental evidence to support the development of personalized regenerative therapy for CNS diseases by using genetically engineered autologous somatic cells.

  3. Induced pluripotent stem cell-derived neural stem cell therapies for spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Corinne A Lee-Kubli; Paul Lu

    2015-01-01

    The greatest challenge to successful treatment of spinal cord injury is the limited regenerative capacity of the central nervous system and its inability to replace lost neurons and severed axons following injury. Neural stem cell grafts derived from fetal central nervous system tissue or embryonic stem cells have shown therapeutic promise by differentiation into neurons and glia that have the potential to form functional neuronal relays across injured spinal cord segments. However, implementation of fetal-derived or embryonic stem cell-derived neural stem cell ther-apies for patients with spinal cord injury raises ethical concerns. Induced pluripotent stem cells can be generated from adult somatic cells and differentiated into neural stem cells suitable for therapeutic use, thereby providing an ethical source of implantable cells that can be made in an autologous fashion to avoid problems of immune rejection. This review discusses the therapeutic potential of human induced pluripotent stem cell-derived neural stem cell transplantation for treatment of spinal cord injury, as well as addressing potential mechanisms, future perspectives and challenges.

  4. Induction of Excess Centrosomes in Neural Progenitor Cells during the Development of Radiation-Induced Microcephaly.

    Directory of Open Access Journals (Sweden)

    Mikio Shimada

    Full Text Available The embryonic brain is one of the tissues most vulnerable to ionizing radiation. In this study, we showed that ionizing radiation induces apoptosis in the neural progenitors of the mouse cerebral cortex, and that the surviving progenitor cells subsequently develop a considerable amount of supernumerary centrosomes. When mouse embryos at Day 13.5 were exposed to γ-rays, brains sizes were reduced markedly in a dose-dependent manner, and these size reductions persisted until birth. Immunostaining with caspase-3 antibodies showed that apoptosis occurred in 35% and 40% of neural progenitor cells at 4 h after exposure to 1 and 2 Gy, respectively, and this was accompanied by a disruption of the apical layer in which mitotic spindles were positioned in unirradiated mice. At 24 h after 1 Gy irradiation, the apoptotic cells were completely eliminated and proliferation was restored to a level similar to that of unirradiated cells, but numerous spindles were localized outside the apical layer. Similarly, abnormal cytokinesis, which included multipolar division and centrosome clustering, was observed in 19% and 24% of the surviving neural progenitor cells at 48 h after irradiation with 1 and 2 Gy, respectively. Because these cytokinesis aberrations derived from excess centrosomes result in growth delay and mitotic catastrophe-mediated cell elimination, our findings suggest that, in addition to apoptosis at an early stage of radiation exposure, radiation-induced centrosome overduplication could contribute to the depletion of neural progenitors and thereby lead to microcephaly.

  5. Functional and topographic concordance of right atrial neural structures inducing sinus tachycardia.

    Science.gov (United States)

    Eickholt, Christian; Mischke, Karl; Schimpf, Thomas; Knackstedt, Christian; Scherer, Kira; Pauza, Danius; Marx, Nikolaus; Shin, Dong-In; Kelm, Malte; Meyer, Christian

    2013-01-01

    Cardiorespiratory autonomic control is in tight interaction with an intracardiac neural network modulating sinus node function. To gain novel mechanistical insights and to investigate possible novel targets concerning the treatment of inadequate sinus tachycardia, we aimed to characterize functionally and topographically the right atrial neural network modulating sinus node function. In 16 sheep 3-dimensional electro-anatomical mapping of the right atrium was performed. In five animals additionally magnetically steered remote navigation was used. Selective stimulation of nerve fibers was conducted by applying high frequency (200 Hz) electrical impulses within the atrial refractory period. Histological analysis of whole heart preparations by acetylcholinesterase staining was performed and compared to the acquired neuroanatomical mapping.We found that neural stimulation in the cranial part of the right atrium, within a perimeter around the sinus node area, elicited predominantly shortening of the sinus cycle length of -20.3 ± 10.1 % (n = 80, P < 0.05). Along the course of the crista terminalis atrial premature beats (n = 117) and atrial fibrillation (n = 123) could be induced. Catheter stability was excellent during remote catheter navigation. Histological work-up (n = 4) was in accord with the distribution of neurostimulation sites. Ganglions were mainly innervated by the dorsal right-atrial subplexus, with substantial additional input from the ventral right atrial subplexus. In conclusion, our findings suggest a functional and topographic concordance of right atrial neural structures inducing sinus tachycardia. This might open up new avenues in the treatment of heart rate related disorders.

  6. Recognition of edible oil by using BP neural network and laser induced fluorescence spectrum

    Science.gov (United States)

    Mu, Tao-tao; Chen, Si-ying; Zhang, Yin-chao; Guo, Pan; Chen, He; Zhang, Hong-yan; Liu, Xiao-hua; Wang, Yuan; Bu, Zhi-chao

    2013-09-01

    In order to accomplish recognition of the different edible oil we set up a laser induced fluorescence spectrum system in the laboratory based on Laser induced fluorescence spectrum technology, and then collect the fluorescence spectrum of different edible oil by using that system. Based on this, we set up a fluorescence spectrum database of different cooking oil. It is clear that there are three main peak position of different edible oil from fluorescence spectrum chart. Although the peak positions of all cooking oil were almost the same, the relative intensity of different edible oils was totally different. So it could easily accomplish that oil recognition could take advantage of the difference of relative intensity. Feature invariants were extracted from the spectrum data, which were chosen from the fluorescence spectrum database randomly, before distinguishing different cooking oil. Then back propagation (BP) neural network was established and trained by the chosen data from the spectrum database. On that basis real experiment data was identified by BP neural network. It was found that the overall recognition rate could reach as high as 83.2%. Experiments showed that the laser induced fluorescence spectrum of different cooking oil was very different from each other, which could be used to accomplish the oil recognition. Laser induced fluorescence spectrum technology, combined BP neural network,was fast, high sensitivity, non-contact, and high recognition rate. It could become a new technique to accomplish the edible oil recognition and quality detection.

  7. Phase-noise-induced resonance in arrays of coupled excitable neural models.

    Science.gov (United States)

    Xiaoming Liang; Liang Zhao

    2013-08-01

    Recently, it is observed that, in a single neural model, phase noise (time-varying signal phase) arising from an external stimulating signal can induce regular spiking activities even if the signal is subthreshold. In addition, it is also uncovered that there exists an optimal phase noise intensity at which the spiking rhythm coincides with the frequency of the subthreshold signal, resulting in a phase-noise-induced resonance phenomenon. However, neurons usually do not work alone, but are connected in the form of arrays or blocks. Therefore, we study the spiking activity induced by phase noise in arrays of globally and locally coupled excitable neural models. We find that there also exists an optimal phase noise intensity for generating large neural response and such an optimal value is significantly decreased compared to an isolated single neuron case, which means the detectability in response to the subthreshold signal of neurons is sharply improved because of the coupling. In addition, we reveal two new resonance behaviors in the neuron ensemble with the presence of phase noise: there exist optimal values of both coupling strength and system size, where the coupled neurons generate regular spikes under subthreshold stimulations, which are called as coupling strength and system size resonance, respectively. Finally, the dependence of phase-noise-induced resonance on signal frequency is also examined.

  8. Comparison of S-nitrosoglutathione- and staurosporine-induced apoptosis in human neural cells.

    Science.gov (United States)

    Sodja, Caroline; Ribecco-Lutkiewicz, Maria; Haukenfrers, Julie; Merchant, Fahar; Costain, Willard J; Bani-Yaghoub, Mahmud

    2014-12-01

    S-nitrosoglutathione (GSNO) is an endogenously produced S-nitrosylating compound that controls the function of various proteins. While a number of rodent cell lines have been used to study GSNO-induced apoptosis, the mechanisms of action remain to be evaluated in human cells and in parallel with other common apoptosis-inducing agents. In this study, we compared the pro-apoptotic effects of GSNO and staurosporine (STS) on human neural progenitors (NT2, hNP1) and neuroblasts (SH-SY5Y). We show that these cells exhibit comparable levels of susceptibility to GSNO- and STS-induced apoptotic cell death, as demonstrated by condensed nuclei and CASP3 activation. Mechanistic differences in apoptotic responses were observed as differential patterns of DNA fragmentation and levels of BAX, BCL-XL, CASP8, and p-ERK in response to GSNO and STS treatment. Mitochondrial membrane potential analysis revealed that NT2 and hNP1 cells, but not SH-SY5Y cells, undergo mitochondrial hyperpolarization in response to short-term exposure to STS prior to undergoing subsequent depolarization. This is the first study to report differences in apoptotic responses to GSNO and STS in 3 complementary human neural cell lines. Furthermore, these cells represent useful tools in cell pharmacological paradigms in which susceptibility to apoptosis-inducing agents needs to be assessed at different stages of neural cell fate commitment and differentiation.

  9. RE1 silencing transcription factor/neuron-restrictive silencing factor regulates expansion of adult mouse subventricular zone-derived neural stem/progenitor cells in vitro.

    Science.gov (United States)

    Soldati, Chiara; Caramanica, Pasquale; Burney, Matthew J; Toselli, Camilla; Bithell, Angela; Augusti-Tocco, Gabriella; Stanton, Lawrence W; Biagioni, Stefano; Buckley, Noel J; Cacci, Emanuele

    2015-08-01

    Adult neural stem cell (aNSC) activity is tuned by external stimuli through the recruitment of transcription factors. This study examines the RE1 silencing transcription factor (REST) in neural stem/progenitor cells isolated from the subventricular zone of adult mouse brain and provides the first extensive characterization of REST-mediated control of the cellular and molecular properties. This study shows that REST knockdown affects the capacity of progenitor cells to generate neurospheres, reduces cell proliferation, and triggers cell differentiation despite the presence of growth factors. Genome- and transcriptome-wide analyses show that REST binding sites are significantly enriched in genes associated with synaptic transmission and nervous system development and function. Seeking candidate regulators of aNSC function, this study identifies a member of the bone morphogenetic protein (BMP) family, BMP6, the mRNA and protein of which increased after REST knockdown. The results of this study extend previous findings, demonstrating a reciprocal control of REST expression by BMPs. Administration of exogenous BMP6 inhibits aNSC proliferation and induces the expression of the astrocytic marker glial fibrillary acidic protein, highlighting its antimitogenic and prodifferentiative effects. This study suggests that BMP6 produced in a REST-regulated manner together with other signals can contribute to regulation of NSC maintenance and fate.

  10. Effect of epidermal growth factor on the migration of neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Faliang Duan; Guoping Yang; Junwu Wei; Jinglei Wu

    2006-01-01

    BACKGROUND:Recently,researches on neural stem cells(NSCs)are focus on differentiation and migration of stem cells.How to regulate and control differentiation and migration of NSCs based on human wills is still a hot topic.OBJECTIVE:To investigate the effct of epidermal growth factor (EGF) on the migration and proliferation of NSCs and analyze duration of the effect.DESIGN:Contrast study based on cells.SETFING:Department of Neurological Surgery,the First Hospital of Wuhan.MATERIALS:Healthy SD rats aged 13-14 embryonic days.EGF(Sigma Company).METHODS:The experiment was carried out in the Animal Laboratory of Experimental Center Affiliated to the First Hospital of Wuhan from October 2004 to July 2006.NSCs selected from embryonic striatum of rats with 13-14 embryonic days were cultured;7 days later,suspended neural sphere was used to make simple cell suspension and cultured once more.Then,DMEM-F12+20 μg/L EGF was added into culture medium;14 days latar.the rats were divided into experimental group and control group.Rats in the experimental group were cultured with the same medium mentioned above;however, rats in the control group were cultured with only DMEM-F12.Migration of cells was observed under microscope every day.MAIN OUTCOME MEASURES:NSCs migration in both experimental group and control group.RESULTS:Cell spheres in primary culture were NSCs.In addition,14 days later,proliferation of stem cells were observed remarkably in EGF culture.and size of cell sphere was about that of 100 cells.In exparimental group.proliferation of cell sphere was slow down on the 14th culture day,and apophysis was erupted to neighbor cell sphere.Moreover,NSCs migrated from big cell sphere to small cell sphere during 14-17 culture days.and then,cell migration was disappeared at 17 days after culture.In control group.cell migration was not observed.CONCLUSION:EGF can induce proliferation and migration of NSCs during a special time(14-17 days).However,NSCs do not immigrate over the

  11. Face-induced expectancies influence neural mechanisms of performance monitoring.

    Science.gov (United States)

    Osinsky, Roman; Seeger, Jennifer; Mussel, Patrick; Hewig, Johannes

    2016-04-01

    In many daily situations, the consequences of our actions are predicted by cues that are often social in nature. For instance, seeing the face of an evaluator (e.g., a supervisor at work) may activate certain evaluative expectancies, depending on the history of prior encounters with that particular person. We investigated how such face-induced expectancies influence neurocognitive functions of performance monitoring. We recorded an electroencephalogram while participants completed a time-estimation task, during which they received performance feedback from a strict and a lenient evaluator. During each trial, participants first saw the evaluator's face before performing the task and, finally, receiving feedback. Therefore, faces could be used as predictive cues for the upcoming evaluation. We analyzed electrocortical signatures of performance monitoring at the stages of cue processing, task performance, and feedback reception. Our results indicate that, at the cue stage, seeing the strict evaluator's face results in an anticipatory preparation of fronto-medial monitoring mechanisms, as reflected by a sustained negative-going amplitude shift (i.e., the contingent negative variation). At the performance stage, face-induced expectancies of a strict evaluation rule led to increases of early performance monitoring signals (i.e., frontal-midline theta power). At the final stage of feedback reception, violations of outcome expectancies differentially affected the feedback-related negativity and frontal-midline theta power, pointing to a functional dissociation between these signatures. Altogether, our results indicate that evaluative expectancies induced by face-cues lead to adjustments of internal performance monitoring mechanisms at various stages of task processing.

  12. Hypoxia induces microglia autophagy and neural inflammation injury in focal cerebral ischemia model.

    Science.gov (United States)

    Yang, Zhao; Zhong, Lina; Zhong, Shanchuan; Xian, Ronghua; Yuan, Bangqing

    2015-04-01

    Much evidence demonstrated that autophagy played an important role in neural inflammation response after ischemia stroke. However, the specific effect of microglia autophagy in cerebral ischemia is still unknown. In the current study, we constructed focal cerebral ischemia model by permanent middle cerebral artery occlusion (pMCAO) in mice. We detected microglia autophagy and inflammation response in vivo, and observed infarct brain areas, edema formation, and neurological deficits of mice. We found that pMCAO induced microglia autophagy and inflammatory response. The suppression of autophagy using either pharmacologic inhibitor (3-MA) not only decreased the microglia autophagy and inflammatory response, but also significantly decreased infarct size, edema formation and neurological deficits in vivo. Taken together, these results suggested that cerebral ischemia induced microglia autophagy contributed to ischemic neural inflammation and injury. In addition, our findings also provided novel therapeutic strategy for ischemic stroke. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Effects of resveratrol on hydrogen peroxide-induced oxidative stress in embryonic neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Sibel Konyalioglu; Guliz Armagan; Ayfer Yalcin; Cigdem Atalayin; Taner Dagci

    2013-01-01

    Resveratrol, a natural phenolic compound, has been shown to prevent cardiovascular diseases and cancer and exhibit neuroprotective effects. In this study, we examined the neuroprotective and antioxidant effects of resveratrol against hydrogen peroxide in embryonic neural stem cells. Hydrogen peroxide treatment alone increased catalase and glutathione peroxidase activities but did not change superoxide dismutase levels compared with hydrogen peroxide + resveratrol treatment. Nitric oxide synthase activity and concomitant nitric oxide levels increased in response to hydrogen peroxide treatment. Conversely, resveratrol treatment decreased nitric oxide synthase activity and nitric oxide levels. Resveratrol also attenuated hydrogen peroxide-induced nuclear or mitochondrial DNA damage. We propose that resveratrol may be a promising agent for protecting embryonic neural stem cells because of its potential to decrease oxidative stress by inducing higher activity of antioxidant enzymes, decreasing nitric oxide production and nitric oxide synthase activity, and alleviating both nuclear and mitochondrial DNA damage.

  14. Identification of neural cell adhesion molecule L1-derived neuritogenic ligands of the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Kulahin, Nikolaj; Li, Shizhong; Kiselyov, Vladislav

    2009-01-01

    The neural cell adhesion molecule L1 plays an important role in axon growth, neuronal survival, and synaptic plasticity. We recently demonstrated that the L1 fibronectin type III (FN3) modules interact directly with the fibroblast growth factor (FGF) receptor (FGFR). Sequence alignment of individ......The neural cell adhesion molecule L1 plays an important role in axon growth, neuronal survival, and synaptic plasticity. We recently demonstrated that the L1 fibronectin type III (FN3) modules interact directly with the fibroblast growth factor (FGF) receptor (FGFR). Sequence alignment...... of individual L1 FN3 modules with various FGFs suggested that four sequence motifs located in the third and fifth L1 FN3 modules might be involved in interactions with FGFR. The present study found that corresponding synthetic peptides, termed elcamins 1, 2, 3, and 4, bind and activate FGFR in the absence...... of FGF1. Conversely, in the presence of FGF1, elcamins inhibited receptor phosphorylation, indicating that the peptides are FGFR partial agonists. Elcamins 1, 3, and 4 dose dependently induced neurite outgrowth in cultured primary cerebellar neurons. The neuritogenic effect of elcamins was dependent...

  15. A Panel of Autoantibodies Against Neural Proteins as Peripheral Biomarker for Pesticide-Induced Neurotoxicity.

    Science.gov (United States)

    El Rahman, Heba Allah Abd; Salama, Mohamed; Gad El-Hak, Seham A; El-Harouny, Mona A; ElKafrawy, Passent; Abou-Donia, Mohamed B

    2017-09-05

    In the present study, we screened the sera of subjects chronically exposed to mixtures of pesticides (composed mainly of organophosphorus compounds (OPs) and others) and developed neurological symptoms for the presence of autoantibodies against cytoskeletal neural proteins. OPs have a well-characterized clinical profile resulting from acute cholinergic crisis. However, some of these compounds cause neuronal degeneration and demyelination known as organophosphorus compound-induced delayed neurotoxicity (OPIDN) and/or organophosphorus compound-induced chronic neurotoxicity (OPICN). Studies from our group have demonstrated the presence of autoantibodies to essential neuronal and glial proteins against cytoskeletal neural proteins in patients with chemical-induced brain injury. In this study, we screened the serum of 50 pesticide-exposed subjects and 25 non-exposed controls, using Western blot analysis against the following proteins: neurofilament triplet proteins (NFPs), tubulin, microtubule-associated tau proteins (Tau), microtubule-associated protein-2 (MAP-2), myelin basic protein (MBP), myelin-associated glycoprotein (MAG), glial fibrillary acidic protein (GFAP), calcium-calmodulin kinase II (CaMKII), glial S100-B protein, and alpha-synuclein (SNCA). Serum reactivity was measured as arbitrary chemiluminescence units. As a group, exposed subjects had significantly higher levels of autoantibody reactivity in all cases examined. The folds of increase in of autoantibodies against neural proteins of the subjects compared to healthy humans in descending order were as follows: MBP, 7.67, MAG 5.89, CaMKII 5.50, GFAP 5.1, TAU 4.96, MAP2 4.83, SNCA 4.55, NFP 4.55, S-100B 2.43, and tubulin 1.78. This study has demonstrated the presence of serum autoantibodies to central nervous system-specific proteins in a group of farmers chronically exposed to pesticides who developed neurological signs and symptoms of neural injury. These autoantibodies can be used as future diagnostic

  16. DNA methylation analysis of Homeobox genes implicates HOXB7 hypomethylation as risk factor for neural tube defects.

    Science.gov (United States)

    Rochtus, Anne; Izzi, Benedetta; Vangeel, Elise; Louwette, Sophie; Wittevrongel, Christine; Lambrechts, Diether; Moreau, Yves; Winand, Raf; Verpoorten, Carla; Jansen, Katrien; Van Geet, Chris; Freson, Kathleen

    2015-01-01

    Neural tube defects (NTDs) are common birth defects of complex etiology. Though family- and population-based studies have confirmed a genetic component, the responsible genes for NTDs are still largely unknown. Based on the hypothesis that folic acid prevents NTDs by stimulating methylation reactions, epigenetic factors, such as DNA methylation, are predicted to be involved in NTDs. Homeobox (HOX) genes play a role in spinal cord development and are tightly regulated in a spatiotemporal and collinear manner, partly by epigenetic modifications. We have quantified DNA methylation for the different HOX genes by subtracting values from a genome-wide methylation analysis using leukocyte DNA from 10 myelomeningocele (MMC) patients and 6 healthy controls. From the 1575 CpGs profiled for the 4 HOX clusters, 26 CpGs were differentially methylated (P-value 0.05) between MMC patients and controls. Seventy-seven percent of these CpGs were located in the HOXA and HOXB clusters, with the most profound difference for 3 CpGs within the HOXB7 gene body. A validation case-control study including 83 MMC patients and 30 unrelated healthy controls confirmed a significant association between MMC and HOXB7 hypomethylation (-14.4%; 95% CI: 11.9-16.9%; P-value T genotype. Significant HOXB7 hypomethylation was also present in 12 unaffected siblings, each related to a MMC patient, suggestive of an epigenetic change induced by the mother. The inclusion of a neural tube formation model using zebrafish showed that Hoxb7a overexpression but not depletion resulted in deformed body axes with dysmorphic neural tube formation. Our results implicate HOXB7 hypomethylation as risk factor for NTDs and highlight the importance for future genome-wide DNA methylation analyses without preselecting candidate pathways.

  17. Direct reprogramming of Sertoli cells into multipotent neural stem cells by defined factors

    Institute of Scientific and Technical Information of China (English)

    Chao Sheng; Ziwei Wang; Changlong Guo; Hua-Jun Wu; Zhonghua Liu; Liu Wang; Shigang He; Xiu-Jie Wang; Zhiguo Chen; Qi Zhou; Qinyuan Zheng; Jianyu Wu; Zhen Xu; Libin Wang; Wei Li; Haijiang Zhang; Xiao-YangZhao; Lei Liu

    2012-01-01

    Multipotent neural stem/progenitor cells hold great promise for cell therapy.The reprogramming of fibroblasts to induced pluripotent stem cells as well as mature neurons suggests a possibility to convert a terminally differentiated somatic cell into a muitipotent state without first establishing pluripotency.Here,we demonstrate that sertoli cells derived from mesoderm can be directly converted into a multipotent state that possesses neural stem/progenitor cell properties.The induced neural stem/progenitor cells (iNSCs) express multiple NSC-specific markers,exhibit a global gene-expression profile similar to normal NSCs,and are capable of self-renewal and differentiating into glia and electrophysiologically functional neurons,iNSC-derived neurons stain positive for tyrosine hydroxylase (TH),γ-aminobutyric acid,and choline acetyltransferase.In addition,iNSCs can survive and generate synapses following transplantation into the dentate gyrus.Generation of iNSCs may have important implications for disease modeling and regenerative medicine.

  18. Neural Tube Defect in Alive Neonates: Incidence Rate and Predisposing Factors

    Directory of Open Access Journals (Sweden)

    F Haghollahi

    2008-06-01

    Full Text Available Background: Neural Tube Defect (NTD characterized by failure of neural tube to close properly be the second most common born defect after congenital heart disease. The most prevalent forms of NTD are Anencephaly and Spinal-bifida. Many factors are involved in this anomaly. New researches suggest environmental factors like radiation, hyperthermia, Vitamin A and acid folic deficiency, anti epileptic drug like Carbamazepine, Phenobarbital, phenytoin, Folic acid antagonist like Sulfasalazine, Triametherine and systemic disease like diabet mellitus, obesity, genetic factors, the most schance 40 to 70 percentages.Methods: In this survey cross sectional study was conducted in five hospitals depend to Tehran university during three years. Study subject identified through review of admission and discharge at major hospital through regular contact with newborn nurseries and birth hospital.Results: In 38473 reported cases, 143 cases have neural tube defect. Among NTD cases, 11.9% of mothers had medical diseases in their previous history such as diabetes mellitus, epilepsy-psychiatric, and disorder-heart diseases. In this study group, 5.6% have preclampsia during pregnancy period. The most common NTD anomaly in this study was anencephaly and meningomyelocele that was different from studies in literature.Conclusion: NTD result from failure of neural tube close threats fetus health up to 28 days after conception. When is often prior to the recognition of pregnancy since many pregnancy are unplanned NTD prevention is best achieve by adequate daily folic acid intake thought of reproductive ages .educational effort to promote daily intake of folic acid supplemental by women of reproductive age and NTD risk factor should be done. Early diagnostic procedure for high risk pregnancy advised.

  19. Organogenesis relies on SoxC transcription factors for the survival of neural and mesenchymal progenitors.

    Science.gov (United States)

    Bhattaram, Pallavi; Penzo-Méndez, Alfredo; Sock, Elisabeth; Colmenares, Clemencia; Kaneko, Kotaro J; Vassilev, Alex; Depamphilis, Melvin L; Wegner, Michael; Lefebvre, Véronique

    2010-04-12

    During organogenesis, neural and mesenchymal progenitor cells give rise to many cell lineages, but their molecular requirements for self-renewal and lineage decisions are incompletely understood. In this study, we show that their survival critically relies on the redundantly acting SoxC transcription factors Sox4, Sox11 and Sox12. The more SoxC alleles that are deleted in mouse embryos, the more severe and widespread organ hypoplasia is. SoxC triple-null embryos die at midgestation unturned and tiny, with normal patterning and lineage specification, but with massively dying neural and mesenchymal progenitor cells. Specific inactivation of SoxC genes in neural and mesenchymal cells leads to selective apoptosis of these cells, suggesting SoxC cell-autonomous roles. Tead2 functionally interacts with SoxC genes in embryonic development, and is a direct target of SoxC proteins. SoxC genes therefore ensure neural and mesenchymal progenitor cell survival, and function in part by activating this transcriptional mediator of the Hippo signalling pathway.

  20. Comparative transcriptome analysis in induced neural stem cells reveals defined neural cell identities in vitro and after transplantation into the adult rodent brain.

    Science.gov (United States)

    Hallmann, Anna-Lena; Araúzo-Bravo, Marcos J; Zerfass, Christina; Senner, Volker; Ehrlich, Marc; Psathaki, Olympia E; Han, Dong Wook; Tapia, Natalia; Zaehres, Holm; Schöler, Hans R; Kuhlmann, Tanja; Hargus, Gunnar

    2016-05-01

    Reprogramming technology enables the production of neural progenitor cells (NPCs) from somatic cells by direct transdifferentiation. However, little is known on how neural programs in these induced neural stem cells (iNSCs) differ from those of alternative stem cell populations in vitro and in vivo. Here, we performed transcriptome analyses on murine iNSCs in comparison to brain-derived neural stem cells (NSCs) and pluripotent stem cell-derived NPCs, which revealed distinct global, neural, metabolic and cell cycle-associated marks in these populations. iNSCs carried a hindbrain/posterior cell identity, which could be shifted towards caudal, partially to rostral but not towards ventral fates in vitro. iNSCs survived after transplantation into the rodent brain and exhibited in vivo-characteristics, neural and metabolic programs similar to transplanted NSCs. However, iNSCs vastly retained caudal identities demonstrating cell-autonomy of regional programs in vivo. These data could have significant implications for a variety of in vitro- and in vivo-applications using iNSCs.

  1. Predicting musically induced emotions from physiological inputs: Linear and neural network models

    Directory of Open Access Journals (Sweden)

    Frank A. Russo

    2013-08-01

    Full Text Available Listening to music often leads to physiological responses. Do these physiological responses contain sufficient information to infer emotion induced in the listener? The current study explores this question by attempting to predict judgments of 'felt' emotion from physiological responses alone using linear and neural network models. We measured five channels of peripheral physiology from 20 participants – heart rate, respiration, galvanic skin response, and activity in corrugator supercilii and zygomaticus major facial muscles. Using valence and arousal (VA dimensions, participants rated their felt emotion after listening to each of 12 classical music excerpts. After extracting features from the five channels, we examined their correlation with VA ratings, and then performed multiple linear regression to see if a linear relationship between the physiological responses could account for the ratings. Although linear models predicted a significant amount of variance in arousal ratings, they were unable to do so with valence ratings. We then used a neural network to provide a nonlinear account of the ratings. The network was trained on the mean ratings of eight of the 12 excerpts and tested on the remainder. Performance of the neural network confirms that physiological responses alone can be used to predict musically induced emotion. The nonlinear model derived from the neural network was more accurate than linear models derived from multiple linear regression, particularly along the valence dimension. A secondary analysis allowed us to quantify the relative contributions of inputs to the nonlinear model. The study represents a novel approach to understanding the complex relationship between physiological responses and musically induced emotion.

  2. Amplified induced neural oscillatory activity predicts musicians' benefits in categorical speech perception.

    Science.gov (United States)

    Bidelman, Gavin M

    2017-04-21

    Event-related brain potentials (ERPs) reveal musical experience refines neural encoding and confers stronger categorical perception (CP) and neural organization for speech sounds. In addition to evoked brain activity, the human EEG can be decomposed into induced (non-phase-locked) responses whose various frequency bands reflect different mechanisms of perceptual-cognitive processing. Here, we aimed to clarify which spectral properties of these neural oscillations are most prone to music-related neuroplasticity and which are linked to behavioral benefits in the categorization of speech. We recorded electrical brain activity while musicians and nonmusicians rapidly identified speech tokens from a sound continuum. Time-frequency analysis parsed evoked and induced EEG into alpha- (∼10Hz), beta- (∼20Hz), and gamma- (>30Hz) frequency bands. We found that musicians' enhanced behavioral CP was accompanied by improved evoked speech responses across the frequency spectrum, complementing previously observed enhancements in evoked potential studies (i.e., ERPs). Brain-behavior correlations implied differences in the underlying neural mechanisms supporting speech CP in each group: modulations in induced gamma power predicted the slope of musicians' speech identification functions whereas early evoked alpha activity predicted behavior in nonmusicians. Collectively, findings indicate that musical training tunes speech processing via two complementary mechanisms: (i) strengthening the formation of auditory object representations for speech signals (gamma-band) and (ii) improving network control and/or the matching of sounds to internalized memory templates (alpha/beta-band). Both neurobiological enhancements may be deployed behaviorally and account for musicians' benefits in the perceptual categorization of speech. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Neural network remodeling underlying motor map reorganization induced by rehabilitative training after ischemic stroke.

    Science.gov (United States)

    Okabe, Naohiko; Shiromoto, Takashi; Himi, Naoyuki; Lu, Feng; Maruyama-Nakamura, Emi; Narita, Kazuhiko; Iwachidou, Nobuhisa; Yagita, Yoshiki; Miyamoto, Osamu

    2016-12-17

    Motor map reorganization is believed to be one mechanism underlying rehabilitation-induced functional recovery. Although the ipsilesional secondary motor area has been known to reorganize motor maps and contribute to rehabilitation-induced functional recovery, it is unknown how the secondary motor area is reorganized by rehabilitative training. In the present study, using skilled forelimb reaching tasks, we investigated neural network remodeling in the rat rostral forelimb area (RFA) of the secondary motor area during 4weeks of rehabilitative training. Following photothrombotic stroke in the caudal forelimb area (CFA), rehabilitative training led to task-specific recovery and motor map reorganization in the RFA. A second injury to the RFA resulted in reappearance of motor deficits. Further, when both the CFA and RFA were destroyed simultaneously, rehabilitative training no longer improved task-specific recovery. In neural tracer studies, although rehabilitative training did not alter neural projection to the RFA from other brain areas, rehabilitative training increased neural projection from the RFA to the lower spinal cord, which innervates the muscles in the forelimb. Double retrograde tracer studies revealed that rehabilitative training increased the neurons projecting from the RFA to both the upper cervical cord, which innervates the muscles in the neck, trunk, and part of the proximal forelimb, and the lower cervical cord. These results suggest that neurons projecting to the upper cervical cord provide new connections to the denervated forelimb area of the spinal cord, and these new connections may contribute to rehabilitation-induced task-specific recovery and motor map reorganization in the secondary motor area.

  4. Rejuvenation of MPTP-induced human neural precursor cell senescence by activating autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang [East Hospital, Tongji University School of Medicine, Shanghai (China); Dong, Chuanming [East Hospital, Tongji University School of Medicine, Shanghai (China); Department of Anatomy and Neurobiology, The Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong (China); Sun, Chenxi; Ma, Rongjie; Yang, Danjing [East Hospital, Tongji University School of Medicine, Shanghai (China); Zhu, Hongwen, E-mail: hongwen_zhu@hotmail.com [Tianjin Hospital, Tianjin Academy of Integrative Medicine, Tianjin (China); Xu, Jun, E-mail: xunymc2000@yahoo.com [East Hospital, Tongji University School of Medicine, Shanghai (China)

    2015-08-21

    Aging of neural stem cell, which can affect brain homeostasis, may be caused by many cellular mechanisms. Autophagy dysfunction was found in aged and neurodegenerative brains. However, little is known about the relationship between autophagy and human neural stem cell (hNSC) aging. The present study used 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) to treat neural precursor cells (NPCs) derived from human embryonic stem cell (hESC) line H9 and investigate related molecular mechanisms involved in this process. MPTP-treated NPCs were found to undergo premature senescence [determined by increased senescence-associated-β-galactosidase (SA-β-gal) activity, elevated intracellular reactive oxygen species level, and decreased proliferation] and were associated with impaired autophagy. Additionally, the cellular senescence phenotypes were manifested at the molecular level by a significant increase in p21 and p53 expression, a decrease in SOD2 expression, and a decrease in expression of some key autophagy-related genes such as Atg5, Atg7, Atg12, and Beclin 1. Furthermore, we found that the senescence-like phenotype of MPTP-treated hNPCs was rejuvenated through treatment with a well-known autophagy enhancer rapamycin, which was blocked by suppression of essential autophagy gene Beclin 1. Taken together, these findings reveal the critical role of autophagy in the process of hNSC aging, and this process can be reversed by activating autophagy. - Highlights: • We successfully establish hESC-derived neural precursor cells. • MPTP treatment induced senescence-like state in hESC-derived NPCs. • MPTP treatment induced impaired autophagy of hESC-derived NPCs. • MPTP-induced hESC-derived NPC senescence was rejuvenated by activating autophagy.

  5. Influence of selected factors on induced syneresis

    Directory of Open Access Journals (Sweden)

    Jovanović Snežana T.

    2004-01-01

    Full Text Available Syneresis is the process of whey separation induced by gel contraction resulting in rearranging or restructuring of casein matrix formed during enzymatic coagulation. Numerous factors can influence the process of syneresis. The influences of pH, calcium concentration, temperature of coagulation of milk and applied heat treatment on the syneresis induced by different intensity of centrifugal force have been investigated. Coagulated samples were centrifuged at 1000, 2000 and 3000 rpm for 5 min, respectively. Reconstituted skim milk powder (control sample and reconstituted non-fat milk heat treated at 87ºC/10 min (experimental sample are coagulated at temperatures of 30ºC and 35ºC, at pH value of 5.8 and 6.2, and with the addition of 100, 200 and 400 mg/l of CaCl2, respectively. Centrifugation at 1000 rpm of both control and experimental samples didn’t recover any sera, regardless of the applied coagulation conditions. This indicates that the intensity of centrifugal force wasn’t strong enough to disrupt gel structure and cause syneresis. When the intensity of centrifugal force was increased up to 2000 rpm, the syneresis was induced, but the degree of syneresis depended on the applied factors of coagulation, primary on the applied heat treatments and temperature of coagulation. The amount of added CaCl2 didn’t have a significant influence on the induced syneresis at 2000 rpm. The induced syneresis was very significant for both control and experimental samples when the intensity of centrifugal force of 3000 rpm was applied. It was also noted that curd produced from heat treated milk in which milk protein coaggregates were formed, released less sera regardless of the applied coagulation factors.

  6. Franck-Condon factors using supervised artificial neural networks. I. The CF+ cation.

    Science.gov (United States)

    Sandoval, Lourdes; Amero, José M; Vazquez, Gabriel J; Palma, Alejandro

    2014-06-01

    Several studies of the electronic and vibrational structure of CF(+) have been performed since this molecule was first discovered to occur in the interstellar medium, and even before that. However, researchers have paid little attention to calculating its Franck-Condon factors (FCFs), which can aid the identification of this molecule through comparison with the observed intensity spectrum. In this work, an analysis of all of the potential energy curves of CF(+) that were candidates for this kind of calculation was undertaken. The Franck-Condon factors of CF(+) were calculated using a supervised neural network with two layers and a variable learning rate.

  7. Syndromes, Disorders and Maternal Risk Factors Associated With Neural Tube Defects (VI

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2008-09-01

    Full Text Available Neural tube defects (NTDs may be associated with syndromes, disorders, and maternal and fetal risk factors. This article provides a comprehensive review of the syndromes, disorders, and maternal and fetal risk factors associated with NTDs, including maternal fumonisin consumption, periconceptional zinc deficiency, parental occupational exposure and residential proximity to pesticides, lower socioeconomic status, fetal alcohol syndrome, mutations in the VANGL1 gene, human athymic Nude/SCID fetus, and single nucleotide polymorphism in the NOS3 gene. NTDs associated with these syndromes, disorders, and maternal and fetal risk factors are a rare but important cause of NTDs. The recurrence risk and the preventive effect of maternal folic acid intake in NTDs associated with syndromes, disorders and maternal risk factors may be different from those of nonsyndromic multifactorial NTDs. Perinatal diagnosis of NTDs should alert doctors to the syndromes, disorders, and maternal and fetal risk factors associated with NTDs, and prompt thorough etiologic investigation and genetic counseling.

  8. Method of Measurement of Capacitance and Dielectric Loss Factor Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Roj Jerzy

    2015-06-01

    Full Text Available A novel method of dielectric loss factor measuring has been described. It is based on a quasi-balanced method for the capacitance measurement. These AC circuits allow to measure only one component of the impedance. However, after analyzing a quasi-balanced circuit's processing equation, it is possible to derive a novel method of dielectric loss factor measuring. Dielectric loss factor can be calculated after detuning the circuit from its quasi-equilibrium state. There are two possible ways of measuring the dielectric loss factor. In the first, the quasi-balancing of the circuit is necessary. However, it is possible to measure capacitance of an object under test. In the second method, the capacitance cannot be measured. Use of an artificial neural network minimizes errors of the loss factor determining. Simulations showed that the appropriate choice of the range of the detuning can minimize errors as well.

  9. Can the neural-cortisol association be moderated by experience-induced changes in awareness?

    Science.gov (United States)

    Lau, Way K W; Leung, Mei-Kei; Chan, Chetwyn C H; Wong, Samuel S Y; Lee, Tatia M C

    2015-11-18

    Cortisol homeostasis is important for cognitive and affective functions that depend on cortisol-sensitive brain regions including the hippocampus and prefrontal cortex. Recent studies have shown that training induces changes in the brain. We report the findings of a longitudinal study that verified the moderation effect of experience-induced changes in awareness on the neural-cortisol association in cortisol-sensitive brain regions. These findings provide the first piece of evidence that planned behavioral experience can moderate the neural-cortisol association. A range of changes in awareness was achieved in a sample of 21 Chinese participants, divided into two groups: Awareness-based compassion meditation (ABCM) (n = 10) and relaxation (n = 11). We observed that changes in awareness were significant moderators of hippocampal-cortisol changes. Furthermore, a significant negative association between changes in plasma cortisol level and the resting-state synchrony of the right hippocampal and insular-frontal-operculum regions was observed. These novel findings shed light on the inter-relationships between changes in hippocampal-cortisol levels and changes in awareness and preliminarily identify the neural underpinnings of interventions for cortisol-related abnormal functioning for further study.

  10. Early life allergen-induced mucus overproduction requires augmented neural stimulation of pulmonary neuroendocrine cell secretion.

    Science.gov (United States)

    Barrios, Juliana; Patel, Kruti R; Aven, Linh; Achey, Rebecca; Minns, Martin S; Lee, Yoonjoo; Trinkaus-Randall, Vickery E; Ai, Xingbin

    2017-09-01

    Pulmonary neuroendocrine cells (PNECs) are the only innervated airway epithelial cells. To what extent neural innervation regulates PNEC secretion and function is unknown. Here, we discover that neurotrophin 4 (NT4) plays an essential role in mucus overproduction after early life allergen exposure by orchestrating PNEC innervation and secretion of GABA. We found that PNECs were the only cellular source of GABA in airways. In addition, PNECs expressed NT4 as a target-derived mechanism underlying PNEC innervation during development. Early life allergen exposure elevated the level of NT4 and caused PNEC hyperinnervation and nodose neuron hyperactivity. Associated with aberrant PNEC innervation, the authors discovered that GABA hypersecretion was required for the induction of mucin Muc5ac expression. In contrast, NT4(-/-) mice were protected from allergen-induced mucus overproduction and changes along the nerve-PNEC axis without any defects in inflammation. Last, GABA installation restored mucus overproduction in NT4(-/-) mice after early life allergen exposure. Together, our findings provide the first evidence for NT4-dependent neural regulation of PNEC secretion of GABA in a neonatal disease model. Targeting the nerve-PNEC axis may be a valid treatment strategy for mucus overproduction in airway diseases, such as childhood asthma.-Barrios, J., Patel, K. R., Aven, L., Achey, R., Minns, M. S., Lee, Y., Trinkaus-Randall, V. E., Ai, X. Early life allergen-induced mucus overproduction requires augmented neural stimulation of pulmonary neuroendocrine cell secretion. © FASEB.

  11. Radiation-induced glioblastoma signaling cascade regulates viability, apoptosis and differentiation of neural stem cells (NSC).

    Science.gov (United States)

    Ivanov, Vladimir N; Hei, Tom K

    2014-12-01

    Ionizing radiation alone or in combination with chemotherapy is the main treatment modality for brain tumors including glioblastoma. Adult neurons and astrocytes demonstrate substantial radioresistance; in contrast, human neural stem cells (NSC) are highly sensitive to radiation via induction of apoptosis. Irradiation of tumor cells has the potential risk of affecting the viability and function of NSC. In this study, we have evaluated the effects of irradiated glioblastoma cells on viability, proliferation and differentiation potential of non-irradiated (bystander) NSC through radiation-induced signaling cascades. Using media transfer experiments, we demonstrated significant effects of the U87MG glioblastoma secretome after gamma-irradiation on apoptosis in non-irradiated NSC. Addition of anti-TRAIL antibody to the transferred media partially suppressed apoptosis in NSC. Furthermore, we observed a dramatic increase in the production and secretion of IL8, TGFβ1 and IL6 by irradiated glioblastoma cells, which could promote glioblastoma cell survival and modify the effects of death factors in bystander NSC. While differentiation of NSC into neurons and astrocytes occurred efficiently with the corresponding differentiation media, pretreatment of NSC for 8 h with medium from irradiated glioblastoma cells selectively suppressed the differentiation of NSC into neurons, but not into astrocytes. Exogenous IL8 and TGFβ1 increased NSC/NPC survival, but also suppressed neuronal differentiation. On the other hand, IL6 was known to positively affect survival and differentiation of astrocyte progenitors. We established a U87MG neurosphere culture that was substantially enriched by SOX2(+) and CD133(+) glioma stem-like cells (GSC). Gamma-irradiation up-regulated apoptotic death in GSC via the FasL/Fas pathway. Media transfer experiments from irradiated GSC to non-targeted NSC again demonstrated induction of apoptosis and suppression of neuronal differentiation of NSC. In

  12. Ectopic Myf5 or MyoD prevents the neuronal differentiation program in addition to inducing skeletal muscle differentiation, in the chick neural tube.

    Science.gov (United States)

    Delfini, Marie-Claire; Duprez, Delphine

    2004-02-01

    Forced expression of the bHLH myogenic factors, Myf5 and MyoD, in various mammalian cell lines induces the full program of myogenic differentiation. However, this property has not been extensively explored in vivo. We have taken advantage of the chick model to investigate the effect of electroporation of the mouse Myf5 and MyoD genes in the embryonic neural tube. We found that misexpression of either mouse Myf5 or MyoD in the chick neural tube leads to ectopic skeletal muscle differentiation, assayed by the expression of the myosin heavy chains in the neural tube and neural crest derivatives. We also showed that the endogenous neuronal differentiation program is inhibited under the influence of either ectopic mouse Myf5 or MyoD. We used this new system to analyse, in vivo, the transcriptional regulation between the myogenic factors. We found that MyoD and Myogenin expression can be activated by ectopic mouse Myf5 or MyoD, while Myf5 expression cannot be activated either by mouse MyoD or by itself. We also analysed the transcriptional regulation between the myogenic factors and the different genes involved in myogenesis, such as Mef2c, Pax3, Paraxis, Six1, Mox1, Mox2 and FgfR4. We established the existence of an unexpected regulatory loop between MyoD and FgfR4. The consequences for myogenesis are discussed.

  13. Neural and Behavioral Correlates of Alcohol-Induced Aggression Under Provocation.

    Science.gov (United States)

    Gan, Gabriela; Sterzer, Philipp; Marxen, Michael; Zimmermann, Ulrich S; Smolka, Michael N

    2015-12-01

    Although alcohol consumption is linked to increased aggression, its neural correlates have not directly been studied in humans so far. Based on a comprehensive neurobiological model of alcohol-induced aggression, we hypothesized that alcohol-induced aggression would go along with increased amygdala and ventral striatum reactivity and impaired functioning of the prefrontal cortex (PFC) under alcohol. We measured neural and behavioral correlates of alcohol-induced aggression in a provoking vs non-provoking condition with a variant of the Taylor aggression paradigm (TAP) allowing to differentiate between reactive (provoked) and proactive (unprovoked) aggression. In a placebo-controlled cross-over design with moderate alcohol intoxication (~0.6 g/kg), 35 young healthy adults performed the TAP during functional magnetic resonance imaging (fMRI). Analyses revealed that provoking vs non-provoking conditions and alcohol vs placebo increased aggression and decreased brain responses in the anterior cingulate cortex/dorso-medial PFC (provokingaggression (alcohol × provocation interaction). However, investigation of inter-individual differences revealed (1) that pronounced alcohol-induced proactive aggression was linked to higher levels of aggression under placebo, and (2) that pronounced alcohol-induced reactive aggression was related to increased amygdala and ventral striatum reactivity under alcohol, providing evidence for their role in human alcohol-induced reactive aggression. Our findings suggest that in healthy young adults a liability for alcohol-induced aggression in a non-provoking context might depend on overall high levels of aggression, but on alcohol-induced increased striatal and amygdala reactivity when triggered by provocation.

  14. True and False Recognition Memories of Odors Induce Distinct Neural Signatures

    Science.gov (United States)

    Royet, Jean-Pierre; Morin-Audebrand, Léri; Cerf-Ducastel, Barbara; Haase, Lori; Issanchou, Sylvie; Murphy, Claire; Fonlupt, Pierre; Sulmont-Rossé, Claire; Plailly, Jane

    2011-01-01

    Neural bases of human olfactory memory are poorly understood. Very few studies have examined neural substrates associated with correct odor recognition, and none has tackled neural networks associated with incorrect odor recognition. We investigated the neural basis of task performance during a yes–no odor recognition memory paradigm in young and elderly subjects using event-related functional magnetic resonance imaging. We explored four response categories: correct (Hit) and incorrect false alarm (FA) recognition, as well as correct (CR) and incorrect (Miss) rejection, and we characterized corresponding brain responses using multivariate analysis and linear regression analysis. We hypothesized that areas of the medial temporal lobe were differentially involved depending on the accuracy of odor recognition. In young adults, we found that significant activity in the hippocampus and the parahippocampal gyrus was associated with correct (true) recognition of odors, whereas the perirhinal cortex was associated with FAs and Misses. These findings are consistent with literature regarding hypothetical functional organization for memory processing. We also found that for correct recognition and rejection responses, the involvement of the hippocampus decreased when memory performances improved. In contrast to young individuals, elderly subjects were more prone to false memories and exhibited less specific activation patterns for the four response categories. Activation in the hippocampus and the parahippocampal gyrus was positively correlated with response bias scores for true and false recognition, demonstrating that conservative subjects produced an additional search effort leading to more activation of these two medial temporal lobe regions. These findings demonstrate that correct and incorrect recognition and rejection induce distinct neural signatures. PMID:21811450

  15. True and false recognition memories of odors induce distinct neural signatures

    Directory of Open Access Journals (Sweden)

    Jean-Pierre eRoyet

    2011-07-01

    Full Text Available Neural bases of human olfactory memory are poorly understood. Very few studies have examined neural substrates associated with correct odor recognition, and none has tackled neural networks associated with incorrect odor recognition. We investigated the neural basis of task performance during a yes-no odor recognition memory paradigm in young and elderly subjects using event-related functional magnetic resonance imaging. We explored four response categories: correct (Hit and incorrect (False Alarm recognition, as well as correct (CR and incorrect (Miss rejection, and we characterized corresponding brain responses using multivariate analysis and linear regression analysis. We hypothesized that areas of the medial temporal lobe were differentially involved depending on the accuracy of odor recognition. In young adults, we found that significant activity in the hippocampus and the parahippocampal gyrus was associated with correct (true recognition of odors, whereas the perirhinal cortex was associated with False Alarms and Misses. These findings are consistent with literature regarding hypothetical functional organization for memory processing. We also found that for correct recognition and rejection responses, the involvement of the hippocampus decreased when memory performances improved. In contrast to young individuals, elderly subjects were more prone to false memories and exhibited less specific activation patterns for the four response categories. Activation in the hippocampus and the parahippocampal gyrus was positively correlated with response bias scores for true and false recognition, demonstrating that conservative subjects produced an additional search effort leading to more activation of these two medial temporal lobe regions. These findings demonstrate that correct and incorrect recognition and rejection induce distinct neural signatures.

  16. Comparative sensitivity of human and rat neural cultures to chemical-induced inhibition of neurite outgrowth

    Energy Technology Data Exchange (ETDEWEB)

    Harrill, Joshua A.; Freudenrich, Theresa M.; Robinette, Brian L.; Mundy, William R., E-mail: mundy.william@epa.gov

    2011-11-15

    There is a need for rapid, efficient and cost-effective alternatives to traditional in vivo developmental neurotoxicity testing. In vitro cell culture models can recapitulate many of the key cellular processes of nervous system development, including neurite outgrowth, and may be used as screening tools to identify potential developmental neurotoxicants. The present study compared primary rat cortical cultures and human embryonic stem cell-derived neural cultures in terms of: 1) reproducibility of high content image analysis based neurite outgrowth measurements, 2) dynamic range of neurite outgrowth measurements and 3) sensitivity to chemicals which have been shown to inhibit neurite outgrowth. There was a large increase in neurite outgrowth between 2 and 24 h in both rat and human cultures. Image analysis data collected across multiple cultures demonstrated that neurite outgrowth measurements in rat cortical cultures were more reproducible and had higher dynamic range as compared to human neural cultures. Human neural cultures were more sensitive than rat cortical cultures to chemicals previously shown to inhibit neurite outgrowth. Parallel analysis of morphological (neurite count, neurite length) and cytotoxicity (neurons per field) measurements were used to detect selective effects on neurite outgrowth. All chemicals which inhibited neurite outgrowth in rat cortical cultures did so at concentrations which did not concurrently affect the number of neurons per field, indicating selective effects on neurite outgrowth. In contrast, more than half the chemicals which inhibited neurite outgrowth in human neural cultures did so at concentrations which concurrently decreased the number of neurons per field, indicating that effects on neurite outgrowth were secondary to cytotoxicity. Overall, these data demonstrate that the culture models performed differently in terms of reproducibility, dynamic range and sensitivity to neurite outgrowth inhibitors. While human neural

  17. Extended passaging increases the efficiency of neural differentiation from induced pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Koehler Karl R

    2011-08-01

    Full Text Available Abstract Background The use of induced pluripotent stem cells (iPSCs for the functional replacement of damaged neurons and in vitro disease modeling is of great clinical relevance. Unfortunately, the capacity of iPSC lines to differentiate into neurons is highly variable, prompting the need for a reliable means of assessing the differentiation capacity of newly derived iPSC cell lines. Extended passaging is emerging as a method of ensuring faithful reprogramming. We adapted an established and efficient embryonic stem cell (ESC neural induction protocol to test whether iPSCs (1 have the competence to give rise to functional neurons with similar efficiency as ESCs and (2 whether the extent of neural differentiation could be altered or enhanced by increased passaging. Results Our gene expression and morphological analyses revealed that neural conversion was temporally delayed in iPSC lines and some iPSC lines did not properly form embryoid bodies during the first stage of differentiation. Notably, these deficits were corrected by continual passaging in an iPSC clone. iPSCs with greater than 20 passages (late-passage iPSCs expressed higher expression levels of pluripotency markers and formed larger embryoid bodies than iPSCs with fewer than 10 passages (early-passage iPSCs. Moreover, late-passage iPSCs started to express neural marker genes sooner than early-passage iPSCs after the initiation of neural induction. Furthermore, late-passage iPSC-derived neurons exhibited notably greater excitability and larger voltage-gated currents than early-passage iPSC-derived neurons, although these cells were morphologically indistinguishable. Conclusions These findings strongly suggest that the efficiency neuronal conversion depends on the complete reprogramming of iPSCs via extensive passaging.

  18. Perinatal factors associated with neural tube defects (anencephaly [correction of anancephaly], spina bifida and encephalocele).

    Science.gov (United States)

    Ogata, A J; Camano, L; Brunoni, D

    1992-01-01

    The objective of the present study was to determine the presence of risk factors for the occurrence of neural tube defects. Data for 33,535 births which occurred at Hospital do Servidor Público Estadual de São Paulo from July 1973 to December 1986 were collected in a prospective manner as recommended by "Estudo Colaborativo Latino-Americano de Malformações Congênitas" (ECLAMC, Collaborative Latin American Study on Congenital Malformations). Twenty-six cases of neural tube defects were detected (0.77/1000 births). Of these, 11 were cases of spina bifida (0.39/1000 births), 9 of anencephaly (0.27/1000 births) and 6 of encephalocele (0.18/1000 births). We observed a higher frequency of polyhydramnios, premature labor, Apgar scores of less than 7 at the first and fifth minutes, low birth weight and intrauterine growth retardation.

  19. An intelligent power factor corrector for power system using artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Bayindir, R.; Colak, I. [Department of Electrical Education, Faculty of Technical Education, Gazi University, Besevler, 06500 Ankara (Turkey); Sagiroglu, S. [Department of Computer Engineering, Faculty of Engineering and Architecture, Celal Bayar Bulvari, Gazi University, Maltepe, 06570 Ankara (Turkey)

    2009-01-15

    An intelligent power factor correction approach based on artificial neural networks (ANN) is introduced. Four learning algorithms, backpropagation (BP), delta-bar-delta (DBD), extended delta-bar-delta (EDBD) and directed random search (DRS), were used to train the ANNs. The best test results obtained from the ANN compensators trained with the four learning algorithms were first achieved. The parameters belonging to each neural compensator obtained from an off-line training were then inserted into a microcontroller for on-line usage. The results have shown that the selected intelligent compensators developed in this work might overcome the problems occurred in the literature providing accurate, simple and low-cost solution for compensation. (author)

  20. Vascular Endothelial Growth Factor Receptor 3 Controls Neural Stem Cell Activation in Mice and Humans

    Directory of Open Access Journals (Sweden)

    Jinah Han

    2015-02-01

    Full Text Available Neural stem cells (NSCs continuously produce new neurons within the adult mammalian hippocampus. NSCs are typically quiescent but activated to self-renew or differentiate into neural progenitor cells. The molecular mechanisms of NSC activation remain poorly understood. Here, we show that adult hippocampal NSCs express vascular endothelial growth factor receptor (VEGFR 3 and its ligand VEGF-C, which activates quiescent NSCs to enter the cell cycle and generate progenitor cells. Hippocampal NSC activation and neurogenesis are impaired by conditional deletion of Vegfr3 in NSCs. Functionally, this is associated with compromised NSC activation in response to VEGF-C and physical activity. In NSCs derived from human embryonic stem cells (hESCs, VEGF-C/VEGFR3 mediates intracellular activation of AKT and ERK pathways that control cell fate and proliferation. These findings identify VEGF-C/VEGFR3 signaling as a specific regulator of NSC activation and neurogenesis in mammals.

  1. Identification and discrimination of bacterial strains by laser induced breakdown spectroscopy and neural networks.

    Science.gov (United States)

    Marcos-Martinez, D; Ayala, J A; Izquierdo-Hornillos, R C; de Villena, F J Manuel; Caceres, J O

    2011-05-15

    A method based on laser induced breakdown spectroscopy (LIBS) and neural networks (NNs) has been developed and applied to the identification and discrimination of specific bacteria strains (Pseudomonas aeroginosa, Escherichia coli and Salmonella typhimurium). Instant identification of the samples is achieved using a spectral library, which was obtained by analysis using a single laser pulse of representative samples and treatment by neural networks. The samples used in this study were divided into three groups, which were prepared on three different days. The results obtained allow the identification of the bacteria tested with a certainty of over 95%, and show that only a difference between the bacteria can cause identification. Single-shot measurements were sufficient for clear identification of the bacterial strains studied. The method can be developed for automatic real time, fast, reliable and robust measurements and can be packaged in portable systems for non-specialist users. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Neural stem cells induce the formation of their physical niche during organogenesis.

    Science.gov (United States)

    Seleit, Ali; Krämer, Isabel; Riebesehl, Bea F; Ambrosio, Elizabeth M; Stolper, Julian S; Lischik, Colin Q; Dross, Nicolas; Centanin, Lazaro

    2017-09-27

    Most organs rely on stem cells to maintain homeostasis during post-embryonic life. Typically, stem cells of independent lineages work coordinately within mature organs to ensure proper ratios of cell types. Little is known, however, on how these different stem cells locate to forming organs during development. Here we show that neuromasts of the posterior lateral line in medaka are composed of two independent life-long lineages with different embryonic origins. Clonal analysis and 4D imaging revealed a hierarchical organisation with instructing and responding roles: an inner, neural lineage induces the formation of an outer, border cell lineage (nBC) from the skin epithelium. Our results demonstrate that the neural lineage is necessary and sufficient to generate nBCs highlighting self-organisation principles at the level of the entire embryo. We hypothesise that induction of surrounding tissues plays a major role during the establishment of vertebrate stem cell niches.

  3. Carbon nanotube-collagen three-dimensional culture of mesenchymal stem cells promotes expression of neural phenotypes and secretion of neurotrophic factors.

    Science.gov (United States)

    Lee, Jae Ho; Lee, Ja-Yeon; Yang, Sung Hee; Lee, Eun-Jung; Kim, Hae-Won

    2014-10-01

    Microenvironments provided by three-dimensional (3-D) hydrogels mimic native tissue conditions, supplying appropriate physical cues for regulating stem cell behaviors. Here, we focused on carbon nanotubes (CNTs) dispersed within collagen hydrogels to provide 3-D microenvironmental conditions for mesenchymal stem cells (MSCs) in stimulating biological functions for neural regeneration. Small concentrations of CNTs (0.1-1wt.%) did not induce toxicity to MSCs, and even improved the proliferative potential of the cells. MSCs cultured within the CNT-collagen hydrogel expressed considerable levels of neural markers, including GAP43 and βIII tubulin proteins by immunostaining as well as GAP43 and synapse I genes by reverse transcriptase polymerase chain reaction (RT-PCR). Of note was that neurotrophic factors, particularly nerve growth factor and brain derived neurotrophic factor, were significantly promoted by the incorporation of CNTs as confirmed by RT-PCR and Western blot analysis. A model experiment involving neuritogenesis of PC12 cells influenced by those releasing neurotrophic factors from MSCs cultured within the CNT-collagen hydrogel demonstrated the significant enhancement in neurite outgrowth behaviors. Taken together, collagen hydrogel provides excellent 3-D conditions for MSC growth, and a small incorporation of CNTs within the hydrogel significantly stimulates MSC expression of neural markers and secretion of neurotrophic factors.

  4. Autophagy protects against neural cell death induced by piperidine alkaloids present in Prosopis juliflora (Mesquite

    Directory of Open Access Journals (Sweden)

    VICTOR D.A. SILVA

    Full Text Available ABSTRACT Prosopis juliflora is a shrub that has been used to feed animals and humans. However, a synergistic action of piperidine alkaloids has been suggested to be responsible for neurotoxic damage observed in animals. We investigated the involvement of programmed cell death (PCD and autophagy on the mechanism of cell death induced by a total extract (TAE of alkaloids and fraction (F32 from P. juliflora leaves composed majoritary of juliprosopine in a model of neuron/glial cell co-culture. We saw that TAE (30 µg/mL and F32 (7.5 µg/mL induced reduction in ATP levels and changes in mitochondrial membrane potential at 12 h exposure. Moreover, TAE and F32 induced caspase-9 activation, nuclear condensation and neuronal death at 16 h exposure. After 4 h, they induced autophagy characterized by decreases of P62 protein level, increase of LC3II expression and increase in number of GFP-LC3 cells. Interestingly, we demonstrated that inhibition of autophagy by bafilomycin and vinblastine increased the cell death induced by TAE and autophagy induced by serum deprivation and rapamycin reduced cell death induced by F32 at 24 h. These results indicate that the mechanism neural cell death induced by these alkaloids involves PCD via caspase-9 activation and autophagy, which seems to be an important protective mechanism.

  5. Prediction of friction factor of pure water flowing inside vertical smooth and microfin tubes by using artificial neural networks

    Science.gov (United States)

    Çebi, A.; Akdoğan, E.; Celen, A.; Dalkilic, A. S.

    2017-02-01

    An artificial neural network (ANN) model of friction factor in smooth and microfin tubes under heating, cooling and isothermal conditions was developed in this study. Data used in ANN was taken from a vertically positioned heat exchanger experimental setup. Multi-layered feed-forward neural network with backpropagation algorithm, radial basis function networks and hybrid PSO-neural network algorithm were applied to the database. Inputs were the ratio of cross sectional flow area to hydraulic diameter, experimental condition number depending on isothermal, heating, or cooling conditions and mass flow rate while the friction factor was the output of the constructed system. It was observed that such neural network based system could effectively predict the friction factor values of the flows regardless of their tube types. A dependency analysis to determine the strongest parameter that affected the network and database was also performed and tube geometry was found to be the strongest parameter of all as a result of analysis.

  6. Prediction of friction factor of pure water flowing inside vertical smooth and microfin tubes by using artificial neural networks

    Science.gov (United States)

    Çebi, A.; Akdoğan, E.; Celen, A.; Dalkilic, A. S.

    2016-06-01

    An artificial neural network (ANN) model of friction factor in smooth and microfin tubes under heating, cooling and isothermal conditions was developed in this study. Data used in ANN was taken from a vertically positioned heat exchanger experimental setup. Multi-layered feed-forward neural network with backpropagation algorithm, radial basis function networks and hybrid PSO-neural network algorithm were applied to the database. Inputs were the ratio of cross sectional flow area to hydraulic diameter, experimental condition number depending on isothermal, heating, or cooling conditions and mass flow rate while the friction factor was the output of the constructed system. It was observed that such neural network based system could effectively predict the friction factor values of the flows regardless of their tube types. A dependency analysis to determine the strongest parameter that affected the network and database was also performed and tube geometry was found to be the strongest parameter of all as a result of analysis.

  7. A Hydrogel Bridge Incorporating Immobilized Growth Factors and Neural Stem/Progenitor Cells to Treat Spinal Cord Injury.

    Science.gov (United States)

    Li, Hang; Ham, Trevor R; Neill, Nicholas; Farrag, Mahmoud; Mohrman, Ashley E; Koenig, Andrew M; Leipzig, Nic D

    2016-04-06

    Spinal cord injury (SCI) causes permanent, often complete disruption of central nervous system (CNS) function below the damaged region, leaving patients without the ability to regenerate lost tissue. To engineer new CNS tissue, a unique spinal cord bridge is created to deliver stem cells and guide their organization and development with site-specifically immobilized growth factors. In this study, this bridge is tested, consisting of adult neural stem/progenitor cells contained within a methacrylamide chitosan (MAC) hydrogel and protected by a chitosan conduit. Interferon-γ (IFN-γ) and platelet-derived growth factor-AA (PDGF-AA) are recombinantly produced and tagged with an N-terminal biotin. They are immobilized to streptavidin-functionalized MAC to induce either neuronal or oligodendrocytic lineages, respectively. These bridges are tested in a rat hemisection model of SCI between T8 and T9. After eight weeks treatments including chitosan conduits result in a significant reduction in lesion area and macrophage infiltration around the lesion site (p < 0.0001). Importantly, neither immobilized IFN-γ nor PDGF-AA increased macrophage infiltration. Retrograde tracing demonstrates improved neuronal regeneration through the use of immobilized growth factors. Immunohistochemistry staining demonstrates that immobilized growth factors are effective in differentiating encapsulated cells into their anticipated lineages within the hydrogel, while qualitatively reducing glial fibrillary acid protein expression.

  8. Diverse ETS transcription factors mediate FGF signaling in the Ciona anterior neural plate.

    Science.gov (United States)

    Gainous, T Blair; Wagner, Eileen; Levine, Michael

    2015-03-15

    The ascidian Ciona intestinalis is a marine invertebrate belonging to the sister group of the vertebrates, the tunicates. Its compact genome and simple, experimentally tractable embryos make Ciona well-suited for the study of cell-fate specification in chordates. Tunicate larvae possess a characteristic chordate body plan, and many developmental pathways are conserved between tunicates and vertebrates. Previous studies have shown that FGF signals are essential for neural induction and patterning at sequential steps of Ciona embryogenesis. Here we show that two different ETS family transcription factors, Ets1/2 and Elk1/3/4, have partially redundant activities in the anterior neural plate of gastrulating embryos. Whereas Ets1/2 promotes pigment cell formation in lateral lineages, both Ets1/2 and Elk1/3/4 are involved in the activation of Myt1L in medial lineages and the restriction of Six3/6 expression to the anterior-most regions of the neural tube. We also provide evidence that photoreceptor cells arise from posterior regions of the presumptive sensory vesicle, and do not depend on FGF signaling. Cells previously identified as photoreceptor progenitors instead form ependymal cells and neurons of the larval brain. Our results extend recent findings on FGF-dependent patterning of anterior-posterior compartments in the Ciona central nervous system. Copyright © 2015. Published by Elsevier Inc.

  9. Environmental factors unveil dormant developmental capacities in multipotent progenitors of the trunk neural crest.

    Science.gov (United States)

    Coelho-Aguiar, Juliana M; Le Douarin, Nicole M; Dupin, Elisabeth

    2013-12-01

    The neural crest (NC), an ectoderm-derived structure of the vertebrate embryo, gives rise to the melanocytes, most of the peripheral nervous system and the craniofacial mesenchymal tissues (i.e., connective, bone, cartilage and fat cells). In the trunk of Amniotes, no mesenchymal tissues are derived from the NC. In certain in vitro conditions however, avian and murine trunk NC cells (TNCCs) displayed a limited mesenchymal differentiation capacity. Whether this capacity originates from committed precursors or from multipotent TNCCs was unknown. Here, we further investigated the potential of TNCCs to develop into mesenchymal cell types in vitro. We found that, in fact, quail TNCCs exhibit a high ability to differentiate into myofibroblasts, chondrocytes, lipid-laden adipocytes and mineralizing osteoblasts. In single cell cultures, both mesenchymal and neural cell types coexisted in TNCC clonal progeny: 78% of single cells yielded osteoblasts together with glial cells and neurons; moreover, TNCCs generated heterogenous clones with adipocytes, myofibroblasts, melanocytes and/or glial cells. Therefore, alike cephalic NCCs, early migratory TNCCs comprised multipotent progenitors able to generate both mesenchymal and melanocytic/neural derivatives, suggesting a continuum in NC developmental potentials along the neural axis. The skeletogenic capacity of the TNC, which was present in the exoskeletal armor of the extinct basal forms of Vertebrates and which persisted in the distal fin rays of extant teleost fish, thus did not totally disappear during vertebrate evolution. Mesenchymal potentials of the TNC, although not fulfilled during development, are still present in a dormant state in Amniotes and can be disclosed in in vitro culture. Whether these potentials are not expressed in vivo due to the presence of inhibitory cues or to the lack of permissive factors in the trunk environment remains to be understood. © 2013 Published by Elsevier Inc.

  10. Infrared neural stimulation induces intracellular Ca(2+) release mediated by phospholipase C.

    Science.gov (United States)

    Moreau, David; Lefort, Claire; Pas, Jolien; Bardet, Sylvia M; Leveque, Philippe; O'Connor, Rodney P

    2017-07-12

    The influence of infrared laser pulses on intracellular Ca(2+) signaling was investigated in neural cell lines with fluorescent live cell imaging. The probe Fluo-4 was used to measure Ca(2+) in HT22 mouse hippocampal neurons and nonelectrically excitable U87 human glioblastoma cells exposed to 50 to 500 ms infrared pulses at 1470 nm. Fluorescence recordings of Fluo-4 demonstrated that infrared stimulation induced an instantaneous intracellular Ca(2+) transient with similar dose-response characteristics in hippocampal neurons and glioblastoma cells (half-maximal effective energy density EC50 of around 58 J.cm(-2) ). For both type of cells, the source of the infrared-induced Ca(2+) transients was found to originate from intracellular stores and to be mediated by phospholipase C and IP3 -induced Ca(2+) release from the endoplasmic reticulum. The activation of phosphoinositide signaling by IR light is a new mechanism of interaction relevant to infrared neural stimulation that will also be widely applicable to nonexcitable cell types. The prospect of infrared optostimulation of the PLC/IP3 cell signaling cascade has many potential applications including the development of optoceutical therapeutics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Neural correlates of cognitive dissonance and choice-induced preference change.

    Science.gov (United States)

    Izuma, Keise; Matsumoto, Madoka; Murayama, Kou; Samejima, Kazuyuki; Sadato, Norihiro; Matsumoto, Kenji

    2010-12-21

    According to many modern economic theories, actions simply reflect an individual's preferences, whereas a psychological phenomenon called "cognitive dissonance" claims that actions can also create preference. Cognitive dissonance theory states that after making a difficult choice between two equally preferred items, the act of rejecting a favorite item induces an uncomfortable feeling (cognitive dissonance), which in turn motivates individuals to change their preferences to match their prior decision (i.e., reducing preference for rejected items). Recently, however, Chen and Risen [Chen K, Risen J (2010) J Pers Soc Psychol 99:573-594] pointed out a serious methodological problem, which casts a doubt on the very existence of this choice-induced preference change as studied over the past 50 y. Here, using a proper control condition and two measures of preferences (self-report and brain activity), we found that the mere act of making a choice can change self-report preference as well as its neural representation (i.e., striatum activity), thus providing strong evidence for choice-induced preference change. Furthermore, our data indicate that the anterior cingulate cortex and dorsolateral prefrontal cortex tracked the degree of cognitive dissonance on a trial-by-trial basis. Our findings provide important insights into the neural basis of how actions can alter an individual's preferences.

  12. Prediction of blast-induced flyrock in Indian limestone mines using neural networks

    Directory of Open Access Journals (Sweden)

    R. Trivedi

    2014-10-01

    Full Text Available Frequency and scale of the blasting events are increasing to boost limestone production. Mines are approaching close to inhabited areas due to growing population and limited availability of land resources which has challenged the management to go for safe blasts with special reference to opencast mining. The study aims to predict the distance covered by the flyrock induced by blasting using artificial neural network (ANN and multi-variate regression analysis (MVRA for better assessment. Blast design and geotechnical parameters, such as linear charge concentration, burden, stemming length, specific charge, unconfined compressive strength (UCS, and rock quality designation (RQD, have been selected as input parameters and flyrock distance used as output parameter. ANN has been trained using 95 datasets of experimental blasts conducted in 4 opencast limestone mines in India. Thirty datasets have been used for testing and validation of trained neural network. Flyrock distances have been predicted by ANN, MVRA, as well as further calculated using motion analysis of flyrock projectiles and compared with the observed data. Back propagation neural network (BPNN has been proven to be a superior predictive tool when compared with MVRA.

  13. Mindful attention reduces neural and self-reported cue-induced craving in smokers

    Science.gov (United States)

    Creswell, John David; Tabibnia, Golnaz; Julson, Erica; Kober, Hedy; Tindle, Hilary A.

    2013-01-01

    An emerging body of research suggests that mindfulness-based interventions may be beneficial for smoking cessation and the treatment of other addictive disorders. One way that mindfulness may facilitate smoking cessation is through the reduction of craving to smoking cues. The present work considers whether mindful attention can reduce self-reported and neural markers of cue-induced craving in treatment seeking smokers. Forty-seven (n = 47) meditation-naïve treatment-seeking smokers (12-h abstinent from smoking) viewed and made ratings of smoking and neutral images while undergoing functional magnetic resonance imaging (fMRI). Participants were trained and instructed to view these images passively or with mindful attention. Results indicated that mindful attention reduced self-reported craving to smoking images, and reduced neural activity in a craving-related region of subgenual anterior cingulate cortex (sgACC). Moreover, a psychophysiological interaction analysis revealed that mindful attention reduced functional connectivity between sgACC and other craving-related regions compared to passively viewing smoking images, suggesting that mindfulness may decouple craving neurocircuitry when viewing smoking cues. These results provide an initial indication that mindful attention may describe a ‘bottom-up’ attention to one’s present moment experience in ways that can help reduce subjective and neural reactivity to smoking cues in smokers. PMID:22114078

  14. Genomic DNA hypomethylation is associated with neural tube defects induced by methotrexate inhibition of folate metabolism.

    Directory of Open Access Journals (Sweden)

    Xiuwei Wang

    Full Text Available DNA methylation is thought to be involved in the etiology of neural tube defects (NTDs. However, the exact mechanism between DNA methylation and NTDs remains unclear. Herein, we investigated the change of methylation in mouse model of NTDs associated with folate dysmetabolism by use of ultraperformance liquid chromatography tandem mass spectrometry (UPLC/MS/MS, liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS, microarray, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and Real time quantitative PCR. Results showed that NTD neural tube tissues had lower concentrations of 5-methyltetrahydrofolate (5-MeTHF, P = 0.005, 5-formyltetrahydrofolate (5-FoTHF, P = 0.040, S-adenosylmethionine (SAM, P = 0.004 and higher concentrations of folic acid (P = 0.041, homocysteine (Hcy, P = 0.006 and S-adenosylhomocysteine (SAH, P = 0.045 compared to control. Methylation levels of genomic DNA decreased significantly in the embryonic neural tube tissue of NTD samples. 132 differentially methylated regions (35 low methylated regions and 97 high methylated regions were selected by microarray. Two genes (Siah1b, Prkx in Wnt signal pathway demonstrated lower methylated regions (peak and higher expression in NTDs (P<0.05; P<0.05. Results suggest that DNA hypomethylation was one of the possible epigenetic variations correlated with the occurrence of NTDs induced by folate dysmetabolism and that Siah1b, Prkx in Wnt pathway may be candidate genes for NTDs.

  15. Genomic DNA hypomethylation is associated with neural tube defects induced by methotrexate inhibition of folate metabolism.

    Science.gov (United States)

    Wang, Xiuwei; Guan, Zhen; Chen, Yan; Dong, Yanting; Niu, Yuhu; Wang, Jianhua; Zhang, Ting; Niu, Bo

    2015-01-01

    DNA methylation is thought to be involved in the etiology of neural tube defects (NTDs). However, the exact mechanism between DNA methylation and NTDs remains unclear. Herein, we investigated the change of methylation in mouse model of NTDs associated with folate dysmetabolism by use of ultraperformance liquid chromatography tandem mass spectrometry (UPLC/MS/MS), liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS), microarray, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and Real time quantitative PCR. Results showed that NTD neural tube tissues had lower concentrations of 5-methyltetrahydrofolate (5-MeTHF, P = 0.005), 5-formyltetrahydrofolate (5-FoTHF, P = 0.040), S-adenosylmethionine (SAM, P = 0.004) and higher concentrations of folic acid (P = 0.041), homocysteine (Hcy, P = 0.006) and S-adenosylhomocysteine (SAH, P = 0.045) compared to control. Methylation levels of genomic DNA decreased significantly in the embryonic neural tube tissue of NTD samples. 132 differentially methylated regions (35 low methylated regions and 97 high methylated regions) were selected by microarray. Two genes (Siah1b, Prkx) in Wnt signal pathway demonstrated lower methylated regions (peak) and higher expression in NTDs (P<0.05; P<0.05). Results suggest that DNA hypomethylation was one of the possible epigenetic variations correlated with the occurrence of NTDs induced by folate dysmetabolism and that Siah1b, Prkx in Wnt pathway may be candidate genes for NTDs.

  16. Prediction of blast-induced flyrock in Indian limestone mines using neural networks

    Institute of Scientific and Technical Information of China (English)

    R. Trivedi; T.N. Singh; A.K. Raina

    2014-01-01

    Frequency and scale of the blasting events are increasing to boost limestone production. Mines are approaching close to inhabited areas due to growing population and limited availability of land resources which has challenged the management to go for safe blasts with special reference to opencast mining. The study aims to predict the distance covered by the flyrock induced by blasting using artificial neural network (ANN) and multi-variate regression analysis (MVRA) for better assessment. Blast design and geotechnical parameters, such as linear charge concentration, burden, stemming length, specific charge, unconfined compressive strength (UCS), and rock quality designation (RQD), have been selected as input parameters and flyrock distance used as output parameter. ANN has been trained using 95 datasets of experimental blasts conducted in 4 opencast limestone mines in India. Thirty datasets have been used for testing and validation of trained neural network. Flyrock distances have been predicted by ANN, MVRA, as well as further calculated using motion analysis of flyrock projectiles and compared with the observed data. Back propagation neural network (BPNN) has been proven to be a superior predictive tool when compared with MVRA.

  17. Medium-intensity acute exhaustive exercise induces neural cell apoptosis in the rat hippocampus

    Institute of Scientific and Technical Information of China (English)

    Shanni Li; Jin Liu; Hengmei Yan

    2013-01-01

    The present study assessed the influence of medium-intensity (treadmill at a speed of 19.3 m/min until exhaustion) and high-intensity (treadmill at a speed of 26.8 m/min until exhaustion) acute exhaustive exercise on rat hippocampal neural cell apoptosis. TUNEL staining showed significantly increased neural cell apoptosis in the hippocampal CA1 region of rats after medium- and high-intensity acute exhaustive exercise, particularly the medium-intensity acute exhaustive exercise, when compared with the control. Immunohistochemistry showed significantly increased expression of the antiapoptotic protein Bcl-2 and the proapoptotic protein Bax in the hippocampal CA1 region of rats after medium- and high-intensity acute exhaustive exercise. Additionally, the ratio of Bax to Bcl-2 increased in both exercise groups. In particular, the medium-intensity acute exhaustive exercise group had significantly higher Bax and Bcl-2 protein expression and a higher Bax/Bcl-2 ratio. These findings indicate that acute exhaustive exercise of different intensities can induce neural cell apoptosis in the hippocampus, and that medium-intensity acute exhaustive exercise results in greater damage when compared with high-intensity exercise.

  18. Mindful attention reduces neural and self-reported cue-induced craving in smokers

    OpenAIRE

    Westbrook, Cecilia; Creswell, John David; Tabibnia, Golnaz; Julson, Erica; Kober, Hedy; Tindle, Hilary A.

    2011-01-01

    An emerging body of research suggests that mindfulness-based interventions may be beneficial for smoking cessation and the treatment of other addictive disorders. One way that mindfulness may facilitate smoking cessation is through the reduction of craving to smoking cues. The present work considers whether mindful attention can reduce self-reported and neural markers of cue-induced craving in treatment seeking smokers. Forty-seven (n = 47) meditation-naïve treatment-seeking smokers (12-h abs...

  19. Covalent growth factor tethering to direct neural stem cell differentiation and self-organization.

    Science.gov (United States)

    Ham, Trevor R; Farrag, Mahmoud; Leipzig, Nic D

    2017-04-15

    Tethered growth factors offer exciting new possibilities for guiding stem cell behavior. However, many of the current methods present substantial drawbacks which can limit their application and confound results. In this work, we developed a new method for the site-specific covalent immobilization of azide-tagged growth factors and investigated its utility in a model system for guiding neural stem cell (NSC) behavior. An engineered interferon-γ (IFN-γ) fusion protein was tagged with an N-terminal azide group, and immobilized to two different dibenzocyclooctyne-functionalized biomimetic polysaccharides (chitosan and hyaluronan). We successfully immobilized azide-tagged IFN-γ under a wide variety of reaction conditions, both in solution and to bulk hydrogels. To understand the interplay between surface chemistry and protein immobilization, we cultured primary rat NSCs on both materials and showed pronounced biological effects. Expectedly, immobilized IFN-γ increased neuronal differentiation on both materials. Expression of other lineage markers varied depending on the material, suggesting that the interplay of surface chemistry and protein immobilization plays a large role in nuanced cell behavior. We also investigated the bioactivity of immobilized IFN-γ in a 3D environment in vivo and found that it sparked the robust formation of neural tube-like structures from encapsulated NSCs. These findings support a wide range of potential uses for this approach and provide further evidence that adult NSCs are capable of self-organization when exposed to the proper microenvironment. For stem cells to be used effectively in regenerative medicine applications, they must be provided with the appropriate cues and microenvironment so that they integrate with existing tissue. This study explores a new method for guiding stem cell behavior: covalent growth factor tethering. We found that adding an N-terminal azide-tag to interferon-γ enabled stable and robust Cu-free 'click

  20. Regulation of neural gene transcription by optogenetic inhibition of the RE1-silencing transcription factor.

    Science.gov (United States)

    Paonessa, Francesco; Criscuolo, Stefania; Sacchetti, Silvio; Amoroso, Davide; Scarongella, Helena; Pecoraro Bisogni, Federico; Carminati, Emanuele; Pruzzo, Giacomo; Maragliano, Luca; Cesca, Fabrizia; Benfenati, Fabio

    2016-01-01

    Optogenetics provides new ways to activate gene transcription; however, no attempts have been made as yet to modulate mammalian transcription factors. We report the light-mediated regulation of the repressor element 1 (RE1)-silencing transcription factor (REST), a master regulator of neural genes. To tune REST activity, we selected two protein domains that impair REST-DNA binding or recruitment of the cofactor mSin3a. Computational modeling guided the fusion of the inhibitory domains to the light-sensitive Avena sativa light-oxygen-voltage-sensing (LOV) 2-phototrophin 1 (AsLOV2). By expressing AsLOV2 chimeras in Neuro2a cells, we achieved light-dependent modulation of REST target genes that was associated with an improved neural differentiation. In primary neurons, light-mediated REST inhibition increased Na(+)-channel 1.2 and brain-derived neurotrophic factor transcription and boosted Na(+) currents and neuronal firing. This optogenetic approach allows the coordinated expression of a cluster of genes impinging on neuronal activity, providing a tool for studying neuronal physiology and correcting gene expression changes taking place in brain diseases.

  1. CSPG is a secreted factor that stimulates neural stem cell survival possibly by enhanced EGFR signaling.

    Directory of Open Access Journals (Sweden)

    Muly Tham

    Full Text Available Understanding how autocrine/paracrine factors regulate neural stem cell (NSC survival and growth is fundamental to the utilization of these cells for therapeutic applications and as cellular models for the brain. In vitro, NSCs can be propagated along with neural progenitors (NPs as neurospheres (nsphs. The nsph conditioned medium (nsph-CM contains cell-secreted factors that can regulate NSC behavior. However, the identity and exact function of these factors within the nsph-CM has remained elusive. We analyzed the nsph-CM by mass spectrometry and identified DSD-1-proteoglycan, a chondroitin sulfate proteoglycan (CSPG, apolipoprotein E (ApoE and cystatin C as components of the nsph-CM. Using clonal assays we show that CSPG and ApoE are responsible for the ability of the nsph-CM to stimulate nsph formation whereas cystatin C is not involved. Clonal nsphs generated in the presence of CSPG show more than four-fold increase in NSCs. Thus CSPG specifically enhances the survival of NSCs. CSPG also stimulates the survival of embryonic stem cell (ESC-derived NSCs, and thus may be involved in the developmental transition of ESCs to NSCs. In addition to its role in NSC survival, CSPG maintains the three dimensional structure of nsphs. Lastly, CSPG's effects on NSC survival may be mediated by enhanced signaling via EGFR, JAK/STAT3 and PI3K/Akt pathways.

  2. Gene array analysis of neural crest cells identifies transcription factors necessary for direct conversion of embryonic fibroblasts into neural crest cells

    Directory of Open Access Journals (Sweden)

    Tsutomu Motohashi

    2016-03-01

    Full Text Available Neural crest cells (NC cells are multipotent cells that emerge from the edge of the neural folds and migrate throughout the developing embryo. Although the gene regulatory network for generation of NC cells has been elucidated in detail, it has not been revealed which of the factors in the network are pivotal to directing NC identity. In this study we analyzed the gene expression profile of a pure NC subpopulation isolated from Sox10-IRES-Venus mice and investigated whether these genes played a key role in the direct conversion of Sox10-IRES-Venus mouse embryonic fibroblasts (MEFs into NC cells. The comparative molecular profiles of NC cells and neural tube cells in 9.5-day embryos revealed genes including transcription factors selectively expressed in developing trunk NC cells. Among 25 NC cell-specific transcription factor genes tested, SOX10 and SOX9 were capable of converting MEFs into SOX10-positive (SOX10+ cells. The SOX10+ cells were then shown to differentiate into neurons, glial cells, smooth muscle cells, adipocytes and osteoblasts. These SOX10+ cells also showed limited self-renewal ability, suggesting that SOX10 and SOX9 directly converted MEFs into NC cells. Conversely, the remaining transcription factors, including well-known NC cell specifiers, were unable to convert MEFs into SOX10+ NC cells. These results suggest that SOX10 and SOX9 are the key factors necessary for the direct conversion of MEFs into NC cells.

  3. The fibroblast growth factor receptor (FGFR) agonist FGF1 and the neural cell adhesion molecule-derived peptide FGL activate FGFR substrate 2alpha differently

    DEFF Research Database (Denmark)

    Chen, Yongshuo; Li, Shizhong; Berezin, Vladimir

    2010-01-01

    Activation of fibroblast growth factor (FGF) receptors (FGFRs) both by FGFs and by the neural cell adhesion molecule (NCAM) is crucial in the development and function of the nervous system. We found that FGFR substrate 2alpha (FRS2alpha), Src homologous and collagen A (ShcA), and phospholipase......-Cgamma (PLCgamma) were all required for neurite outgrowth from cerebellar granule neurons (CGNs) induced by FGF1 and FGL (an NCAM-derived peptide agonist of FGFR1). Like FGF1, FGL induced tyrosine phosphorylation of FGFR1, FRS2alpha, ShcA, and PLCgamma in a time- and dose-dependent manner. However, the activation...... of FRS2alpha by FGL was significantly lower than the activation by FGF1, indicating a differential signaling profile induced by NCAM compared with the cognate growth factor....

  4. Physics instruction induces changes in neural knowledge representation during successive stages of learning.

    Science.gov (United States)

    Mason, Robert A; Just, Marcel Adam

    2015-05-01

    Incremental instruction on the workings of a set of mechanical systems induced a progression of changes in the neural representations of the systems. The neural representations of four mechanical systems were assessed before, during, and after three phases of incremental instruction (which first provided information about the system components, then provided partial causal information, and finally provided full functional information). In 14 participants, the neural representations of four systems (a bathroom scale, a fire extinguisher, an automobile braking system, and a trumpet) were assessed using three recently developed techniques: (1) machine learning and classification of multi-voxel patterns; (2) localization of consistently responding voxels; and (3) representational similarity analysis (RSA). The neural representations of the systems progressed through four stages, or states, involving spatially and temporally distinct multi-voxel patterns: (1) initially, the representation was primarily visual (occipital cortex); (2) it subsequently included a large parietal component; (3) it eventually became cortically diverse (frontal, parietal, temporal, and medial frontal regions); and (4) at the end, it demonstrated a strong frontal cortex weighting (frontal and motor regions). At each stage of knowledge, it was possible for a classifier to identify which one of four mechanical systems a participant was thinking about, based on their brain activation patterns. The progression of representational states was suggestive of progressive stages of learning: (1) encoding information from the display; (2) mental animation, possibly involving imagining the components moving; (3) generating causal hypotheses associated with mental animation; and finally (4) determining how a person (probably oneself) would interact with the system. This interpretation yields an initial, cortically-grounded, theory of learning of physical systems that potentially can be related to cognitive

  5. Risk factors for amiodarone-induced thyroid dysfunction in Japan

    Directory of Open Access Journals (Sweden)

    Sayoko Kinoshita

    2016-12-01

    Conclusion: DCM and cardiac sarcoidosis were identified as risk factors for amiodarone-induced hyperthyroidism. Risk factors for amiodarone-induced hypothyroidism included higher baseline TSH level and lower baseline free T4 level, suggesting that subclinical hypothyroidism may be a potential risk factor for the development of amiodarone-induced hypothyroidism.

  6. Cross-talk between the epidermal growth factor-like repeats/fibronectin 6-8 repeats domains of Tenascin-R and microglia modulates neural stem/progenitor cell proliferation and differentiation.

    Science.gov (United States)

    Liao, Hong; Huang, Wenhui; Niu, Rui; Sun, Lixin; Zhang, Luyong

    2008-01-01

    Mounting evidence has demonstrated that the microenvironment of stem/progenitor cells plays an important role in their proliferation and commitment to their fate. However, it remains unclear how all elements, such as astrocytes, microglia, extracellular matrix molecules, soluble factors, and their cross-talk interactions in the microenvironments, affect neural stem/progenitor cell fate. This work explored the influences of cross-talk between Tenascin-R (TN-R) and microglia on neural stem/progenitor cell proliferation and differentiation. Our results show that microglia triggered by TN-R distinct domains EGF-like repeats (EGFL) and fibronectin 6-8 repeats (FN6-8) significantly enhanced the proliferation of neural stem/progenitor cells and also obviously induced the differentiation into neurons but not oligodendrocytes. Neurite processes of neurons generated from neural progenitor cells were promoted by both EGFL and FN6-8 domains-activated microglia. Microglia triggered by EGFL and FN6-8 secreted brain-derived neurotrophic factor (BDNF) and transforming growth factor-beta (TGF-beta); interestingly, FN6-8 could activate microglia to secrete nerve growth factor in addition to BDNF and TGF-beta, but EGFL domain could not. All these data implied that the cross-talk between TN-R distinct domains EGFL/FN6-8 and microglia promoted neural stem/progenitor cell proliferation and induced their differentiation into neurons.

  7. Orally administered melatonin prevents lipopolysaccharide-induced neural tube defects in mice.

    Directory of Open Access Journals (Sweden)

    Lin Fu

    Full Text Available Lipopolysaccharide (LPS has been associated with adverse pregnant outcomes, including fetal demise, intra-uterine growth restriction (IUGR, neural tube defects (NTDs and preterm delivery in rodent animals. Previous studies demonstrated that melatonin protected against LPS-induced fetal demise, IUGR and preterm delivery. The aim of the present study was to investigate the effects of melatonin on LPS-induced NTDs. All pregnant mice except controls were intraperitoneally injected with LPS (25 µg/kg daily from gestational day (GD8 to GD12. Some pregnant mice were orally administered with melatonin (MT, 50 mg/kg before each LPS injection. A five-day LPS injection resulted in 27.5% of fetuses with anencephaly, exencephaly or encephalomeningocele. Additional experiment showed that maternal LPS exposure significantly down-regulated placental proton-coupled folate transporter (pcft and disturbed folate transport from maternal circulation through the placentas into the fetus. Interestingly, melatonin significantly attenuated LPS-induced down-regulation of placental pcft. Moreover, melatonin markedly improved the transport of folate from maternal circulation through the placentas into the fetus. Correspondingly, orally administered melatonin reduced the incidence of LPS-induced anencephaly, exencephaly or encephalomeningocele. Taken together, these results suggest that orally administered melatonin prevents LPS-induced NTDs through alleviating LPS-induced disturbance of folate transport from maternal circulation through the placenta into the fetus.

  8. Herpes simplex virus induces neural oxidative damage via microglial cell Toll-like receptor-2

    Directory of Open Access Journals (Sweden)

    Little Morgan R

    2010-06-01

    Full Text Available Abstract Background Using a murine model of herpes simplex virus (HSV-1 encephalitis, our laboratory has determined that induction of proinflammatory mediators in response to viral infection is largely mediated through a Toll-like receptor-2 (TLR2-dependent mechanism. Published studies have shown that, like other inflammatory mediators, reactive oxygen species (ROS are generated during viral brain infection. It is increasingly clear that ROS are responsible for facilitating secondary tissue damage during central nervous system infection and may contribute to neurotoxicity associated with herpes encephalitis. Methods Purified microglial cell and mixed neural cell cultures were prepared from C57B/6 and TLR2-/- mice. Intracellular ROS production in cultured murine microglia was measured via 2', 7'-Dichlorofluorescin diacetate (DCFH-DA oxidation. An assay for 8-isoprostane, a marker of lipid peroxidation, was utilized to measure free radical-associated cellular damage. Mixed neural cultures obtained from β-actin promoter-luciferase transgenic mice were used to detect neurotoxicity induced by HSV-infected microglia. Results Stimulation with HSV-1 elevated intracellular ROS in wild-type microglial cell cultures, while TLR2-/- microglia displayed delayed and attenuated ROS production following viral infection. HSV-infected TLR2-/- microglia produced less neuronal oxidative damage to mixed neural cell cultures in comparison to HSV-infected wild-type microglia. Further, HSV-infected TLR2-/- microglia were found to be less cytotoxic to cultured neurons compared to HSV-infected wild-type microglia. These effects were associated with decreased activation of p38 MAPK and p42/p44 ERK in TLR2-/- mice. Conclusions These studies demonstrate the importance of microglial cell TLR2 in inducing oxidative stress and neuronal damage in response to viral infection.

  9. Induced neural stem cells as a means of treatment in Huntington's disease.

    Science.gov (United States)

    Choi, Kyung-Ah; Hong, Sunghoi

    2017-08-09

    Huntington's disease (HD) is an inherited neurodegenerative disease characterized by chorea, dementia, and depression caused by progressive nerve cell degeneration, which is triggered by expanded CAG repeats in the huntingtin (Htt) gene. Currently, there is no cure for this disease, nor is there an effective medicine available to delay or improve the physical, mental, and behavioral severities caused by it. Areas covered: In this review, the authors describe the use of induced neural stem cells (iNSCs) by direct conversion technology, which offers great advantages as a therapeutic cell type to treat HD. Expert opinion: Cell conversion of somatic cells into a desired stem cell type is one of the most promising treatments for HD because it could be facilitated for the generation of patient-specific neural stem cells. The induced pluripotent stem cells (iPSCs) have a powerful potential for differentiation into neurons, but they may cause teratoma formation due to an undifferentiated pluripotent stem cell after transplantation Therefore, direct conversion of somatic cells into iNSCs is a promising alternative technology in regenerative medicine and the iNSCs may be provided as a therapeutic cell source for Huntington's disease.

  10. Organization of anti-phase synchronization pattern in neural networks: what are the key factors?

    Directory of Open Access Journals (Sweden)

    Dong eLi

    2011-12-01

    Full Text Available Anti-phase oscillation has been widely observed in cortical neuralnetwork. Elucidating the mechanism underlying the organization ofanti-phase pattern is of significance for better understanding morecomplicated pattern formations in brain networks. In dynamicalsystems theory, the organization of anti-phase oscillation patternhas usually been considered to relate to time-delay in coupling.This is consistent to conduction delays in real neural networks inthe brain due to finite propagation velocity of action potentials.However, other structural factors in cortical neural network, suchas modular organization (connection density and the coupling types(excitatory or inhibitory, could also play an important role. Inthis work, we investigate the anti-phase oscillation patternorganized on a two-module network of either neuronal cell model orneural mass model, and analyze the impact of the conduction delaytimes, the connection densities, and coupling types. Our resultsshow that delay times and coupling types can play key roles in thisorganization. The connection densities may have an influence on thestability if an anti-phase pattern exists due to the other factors.Furthermore, we show that anti-phase synchronization of slowoscillations can be achieved with small delay times if there isinteraction between slow and fast oscillations. These results aresignificant for further understanding more realistic spatiotemporaldynamics of cortico-cortical communications.

  11. Effects of aripiprazole on caffeine-induced hyperlocomotion and neural activation in the striatum.

    Science.gov (United States)

    Batista, Luara A; Viana, Thércia G; Silveira, Vívian T; Aguiar, Daniele C; Moreira, Fabrício A

    2016-01-01

    Aripiprazole is an antipsychotic that acts as a partial agonist at dopamine D2 receptors. In addition to its antipsychotic activity, this compound blocks the effects of some psychostimulant drugs. It has not been verified, however, if aripiprazole interferes with the effects of caffeine. Hence, this study tested the hypothesis that aripiprazole prevents caffeine-induced hyperlocomotion and investigated the effects of these drugs on neural activity in the striatum. Male Swiss mice received injections of vehicle or antipsychotic drugs followed by vehicle or caffeine. Locomotion was analyzed in a circular arena and c-Fos protein expression was quantified in the dorsolateral, dorsomedial, and ventrolateral striatum, and in the core and shell regions of nucleus accumbens. Aripiprazole (0.1, 1, and 10 mg/kg) prevented caffeine (10 mg/kg)-induced hyperlocomotion at doses that do not change basal locomotion. Haloperidol (0.01, 0.03, and 0.1 mg/kg) also decreased caffeine-induced hyperlocomotion at all doses, although at the two higher doses, this compound reduced basal locomotion. Immunohistochemistry analysis showed that aripiprazole increases c-Fos protein expression in all regions studied, whereas caffeine did not alter c-Fos protein expression. Combined treatment of aripiprazole and caffeine resulted in a decrease in the number of c-Fos positive cells as compared to the group receiving aripiprazole alone. In conclusion, aripiprazole prevents caffeine-induced hyperlocomotion and increases neural activation in the striatum. This latter effect is reduced by subsequent administration of caffeine. These results advance our understanding on the pharmacological profile of aripiprazole.

  12. Neural cell adhesion molecule differentially interacts with isoforms of the fibroblast growth factor receptor.

    Science.gov (United States)

    Christensen, Claus; Berezin, Vladimir; Bock, Elisabeth

    2011-10-26

    The fibroblast growth factor receptor (FGFR) can be activated through direct interactions with various fibroblast growth factors or through a number of cell adhesion molecules, including the neural cell adhesion molecule (NCAM). We produced recombinant proteins comprising the ligand-binding immunoglobulin-like modules 2 and 3 of FGFR1b, FGFR1c, FGFR2b, FGFR2c, FGFR3b, FGFR3c, and FGFR4, and found that all FGFR isoforms, except for FGFR4, interacted with NCAM. The binding affinity of NCAM-FGFR interactions was considerably higher for splice variant 'b' than for splice variant 'c'. We suggest that the expression pattern of various FGFR isoforms determines the cell context-specific effects of NCAM signaling through FGFR.

  13. Notch Sensitivity Factor Determination With Artificial Neural Network For Shafts Under The Bending Stress

    Directory of Open Access Journals (Sweden)

    Murat Tolga Özkan

    2013-01-01

    Full Text Available Notch, hole, tap and a variety of geometric shapes such as curves or discontinuities can be found with various reasons in the design of Machine Element. Stress is caused by sudden changes in section aggregating. Stress concentration can occur with the reason of material features of size or direction of forces application. This type of stress concentration in the material brings out the effect of notch. Notch impact can lead to distortions and breakage of materials. In this study, the notch sensitivity factor values have been modelled Artificial Neural Networks (ANN for shafts that is under the influence of bending stress, and the accuracy of the model has been verified by using Statistica software. The model has been developed using Pythia. With this software, the user can be obtained the accurate value by inputing shaft dimension and the applied force without the need for notch sensitivity factor tables and any calculations.

  14. Mechanisms for Interferon-α-Induced Depression and Neural Stem Cell Dysfunction

    Directory of Open Access Journals (Sweden)

    Lian-Shun Zheng

    2014-07-01

    Full Text Available New neurons generated by the neural stem cells (NSCs in the adult hippocampus play an important role in emotional regulation and respond to the action of antidepressants. Depression is a common and serious side effect of interferon-α (IFN-α, which limits its use as an antiviral and antitumor drug. However, the mechanism(s underlying IFN-induced depression are largely unknown. Using a comprehensive battery of behavioral tests, we found that mice subjected to IFN-α treatment exhibited a depression-like phenotype. IFN-α directly suppressed NSC proliferation, resulting in the reduced generation of new neurons. Brain-specific mouse knockout of the IFN-α receptor prevented IFN-α-induced depressive behavioral phenotypes and the inhibition of neurogenesis, suggesting that IFN-α suppresses hippocampal neurogenesis and induces depression via its receptor in the brain. These findings provide insight for understanding the neuropathology underlying IFN-α-induced depression and for developing new strategies for the prevention and treatment of IFN-α-induced depressive effects.

  15. Identification and dissection of a key enhancer mediating cranial neural crest specific expression of transcription factor, Ets-1.

    Science.gov (United States)

    Barembaum, Meyer; Bronner, Marianne E

    2013-10-15

    Neural crest cells form diverse derivatives that vary according to their level of origin along the body axis, with only cranial neural crest cells contributing to facial skeleton. Interestingly, the transcription factor Ets-1 is uniquely expressed in cranial but not trunk neural crest, where it functions as a direct input into neural crest specifier genes, Sox10 and FoxD3. We have isolated and interrogated a cis-regulatory element, conserved between birds and mammals, that drives reporter expression in a manner that recapitulates that of endogenous Ets-1 expression in the neural crest. Within a minimal Ets-1 enhancer region, mutation of putative binding sites for SoxE, homeobox, Ets, TFAP2 or Fox proteins results in loss or reduction of neural crest enhancer activity. Morpholino-mediated loss-of-function experiments show that Sox9, Pax7, Msx1/2, Ets-1, TFAP2A and FoxD3, all are required for enhancer activity. In contrast, mutation of a putative cMyc/E-box sequence augments reporter expression, consistent with this being a repressor binding site. Taken together, these results uncover new inputs into Ets-1, revealing critical links in the cranial neural crest gene regulatory network. © 2013 Elsevier Inc. All rights reserved.

  16. Selective neuronal differentiation of neural stem cells induced by nanosecond microplasma agitation

    Directory of Open Access Journals (Sweden)

    Z. Xiong

    2014-03-01

    Full Text Available An essential step for therapeutic and research applications of stem cells is their ability to differentiate into specific cell types. Neuronal cells are of great interest for medical treatment of neurodegenerative diseases and traumatic injuries of central nervous system (CNS, but efforts to produce these cells have been met with only modest success. In an attempt of finding new approaches, atmospheric-pressure room-temperature microplasma jets (MPJs are shown to effectively direct in vitro differentiation of neural stem cells (NSCs predominantly into neuronal lineage. Murine neural stem cells (C17.2-NSCs treated with MPJs exhibit rapid proliferation and differentiation with longer neurites and cell bodies eventually forming neuronal networks. MPJs regulate ~75% of NSCs to differentiate into neurons, which is a higher efficiency compared to common protein- and growth factors-based differentiation. NSCs exposure to quantized and transient (~150 ns micro-plasma bullets up-regulates expression of different cell lineage markers as β-Tubulin III (for neurons and O4 (for oligodendrocytes, while the expression of GFAP (for astrocytes remains unchanged, as evidenced by quantitative PCR, immunofluorescence microscopy and Western Blot assay. It is shown that the plasma-increased nitric oxide (NO production is a factor in the fate choice and differentiation of NSCs followed by axonal growth. The differentiated NSC cells matured and produced mostly cholinergic and motor neuronal progeny. It is also demonstrated that exposure of primary rat NSCs to the microplasma leads to quite similar differentiation effects. This suggests that the observed effect may potentially be generic and applicable to other types of neural progenitor cells. The application of this new in vitro strategy to selectively differentiate NSCs into neurons represents a step towards reproducible and efficient production of the desired NSC derivatives.

  17. Syndromes, Disorders and Maternal Risk Factors Associated With Neural Tube Defects (VII

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2008-09-01

    Full Text Available Neural tube defects (NTDs may be associated with syndromes, disorders and maternal risk factors. This article provides a comprehensive review of the syndromes, disorders and maternal risk factors associated with NTDs, including DK phocomelia syndrome (von Voss-Cherstvoy syndrome, Siegel-Bartlet syndrome, fetal warfarin syndrome, craniotelencephalic dysplasia, Czeizel-Losonci syndrome, maternal cocaine abuse, Weissenbacher-Zweymüller syndrome, parietal foramina (cranium bifidum, Apert syndrome, craniomicromelic syndrome, XX-agonadism with multiple dysraphic lesions including omphalocele and NTDs, Fryns microphthalmia syndrome, Gershoni-Baruch syndrome, PHAVER syndrome, periconceptional vitamin B6 deficiency, and autosomal dominant Dandy-Walker malformation with occipital cephalocele. NTDs associated with these syndromes, disorders and maternal risk factors are a rare but important cause of NTDs. The recurrence risk and the preventive effect of maternal folic acid intake in NTDs associated with syndromes, disorders and maternal risk factors may be different from those of nonsyndromic multifactorial NTDs. Perinatal diagnosis of NTDs should alert doctors to the syndromes, disorders and maternal risk factors associated with NTDs, and prompt thorough etiologic investigation and genetic counseling.

  18. Syndromes, Disorders and Maternal Risk Factors Associated with Neural Tube Defects (III

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2008-06-01

    Full Text Available Fetuses with neural tube defects (NTDs may be associated with syndromes, disorders, and maternal and fetal risk factors. This article provides a comprehensive review of syndromes, disorders, and maternal and fetal risk factors associated with NTDs, such as omphalocele, OEIS (omphalocele-exstrophy-imperforate anus-spinal defects complex, pentalogy of Cantrell, amniotic band sequence, limb-body wall complex, Meckel syndrome, Joubert syndrome, skeletal dysplasia, diabetic embryopathy, and single nucleotide polymorphisms in genes of glucose metabolism. NTDs associated with syndromes, disorders, and maternal and fetal risk factors are a rare but important cause of NTDs. The recurrence risk and the preventive effect of maternal folic acid intake in NTDs associated with syndromes, disorders and maternal risk factors may be different from those of nonsyndromic multi facto rial NTDs. Perinatal identification of NTDs should alert the clinician to the syndromes, disorders, and maternal and fetal risk factors associated with NTDs, and prompt a thorough etiologic investigation and genetic counseling. [Taiwan J Obstet Cynecol 2008;47(2:131-140

  19. Neural Correlates of Sevoflurane-induced Unconsciousness Identified by Simultaneous Functional Magnetic Resonance Imaging and Electroencephalography.

    Science.gov (United States)

    Ranft, Andreas; Golkowski, Daniel; Kiel, Tobias; Riedl, Valentin; Kohl, Philipp; Rohrer, Guido; Pientka, Joachim; Berger, Sebastian; Thul, Alexander; Maurer, Max; Preibisch, Christine; Zimmer, Claus; Mashour, George A; Kochs, Eberhard F; Jordan, Denis; Ilg, Rüdiger

    2016-11-01

    The neural correlates of anesthetic-induced unconsciousness have yet to be fully elucidated. Sedative and anesthetic states induced by propofol have been studied extensively, consistently revealing a decrease of frontoparietal and thalamocortical connectivity. There is, however, less understanding of the effects of halogenated ethers on functional brain networks. The authors recorded simultaneous resting-state functional magnetic resonance imaging and electroencephalography in 16 artificially ventilated volunteers during sevoflurane anesthesia at burst suppression and 3 and 2 vol% steady-state concentrations for 700 s each to assess functional connectivity changes compared to wakefulness. Electroencephalographic data were analyzed using symbolic transfer entropy (surrogate of information transfer) and permutation entropy (surrogate of cortical information processing). Functional magnetic resonance imaging data were analyzed by an independent component analysis and a region-of-interest-based analysis. Electroencephalographic analysis showed a significant reduction of anterior-to-posterior symbolic transfer entropy and global permutation entropy. At 2 vol% sevoflurane concentrations, frontal and thalamic networks identified by independent component analysis showed significantly reduced within-network connectivity. Primary sensory networks did not show a significant change. At burst suppression, all cortical networks showed significantly reduced functional connectivity. Region-of-interest-based thalamic connectivity at 2 vol% was significantly reduced to frontoparietal and posterior cingulate cortices but not to sensory areas. Sevoflurane decreased frontal and thalamocortical connectivity. The changes in blood oxygenation level dependent connectivity were consistent with reduced anterior-to-posterior directed connectivity and reduced cortical information processing. These data advance the understanding of sevoflurane-induced unconsciousness and contribute to a

  20. Longterm effects of cardiac mediastinal nerve cryoablation on neural inducibility of atrial fibrillation in canines.

    Science.gov (United States)

    Leiria, Tiago Luiz Luz; Glavinovic, Tamara; Armour, J Andrew; Cardinal, René; de Lima, Gustavo Glotz; Kus, Teresa

    2011-04-26

    In canines, excessive activation of select mediastinal nerve inputs to the intrinsic cardiac nervous system induces atrial fibrillation (AF). Since ablation of neural elements is proposed as an adjunct to circumferential pulmonary vein ablation for AF, we investigated the short and long-term effects of mediastinal nerve ablation on AF inducibility. Under general anesthesia, in 11 dogs several mediastinal nerve sites were identified on the superior vena cava that, when stimulated electrically during the atrial refractory period, reproducibly initiated AF. Cryoablation of one nerve site was then performed and inducibility retested early (1-2 months post Cryo; n=7) or late (4 months post Cryo; n=4). Four additional dogs that underwent a sham procedure were retested 1 to 2 months post-surgery. Stimulation induced AF at 91% of nerve sites tested in control versus 21% nerve sites early and 54% late post-ablation (both P<0.05). Fewer stimuli were required to induce AF in controls versus the Early Cryo group; this capacity returned to normal values in the Late Cryo group. AF episodes were longer in control versus the Early or Late Cryo groups. Heart rate responses to vagal or stellate ganglion stimulation, as well as to local nicotine infusion into the right coronary artery, were similar in all groups. In conclusion, focal damage to intrinsic cardiac neuronal inputs causes short-term stunning of neuronal inducibility of AF without major loss of overall adrenergic or cholinergic efferent neuronal control. That recovery of AF inducibility occurs rapidly post-surgery indicates the plasticity of intrathoracic neuronal elements to focal injury. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Integrating a Storage Factor into R-NARX Neural Networks for Flood Forecasts

    Science.gov (United States)

    Chou, Po-Kai; Chang, Li-Chiu; Chang, Fi-John; Shih, Ban-Jwu

    2017-04-01

    Because mountainous terrains and steep landforms rapidly accelerate the speed of flood flow in Taiwan island, accurate multi-step-ahead inflow forecasts during typhoon events for providing reliable information benefiting the decision-makings of reservoir pre-storm release and flood-control operation are considered crucial and challenging. Various types of artificial neural networks (ANNs) have been successfully applied in hydrological fields. This study proposes a recurrent configuration of the nonlinear autoregressive with exogenous inputs (NARX) network, called R-NARX, with various effective inputs to forecast the inflows of the Feitsui Reservoir, a pivot reservoir for water supply to Taipei metropolitan in Taiwan, during typhoon periods. The proposed R-NARX is constructed based on the recurrent neural network (RNN), which is commonly used for modelling nonlinear dynamical systems. A large number of hourly rainfall and inflow data sets collected from 95 historical typhoon events in the last thirty years are used to train, validate and test the models. The potential input variables, including rainfall in previous time steps (one to six hours), cumulative rainfall, the storage factor and the storage function, are assessed, and various models are constructed with their reliability and accuracy being tested. We find that the previous (t-2) rainfall and cumulative rainfall are crucial inputs and the storage factor and the storage function would also improve the forecast accuracy of the models. We demonstrate that the R-NARX model not only can accurately forecast the inflows but also effectively catch the peak flow without adopting observed inflow data during the entire typhoon period. Besides, the model with the storage factor is superior to the model with the storage function, where its improvement can reach 24%. This approach can well model the rainfall-runoff process for the entire flood forecasting period without the use of observed inflow data and can provide

  2. The Factors that Induce or Overcome Freezing of Gait in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    S. Rahman

    2008-01-01

    Full Text Available Freezing of gait (FoG, a transient halt in walking, is a major mobility problem for patients with Parkinson’s disease (PD. This study examined the factors that induce FoG, and identified the cues and strategies that help overcome it through a postal survey of 130 PD patients. 72% reported FoG. The factors that commonly induced FoG were turning, fatigue, confined spaces and stressful situations, in addition to emotional factors. FoG was also ameliorated by various attentional and external cueing strategies. The concept of paradoxical kinesis, the potential neural substrates of such external cueing effects, and their importance for rehabilitation in PD are discussed.

  3. Salicylate induced tinnitus: behavioral measures and neural activity in auditory cortex of awake rats.

    Science.gov (United States)

    Yang, Guang; Lobarinas, Edward; Zhang, Liyan; Turner, Jeremy; Stolzberg, Daniel; Salvi, Richard; Sun, Wei

    2007-04-01

    Neurophysiological studies of salicylate-induced tinnitus have generally been carried out under anesthesia, a condition that abolishes the perception of tinnitus and depresses neural activity. To overcome these limitations, measurement of salicylate induced tinnitus were obtained from rats using schedule induced polydipsia avoidance conditioning (SIPAC) and gap pre-pulse inhibition of acoustic startle (GPIAS). Both behavioral measures indicated that tinnitus was present after treatment with 150 and 250 mg/kg of salicylate; measurements with GPIAS indicated that the pitch of the tinnitus was near 16 kHz. Chronically implanted microwire electrode arrays were used to monitor the local field potentials and spontaneous discharge rate from multiunit clusters in the auditory cortex of awake rats before and after treatment with 150 mg/kg of salicylate. The amplitude of the local field potential elicited with 60 dB SPL tone bursts increased significantly 2h after salicylate treatment particularly at 16-20 kHz; frequencies associated with the tinnitus pitch. Field potential amplitudes had largely recovered 1-2 days post-salicylate when behavioral results showed that tinnitus was absent. The mean spontaneous spike recorded from the same multiunit cluster pre- and post-salicylate decreased from 22 spikes/s before treatment to 14 spikes/s 2h post-salicylate and recovered 1 day post-treatment. These preliminary physiology data suggest that salicylate induced tinnitus is associated with sound evoked hyperactivity in auditory cortex and spontaneous hypoactivity.

  4. Differentiation of Human Bone Marrow Stromal Cells into Neural-Like Cells Induced by Sodium Ferulate in vitro

    Institute of Scientific and Technical Information of China (English)

    Yang Wang; Zhifeng Deng; Xianliang Lai; Wei Tu

    2005-01-01

    Human marrow stromal cells (hMSCs) are multipotential stem cells, capable of differentiating into bone, cartilage,fat and muscle. Several recent reports demonstrated that hMSCs have been also differentiated into neural cells.However, only a few reported inducers are applicable for clinical use. This work is to explore the effects of sodium ferulate (SF) on differentiation of hMSCs into neural cells in vitro. We found that hMSCs could be induced to the cells with typical neural morphology when cultured with SF. The cells express neural proteins, such as nestin,neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP). About 30% of the hMSC-derived cells expressed nestin when cultured with SF for 3 h, but no expression was detected after 24 h. The percentages of positive cells for NSE or GFAP were about 67% and 39% separately at 6 h, and reached the plateau phage after treatment with SF for 3 days. The data suggest that SF can induce hMSCs to differentiate into neural-like cells in vitro.

  5. A Novel Approach for Blast-Induced Flyrock Prediction Based on Imperialist Competitive Algorithm and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Aminaton Marto

    2014-01-01

    Full Text Available Flyrock is one of the major disturbances induced by blasting which may cause severe damage to nearby structures. This phenomenon has to be precisely predicted and subsequently controlled through the changing in the blast design to minimize potential risk of blasting. The scope of this study is to predict flyrock induced by blasting through a novel approach based on the combination of imperialist competitive algorithm (ICA and artificial neural network (ANN. For this purpose, the parameters of 113 blasting operations were accurately recorded and flyrock distances were measured for each operation. By applying the sensitivity analysis, maximum charge per delay and powder factor were determined as the most influential parameters on flyrock. In the light of this analysis, two new empirical predictors were developed to predict flyrock distance. For a comparison purpose, a predeveloped backpropagation (BP ANN was developed and the results were compared with those of the proposed ICA-ANN model and empirical predictors. The results clearly showed the superiority of the proposed ICA-ANN model in comparison with the proposed BP-ANN model and empirical approaches.

  6. A novel approach for blast-induced flyrock prediction based on imperialist competitive algorithm and artificial neural network.

    Science.gov (United States)

    Marto, Aminaton; Hajihassani, Mohsen; Armaghani, Danial Jahed; Mohamad, Edy Tonnizam; Makhtar, Ahmad Mahir

    2014-01-01

    Flyrock is one of the major disturbances induced by blasting which may cause severe damage to nearby structures. This phenomenon has to be precisely predicted and subsequently controlled through the changing in the blast design to minimize potential risk of blasting. The scope of this study is to predict flyrock induced by blasting through a novel approach based on the combination of imperialist competitive algorithm (ICA) and artificial neural network (ANN). For this purpose, the parameters of 113 blasting operations were accurately recorded and flyrock distances were measured for each operation. By applying the sensitivity analysis, maximum charge per delay and powder factor were determined as the most influential parameters on flyrock. In the light of this analysis, two new empirical predictors were developed to predict flyrock distance. For a comparison purpose, a predeveloped backpropagation (BP) ANN was developed and the results were compared with those of the proposed ICA-ANN model and empirical predictors. The results clearly showed the superiority of the proposed ICA-ANN model in comparison with the proposed BP-ANN model and empirical approaches.

  7. Gallium nitride induces neuronal differentiation markers in neural stem/precursor cells derived from rat cerebral cortex.

    Science.gov (United States)

    Chen, Chi-Ruei; Li, Yi-Chen; Young, Tai-Horng

    2009-09-01

    In the present study, gallium nitride (GaN) was used as a substrate to culture neural stem/precursor cells (NSPCs), isolated from embryonic rat cerebral cortex, to examine the effect of GaN on the behavior of NSPCs in the presence of basic fibroblast growth factor (bFGF) in serum-free medium. Morphological studies showed that neurospheres maintained their initial shape and formed many long and thick processes with the fasciculate feature on GaN. Immunocytochemical characterization showed that GaN could induce the differentiation of NSPCs into neurons and astrocytes. Compared to poly-d-lysine (PDL), the most common substrate used for culturing neurons, there was considerable expression of synapsin I for differentiated neurons on GaN, suggesting GaN could induce the differentiation of NSPCs towards the mature differentiated neurons. Western blot analysis showed that the suppression of glycogen synthase kinase-3beta (GSK-3beta) activity was one of the effects of GaN-promoted NSPC differentiation into neurons. Finally, compared to PDL, GaN could significantly improve cell survival to reduce cell death after long-term culture. These results suggest that GaN potentially has a combination of electric characteristics suitable for developing neuron and/or NSPC chip systems.

  8. Inducible expression of noggin selectively expands neural progenitors in the adult SVZ

    Directory of Open Access Journals (Sweden)

    M. Morell

    2015-01-01

    Full Text Available Multipotent, self-renewing stem cells are present throughout the developing nervous system remaining in discrete regions of the adult brain. In the subventricular zone (SVZ signaling molecules, including the bone morphogenetic proteins and their secreted inhibitor, noggin appear to play a critical role in controlling neural stem cell (NSC behavior. To examine the function of this signaling pathway in the intact nervous system, we developed a transgenic mouse model in which noggin expression can be induced specifically in NSC via a nestin-driven reverse tetracycline-controlled transactivator (rtTA. In adult animals, the induction of noggin expression promotes the proliferation of neural progenitors in the SVZ, and shifts the differentiation of B cells (NSC from mature astrocytes to transit amplifying C cells and oligodendrocyte precursor cells without depleting the NSC population. Noggin expression significantly increases neuronal and oligodendrocyte differentiation both in vivo and in vitro when NSCs are grown as neurospheres. These results demonstrate that noggin/BMP interactions tightly control cell fate in the SVZ.

  9. Neural substrates of human facial expression of pleasant emotion induced by comic films: a PET Study.

    Science.gov (United States)

    Iwase, Masao; Ouchi, Yasuomi; Okada, Hiroyuki; Yokoyama, Chihiro; Nobezawa, Shuji; Yoshikawa, Etsuji; Tsukada, Hideo; Takeda, Masaki; Yamashita, Ko; Takeda, Masatoshi; Yamaguti, Kouzi; Kuratsune, Hirohiko; Shimizu, Akira; Watanabe, Yasuyoshi

    2002-10-01

    Laughter or smile is one of the emotional expressions of pleasantness with characteristic contraction of the facial muscles, of which the neural substrate remains to be explored. This currently described study is the first to investigate the generation of human facial expression of pleasant emotion using positron emission tomography and H(2)(15)O. Regional cerebral blood flow (rCBF) during laughter/smile induced by visual comics and the magnitude of laughter/smile indicated significant correlation in the bilateral supplementary motor area (SMA) and left putamen (P < 0.05, corrected), but no correlation in the primary motor area (M1). In the voluntary facial movement, significant correlation between rCBF and the magnitude of EMG was found in the face area of bilateral M1 and the SMA (P < 0.001, uncorrected). Laughter/smile, as opposed to voluntary movement, activated the visual association areas, left anterior temporal cortex, left uncus, and orbitofrontal and medial prefrontal cortices (P < 0.05, corrected), whereas voluntary facial movement generated by mimicking a laughing/smiling face activated the face area of the left M1 and bilateral SMA, compared with laughter/smile (P < 0.05, corrected). We demonstrated distinct neural substrates of emotional and volitional facial expression and defined cognitive and experiential processes of a pleasant emotion, laughter/smile.

  10. Effects of vibratory stimulation-induced kinesthetic illusions on the neural activities of patients with stroke.

    Science.gov (United States)

    Kodama, Takayuki; Nakano, Hideki; Ohsugi, Hironori; Murata, Shin

    2016-01-01

    [Purpose] This study evaluated the influence of vibratory stimulation-induced kinesthetic illusion on brain function after stroke. [Subjects] Twelve healthy individuals and 13 stroke patients without motor or sensory loss participated. [Methods] Electroencephalograms were taken at rest and during vibratory stimulation. As a neurophysiological index of brain function, we measured the μ-rhythm, which is present mainly in the kinesthetic cortex and is attenuated by movement or motor imagery and compared the data using source localization analyses in the Standardized Low Resolution Brain Electromagnetic Tomography (sLORETA) program. [Results] At rest, μ-rhythms appeared in the sensorimotor and supplementary motor cortices in both healthy controls and stroke patients. Under vibratory stimulation, no μ-rhythm appeared in the sensorimotor cortex of either group. Moreover, in the supplementary motor area, which stores the motor imagery required for kinesthetic illusions, the μ-rhythms of patients were significantly stronger than those of the controls, although the μ-rhythms of both groups were reduced. Thus, differences in neural activity in the supplementary motor area were apparent between the subject groups. [Conclusion] Kinesthetic illusions do occur in patients with motor deficits due to stroke. The neural basis of the supplementary motor area in stroke patients may be functionally different from that found in healthy controls.

  11. Energetic materials identification by laser-induced breakdown spectroscopy combined with artificial neural network.

    Science.gov (United States)

    Farhadian, Amir Hossein; Tehrani, Masoud Kavosh; Keshavarz, Mohammad Hossein; Darbani, Seyyed Mohammad Reza

    2017-04-20

    In this study, for the first time to the best of our knowledge, a combination of the laser-induced breakdown spectroscopy (LIBS) technique and artificial neural network (ANN) analysis has been implemented for the identification of energetic materials, including TNT, RDX, black powder, and propellant. Also, aluminum, copper, inconel, and graphite have been used for more accurate investigation and comparison. After the LIBS test and spectrum acquisition on all samples in both air and argon ambient, optimized neural networks were designed by LIBS data. Based on input data, three ANN algorithms are proposed: the first is fed with the whole LIBS spectra in air (ANN1) and the second with the principle component analysis (PCA) scores of each spectrum in air (ANN2) and the other with the PCA scores of the spectrum in Ar (ANN3). According to the results, error of the network is very low in ANN2 and 3 and the best identification and discrimination was obtained by ANN3. After these, in order to validate and for more investigation of this combined method, we also used Al/RDX standard samples for analysis.

  12. Engrafted human induced pluripotent stem cell-derived anterior specified neural progenitors protect the rat crushed optic nerve.

    Directory of Open Access Journals (Sweden)

    Leila Satarian

    Full Text Available BACKGROUND: Degeneration of retinal ganglion cells (RGCs is a common occurrence in several eye diseases. This study examined the functional improvement and protection of host RGCs in addition to the survival, integration and neuronal differentiation capabilities of anterior specified neural progenitors (NPs following intravitreal transplantation. METHODOLOGY/PRINCIPAL FINDINGS: NPs were produced under defined conditions from human induced pluripotent stem cells (hiPSCs and transplanted into rats whose optic nerves have been crushed (ONC. hiPSCs were induced to differentiate into anterior specified NPs by the use of Noggin and retinoic acid. The hiPSC-NPs were labeled by green fluorescent protein or a fluorescent tracer 1,1' -dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI and injected two days after induction of ONC in hooded rats. Functional analysis according to visual evoked potential recordings showed significant amplitude recovery in animals transplanted with hiPSC-NPs. Retrograde labeling by an intra-collicular DiI injection showed significantly higher numbers of RGCs and spared axons in ONC rats treated with hiPSC-NPs or their conditioned medium (CM. The analysis of CM of hiPSC-NPs showed the secretion of ciliary neurotrophic factor, basic fibroblast growth factor, and insulin-like growth factor. Optic nerve of cell transplanted groups also had increased GAP43 immunoreactivity and myelin staining by FluoroMyelin™ which imply for protection of axons and myelin. At 60 days post-transplantation hiPSC-NPs were integrated into the ganglion cell layer of the retina and expressed neuronal markers. CONCLUSIONS/SIGNIFICANCE: The transplantation of anterior specified NPs may improve optic nerve injury through neuroprotection and differentiation into neuronal lineages. These NPs possibly provide a promising new therapeutic approach for traumatic optic nerve injuries and loss of RGCs caused by other diseases.

  13. Novel Strategy for Discrimination of Transcription Factor Binding Motifs Employing Mathematical Neural Network

    Science.gov (United States)

    Sugimoto, Asuka; Sumi, Takuya; Kang, Jiyoung; Tateno, Masaru

    2017-07-01

    Recognition in biological macromolecular systems, such as DNA-protein recognition, is one of the most crucial problems to solve toward understanding the fundamental mechanisms of various biological processes. Since specific base sequences of genome DNA are discriminated by proteins, such as transcription factors (TFs), finding TF binding motifs (TFBMs) in whole genome DNA sequences is currently a central issue in interdisciplinary biophysical and information sciences. In the present study, a novel strategy to create a discriminant function for discrimination of TFBMs by constituting mathematical neural networks (NNs) is proposed, together with a method to determine the boundary of signals (TFBMs) and noise in the NN-score (output) space. This analysis also leads to the mathematical limitation of discrimination in the recognition of features representing TFBMs, in an information geometrical manifold. Thus, the present strategy enables the identification of the whole space of TFBMs, right up to the noise boundary.

  14. Equivalent Neural Network Optimal Coefficients Using Forgetting Factor with Sliding Modes

    Directory of Open Access Journals (Sweden)

    Karen Alicia Aguilar Cruz

    2016-01-01

    Full Text Available The Artificial Neural Network (ANN concept is familiar in methods whose task is, for example, the identification or approximation of the outputs of complex systems difficult to model. In general, the objective is to determine online the adequate parameters to reach a better point-to-point convergence rate, so that this paper presents the parameter estimation for an equivalent ANN (EANN, obtaining a recursive identification for a stochastic system, firstly, with constant parameters and, secondly, with nonstationary output system conditions. Therefore, in the last estimation, the parameters also have stochastic properties, making the traditional approximation methods not adequate due to their losing of convergence rate. In order to give a solution to this problematic, we propose a nonconstant exponential forgetting factor (NCEFF with sliding modes, obtaining in almost all points an exponential convergence rate decreasing. Theoretical results of both identification stages are performed using MATLAB® and compared, observing improvement when the new proposal for nonstationary output conditions is applied.

  15. Nanofibers implant functionalized by neural growth factor as a strategy to innervate a bioengineered tooth.

    Science.gov (United States)

    Eap, Sandy; Bécavin, Thibault; Keller, Laetitia; Kökten, Tunay; Fioretti, Florence; Weickert, Jean-Luc; Deveaux, Etienne; Benkirane-Jessel, Nadia; Kuchler-Bopp, Sabine

    2014-03-01

    Current strategies for jaw reconstruction require multiple procedures, to repair the bone defect, to offer sufficient support, and to place the tooth implant. The entire procedure can be painful and time-consuming, and the desired functional repair can be achieved only when both steps are successful. The ability to engineer combined tooth and bone constructs, which would grow in a coordinated fashion with the surrounding tissues, could potentially improve the clinical outcomes and also reduce patient suffering. A unique nanofibrous and active implant for bone-tooth unit regeneration and also the innervation of this bioengineered tooth are demonstrated. A nanofibrous polycaprolactone membrane is functionalized with neural growth factor, along with dental germ, and tooth innervation follows. Such innervation allows complete functionality and tissue homeostasis of the tooth, such as dentinal sensitivity, odontoblast function, masticatory forces, and blood flow.

  16. Equivalent Neural Network Optimal Coefficients Using Forgetting Factor with Sliding Modes

    Science.gov (United States)

    2016-01-01

    The Artificial Neural Network (ANN) concept is familiar in methods whose task is, for example, the identification or approximation of the outputs of complex systems difficult to model. In general, the objective is to determine online the adequate parameters to reach a better point-to-point convergence rate, so that this paper presents the parameter estimation for an equivalent ANN (EANN), obtaining a recursive identification for a stochastic system, firstly, with constant parameters and, secondly, with nonstationary output system conditions. Therefore, in the last estimation, the parameters also have stochastic properties, making the traditional approximation methods not adequate due to their losing of convergence rate. In order to give a solution to this problematic, we propose a nonconstant exponential forgetting factor (NCEFF) with sliding modes, obtaining in almost all points an exponential convergence rate decreasing. Theoretical results of both identification stages are performed using MATLAB® and compared, observing improvement when the new proposal for nonstationary output conditions is applied. PMID:28058045

  17. Using an artificial neural network to predict carbon dioxide compressibility factor at high pressure and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Mohagheghian, Erfan [Memorial University of Newfoundland, St. John' s (Canada); Zafarian-Rigaki, Habiballah; Motamedi-Ghahfarrokhi, Yaser; Hemmati-Sarapardeh, Abdolhossein [Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2015-10-15

    Carbon dioxide injection, which is widely used as an enhanced oil recovery (EOR) method, has the potential of being coupled with CO{sub 2} sequestration and reducing the emission of greenhouse gas. Hence, knowing the compressibility factor of carbon dioxide is of a vital significance. Compressibility factor (Z-factor) is traditionally measured through time consuming, expensive and cumbersome experiments. Hence, developing a fast, robust and accurate model for its estimation is necessary. In this study, a new reliable model on the basis of feed forward artificial neural networks is presented to predict CO{sub 2} compressibility factor. Reduced temperature and pressure were selected as the input parameters of the proposed model. To evaluate and compare the results of the developed model with pre-existing models, both statistical and graphical error analyses were employed. The results indicated that the proposed model is more reliable and accurate compared to pre-existing models in a wide range of temperature (up to 1,273.15 K) and pressure (up to 140MPa). Furthermore, by employing the relevancy factor, the effect of pressure and temprature on the Z-factor of CO{sub 2} was compared for below and above the critical pressure of CO{sub 2}, and the physcially expected trends were observed. Finally, to identify the probable outliers and applicability domain of the proposed ANN model, both numerical and graphical techniques based on Leverage approach were performed. The results illustrated that only 1.75% of the experimental data points were located out of the applicability domain of the proposed model. As a result, the developed model is reliable for the prediction of CO{sub 2} compressibility factor.

  18. Induced Neural Differentiation of MMP-2 Cleaved (RADA)4 Drug Delivery Systems.

    Science.gov (United States)

    Koss, K; Tsui, C; Unsworth, L D

    2016-12-10

    (RADA)4 self-assembling peptides (SAPs) are promising for neural nanoscaffolds with on-demand drug delivery capabilities due to their automated synthesis, in-situ assembly, and potential for interaction with and release of biomolecules. Neuroinflammation cued on-demand drug release, due to up-regulated proteases, may well be vital in the treatment of several neurological diseases. In these conditions, releasing neurotrophic growth factors (NTFs) could potentially lead to neuroprotection and neurogenesis. As such, (RADA)4 was made with the high and low activity matrix metalloproteinase 2 (MMP-2) cleaved sequences, GPQG+IASQ (CP1) and GPQG+PAGQ (CP2), the brain-derived NTF secretion stimulating peptide MVG (DP1) and the ciliary NTF analogue DGGL (DP2). PC-12 cell culture was performed to assess bioactive substrate cell adhesion and NTF specific neuronal differentiation. The laminin-derived IKVAV peptide, known for neural cell attachment and interaction, was tethered to (RADA)4-IKVAV and mixed in increasing increments with (RADA)4 for this purpose. With 1 nanomolar MMP-2 treatment, product formation was observed to increase over a three day period, with (RADA)4/(RADA)4-CP1/CP2 mixture, however there was little difference between groups. Smaller CP1/CP2 concentrations displayed comparable (RADA)4 nanoscale morphology to higher concentrations. Acetylcholine esterase and neural differentiation was observed over 3 days with 1 nM MMP-2 treatment according to the following makeup: 8/1/1 (RADA)4/(RADA)4-IKVAV/(RADA)4-CP1/CP2-DP1/DP2. Signalling gradually increased in all groups, and neurite outgrowth was visible after three days.

  19. Neural Correlates of Learning from Induced Insight: A Case for Reward-Based Episodic Encoding

    Science.gov (United States)

    Kizilirmak, Jasmin M.; Thuerich, Hannes; Folta-Schoofs, Kristian; Schott, Björn H.; Richardson-Klavehn, Alan

    2016-01-01

    Experiencing insight when solving problems can improve memory formation for both the problem and its solution. The underlying neural processes involved in this kind of learning are, however, thus far insufficiently understood. Here, we conceptualized insight as the sudden understanding of a novel relationship between known stimuli that fits into existing knowledge and is accompanied by a positive emotional response. Hence, insight is thought to comprise associative novelty, schema congruency, and intrinsic reward, all of which are separately known to enhance memory performance. We examined the neural correlates of learning from induced insight with functional magnetic resonance imaging (fMRI) using our own version of the compound-remote-associates-task (CRAT) in which each item consists of three clue words and a solution word. (Pseudo-)Solution words were presented after a brief period of problem-solving attempts to induce either sudden comprehension (CRA items) or continued incomprehension (control items) at a specific time point. By comparing processing of the solution words of CRA with control items, we found induced insight to elicit activation of the rostral anterior cingulate cortex/medial prefrontal cortex (rACC/mPFC) and left hippocampus. This pattern of results lends support to the role of schema congruency (rACC/mPFC) and associative novelty (hippocampus) in the processing of induced insight. We propose that (1) the mPFC not only responds to schema-congruent information, but also to the detection of novel schemata, and (2) that the hippocampus responds to a form of associative novelty that is not just a novel constellation of familiar items, but rather comprises a novel meaningful relationship between the items—which was the only difference between our insight and no insight conditions. To investigate episodic long-term memory encoding, we compared CRA items whose solution word was recognized 24 h after encoding to those with forgotten solutions. We

  20. Neural correlates of learning from induced insight: A case for reward-based episodic encoding

    Directory of Open Access Journals (Sweden)

    Jasmin M. Kizilirmak

    2016-11-01

    Full Text Available Experiencing insight when solving problems can improve memory formation for both the problem and its solution. The underlying neural processes involved in this kind of learning are, however, thus far insufficiently understood. Here, we conceptualized insight as the sudden understanding of a novel relationship between known stimuli that fits into existing knowledge and is accompanied by a positive emotional response. Hence, insight is thought to comprise associative novelty, schema congruency, and intrinsic reward, all of which are separately known to enhance memory performance. We examined the neural correlates of learning from induced insight with functional magnetic resonance imaging (fMRI using our own version of the Compound-Remote-Associates-Task (CRAT in which each item consists of three clue words and a solution word. (Pseudo-Solution words were presented after a brief period of problem-solving attempts to induce either sudden comprehension (CRA items or continued incomprehension (control items at a specific time point. By comparing processing of the solution words of CRA with control items, we found induced insight to elicit activation of the rostral anterior cingulate cortex / medial prefrontal cortex (rACC/mPFC and left hippocampus. This pattern of results lends support to the role of schema congruency (rACC/mPFC and associative novelty (hippocampus in the processing of induced insight. We propose that (1 the mPFC not only responds to schema-congruent information, but also to the detection of novel schemata, and (2 that the hippocampus responds to a form of associative novelty that is not just a novel constellation of familiar items, but rather comprises a novel meaningful relationship between the items—which was the only difference between our insight and no insight conditions. To investigate episodic long-term memory encoding, we compared CRA items whose solution word was recognized 24h after encoding to those with forgotten

  1. Application of laser-induced breakdown spectroscopy (LIBS) and neural networks to olive oils analysis.

    Science.gov (United States)

    Caceres, Jorge O; Moncayo, Samuel; Rosales, Juan D; de Villena, Francisco Javier Manuel; Alvira, Fernando C; Bilmes, Gabriel M

    2013-09-01

    The adulteration and traceability of olive oils are serious problems in the olive oil industry. In this work, a method based on laser-induced breakdown spectroscopy (LIBS) and neural networks (NNs) has been developed and applied to the identification, quality control, traceability, and adulteration detection of extra virgin olive oils. Instant identification of the samples is achieved using a spectral library, which was obtained by analysis of representative samples using a single laser pulse and treatment by NNs. The samples used in this study belong to four countries. The study also included different regions of each country. The results obtained allow the identification of the oils tested with a certainty of more than 95%. Single-shot measurements were enough for clear identification of the samples. The method can be developed for automatic real-time, fast, reliable, and robust measurements, and the system can be packed into portable form for non-specialist users.

  2. Genomic factors that shape craniofacial outcome and neural crest vulnerability in FASD

    Directory of Open Access Journals (Sweden)

    Susan M. Smith

    2014-08-01

    Full Text Available Prenatal alcohol exposure (PAE causes distinctive facial characteristics in some pregnancies and not others; genetic factors may contribute to this differential vulnerability. Ethanol disrupts multiple events of neural crest development including induction, survival, migration, and differentiation. Animal models and genomic approaches have substantially advanced our understanding of the mechanisms underlying these facial changes. PAE during gastrulation produces craniofacial changes corresponding with human fetal alcohol syndrome. These result because PAE reduces prechordal plate extension and suppresses sonic hedgehog, leading to holoprosencephaly and malpositioned facial primordia. Haploinsufficiency in sonic hedgehog signaling increases vulnerability to facial deficits and may influence some PAE pregnancies. In contrast, PAE during early neurogenesis produces facial hypoplasia, preceded by neural crest reductions due to significant apoptosis. Factors mediating this apoptosis include intracellular calcium mobilization, elevated reactive oxygen species, and loss of trophic support from β-catenin/calcium, sonic hedgehog, and mTOR signaling. Genomewide SNP analysis links PDGF receptor genes with facial outcomes in human PAE. Multiple genomic-level comparisons of ethanol-sensitive and –resistant early embryos, in both mouse and chick, independently identify common candidate genes that may potentially modify craniofacial vulnerability, including ribosomal proteins, proteosome, RNA splicing, and focal adhesion. In summary, research using animal models with genome-level differences in ethanol vulnerability, as well as targeted loss- and gain-of-function mutants, has clarified the mechanisms mediating craniofacial change in PAE. The findings additionally suggest that craniofacial deficits may represent a gene-ethanol interaction for some affected individuals. Genetic-level changes may prime individuals toward greater sensitivity or resistance to

  3. An epidemiologic study of mitochondrial membrane transporter protein gene polymorphism and risk factors for neural tube defects in Shanxi, China

    Institute of Scientific and Technical Information of China (English)

    Zhizhen Liu; Jun Xie; Tiane Luo; Tao Zhang; Xia Zhao; Hong Zhao; Peizhen Li

    2012-01-01

    The present study involved a questionnaire survey of 156 mothers that gave birth to children with neural tube defects or had a history of pregnancy resulting in children with neural tube defects (case group) and 156 control mothers with concurrent healthy children (control group) as well as detection of mitochondrial membrane transporter protein gene [uncoupling protein 2 (UCP2)] polymorphism. The maternal UCP2 3' untranslated region (UTR) D/D genotype and D allele frequency were significantly higher in the case group compared with the control group (odds ratio (OR) 3.233; 95% confidence interval (CI) 1.103-9.476; P = 0.040; OR: 3.484; 95% CI: for neural tube defects 2.109-5.753; P < 0.001). Univariate and multivariate logistic regression analysis of risk factors for neural tube defects showed that a maternal UCP2 3' UTR D/D genotype was negatively interacted with the mothers'consumption of frequent fresh fruit and vegetables (S = 0.007), positively interacted with the mothers'frequency of germinated potato consumption (S = 2.15) and positively interacted with the mothers' body mass index (S = 3.50). These findings suggest that maternal UCP2 3' UTR gene polymorphism, pregnancy time, consumption of germinated potatoes and body mass index are associated with an increased risk for neural tube defects in children from mothers living in Shanxi province, China. Moreover, there is an apparent gene-environment interaction involved in the development of neural tube defects in offspring.

  4. Structural integration in hypoxia-inducible factors

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Dalei; Potluri, Nalini; Lu, Jingping; Kim, Youngchang; Rastinejad, Fraydoon

    2015-08-20

    The hypoxia-inducible factors (HIFs) coordinate cellular adaptations to low oxygen stress by regulating transcriptional programs in erythropoiesis, angiogenesis and metabolism. These programs promote the growth and progression of many tumours, making HIFs attractive anticancer targets. Transcriptionally active HIFs consist of HIF-alpha and ARNT (also called HIF-1 beta) subunits. Here we describe crystal structures for each of mouse HIF-2 alpha-ARNT and HIF-1 alpha-ARNT heterodimers in states that include bound small molecules and their hypoxia response element. A highly integrated quaternary architecture is shared by HIF-2 alpha-ARNT and HIF-1 alpha-ARNT, wherein ARNT spirals around the outside of each HIF-alpha subunit. Five distinct pockets are observed that permit small-molecule binding, including PAS domain encapsulated sites and an interfacial cavity formed through subunit heterodimerization. The DNA-reading head rotates, extends and cooperates with a distal PAS domain to bind hypoxia response elements. HIF-alpha mutations linked to human cancers map to sensitive sites that establish DNA binding and the stability of PAS domains and pockets.

  5. An investigation of the neural substrates of mind wandering induced by viewing traditional Chinese landscape paintings

    Directory of Open Access Journals (Sweden)

    Tingting eWang

    2015-01-01

    Full Text Available The present study was conducted to investigate whether the calming effect induced by viewing traditional Chinese landscape paintings would make disengagement from that mental state more difficult, as measured by performance on a cognitive control task. In Experiment 1 we examined the subjective experience of viewing traditional Chinese landscape paintings vs. realistic oil landscape paintings in a behavioral study. Our results confirmed that, as predicted, traditional Chinese landscape paintings induce greater levels of relaxation and mind wandering and lower levels of object-oriented absorption and recognition, compared to realistic oil landscape paintings. In Experiment 2 we used functional Magnetic Resonance Imaging (fMRI to explore the behavioural and neural effects of viewing traditional Chinese landscape paintings on a task requiring cognitive control (i.e., the flanker task—administered immediately following exposure to paintings. Contrary to our prediction, the behavioural data demonstrated that compared to realistic oil landscape paintings, exposure to traditional Chinese landscape paintings had no effect on performance on the flanker task. However, the neural data demonstrated an interaction effect such that there was greater activation in the inferior parietal cortex (IPC and the superior frontal gyrus (SFG on incongruent compared with congruent flanker trials when participants switched from viewing traditional Chinese landscape paintings to the flanker task than when they switched from realistic oil landscape paintings. These results suggest that switching from traditional Chinese landscape paintings placed greater demands on the brain’s attention and working memory networks during the flanker task than did switching from realistic oil landscape paintings.

  6. Prevention of valproic acid-induced neural tube defects by sildenafil citrate.

    Science.gov (United States)

    Tiboni, Gian Mario; Ponzano, Adalisa

    2015-08-15

    This study was undertaken to test the effects of sildenafil citrate (SC), a type 5 phosphodiesterase inhibitor, on valproic acid (VPA)-induced teratogenesis. On gestation day (GD) 8, ICR (CD-1) mice were treated by gastric intubation with SC at 0 (vehicle), 1.0, 2.5, 5.0 or 10mg/kg. One hour later, animals received a teratogenic dose of VPA (600mg/kg) or vehicle. Developmental endpoints were evaluated near the end of gestation. Twenty-eighth percent of fetuses exposed to VPA had neural tube defects (exencephaly). Pretreatment with SC at 2.5, 5.0 or 10mg/kg significantly reduced the rate of VPA-induced exencephaly to 15.9%, 13.7%, and 10.0%, respectively. Axial skeletal defects were observed in 75.8% of VPA-exposed fetuses. Pre-treatment with SC at 10mg/kg, but not at lower doses, significantly decreased the rate of skeletally affected fetuses to 61.6%. These results show that SC, which prolongs nitric oxide (NO) signaling action protects from VPA-induced teratogenesis.

  7. Using dose-surface maps to predict radiation-induced rectal bleeding: a neural network approach.

    Science.gov (United States)

    Buettner, Florian; Gulliford, Sarah L; Webb, Steve; Partridge, Mike

    2009-09-07

    The incidence of late-toxicities after radiotherapy can be modelled based on the dose delivered to the organ under consideration. Most predictive models reduce the dose distribution to a set of dose-volume parameters and do not take the spatial distribution of the dose into account. The aim of this study was to develop a classifier predicting radiation-induced rectal bleeding using all available information on the dose to the rectal wall. The dose was projected on a two-dimensional dose-surface map (DSM) by virtual rectum-unfolding. These DSMs were used as inputs for a classification method based on locally connected neural networks. In contrast to fully connected conventional neural nets, locally connected nets take the topology of the input into account. In order to train the nets, data from 329 patients from the RT01 trial (ISRCTN 47772397) were split into ten roughly equal parts. By using nine of these parts as a training set and the remaining part as an independent test set, a ten-fold cross-validation was performed. Ensemble learning was used and 250 nets were built from randomly selected patients from the training set. Out of these 250 nets, an ensemble of expert nets was chosen. The performances of the full ensemble and of the expert ensemble were quantified by using receiver-operator-characteristic (ROC) curves. In order to quantify the predictive power of the shape, ensembles of fully connected conventional neural nets based on dose-surface histograms (DSHs) were generated and their performances were quantified. The expert ensembles performed better than or equally as well as the full ensembles. The area under the ROC curve for the DSM-based expert ensemble was 0.64. The area under the ROC curve for the DSH-based expert ensemble equalled 0.59. This difference in performance indicates that not only volumetric, but also morphological aspects of the dose distribution are correlated to rectal bleeding after radiotherapy. Thus, the shape of the dose

  8. Repair of spinal cord injury by neural stem cells transfected with brain-derived neurotrophic factor-green fluorescent protein in rats A double effect of stem cells and growth factors

    Institute of Scientific and Technical Information of China (English)

    Yansong Wang; Gang Lü

    2010-01-01

    Brain-derived neurotrophic factor(BDNF)can significantly promote nerve regeneration and repair.High expression of the BDNF-green fluorescent protein(GFP)gene persists for a long time after transfection into neural stem cells.Nevertheless,little is known about the biological characteristics of BDNF-GFP modified nerve stem cells in vivo and their ability to induce BDNF expression or repair spinal cord injury.In the present study,we transplanted BDNF-GFP transgenic neural stem cells into a hemisection model of rats.Rats with BDNF-GFP stem cells exhibited significantly increased BDNF expression and better locomotor function compared with stem cells alone.Cellular therapy with BDNF-GFP transgenic stem cells can improve outcomes better than stem cells alone and may have therapeutic potential for spinal cord injury.

  9. Neural cell co-culture induced differentiation of bone marrow mesenchymal stem cells into neuronal-like cells

    Institute of Scientific and Technical Information of China (English)

    Nailong Yang; Lili Xu; Fen Yang

    2008-01-01

    BACKGROUND: It has been previously demonstrated that the neural cell microenvironment has the ability to induce differentiation of bone marrow mesenchymal stem cells (BMSCs) into the neural cells.OBJECTIVE: To establish a co-culture system of human BMSCs and neural cells, and to observe effects of this co-culture system on differentiation of human BMSCs into neural cells.DESIGN, TIME AND SETTING: A comparative observation experiment, performed at the Center Laboratory of the Affiliated Hospital of Medical College Qingdao University from October 2006 to December 2007.MATERIALS: Neural cells were obtained from human fetal brain tissue. BMSCs were harvested from female patients that underwent autonomous stem cell transplantation.METHODS: BMSCs in the co-culture group consisted of BMSCs and third passage neural cells. BMSCs in the control group were solely cultured in vitro.MAIN OUTCOME MEASURES: Morphological changes of BMSCs were observed, and expression of the neuronal specific marker, neuron-specific enolase (NSE), was analyzed by immunofluorescence staining after4-5-day co-culture.RESULTS: The number of neural cells in the co-culture group increased and the cells spread on the culture bottle surface. Radial dendrite formed and connected with each other. NSE-immunoreactive cells were also detected. The positive ratio of NSE-positive cells reached (32.7±11.5)%, with morphological characteristics similar to neuronal cells. Human BMSCs did not express NSE in the control group.CONCLUSION: The microenvironment provided by neurons induced differentiation of BMSCs into neuronal-like cells.

  10. Two outward potassium current types are expressed during the neural differentiation of neural stem cells

    OpenAIRE

    Bai, Ruiying; Gao, Guowei; Xing, Ying; Xue, Hong

    2013-01-01

    The electrophysiological properties of potassium ion channels are regarded as a basic index for determining the functional differentiation of neural stem cells. In this study, neural stem cells from the hippocampus of newborn rats were induced to differentiate with neurotrophic growth factor, and the electrophysiological properties of the voltage-gated potassium ion channels were observed. Immunofluorescence staining showed that the rapidly proliferating neural stem cells formed spheres in vi...

  11. Functional recovery after transplantation of neural stem cells modified by brain-derived neurotrophic factor in rats with cerebral ischaemia.

    Science.gov (United States)

    Zhu, J M; Zhao, Y Y; Chen, S D; Zhang, W H; Lou, L; Jin, X

    2011-01-01

    Functional recovery after transplantation of brain-derived neurotrophic factor (BDNF)-modified neural stem cells (NSCs) was evaluated in a rat model of cerebral ischaemia damage induced by temporary middle cerebral artery occlusion (tMCAO). Western blotting and enzyme-linked immunosorbent assay demonstrated upregulated BDNF protein expression by rat embryonic NSCs transfected with the human BDNF gene (BDNF-NSCs). BDNF-NSCs stimulated neurite outgrowth in cocultured dorsal root ganglion neurons, suggesting that BDNF increased neurogenesis in vitro. In vivo, BDNF promoted recovery of tMCAO. Phosphate-buffered saline, untransformed NSCs or BDNF-NSCs were introduced into the penumbra zone of the right striatum of tMCAO rats and neurological function deficit was assessed for up to 12 weeks using the neurological severity score (NSS). The NSS was significantly lower in the BDNF-NSC transfected transplant group than in all the other groups from week 10. BDNF-NSCs recovered 1 week after transplantation expressed BDNF protein. Transplanted NSCs had differentiated into mature neurons 12 weeks after transplantation. Transgenic NSCs have potential as a therapeutic agent for brain ischaemia.

  12. The Master Neural Transcription Factor BRN2 Is an Androgen Receptor-Suppressed Driver of Neuroendocrine Differentiation in Prostate Cancer.

    Science.gov (United States)

    Bishop, Jennifer L; Thaper, Daksh; Vahid, Sepideh; Davies, Alastair; Ketola, Kirsi; Kuruma, Hidetoshi; Jama, Randy; Nip, Ka Mun; Angeles, Arkhjamil; Johnson, Fraser; Wyatt, Alexander W; Fazli, Ladan; Gleave, Martin E; Lin, Dong; Rubin, Mark A; Collins, Colin C; Wang, Yuzhuo; Beltran, Himisha; Zoubeidi, Amina

    2017-01-01

    Mechanisms controlling the emergence of lethal neuroendocrine prostate cancer (NEPC), especially those that are consequences of treatment-induced suppression of the androgen receptor (AR), remain elusive. Using a unique model of AR pathway inhibitor-resistant prostate cancer, we identified AR-dependent control of the neural transcription factor BRN2 (encoded by POU3F2) as a major driver of NEPC and aggressive tumor growth, both in vitro and in vivo Mechanistic studies showed that AR directly suppresses BRN2 transcription, which is required for NEPC, and BRN2-dependent regulation of the NEPC marker SOX2. Underscoring its inverse correlation with classic AR activity in clinical samples, BRN2 expression was highest in NEPC tumors and was significantly increased in castration-resistant prostate cancer compared with adenocarcinoma, especially in patients with low serum PSA. These data reveal a novel mechanism of AR-dependent control of NEPC and suggest that targeting BRN2 is a strategy to treat or prevent neuroendocrine differentiation in prostate tumors.

  13. Production of Tuber-Inducing Factor

    Science.gov (United States)

    Stutte, Gary W.; Yorio, Neil C.

    2006-01-01

    A process for making a substance that regulates the growth of potatoes and some other economically important plants has been developed. The process also yields an economically important by-product: potatoes. The particular growth-regulating substance, denoted tuber-inducing factor (TIF), is made naturally by, and acts naturally on, potato plants. The primary effects of TIF on potato plants are reducing the lengths of the main shoots, reducing the numbers of nodes on the main stems, reducing the total biomass, accelerating the initiation of potatoes, and increasing the edible fraction (potatoes) of the overall biomass. To some extent, these effects of TIF can override environmental effects that typically inhibit the formation of tubers. TIF can be used in the potato industry to reduce growth time and increase harvest efficiency. Other plants that have been observed to be affected by TIF include tomatoes, peppers, radishes, eggplants, marigolds, and morning glories. In the present process, potatoes are grown with their roots and stolons immersed in a nutrient solution in a recirculating hydroponic system. From time to time, a nutrient replenishment solution is added to the recirculating nutrient solution to maintain the required nutrient concentration, water is added to replace water lost from the recirculating solution through transpiration, and an acid or base is added, as needed, to maintain the recirculating solution at a desired pH level. The growing potato plants secrete TIF into the recirculating solution. The concentration of TIF in the solution gradually increases to a range in which the TIF regulates the growth of the plants.

  14. Abnormal cardiovascular response to exercise in hypertension: contribution of neural factors.

    Science.gov (United States)

    Mitchell, Jere H

    2017-06-01

    During both dynamic (e.g., endurance) and static (e.g., strength) exercise there are exaggerated cardiovascular responses in hypertension. This includes greater increases in blood pressure, heart rate, and efferent sympathetic nerve activity than in normal controls. Two of the known neural factors that contribute to this abnormal cardiovascular response are the exercise pressor reflex (EPR) and functional sympatholysis. The EPR originates in contracting skeletal muscle and reflexly increases sympathetic efferent nerve activity to the heart and blood vessels as well as decreases parasympathetic efferent nerve activity to the heart. These changes in autonomic nerve activity cause an increase in blood pressure, heart rate, left ventricular contractility, and vasoconstriction in the arterial tree. However, arterial vessels in the contracting skeletal muscle have a markedly diminished vasoconstrictor response. The markedly diminished vasoconstriction in contracting skeletal muscle has been termed functional sympatholysis. It has been shown in hypertension that there is an enhanced EPR, including both its mechanoreflex and metaboreflex components, and an impaired functional sympatholysis. These conditions set up a positive feedback or vicious cycle situation that causes a progressively greater decrease in the blood flow to the exercising muscle. Thus these two neural mechanisms contribute significantly to the abnormal cardiovascular response to exercise in hypertension. In addition, exercise training in hypertension decreases the enhanced EPR, including both mechanoreflex and metaboreflex function, and improves the impaired functional sympatholysis. These two changes, caused by exercise training, improve the muscle blood flow to exercising muscle and cause a more normal cardiovascular response to exercise in hypertension. Copyright © 2017 the American Physiological Society.

  15. Study of brain-derived neurotrophic factor gene transgenic neural stem cells in the rat retina

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xue-mei; YUAN Hui-ping; WU Dong-lai; ZHOU Xin-rong; SUN Da-wei; LI Hong-yi; SHAO Zheng-bo

    2009-01-01

    Background Neural stem cells (NSCs) transplantation and gene therapy have been widely investigated for treating the cerebullar and myelonic injuries, however, studies on the ophthalmology are rare. The aim of this study was to investigate the migration and differentiation of brain-derived neurotrophic factor (BDNF) gene transgenic NSCs transplanted into the normal rat retinas. Methods NSCs were cultured and purified in vitro and infected with recombinant retrovirus pLXSN-BDNF and pLXSN respectively, to obtain the BDNF overexpressed NSCs (BDNF-NSCs) and control cells (p-NSCs). The expression of BDNF genes in two transgenic NSCs and untreated NSCs were measured by fluorescent quantitative polymerase chain reaction (FQ-PCR) and enzyme-linked immunosorbent assay (ELISA). BDNF-NSCs and NSCs were infected with adeno-associated viruses-enhanced green fluorescent protein (AAV-EGFP) to track them in vivo and served as donor cells for transplantation into the subretinal space of normal rat retinas, phosphated buffer solution (PBS) served as pseudo transplantation for a negative control. Survival, migration, and differentiation of donor cells in host retinas were observed and analyzed with Heidelberg retina angiograph (HRA) and immunohistochemistry, respectively. Results NSCs were purified successfully by limiting dilution assay. The expression of BDNF gene in BDNF-NSCs was the highest among three groups both at mRNA level tested by FQ-PCR (P<0.05) and at protein level measured by ELISA (P<0.05), which showed that BDNF was overexpressed in BDNF-NSCs. The results of HRA demonstrated that graft cells could survive well and migrate into the host retinas, while the immunohistochemical analysis revealed that transplanted BDNF-NSCs differentiated into neuron more efficiently compared with the control NSCs 2 months after transplantation. Conclusions The seed cells of NSCs highly secreting BDNF were established. BDNF can promote NSCs to migrate and differentiate into neural cells in

  16. Energy efficient low-noise neural recording amplifier with enhanced noise efficiency factor.

    Science.gov (United States)

    Majidzadeh, V; Schmid, A; Leblebici, Y

    2011-06-01

    This paper presents a neural recording amplifier array suitable for large-scale integration with multielectrode arrays in very low-power microelectronic cortical implants. The proposed amplifier is one of the most energy-efficient structures reported to date, which theoretically achieves an effective noise efficiency factor (NEF) smaller than the limit that can be achieved by any existing amplifier topology, which utilizes a differential pair input stage. The proposed architecture, which is referred to as a partial operational transconductance amplifier sharing architecture, results in a significant reduction of power dissipation as well as silicon area, in addition to the very low NEF. The effect of mismatch on crosstalk between channels and the tradeoff between noise and crosstalk are theoretically analyzed. Moreover, a mathematical model of the nonlinearity of the amplifier is derived, and its accuracy is confirmed by simulations and measurements. For an array of four neural amplifiers, measurement results show a midband gain of 39.4 dB and a -3-dB bandwidth ranging from 10 Hz to 7.2 kHz. The input-referred noise integrated from 10 Hz to 100 kHz is measured at 3.5 μVrms and the power consumption is 7.92 μW from a 1.8-V supply, which corresponds to NEF = 3.35. The worst-case crosstalk and common-mode rejection ratio within the desired bandwidth are - 43.5 dB and 70.1 dB, respectively, and the active silicon area of each amplifier is 256 μm × 256 μm in 0.18-μm complementary metal-oxide semiconductor technology.

  17. Factor-Reduced Human Induced Pluripotent Stem Cells Efficiently Differentiate into Neurons Independent of the Number of Reprogramming Factors.

    Science.gov (United States)

    Hermann, Andreas; Kim, Jeong Beom; Srimasorn, Sumitra; Zaehres, Holm; Reinhardt, Peter; Schöler, Hans R; Storch, Alexander

    2016-01-01

    Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) by overexpression of the transcription factors OCT4, SOX2, KLF4, and c-Myc holds great promise for the development of personalized cell replacement therapies. In an attempt to minimize the risk of chromosomal disruption and to simplify reprogramming, several studies demonstrated that a reduced set of reprogramming factors is sufficient to generate iPSC. We recently showed that a reduction of reprogramming factors in murine cells not only reduces reprogramming efficiency but also may worsen subsequent differentiation. To prove whether this is also true for human cells, we compared the efficiency of neuronal differentiation of iPSC generated from fetal human neural stem cells with either one (OCT4; hiPSC1F-NSC) or two (OCT4, KLF4; hiPSC2F-NSC) reprogramming factors with iPSC produced from human fibroblasts using three (hiPSC3F-FIB) or four reprogramming factors (hiPSC4F-FIB). After four weeks of coculture with PA6 stromal cells, neuronal differentiation of hiPSC1F-NSC and hiPSC2F-NSC was as efficient as iPSC3F-FIB or iPSC4F-FIB. We conclude that a reduction of reprogramming factors in human cells does reduce reprogramming efficiency but does not alter subsequent differentiation into neural lineages. This is of importance for the development of future application of iPSC in cell replacement therapies.

  18. Factor-Reduced Human Induced Pluripotent Stem Cells Efficiently Differentiate into Neurons Independent of the Number of Reprogramming Factors

    Directory of Open Access Journals (Sweden)

    Andreas Hermann

    2016-01-01

    Full Text Available Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs by overexpression of the transcription factors OCT4, SOX2, KLF4, and c-Myc holds great promise for the development of personalized cell replacement therapies. In an attempt to minimize the risk of chromosomal disruption and to simplify reprogramming, several studies demonstrated that a reduced set of reprogramming factors is sufficient to generate iPSC. We recently showed that a reduction of reprogramming factors in murine cells not only reduces reprogramming efficiency but also may worsen subsequent differentiation. To prove whether this is also true for human cells, we compared the efficiency of neuronal differentiation of iPSC generated from fetal human neural stem cells with either one (OCT4; hiPSC1F-NSC or two (OCT4, KLF4; hiPSC2F-NSC reprogramming factors with iPSC produced from human fibroblasts using three (hiPSC3F-FIB or four reprogramming factors (hiPSC4F-FIB. After four weeks of coculture with PA6 stromal cells, neuronal differentiation of hiPSC1F-NSC and hiPSC2F-NSC was as efficient as iPSC3F-FIB or iPSC4F-FIB. We conclude that a reduction of reprogramming factors in human cells does reduce reprogramming efficiency but does not alter subsequent differentiation into neural lineages. This is of importance for the development of future application of iPSC in cell replacement therapies.

  19. Transforming growth factor beta1 regulates melanocyte proliferation and differentiation in mouse neural crest cells via stem cell factor/KIT signaling.

    Science.gov (United States)

    Kawakami, Tamihiro; Soma, Yoshinao; Kawa, Yoko; Ito, Masaru; Yamasaki, Emiko; Watabe, Hidenori; Hosaka, Eri; Yajima, Kenji; Ohsumi, Kayoko; Mizoguchi, Masako

    2002-03-01

    Stem cell factor is essential to the migration and differentiation of melanocytes during embryogenesis based on the observation that mutations in either the stem cell factor gene, or its ligand, KIT, result in defects in coat pigmentation in mice. Stem cell factor is also required for the survival of melanocyte precursors while they are migrating towards the skin. Transforming growth factor beta1 has been implicated in the regulation of both cellular proliferation and differentiation. NCC-melb4, an immortal cloned cell line, was cloned from a mouse neural crest cell. NCC-melb4 cells provide a model to study the specific stage of differentiation and proliferation of melanocytes. They also express KIT as a melanoblast marker. Using the NCC-melb4 cell line, we investigated the effect of transforming growth factor beta1 on the differentiation and proliferation of immature melanocyte precursors. Immunohistochemically, NCC-melb4 cells showed transforming growth factor beta1 expression. The anti-transforming growth factor beta1 antibody inhibited the cell growth, and downregulated the KIT protein and mRNA expression. To investigate further the activation of autocrine transforming growth factor beta1, NCC-melb4 cells were incubated in nonexogenous transforming growth factor beta1 culture medium. KIT protein decreased with anti-transforming growth factor beta1 antibody concentration in a concentration-dependent manner. We concluded that in NCC-melb4 cells, transforming growth factor beta1 promotes melanocyte precursor proliferation in autocrine and/or paracrine regulation. We further investigated the influence of transforming growth factor beta1 in vitro using a neural crest cell primary culture system from wild-type mice. Anti-transforming growth factor beta1 antibody decreased the number of KIT positive neural crest cell. In addition, the anti-transforming growth factor beta1 antibody supplied within the wild-type neural crest explants abolished the growth of the neural

  20. Spirulina promotes stem cell genesis and protects against LPS induced declines in neural stem cell proliferation.

    Directory of Open Access Journals (Sweden)

    Adam D Bachstetter

    Full Text Available Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1beta in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS. To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg. The following day the rats were injected with BrdU (50 mg/kg b.i.d. i.p. and were sacrificed 24 hours after the first injection of BrdU. Quantification of the BrdU positive cells in the subgranular zone of the dentate gyrus demonstrated a decrease in proliferation of the stem/progenitor cells in the hippocampus as a result of the LPS insult. Furthermore, the diet supplemented with spirulina was able to negate the LPS induced decrease in stem/progenitor cell proliferation. In a second set of studies we examined the effects of spirulina either alone or in combination with a proprietary formulation (NT-020 of blueberry, green tea, vitamin D3 and carnosine on the function of bone marrow and CD34+ cells in vitro. Spirulina had small effects on its own and more than additive effects in combination with NT-020 to promote mitochondrial respiration and/or proliferation of these cells in culture. When examined on neural stem cells in culture spirulina increased proliferation at baseline and protected

  1. Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation

    Science.gov (United States)

    Bachstetter, Adam D.; Jernberg, Jennifer; Schlunk, Andrea; Vila, Jennifer L.; Hudson, Charles; Cole, Michael J.; Shytle, R. Douglas; Tan, Jun; Sanberg, Paul R.; Sanberg, Cyndy D.; Borlongan, Cesario; Kaneko, Yuji; Tajiri, Naoki; Gemma, Carmelina; Bickford, Paula C.

    2010-01-01

    Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1β in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS). To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg). The following day the rats were injected with BrdU (50 mg/kg b.i.d. i.p.) and were sacrificed 24 hours after the first injection of BrdU. Quantification of the BrdU positive cells in the subgranular zone of the dentate gyrus demonstrated a decrease in proliferation of the stem/progenitor cells in the hippocampus as a result of the LPS insult. Furthermore, the diet supplemented with spirulina was able to negate the LPS induced decrease in stem/progenitor cell proliferation. In a second set of studies we examined the effects of spirulina either alone or in combination with a proprietary formulation (NT-020) of blueberry, green tea, vitamin D3 and carnosine on the function of bone marrow and CD34+ cells in vitro. Spirulina had small effects on its own and more than additive effects in combination with NT-020 to promote mitochondrial respiration and/or proliferation of these cells in culture. When examined on neural stem cells in culture spirulina increased proliferation at baseline and protected against the negative

  2. Identifying environmental risk factors for human neural tube defects before and after folic acid supplementation

    Directory of Open Access Journals (Sweden)

    Li Xinhu

    2009-10-01

    Full Text Available Abstract Background Birth defects are a major cause of infant mortality and disability in many parts of the world. Neural tube defects (NTDs are one of the most common types of birth defects. In 2001, the Chinese population and family planning commission initiated a national intervention program for the prevention of birth defects. A key step in the program was the introduction of folic acid supplementation. Of interest in the present study was to determine whether folic acid supplementation has the same protective effect on NTDs under various geographical and socioeconomic conditions within the Chinese population and the nature in which the influence of environmental factors varied after folic acid supplementation. Methods In this study, Heshun was selected as the region of interest as a surrogate for helping to answer some of the questions raised in this study on the impact of the intervention program. Spatial filtering in combination with GIS software was used to detect annual potential clusters from 1998 to 2005 in Heshun, and Kruskal-wallis test and multivariate regression were applied to identify the environmental risk factors for NTDs among various regions. Results In 1998, a significant (p Conclusion This suggests that the government needs to adapt the intervention measures according to local conditions. More attention needs to be paid to the poor and to people living in areas near coal mines.

  3. Fibroblast growth factor-regulated palmitoylation of the neural cell adhesion molecule determines neuronal morphogenesis.

    Science.gov (United States)

    Ponimaskin, Evgeni; Dityateva, Galina; Ruonala, Mika O; Fukata, Masaki; Fukata, Yuko; Kobe, Fritz; Wouters, Fred S; Delling, Markus; Bredt, David S; Schachner, Melitta; Dityatev, Alexander

    2008-09-03

    During development of the nervous system, short- and long-range signals cooperate to promote axonal growth, guidance, and target innervation. Particularly, a short-range signal transducer, the neural cell adhesion molecule (NCAM), stimulates neurite outgrowth via mechanisms that require posttranslational modification of NCAM and signaling via receptors to a long-range messenger, the fibroblast growth factor (FGF). In the present study we further characterized a mechanism which regulates the functional interplay between NCAM and FGF receptor(s). We show that activation of FGF receptor(s) by FGF2 leads to palmitoylation of the two major transmembrane NCAM isoforms, NCAM140 and NCAM180, translocation of NCAM to GM1 ganglioside-containing lipid rafts, and stimulation of neurite outgrowth of hippocampal neurons. Ablation of NCAM, mutation of NCAM140 or NCAM180 palmitoylation sites, or pharmacological suppression of NCAM signaling inhibited FGF2-stimulated neurite outgrowth. Of the 23 members of the aspartate-histidine-histidine-cysteine (DHHC) domain containing proteins, DHHC-7 most strongly stimulated palmitoylation of NCAM, and enzyme activity was enhanced by FGF2. Thus, our study uncovers a molecular mechanism by which a growth factor regulates neuronal morphogenesis via activation of palmitoylation, which in turn modifies subcellular location and thus signaling via an adhesion molecule.

  4. Effect of age on the gene expression of neural-restrictive silencing factor NRSF/REST.

    Science.gov (United States)

    Mori, Nozomu; Mizuno, Takafumi; Murai, Kiyohito; Nakano, Itsuko; Yamashita, Hitoshi

    2002-01-01

    Aging affects a wide range of gene expression changes in the nervous system. Such effects could be attributed to random changes in the environment with age around each gene, but also could be caused by selective changes in a limited set of key regulatory transcription factors and/or chromatin remodeling components. To approach the question of whether neural-restrictive silencer factor NRSF, a key determinant of the neuron-specific gene expression, is involved in these changes, we examined the levels of NRSF in the rat brain and dosal root ganglia during aging by semi-quantitative reverse transcriptase-mediated polymerase chain reaction (PCR) (RT-PCR). Complementary expression profiles of transcripts of NRSF and SCG10 in the mature brain were shown by in situ hybridization. Neither the mRNA levels of NRSF nor a splicing variant NRnV were changed, at least in rats up to 26 months old. The gene expression level of SCG10, one of the NRSF targets, was also unaffected by age. The stable expression of SCG10 transcripts in aging was confirmed by in situ hybridization. The NRS-binding ability of NRSF was also unchanged significantly in the nuclear extracts of aged rat brain. These results suggest that the genetic machinery associated with the NRS-NRSF system is well maintained during aging.

  5. Diet Induced Obesity in Sprague Dawley Rats Causes Microvascular and Neural Dysfunction

    Science.gov (United States)

    Davidson, Eric P.; Coppey, Lawrence J.; Calcutt, Nigel A.; Oltman, Christine L.; Yorek, Mark A.

    2010-01-01

    Background The objective was to determine the effect of diet induced obesity (DIO) on microvascular and neural function. Methods Rats were fed a standard or high fat diet for up to 32 weeks. Measurements were performed of vasodilation in epineurial arterioles by videomicroscopy, endoneurial blood flow by hydrogen clearance, nerve conduction velocity by electrical stimulation, size-frequency distribution of myelinated fibers of the sciatic nerve, intraepidermal nerve fiber density using confocal microscopy and thermal nociception using the Hargreaves method. Results Rats fed a high fat diet for 32 weeks developed sensory neuropathy as indicated by slowing of sensory nerve conduction velocity and thermal hypoalgesia. Motor nerve conduction velocity and endoneurial blood flow were not impaired. Mean axonal diameter of myelinated fibers of the sciatic nerve was unchanged in high fat fed rats compared to control. Intraepidermal nerve fiber density was significantly reduced in high fat fed rats. Vascular relaxation to acetylcholine and calcitonin gene-related peptide was decreased and expression of neutral endopeptidase (NEP) increased in epineurial arterioles of rats fed a high fat diet. In contrast, insulin-mediated vascular relaxation was increased in epineurial arterioles. NEP activity was significantly increased in the skin of the hindpaw. Markers of oxidative stress were increased in the aorta and serum of high fat fed rats but not in epineurial arterioles. Conclusion Chronic obesity causes microvascular and neural dysfunction. This is associated with increased expression of NEP but not oxidative stress in epineurial arterioles. NEP degrades vasoactive peptides which may explain the decrease in microvascular function. PMID:20503263

  6. Closed-loop neural stimulation for pentylenetetrazole-induced seizures in zebrafish

    Directory of Open Access Journals (Sweden)

    Ricardo Pineda

    2013-01-01

    Neural stimulation can reduce the frequency of seizures in persons with epilepsy, but rates of seizure-free outcome are low. Vagus nerve stimulation prevents seizures by continuously activating noradrenergic projections from the brainstem to the cortex. Cortical norepinephrine then increases GABAergic transmission and increases seizure threshold. Another approach, responsive nervous stimulation, prevents seizures by reactively shocking the seizure onset zone in precise synchrony with seizure onset. The electrical shocks abort seizures before they can spread and manifest clinically. The goal of this study was to determine whether a hybrid platform in which brainstem activation triggered in response to impending seizure activity could prevent seizures. We chose the zebrafish as a model organism for this study because of its ability to recapitulate human disease, in conjunction with its innate capacity for tightly controlled high-throughput experimentation. We first set out to determine whether electrical stimulation of the zebrafish hindbrain could have an anticonvulsant effect. We found that pulse train electrical stimulation of the hindbrain significantly increased the latency to onset of pentylenetetrazole-induced seizures, and that this apparent anticonvulsant effect was blocked by noradrenergic antagonists, as is also the case with rodents and humans. We also found that the anticonvulsant effect of hindbrain stimulation could be potentiated by reactive triggering of single pulse electrical stimulations in response to impending seizure activity. Finally, we found that the rate of stimulation triggering was directly proportional to pentylenetetrazole concentration and that the stimulation rate was reduced by the anticonvulsant valproic acid and by larger stimulation currents. Taken as a whole, these results show that that the anticonvulsant effect of brainstem activation can be efficiently utilized by reactive triggering, which suggests that alternative

  7. Sound Waves Induce Neural Differentiation of Human Bone Marrow-Derived Mesenchymal Stem Cells via Ryanodine Receptor-Induced Calcium Release and Pyk2 Activation.

    Science.gov (United States)

    Choi, Yura; Park, Jeong-Eun; Jeong, Jong Seob; Park, Jung-Keug; Kim, Jongpil; Jeon, Songhee

    2016-10-01

    Mesenchymal stem cells (MSCs) have shown considerable promise as an adaptable cell source for use in tissue engineering and other therapeutic applications. The aims of this study were to develop methods to test the hypothesis that human MSCs could be differentiated using sound wave stimulation alone and to find the underlying mechanism. Human bone marrow (hBM)-MSCs were stimulated with sound waves (1 kHz, 81 dB) for 7 days and the expression of neural markers were analyzed. Sound waves induced neural differentiation of hBM-MSC at 1 kHz and 81 dB but not at 1 kHz and 100 dB. To determine the signaling pathways involved in the neural differentiation of hBM-MSCs by sound wave stimulation, we examined the Pyk2 and CREB phosphorylation. Sound wave induced an increase in the phosphorylation of Pyk2 and CREB at 45 min and 90 min, respectively, in hBM-MSCs. To find out the upstream activator of Pyk2, we examined the intracellular calcium source that was released by sound wave stimulation. When we used ryanodine as a ryanodine receptor antagonist, sound wave-induced calcium release was suppressed. Moreover, pre-treatment with a Pyk2 inhibitor, PF431396, prevented the phosphorylation of Pyk2 and suppressed sound wave-induced neural differentiation in hBM-MSCs. These results suggest that specific sound wave stimulation could be used as a neural differentiation inducer of hBM-MSCs.

  8. Insulin-like growth factor actions during development of neural stem cells and progenitors in the central nervous system.

    Science.gov (United States)

    Ye, Ping; D'Ercole, A Joseph

    2006-01-01

    Insulin-like growth factor-I (IGF-I) plays a key role in normal development. Recent studies show that IGF-I exerts a wide variety actions in the central nervous system during development as well as in adulthood. This report reviews recent developments on IGF-I actions and its mechanisms in the central nervous system, with a focus on its actions during the development of neural stem cells and progenitors. Available data strongly indicate that IGF-I shortens the length of the cell cycle in neuron progenitors during embryonic life and has an influence on the growth of all neural cell types. The phosphatidylinositol-3 kinase/Akt and mitogen-activated protein kinase pathways seem to be the predominant mediators of IGF-I-stimulated neural cell proliferation and survival. IGF-I actions, however, likely depend on cell type, developmental stage, and microenvironmental milieu.

  9. Generation of Induced Pluripotent Stem Cells from Hair Follicle Bulge Neural Crest Stem Cells

    NARCIS (Netherlands)

    Ma, Ming-San; Czepiel, Marcin; Krause, Tina; Schaefer, Karl-Herbert; Boddeke, Erik; Copray, Sjef

    2014-01-01

    Induced pluripotent stem cells (iPSCs) are promising candidates for the study of disease models as well as for tissue engineering purposes. Part of a strategy to develop safe reprogramming technique is reducing the number of exogenous reprogramming factors. Some cells types are more prone to reprogr

  10. Generation of Induced Pluripotent Stem Cells from Hair Follicle Bulge Neural Crest Stem Cells

    NARCIS (Netherlands)

    Ma, Ming-San; Czepiel, Marcin; Krause, Tina; Schaefer, Karl-Herbert; Boddeke, Erik; Copray, Sjef

    2014-01-01

    Induced pluripotent stem cells (iPSCs) are promising candidates for the study of disease models as well as for tissue engineering purposes. Part of a strategy to develop safe reprogramming technique is reducing the number of exogenous reprogramming factors. Some cells types are more prone to

  11. NeuroD1 mediates nicotine-induced migration and invasion via regulation of the nicotinic acetylcholine receptor subunits in a subset of neural and neuroendocrine carcinomas.

    Science.gov (United States)

    Osborne, Jihan K; Guerra, Marcy L; Gonzales, Joshua X; McMillan, Elizabeth A; Minna, John D; Cobb, Melanie H

    2014-06-01

    Cigarette smoking is a major risk factor for acquisition of small cell lung cancer (SCLC). A role has been demonstrated for the basic helix-loop-helix transcription factor NeuroD1 in the pathogenesis of neural and neuroendocrine lung cancer, including SCLC. In the present study we investigate the possible function of NeuroD1 in established tumors, as well as actions early on in pathogenesis, in response to nicotine. We demonstrate that nicotine up-regulates NeuroD1 in immortalized normal bronchial epithelial cells and a subset of undifferentiated carcinomas. Increased expression of NeuroD1 subsequently leads to regulation of expression and function of the nicotinic acetylcholine receptor subunit cluster of α3, α5, and β4. In addition, we find that coordinated expression of these subunits by NeuroD1 leads to enhanced nicotine-induced migration and invasion, likely through changes in intracellular calcium. These findings suggest that aspects of the pathogenesis of neural and neuroendocrine lung cancers may be affected by a nicotine- and NeuroD1-induced positive feedback loop.

  12. Partial Least Squares and Neural Networks for Quantitative Calibration of Laser-induced Breakdown Spectroscopy (LIBs) of Geologic Samples

    Science.gov (United States)

    Anderson, R. B.; Morris, Richard V.; Clegg, S. M.; Humphries, S. D.; Wiens, R. C.; Bell, J. F., III; Mertzman, S. A.

    2010-01-01

    The ChemCam instrument [1] on the Mars Science Laboratory (MSL) rover will be used to obtain the chemical composition of surface targets within 7 m of the rover using Laser Induced Breakdown Spectroscopy (LIBS). ChemCam analyzes atomic emission spectra (240-800 nm) from a plasma created by a pulsed Nd:KGW 1067 nm laser. The LIBS spectra can be used in a semiquantitative way to rapidly classify targets (e.g., basalt, andesite, carbonate, sulfate, etc.) and in a quantitative way to estimate their major and minor element chemical compositions. Quantitative chemical analysis from LIBS spectra is complicated by a number of factors, including chemical matrix effects [2]. Recent work has shown promising results using multivariate techniques such as partial least squares (PLS) regression and artificial neural networks (ANN) to predict elemental abundances in samples [e.g. 2-6]. To develop, refine, and evaluate analysis schemes for LIBS spectra of geologic materials, we collected spectra of a diverse set of well-characterized natural geologic samples and are comparing the predictive abilities of PLS, cascade correlation ANN (CC-ANN) and multilayer perceptron ANN (MLP-ANN) analysis procedures.

  13. The neural background of hyper-emotional aggression induced by post-weaning social isolation.

    Science.gov (United States)

    Toth, Mate; Tulogdi, Aron; Biro, Laszlo; Soros, Petra; Mikics, Eva; Haller, Jozsef

    2012-07-15

    Post-weaning social isolation in rats is believed to model symptoms of early social neglect-induced externalizing problems including aggression-related problems. We showed earlier that rats reared in social isolation were hyper-aroused during aggressive contacts, delivered substantially more attacks that were poorly signaled and were preferentially aimed at vulnerable body parts of opponents (head, throat and belly). Here we studied the neural background of this type of aggression by assessing the expression of the activation marker c-Fos in 22 brain areas of male Wistar rats submitted to resident-intruder conflicts. Post-weaning social isolation readily produced the behavioral alterations noticed earlier. Social isolation significantly increased the activation of brain areas that are known to directly or indirectly control inter-male aggression. Particularly, the medial and lateral orbitofrontal cortices, anterior cingulate cortex, bed nucleus of the stria terminalis, medial and basolateral amygdala, hypothalamic attack area, hypothalamic paraventricular nucleus and locus coeruleus showed increased activations. This contrasts our earlier findings obtained in rats with experimentally induced hypoarousal, where abnormal attack patterns were associated with over-activated central amygdala, lateral hypothalamus, and ventrolateral periaqueductal gray that are believed to control predatory attacks. We have observed no similar activation patterns in rats socially isolated from weaning. In summary, these findings suggest that despite some phenotypic similarities, the neuronal background of hypo and hyperarousal-associated abnormal forms of aggression are markedly different. While the neuronal activation patterns induced by normal rivalry and hypoarousal-driven aggression are qualitative different, hyperarousal-associated aggression appears to be an exaggerated form of rivalry aggression.

  14. Sonic hedgehog and retinoic Acid induce bone marrow-derived stem cells to differentiate into glutamatergic neural cells.

    Science.gov (United States)

    Yu, Zhenhai; Wu, Shixing; Liu, Zhen; Lin, Haiyan; Chen, Lei; Yuan, Xinli; Zhang, Zhiying; Liu, Fang; Zhang, Chuansen

    2015-01-01

    Studies have showed that transplanted stem cells in the inner ear won't regenerate to replace the damaged sensory hair cells. They can spontaneously differentiate into mesenchymal cells and fibrocytes in the damaged inner ear. Only mature sensory cells of MSCs-derived possess the great potency for cell transplantation in the treatment of sensorineural hearing loss. So, we try to establish an efficient generation of the glutamatergic sensory neural phenotype for the cell transplantation of the hearing loss. We isolated MSCs from femoral and tibial bones according to their adherence to culture dishes. After purification, proliferation, and passaged, cells became homogeneous in appearance, showing more uniformity and grew in a monolayer with a typical spindle-shape morphology. The cell surface markers were assessed using FACS to characterize the isolated cells. For neural induction to harvest the glutamatergic sensory neurons, passage 3 MSCs were incubated with preinduced medium for 24 hr, and neural-induced medium for an additional 14 days. The cells exhibit a typical neural shape. RT-PCR analysis indicated that the mRNA levels of the neural cell marker nestin, Tau, MAP-2, β-tubulin III, GluR-3, and GluR-4 were higher compared with primary MSCs. Immunohistochemistry and western-blotting proofed that nestin, MAP-2, β-tubulin III, and GluR-4 proteins indeed exhibit their expression difference in the induced cells compared to the MSCs. We show an efficient protocol by the combined applications of Sonic Hedgehog (Shh) and Retinoic Acid (RA) to induce MSCs to differentiate into the glutamatergic sensory neuron which were identified from the morphological, biochemical, and molecular characteristics.

  15. [Plant lectins and embryonic tissue factors as probes for studying the mechanisms of neural induction in amphibians].

    Science.gov (United States)

    Mikhaĭlov, A T; Gorgoliuk, N A

    1992-01-01

    Using various experimental techniques, we have demonstrated that animal pole ectoderm (APE) of Rana temporaria embryos at the stage of early gastrula is a good target tissue for testing the neuralizing (N) factors. In this respect R. temporaria APE is comparable with APE of some other amphibian species. We found that concanavalin A (con A), phytohemagglutinin (PHA) and embryonic brain-derived neuralizing factor (EBDNF; a factor extracted from the chick embryonic brain and partially purified) have a pronounced N-effect on the APE of R. temporaria. In order to analyse possible mechanisms of N-action of these factors, we have cultured APE explants for 3 or 18 h in the medium containing various concentrations of con A, PHA of EBDNF. All these factors could produce neuralization in 50% explants. However, the optimal concentration and time of exposure were different. This is an evidence for different mechanisms of reception and transmission of a N-signal in each particular case. It appears that the APE consists of several cell subpopulations which differ in their threshold sensitivity to the N-effect of studied agents.

  16. Selective influence of Sox2 on POU transcription factor binding in embryonic and neural stem cells.

    Science.gov (United States)

    Mistri, Tapan Kumar; Devasia, Arun George; Chu, Lee Thean; Ng, Wei Ping; Halbritter, Florian; Colby, Douglas; Martynoga, Ben; Tomlinson, Simon R; Chambers, Ian; Robson, Paul; Wohland, Thorsten

    2015-09-01

    Embryonic stem cell (ESC) identity is orchestrated by co-operativity between the transcription factors (TFs) Sox2 and the class V POU-TF Oct4 at composite Sox/Oct motifs. Neural stem cells (NSCs) lack Oct4 but express Sox2 and class III POU-TFs Oct6, Brn1 and Brn2. This raises the question of how Sox2 interacts with POU-TFs to transcriptionally specify ESCs versus NSCs. Here, we show that Oct4 alone binds the Sox/Oct motif and the octamer-containing palindromic MORE equally well. Sox2 binding selectively increases the affinity of Oct4 for the Sox/Oct motif. In contrast, Oct6 binds preferentially to MORE and is unaffected by Sox2. ChIP-Seq in NSCs shows the MORE to be the most enriched motif for class III POU-TFs, including MORE subtypes, and that the Sox/Oct motif is not enriched. These results suggest that in NSCs, co-operativity between Sox2 and class III POU-TFs may not occur and that POU-TF-driven transcription uses predominantly the MORE cis architecture. Thus, distinct interactions between Sox2 and POU-TF subclasses distinguish pluripotent ESCs from multipotent NSCs, providing molecular insight into how Oct4 alone can convert NSCs to pluripotency.

  17. Social inference deficits in temporal lobe epilepsy and lobectomy: risk factors and neural substrates.

    Science.gov (United States)

    Cohn, Melanie; St-Laurent, Marie; Barnett, Alexander; McAndrews, Mary Pat

    2015-05-01

    In temporal lobe epilepsy and lobectomy, deficits in emotion identification have been found consistently, but there is limited evidence for complex social inference skills such as theory of mind. Furthermore, risk factors and the specific neural underpinnings of these deficits in this population are unclear. We investigated these issues using a comprehensive range of social inference tasks (emotion identification and comprehension of sincere, deceitful and sarcastic social exchanges) in individuals with temporal lobe epilepsy or lobectomy (n = 87). We observed deficits across patient groups which were partly related to the presence of mesial temporal lobe sclerosis, early age of seizure onset and left lobectomy. A voxel-based morphometry analysis conducted in the pre-operative group confirmed the importance of the temporal lobe by showing a relationship between left hippocampal atrophy and overall social inference abilities, and between left anterior neocortex atrophy and sarcasm comprehension. These findings are in keeping with theoretical proposals that the hippocampus is critical for binding diverse elements in cognitive domains beyond canonical episodic memory operations, and that the anterior temporal cortex is a convergence zone of higher-order perceptual and emotional processes, and of stored representations. As impairments were frequent, we require further investigation of this behavioural domain and its impact on the lives of people with epilepsy.

  18. Topographic factor analysis: a Bayesian model for inferring brain networks from neural data.

    Directory of Open Access Journals (Sweden)

    Jeremy R Manning

    Full Text Available The neural patterns recorded during a neuroscientific experiment reflect complex interactions between many brain regions, each comprising millions of neurons. However, the measurements themselves are typically abstracted from that underlying structure. For example, functional magnetic resonance imaging (fMRI datasets comprise a time series of three-dimensional images, where each voxel in an image (roughly reflects the activity of the brain structure(s-located at the corresponding point in space-at the time the image was collected. FMRI data often exhibit strong spatial correlations, whereby nearby voxels behave similarly over time as the underlying brain structure modulates its activity. Here we develop topographic factor analysis (TFA, a technique that exploits spatial correlations in fMRI data to recover the underlying structure that the images reflect. Specifically, TFA casts each brain image as a weighted sum of spatial functions. The parameters of those spatial functions, which may be learned by applying TFA to an fMRI dataset, reveal the locations and sizes of the brain structures activated while the data were collected, as well as the interactions between those structures.

  19. Connecting teratogen-induced congenital heart defects to neural crest cells and their effect on cardiac function.

    Science.gov (United States)

    Karunamuni, Ganga H; Ma, Pei; Gu, Shi; Rollins, Andrew M; Jenkins, Michael W; Watanabe, Michiko

    2014-09-01

    Neural crest cells play many key roles in embryonic development, as demonstrated by the abnormalities that result from their specific absence or dysfunction. Unfortunately, these key cells are particularly sensitive to abnormalities in various intrinsic and extrinsic factors, such as genetic deletions or ethanol-exposure that lead to morbidity and mortality for organisms. This review discusses the role identified for a segment of neural crest in regulating the morphogenesis of the heart and associated great vessels. The paradox is that their derivatives constitute a small proportion of cells to the cardiovascular system. Findings supporting that these cells impact early cardiac function raises the interesting possibility that they indirectly control cardiovascular development at least partially through regulating function. Making connections between insults to the neural crest, cardiac function, and morphogenesis is more approachable with technological advances. Expanding our understanding of early functional consequences could be useful in improving diagnosis and testing therapies.

  20. Neural correlates underlying naloxone-induced amelioration of sexual behavior deterioration due to an alarm pheromone

    Directory of Open Access Journals (Sweden)

    Tatsuya eKobayashi

    2015-02-01

    Full Text Available Sexual behavior is suppressed by various types of stressors. We previously demonstrated that an alarm pheromone released by stressed male Wistar rats is a stressor to other rats, increases the number of mounts needed for ejaculation, and decreases the hit rate (described as the number of intromissions/sum of the mounts and intromissions. This deterioration in sexual behavior was ameliorated by pretreatment with the opioid receptor antagonist naloxone. However, the neural mechanism underlying this remains to be elucidated. Here, we examined Fos expression in 31 brain regions of pheromone-exposed rats and naloxone-pretreated pheromone-exposed rats 60 min after 10 intromissions. As previously reported, the alarm pheromone increased the number of mounts and decreased the hit rate. In addition, Fos expression was increases in the anterior medial division, anterior lateral division and posterior division of the bed nucleus of the stria terminalis, parvocellular part of the paraventricular nucleus of the hypothalamus, arcuate nucleus, dorsolateral and ventrolateral periaqueductal gray, and nucleus paragigantocellularis. Fos expression decreased in the magnocellular part of the paraventricular nucleus of the hypothalamus. Pretreatment with naloxone blocked the pheromone-induced changes in Fos expression in the magnocellular part of the paraventricular nucleus of the hypothalamus, ventrolateral periaqueductal gray, and nucleus paragigantocellularis. Based on these results, we hypothesize that the alarm pheromone deteriorated sexual behavior by activating the ventrolateral periaqueductal gray-nucleus paragigantocellularis cluster and suppressing the magnocellular part of the paraventricular nucleus of the hypothalamus via the opioidergic pathway.

  1. Marmoset induced pluripotent stem cells: Robust neural differentiation following pretreatment with dimethyl sulfoxide

    Directory of Open Access Journals (Sweden)

    Zhifang Qiu

    2015-07-01

    Full Text Available The marmoset is an important nonhuman primate model for regenerative medicine. For experimental autologous cell therapy based on induced pluripotent (iPS cells in the marmoset, cells must be able to undergo robust and reliable directed differentiation that will not require customization for each specific iPS cell clone. When marmoset iPS cells were aggregated in a hanging drop format for 3 days, followed by exposure to dual SMAD inhibitors and retinoic acid in monolayer culture for 3 days, we found substantial variability in the response of different iPS cell clones. However, when clones were pretreated with 0.05–2% dimethyl sulfoxide (DMSO for 24 hours, all clones showed a very similar maximal response to the directed differentiation scheme. Peak responses were observed at 0.5% DMSO in two clones and at 1% DMSO in a third clone. When patterns of gene expression were examined by microarray analysis, hierarchical clustering showed very similar responses in all 3 clones when they were pretreated with optimal DMSO concentrations. The change in phenotype following exposure to DMSO and the 6 day hanging drop/monolayer treatment was confirmed by immunocytochemistry. Analysis of DNA content in DMSO-exposed cells indicated that it is unlikely that DMSO acts by causing cells to exit from the cell cycle. This approach should be generally valuable in the directed neural differentiation of pluripotent cells for experimental cell therapy.

  2. Rapid identification and discrimination of bacterial strains by laser induced breakdown spectroscopy and neural networks.

    Science.gov (United States)

    Manzoor, S; Moncayo, S; Navarro-Villoslada, F; Ayala, J A; Izquierdo-Hornillos, R; de Villena, F J Manuel; Caceres, J O

    2014-04-01

    Identification and discrimination of bacterial strains of same species exhibiting resistance to antibiotics using laser induced breakdown spectroscopy (LIBS) and neural networks (NN) algorithm is reported. The method has been applied to identify 40 bacterial strains causing hospital acquired infections (HAI), i.e. Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, Salmonella pullurum and Salmonella salamae. The strains analyzed included both isolated from clinical samples and constructed in laboratory that differ in mutations as a result of their resistance to one or more antibiotics. Small changes in the atomic composition of the bacterial strains, as a result of their mutations and genetic variations, were detected by the LIBS-NN methodology and led to their identification and classification. This is of utmost importance because solely identification of bacterial species is not sufficient for disease diagnosis and identification of the actual strain is also required. The proposed method was successfully able to discriminate strains of the same bacterial species. The optimized NN models provided reliable bacterial strain identification with an index of spectral correlation higher than 95% for the samples analyzed, showing the potential and effectiveness of the method to address the safety and social-cost HAI-related issue. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Neural progenitor cells from human induced pluripotent stem cells generated less autogenous immune response.

    Science.gov (United States)

    Huang, Ke; Liu, PengFei; Li, Xiang; Chen, ShuBin; Wang, LiHui; Qin, Li; Su, ZhengHui; Huang, WenHao; Liu, Juli; Jia, Bei; Liu, Jie; Cai, JingLei; Pei, DuanQing; Pan, GuangJin

    2014-02-01

    The breakthrough development of induced pluripotent stem cells (iPSCs) raises the prospect of patient-specific treatment for many diseases through the replacement of affected cells. However, whether iPSC-derived functional cell lineages generate a deleterious immune response upon auto-transplantation remains unclear. In this study, we differentiated five human iPSC lines from skin fibroblasts and urine cells into neural progenitor cells (NPCs) and analyzed their immunogenicity. Through co-culture with autogenous peripheral blood mononuclear cells (PBMCs), we showed that both somatic cells and iPSC-derived NPCs do not stimulate significant autogenous PBMC proliferation. However, a significant immune reaction was detected when these cells were co-cultured with allogenous PBMCs. Furthermore, no significant expression of perforin or granzyme B was detected following stimulation of autogenous immune effector cells (CD3(+)CD8(-) T cells, CD3(+)CD8(+) T cells or CD3(-)CD56(+) NK cells) by NPCs in both PBMC and T cell co-culture systems. These results suggest that human iPSC-derived NPCs may not initiate an immune response in autogenous transplants, and thus set a base for further preclinical evaluation of human iPSCs.

  4. Expandable and Rapidly Differentiating Human Induced Neural Stem Cell Lines for Multiple Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Dana M. Cairns

    2016-09-01

    Full Text Available Limited availability of human neurons poses a significant barrier to progress in biological and preclinical studies of the human nervous system. Current stem cell-based approaches of neuron generation are still hindered by prolonged culture requirements, protocol complexity, and variability in neuronal differentiation. Here we establish stable human induced neural stem cell (hiNSC lines through the direct reprogramming of neonatal fibroblasts and adult adipose-derived stem cells. These hiNSCs can be passaged indefinitely and cryopreserved as colonies. Independently of media composition, hiNSCs robustly differentiate into TUJ1-positive neurons within 4 days, making them ideal for innervated co-cultures. In vivo, hiNSCs migrate, engraft, and contribute to both central and peripheral nervous systems. Lastly, we demonstrate utility of hiNSCs in a 3D human brain model. This method provides a valuable interdisciplinary tool that could be used to develop drug screening applications as well as patient-specific disease models related to disorders of innervation and the brain.

  5. Carbon Ion Irradiated Neural Injury Induced the Peripheral Immune Effects in Vitro or in Vivo

    Directory of Open Access Journals (Sweden)

    Runhong Lei

    2015-11-01

    Full Text Available Carbon ion radiation is a promising treatment for brain cancer; however, the immune system involved long-term systemic effects evoke a concern of complementary and alternative therapies in clinical treatment. To clarify radiotherapy caused fundamental changes in peripheral immune system, examinations were performed based on established models in vitro and in vivo. We found that brain-localized carbon ion radiation of neural cells induced complex changes in the peripheral blood, thymus, and spleen at one, two, and three months after its application. Atrophy, apoptosis, and abnormal T-cell distributions were observed in rats receiving a single high dose of radiation. Radiation downregulated the expression of proteins involved in T-cell development at the transcriptional level and increased the proportion of CD3+CD4−CD8+ T-cells in the thymus and the proportion of CD3+CD4+CD8− T-cells in the spleen. These data show that brain irradiation severely affects the peripheral immune system, even at relatively long times after irradiation. In addition, they provide valuable information that will implement the design of biological-based strategies that will aid brain cancer patients suffering from the long-term side effects of radiation.

  6. Transplantation of placenta-derived mesenchymal stem cell-induced neural stem cells to treat spinal cord injur y

    Institute of Scientific and Technical Information of China (English)

    Zhi Li; Wei Zhao; Wei Liu; Ye Zhou; Jingqiao Jia; Lifeng Yang

    2014-01-01

    Because of their strong proliferative capacity and multi-potency, placenta-derived mesenchymal stem cells have gained interest as a cell source in the ifeld of nerve damage repair. In the present study, human placenta-derived mesenchymal stem cells were induced to differentiate into neural stem cells, which were then transplanted into the spinal cord after local spinal cord injury in rats. The motor functional recovery and pathological changes in the injured spinal cord were observed for 3 successive weeks. The results showed that human placenta-derived mesenchymal stem cells can differentiate into neuron-like cells and that induced neural stem cells contribute to the resto-ration of injured spinal cord without causing transplant rejection. Thus, these cells promote the recovery of motor and sensory functions in a rat model of spinal cord injury. Therefore, human placenta-derived mesenchymal stem cells may be useful as seed cells during the repair of spinal cord injury.

  7. Life stage-related differences in susceptibility to acrylamide-induced neural and testicular toxicity.

    Science.gov (United States)

    Takahashi, Miwa; Inoue, Kaoru; Koyama, Naoki; Yoshida, Midori; Irie, Kaoru; Morikawa, Tomomi; Shibutani, Makoto; Honma, Masamitsu; Nishikawa, Akiyoshi

    2011-09-01

    In order to assess age-dependence of susceptibility to acrylamide (ACR)-induced neural and testicular toxicity, 3- and 7-week-old male SD rats were given ACR at 0, 50, 100, or 200 ppm in the drinking water for 4 weeks, and the nervous and male reproductive systems were examined histopathologically. Testicular genotoxicity was evaluated with the comet assay and the micronucleus (MN) test. Glutathione S-transferase (GST) activity and glutathione (GSH) content in the liver and testis were also measured. In both young and adult animals, neurotoxicity was evident from 100 ppm and increased in proportion to ACR intake per body weight. In the testis, marked degeneration and exfoliation, mainly of spermatids, were observed from 100 ppm limited to young animals. The comet assay revealed ACR to significantly induce DNA damage from 100 ppm in both life stages, while MNs were found only in young rats from 100 ppm. The level of GST activity in the testis of young rats at the end of experiment was significantly lower than that of adult animals, regardless of the ACR treatment. There were no life stage-related differences in GSH contents in the liver and testis. These results suggest that susceptibility to neurotoxicity might not differ between young and adult rats when exposure levels are adjusted for body weight. Regarding testicular toxicity, young animals around puberty proved more susceptible than adult animals, possibly due to their lower level of testicular GST activity than that in adult animals.

  8. Neural regulation of the kidney function in rats with cisplatin induced renal failure

    Directory of Open Access Journals (Sweden)

    Niamh E Goulding

    2015-06-01

    Full Text Available Aim: Chronic kidney disease (CKD is often associated with a disturbed cardiovascular homeostasis. This investigation explored the role of the renal innervation in mediating deranged baroreflex control of renal sympathetic nerve activity (RSNA and renal excretory function in cisplatin-induced renal failure.Methods: Rats were either intact or bilaterally renally denervated four days prior to receiving cisplatin (5mg/kg i.p. and entered a chronic metabolic study for 8 days. At day 8, other groups of rats were prepared for acute measurement of RSNA or renal function with either intact or denervated kidneys.Results: Following the cisplatin challenge, creatinine clearance was 50% lower while fractional sodium excretion and renal cortical and medullary TGF-β1 concentrations were 3-4 fold higher in both intact and renally denervated rats compared to control rats. In cisplatin-treated rats, the maximal gain of the high-pressure baroreflex curve was only 20% that of control rats, but not different from that of renally denervated control rats. Volume expansion reduced RSNA by 50% in control and in cisplatin-treated rats but only following bilateral renal denervation. The volume expansion mediated natriuresis/diuresis was absent in the cisplatin-treated rats but was normalised following renal denervation. Conclusions: Cisplatin-induced renal injury impaired renal function and caused a sympatho-excitation with blunting of high and low pressure baroreflex regulation of RSNA, which was dependent on the renal innervation. It is suggested that in man with CKD there is a dysregulation of the neural control of the kidney mediated by its sensory innervation.

  9. High sugar-induced insulin resistance in Drosophila relies on the lipocalin Neural Lazarillo.

    Directory of Open Access Journals (Sweden)

    Matthieu Y Pasco

    Full Text Available In multicellular organisms, insulin/IGF signaling (IIS plays a central role in matching energy needs with uptake and storage, participating in functions as diverse as metabolic homeostasis, growth, reproduction and ageing. In mammals, this pleiotropy of action relies in part on a dichotomy of action of insulin, IGF-I and their respective membrane-bound receptors. In organisms with simpler IIS, this functional separation is questionable. In Drosophila IIS consists of several insulin-like peptides called Dilps, activating a unique membrane receptor and its downstream signaling cascade. During larval development, IIS is involved in metabolic homeostasis and growth. We have used feeding conditions (high sugar diet, HSD that induce an important change in metabolic homeostasis to monitor possible effects on growth. Unexpectedly we observed that HSD-fed animals exhibited severe growth inhibition as a consequence of peripheral Dilp resistance. Dilp-resistant animals present several metabolic disorders similar to those observed in type II diabetes (T2D patients. By exploring the molecular mechanisms involved in Drosophila Dilp resistance, we found a major role for the lipocalin Neural Lazarillo (NLaz, a target of JNK signaling. NLaz expression is strongly increased upon HSD and animals heterozygous for an NLaz null mutation are fully protected from HSD-induced Dilp resistance. NLaz is a secreted protein homologous to the Retinol-Binding Protein 4 involved in the onset of T2D in human and mice. These results indicate that insulin resistance shares common molecular mechanisms in flies and human and that Drosophila could emerge as a powerful genetic system to study some aspects of this complex syndrome.

  10. High sugar-induced insulin resistance in Drosophila relies on the lipocalin Neural Lazarillo.

    Science.gov (United States)

    Pasco, Matthieu Y; Léopold, Pierre

    2012-01-01

    In multicellular organisms, insulin/IGF signaling (IIS) plays a central role in matching energy needs with uptake and storage, participating in functions as diverse as metabolic homeostasis, growth, reproduction and ageing. In mammals, this pleiotropy of action relies in part on a dichotomy of action of insulin, IGF-I and their respective membrane-bound receptors. In organisms with simpler IIS, this functional separation is questionable. In Drosophila IIS consists of several insulin-like peptides called Dilps, activating a unique membrane receptor and its downstream signaling cascade. During larval development, IIS is involved in metabolic homeostasis and growth. We have used feeding conditions (high sugar diet, HSD) that induce an important change in metabolic homeostasis to monitor possible effects on growth. Unexpectedly we observed that HSD-fed animals exhibited severe growth inhibition as a consequence of peripheral Dilp resistance. Dilp-resistant animals present several metabolic disorders similar to those observed in type II diabetes (T2D) patients. By exploring the molecular mechanisms involved in Drosophila Dilp resistance, we found a major role for the lipocalin Neural Lazarillo (NLaz), a target of JNK signaling. NLaz expression is strongly increased upon HSD and animals heterozygous for an NLaz null mutation are fully protected from HSD-induced Dilp resistance. NLaz is a secreted protein homologous to the Retinol-Binding Protein 4 involved in the onset of T2D in human and mice. These results indicate that insulin resistance shares common molecular mechanisms in flies and human and that Drosophila could emerge as a powerful genetic system to study some aspects of this complex syndrome.

  11. Distribution and localization of fibroblast growth factor-8 in rat brain and nerve cells during neural stem/progenitor cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Jiang Lu; Dongsheng Li; Kehuan Lu

    2012-01-01

    The present study explored the distribution and localization of fibroblast growth factor-8 and its potential receptor,fibroblast growth factor receptor-3,in adult rat brain in vivo and in nerve cells during differentiation of neural stem/progenitor cells in vitro.Immunohistochemistry was used to examine the distribution of fibroblast growth factor-8 in adult rat brain in vivo.Localization of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in cells during neural stem/progenitor cell differentiation in vitro was detected by immunofluorescence.Flow cytometry and immunofluorescence were used to evaluate the effect of an anti-fibroblast growth factor-8 antibody on neural stem/progenitor cell differentiation and expansion in vitro.Results from this study confirmed that fibroblast growth factor-8 was mainly distributed in adult midbrain,namely the substantia nigra,compact part,dorsal tier,substantia nigra and reticular part,but was not detected in the forebrain comprising the caudate putamen and striatum.Unusual results were obtained in retrosplenial locations of adult rat brain.We found that fibroblast growth factor-8 and fibroblast growth factor receptor-3 were distributed on the cell membrane and in the cytoplasm of nerve cells using immunohistochemistry and immunofluorescence analyses.We considered that the distribution of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in neural cells corresponded to the characteristics of fibroblast growth factor-8,a secretory factor.Addition of an anti-fibroblast growth factor-8 antibody to cultures significantly affected the rate of expansion and differentiation of neural stem/progenitor cells.In contrast,addition of recombinant fibroblast growth factor-8 to differentiation medium promoted neural stem/progenitor cell differentiation and increased the final yields of dopaminergic neurons and total neurons.Our study may help delineate the important roles of fibroblast growth factor-8 in brain

  12. Changes in the osmolarity of the embryonic microenvironment induce neural tube defects.

    Science.gov (United States)

    Jin, Yi-Mei; Wang, Guang; Zhang, Nuan; Wei, Yi-Fan; Li, Shuai; Chen, You-Peng; Chuai, Manli; Lee, Henry Siu Sum; Hocher, Berthold; Yang, Xuesong

    2015-05-01

    Many maternal disorders that modify the embryonic microenvironment, such as a change in osmolarity, can affect development, but how these changes influence the early embryo remains obscure. Neural tube defects, for example, are common congenital disorders found in fetus and neonates. In this study, we investigated the impact of anisotonic osmolarity (unequal osmotic pressures) on neural tube development in the early chick embryo, finding that neuronal cell differentiation was impaired in the neural tube due to enhanced apoptosis and repressed cell proliferation. Anisotonic osmolarity also affected normal development of the neural crest, which in turn influenced abnormal development of the neural tube. As neural tube development is highly dependent on the proper expression of bone morphogenetic protein 4 (BMP4), paired box 7 (PAX7), and sonic hedgehog (SHH) genes in the dorsal and ventral regions along the tube, we investigated the impact of anisotonic osmolarity on their expression. Indeed, small changes in osmolarity could positively and negatively impact the expression of these regulatory genes, which profoundly affected neural tube development. Thus, both the central and peripheral nervous systems were perturbed by anisotonic consitions as a consequence of the abnormal expression of key genes within the developing neural tube.

  13. Effects of Some Neurobiological Factors in a Self-organized Critical Model Based on Neural Networks

    Institute of Scientific and Technical Information of China (English)

    ZHOU Li-Ming; ZHANG Ying-Yue; CHEN Tian-Lun

    2005-01-01

    Based on an integrate-and-fire mechanism, we investigate the effect of changing the efficacy of the synapse,the transmitting time-delayed, and the relative refractoryperiod on the self-organized criticality in our neural network model.

  14. Cloning of the Eukaryotic Expression Vector with Nerve Growth Factor in Rats and Its Effects on Proliferation and Differentiation of Mesencephal Neural Stem Cells of Fetal Rats

    Institute of Scientific and Technical Information of China (English)

    Minhua LIN; Lin YANG; Rong FU; Hongyang ZHAO

    2008-01-01

    Summary: The eukaryotic expression vector containing full-length cDNA sequence of rate nerve growth factor (NGF) β subunit was constructed and its effects on proliferation and differentiation of neural stem cells were observed. By using PCR, full-length cDNA sequence of NGF β subunit in rats was cloned and ligated into the eukaryotic expression vector pEGFP-N1-NGE The recombinant plasmid pEGFP-N1-NGF was transfected into the mesencephal neural stem cells of embryonic rats by Lipofectamin and transiently expressed. MTT method was used to determine the effects of NGF on proliferation of neural stem cells, and under phase-contrast microscopy, the effects of NGF on growth of nervous processes following differentiation of neural stem cells were observed. Sequence analysis indicated that the cloned full-length cDNA sequence of rat NGF β was identical to that of published sequence encoding NGF in gene GeneBank. The transfection of recombinant plasmid pEGFP-N1-NGF into mesencephal neural stem cells of embryonic rats could obviously promote proliferation of neural stem cells and faciliate the growth of neural stem cells-derived nerve cells. It was suggested that neural stem cells could be used as a vehicle of gene transfer, and the expression of NGF β subunit in the neural stem cells could promote the growth of nerve cells derived from neural stem cells.

  15. Inflammation-induced miRNA-155 inhibits self-renewal of neural stem cells via suppression of CCAAT/enhancer binding protein β (C/EBPβ) expression

    Science.gov (United States)

    Obora, Kayoko; Onodera, Yuta; Takehara, Toshiyuki; Frampton, John; Hasei, Joe; Ozaki, Toshifumi; Teramura, Takeshi; Fukuda, Kanji

    2017-01-01

    Intracerebral inflammation resulting from injury or disease is implicated in disruption of neural regeneration and may lead to irreversible neuronal dysfunction. Analysis of inflammation-related microRNA profiles in various tissues, including the brain, has identified miR-155 among the most prominent miRNAs linked to inflammation. Here, we hypothesize that miR-155 mediates inflammation-induced suppression of neural stem cell (NSC) self-renewal. Using primary mouse NSCs and human NSCs derived from induced pluripotent stem (iPS) cells, we demonstrate that three important genes involved in NSC self-renewal (Msi1, Hes1 and Bmi1) are suppressed by miR-155. We also demonstrate that suppression of self-renewal genes is mediated by the common transcription factor C/EBPβ, which is a direct target of miR-155. Our study describes an axis linking inflammation and miR-155 to expression of genes related to NSC self-renewal, suggesting that regulation of miR-155 may hold potential as a novel therapeutic strategy for treating neuroinflammatory diseases. PMID:28240738

  16. The effects of GM1 and Bfgf synergistically inducing adult rat bone marrow stromal cells to form neural progenitor cells and their differentiation

    Institute of Scientific and Technical Information of China (English)

    张卉; 王纪佐; 孙红宇; 张建宁; 杨树源

    2004-01-01

    Objective: To investigate the effects of GM1 on inducing adult rat bone marrow stromal cells(MSCs) to form neural progenitor cells and their differentiation. Methods: Purified MSCs were induced by different components of basic fibroblast growth factor (bFGF) alone, GM1 alone or combination of bFGF with GM1. After 3 days' incubation, fibronectin and collagen I were detected with immunocytochemistry, and nestin was detected with immunofluorescence. Neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP) and galactose cerebroside (GalC) were detected with immunocytochemistry after 7 days' incubation. Results: After induction with bFGF alone or combination of bFGF and GM1, some MSCs exhibited the phenotypes of neural progenitor cells, and then neurons and astrocytes. In these two groups, the positive cells for fibronectin and collagen I decreased markedly after 3 days' induction. At the same time, the positive cells for nestin increased markedly. After 7 days' induction, NSE and GFAP-positive cells increased significantly. Furthermore, the addition of bFGF and GM1 caused the maximal variation. However, addition of GM1 alone had no inductive effects.Conclusions: Combination of bFGF with GM1 may synergistically promote the transformation of MSCs and differentiation into neurons and astrocyte-like cells. The results suggest a promising route for the application of MSCs.

  17. Frecuencia y algunos factores de riesgo de mortalidad en el estado de Hidalgo, México, por defectos de cierre del tubo neural Mortality due to neural tube defects and risk factors in Hidalgo, Mexico

    Directory of Open Access Journals (Sweden)

    Sergio Muñoz-Juárez

    2002-09-01

    Full Text Available Objetivo. Calcular el riesgo de muerte fetal secundaria a defectos del cierre del tubo neural y estimar factores asociados con este tipo de muertes en el estado de Hidalgo. Material y métodos. La información analizada en el año 2000 fue obtenida de los certificados de muerte fetal del periodo 1990-1995 en el estado de Hidalgo. Se utilizó un diseño de mortalidad proporcional, considerado como una variante del diseño de casos y controles. Los casos fueron aquellas muertes fetales secundarias a defectos del tubo neural y los controles las muertes fetales por otros motivos. Se utilizó ji cuadrada de Pearson para estimar las diferencias entre los casos y controles. Para el riesgo crudo de morir por defectos de cierre del tubo neural se empleó la razón de momios, y para el riesgo ajustado se usó la regresión logística no condicional. Resultados. Se analizaron 3 673 certificados de muerte fetal, identificándose 8.06% de muertes por defectos del tubo neural; el resto lo constituyeron muertes por otras causas. Se encontró como variables asociadas con la muerte fetal por defectos del tubo neural a los fetos que pesaron menos de 2 500 gramos (RM 5.0, IC 95% 3.6, 6.7, a los productos del sexo femenino (RM 1.7, IC 95% 1.3, 2.3 y a las muertes ocurridas en el periodo fetal tardío (RM 5.5 IC 95% 3.8, 8.1. Conclusiones. Los resultados indican que el riesgo de muerte fetal debida a defectos del tubo neural es mayor en productos de bajo peso, en los del sexo femenino y los que ocurren en el periodo fetal tardío.Objective. To calculate the risk of fetal death due to neural tube defects and estimate associated factors in the state of Hidalgo, Mexico. Material and Methods. Data were abstracted from death certificates registered during 1990-1995 in the state of Hidalgo, Mexico. The design was a proportional mortality study, which is considered as a variant of the case control design. Cases were deaths with any type of neural tube defect, and controls

  18. Apoptotic gene expression in the neural tube during early human embryonic development

    Institute of Scientific and Technical Information of China (English)

    Guifang Chen; Tiandong Li; Peipei Ding; Ping Yang; Xiao Zhang

    2011-01-01

    Neural tube development comprises neural induction,neural epithelial cell proliferation,and apoptosis,as well as migration of nerve cells.Too much or too little apoptosis leads to abnormal nervous system development.The present study analyzed expression and distribution of apoptotic-related factors,including Fas,FasL,and caspase-3,during human embryonic neural tube development.Experimental results showed that increased caspase-3 expression promoted neural apoptosis via a mitochondriai-mediated intrinsic pathway at 4 weeks during early human embryonic neural tube development.Subsequently,Fas and FasL expression increased during embryonic development.The results suggest that neural cells influence neural apoptosis through synergistic effects of extrinsic pathways.Therefore,neural apoptosis during the early period of neural tube development in the human embryo might be regulated by the death receptor induced apoptotic extrinsic pathways.

  19. Evaluation of common genetic variants in 82 candidate genes as risk factors for neural tube defects

    Directory of Open Access Journals (Sweden)

    Pangilinan Faith

    2012-08-01

    Full Text Available Abstract Background Neural tube defects (NTDs are common birth defects (~1 in 1000 pregnancies in the US and Europe that have complex origins, including environmental and genetic factors. A low level of maternal folate is one well-established risk factor, with maternal periconceptional folic acid supplementation reducing the occurrence of NTD pregnancies by 50-70%. Gene variants in the folate metabolic pathway (e.g., MTHFR rs1801133 (677 C > T and MTHFD1 rs2236225 (R653Q have been found to increase NTD risk. We hypothesized that variants in additional folate/B12 pathway genes contribute to NTD risk. Methods A tagSNP approach was used to screen common variation in 82 candidate genes selected from the folate/B12 pathway and NTD mouse models. We initially genotyped polymorphisms in 320 Irish triads (NTD cases and their parents, including 301 cases and 341 Irish controls to perform case–control and family based association tests. Significantly associated polymorphisms were genotyped in a secondary set of 250 families that included 229 cases and 658 controls. The combined results for 1441 SNPs were used in a joint analysis to test for case and maternal effects. Results Nearly 70 SNPs in 30 genes were found to be associated with NTDs at the p MFTC, CDKN2A, ADA, PEMT, CUBN, GART, DNMT3A, MTHFD1 and T (Brachyury and included the known NTD risk factor MTHFD1 R653Q (rs2236225. The single strongest signal was observed in a new candidate, MFTC rs17803441 (OR = 1.61 [1.23-2.08], p = 0.0003 for the minor allele. Though nominally significant, these associations did not remain significant after correction for multiple hypothesis testing. Conclusions To our knowledge, with respect to sample size and scope of evaluation of candidate polymorphisms, this is the largest NTD genetic association study reported to date. The scale of the study and the stringency of correction are likely to have contributed to real associations failing to survive

  20. Evaluation of common genetic variants in 82 candidate genes as risk factors for neural tube defects

    LENUS (Irish Health Repository)

    Pangilinan, Faith

    2012-08-02

    AbstractBackgroundNeural tube defects (NTDs) are common birth defects (~1 in 1000 pregnancies in the US and Europe) that have complex origins, including environmental and genetic factors. A low level of maternal folate is one well-established risk factor, with maternal periconceptional folic acid supplementation reducing the occurrence of NTD pregnancies by 50-70%. Gene variants in the folate metabolic pathway (e.g., MTHFR rs1801133 (677 C > T) and MTHFD1 rs2236225 (R653Q)) have been found to increase NTD risk. We hypothesized that variants in additional folate\\/B12 pathway genes contribute to NTD risk.MethodsA tagSNP approach was used to screen common variation in 82 candidate genes selected from the folate\\/B12 pathway and NTD mouse models. We initially genotyped polymorphisms in 320 Irish triads (NTD cases and their parents), including 301 cases and 341 Irish controls to perform case–control and family based association tests. Significantly associated polymorphisms were genotyped in a secondary set of 250 families that included 229 cases and 658 controls. The combined results for 1441 SNPs were used in a joint analysis to test for case and maternal effects.ResultsNearly 70 SNPs in 30 genes were found to be associated with NTDs at the p < 0.01 level. The ten strongest association signals (p-value range: 0.0003–0.0023) were found in nine genes (MFTC, CDKN2A, ADA, PEMT, CUBN, GART, DNMT3A, MTHFD1 and T (Brachyury)) and included the known NTD risk factor MTHFD1 R653Q (rs2236225). The single strongest signal was observed in a new candidate, MFTC rs17803441 (OR = 1.61 [1.23-2.08], p = 0.0003 for the minor allele). Though nominally significant, these associations did not remain significant after correction for multiple hypothesis testing.ConclusionsTo our knowledge, with respect to sample size and scope of evaluation of candidate polymorphisms, this is the largest NTD genetic association study reported to date. The scale of the study and the

  1. Rapid fluctuations in extracellular brain glucose levels induced by natural arousing stimuli and intravenous cocaine: fueling the brain during neural activation

    Science.gov (United States)

    Lenoir, Magalie

    2012-01-01

    Glucose, a primary energetic substrate for neural activity, is continuously influenced by two opposing forces that tend to either decrease its extracellular levels due to enhanced utilization in neural cells or increase its levels due to entry from peripheral circulation via enhanced cerebral blood flow. How this balance is maintained under physiological conditions and changed during neural activation remains unclear. To clarify this issue, enzyme-based glucose sensors coupled with high-speed amperometry were used in freely moving rats to evaluate fluctuations in extracellular glucose levels induced by brief audio stimulus, tail pinch (TP), social interaction with another rat (SI), and intravenous cocaine (1 mg/kg). Measurements were performed in nucleus accumbens (NAcc) and substantia nigra pars reticulata (SNr), which drastically differ in neuronal activity. In NAcc, where most cells are powerfully excited after salient stimulation, glucose levels rapidly (latency 2–6 s) increased (30–70 μM or 6–14% over baseline) by all stimuli; the increase differed in magnitude and duration for each stimulus. In SNr, where most cells are transiently inhibited by salient stimuli, TP, SI, and cocaine induced a biphasic glucose response, with the initial decrease (−20–40 μM or 5–10% below baseline) followed by a reboundlike increase. The critical role of neuronal activity in mediating the initial glucose response was confirmed by monitoring glucose currents after local microinjections of glutamate (GLU) or procaine (PRO). While intra-NAcc injection of GLU transiently increased glucose levels in this structure, intra-SNr PRO injection resulted in rapid, transient decreases in SNr glucose. Therefore, extracellular glucose levels in the brain change very rapidly after physiological and pharmacological stimulation, the response is structure specific, and the pattern of neuronal activity appears to be a critical factor determining direction and magnitude of physiological

  2. c-Myc Enhances Sonic Hedgehog-Induced Medulloblastoma Formation from Nestin-Expressing Neural Progenitors in Mice

    Directory of Open Access Journals (Sweden)

    Ganesh Rao

    2003-05-01

    Full Text Available Medulloblastomas are malignant brain tumors that arise in the cerebella of children. The presumed cellsof-origin are undifferentiated precursors of granule neurons that occupy the external granule layer (EGL of the developing cerebellum. The overexpression of proteins that normally stimulate proliferation of neural progenitor cells may initiate medulloblastoma formation. Two known mitogens for neural progenitors are the c-Myc oncoprotein and Sonic hedgehog (Shh, a crucial determinant of embryonic pattern formation in the central nervous system. We modeled the ability of c-Myc and Shh to induce medulloblastoma in mice using the RCAS/tv-a system, which allows postnatal gene transfer and expression in a cell type-specific manner. We targeted the expression of Shh and c-Myc to nestin-expressing neural progenitor cells by injecting replication-competent ALV splice acceptor (RCAS vectors into the cerebella of newborn mice. Following injection with RCAS-Shh alone, 3/32 (9% mice developed medulloblastomas and 5/32 showed multifocal hyperproliferation of the EGL, possibly a precursor stage of medulloblastoma. Following injection with RCAS-Shh plus RCAS-Myc, 9/39 (23% mice developed medulloblastomas. We conclude that nestin-expressing neural progenitors, present in the cerebellum at birth, can act as the cells-of-origin for medulloblastoma, and that c-Myc cooperates with Shh to enhance tumorigenicity.

  3. Conditioned Medium Derived from Neural Progenitor Cells Induces Long-term Post-ischemic Neuroprotection, Sustained Neurological Recovery, Neurogenesis, and Angiogenesis.

    Science.gov (United States)

    Doeppner, Thorsten R; Traut, Viktorija; Heidenreich, Alexander; Kaltwasser, Britta; Bosche, Bert; Bähr, Mathias; Hermann, Dirk M

    2017-03-01

    Adult neural progenitor cells (NPCs) induce post-ischemic long-term neuroprotection and brain remodeling by releasing of survival- and plasticity-promoting mediators. To evaluate whether secreted factors may mimic neuroprotective and restorative effects of NPCs, we exposed male C57BL6 mice to focal cerebral ischemia and intravenously applied conditioned medium (CM) derived from subventricular zone NPCs. CM dose-dependently reduced infarct volume and brain leukocyte infiltration after 48 h when delivered up to 12 h after focal cerebral ischemia. Neuroprotection persisted in the post-acute stroke phase yielding enhanced neurological recovery that lasted throughout the 28-day observation period. Increased Bcl-2, phosphorylated Akt and phosphorylated STAT-3 abundance, and reduced caspase-3 activity and Bax abundance were noted in ischemic brains of CM-treated mice at 48 h post-stroke, indicative of enhanced cell survival signaling. Long-term neuroprotection was associated with increased brain glial cell line-derived neurotrophic factor (GDNF) and vascular endothelial growth factor (VEGF) concentrations at 28 days resulting in increased neurogenesis and angiogenesis. The observation that NPC-derived CM induces sustained neuroprotection and neurological recovery suggests that cell transplantation may be dispensable when secreted factors are instead administered.

  4. Bioluminescence imaging of stroke-induced endogenous neural stem cell response.

    Science.gov (United States)

    Vandeputte, Caroline; Reumers, Veerle; Aelvoet, Sarah-Ann; Thiry, Irina; De Swaef, Sylvie; Van den Haute, Chris; Pascual-Brazo, Jesus; Farr, Tracy D; Vande Velde, Greetje; Hoehn, Mathias; Himmelreich, Uwe; Van Laere, Koen; Debyser, Zeger; Gijsbers, Rik; Baekelandt, Veerle

    2014-09-01

    Brain injury following stroke affects neurogenesis in the adult mammalian brain. However, a complete understanding of the origin and fate of the endogenous neural stem cells (eNSCs) in vivo is missing. Tools and technology that allow non-invasive imaging and tracking of eNSCs in living animals will help to overcome this hurdle. In this study, we aimed to monitor eNSCs in a photothrombotic (PT) stroke model using in vivo bioluminescence imaging (BLI). In a first strategy, inducible transgenic mice expressing firefly luciferase (Fluc) in the eNSCs were generated. In animals that received stroke, an increased BLI signal originating from the infarct region was observed. However, due to histological limitations, the identity and exact origin of cells contributing to the increased BLI signal could not be revealed. To overcome this limitation, we developed an alternative strategy employing stereotactic injection of conditional lentiviral vectors (Cre-Flex LVs) encoding Fluc and eGFP in the subventricular zone (SVZ) of Nestin-Cre transgenic mice, thereby specifically labeling the eNSCs. Upon induction of stroke, increased eNSC proliferation resulted in a significant increase in BLI signal between 2days and 2weeks after stroke, decreasing after 3months. Additionally, the BLI signal relocalized from the SVZ towards the infarct region during the 2weeks following stroke. Histological analysis at 90days post stroke showed that in the peri-infarct area, 36% of labeled eNSC progeny differentiated into astrocytes, while 21% differentiated into mature neurons. In conclusion, we developed and validated a novel imaging technique that unequivocally demonstrates that nestin(+) eNSCs originating from the SVZ respond to stroke injury by increased proliferation, migration towards the infarct region and differentiation into both astrocytes and neurons. In addition, this new approach allows non-invasive and specific monitoring of eNSCs over time, opening perspectives for preclinical

  5. Trichothecenes induce accumulation of glucosylceramide in neural cells by interfering with lactosylceramide synthase activity.

    Science.gov (United States)

    Kralj, Ana; Gurgui, Mihaela; König, Gabriele M; van Echten-Deckert, Gerhild

    2007-11-15

    Trichothecenes are sesquiterpenoid metabolites produced by several fungal strains that impair human and animal health. Since sphingolipids were connected with fungal toxicity the aim of the present study was to test the influence of fungal metabolites on sphingolipid metabolism in neural cells. The crude extract of fungal strain Spicellum roseum induced accumulation of glucosylceramide (GlcCer), and simultaneous reduction of the formation of lactosylceramide (LacCer) and complex gangliosides in primary cultured neurons. Following a bioassay-guided fractionation of the respective fungal extract we could demonstrate that the two isolated trichothecene derivatives, 8-deoxy-trichothecin (8-dT) and trichodermol (Td-ol) were responsible for this effect. Thus, incubation of primary cultured neurons as well as of neuroblastoma B104 cells for 24 h with 30 microM of either of the two fungal metabolites resulted in uncoupling of sphingolipid biosynthesis at the level of LacCer. For the observed reduction of LacCer synthase activity by about 90% cell integrity was crucial in both cell types. In neuroblastoma cells the amount of LacCer synthase mRNA was reduced in the presence of trichothecenes, whereas in primary cultured neurons this was not the case, suggesting a post-transcriptional mechanism of action in the latter cell type. The data also show that the compounds did not interfere with the translocation of GlcCer in neuroblastoma cells. Collectively, our results demonstrate that trichodermol and 8-deoxy-trichothecin inhibit LacCer synthase activity in a cell-type-specific manner.

  6. Induced Neural Stem Cells Achieve Long-Term Survival and Functional Integration in the Adult Mouse Brain

    Directory of Open Access Journals (Sweden)

    Kathrin Hemmer

    2014-09-01

    Full Text Available Differentiated cells can be converted directly into multipotent neural stem cells (i.e., induced neural stem cells [iNSCs]. iNSCs offer an attractive alternative to induced pluripotent stem cell (iPSC technology with regard to regenerative therapies. Here, we show an in vivo long-term analysis of transplanted iNSCs in the adult mouse brain. iNSCs showed sound in vivo long-term survival rates without graft overgrowths. The cells displayed a neural multilineage potential with a clear bias toward astrocytes and a permanent downregulation of progenitor and cell-cycle markers, indicating that iNSCs are not predisposed to tumor formation. Furthermore, the formation of synaptic connections as well as neuronal and glial electrophysiological properties demonstrated that differentiated iNSCs migrated, functionally integrated, and interacted with the existing neuronal circuitry. We conclude that iNSC long-term transplantation is a safe procedure; moreover, it might represent an interesting tool for future personalized regenerative applications.

  7. (GAGs) in normal and ethanol-induced chick embryo during neural ...

    African Journals Online (AJOL)

    Administrator

    2011-09-14

    Sep 14, 2011 ... NTDs are also associated with a number of other central nervous ... from the NT, while the same were reduced in 10% alcohol-administered embryos. In 15% alcohol- ... neural cell adhesion molecule (N-CAM), fibronectin,.

  8. Inducing and Aggravating Factors of Gastroesophageal Reflux Symptoms

    Directory of Open Access Journals (Sweden)

    Radhiyatam Mardhiyah

    2016-12-01

    Full Text Available Gastroesophageal reflux disease (subsequently abbreviated as GERD is a disease commonly found in the community. Several factors have been recognized as inducing and aggravating factors of GERD symptoms such as older age, female gender, obesity, smoking habit, alcohol consumption, certain diet and poor eating habit like eating fatty, spicy, and acid food.

  9. Molecular Analysis of Stromal Cells-Induced Neural Differentiation of Mouse Embryonic Stem Cells.

    Science.gov (United States)

    Joshi, Ramila; Buchanan, James Carlton; Paruchuri, Sailaja; Morris, Nathan; Tavana, Hossein

    2016-01-01

    Deriving specific neural cells from embryonic stem cells (ESCs) is a promising approach for cell replacement therapies of neurodegenerative diseases. When co-cultured with certain stromal cells, mouse ESCs (mESCs) differentiate efficiently to neural cells. In this study, a comprehensive gene and protein expression analysis of differentiating mESCs is performed over a two-week culture period to track temporal progression of cells from a pluripotent state to specific terminally-differentiated neural cells such as neurons, astrocytes, and oligodendrocytes. Expression levels of 26 genes consisting of marker genes for pluripotency, neural progenitors, and specific neuronal, astroglial, and oligodendrocytic cells are tracked using real time q-PCR. The time-course gene expression analysis of differentiating mESCs is combined with the hierarchal clustering and functional principal component analysis (FPCA) to elucidate the evolution of specific neural cells from mESCs at a molecular level. These statistical analyses identify three major gene clusters representing distinct phases of transition of stem cells from a pluripotent state to a terminally-differentiated neuronal or glial state. Temporal protein expression studies using immunohistochemistry demonstrate the generation of neural stem/progenitor cells and specific neural lineages and show a close agreement with the gene expression profiles of selected markers. Importantly, parallel gene and protein expression analysis elucidates long-term stability of certain proteins compared to those with a quick turnover. Describing the molecular regulation of neural cells commitment of mESCs due to stromal signaling will help identify major promoters of differentiation into specific cell types for use in cell replacement therapy applications.

  10. [Risk factors and subjective symptoms of drug-induced leucopenia].

    Science.gov (United States)

    Hayashi, Kyoko; Ohtsu, Fumiko; Yano, Reiko; Sakakibara, Jinsaku; Goto, Nobuyuki

    2011-01-01

    The present study investigated risk factors and subjective symptoms associated with drug-induced leucopenia. We selected 248 patients with drug-induced leucopenia from the Case Reports of Adverse Drug Reactions and Poisoning Information System (CARPIS) database of over 47000 case reports of adverse drug reactions and assigned them to a case group. We also randomly selected 743 cases of adverse drug reactions not associated with leucopenia as a control group. A comparison of patient characteristic data between the two groups using logistic-regression analysis revealed that female sex, autoimmune disease and renal damage were background risk factors for drug-induced leucopenia. In addition, thiamazole, ritodrine, propylthiouracil, ticlopidine, allopurinol, minocycline and captopril administration significantly increased the risk of drug-induced leucopenia. A significant association was also found for fever, chills and pharyngeal abnormalities. Based on these findings, we developed two estimated regression equations to help prevent drug-induced leucopenia in the community pharmacy setting.

  11. Role of glial cell line-derived neurotrophic factor (GDNF)-neural cell adhesion molecule (NCAM) interactions in induction of neurite outgrowth and identification of a binding site for NCAM in the heel region of GDNF

    DEFF Research Database (Denmark)

    Nielsen, Janne; Gotfryd, Kamil; Li, Shizhong

    2009-01-01

    The formation of appropriate neuronal circuits is an essential part of nervous system development and relies heavily on the outgrowth of axons and dendrites and their guidance to their respective targets. This process is governed by a large array of molecules, including glial cell line......-derived neurotrophic factor (GDNF) and the neural cell adhesion molecule (NCAM), the interaction of which induce neurite outgrowth. In the present study the requirements for NCAM-mediated GDNF-induced neurite outgrowth were investigated in cultures of hippocampal neurons, which do not express Ret. We demonstrate...

  12. Response of the sensorimotor cortex of cerebral palsy rats receiving transplantation of vascular endothelial growth factor 165-transfected neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Jielu Tan; Xiangrong Zheng; Shanshan Zhang; Yujia Yang; Xia Wang; Xiaohe Yu; Le Zhong

    2014-01-01

    Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge-nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into ifve groups: (1) sham operation (control), (2) cerebral palsy model alone or with (3) phosphate-buffered saline, (4) vascular en-dothelial growth factor 165 + neural stem cells, or (5) neural stem cells alone. hTe cerebral palsy model was established by ligating the letf common carotid artery followed by exposure to hypox-ia. Phosphate-buffered saline, vascular endothelial growth factor + neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. Atfer transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vas-cular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for ifnding water and the ifnding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. hTese ifndings indicate that the transplantation of vascu-lar endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deifcits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.

  13. Response of the sensorimotor cortex of cerebral palsy rats receiving transplantation of vascular endothelial growth factor 165-transfected neural stem cells.

    Science.gov (United States)

    Tan, Jielu; Zheng, Xiangrong; Zhang, Shanshan; Yang, Yujia; Wang, Xia; Yu, Xiaohe; Zhong, Le

    2014-10-01

    Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge-nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into five groups: (1) sham operation (control), (2) cerebral palsy model alone or with (3) phosphate-buffered saline, (4) vascular endothelial growth factor 165 + neural stem cells, or (5) neural stem cells alone. The cerebral palsy model was established by ligating the left common carotid artery followed by exposure to hypoxia. Phosphate-buffered saline, vascular endothelial growth factor + neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. After transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vascular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for finding water and the finding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. These findings indicate that the transplantation of vascular endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deficits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.

  14. Chronic gastritis rat model and role of inducing factors

    Institute of Scientific and Technical Information of China (English)

    Zun Xiang; Jian-Min Si; Huai-De Huang

    2004-01-01

    AIM: To establish an experimental animal model of chronic gastritis in a short term and to investigate the effects of several potential inflammation-inducing factors on rat gastric mucosa.METHODS: Twenty-four healthy, male SD rats were treated with intragastric administration of 600 mL/L alcohol, 20mmol/L sodium deoxycholate and 0.5 g/L ammonia (factor A), forage containing low levels of vitamins (factor B), and/or indomethacin (factor C), according to an L8(27)orthogonal design. After 12 wk, gastric antral and body mucosae were pathologically examined.RESULTS: Chronic gastritis model was successfully induced in rats treated with factor A for 12 wk. After the treatment of animals, the gastric mucosal inflammation was significantly different from that in controls, and the number of pyloric glands at antrum and parietal cells at body were obviously reduced (P<0.01). Indomethacin induced gastritis but without atrophy, and short-term vitamin deficiency failed to induce chronic gastritis and gastric atrophy, In addition,indomethacin and vitamin deficiency had no synergistic effect in inducing gastritis with the factor A. No atypical hyperplasia and intestinal metaplasia in the gastric antrum and body were observed in all rats studied.CONCLUSION: Combined intragastric administration of 600 mL/L alcohol, 20 mmol/L sodium deoxycholate and 0.5 g/L ammonia induces chronic gastritis and gastric atrophy in rats. Indomethacin induces chronic gastritis only.The long-term roles of these factors in gastric inflammation and carcinogenesis need to be further elucidated.

  15. Protective Effects and Mechanisms of Salvianolic Acid B Against H₂O₂-Induced Injury in Induced Pluripotent Stem Cell-Derived Neural Stem Cells.

    Science.gov (United States)

    Shu, Tao; Pang, Mao; Rong, Limin; Liu, Chang; Wang, Juan; Zhou, Wei; Wang, Xuan; Liu, Bin

    2015-06-01

    Induced pluripotent stem cells (iPSCs) have the potential to differentiate into neural lineages. Salvianolic acid B (Sal B) is a commonly used, traditional Chinese medicine for enhancing neuroprotective effects, and has antioxidant, anti-inflammatory, and antiapoptotic properties. Here, we explore the potential mechanism of Sal B in protecting iPSC-derived neural stem cells (NSCs) against H2O2-induced injury. iPSCs were induced into NSCs, iPSC-derived NSCs were treated with 50 μM Sal B for 24.5 h and 500 μM H2O2 for 24 h. The resulting effects were examined by flow cytometry analysis, quantitative reverse-transcription polymerase chain reaction, and western blotting. Upon H2O2 exposure, Sal B significantly promoted cell viability and stabilization of the mitochondrial membrane potential. Sal B also visibly decreased the cell apoptotic ratio. In addition, Sal B markedly reduced expression of matrix metalloproteinase (MMP)-2 and -9, and phosphospecific signal transducer and activator of transcription 3 (p-STAT3), and increased the level of tissue inhibitor of metalloproteinase (TIMP)-2 in iPSC-derived NSCs induced by H2O2. These results suggest that Sal B protects iPSC-derived NSCs against H2O2-induced oxidative stress. The mechanisms of this stress tolerance may be attributed to modulation of the MMP/TIMP system and inhibition of the STAT3 signaling pathway.

  16. Dynamic and differential regulation of stem cell factor FoxD3 in the neural crest is Encrypted in the genome.

    Directory of Open Access Journals (Sweden)

    Marcos S Simões-Costa

    Full Text Available The critical stem cell transcription factor FoxD3 is expressed by the premigratory and migrating neural crest, an embryonic stem cell population that forms diverse derivatives. Despite its important role in development and stem cell biology, little is known about what mediates FoxD3 activity in these cells. We have uncovered two FoxD3 enhancers, NC1 and NC2, that drive reporter expression in spatially and temporally distinct manners. Whereas NC1 activity recapitulates initial FoxD3 expression in the cranial neural crest, NC2 activity recapitulates initial FoxD3 expression at vagal/trunk levels while appearing only later in migrating cranial crest. Detailed mutational analysis, in vivo chromatin immunoprecipitation, and morpholino knock-downs reveal that transcription factors Pax7 and Msx1/2 cooperate with the neural crest specifier gene, Ets1, to bind to the cranial NC1 regulatory element. However, at vagal/trunk levels, they function together with the neural plate border gene, Zic1, which directly binds to the NC2 enhancer. These results reveal dynamic and differential regulation of FoxD3 in distinct neural crest subpopulations, suggesting that heterogeneity is encrypted at the regulatory level. Isolation of neural crest enhancers not only allows establishment of direct regulatory connections underlying neural crest formation, but also provides valuable tools for tissue specific manipulation and investigation of neural crest cell identity in amniotes.

  17. ADRA2B genotype differentially modulates stress-induced neural activity in the amygdala and hippocampus during emotional memory retrieval.

    Science.gov (United States)

    Li, Shijia; Weerda, Riklef; Milde, Christopher; Wolf, Oliver T; Thiel, Christiane M

    2015-02-01

    Noradrenaline interacts with stress hormones in the amygdala and hippocampus to enhance emotional memory consolidation, but the noradrenergic-glucocorticoid interaction at retrieval, where stress impairs memory, is less understood. We used a genetic neuroimaging approach to investigate whether a genetic variation of the noradrenergic system impacts stress-induced neural activity in amygdala and hippocampus during recognition of emotional memory. This study is based on genotype-dependent reanalysis of data from our previous publication (Li et al. Brain Imaging Behav 2014). Twenty-two healthy male volunteers were genotyped for the ADRA2B gene encoding the α2B-adrenergic receptor. Ten deletion carriers and 12 noncarriers performed an emotional face recognition task, while their brain activity was measured with fMRI. During encoding, 50 fearful and 50 neutral faces were presented. One hour later, they underwent either an acute stress (Trier Social Stress Test) or a control procedure which was followed immediately by the retrieval session, where participants had to discriminate between 100 old and 50 new faces. A genotype-dependent modulation of neural activity at retrieval was found in the bilateral amygdala and right hippocampus. Deletion carriers showed decreased neural activity in the amygdala when recognizing emotional faces in control condition and increased amygdala activity under stress. Noncarriers showed no differences in emotional modulated amygdala activation under stress or control. Instead, stress-induced increases during recognition of emotional faces were present in the right hippocampus. The genotype-dependent effects of acute stress on neural activity in amygdala and hippocampus provide evidence for noradrenergic-glucocorticoid interaction in emotional memory retrieval.

  18. Pyrolysed 3D-Carbon Scaffolds Induce Spontaneous Differentiation of Human Neural Stem Cells and Facilitate Real-Time Dopamine Detection

    DEFF Research Database (Denmark)

    Amato, Letizia; Heiskanen, Arto; Caviglia, Claudia

    2014-01-01

    Structurally patterned pyrolysed three-dimensional carbon scaffolds (p3Dcarbon) are fabricated and applied for differentiation of human neural stem cells (hNSCs) developed for cell replacement therapy and sensing of released dopamine. In the absence of differentiation factors (DF) the pyrolysed...... carbon material induces spontaneous hNSC differentiation into mature dopamine-producing neurons and the 3D-topography promotes neurite elongation. In the presence and absence of DF, ≈73–82% of the hNSCs obtain dopaminergic properties on pyrolysed carbon, a to-date unseen efficiency in both two......-dimensional (2D) and 3D environment. Due to conductive properties and 3D environment, the p3D-carbon serves as a neurotransmitter trap, enabling electrochemical detection of a signifi cantly larger dopamine fraction released by the hNSC derived neurons than on conventional 2D electrodes. This is the first study...

  19. High glucose-induced oxidative stress represses sirtuin deacetylase expression and increases histone acetylation leading to neural tube defects.

    Science.gov (United States)

    Yu, Jingwen; Wu, Yanqing; Yang, Peixin

    2016-05-01

    Aberrant epigenetic modifications are implicated in maternal diabetes-induced neural tube defects (NTDs). Because cellular stress plays a causal role in diabetic embryopathy, we investigated the possible role of the stress-resistant sirtuin (SIRT) family histone deacetylases. Among the seven sirtuins (SIRT1-7), pre-gestational maternal diabetes in vivo or high glucose in vitro significantly reduced the expression of SIRT 2 and SIRT6 in the embryo or neural stem cells, respectively. The down-regulation of SIRT2 and SIRT6 was reversed by superoxide dismutase 1 (SOD1) over-expression in the in vivo mouse model of diabetic embryopathy and the SOD mimetic, tempol and cell permeable SOD, PEGSOD in neural stem cell cultures. 2,3-dimethoxy-1,4-naphthoquinone (DMNQ), a superoxide generating agent, mimicked high glucose-suppressed SIRT2 and SIRT6 expression. The acetylation of histone 3 at lysine residues 56 (H3K56), H3K14, H3K9, and H3K27, putative substrates of SIRT2 and SIRT6, was increased by maternal diabetes in vivo or high glucose in vitro, and these increases were blocked by SOD1 over-expression or tempol treatment. SIRT2 or SIRT6 over-expression abrogated high glucose-suppressed SIRT2 or SIRT6 expression, and prevented the increase in acetylation of their histone substrates. The potent sirtuin activator (SRT1720) blocked high glucose-increased histone acetylation and NTD formation, whereas the combination of a pharmacological SIRT2 inhibitor and a pan SIRT inhibitor mimicked the effect of high glucose on increased histone acetylation and NTD induction. Thus, diabetes in vivo or high glucose in vitro suppresses SIRT2 and SIRT6 expression through oxidative stress, and sirtuin down-regulation-induced histone acetylation may be involved in diabetes-induced NTDs. The mechanism underlying pre-gestational diabetes-induced neural tube defects (NTDs) is still elusive. Our study unravels a new epigenetic mechanism in which maternal diabetes-induced oxidative stress represses

  20. PROBABILISTIC PROPERTIES OF THE INITIAL VALUES OF WEIGHTING FACTORS IN SYNCHRONIZED ARTIFICIAL NEURAL

    Directory of Open Access Journals (Sweden)

    V. F. Golikov

    2013-01-01

    Full Text Available One of the most efficient ways for identical binary se quences generation is using methods of neural cryptography. The initial weight vestors values influence on speed of synchronization is analized. Equal probability of initial weight vestors motion directions is great advantage. On this base authors suppose new line of research conserned with improvement of network architecture and correction algorithm.

  1. Metamizole Sodium Induces Neural Tube Defects in a Chick Embryo Model.

    Science.gov (United States)

    Guvenc, Yahya; Billur, Deniz; Aydin, Sevim; Ozeren, Ersin; Demirci, Adnan; Alagoz, Fatih; Dalgic, Ali; Belen, Deniz

    The aim of this study was to investigate the effects of metamizole sodium on neural tube development in the early stage chick embryo model that complies with the first month of embryonic development in mammals. A total of 40 fertilized chicken eggs were divided into 4 equal groups. The eggs were incubated in the incubator at a temperature of 37.8±2°C with 60±5% humidity. Group A was the control, Group B was administered physiological saline, Group C was administered 30 mg/kg metamizole sodium (based on the therapeutic index range of it used in humans) and Group D was administered 90 mg/kg metamizole sodium. All embryos were removed from the egg at the 48th hour and morphologically and histologically examined. Normal development was seen and the neural tube was closed in 17 embryos in Groups A and B. A neural tube defect was seen in 2 embryos in group A and in 1 embryo in group B. A neural tube closure defect was seen in all embryos in group C and 9 embryos in group D. There was 1 dead embryo in Group D. Metamizole sodium was seen to produce a neural tube defect in the chicken embyro model.

  2. Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation through activating the NR2B subunits of NMDA receptors

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Wen-Zhu [Anesthesia and Operation Center, Hainan Branch of Chinese PLA General Hospital, Hainan 572013 (China); Anesthesia and Operation Center, Chinese PLA General Hospital, Beijing 100853 (China); Miao, Yu-Liang [Department of Anesthesiology, PLA No. 306 Hospital, Beijing 100101 (China); Guo, Wen-Zhi [Department of Anesthesiology, Beijing Military General Hospital of Chinese People’s Liberation Army, Beijing 100700 (China); Wu, Wei, E-mail: wwzwgk@163.com [Department of Head and Neck Surgery of Otolaryngology, PLA No. 306 Hospital, Beijing 100101 (China); Li, Bao-Wei [Department of Head and Neck Surgery of Otolaryngology, PLA No. 306 Hospital, Beijing 100101 (China); An, Li-Na [Department of Anesthesiology, Armed Police General Hospital, Beijing 100039 (China); Fang, Wei-Wu [Department of Anesthesiology, PLA No. 306 Hospital, Beijing 100101 (China); Mi, Wei-Dong, E-mail: elite2005gg@163.com [Anesthesia and Operation Center, Chinese PLA General Hospital, Beijing 100853 (China)

    2014-04-25

    Highlights: • Leptin promotes the proliferation of neural stem cells isolated from embryonic mouse hippocampus. • Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation. • The effects of leptin are partially mediated by upregulating NR2B subunits. - Abstract: Corticosterone inhibits the proliferation of hippocampal neural stem cells (NSCs). The removal of corticosterone-induced inhibition of NSCs proliferation has been reported to contribute to neural regeneration. Leptin has been shown to regulate brain development, improve angiogenesis, and promote neural regeneration; however, its effects on corticosterone-induced inhibition of NSCs proliferation remain unclear. Here we reported that leptin significantly promoted the proliferation of hippocampal NSCs in a concentration-dependent pattern. Also, leptin efficiently reversed the inhibition of NSCs proliferation induced by corticosterone. Interestingly, pre-treatment with non-specific NMDA antagonist MK-801, specific NR2B antagonist Ro 25-6981, or small interfering RNA (siRNA) targeting NR2B, significantly blocked the effect of leptin on corticosterone-induced inhibition of NSCs proliferation. Furthermore, corticosterone significantly reduced the protein expression of NR2B, whereas pre-treatment with leptin greatly reversed the attenuation of NR2B expression caused by corticosterone in cultured hippocampal NSCs. Our findings demonstrate that leptin reverses the corticosterone-induced inhibition of NSCs proliferation. This process is, at least partially mediated by increased expression of NR2B subunits of NMDA receptors.

  3. Imipramine induces brain-derived neurotrophic factor mRNA expression in cultured astrocytes.

    Science.gov (United States)

    Takano, Katsura; Yamasaki, Hiroshi; Kawabe, Kenji; Moriyama, Mitsuaki; Nakamura, Yoichi

    2012-01-01

    Depression is one of the most prevalent and livelihood-threatening forms of mental illnesses and the neural circuitry underlying depression remains incompletely understood. Recent studies suggest that the neuronal plasticity involved with brain-derived neurotrophic factor (BDNF) plays an important role in the recovery from depression. Some antidepressants are reported to induce BDNF expression in vivo; however, the mechanisms have been considered solely in neurons and not fully elucidated. In the present study, we evaluated the effects of imipramine, a classic tricyclic antidepressant drug, on BDNF expression in cultured rat brain astrocytes. Imipramine dose-dependently increased BDNF mRNA expression in astrocytes. The imipramine-induced BDNF increase was suppressed with inhibitors for protein kinase A (PKA) or MEK/ERK. Moreover, imipramine exposure activated transcription factor cAMP response element binding protein (CREB) in a dose-dependent manner. These results suggested that imipramine induced BDNF expression through CREB activation via PKA and/or ERK pathways. Imipramine treatment in depression might exert antidepressant action through BDNF production from astrocytes, and glial BDNF expression might be a target of developing novel antidepressants.

  4. An update on risk factors for drug-induced arrhythmias.

    Science.gov (United States)

    Vlachos, Konstantinos; Georgopoulos, Stamatis; Efremidis, Michael; Sideris, Antonios; Letsas, Konstantinos P

    2016-01-01

    A variety of drugs, either anti-arrhythmics or non-antiarrhythmics, have been associated with drug-induced arrhythmias. Drug-induced arrhythmias are usually observed in the presence of long QT interval or Brugada electrocardiographic pattern. Clinical risk factors, such as female gender, structural heart disease, metabolic and electrolyte abnormalities, bradycardia and conduction disease, increased drug bioavailability, and silent channelopathies act as ''effect amplifiers'' which can make an otherwise relatively safe drug dangerous with regard to risk for polymorphic ventricular tachycardia in the setting of QT interval prolongation. A drug-induced type 1 electrocardiographic pattern of Brugada syndrome is considered highly proarrhythmic. Specific electrocardiographic markers including the corrected QT interval, QRS duration, Tpeak-Tend/QT ratio, and others may predict the risk of arrhythmias in both situations. The present review highlights on the current clinical and electrocardiographic risk factors for prediction of drug-induced arrhythmias.

  5. Neural crest cells: from developmental biology to clinical interventions.

    Science.gov (United States)

    Noisa, Parinya; Raivio, Taneli

    2014-09-01

    Neural crest cells are multipotent cells, which are specified in embryonic ectoderm in the border of neural plate and epiderm during early development by interconnection of extrinsic stimuli and intrinsic factors. Neural crest cells are capable of differentiating into various somatic cell types, including melanocytes, craniofacial cartilage and bone, smooth muscle, and peripheral nervous cells, which supports their promise for cell therapy. In this work, we provide a comprehensive review of wide aspects of neural crest cells from their developmental biology to applicability in medical research. We provide a simplified model of neural crest cell development and highlight the key external stimuli and intrinsic regulators that determine the neural crest cell fate. Defects of neural crest cell development leading to several human disorders are also mentioned, with the emphasis of using human induced pluripotent stem cells to model neurocristopathic syndromes. © 2014 Wiley Periodicals, Inc.

  6. Role of bone marrow mesenchymal stem cells in repair of neural cell injury induced by okadaic acid

    Directory of Open Access Journals (Sweden)

    Jia-jing LIU

    2017-06-01

    Full Text Available Objective To study whether the human bone marrow mesenchymal stem cells (HBMSCs can repair damaged neural cells induced by okadaic acid (OA. Methods Neuroblastoma cell line SH-SY5Y cells were used to incubate with 20nmol/L okadaic acid for 24h, establishing Alzheimer's Disease cell model; Three groups were set up: normal group, okadaic acid -damaged (OA-damaged group, hBMSCs -treatment group. The cells were injured for 24h with 20nmol/L OA in OA-damaged group, and treated with conditioned medium obtaining hBMSCs for 24h after 24h OA injury in the treatment group. Then CCK-8 was used for detecting cell vitality, immune fluorescence dyed microtubules and microfilaments for determining the dendritic cell length and fluorescence intensity, in addition, Western blotting for analyzing the protein level of phosphorylated tau and total tau proteins. Results Okadaic acid damaged SH-SY5Y cells, contributed to shrinkage, collapse, cavitation of the SH-SY5Y cell body, dendritic shortening and fracture, and irregular arrangement of microtubule microfilaments; while BMSCs conditioned medium made SH- SY5Y cell body become round and longer, dendrites restored, and microtubules and microfilaments arranged regularly, fluorescence intensity enhanced. Meanwhile,it also down-regulated the level of OA-induced tau phosphorylation. Conclusion hBMSCs have repair effects on the neural cell damage induced by okadaic acid. DOI: 10.11855/j.issn.0577-7402.2017.05.04

  7. Self-Organizing 3D Human Neural Tissue Derived from Induced Pluripotent Stem Cells Recapitulate Alzheimer's Disease Phenotypes.

    Science.gov (United States)

    Raja, Waseem K; Mungenast, Alison E; Lin, Yuan-Ta; Ko, Tak; Abdurrob, Fatema; Seo, Jinsoo; Tsai, Li-Huei

    2016-01-01

    The dismal success rate of clinical trials for Alzheimer's disease (AD) motivates us to develop model systems of AD pathology that have higher predictive validity. The advent of induced pluripotent stem cells (iPSCs) allows us to model pathology and study disease mechanisms directly in human neural cells from healthy individual as well as AD patients. However, two-dimensional culture systems do not recapitulate the complexity of neural tissue, and phenotypes such as extracellular protein aggregation are difficult to observe. We report brain organoids that use pluripotent stem cells derived from AD patients and recapitulate AD-like pathologies such as amyloid aggregation, hyperphosphorylated tau protein, and endosome abnormalities. These pathologies are observed in an age-dependent manner in organoids derived from multiple familial AD (fAD) patients harboring amyloid precursor protein (APP) duplication or presenilin1 (PSEN1) mutation, compared to controls. The incidence of AD pathology was consistent amongst several fAD lines, which carried different mutations. Although these are complex assemblies of neural tissue, they are also highly amenable to experimental manipulation. We find that treatment of patient-derived organoids with β- and γ-secretase inhibitors significantly reduces amyloid and tau pathology. Moreover, these results show the potential of this model system to greatly increase the translatability of pre-clinical drug discovery in AD.

  8. Dual small-molecule targeting of SMAD signaling stimulates human induced pluripotent stem cells toward neural lineages.

    Directory of Open Access Journals (Sweden)

    Methichit Wattanapanitch

    Full Text Available Incurable neurological disorders such as Parkinson's disease (PD, Huntington's disease (HD, and Alzheimer's disease (AD are very common and can be life-threatening because of their progressive disease symptoms with limited treatment options. To provide an alternative renewable cell source for cell-based transplantation and as study models for neurological diseases, we generated induced pluripotent stem cells (iPSCs from human dermal fibroblasts (HDFs and then differentiated them into neural progenitor cells (NPCs and mature neurons by dual SMAD signaling inhibitors. Reprogramming efficiency was improved by supplementing the histone deacethylase inhibitor, valproic acid (VPA, and inhibitor of p160-Rho associated coiled-coil kinase (ROCK, Y-27632, after retroviral transduction. We obtained a number of iPS colonies that shared similar characteristics with human embryonic stem cells in terms of their morphology, cell surface antigens, pluripotency-associated gene and protein expressions as well as their in vitro and in vivo differentiation potentials. After treatment with Noggin and SB431542, inhibitors of the SMAD signaling pathway, HDF-iPSCs demonstrated rapid and efficient differentiation into neural lineages. Six days after neural induction, neuroepithelial cells (NEPCs were observed in the adherent monolayer culture, which had the ability to differentiate further into NPCs and neurons, as characterized by their morphology and the expression of neuron-specific transcripts and proteins. We propose that our study may be applied to generate neurological disease patient-specific iPSCs allowing better understanding of disease pathogenesis and drug sensitivity assays.

  9. Classification of wrought aluminum alloys by Artificial Neural Networks evaluation of Laser Induced Breakdown Spectroscopy spectra from aluminum scrap samples

    Science.gov (United States)

    Campanella, B.; Grifoni, E.; Legnaioli, S.; Lorenzetti, G.; Pagnotta, S.; Sorrentino, F.; Palleschi, V.

    2017-08-01

    Every year throughout the world > 50 million vehicles reach the end of their life, producing millions of tons of automotive waste. The current strategies for the separation of the non-ferrous waste fraction, contain mainly aluminum, magnesium, zinc and copper alloys, involve high investment and operational costs, and pose environmental concerns. The European project SHREDDERSORT, in which our research group was actively involved, aimed to overcome this issue by developing a new dry sorting technology for the shredding of non-ferrous automotive wastes. This work represents one step of the complex SHREDDERSORT project, dedicated to the development of a strategy based on Laser Induced Breakdown Spectroscopy (LIBS) for the sorting of light alloys. LIBS was here applied in laboratory for the analysis of stationary aluminum shredder samples. To process the LIBS spectra a methodological approach based on artificial neural networks was used. Although separation could in principle be based on simple emission line ratios, the neural networks approach enables more reproducible results, which can accommodate the unavoidable signal variations due to the low intrinsic reproducibility of the LIBS systems. The neural network separated samples into different clusters and estimates their elemental concentrations.

  10. Neural circuits of disgust induced by sexual stimuli in homosexual and heterosexual men: An fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Minming [Department of Radiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou (China); Hu Shaohua [Department of Mental Health, First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qing Chun Road, Hangzhou, Zhejiang Province 310003 (China); Xu Lijuan [National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing (China); Wang Qidong [Department of Radiology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou (China); Xu Xiaojun [Department of Radiology, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou (China); Wei Erqing [College of Pharmacology, Zhejiang University (China); Yan Leqin [MD Anderson Cancer Center, Virginia Harris Cockrell Cancer Research Center, University of Texas, Austin (United States); Hu Jianbo; Wei Ning; Zhou Weihua; Huang Manli [Department of Mental Health, First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qing Chun Road, Hangzhou, Zhejiang Province 310003 (China); Xu Yi, E-mail: xuyi61@yahoo.com.cn [Department of Mental Health, First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qing Chun Road, Hangzhou, Zhejiang Province 310003 (China)

    2011-11-15

    Few studies demonstrated neural circuits related to disgust were influenced by internal sexual orientation in male. Here we used fMRI to study the neural responses to disgust in homosexual and heterosexual men to investigate that issue. Thirty-two healthy male volunteers (sixteen homosexual and sixteen heterosexual) were scanned while viewing alternating blocks of three types of erotic film: heterosexual couples (F-M), male homosexual couples (M-M), and female homosexual couples (F-F) engaged in sexual activity. All the participants rated their level of disgust and sexual arousal as well. The F-F and M-M stimuli induced disgust in homosexual and heterosexual men, respectively. The common activations related to disgusting stimuli included: bilateral frontal gyrus and occipital gyrus, right middle temporal gyrus, left superior temporal gyrus, right cerebellum, and right thalamus. Homosexual men had greater neural responses in the left medial frontal gyrus than did heterosexual men to the sexual disgusting stimuli; in contrast, heterosexual men showed significantly greater activation than homosexual men in the left cuneus. ROI analysis showed that negative correlation were found between the magnitude of MRI signals in the left medial frontal gyrus and scores of disgust in homosexual subjects (p < 0.05). This study indicated that there were regions in common as well as regions specific for each type of erotic stimuli during disgust of homosexual and heterosexual men.

  11. Neural circuits of disgust induced by sexual stimuli in homosexual and heterosexual men: an fMRI study.

    Science.gov (United States)

    Zhang, Minming; Hu, Shaohua; Xu, Lijuan; Wang, Qidong; Xu, Xiaojun; Wei, Erqing; Yan, Leqin; Hu, Jianbo; Wei, Ning; Zhou, Weihua; Huang, Manli; Xu, Yi

    2011-11-01

    Few studies demonstrated neural circuits related to disgust were influenced by internal sexual orientation in male. Here we used fMRI to study the neural responses to disgust in homosexual and heterosexual men to investigate that issue. Thirty-two healthy male volunteers (sixteen homosexual and sixteen heterosexual) were scanned while viewing alternating blocks of three types of erotic film: heterosexual couples (F-M), male homosexual couples (M-M), and female homosexual couples (F-F) engaged in sexual activity. All the participants rated their level of disgust and sexual arousal as well. The F-F and M-M stimuli induced disgust in homosexual and heterosexual men, respectively. The common activations related to disgusting stimuli included: bilateral frontal gyrus and occipital gyrus, right middle temporal gyrus, left superior temporal gyrus, right cerebellum, and right thalamus. Homosexual men had greater neural responses in the left medial frontal gyrus than did heterosexual men to the sexual disgusting stimuli; in contrast, heterosexual men showed significantly greater activation than homosexual men in the left cuneus. ROI analysis showed that negative correlation were found between the magnitude of MRI signals in the left medial frontal gyrus and scores of disgust in homosexual subjects (ptype of erotic stimuli during disgust of homosexual and heterosexual men.

  12. Changes in metabolic proteins in ex vivo rat retina during glutamate-induced neural progenitor cell induction.

    Science.gov (United States)

    Tokuda, Kazuhiro; Kuramitsu, Yasuhiro; Baron, Byron; Kitagawa, Takao; Tokuda, Nobuko; Kobayashi, Masaaki; Kimura, Kazuhiro; Sonoda, Koh-Hei; Nakamura, Kazuyuki

    2016-08-01

    Understanding how energy metabolism and related proteins influence neural progenitor cells in adult tissues is critical for developing new strategies in clinical tissue regeneration therapy. We have recently reported that a subtoxic concentration of glutamate-induced neural progenitor cells in the mature ex vivo rat retina. We herein explore changes in the metabolic pathways during the process. We firstly observed an increase in lactate and lactate dehydrogenase concentration in the glutamate-treated retina. We then investigated the levels of glycolytic enzymes and confirmed significant upregulation of pyruvate kinase M type (PKM), especially PKM2, enolase, phosphoglycerate mutase 1 (PGAM1), and inosine-5'-monophosphate dehydrogenase (IMPDH1) in the glutamate-treated retina compared to the untreated retina. An analysis of the subcellular localization of PKM2 revealed nuclear translocation in the treated retina, which has been reported to regulate cell cycle proliferation and glycolytic enzymes. Our findings indicate that the mature rat retina undergoes an increase in aerobic glycolysis. PKM2, both in the cytoplasm and in the nucleus, may thus play an important role during neural progenitor cell induction, as it does in other proliferating cells.

  13. Hypoxia-Inducible Factor as an Angiogenic Master Switch

    Science.gov (United States)

    Hashimoto, Takuya; Shibasaki, Futoshi

    2015-01-01

    Hypoxia-inducible factors (HIFs) regulate the transcription of genes that mediate the response to hypoxia. HIFs are constantly expressed and degraded under normoxia, but stabilized under hypoxia. HIFs have been widely studied in physiological and pathological conditions and have been shown to contribute to the pathogenesis of various vascular diseases. In clinical settings, the HIF pathway has been studied for its role in inhibiting carcinogenesis. HIFs might also play a protective role in the pathology of ischemic diseases. Clinical trials of therapeutic angiogenesis after the administration of a single growth factor have yielded unsatisfactory or controversial results, possibly because the coordinated activity of different HIF-induced factors is necessary to induce mature vessel formation. Thus, manipulation of HIF activity to simultaneously induce a spectrum of angiogenic factors offers a superior strategy for therapeutic angiogenesis. Because HIF-2α plays an essential role in vascular remodeling, manipulation of HIF-2α is a promising approach to the treatment of ischemic diseases caused by arterial obstruction, where insufficient development of collateral vessels impedes effective therapy. Eukaryotic initiation factor 3 subunit e (eIF3e)/INT6 interacts specifically with HIF-2α and induces the proteasome inhibitor-sensitive degradation of HIF-2α, independent of hypoxia and von Hippel-Lindau protein. Treatment with eIF3e/INT6 siRNA stabilizes HIF-2α activity even under normoxic conditions and induces the expression of several angiogenic factors, at levels sufficient to produce functional arteries and veins in vivo. We have demonstrated that administration of eIF3e/INT6 siRNA to ischemic limbs or cold-injured brains reduces ischemic damage in animal models. This review summarizes the current understanding of the relationship between HIFs and vascular diseases. We also discuss novel oxygen-independent regulatory proteins that bind HIF-α and the implications

  14. Activation of mTor Signaling by Gene Transduction to Induce Axon Regeneration in the Central Nervous System Following Neural Injury

    Science.gov (United States)

    2015-03-01

    Central Nervous System Following Neural Injury PRINCIPAL INVESTIGATOR: Robert E. Burke, MD CONTRACTING ORGANIZATION: COLUMBIA UNIVERSITY MEDICAL...Transduction to Induce Axon Regeneration in the Central Nervous System Following Neural Injury 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-12-1-0051 5c...INTRODUCTION A longstanding concept in neuroscience has been that the mature mammalian central nervous system (CNS), unlike the peripheral nervous system (PNS

  15. Use of an artificial neural network to predict risk factors of nosocomial infection in lung cancer patients.

    Science.gov (United States)

    Chen, Jie; Pan, Qin-Shi; Hong, Wan-Dong; Pan, Jingye; Zhang, Wen-Hui; Xu, Gang; Wang, Yu-Min

    2014-01-01

    Statistical methods to analyze and predict the related risk factors of nosocomial infection in lung cancer patients are various, but the results are inconsistent. A total of 609 patients with lung cancer were enrolled to allow factor comparison using Student's t-test or the Mann-Whitney test or the Chi-square test. Variables that were significantly related to the presence of nosocomial infection were selected as candidates for input into the final ANN model. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the performance of the artificial neural network (ANN) model and logistic regression (LR) model. The prevalence of nosocomial infection from lung cancer in this entire study population was 20.1% (165/609), nosocomial infections occurring in sputum specimens (85.5%), followed by blood (6.73%), urine (6.0%) and pleural effusions (1.82%). It was shown that long term hospitalization (≥ 22 days, P= 0.000), poor clinical stage (IIIb and IV stage, P=0.002), older age (≥ 61 year old, P=0.023), and use the hormones were linked to nosocomial infection and the ANN model consisted of these four factors .The artificial neural network model with variables consisting of age, clinical stage, time of hospitalization, and use of hormones should be useful for predicting nosocomial infection in lung cancer cases.

  16. Ets Factors Regulate Neural Stem Cell Depletion and Gliogenesis in Ras Pathway Glioma.

    Science.gov (United States)

    Breunig, Joshua J; Levy, Rachelle; Antonuk, C Danielle; Molina, Jessica; Dutra-Clarke, Marina; Park, Hannah; Akhtar, Aslam Abbasi; Kim, Gi Bum; Hu, Xin; Bannykh, Serguei I; Verhaak, Roel G W; Danielpour, Moise

    2015-07-14

    As the list of putative driver mutations in glioma grows, we are just beginning to elucidate the effects of dysregulated developmental signaling pathways on the transformation of neural cells. We have employed a postnatal, mosaic, autochthonous glioma model that captures the first hours and days of gliomagenesis in more resolution than conventional genetically engineered mouse models of cancer. We provide evidence that disruption of the Nf1-Ras pathway in the ventricular zone at multiple signaling nodes uniformly results in rapid neural stem cell depletion, progenitor hyperproliferation, and gliogenic lineage restriction. Abolishing Ets subfamily activity, which is upregulated downstream of Ras, rescues these phenotypes and blocks glioma initiation. Thus, the Nf1-Ras-Ets axis might be one of the select molecular pathways that are perturbed for initiation and maintenance in glioma.

  17. Axon guidance factor SLIT2 inhibits neural invasion and metastasis in pancreatic cancer.

    Science.gov (United States)

    Göhrig, Andreas; Detjen, Katharina M; Hilfenhaus, Georg; Körner, Jan L; Welzel, Martina; Arsenic, Ruza; Schmuck, Rosa; Bahra, Marcus; Wu, Jane Y; Wiedenmann, Bertram; Fischer, Christian

    2014-03-01

    Pancreatic ductal adenocarcinoma (PDAC) metastasizes by neural, vascular, and local invasion routes, which limit patient survival. In nerves and vessels, SLIT2 and its ROBO receptors constitute repellent guidance cues that also direct epithelial branching. Thus, the SLIT2-ROBO system may represent a key pinch point to regulate PDAC spread. In this study, we examined the hypothesis that escaping from repellent SLIT2-ROBO signaling is essential to enable PDAC cells to appropriate their local stromal infrastructure for dissemination. Through immunohistochemical analysis, we detected SLIT2 receptors ROBO1 and ROBO4 on epithelia, nerves, and vessels in healthy pancreas and PDAC specimens, respectively. SLIT2 mRNA expression was reduced in PDAC compared with nontransformed pancreatic tissues and cell lines, suggesting a reduction in SLIT2-ROBO pathway activity in PDAC. In support of this interpretation, restoring the SLIT2 expression in SLIT2-deficient PDAC cells inhibited their bidirectional chemoattraction with neural cells, and more specifically, impaired unidirectional PDAC cell navigation along outgrowing neurites in models of neural invasion. Restoring autocrine/paracrine SLIT2 signaling was also sufficient to inhibit the directed motility of PDAC cells, but not their random movement. Conversely, RNA interference-mediated silencing of ROBO1 stimulated the motility of SLIT2-competent PDAC cells. Furthermore, culture supernatants from SLIT2-competent PDAC cells impaired migration of endothelial cells (human umbilical vein endothelial cells), whereas an N-terminal SLIT2 cleavage fragment stimulated such migration. In vivo investigations of pancreatic tumors with restored SLIT2 expression demonstrated reduced invasion, metastasis, and vascularization, with opposing effects produced by ROBO1 silencing in tumor cells or sequestration of endogenous SLIT2. Analysis of clinical specimens of PDAC showed that those with low SLIT2 mRNA expression exhibited a higher incidence

  18. Folic Acid Protected Neural Cells Against Aluminum-Maltolate-Induced Apoptosis by Preventing miR-19 Downregulation.

    Science.gov (United States)

    Zhu, Mingming; Li, Bingfei; Ma, Xiao; Huang, Cong; Wu, Rui; Zhu, Weiwei; Li, Xiaoting; Liang, Zhaofeng; Deng, Feifei; Zhu, Jianyun; Xie, Wei; Yang, Xue; Jiang, Ye; Wang, Shijia; Wu, Jieshu; Geng, Shanshan; Xie, Chunfeng; Zhong, Caiyun; Liu, Haiyan

    2016-08-01

    Aluminum (Al)-induced apoptosis is considered as the major cause of its neurotoxicity. Folic acid possesses neuroprotective function by preventing neural cell apoptosis. microRNAs (miRNAs) are important regulators of gene expression participating in cellular processes. As a key component of the miR-17-92 cluster, miR-19 is implicated in regulating apoptotic process, while its role in the neuroprotective effect of folic acid has not been investigated. The present study aimed to investigate the potential involvement and function of miR-19 in the protective action of folic acid against Al-induced neural cell apoptosis. Human SH-SY5Y cells were treated with Al-maltolate (Al-malt) in the presence or absence of folic acid. Results showed that Al-malt-induced apoptosis of SH-SY5Y cells was effectively prevented by folic acid. Al-malt suppressed the expression of miR-19a/19b, along with alterations of miR-19 related apoptotic proteins including PTEN, p-AKT, p53, Bax, Bcl-2, caspase 9 and caspase 3; and these effects were ameliorated by folic acid. miR-19 inhibitor alone induced apoptosis of SH-SY5Y cells. Combination treatment of folic acid and miR-19 inhibitor diminished the neuroprotective effect of folic acid. These findings demonstrated that folic acid protected neuronal cells against Al-malt-induced apoptosis by preventing the downregulation of miR-19 and modulation of miR-19 related downstream PTEN/AKT/p53 pathway.

  19. Expression of chondrogenic potential of mouse trunk neural crest cells by FGF2 treatment.

    Science.gov (United States)

    Ido, Atsushi; Ito, Kazuo

    2006-02-01

    There is a significant difference between the developmental patterns of cranial and trunk neural crest cells in the amniote. Thus, whereas cranial neural crest cells generate bone and cartilage, trunk neural crest cells do not contribute to skeletal derivatives. We examined whether mouse trunk neural crest cells can undergo chondrogenesis to analyze how the difference between the developmental patterns of cranial and trunk neural crest cells arises. Our present data demonstrate that mouse trunk neural crest cells have chondrogenic potential and that fibroblast growth factor (FGF) 2 is an inducing factor for their chondrogenesis in vitro. FGF2 altered the expression patterns of Hox9 genes and Id2, a cranial neural crest cell marker. These results suggest that environmental cues may play essential roles in generating the difference between developmental patterns of cranial and trunk neural crest cells. Copyright 2005 Wiley-Liss, Inc.

  20. Human insulin-like growth factor 1-transfected umbilical cord blood neural stem cell transplantation improves hypoxic-ischemic brain injury

    Institute of Scientific and Technical Information of China (English)

    Dengna Zhu; Yanjie Jia; Jun Wang; Boai Zhang; Guohui Niu; Yazhen Fan

    2011-01-01

    Human insulin-like growth factor 1-transfected umbilical cord blood neural stem cells were transplanted into a hypoxic-ischemic neonatal rat model via the tail vein.BrdU-positive cells at day 7post-transplantation,as well as nestin-and neuron specific enolase-positive cells at day 14 wereincreased compared with those of the single neural stem cell transplantation group.In addition,theproportion of neuronal differentiation was enhanced.The genetically modified cell-transplanted ratsexhibited enhanced performance in correctly crossing a Y-maze and climbing an angled slope compared with those of the single neural stem cell transplantation group.These results showed that human insulin-like growth factor 1-transfected neural stem cell transplantation promotes therecovery of the learning,memory and motor functions in hypoxic-ischemic rats.

  1. Neurotoxicity of human neural cells induced by space radiation: in vitro risk assessment and countermeasure

    Science.gov (United States)

    Guida, P.; Vazquez, M.; Kim, A.

    As the duration of space missions increases the potential for neurological damage to astronauts resulting from exposure to radiation also increases To explore the cytotoxic effects of low and high LET radiation on cells of the central nervous system we utilized a model in vitro system consisting of a human neuronal progenitor cell line NT2 and its terminally differentiated derivative hNT neurons We found that exposure to numerous forms of ionizing radiation induced cell detachment necrosis and apoptosis in time dose and LET dependent manners From the slopes of the dose-response curves we calculated RBE values for each form of heavy ion radiation A sequential field of 1 GeV n protons and iron ions induced apoptosis to a greater extent than either ion alone and the time between hits was also an important determining factor In addition cycling neuronal progenitor cells underwent a dramatic G2 phase specific cell cycle delay within 6 hours following exposure to either low or high LET radiation The molecular effects of HZE radiation were also investigated with an emphasis on the cell stress response protein p53 Heavy ion radiation induced expression of p53 in a time and dose dependent manner in both neuronal progenitor and mature neuronal cells Furthermore several post-translational modifications to the p53 protein were detected 2 hours after exposure to gamma rays Experiments incorporating pifithrin- alpha a small molecule inhibitor of p53 suggest that induction of both apoptosis and the cell cycle delay in human NT2 cells is

  2. Induced pluripotent stem cells and their use in cardiac and neural regenerative medicine.

    Science.gov (United States)

    Skalova, Stepanka; Svadlakova, Tereza; Shaikh Qureshi, Wasay Mohiuddin; Dev, Kapil; Mokry, Jaroslav

    2015-02-13

    Stem cells are unique pools of cells that are crucial for embryonic development and maintenance of adult tissue homeostasis. The landmark Nobel Prize winning research by Yamanaka and colleagues to induce pluripotency in somatic cells has reshaped the field of stem cell research. The complications related to the usage of pluripotent embryonic stem cells (ESCs) in human medicine, particularly ESC isolation and histoincompatibility were bypassed with induced pluripotent stem cell (iPSC) technology. The human iPSCs can be used for studying embryogenesis, disease modeling, drug testing and regenerative medicine. iPSCs can be diverted to different cell lineages using small molecules and growth factors. In this review we have focused on iPSC differentiation towards cardiac and neuronal lineages. Moreover, we deal with the use of iPSCs in regenerative medicine and modeling diseases like myocardial infarction, Timothy syndrome, dilated cardiomyopathy, Parkinson's, Alzheimer's and Huntington's disease. Despite the promising potential of iPSCs, genome contamination and low efficacy of cell reprogramming remain significant challenges.

  3. Integrated analysis of genetic, behavioral, and biochemical data implicates neural stem cell-induced changes in immunity, neurotransmission and mitochondrial function in Dementia with Lewy Body mice.

    Science.gov (United States)

    Lakatos, Anita; Goldberg, Natalie R S; Blurton-Jones, Mathew

    2017-03-10

    We previously demonstrated that transplantation of murine neural stem cells (NSCs) can improve motor and cognitive function in a transgenic model of Dementia with Lewy Bodies (DLB). These benefits occurred without changes in human α-synuclein pathology and were mediated in part by stem cell-induced elevation of brain-derived neurotrophic factor (BDNF). However, instrastriatal NSC transplantation likely alters the brain microenvironment via multiple mechanisms that may synergize to promote cognitive and motor recovery. The underlying neurobiology that mediates such restoration no doubt involves numerous genes acting in concert to modulate signaling within and between host brain cells and transplanted NSCs. In order to identify functionally connected gene networks and additional mechanisms that may contribute to stem cell-induced benefits, we performed weighted gene co-expression network analysis (WGCNA) on striatal tissue isolated from NSC- and vehicle-injected wild-type and DLB mice. Combining continuous behavioral and biochemical data with genome wide expression via network analysis proved to be a powerful approach; revealing significant alterations in immune response, neurotransmission, and mitochondria function. Taken together, these data shed further light on the gene network and biological processes that underlie the therapeutic effects of NSC transplantation on α-synuclein induced cognitive and motor impairments, thereby highlighting additional therapeutic targets for synucleinopathies.

  4. Stem Cells from Human Exfoliated Deciduous Tooth Exhibit Stromal-Derived Inducing Activity and Lead to Generation of Neural Crest Cells from Human Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Khadijeh Karbalaie

    2015-04-01

    Full Text Available Objective: The neural crest is a transient structure of early vertebrate embryos that generates neural crest cells (NCCs. These cells can migrate throughout the body and produce a diverse array of mature tissue types. Due to the ethical and technical problems surrounding the isolation of these early human embryo cells, researchers have focused on in vitro studies to produce NCCs and increase their knowledge of neural crest development. Materials and Methods: In this experimental study, we cultured human embryonic stem cells (hESCs on stromal stem cells from human exfoliated deciduous teeth (SHED for a two-week period. We used different approaches to characterize these differentiated cells as neural precursor cells (NPCs and NCCs. Results: In the first co-culture week, hESCs appeared as crater-like structures with marginal rosettes. NPCs derived from these structures expressed the early neural crest marker p75 in addition to numerous other genes associated with neural crest induction such as SNAIL, SLUG, PTX3 and SOX9. Flow cytometry analysis showed 70% of the cells were AP2/P75 positive. Moreover, the cells were able to self-renew, sustain multipotent differentiation potential, and readily form neurospheres in suspension culture. Conclusion: SHED, as an adult stem cell with a neural crest origin, has stromal-derived inducing activity (SDIA and can be used as an NCC inducer from hESCs. These cells provide an invaluable resource to study neural crest differentiation in both normal and disordered human neural crest development.

  5. Growth factor involvement in tension-induced skeletal muscle growth

    Science.gov (United States)

    Vandenburgh, Herman H.

    1993-01-01

    Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

  6. Expression of hypoxia-inducible factor 1 alpha and oligodendrocyte lineage gene-1 in cultured brain slices after oxygen-glucose deprivation

    Institute of Scientific and Technical Information of China (English)

    Hong Cui; Weijuan Han; Lijun Yang; Yanzhong Chang

    2013-01-01

    Oligodendrocyte lineage gene-1 expressed in oligodendrocytes may trigger the repair of neuronal myelin impairment, and play a crucial role in myelin repair. Hypoxia-inducible factor 1α, a transcription factor, is of great significance in premature infants with hypoxic-ischemic brain damage. There is little evidence of direct regulatory effects of hypoxia-inducible factor 1α on oligodendrocyte lineage gene-1. In this study, brain slices of Sprague-Dawley rats were cultured and subjected to oxygen-glucose deprivation. Then, slices were transfected with hypoxia-inducible factor 1α or oligodendrocyte lineage gene-1. The expression levels of hypoxia-inducible factor 1α and oligodendrocyte lineage gene-1 were significantly up-regulated in rat brains prior to transfection, as detected by immunohistochemical staining. Eight hours after transfection of slices with hypoxia-inducible factor 1α, oligodendrocyte lineage gene-1 expression was upregulated, and reached a peak 24 hours after transfection. Oligodendrocyte lineage gene-1 transfection induced no significant differences in hypoxia-inducible factor 1α levels in rat brain tissues with oxygen-glucose deprivation. These experimental findings indicate that hypoxia-inducible factor 1α can regulate oligodendrocyte lineage gene-1 expression in hypoxic brain tissue, thus repairing the neural impairment.

  7. Platelet-rich fibrin-induced bone marrow mesenchymal stem cell differentiation into osteoblast-like cells and neural cells

    Institute of Scientific and Technical Information of China (English)

    Qi Li; Yajun Geng; Lei Lu; Tingting Yang; Mingrui Zhang; Yanmin Zhou

    2011-01-01

    Bone marrow mesenchymal stem cells were allowed to develop for 14 days in a platelet-rich fibrin environment. Results demonstrated that platelet-rich fibrin significantly promoted bone marrow mesenchymal stem cell proliferation. In addition, there was a dose-dependent increase in Runt-related transcription factor-2 and bone morphogenetic protein-2 mRNA expression, as well as neuron-specific enolase and glial acidic protein. Results showed that platelet-rich fibrin promoted bone marrow mesenchymal stem cell proliferation and differentiation of osteoblastlike cells and neural cells in a dose-dependent manner.

  8. Leukemia Inhibitory Factor Induces Neurotransmitter Switching in Transgenic Mice

    Science.gov (United States)

    Bamber, Bruce A.; Masters, Brian A.; Hoyle, Gary W.; Brinster, Ralph L.; Palmiter, Richard D.

    1994-08-01

    Leukemia inhibitory factor (LIF) is a cytokine growth factor that induces rat sympathetic neurons to switch their neurotransmitter phenotype from noradrenergic to cholinergic in vitro. To test whether LIF can influence neuronal differentiation in vivo, we generated transgenic mice that expressed LIF in pancreatic islets under the control of the insulin promoter and evaluated the neurotransmitter phenotype of the pancreatic sympathetic innervation. We also used the insulin promoter to coexpress nerve growth factor in the islets, which greatly increased the density of sympathetic innervation and facilitated analysis of the effects of LIF. Our data demonstrate that tyrosine hydroxylase and catecholamines declined and choline acetyltransferase increased in response to LIF. We conclude that LIF can induce neurotransmitter switching of sympathetic neurons in vivo.

  9. Chromatin remodelling factor Mll1 is essential for neurogenesis from postnatal neural stem cells

    Science.gov (United States)

    Lim, Daniel A.; Huang, Yin-Cheng; Swigut, Tomek; Mirick, Anika L.; Garcia-Verdugo, Jose Manuel; Wysocka, Joanna; Ernst, Patricia; Alvarez-Buylla, Arturo

    2013-01-01

    Epigenetic mechanisms that maintain neurogenesis throughout adult life remain poorly understood1. Trithorax group (trxG) and Polycomb group (PcG) gene products are part of an evolutionarily conserved chromatin remodelling system that activate or silence gene expression, respectively2. Although PcG member Bmi1 has been shown to be required for postnatal neural stem cell self-renewal3,4, the role of trxG genes remains unknown. Here we show that the trxG member Mll1 (mixed-lineage leukaemia 1) is required for neurogenesis in the mouse postnatal brain. Mll1-deficient subventricular zone neural stem cells survive, proliferate and efficiently differentiate into glial lineages; however, neuronal differentiation is severely impaired. In Mll1-deficient cells, early proneural Mash1 (also known as Ascl1) and gliogenic Olig2 expression are preserved, but Dlx2, a key downstream regulator of subventricular zone neurogenesis, is not expressed. Over-expression of Dlx2 can rescue neurogenesis in Mll1-deficient cells. Chromatin immunoprecipitation demonstrates that Dlx2 is a direct target of MLL in subventricular zone cells. In differentiating wild-type subventricular zone cells, Mash1, Olig2 and Dlx2 loci have high levels of histone 3 trimethylated at lysine 4 (H3K4me3), consistent with their transcription. In contrast, in Mll1-deficient subventricular zone cells, chromatin at Dlx2 is bivalently marked by both H3K4me3 and histone 3 trimethylated at lysine 27 (H3K27me3), and the Dlx2 gene fails to properly activate. These data support a model in which Mll1 is required to resolve key silenced bivalent loci in postnatal neural precursors to the actively transcribed state for the induction of neurogenesis, but not for gliogenesis. PMID:19212323

  10. An Evaluation of Sensory Neural Hearing Loss in Thalassaemic Patients Treated with Desferrioxamine and Its Risk Factors

    Directory of Open Access Journals (Sweden)

    M Sonbolestan

    2005-07-01

    Full Text Available Back ground: In major thalassaemia patients who need blood transfusion, iron overload is a major therapeutic disadvantage that leads to heart failure which is the major cause of death in such patients. Desferrioxamine (DFO is the most efficient factor for iron chelation, but it carries adverse effects such sensory-neural hearing loss. Methods: The study began in March 2002 and continued untill March 2003, on 160 cases of thalassaemia to determine the incidence of sensory – neural hearing loss and its risk factors in patients who received Desferrioxamine (DFO. All cases underwent audiometric tests. Retrospectively, other needed information were either obtained through interview or extracted from the medical files. Results were analyzed with ANOVA, t-test and Chi-square tests. Results: Seventy-six patients of the total 156 patients showed impairment in PTA (48.7% with 24 of them suffering significant involvement (15.4%. These abnormalities generally affected high frequencies including, 4000 and 8000 Hz. Male gender, increased serum billirubin level and fasting blood sugar were statistically correlated with hearing loss (p.v = 0.038, p.v = 0.38, p.v = 0.002 respectively. There was no significant correlation between hearing loss and other factors. Mean DFO administration in patients, was 29.69 mg/kg/day and mean therapeutic index of DFO was 0.01 mg/kg/day/mg/lit. Both of them were below the critical level (<40mg/kg/day and <0.025mg/kg/day/mg/lit respectively, however hearing loss had developed. Conclusion: Controlling DFO dosage per se does not seem to be enough for decreasing ototoxicity rate. Periodic audiometric tests are highly recommended to detect hearing loss as soon as possible. There are some other factors such as male gender, increased billirubin and FBS, which contribute to DFO ototoxicity. Looking for these risk factors and controlling them, would help identifying susceptible patients and preventing this complication. Key words

  11. Factors that modify risks of radiation-induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1988-11-01

    The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors).

  12. Factors that modify risks of radiation-induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1988-11-01

    The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors).

  13. Small-World Connections to Induce Firing Activity and Phase Synchronization in Neural Networks

    Institute of Scientific and Technical Information of China (English)

    QIN Ying-Hua; LUO Xiao-Shu

    2009-01-01

    We investigate how the firing activity and the subsequent phase synchronization of neural networks with small-world topological connections depend on the probability p of adding-links. Network elements are described by two-dimensional map neurons (2DMNs) in a quiescent original state. Neurons burst for a given coupling strength when the topological randomness p increases, which is absent in a regular-lattice neural network. The bursting activity becomes frequent and synchronization of neurons emerges as topological randomness further increases.The maximal firing frequency and phase synchronization appear at a particular value of p. However, if the randomness p further increases, the firing frequency decreases and synchronization is apparently destroyed.

  14. Distinct steps of neural induction revealed by Asterix, Obelix and TrkC, genes induced by different signals from the organizer.

    Directory of Open Access Journals (Sweden)

    Sonia Pinho

    Full Text Available The amniote organizer (Hensen's node can induce a complete nervous system when grafted into a peripheral region of a host embryo. Although BMP inhibition has been implicated in neural induction, non-neural cells cannot respond to BMP antagonists unless previously exposed to a node graft for at least 5 hours before BMP inhibitors. To define signals and responses during the first 5 hours of node signals, a differential screen was conducted. Here we describe three early response genes: two of them, Asterix and Obelix, encode previously undescribed proteins of unknown function but Obelix appears to be a nuclear RNA-binding protein. The third is TrkC, a neurotrophin receptor. All three genes are induced by a node graft within 4-5 hours but they differ in the extent to which they are inducible by FGF: FGF is both necessary and sufficient to induce Asterix, sufficient but not necessary to induce Obelix and neither sufficient nor necessary for induction of TrkC. These genes are also not induced by retinoic acid, Noggin, Chordin, Dkk1, Cerberus, HGF/SF, Somatostatin or ionomycin-mediated Calcium entry. Comparison of the expression and regulation of these genes with other early neural markers reveals three distinct "epochs", or temporal waves, of gene expression accompanying neural induction by a grafted organizer, which are mirrored by specific stages of normal neural plate development. The results are consistent with neural induction being a cascade of responses elicited by different signals, culminating in the formation of a patterned nervous system.

  15. Basic fibroblast growth factor increases the number of endogenous neural stem cells and inhibits the expression of amino methyl isoxazole propionic acid receptors in amyotrophic lateral sclerosis mice

    Institute of Scientific and Technical Information of China (English)

    Weihui Huang; Dawei Zang; Yi Lu; Ping Jiang

    2012-01-01

    This study aimed to investigate the number of amino methyl isoxazole propionic acid (AMPA) re-ceptors and production of endogenous neural stem cells in the SOD1G93AG1H transgenic mouse model of amyotrophic lateral sclerosis, at postnatal day 60 following administration of basic fibroblast growth factor (FGF-2). A radioligand binding assay and immunohistochemistry were used to estimate the number of AMPA receptors and endogenous neural stem cells respectively. Results showed that the number of AMPA receptors and endogenous neural stem cells in the brain stem and sensorimotor cortex were significantly increased, while motor function was significantly decreased at postnatal days 90 and 120. After administration of FGF-2 into mice, numbers of endogenous neural stem cells increased, while expression of AMPA receptors decreased, whilst motor functions were recovered. At postnatal day 120, the number of AMPA receptors was negatively correlated with the number of endogenous neural stem cells in model mice and FGF-2-treated mice. Our experimental findings indicate that FGF-2 can inhibit AMPA receptors and increase the number of endogenous neural stem cells, thus repairing neural injury in amyotrophic lateral sclerosis mice.

  16. Identifying and Prioritizing the Determinative factors of Customers Repeat Purchasing in Etka Chain Stores by Using Neural Networks Algorithm

    Directory of Open Access Journals (Sweden)

    Behrooz Jahandideh

    2013-01-01

    Full Text Available Nowadays, chain stores are experiencing a severe competitive environment. In such anenvironment, a growing number of customers are equipped by high volumes of informationand are more risk-taking. As they tend to switch their store based on the higher value thatthey might receive elsewhere, as customers switching behavior has become so commonplaceand has become a challenge for retailers. Thus, factors that influence the willingness ofcustomers to repurchase will play a critical role in the performance and success of chainstores. This paper aimed to identify and prioritize the determinative factors that causecustomers repeat patronage in Etka chain stores. Factors were extracted based on a thoroughliterature review and then these factors were modified using pre-test and interview methods.In this study, questionnaires were used for data collection. Respectively, to identify andprioritize determinative factors, correlation analysis and artificial neural networks were used.Results showed that in order of importance, quality, price loyalty program, number of servicecounters, store staff, shelf labels, product selection, parking facilities, home delivery, storebrand, and store atmosphere are factors that determine customers’ repeat patronage of Etkachain stores. Meanwhile, young, educated and wealthy customers showed lower store repeatpatronage. Finally, the paper concludes with suggestions for increasing consumer repeatpatronageof Etka chain-stores and directions for future research

  17. Identifying and prioritizing factors that influence reapeted patronage of Etka chain-stores customers: a neural network approach

    Directory of Open Access Journals (Sweden)

    Behrouz Jahandideh

    2013-03-01

    Full Text Available Nowadays, chain stores are experiencing a severe competitive environment. In such an environment, a growing number of customers are equipped by high volumes of information and are more risk-taking. As they tend to switch their store based on the higher value that they might receive elsewhere, as customers switching behavior has become so commonplace and has become a challenge for retailers. Thus, factors that influence the willingness of customers to repurchase will play a critical role in the performance and success of chain stores. This paper aimed to identify and prioritize the determinative factors that cause customers repeat patronage in Etka chain stores. Factors were extracted based on a thorough literature review and then these factors were modified using pre-test and interview methods. In this study, questionnaires were used for data collection. Respectively, to identify and prioritize determinative factors, correlation analysis and artificial neural networks were used. Results showed that in order of importance, quality, price loyalty program, number of service counters, store staff, shelf labels, product selection, parking facilities, home delivery, store brand, and store atmosphere are factors that determine customers’ repeat patronage of Etka chain stores. Meanwhile, young, educated and wealthy customers showed lower store repeat patronage. Finally, the paper concludes with suggestions for increasing consumer repeat-patronage of Etka chain-stores and directions for future research.

  18. Taurine Induces Proliferation of Neural Stem Cells and Synapse Development in the Developing Mouse Brain

    Science.gov (United States)

    Shivaraj, Mattu Chetana; Marcy, Guillaume; Low, Guoliang; Ryu, Jae Ryun; Zhao, Xianfeng; Rosales, Francisco J.; Goh, Eyleen L. K.

    2012-01-01

    Taurine is a sulfur-containing amino acid present in high concentrations in mammalian tissues. It has been implicated in several processes involving brain development and neurotransmission. However, the role of taurine in hippocampal neurogenesis during brain development is still unknown. Here we show that taurine regulates neural progenitor cell (NPC) proliferation in the dentate gyrus of the developing brain as well as in cultured early postnatal (P5) hippocampal progenitor cells and hippocampal slices derived from P5 mice brains. Taurine increased cell proliferation without having a significant effect on neural differentiation both in cultured P5 NPCs as well as cultured hippocampal slices and in vivo. Expression level analysis of synaptic proteins revealed that taurine increases the expression of Synapsin 1 and PSD 95. We also found that taurine stimulates the phosphorylation of ERK1/2 indicating a possible role of the ERK pathway in mediating the changes that we observed, especially in proliferation. Taken together, our results demonstrate a role for taurine in neural stem/progenitor cell proliferation in developing brain and suggest the involvement of the ERK1/2 pathways in mediating these actions. Our study also shows that taurine influences the levels of proteins associated with synapse development. This is the first evidence showing the effect of taurine on early postnatal neuronal development using a combination of in vitro, ex-vivo and in vivo systems. PMID:22916184

  19. Neural plasticity and stress induced changes in defense in the rat.

    Science.gov (United States)

    Adamec, R E; Blundell, J; Collins, A

    2001-12-01

    We investigated the effects of predator stress on behavior and amygdala afferent and efferent neural transmission in rats. Pathways studied were: ventral angular bundle input to the basolateral amygdala; central and basolateral amygdala output to the periaqueductal gray (PAG). Predator stress was 'anxiogenic' in elevated plus maze, light/dark box and acoustic startle tests one week after stress. Lasting changes were also observed in neural transmission. Predator stress appeared to potentiate right and depotentiate left hemisphere afferent amygdala transmission. In contrast, predator stress potentiated amygdala efferent transmission to right and left PAG, depending on the amygdala nucleus stimulated. Paired pulse and intensity series analysis suggests that transmission changes may be postsynaptic or presynaptic, depending on the pathway. Path analysis relating brain and behavioral changes suggests that potentiation and depotentiation in both hemispheres participate jointly in effecting some, but not all, of the behavioral changes produced by predator stress. Potentiation in left hemisphere amygdala afferents and efferents predicts anxiolytic-like effects, while potentiation in the right hemisphere amygdala afferents predicts anxiogenic-like effects. Path analysis also supports the view that changes in different neural systems mediate changes in different behaviors. These findings have their parallel in studies in the cat, but there are species differences.

  20. C5a receptor signaling prevents folate deficiency-induced neural tube defects in mice.

    Science.gov (United States)

    Denny, Kerina J; Coulthard, Liam G; Jeanes, Angela; Lisgo, Steven; Simmons, David G; Callaway, Leonie K; Wlodarczyk, Bogdan; Finnell, Richard H; Woodruff, Trent M; Taylor, Stephen M

    2013-04-01

    The complement system is involved in a range of diverse developmental processes, including cell survival, growth, differentiation, and regeneration. However, little is known about the role of complement in embryogenesis. In this study, we demonstrate a novel role for the canonical complement 5a receptor (C5aR) in the development of the mammalian neural tube under conditions of maternal dietary folic acid deficiency. Specifically, we found C5aR and C5 to be expressed throughout the period of neurulation in wild-type mice and localized the expression to the cephalic regions of the developing neural tube. C5aR was also found to be expressed in the neuroepithelium of early human embryos. Ablation of the C5ar1 gene or the administration of a specific C5aR peptide antagonist to folic acid-deficient pregnant mice resulted in a high prevalence of severe anterior neural tube defect-associated congenital malformations. These findings provide a new and compelling insight into the role of the complement system during mammalian embryonic development.

  1. Human neural stem cells genetically modified to overexpress brain-derived neurotrophic factor promote functional recovery and neuroprotection in a mouse stroke model.

    Science.gov (United States)

    Lee, Hong J; Lim, In J; Lee, Min C; Kim, Seung U

    2010-11-15

    Intracerebral hemorrhage (ICH) is a lethal stroke type; mortality approaches 50%, and current medical therapy against ICH shows only limited effectiveness, so an alternative approach is required, such as stem cell-based cell therapy. Previously we have shown that intravenously transplanted human neural stem cells (NSCs) selectively migrate to the brain and promote functional recovery in rat ICH model, and others have shown that intracerebral infusion of brain-derived neurotrophic factor (BDNF) results in improved structural and functional outcome from cerebral ischemia. We postulated that human NSCs overexpressing BDNF transplanted into cerebral cortex overlying ICH lesion could provide improved survival of grafted NSCs and increased angiogenesis and behavioral recovery in mouse ICH model. ICH was induced in adult mice by injection of bacterial collagenase into striatum. The HB1.F3.BDNF (F3.BDNF) human NSC line produces sixfold higher amounts of BDNFF over the parental F3 cell line in vitro, induces behavioral improvement, and produces a threefold increase in cell survival at 2 weeks and 8 weeks posttransplantation. Brain transplantation of human NSCs overexpressing BDNF provided differentiation and survival of grafted human NSCs and renewed angiogenesis of host brain and functional recovery of ICH animals. These results indicate that the F3.BDNF human NSCs should be of great value as a cellular source for experimental studies involving cellular therapy for human neurological disorders, including ICH.

  2. Risk factors, organ weight deviation and associated anomalies in neural tube defects: A prospective fetal and perinatal autopsy series

    Directory of Open Access Journals (Sweden)

    Asaranti Kar

    2015-01-01

    Full Text Available Introduction: Neural tube defects (NTD are a group of serious birth defects occurring due to defective closure of neural tube during embryonic development. It comprises of anencephaly, encephalocele and spina bifida. We conducted this prospective fetal autopsy series to study the rate and distribution of NTD, analyze the reproductive factors and risk factors, note any associated anomalies and evaluate the organ weights and their deviation from normal. Materials and Methods: This was a prospective study done over a period of 6 years from August, 2007 to July, 2013. All cases of NTDs delivered as abortion, still born and live born were included. The reproductive and risk factors like age, parity, multiple births, previous miscarriage, obesity, diabetes mellitus, socioeconomic status and use of folic acid during pregnancy were collected.Autopsy was performed according to Virchow′s technique. Detail external and internal examination were carried out to detect any associated anomalies. Gross and microscopic examination of organs were done. Results: Out of 210 cases of fetal and perinatal autopsy done, 72 (34.28% had NTD constituting 49 cases of anencephaly, 16 spina bifida and 7 cases of encephalocele. The mothers in these cases predominantly were within 25-29 years (P = 0.02 and primy (P = 0.01. Female sex was more commonly affected than males (M:F = 25:47, P = 0.0005 There was no history of folate use in majority of cases. Organ weight deviations were >2 standard deviation low in most of the cases. Most common associated anomalies were adrenal hypoplasia and thymic hyperplasia. Conclusion: The authors have made an attempt to study NTD cases in respect to maternal reproductive and risk factors and their association with NTD along with the organ weight deviation and associated anomalies. This so far in our knowledge is an innovative study which was not found in literature even after extensive search.

  3. Placental Growth Factor Administration Abolishes Placental Ischemia-Induced Hypertension.

    Science.gov (United States)

    Spradley, Frank T; Tan, Adelene Y; Joo, Woo S; Daniels, Garrett; Kussie, Paul; Karumanchi, S Ananth; Granger, Joey P

    2016-04-01

    Preeclampsia is a pregnancy-specific disorder of new-onset hypertension. Unfortunately, the most effective treatment is early delivery of the fetus and placenta. Placental ischemia appears central to the pathogenesis of preeclampsia because placental ischemia/hypoxia induced in animals by reduced uterine perfusion pressure (RUPP) or in humans stimulates release of hypertensive placental factors into the maternal circulation. The anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), which antagonizes and reduces bioavailable vascular endothelial growth factor and placental growth factor (PlGF), is elevated in RUPP rats and preeclampsia. Although PlGF and vascular endothelial growth factor are both natural ligands for sFlt-1, vascular endothelial growth factor also has high affinity to VEGFR2 (Flk-1) causing side effects like edema. PlGF is specific for sFlt-1. We tested the hypothesis that PlGF treatment reduces placental ischemia-induced hypertension by antagonizing sFlt-1 without adverse consequences to the mother or fetus. On gestational day 14, rats were randomized to 4 groups: normal pregnant or RUPP±infusion of recombinant human PlGF (180 μg/kg per day; AG31, a purified, recombinant human form of PlGF) for 5 days via intraperitoneal osmotic minipumps. On day 19, mean arterial blood pressure and plasma sFlt-1 were higher and glomerular filtration rate lower in RUPP than normal pregnant rats. Infusion of recombinant human PlGF abolished these changes seen with RUPP along with reducing oxidative stress. These data indicate that the increased sFlt-1 and reduced PlGF resulting from placental ischemia contribute to maternal hypertension. Our novel finding that recombinant human PlGF abolishes placental ischemia-induced hypertension, without major adverse consequences, suggests a strong therapeutic potential for this growth factor in preeclampsia.

  4. Elastase induces lung epithelial cell autophagy through placental growth factor

    Science.gov (United States)

    Hou, Hsin-Han; Cheng, Shih-Lung; Chung, Kuei-Pin; Kuo, Mark Yen-Ping; Yeh, Cheng-Chang; Chang, Bei-En; Lu, Hsuan-Hsuan; Wang, Hao-Chien; Yu, Chong-Jen

    2014-01-01

    Chronic obstructive pulmonary disease (COPD) is a devastating disease, which is associated with increasing mortality and morbidity. Therefore, there is a need to clearly define the COPD pathogenic mechanism and to explore effective therapies. Previous studies indicated that cigarette smoke (CS) induces autophagy and apoptosis in lung epithelial (LE) cells. Excessive ELANE/HNE (elastase, neutrophil elastase), a factor involved in protease-antiprotease imbalance and the pathogenesis of COPD, causes LE cell apoptosis and upregulates the expression of several stimulus-responsive genes. However, whether or not elastase induces autophagy in LE cell remains unknown. The level of PGF (placental growth factor) is higher in COPD patients than non-COPD controls. We hypothesize that elastase induces PGF expression and causes autophagy in LE cells. In this study, we demonstrated that porcine pancreatic elastase (PPE) induced PGF expression and secretion in LE cells in vitro and in vivo. The activation of MAPK8/JNK1 (mitogen-activated protein kinase 8) and MAPK14/p38alpha MAPK signaling pathways was involved in the PGF mediated regulation of the TSC (tuberous sclerosis complex) pathway and autophagy in LE cells. Notably, PGF-induced MAPK8 and MAPK14 signaling pathways mediated the inactivation of MTOR (mechanistic target of rapamycin), the upregulation of MAP1LC3B/LC3B (microtubule-associated protein 1 light chain 3 β) and the increase of autophagosome formation in mice. Furthermore, the PPE-induced autophagy promotes further apoptosis in vitro and in vivo. In summary, elastase-induced autophagy promotes LE cell apoptosis and pulmonary emphysema through the upregulation of PGF. PGF and its downstream MAPK8 and MAPK14 signaling pathways are potential therapeutic targets for the treatment of emphysema and COPD. PMID:24988221

  5. The brain-specific neural zinc finger transcription factor 2b (NZF-2b/7ZFMyt1 suppresses cocaine self-administration in rats

    Directory of Open Access Journals (Sweden)

    Vijay Chandrasekar

    2010-04-01

    Full Text Available Brain-specific neural-zinc-finger transcription factor-2b (NZF2b/7ZFMyt1 is induced in the mesolimbic dopaminergic region after chronic cocaine exposure and lentiviral-mediated expression of NZF2b/7ZFMyt1 in the nucleus accumbens results in decreased locomotor activity (Chandrasekar and Dreyer, 2009. In this study the role of NZF2b/7ZFMyt1 in active cocaine seeking and of its interaction with histone deacetylase on the altered behavior has been observed. Localized expression of NZF2b/7ZFMyt1 in the nucleus accumbens resulted in attenuated cocaine self-administration, whereas silencing this transcription factor with lentiviruses expressing siRNAs increased the animal′s motivation to self-infuse cocaine. Low doses of sodium butyrate, a potent inhibitor of histone deacetylase, were sufficient to reverse the NZF2b/7ZFMyt1-mediated decrease in cocaine self-administration. NZF2b/7ZFMyt1 expression resulted in strong induction of transcription factors REST1 and NAC1 and of the dopamine D2 receptor, with concomitant inhibition of BDNF and its receptor TrkB. We show that NZF2b/7ZFMyt1 colocalizes with histone deacetylase-2 (HDAC2, probably overcoming the suppression of transcriptional activity caused by Lingo1. These findings show that molecular adaptations mediated by NZF2b/7ZFMyt1 expression possibly lead to decreased responsiveness to the reinforcing properties of cocaine and play a prominent role in affecting the behavioral changes induced by the drug.

  6. Study on correlations of modal frequencies and environmental factors for a suspension bridge based on improved neural networks

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    By using of long-term monitoring data of Runyang Suspension Bridge,the improved back-propagation neural networks (BPNNs) are formulated for modeling the correlations between modal frequencies and environmental conditions including wind,temperature and vehicle load.Then,with the correlation models the environmental effects on modal frequencies are quantified and the abnormal changes of measured frequencies are detected by means of the hypothesis tests.Analysis results reveal that BPNN-based correlation models improved by both early stopping and Bayesian regularization techniques exhibit excellent generalization capability.And the developed correlation models can effectively reduce the environmental variability in modal frequencies.The t-test method provides a good capability to detect the damage-induced 0.16% and 0.12% abnormal changes of the 5th and 6th modal frequencies,respectively.Hence,the proposed method is suitable for real-time monitoring of suspension bridge conditions.

  7. Exposure to titanium dioxide and other metallic oxide nanoparticles induces cytotoxicity on human neural cells and fibroblasts

    Directory of Open Access Journals (Sweden)

    James C K Lai

    2008-12-01

    Full Text Available James C K Lai1, Maria B Lai1, Sirisha Jandhyam1, Vikas V Dukhande1, Alok Bhushan1, Christopher K Daniels1, Solomon W Leung21Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, and Biomedical Research Institute; 2Department of Civil and Environmental Engineering, College of Engineering and Biomedical Research Institute, Idaho State University, Pocatello, ID, USAAbstract: The use of titanium dioxide (TiO2 in various industrial applications (eg, production of paper, plastics, cosmetics, and paints has been expanding thereby increasing the occupational and other environmental exposure of these nanoparticles to humans and other species. However, the health effects of exposure to TiO2 nanoparticles have not been systematically assessed even though recent studies suggest that such exposure induces inflammatory responses in lung tissue and cells. Because the effects of such nanoparticles on human neural cells are unknown, we have determined the putative cytotoxic effects of these nanoparticles on human astrocytes-like astrocytoma U87 cells and compared their effects on normal human fibroblasts. We found that TiO2 micro- and nanoparticles induced cell death on both human cell types in a concentration-related manner. We further noted that zinc oxide (ZnO nanoparticles were the most effective, TiO2 nanoparticles the second most effective, and magnesium oxide (MgO nanoparticles the least effective in inducing cell death in U87 cells. The cell death mechanisms underlying the effects of TiO2 micro- and nanoparticles on U87 cells include apoptosis, necrosis, and possibly apoptosis-like and necrosis-like cell death types. Thus, our findings may have toxicological and other pathophysiological implications on exposure of humans and other mammalian species to metallic oxide nanoparticles.Keywords: cytotoxicity of titanium dioxide micro- and nanoparticles, cytotoxicity of zinc oxide and magnesium oxide nanoparticles, human neural cells

  8. Modulation of the major histocompatibility complex by neural stem cell-derived neurotrophic factors used for regenerative therapy in a rat model of stroke

    Directory of Open Access Journals (Sweden)

    Sun Chongran

    2010-08-01

    Full Text Available Abstract Background The relationship between functional improvements in ischemic rats given a neural stem cell (NSC transplant and the modulation of the class I major histocompatibility complex (MHC mediated by NSC-derived neurotrophins was investigated. Methods The levels of gene expression of nerve growth factor (NGF, brain-derived neurotropic factor (BDNF and neurotrophin-3 (NT-3 were assayed from cultures of cortical NSC from Sprague-Dawley rat E16 embryos. The levels of translated NGF in spent culture media from NSC cultures and the cerebral spinal fluid (CSF of rats with and without NGF injection or NSC transplant were also measured. Results We found a significant increase of NGF, BDNF and NT-3 transcripts and NGF proteins in both the NSC cultures and the CSF of the rats. The immunochemical staining for MHC in brain sections and the enzyme-linked immunosorbent assay of CSF were carried out in sham-operated rats and rats with surgically induced focal cerebral ischemia. These groups were further divided into animals that did and did not receive NGF administration or NSC transplant into the cisterna magna. Our results show an up-regulation of class I MHC in the ischemic rats with NGF and NSC administration. The extent of caspase-III immunoreactivity was comparable among three arms in the ischemic rats. Conclusion Readouts of somatosensory evoked potential and the trap channel test illustrated improvements in the neurological function of ischemic rats treated with NGF administration and NSC transplant.

  9. Interindividual differences in stress sensitivity: basal and stress-induced cortisol levels differentially predict neural vigilance processing under stress.

    Science.gov (United States)

    Henckens, Marloes J A G; Klumpers, Floris; Everaerd, Daphne; Kooijman, Sabine C; van Wingen, Guido A; Fernández, Guillén

    2016-04-01

    Stress exposure is known to precipitate psychological disorders. However, large differences exist in how individuals respond to stressful situations. A major marker for stress sensitivity is hypothalamus-pituitary-adrenal (HPA)-axis function. Here, we studied how interindividual variance in both basal cortisol levels and stress-induced cortisol responses predicts differences in neural vigilance processing during stress exposure. Implementing a randomized, counterbalanced, crossover design, 120 healthy male participants were exposed to a stress-induction and control procedure, followed by an emotional perception task (viewing fearful and happy faces) during fMRI scanning. Stress sensitivity was assessed using physiological (salivary cortisol levels) and psychological measures (trait questionnaires). High stress-induced cortisol responses were associated with increased stress sensitivity as assessed by psychological questionnaires, a stronger stress-induced increase in medial temporal activity and greater differential amygdala responses to fearful as opposed to happy faces under control conditions. In contrast, high basal cortisol levels were related to relative stress resilience as reflected by higher extraversion scores, a lower stress-induced increase in amygdala activity and enhanced differential processing of fearful compared with happy faces under stress. These findings seem to reflect a critical role for HPA-axis signaling in stress coping; higher basal levels indicate stress resilience, whereas higher cortisol responsivity to stress might facilitate recovery in those individuals prone to react sensitively to stress. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  10. Evidence for increased SOX3 dosage as a risk factor for X-linked hypopituitarism and neural tube defects.

    Science.gov (United States)

    Bauters, Marijke; Frints, Suzanna G; Van Esch, Hilde; Spruijt, Liesbeth; Baldewijns, Marcella M; de Die-Smulders, Christine E M; Fryns, Jean-Pierre; Marynen, Peter; Froyen, Guy

    2014-08-01

    Genomic duplications of varying lengths at Xq26-q27 involving SOX3 have been described in families with X-linked hypopituitarism. Using array-CGH we detected a 1.1 Mb microduplication at Xq27 in a large family with three males suffering from X-linked hypopituitarism. The duplication was mapped from 138.7 to 139.8 Mb, harboring only two annotated genes, SOX3 and ATP11C, and was shown to be a direct tandem copy number gain. Unexpectedly, the microduplication did not fully segregate with the disease in this family suggesting that SOX3 duplications have variable penetrance for X-linked hypopituitarism. In the same family, a female fetus presenting with a neural tube defect was also shown to carry the SOX3 copy number gain. Since we also demonstrated increased SOX3 mRNA levels in amnion cells derived from an unrelated t(X;22)(q27;q11) female fetus with spina bifida, we propose that increased levels of SOX3 could be a risk factor for neural tube defects.

  11. The niche factor syndecan-1 regulates the maintenance and proliferation of neural progenitor cells during mammalian cortical development.

    Directory of Open Access Journals (Sweden)

    Qingjie Wang

    Full Text Available Neural progenitor cells (NPCs divide and differentiate in a precisely regulated manner over time to achieve the remarkable expansion and assembly of the layered mammalian cerebral cortex. Both intrinsic signaling pathways and environmental factors control the behavior of NPCs during cortical development. Heparan sulphate proteoglycans (HSPG are critical environmental regulators that help modulate and integrate environmental cues and downstream intracellular signals. Syndecan-1 (Sdc1, a major transmembrane HSPG, is highly enriched in the early neural germinal zone, but its function in modulating NPC behavior and cortical development has not been explored. In this study we investigate the expression pattern and function of Sdc1 in the developing mouse cerebral cortex. We found that Sdc1 is highly expressed by cortical NPCs. Knockdown of Sdc1 in vivo by in utero electroporation reduces NPC proliferation and causes their premature differentiation, corroborated in isolated cells in vitro. We found that Sdc1 knockdown leads to reduced levels of β-catenin, indicating reduced canonical Wnt signaling. Consistent with this, GSK3β inhibition helps rescue the Sdc1 knockdown phenotype, partially restoring NPC number and proliferation. Moreover, exogenous Wnt protein promotes cortical NPC proliferation, but this is prevented by Sdc1 knockdown. Thus, Sdc1 in the germinal niche is a key HSPG regulating the maintenance and proliferation of NPCs during cortical neurogenesis, in part by modulating the ability of NPCs to respond to Wnt ligands.

  12. 戊四氮诱导发育鼠癫痫持续状态后海马区HIF-1α的表达及其与神经干细胞增殖的关系%Expression of hypoxia-inducible factor-1 alpha and correlation between HIF-1α level and proliferation of neural stem cells in the hippocampus of developing rats after pentylenetetrazolinduced status epilepticus

    Institute of Scientific and Technical Information of China (English)

    周保健; 袁宝强

    2012-01-01

    Objective To explore the expressions of hypoxia-inducible factor-1 alpha (HIF- lα)and nestin in the hippocampus of developing rats after pentylenetetrazol (PTZ)-induced starus epilepticus (SE),and the correlation between HIF-1α level and proliferation of neural stem cells (NSCs). Methods A total of 768 SD rats,including rats of postnatal 7 days (P7,n-192),rats of postnatal 14 days (P14,n=192),rats of postnatal 21 days (P21,n=192) and rats of postnatal 28 days (P28,n=192),were equally randomized into vehicle group (n=96) and control group (n-96),respectively; SE rat models of the vehicle group were induced by intraperitoneal injection of 1% PTZ (80 mg/kg); and rats of the control group were received injection of normal saline (NS); 6 and 12 h,and 1,2,3 and 7 d after the inducement,the mRNA and protein expressions of HIF-1α in the hippocampus of rats in these 8 groups were examined by RT-PCR and immunohistochemistry, respectively. Another 48 21-d- old SD rats were equally randomized into vehicle I group (n=24) and intervention group (n=24); and rats in the intervention group received injection of HIF-lα antisense oligodeoxynucleotides (ASODN) into the right hippocampus and NS into the left hippocampus; 6 h after the injection,these 48 rats were induced into SE models by intraperitoneal injection of 1% PTZ (80 mg/kg); 2 d after the inducement, the mRNA expression of HIF-1α in the hippocampus was examined by RT-PCR; and 7 and 14 d after theinducement, the protein expressions of HIF-1α and nestin in the hippocampus were examined by immunohistochemistry. Results The mRNA expression of HIF-1 α in the hippocampus of all the rats in the vehicle group after SE increased significantly with similar trend.Six h after SE,the HIF-1α mRNA expression significantly decreased with time prolongation (P<0.05). Major HIF-1α positive cells were located in different areas at different time after SE. In intervention experiment, the HIF-1α mRNA expression 2 d after SE and

  13. Engineering Design Handbook: Environmental Series. Part Three. Induced Environmental Factors

    Science.gov (United States)

    1976-01-20

    3-18 3-12. Instruments for Sample Collection 9-19 3-13. Major Deserts of the World 3-20 3-14. Corrosion of Open- hearth Steel...lightning, but otherwise is overshadowed by artificial sources. Each of these induced environmental factors is also influenced greatly by natural...identification: 1. Open- hearth furnaces 2. Incineration 3. Cement plants 4. Fuel oil combustion 5. Coal combustion plus diffraction effects apply

  14. Vectorology and Factor Delivery in Induced Pluripotent Stem Cell Reprogramming

    OpenAIRE

    Hu, Kejin

    2014-01-01

    Induced pluripotent stem cell (iPSC) reprogramming requires sustained expression of multiple reprogramming factors for a limited period of time (10–30 days). Conventional iPSC reprogramming was achieved using lentiviral or simple retroviral vectors. Retroviral reprogramming has flaws of insertional mutagenesis, uncontrolled silencing, residual expression and re-activation of transgenes, and immunogenicity. To overcome these issues, various technologies were explored, including adenoviral vect...

  15. Dissociable neural systems underwrite logical reasoning in the context of induced emotions with positive and negative valence.

    Science.gov (United States)

    Smith, Kathleen W; Vartanian, Oshin; Goel, Vinod

    2014-01-01

    How emotions influence syllogistic reasoning is not well understood. fMRI was employed to investigate the effects of induced positive or negative emotion on syllogistic reasoning. Specifically, on a trial-by-trial basis participants were exposed to a positive, negative, or neutral picture, immediately prior to engagement in a reasoning task. After viewing and rating the valence and intensity of each picture, participants indicated by keypress whether or not the conclusion of the syllogism followed logically from the premises. The content of all syllogisms was neutral, and the influence of belief-bias was controlled for in the study design. Emotion did not affect reasoning performance, although there was a trend in the expected direction based on accuracy rates for the positive (63%) and negative (64%) versus neutral (70%) condition. Nevertheless, exposure to positive and negative pictures led to dissociable patterns of neural activation during reasoning. Therefore, the neural basis of deductive reasoning differs as a function of the valence of the context.

  16. Dissociable neural systems underwrite logical reasoning in the context of induced emotions with positive and negative valence

    Directory of Open Access Journals (Sweden)

    Kathleen Walton Smith

    2014-09-01

    Full Text Available How emotions influence syllogistic reasoning is not well understood. fMRI was employed to investigate the effects of induced positive or negative emotion on syllogistic reasoning. Specifically, on a trial-by-trial basis participants were exposed to a positive, negative, or neutral picture, immediately prior to engagement in a reasoning task. After viewing and rating the valence and intensity of each picture, participants indicated by keypress whether or not the conclusion of the syllogism followed logically from the premises. The content of all syllogisms was neutral, and the influence of belief-bias was controlled for in the study design. Emotion did not affect reasoning performance, although there was a trend in the expected direction based on accuracy rates for the positive (63% and negative (64% versus neutral (70% condition. Nevertheless, exposure to positive and negative pictures led to dissociable patterns of neural activation during reasoning. Therefore, the neural basis of deductive reasoning differs as a function of the valence of the context.

  17. Involvement of NOS3 in RA-Induced neural differentiation of human NT2/D1 cells.

    Science.gov (United States)

    Jezierski, Anna; Deb-Rinker, Paromita; Sodja, Caroline; Walker, P Roy; Ly, Dao; Haukenfrers, Julie; Sandhu, Jagdeep K; Bani-Yaghoub, Mahmud; Sikorska, Marianna

    2012-12-01

    Nitric oxide (NO) plays a key role in neurogenesis as a regulator of cell proliferation and differentiation. NO is synthesized from the amino acid L-arginine by nitric oxide synthases (NOS1, NOS2, and NOS3), which are encoded by separate genes and display different tissue distributions. We used an in vitro model of RA-induced neural differentiation of NT2 cells to examine which of the three NO-synthesizing enzymes is involved in this process. The results revealed a transient induction of NOS3 (known as the constitutively expressed endothelial nitric oxide synthase; eNOS) during the time course of the RA treatment. The peak of gene expression and the nuclear presence of NOS3 protein coincided with cell cycle exit of NT2-derived neuronal precursors. The subsequent analysis of cytosine methylation and histone H3 acetylation of the human NOS3 5' regulatory sequences indicated that epigenetic modifications, especially upstream of the proximal promoter (-734 to -989, relative to exon 2 TSS at +1), were also taking place. NOS1 was expressed only in the differentiated neurons (NT2-N), whereas NOS2 was not expressed at all in this cellular model. Thus, a burst of NO production, possibly required to inhibit neural cell proliferation, was generated by the transient expression of NOS3. This pattern of gene expression, in turn, required epigenetic remodeling of its regulatory region. Copyright © 2012 Wiley Periodicals, Inc.

  18. Clinical Aspects of Hypoxia-inducible Factors in Colorectal Cancer

    DEFF Research Database (Denmark)

    Havelund, Birgitte Mayland; Spindler, Karen-Lise Garm; Sørensen, Flemming Brandt;

    to a standardized scheme. 2. The prognostic value of HIF-1α is investigated by SNP analysis and HIF-1α expression in tissue from 300 patients operated for colorectal cancer and the results is validated in a prospectively population of 200 patients. 3. The predictive value of HIF-1α will be investigated in patients......Clinical Aspects of Hypoxia-inducible Factors in Colorectal Cancer   Birgitte Mayland Havelund1,4 MD, Karen-Lise Garm Spindler1,4 MD, PhD, Flemming Brandt Sørensen2,4 MD, DMSc, Ivan Brandslund3 MD, DMSc, Anders Jakobsen1,4 MD, DMSc. 1Department of Oncology, 2Pathology and 3Biochemistry, Vejle...... Hospital, Vejle, Denmark 4Institute of Regional Health Services Research, University of Southern Denmark, Odense Denmark Background Prognostic and predictive markers are needed for individualizing the treatment of colorectal cancer. Hypoxia-inducible factor 1α (HIF-1α) is a transcription-inducing factor...

  19. Erk1/2 but not PI3K pathway is required for neurotrophin 3-induced oligodendrocyte differentiation of post-natal neural stem cells

    Institute of Scientific and Technical Information of China (English)

    XinhuaHu; LuJin; LinyinFeng

    2005-01-01

    Neurotrophin 3 (NT3) induces mouse cortical stem cells to an asymmetric division from a symmetric division, suggesting that NT3 may work as an early differentiative signal for neural stem cells (NSCs). Here, using cultured post-natal hippocampal stem cells as a model, we demonstrated that NT3-stimulation causes NSCs to differentiate into oligodendrocyte precursors (OLPs) through an extracellular signal-related kinasel/2 (Erkl/2)-dependent pathway. Following the treatment of NT3 for 24h, NSCs differentiated into more OLPs and fewer neurons, whereas the proliferation and survival of OLPs were not affected. NT3 induced a series of intracellular responses including enhancement of phosphorylation of Erk 1/2 or Akt and increase of expression of oligodendrocyte lineage gene (Olig)-1, a transcriptional factor known to participate in oligodendrocyte development. Application of U0126, a specific inhibitor of MEK1/2 which are upstream to Erk1/2, blocked the phosphorylation of Erk1/2, suppressed the expression of Olig-1 and prevented NSC differentiation into OLPs in response to NT3 stimulation. Blockade of TrkC also inhibited the differentiation of NSCs to OLPs induced by NT3. However,administration of LY294002, an inhibitor of phosphatidylinositol 3 kinase (PI3K), blocked the phosphorylation of Akt but did not affect the effect of NT3 on the expression of Olig-1 and on NSC differentiation into OLPs. Taken together, these results suggest that NT3 induce NSCs to differentiate into OLPs by enhancing the expression of Olig-1 through an Erk1/2-dependent pathway.

  20. VGF (TLQP-62)-induced neurogenesis targets early phase neural progenitor cells in the adult hippocampus and requires glutamate and BDNF signaling.

    Science.gov (United States)

    Thakker-Varia, Smita; Behnke, Joseph; Doobin, David; Dalal, Vidhi; Thakkar, Keya; Khadim, Farah; Wilson, Elizabeth; Palmieri, Alicia; Antila, Hanna; Rantamaki, Tomi; Alder, Janet

    2014-05-01

    The neuropeptide VGF (non-acronymic), which has antidepressant-like effects, enhances adult hippocampal neurogenesis as well as synaptic activity and plasticity in the hippocampus, however the interaction between these processes and the mechanism underlying this regulation remain unclear. In this study, we demonstrate that VGF-derived peptide TLQP-62 specifically enhances the generation of early progenitor cells in nestin-GFP mice. Specifically, TLQP-62 significantly increases the number of Type 2a neural progenitor cells (NPCs) while reducing the number of more differentiated Type 3 cells. The effect of TLQP-62 on proliferation rather than differentiation was confirmed using NPCs in vitro; TLQP-62 but not scrambled peptide PEHN-62 increases proliferation in a cell line as well as in primary progenitors from adult hippocampus. Moreover, TLQP-62 but not scrambled peptide increases Cyclin D mRNA expression. The proliferation of NPCs induced by TLQP-62 requires synaptic activity, in particular through NMDA and metabotropic glutamate receptors. The activation of glutamate receptors by TLQP-62 activation induces phosphorylation of CaMKII through NMDA receptors and protein kinase D through metabotropic glutamate receptor 5 (mGluR5). Furthermore, pharmacological antagonists to CaMKII and PKD inhibit TLQP-62-induced proliferation of NPCs indicating that these signaling molecules downstream of glutamate receptors are essential for the actions of TLQP-62 on neurogenesis. We also show that TLQP-62 gradually activates Brain-Derived Neurotrophic Factor (BDNF)-receptor TrkB in vitro and that Trk signaling is required for TLQP-62-induced proliferation of NPCs. Understanding the precise molecular mechanism of how TLQP-62 influences neurogenesis may reveal mechanisms by which VGF-derived peptides act as antidepressant-like agents.

  1. Neural Induction, Neural Fate Stabilization, and Neural Stem Cells

    Directory of Open Access Journals (Sweden)

    Sally A. Moody

    2002-01-01

    Full Text Available The promise of stem cell therapy is expected to greatly benefit the treatment of neurodegenerative diseases. An underlying biological reason for the progressive functional losses associated with these diseases is the extremely low natural rate of self-repair in the nervous system. Although the mature CNS harbors a limited number of self-renewing stem cells, these make a significant contribution to only a few areas of brain. Therefore, it is particularly important to understand how to manipulate embryonic stem cells and adult neural stem cells so their descendants can repopulate and functionally repair damaged brain regions. A large knowledge base has been gathered about the normal processes of neural development. The time has come for this information to be applied to the problems of obtaining sufficient, neurally committed stem cells for clinical use. In this article we review the process of neural induction, by which the embryonic ectodermal cells are directed to form the neural plate, and the process of neural�fate stabilization, by which neural plate cells expand in number and consolidate their neural fate. We will present the current knowledge of the transcription factors and signaling molecules that are known to be involved in these processes. We will discuss how these factors may be relevant to manipulating embryonic stem cells to express a neural fate and to produce large numbers of neurally committed, yet undifferentiated, stem cells for transplantation therapies.

  2. Functional pathway mapping analysis for hypoxia-inducible factors.

    Science.gov (United States)

    Chuang, Chia-Sheng; Pai, Tun-Wen; Hu, Chin-Hua; Tzou, Wen-Shyong; Dah-Tsyr Chang, Margaret; Chang, Hao-Teng; Chen, Chih-Chia

    2011-06-20

    Hypoxia-inducible factors (HIFs) are transcription factors that play a crucial role in response to hypoxic stress in living organisms. The HIF pathway is activated by changes in cellular oxygen levels and has significant impacts on the regulation of gene expression patterns in cancer cells. Identifying functional conservation across species and discovering conserved regulatory motifs can facilitate the selection of reference species for empirical tests. This paper describes a cross-species functional pathway mapping strategy based on evidence of homologous relationships that employs matrix-based searching techniques for identifying transcription factor-binding sites on all retrieved HIF target genes. HIF-related orthologous and paralogous genes were mapped onto the conserved pathways to indicate functional conservation across species. Quantitatively measured HIF pathways are depicted in order to illustrate the extent of functional conservation. The results show that in spite of the evolutionary process of speciation, distantly related species may exhibit functional conservation owing to conservative pathways. The novel terms OrthRate and ParaRate are proposed to quantitatively indicate the flexibility of a homologous pathway and reveal the alternative regulation of functional genes. The developed functional pathway mapping strategy provides a bioinformatics approach for constructing biological pathways by highlighting the homologous relationships between various model species. The mapped HIF pathways were quantitatively illustrated and evaluated by statistically analyzing their conserved transcription factor-binding elements. hypoxia-inducible factor (HIF), hypoxia-response element (HRE), transcription factor (TF), transcription factor binding site (TFBS), KEGG (Kyoto Encyclopedia of Genes and Genomes), cross-species comparison, orthology, paralogy, functional pathway.

  3. HIV-1-infected and immune-activated macrophages induce astrocytic differentiation of human cortical neural progenitor cells via the STAT3 pathway.

    Directory of Open Access Journals (Sweden)

    Hui Peng

    Full Text Available Diminished adult neurogenesis is considered a potential mechanism in the pathogenesis of HIV-1-associated dementia (HAD. In HAD, HIV-1-infected and immune-activated brain mononuclear phagocytes (MP; perivascular macrophages and microglia drive central nervous system (CNS inflammation and may alter normal neurogenesis. We previously demonstrated HIV-1-infected and lipopolysaccharide (LPS activated monocyte-derived macrophages (MDM inhibit human neural progenitor cell (NPC neurogenesis, while enhancing astrogliogenesis through the secretion of the inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α, in vitro and in vivo. Here we further test the hypothesis that HIV-1-infected/activated MDM promote NPC astrogliogenesis via activation of the transcription factor signal transducer and activator of transcription 3 (STAT3, a critical factor for astrogliogenesis. Our results show that LPS-activated MDM-conditioned medium (LPS-MCM and HIV-infected/LPS-activated MDM-conditioned medium (LPS+HIV-MCM induced Janus kinase 1 (Jak1 and STAT3 activation. Induction of the Jak-STAT3 activation correlated with increased glia fibrillary acidic protein (GFAP expression, demonstrating an induction of astrogliogenesis. Moreover, STAT3-targeting siRNA (siSTAT3 decreased MCM-induced STAT3 activation and NPC astrogliogenesis. Furthermore, inflammatory cytokines (including IL-6, IL-1β and TNF-α produced by LPS-activated and/or HIV-1-infected MDM may contribute to MCM-induced STAT3 activation and astrocytic differentiation. These observations were confirmed in severe combined immunodeficient (SCID mice with HIV-1 encephalitis (HIVE. In HIVE mice, siRNA control (without target sequence, sicon pre-transfected NPCs injected with HIV-1-infected MDM showed more astrocytic differentiation and less neuronal differentiation of NPCs as compared to NPC injection alone. siSTAT3 abrogated HIV-1-infected MDM-induced astrogliogenesis of injected NPCs. Collectively, these

  4. Noncanonical transforming growth factor β (TGFβ) signaling in cranial neural crest cells causes tongue muscle developmental defects.

    Science.gov (United States)

    Iwata, Jun-ichi; Suzuki, Akiko; Pelikan, Richard C; Ho, Thach-Vu; Chai, Yang

    2013-10-11

    Microglossia is a congenital birth defect in humans and adversely impacts quality of life. In vertebrates, tongue muscle derives from the cranial mesoderm, whereas tendons and connective tissues in the craniofacial region originate from cranial neural crest (CNC) cells. Loss of transforming growth factor β (TGFβ) type II receptor in CNC cells in mice (Tgfbr2(fl/fl);Wnt1-Cre) causes microglossia due to a failure of cell-cell communication between cranial mesoderm and CNC cells during tongue development. However, it is still unclear how TGFβ signaling in CNC cells regulates the fate of mesoderm-derived myoblasts during tongue development. Here we show that activation of the cytoplasmic and nuclear tyrosine kinase 1 (ABL1) cascade in Tgfbr2(fl/fl);Wnt1-Cre mice results in a failure of CNC-derived cell differentiation followed by a disruption of TGFβ-mediated induction of growth factors and reduction of myogenic cell proliferation and differentiation activities. Among the affected growth factors, the addition of fibroblast growth factor 4 (FGF4) and neutralizing antibody for follistatin (FST; an antagonist of bone morphogenetic protein (BMP)) could most efficiently restore cell proliferation, differentiation, and organization of muscle cells in the tongue of Tgfbr2(fl/fl);Wnt1-Cre mice. Thus, our data indicate that CNC-derived fibroblasts regulate the fate of mesoderm-derived myoblasts through TGFβ-mediated regulation of FGF and BMP signaling during tongue development.

  5. Fgf signaling induces posterior neuroectoderm independently of Bmp signaling inhibition.

    NARCIS (Netherlands)

    Rentzsch, F.; Bakkers, J.; Kramer, C.; Hammerschmidt, M.

    2004-01-01

    Whereas according to the neural default model, neural specification is induced by extracellular inhibitors of bone morphogenetic proteins (Bmps), the role of fibroblast growth factors (Fgfs) during neural induction is heavily debated. Here, we show that, in zebrafish embryos, Bmps and Fgfs play diff

  6. Co-localization of neural cell adhesion molecule and fibroblast growth factor receptor 2 in early embryo development.

    Science.gov (United States)

    Vesterlund, Liselotte; Töhönen, Virpi; Hovatta, Outi; Kere, Juha

    2011-01-01

    During development there is a multitude of signaling events governing the assembly of the developing organism. Receptors for signaling molecules such as fibroblast growth factor receptor 2 (FGFR2) enable the embryo to communicate with the surrounding environment and activate downstream pathways. The neural cell adhesion molecule (NCAM) was first characterized as a cell adhesion molecule highly expressed in the nervous system, but recent studies have shown that it is also a signaling receptor. Using a novel single oocyte adaptation of the proximity ligation assay, we here show a close association between NCAM and FGFR2 in mouse oocytes and 2-cell embryos. Real-time PCR analyses revealed the presence of messenger RNA encoding key proteins in downstream signaling pathways in oocytes and early mouse embryos. In summary these findings show a co-localization of NCAM and FGFR2 in early vertebrate development with intracellular signaling pathways present to enable a cellular response.

  7. Increased expression of receptors for orexigenic factors in nodose ganglion of diet-induced obese rats.

    Science.gov (United States)

    Paulino, Gabriel; Barbier de la Serre, Claire; Knotts, Trina A; Oort, Pieter J; Newman, John W; Adams, Sean H; Raybould, Helen E

    2009-04-01

    The vagal afferent pathway is important in short-term regulation of food intake, and decreased activation of this neural pathway with long-term ingestion of a high-fat diet may contribute to hyperphagic weight gain. We tested the hypothesis that expression of genes encoding receptors for orexigenic factors in vagal afferent neurons are increased by long-term ingestion of a high-fat diet, thus supporting orexigenic signals from the gut. Obesity-prone (DIO-P) rats fed a high-fat diet showed increased body weight and hyperleptinemia compared with low-fat diet-fed controls and high-fat diet-induced obesity-resistant (DIO-R) rats. Expression of the type I cannabinoid receptor and growth hormone secretagogue receptor 1a in the nodose ganglia was increased in DIO-P compared with low-fat diet-fed controls or DIO-R rats. Shifts in the balance between orexigenic and anorexigenic signals within the vagal afferent pathway may influence food intake and body weight gain induced by high fat diets.

  8. Generation and gene expression profiling of 48 transcription-factor-inducible mouse embryonic stem cell lines

    Science.gov (United States)

    Yamamizu, Kohei; Sharov, Alexei A.; Piao, Yulan; Amano, Misa; Yu, Hong; Nishiyama, Akira; Dudekula, Dawood B.; Schlessinger, David; Ko, Minoru S. H.

    2016-01-01

    Mouse embryonic stem cells (ESCs) can differentiate into a wide range – and possibly all cell types in vitro, and thus provide an ideal platform to study systematically the action of transcription factors (TFs) in cell differentiation. Previously, we have generated and analyzed 137 TF-inducible mouse ESC lines. As an extension of this “NIA Mouse ESC Bank,” we generated and characterized 48 additional mouse ESC lines, in which single TFs in each line could be induced in a doxycycline-controllable manner. Together, with the previous ESC lines, the bank now comprises 185 TF-manipulable ESC lines (>10% of all mouse TFs). Global gene expression (transcriptome) profiling revealed that the induction of individual TFs in mouse ESCs for 48 hours shifts their transcriptomes toward specific differentiation fates (e.g., neural lineages by Myt1 Isl1, and St18; mesodermal lineages by Pitx1, Pitx2, Barhl2, and Lmx1a; white blood cells by Myb, Etv2, and Tbx6, and ovary by Pitx1, Pitx2, and Dmrtc2). These data also provide and lists of inferred target genes of each TF and possible functions of these TFs. The results demonstrate the utility of mouse ESC lines and their transcriptome data for understanding the mechanism of cell differentiation and the function of TFs. PMID:27150017

  9. Synergistic effects of sodium butyrate, a histone deacetylase inhibitor, on increase of neurogenesis induced by pyridoxine and increase of neural proliferation in the mouse dentate gyrus.

    Science.gov (United States)

    Yoo, Dae Young; Kim, Woosuk; Nam, Sung Min; Kim, Dae Won; Chung, Jin Young; Choi, Soo Young; Yoon, Yeo Sung; Won, Moo-Ho; Hwang, In Koo

    2011-10-01

    We previously observed that pyridoxine (vitamin B(6)) significantly increased cell proliferation and neuroblast differentiation without any neuronal damage in the hippocampus. In this study, we investigated the effects of sodium butyrate, a histone deacetylase (HDAC) inhibitor which serves as an epigenetic regulator of gene expression, on pyridoxine-induced neural proliferation and neurogenesis induced by the increase of neural proliferation in the mouse dentate gyrus. Sodium butyrate (300 mg/kg, subcutaneously), pyridoxine (350 mg/kg, intraperitoneally), or combination with sodium butyrate were administered to 8-week-old mice twice a day and once a day, respectively, for 14 days. The administration of sodium butyrate significantly increased acetyl-histone H3 levels in the dentate gyrus. Sodium butyrate alone did not show the significant increase of cell proliferation in the dentate gyrus. But, pyridoxine alone significantly increased cell proliferation. Sodium butyrate in combination with pyridoxine robustly enhanced cell proliferation and neurogenesis induced by the increase of neural proliferation in the dentate gyrus, showing that sodium butyrate treatment distinctively enhanced development of neuroblast dendrites. These results indicate that an inhibition of HDAC synergistically promotes neurogenesis induced by a pyridoxine and increase of neural proliferation.

  10. Method of Measurement of Capacitance and Dielectric Loss Factor Using Artificial Neural Networks

    OpenAIRE

    Roj Jerzy; Cichy Adam

    2015-01-01

    A novel method of dielectric loss factor measuring has been described. It is based on a quasi-balanced method for the capacitance measurement. These AC circuits allow to measure only one component of the impedance. However, after analyzing a quasi-balanced circuit's processing equation, it is possible to derive a novel method of dielectric loss factor measuring. Dielectric loss factor can be calculated after detuning the circuit from its quasi-equilibrium state. There are two possible ways of...

  11. Role of myeloid growth factors in chemotherapy induced neutropenia

    Directory of Open Access Journals (Sweden)

    Ravinutala Srinath Bharadwaj

    2016-10-01

    Full Text Available Neutropenia is a major dose limiting toxicity of many chemo therapeutic regimens. Haemopoietic colony - stimulating factors (CSFs have been shown to reduce the duration and severity of chemotherapy induced neutropenia (CIN and risk of febrile neutropenia. Supportive care with myeloid growth factors improve chemotherapy delivery by minimizing chemotherapy dose reductions or treatment delays by enabling the delivery of full dose chemotherapy (dose dense in short time intervals. The goal of this article is to give comprehensive review of current literature regarding medical practice guidelines and risk assessment models for appropriate use of myeloid growth factors and management of febrile neutropenia. [Int J Basic Clin Pharmacol 2016; 5(5.000: 1715-1721

  12. An artificial neural network prediction model of congenital heart disease based on risk factors

    Science.gov (United States)

    Li, Huixia; Luo, Miyang; Zheng, Jianfei; Luo, Jiayou; Zeng, Rong; Feng, Na; Du, Qiyun; Fang, Junqun

    2017-01-01

    Abstract An artificial neural network (ANN) model was developed to predict the risks of congenital heart disease (CHD) in pregnant women. This hospital-based case-control study involved 119 CHD cases and 239 controls all recruited from birth defect surveillance hospitals in Hunan Province between July 2013 and June 2014. All subjects were interviewed face-to-face to fill in a questionnaire that covered 36 CHD-related variables. The 358 subjects were randomly divided into a training set and a testing set at the ratio of 85:15. The training set was used to identify the significant predictors of CHD by univariate logistic regression analyses and develop a standard feed-forward back-propagation neural network (BPNN) model for the prediction of CHD. The testing set was used to test and evaluate the performance of the ANN model. Univariate logistic regression analyses were performed on SPSS 18.0. The ANN models were developed on Matlab 7.1. The univariate logistic regression identified 15 predictors that were significantly associated with CHD, including education level (odds ratio  = 0.55), gravidity (1.95), parity (2.01), history of abnormal reproduction (2.49), family history of CHD (5.23), maternal chronic disease (4.19), maternal upper respiratory tract infection (2.08), environmental pollution around maternal dwelling place (3.63), maternal exposure to occupational hazards (3.53), maternal mental stress (2.48), paternal chronic disease (4.87), paternal exposure to occupational hazards (2.51), intake of vegetable/fruit (0.45), intake of fish/shrimp/meat/egg (0.59), and intake of milk/soymilk (0.55). After many trials, we selected a 3-layer BPNN model with 15, 12, and 1 neuron in the input, hidden, and output layers, respectively, as the best prediction model. The prediction model has accuracies of 0.91 and 0.86 on the training and testing sets, respectively. The sensitivity, specificity, and Yuden Index on the testing set (training set) are 0.78 (0.83), 0.90 (0

  13. From cellular to chemical approach for acute neural and alternative options for age-induced functional diseases

    Institute of Scientific and Technical Information of China (English)

    Antonin; Bukovsky

    2015-01-01

    Endogenous "stem cell niche"(SCN) accompanying vessels contains immune system components which in vivo determine differentiation of multi potent stem cells toward proper cell types in given tissue. Combinations of sex steroids may represent novel chemical approach for neuronal areas of regenerative medicine,since they cause transformation of vascular smooth muscle stem cells into differentiating neuronal cells. Circulating sex steroids are present during pregnancy and can be utilized where needed,when various embryonic/fetal tissues develop from their stem cells. Utilization of induced regeneration of tissues(regenerative medicine) is expected being more effective in sudden failures of younger individuals carrying intact SCN,as compared to established chronic disorders caused by SCN alteration. An essential component of SCN are monocyte-derived cells exhibiting tissue-specific "stop effect"(SE) preventing,for instance,an aging of neuronal cells. Its alteration causes that implantation of neuronal stem cells will also result in their differentiation toward aging cells. When we repair the SE by supply of circulating mononuclear cells from young healthy individuals,we may be able to provide novel regenerative treatments of age-induced neural diseases by sex steroid combinations. Questions regarding some age-induced body alterations are also addressed.

  14. Disturbed apoptosis and cell proliferation in developing neuroepithelium of lumbo-sacral neural tubes in retinoic acid-induced spina bifida aperta in rat.

    Science.gov (United States)

    Wei, Xiaowei; Li, Hui; Miao, Jianing; Zhou, Fenghua; Liu, Bo; Wu, Di; Li, Shujing; Wang, Lili; Fan, Yang; Wang, Weilin; Yuan, Zhengwei

    2012-08-01

    Spina bifida is a complex congenital malformation resulting from failure of fusion in the spinal neural tube during embryogenesis. However, the cellular mechanism underlying spina bifida is not fully understood. Here, we investigated cell apoptosis in whole embryos and proliferation of neural progenitor cells in the spinal neural tube during neurulation in all-trans retinoic acid (atRA)-induced spina bifida in fetal rats. Cell apoptosis was assessed by TUNEL assay on whole-mount and serially sectioned samples of rat embryos with spina bifida. Cell proliferation of lumbo-sacral neural progenitor cells was assessed by staining for the mitotic marker Ki67 and pH3. We found an excess of apoptosis in the neuroepithelium of embryos with spina bifida, which became more marked as embryos progress from E11 to E13. Conversely, there was a reduction in cell proliferation in spina bifida embryos, with a progressively greater difference from controls with stage from E11 to 13. Thus, atRA-induced spina bifida in rat shows perturbed apoptosis and proliferation of neural progenitors in the lumbo-sacral spinal cord during embryonic development, which might contribute to the pathogenesis of spina bifida.

  15. The human factor: behavioral and neural correlates of humanized perception in moral decision making.

    Directory of Open Access Journals (Sweden)

    Jasminka Majdandžić

    Full Text Available The extent to which people regard others as full-blown individuals with mental states ("humanization" seems crucial for their prosocial motivation towards them. Previous research has shown that decisions about moral dilemmas in which one person can be sacrificed to save multiple others do not consistently follow utilitarian principles. We hypothesized that this behavior can be explained by the potential victim's perceived humanness and an ensuing increase in vicarious emotions and emotional conflict during decision making. Using fMRI, we assessed neural activity underlying moral decisions that affected fictitious persons that had or had not been experimentally humanized. In implicit priming trials, participants either engaged in mentalizing about these persons (Humanized condition or not (Neutral condition. In subsequent moral dilemmas, participants had to decide about sacrificing these persons' lives in order to save the lives of numerous others. Humanized persons were sacrificed less often, and the activation pattern during decisions about them indicated increased negative affect, emotional conflict, vicarious emotions, and behavioral control (pgACC/mOFC, anterior insula/IFG, aMCC and precuneus/PCC. Besides, we found enhanced effective connectivity between aMCC and anterior insula, which suggests increased emotion regulation during decisions affecting humanized victims. These findings highlight the importance of others' perceived humanness for prosocial behavior - with aversive affect and other-related concern when imagining harming more "human-like" persons acting against purely utilitarian decisions.

  16. Bystander Effect Fuels Human Induced Pluripotent Stem Cell-Derived Neural Stem Cells to Quickly Attenuate Early Stage Neurological Deficits After Stroke.

    Science.gov (United States)

    Eckert, Auston; Huang, Lei; Gonzalez, Rodolfo; Kim, Hye-Sun; Hamblin, Milton H; Lee, Jean-Pyo

    2015-07-01

    : Present therapies for stroke rest with tissue plasminogen activator (tPA), the sole licensed antithrombotic on the market; however, tPA's effectiveness is limited in that the drug not only must be administered less than 3-5 hours after stroke but often exacerbates blood-brain barrier (BBB) leakage and increases hemorrhagic incidence. A potentially promising therapy for stroke is transplantation of human induced pluripotent stem cell-derived neural stem cells (hiPSC-NSCs). To date, the effects of iPSCs on injuries that take place during early stage ischemic stroke have not been well studied. Consequently, we engrafted iPSC-NSCs into the ipsilesional hippocampus, a natural niche of NSCs, at 24 hours after stroke (prior to secondary BBB opening and when inflammatory signature is abundant). At 48 hours after stroke (24 hours after transplant), hiPSC-NSCs had migrated to the stroke lesion and quickly improved neurological function. Transplanted mice showed reduced expression of proinflammatory factors (tumor necrosis factor-α, interleukin 6 [IL-6], IL-1β, monocyte chemotactic protein 1, macrophage inflammatory protein 1α), microglial activation, and adhesion molecules (intercellular adhesion molecule 1, vascular cell adhesion molecule 1) and attenuated BBB damage. We are the first to report that engrafted hiPSC-NSCs rapidly improved neurological function (less than 24 hours after transplant). Rapid hiPSC-NSC therapeutic activity is mainly due to a bystander effect that elicits reduced inflammation and BBB damage. Clinically, cerebral vessel occlusion is rarely permanent because of spontaneous or thrombolytic therapy-mediated reperfusion. These results have clinical implications indicating a much extended therapeutic window for transplantation of human induced pluripotent stem cell-derived neural stem cells (hiPSC-NSCs; 24 hours after stroke as opposed to the 5-hour window with tissue plasminogen activator [tPA]). In addition, there is potential for a synergistic

  17. Noscapine induces apoptosis in human glioma cells by an apoptosis-inducing factor-dependent pathway.

    Science.gov (United States)

    Newcomb, Elizabeth W; Lukyanov, Yevgeniy; Smirnova, Iva; Schnee, Tona; Zagzag, David

    2008-07-01

    Previously, we identified noscapine as a small molecule inhibitor of the hypoxia-inducible factor-1 pathway in hypoxic human glioma cells and human umbilical vein endothelial cells. Noscapine is a nontoxic ingredient in cough medicine currently used in clinical trials for patients with non-Hodgkin's lymphoma or chronic lymphocytic leukemia to assess antitumor efficacy. Here, we have evaluated the sensitivity of four human glioma cell lines to noscapine-induced apoptosis. Noscapine was a potent inhibitor of proliferation and inducer of apoptosis. Induction of apoptosis was associated with activation of the c-jun N-terminal kinase signaling pathway concomitant with inactivation of the extracellular signal regulated kinase signaling pathway and phosphorylation of the antiapoptotic protein Bcl-2. Noscapine-induced apoptosis was associated with the release of mitochondrial proteins apoptosis-inducing factor (AIF) and/or cytochrome c. In some glioma cell lines, only AIF release occurred without cytochrome c release or poly (ADP-ribose) polymerase cleavage. Knock-down of AIF decreased noscapine-induced apoptosis. Our results suggest the potential importance of noscapine as a novel agent for use in patients with glioblastoma owing to its low toxicity profile and its potent anticancer activity.

  18. Perfluorooctane sulfonate induces neuronal and oligodendrocytic differentiation in neural stem cells and alters the expression of PPARγ in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wan Ibrahim, Wan Norhamidah, E-mail: hamidah@science.upm.edu.my [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Tofighi, Roshan, E-mail: Roshan.Tofighi@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Onishchenko, Natalia, E-mail: Natalia.Onishchenko@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Rebellato, Paola, E-mail: Paola.Rebellato@ki.se [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-17177 Stockholm (Sweden); Bose, Raj, E-mail: Raj.Bose@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Uhlén, Per, E-mail: Per.Uhlen@ki.se [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-17177 Stockholm (Sweden); Ceccatelli, Sandra, E-mail: Sandra.Ceccatelli@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden)

    2013-05-15

    Perfluorinated compounds are ubiquitous chemicals of major concern for their potential adverse effects on the human population. We have used primary rat embryonic neural stem cells (NSCs) to study the effects of perfluorooctane sulfonate (PFOS) on the process of NSC spontaneous differentiation. Upon removal of basic fibroblast growth factor, NSCs were exposed to nanomolar concentrations of PFOS for 48 h, and then allowed to differentiate for additional 5 days. Exposure to 25 or 50 nM concentration resulted in a lower number of proliferating cells and a higher number of neurite-bearing TuJ1-positive cells, indicating an increase in neuronal differentiation. Exposure to 50 nM also significantly increased the number of CNPase-positive cells, pointing to facilitation of oligodendrocytic differentiation. PPAR genes have been shown to be involved in PFOS toxicity. By q-PCR we detected an upregulation of PPARγ with no changes in PPARα or PPARδ genes. One of the downstream targets of PPARs, the mitochondrial uncoupling protein 2 (UCP2) was also upregulated. The number of TuJ1- and CNPase-positive cells increased after exposure to PPARγ agonist rosiglitazone (RGZ, 3 μM) and decreased after pre-incubation with the PPARγ antagonist GW9662 (5 μM). RGZ also upregulated the expression of PPARγ and UCP2 genes. Meanwhile GW9662 abolished the UCP2 upregulation and decreased Ca{sup 2+} activity induced by PFOS. Interestingly, a significantly higher expression of PPARγ and UCP3 genes was also detected in mouse neonatal brain after prenatal exposure to PFOS. These data suggest that PPARγ plays a role in the alteration of spontaneous differentiation of NSCs induced by nanomolar concentrations of PFOS. - Highlights: • PFOS decreases proliferation of neural stem cells (NSCs). • PFOS induces neuronal and oligodendrocytic differentiation in NSCs. • PFOS alters expression of PPARγ and UCP2 in vitro. • PFOS alters expression of PPARγ and UCP3 in vivo. • Block of PPAR

  19. Endothelin-1 induces connective tissue growth factor expression in cardiomyocytes.

    Science.gov (United States)

    Recchia, Anna Grazia; Filice, Elisabetta; Pellegrino, Daniela; Dobrina, Aldo; Cerra, Maria Carmela; Maggiolini, Marcello

    2009-03-01

    Endothelin (ET)-1 is a vasoconstrictor involved in cardiovascular diseases. Connective tissue growth factor/CCN2 (CTGF) is a fibrotic mediator overexpressed in human atherosclerotic lesions, myocardial infarction, and hypertension. In different cell types CTGF regulates cell proliferation/apoptosis, migration, and extracellular matrix (ECM) accumulation and plays important roles in angiogenesis, chondrogenesis, osteogenesis, tissue repair, cancer and fibrosis. In the present study, we investigated the ET-1 signaling which triggers CTGF expression in cultured adult mouse atrial-muscle HL-1 cells used as a model system. ET-1 activated the CTGF promoter and induced CTGF expression at both mRNA and protein levels. Real-time PCR analysis revealed CTGF induction also in isolated rat heart preparations perfused with ET-1. Several intracellular signals elicited by ET-1 via ET receptors and even Epidermal Growth Factor Receptor (EGFR) contributed to the up-regulation of CTGF, including ERK activation and induction of the AP-1 components c-fos and c-jun, as also evaluated by ChIP analysis. Moreover, in cells treated with ET-1 the expression of ECM component decorin was abolished by CTGF silencing, indicating that CTGF is involved in ET-1 induced ECM accumulation not only in a direct manner but also through downstream effectors. Collectively, our data indicate that CTGF could be a mediator of the profibrotic effects of ET-1 in cardiomyocytes. CTGF inhibitors should be considered in setting a comprehensive pharmacological approach towards ET-1 induced cardiovascular diseases.

  20. Factors Associated with Incidence of Induced Abortion in Hamedan, Iran.

    Science.gov (United States)

    Hosseini, Hatam; Erfani, Amir; Nojomi, Marzieh

    2017-05-01

    There is limited reliable information on abortion in Iran, where abortion is illegal and many women of reproductive age seek clandestine abortion to end their unintended pregnancy. This study aims to examine the determinants of induced abortion in the city of Hamedan, Iran. The study utilizes recent data from the 2015 Hamedan Survey of Fertility, conducted in a representative sample of 3,000 married women aged 15-49 years in the city of Hamedan, Iran. Binary logistic regression models are used to examine factors associated with the incidence of abortion. Overall, 3.8% of respondents reported having had an induced abortion in their life. Multivariate results showed that the incidence of abortion was strongly associated with women's education, type of contraceptive and family income level, after controlling for confounding factors. Women using long-acting contraceptive methods, those educated under high school diploma or postsecondary education, and those with high level of income were more likely to report having an induced abortion. The high incidence of abortion among less or more educated women and those with high income level signifies unmet family planning needs among these women, which must be addressed by focused reproductive health and family planning programs.

  1. Speech Sound Processing Deficits and Training-Induced Neural Plasticity in Rats with Dyslexia Gene Knockdown

    Science.gov (United States)

    Centanni, Tracy M.; Chen, Fuyi; Booker, Anne M.; Engineer, Crystal T.; Sloan, Andrew M.; Rennaker, Robert L.; LoTurco, Joseph J.; Kilgard, Michael P.

    2014-01-01

    In utero RNAi of the dyslexia-associated gene Kiaa0319 in rats (KIA-) degrades cortical responses to speech sounds and increases trial-by-trial variability in onset latency. We tested the hypothesis that KIA- rats would be impaired at speech sound discrimination. KIA- rats needed twice as much training in quiet conditions to perform at control levels and remained impaired at several speech tasks. Focused training using truncated speech sounds was able to normalize speech discrimination in quiet and background noise conditions. Training also normalized trial-by-trial neural variability and temporal phase locking. Cortical activity from speech trained KIA- rats was sufficient to accurately discriminate between similar consonant sounds. These results provide the first direct evidence that assumed reduced expression of the dyslexia-associated gene KIAA0319 can cause phoneme processing impairments similar to those seen in dyslexia and that intensive behavioral therapy can eliminate these impairments. PMID:24871331

  2. Experience-induced malleability in neural encoding of pitch, timbre, and timing.

    Science.gov (United States)

    Kraus, Nina; Skoe, Erika; Parbery-Clark, Alexandra; Ashley, Richard

    2009-07-01

    Speech and music are highly complex signals that have many shared acoustic features. Pitch, Timbre, and Timing can be used as overarching perceptual categories for describing these shared properties. The acoustic cues contributing to these percepts also have distinct subcortical representations which can be selectively enhanced or degraded in different populations. Musically trained subjects are found to have enhanced subcortical representations of pitch, timbre, and timing. The effects of musical experience on subcortical auditory processing are pervasive and extend beyond music to the domains of language and emotion. The sensory malleability of the neural encoding of pitch, timbre, and timing can be affected by lifelong experience and short-term training. This conceptual framework and supporting data can be applied to consider sensory learning of speech and music through a hearing aid or cochlear implant.

  3. Exaggerated haemodynamic and neural responses to involuntary contractions induced by whole-body vibration in normotensive obese versus lean women.

    Science.gov (United States)

    Dipla, Konstantina; Kousoula, Dimitra; Zafeiridis, Andreas; Karatrantou, Konstantina; Nikolaidis, Michalis G; Kyparos, Antonios; Gerodimos, Vassilis; Vrabas, Ioannis S

    2016-06-01

    What is the central question of this study? In obesity, the exaggerated blood pressure response to voluntary exercise is linked to hypertension, yet the mechanisms are not fully elucidated. We examined whether involuntary contractions elicit greater haemodynamic responses and altered neural control of blood pressure in normotensive obese versus lean women. What is the main finding and its importance? During involuntary contractions induced by whole-body vibration, there were augmented blood pressure and spontaneous baroreflex responses in obese compared with lean women. This finding is suggestive of an overactive mechanoreflex in the exercise-induced hypertensive response in obesity. Passive contractions did not elicit differential heart rate responses in obese compared with lean women, implying other mechanisms for the blunted heart rate response reported during voluntary exercise in obesity. In obesity, the exaggerated blood pressure (BP) response to exercise is linked to hypertension, yet the mechanisms are not fully elucidated. In this study, we examined whether involuntary mechanical oscillations, induced by whole-body vibration (WBV), elicit greater haemodynamic responses and altered neural control of BP in obese versus lean women. Twenty-two normotensive, premenopausal women (12 lean and 10 obese) randomly underwent a passive WBV (25 Hz) and a control protocol (similar posture without WVB). Beat-by-beat BP, heart rate, stroke volume, systemic vascular resistance, cardiac output, parasympathetic output (evaluated by heart rate variability) and spontaneous baroreceptor sensitivity (sBRS) were assessed. We found that during WBV, obese women exhibited an augmented systolic BP response compared with lean women that was correlated with body fat percentage (r = 0.77; P contractions did not elicit a differential magnitude of responses in heart rate, heart rate variability indices and systemic vascular resistance in obese versus lean women; however, they did result

  4. Development of the heated length to diameter correction factor on critical heat flux using the artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Ho; Baek, Won Pil; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Chun, Tae Hyun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    With using artificial neural networks (ANNs), an analytical study related to the heated length effect on critical heat flux (CHF) has been carried out to make an improvement of the CHF prediction accuracy based on local condition correlations or table. It has been carried out to suggest a feasible criterion of the threshold length-to-diameter (L/D) value in which heated length could affect CHF. And within the criterion, a L/D correction factor has been developed through conventional regression. In order to validate the developed L/D correction factor, CHF experiments for various heated lengths have been carried out under low and intermediate pressure conditions. The developed threshold L/D correlation provides a new feasible criterion of L/D threshold value. The developed correction factor gives a reasonable accuracy for the original database, showing the error of -2.18% for average and 27.75% for RMS, and promising results for new experimental data. 7 refs., 12 figs., 1 tab. (Author)

  5. Genetic risk factors of cisplatin induced ototoxicity in adult patients.

    Science.gov (United States)

    Talach, T; Rottenberg, J; Gal, B; Kostrica, R; Jurajda, M; Kocak, I; Lakomy, R; Vogazianos, E

    2016-01-01

    Ototoxicity is an important adverse effect of using Cisplatin (cis-diamminedichloroplatinum) (CDDP) as a form of chemotherapy. The clinical picture of CDDP induced ototoxicity includes perceptive hearing impairment (reversible or permanent) and tinnitus. Ototoxicity manifests with considerable variability between patients. The objective of this prospective study was to investigate a possible genetic background to this variability. We assessed ototoxicity induced by therapeutic doses of CDDP in adult patients with germinative testicular tumors, or other tumors treated with an identical CDDP dosage scheme. Audiological examination before, during and after the treatment has shown deterioration in hearing; first in the high-frequencies and with increased CDDP cumulative doses, impairment in other frequencies as well. Occurrence of tinnitus was not dependent on the administered dose of CDDP, or the other risk factors examined in this study. The association of CDDP induced ototoxicity with genetic polymorphisms in candidate genes was examined. Our study has demonstrated an association of early onset of CDDP induced ototoxicity with the presence of two copies of GSTT1 gene (p=0,009) and with T allele of rs9332377 polymorphism in COMT gene (p=0,001).

  6. Viral Carcinogenesis: Factors Inducing DNA Damage and Virus Integration

    Directory of Open Access Journals (Sweden)

    Yan Chen

    2014-10-01

    Full Text Available Viruses are the causative agents of 10%–15% of human cancers worldwide. The most common outcome for virus-induced reprogramming is genomic instability, including accumulation of mutations, aberrations and DNA damage. Although each virus has its own specific mechanism for promoting carcinogenesis, the majority of DNA oncogenic viruses encode oncogenes that transform infected cells, frequently by targeting p53 and pRB. In addition, integration of viral DNA into the human genome can also play an important role in promoting tumor development for several viruses, including HBV and HPV. Because viral integration requires the breakage of both the viral and the host DNA, the integration rate is believed to be linked to the levels of DNA damage. DNA damage can be caused by both endogenous and exogenous factors, including inflammation induced by either the virus itself or by co-infections with other agents, environmental agents and other factors. Typically, cancer develops years to decades following the initial infection. A better understanding of virus-mediated carcinogenesis, the networking of pathways involved in transformation and the relevant risk factors, particularly in those cases where tumorigenesis proceeds by way of virus integration, will help to suggest prophylactic and therapeutic strategies to reduce the risk of virus-mediated cancer.

  7. A hit and run approach to inducible direct reprogramming of astrocytes to neural stem cells

    Directory of Open Access Journals (Sweden)

    Maria ePoulou

    2016-04-01

    Full Text Available Temporal and spatial control of gene expression can be achieved using an inducible system as a fundamental tool for regulated transcription in basic, applied and eventually in clinical research. We describe a novel hit and run inducible direct reprogramming approach. In a single step, two days post-transfection, transiently transfected Sox2FLAG under the Leu3p-αIPM inducible control (iSox2 triggers the activation of endogenous Sox2, redirecting primary astrocytes into abundant distinct nestin-positive radial glia cells. This technique introduces a unique novel tool for safe, rapid and efficient reprogramming amendable to regenerative medicine.

  8. Physical and perceptual factors shape the neural mechanisms that integrate audiovisual signals in speech comprehension.

    Science.gov (United States)

    Lee, HweeLing; Noppeney, Uta

    2011-08-01

    Face-to-face communication challenges the human brain to integrate information from auditory and visual senses with linguistic representations. Yet the role of bottom-up physical (spectrotemporal structure) input and top-down linguistic constraints in shaping the neural mechanisms specialized for integrating audiovisual speech signals are currently unknown. Participants were presented with speech and sinewave speech analogs in visual, auditory, and audiovisual modalities. Before the fMRI study, they were trained to perceive physically identical sinewave speech analogs as speech (SWS-S) or nonspeech (SWS-N). Comparing audiovisual integration (interactions) of speech, SWS-S, and SWS-N revealed a posterior-anterior processing gradient within the left superior temporal sulcus/gyrus (STS/STG): Bilateral posterior STS/STG integrated audiovisual inputs regardless of spectrotemporal structure or speech percept; in left mid-STS, the integration profile was primarily determined by the spectrotemporal structure of the signals; more anterior STS regions discarded spectrotemporal structure and integrated audiovisual signals constrained by stimulus intelligibility and the availability of linguistic representations. In addition to this "ventral" processing stream, a "dorsal" circuitry encompassing posterior STS/STG and left inferior frontal gyrus differentially integrated audiovisual speech and SWS signals. Indeed, dynamic causal modeling and Bayesian model comparison provided strong evidence for a parallel processing structure encompassing a ventral and a dorsal stream with speech intelligibility training enhancing the connectivity between posterior and anterior STS/STG. In conclusion, audiovisual speech comprehension emerges in an interactive process with the integration of auditory and visual signals being progressively constrained by stimulus intelligibility along the STS and spectrotemporal structure in a dorsal fronto-temporal circuitry.

  9. Leukemia inhibitory factor (LIF) enhances MAP2 + and HUC/D + neurons and influences neurite extension during differentiation of neural progenitors derived from human embryonic stem cells.

    Science.gov (United States)

    Leukemia Inhibitory Factor (L1F), a member of the Interleukin 6 cytokine family, has a role in differentiation of Human Neural Progenitor (hNP) cells in vitro. hNP cells, derived from Human Embryonic Stem (hES) cells, have an unlimited capacity for self-renewal in monolayer cultu...

  10. Leukemia inhibitory factor (LIF) enhances MAP2 + and HUC/D + neurons and influences neurite extension during differentiation of neural progenitors derived from human embryonic stem cells.

    Science.gov (United States)

    Leukemia Inhibitory Factor (L1F), a member of the Interleukin 6 cytokine family, has a role in differentiation of Human Neural Progenitor (hNP) cells in vitro. hNP cells, derived from Human Embryonic Stem (hES) cells, have an unlimited capacity for self-renewal in monolayer cultu...

  11. The treatment of neural growth factor on 38 patients with vascular dementia%神经生长因子治疗血管性痴呆38例

    Institute of Scientific and Technical Information of China (English)

    李芳; 朱茜

    2003-01-01

    @@ BACKGROUND: Vascular dementia mainly is caused by is-chemic and hemorrhagic stroke, which often leads to progressive by-pomnesis. Neural growth factor(NGF) can prevent the functionaldeficits of study and memory and serves as a better way for curingvascular dementia.

  12. Predict typhoon-induced storm surge deviation in a principal component back-propagation neural network model

    Institute of Scientific and Technical Information of China (English)

    GUO Zhongyang; DAI Xiaoyan; LI Xiaodong; YE Shufeng

    2013-01-01

    To reduce typhoon-caused damages,numerical and empirical methods are often used to forecast typhoon storm surge.However,typhoon surge is a complex nonlinear process that is difficult to forecast accurately.We applied a principal component back-propagation neural network (PCBPNN) to predict the deviation in typhoon storm surge,in which data of the typhoon,upstream flood,and historical case studies were involved.With principal component analysis,15 input factors were reduced to five principal components,and the application of the model was improved.Observation data from Huangpu Park in Shanghai,China were used to test the feasibility of the model.The results indicate that the model is capable of predicting a 12-hour warning before a typhoon surge.

  13. A peptide derived from a trans-homophilic binding site in neural cell adhesion molecule induces neurite outgrowth and neuronal survival

    DEFF Research Database (Denmark)

    Køhler, Lene B; Soroka, Vladislav; Korshunova, Irina

    2010-01-01

    The neural cell adhesion molecule (NCAM) plays a key role in neural development, regeneration, and synaptic plasticity. The crystal structure of a fragment of NCAM comprising the three N-terminal immunoglobulin (Ig)-like modules indicates that the first and second Ig modules bind to each other...... module. It promoted survival of cultured cerebellar granule neurons (CGNs) and also induced neurite extension in cultures of dopaminergic neurons and CGNs; the latter effect was shown to be dependent on NCAM expression, indicating that plannexin mimics the neuritogenic effect of homophilic NCAM binding....

  14. Substrate-mediated reprogramming of human fibroblasts into neural crest stem-like cells and their applications in neural repair.

    Science.gov (United States)

    Tseng, Ting-Chen; Hsieh, Fu-Yu; Dai, Niann-Tzyy; Hsu, Shan-Hui

    2016-09-01

    Cell- and gene-based therapies have emerged as promising strategies for treating neurological diseases. The sources of neural stem cells are limited while the induced pluripotent stem (iPS) cells have risk of tumor formation. Here, we proposed the generation of self-renewable, multipotent, and neural lineage-related neural crest stem-like cells by chitosan substrate-mediated gene transfer of a single factor forkhead box D3 (FOXD3) for the use in neural repair. A simple, non-toxic, substrate-mediated method was applied to deliver the naked FOXD3 plasmid into human fibroblasts. The transfection of FOXD3 increased cell proliferation and up-regulated the neural crest marker genes (FOXD3, SOX2, and CD271), stemness marker genes (OCT4, NANOG, and SOX2), and neural lineage-related genes (Nestin, β-tubulin and GFAP). The expression levels of stemness marker genes and neural crest maker genes in the FOXD3-transfected fibroblasts were maintained until the fifth passage. The FOXD3 reprogrammed fibroblasts based on the new method significantly rescued the neural function of the impaired zebrafish. The chitosan substrate-mediated delivery of naked plasmid showed feasibility in reprogramming somatic cells. Particularly, the FOXD3 reprogrammed fibroblasts hold promise as an easily accessible cellular source with neural crest stem-like behavior for treating neural diseases in the future.

  15. Taurine Protected Against the Impairments of Neural Stem Cell Differentiated Neurons Induced by Oxygen-Glucose Deprivation.

    Science.gov (United States)

    Xiao, Bo; Liu, Huazhen; Gu, Zeyun; Liu, Sining; Ji, Cheng

    2015-11-01

    Cell transplantation of neural stem cells (NSCs) is a promising approach for neurological recovery both structurally and functionally. However, one big obstacle is to promote differentiation of NSCs into neurons and the followed maturation. In the present study, we aimed to investigate the protective effect of taurine on the differentiation of NSCs and subsequent maturation of their neuronal lineage, when exposed to oxygen-glucose deprivation (OGD). The results suggested that taurine (5-20 mM) promoted the viability and proliferation of NSCs, and it protected against 8 h of OGD induced impairments. Furthermore, 20 mM taurine promoted NSCs to differentiate into neurons after 7 days of culture, and it also protected against the suppressive impairments of 8 h of OGD. Consistently, taurine (20 mM) promoted the neurite sprouting and outgrowth of the NSC differentiated neurons after 14 days of differentiation, which were significantly inhibited by OGD (8 h). At D21, the mushroom spines and spine density were promoted or restored by 20 mM taurine. Taken together, the enhanced viability and proliferation of NSCs, more differentiated neurons and the promoted maturation of neurons by 20 mM taurine support its therapeutic application during stem cell therapy to enhance neurological recovery. Moreover, it protected against the impairments induced by OGD, which may highlight its role for a more direct therapeutic application especially in an ischemic stroke environment.

  16. Effects of craving behavioral intervention on neural substrates of cue-induced craving in Internet gaming disorder.

    Science.gov (United States)

    Zhang, Jin-Tao; Yao, Yuan-Wei; Potenza, Marc N; Xia, Cui-Cui; Lan, Jing; Liu, Lu; Wang, Ling-Jiao; Liu, Ben; Ma, Shan-Shan; Fang, Xiao-Yi

    2016-01-01

    Internet gaming disorder (IGD) is characterized by high levels of craving for online gaming and related cues. Since addiction-related cues can evoke increased activation in brain areas involved in motivational and reward processing and may engender gaming behaviors or trigger relapse, ameliorating cue-induced craving may be a promising target for interventions for IGD. This study compared neural activation between 40 IGD and 19 healthy control (HC) subjects during an Internet-gaming cue-reactivity task and found that IGD subjects showed stronger activation in multiple brain areas, including the dorsal striatum, brainstem, substantia nigra, and anterior cingulate cortex, but lower activation in the posterior insula. Furthermore, twenty-three IGD subjects (CBI + group) participated in a craving behavioral intervention (CBI) group therapy, whereas the remaining 17 IGD subjects (CBI - group) did not receive any intervention, and all IGD subjects were scanned during similar time intervals. The CBI + group showed decreased IGD severity and cue-induced craving, enhanced activation in the anterior insula and decreased insular connectivity with the lingual gyrus and precuneus after receiving CBI. These findings suggest that CBI is effective in reducing craving and severity in IGD, and it may exert its effects by altering insula activation and its connectivity with regions involved in visual processing and attention bias.

  17. Effects of craving behavioral intervention on neural substrates of cue-induced craving in Internet gaming disorder

    Directory of Open Access Journals (Sweden)

    Jin-Tao Zhang

    2016-01-01

    Full Text Available Internet gaming disorder (IGD is characterized by high levels of craving for online gaming and related cues. Since addiction-related cues can evoke increased activation in brain areas involved in motivational and reward processing and may engender gaming behaviors or trigger relapse, ameliorating cue-induced craving may be a promising target for interventions for IGD. This study compared neural activation between 40 IGD and 19 healthy control (HC subjects during an Internet-gaming cue-reactivity task and found that IGD subjects showed stronger activation in multiple brain areas, including the dorsal striatum, brainstem, substantia nigra, and anterior cingulate cortex, but lower activation in the posterior insula. Furthermore, twenty-three IGD subjects (CBI+ group participated in a craving behavioral intervention (CBI group therapy, whereas the remaining 17 IGD subjects (CBI− group did not receive any intervention, and all IGD subjects were scanned during similar time intervals. The CBI+ group showed decreased IGD severity and cue-induced craving, enhanced activation in the anterior insula and decreased insular connectivity with the lingual gyrus and precuneus after receiving CBI. These findings suggest that CBI is effective in reducing craving and severity in IGD, and it may exert its effects by altering insula activation and its connectivity with regions involved in visual processing and attention bias.

  18. Survival and differentiation of transplanted neural stem cells derived from human induced pluripotent stem cells in a rat stroke model.

    Science.gov (United States)

    Jensen, Matthew B; Yan, Hongmei; Krishnaney-Davison, Rajeev; Al Sawaf, Abdullah; Zhang, Su-Chun

    2013-05-01

    Although administration of various stem cells has shown promise in stroke models, neural stem cells (NSCs) derived from human induced pluripotent stem cells (iPSCs) have advantages over other cell types. We studied whether these cells could survive, differentiate, and improve stroke recovery in an ischemic stroke model. Human iPSCs were induced in vitro to an early NSC stage. One week after focal cerebral ischemia, 20 rats received cells or vehicle by intracerebral injection. Graft cell fate, infarct volume, and behavioral deficits were assessed. Graft cells were found in 8 of the transplanted rats (80%), with estimated mean graft cell numbers nearly double the amount transplanted 1 month later. Graft cells also expressed markers of NSCs in 5 rats (63%), neurons in all 8 rats (100%), rare astrocytes in 4 rats (50%), and signs of proliferation in 4 rats (50%), but no tumor formation was observed. Stroke volume and behavioral recovery were similar between the groups. To our knowledge, this is the first report of transplantation of NSCs derived from human iPSCs in a stroke model. Human iPSC-derived NSCs survived in the postischemic rat brain and appeared to differentiate, primarily into neurons. This cell transplantation approach for stroke appears to be feasible, but further optimization is needed. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  19. Reprogramming of mouse neural stem cells to induced pluripotent stem cells using Oct4 combined with microRNA

    Institute of Scientific and Technical Information of China (English)

    Qiuyue Yan; Jie Xu; Yanqiang Zhan; Zhouping Tang; Suming Zhang

    2011-01-01

    microRNA is important for maintaining characteristics of embryonic stem cells,and microRNA302a (MiR-302a) has been shown to exert important effects on cell reprogramming.Therefore,the present study used miR294 and miR302a,in combination with Oct4,to induce mouse neural stem cells (NSCs) into induced pluripotent stem (iPS) cells.Following identification of iPS cells,the effects of microRNA on cell reprogramming were analyzed.Results suggested that reprogramming efficiency with Oct4 + miR-294 + miR-302a was 7-fold greater than Oct4 alone (0.1% vs.0.014%).The iPS cells were undifferentiated and positive for alkaline phosphatase,SSEA-1,and Oct4.These findings demonstrated that microRNAs play an important role in cell reprogramming and provide a safe and efficient induction system for cellular reprogramming.

  20. A Double-Switch Cell Fusion-Inducible Transgene Expression System for Neural Stem Cell-Based Antiglioma Gene Therapy

    Directory of Open Access Journals (Sweden)

    Yumei Luo

    2015-01-01

    Full Text Available Recent progress in neural stem cell- (NSC- based tumor-targeted gene therapy showed that NSC vectors expressing an artificially engineered viral fusogenic protein, VSV-G H162R, could cause tumor cell death specifically under acidic tumor microenvironment by syncytia formation; however, the killing efficiency still had much room to improve. In the view that coexpression of another antitumoral gene with VSV-G can augment the bystander effect, a synthetic regulatory system that triggers transgene expression in a cell fusion-inducible manner has been proposed. Here we have developed a double-switch cell fusion-inducible transgene expression system (DoFIT to drive transgene expression upon VSV-G-mediated NSC-glioma cell fusion. In this binary system, transgene expression is coregulated by a glioma-specific promoter and targeting sequences of a microRNA (miR that is highly expressed in NSCs but lowly expressed in glioma cells. Thus, transgene expression is “switched off” by the miR in NSC vectors, but after cell fusion with glioma cells, the miR is diluted and loses its suppressive effect. Meanwhile, in the syncytia, transgene expression is “switched on” by the glioma-specific promoter. Our in vitro and in vivo experimental data show that DoFIT successfully abolishes luciferase reporter gene expression in NSC vectors but activates it specifically after VSV-G-mediated NSC-glioma cell fusion.

  1. Interactions of primary neuroepithelial progenitor and brain endothelial cells: distinct effect on neural progenitor maintenance and differentiation by soluble factors and direct contact

    Institute of Scientific and Technical Information of China (English)

    Miguel A Gama Sosa; Rita De Gasperi; Anne B Rocher; Gissel M Perez; Keila Simons; Daniel E Cruz; Patrick R Hof; Gregory A Elder

    2007-01-01

    Neurovascular interactions are crucial for the normal development of the central nervous system. To study such interactions in primary cultures, we developed a procedure to simultaneously isolate neural progenitor and endothelial cell fractions from embryonic mouse brains. Depending on the culture conditions endothelial cells were found to favor maintenance of the neuroprogenitor phenotype through the production of soluble factors, or to promote neuronal differentiation of neural progenitors through direct contact. These apparently opposing effects could reflect differential cellular interactions needed for the proper development of the brain.

  2. Transport and metabolism at blood-brain interfaces and in neural cells: relevance to bilirubin-induced encephalopathy

    Directory of Open Access Journals (Sweden)

    Silvia eGazzin

    2012-05-01

    Full Text Available Bilirubin, the end-product of heme catabolism, circulates in non pathological plasma mostly as a protein-bound species. When bilirubin concentration builds up, the free fraction of the molecule increases. Unbound bilirubin then diffuses across blood-brain interfaces into the brain, where it accumulates and exerts neurotoxic effects. In this classical view of bilirubin neurotoxicity, blood-brain interfaces act merely as structural barriers impeding the penetration of the pigment-bound carrier protein, and neural cells are considered as passive targets of its toxicity. Yet, the role of blood-brain interfaces in the occurrence of bilirubin encephalopathy appears more complex than being simple barriers to the diffusion of bilirubin, and neural cells such as astrocytes and neurons can play an active role in controlling the balance between the neuroprotective and neurotoxic effects of bilirubin. This article reviews the emerging in vivo and in vitro data showing that transport and metabolic detoxification mechanisms at the blood-brain and blood-CSF barriers may modulate bilirubin flux across both cellular interfaces, and that these protective functions can be affected in chronic hyperbilirubinemia. Then the in vivo and in vitro arguments in favor of the physiological antioxidant function of intracerebral bilirubin are presented, as well as with the potential role of transporters such as ABCC-1 and metabolizing enzymes such as cytochromes P-450 in setting the cerebral cell- and structure-specific toxicity of bilirubin following hyperbilirubinemia. The relevance of these data to the pathophysiology of bilirubin-induced neurological diseases is discussed.

  3. The frog vestibular system as a model for lesion-induced plasticity: basic neural principles and implications for posture control

    Directory of Open Access Journals (Sweden)

    Francois M Lambert

    2012-04-01

    Full Text Available Studies of behavioral consequences after unilateral labyrinthectomy have a long tradition in the quest of determining rules and limitations of the CNS to exert plastic changes that assist the recuperation from the loss of sensory inputs. Frogs were among the first animal models to illustrate general principles of regenerative capacity and reorganizational neural flexibility after a vestibular lesion. The continuous successful use of the latter animals is in part based on the easy access and identifiability of nerve branches to inner ear organs for surgical intervention, the possibility to employ whole brain preparations for in vitro studies and the limited degree of freedom of postural reflexes for quantification of behavioral impairments and subsequent improvements. Major discoveries that increased the knowledge of post-lesional reactive mechanisms in the central nervous system include alterations in vestibular commissural signal processing and activation of cooperative changes in excitatory and inhibitory inputs to disfacilitated neurons. Moreover, the observed increase of synaptic efficacy in propriospinal circuits illustrates the importance of limb proprioceptive inputs for postural recovery. Accumulated evidence suggests that the lesion-induced neural plasticity is not a goal-directed process that aims towards a meaningful restoration of vestibular reflexes but rather attempts a survival of those neurons that have lost their excitatory inputs. Accordingly, the reaction mechanism causes an improvement of some components but also a deterioration of other aspects as seen by spatio-temporally inappropriate vestibulo-motor responses, similar to the consequences of plasticity processes in various sensory systems and species. The generality of the findings indicate that frogs continue to form a highly amenable vertebrate model system for exploring molecular and physiological events during cellular and network reorganization after a loss of

  4. Estimation of seismic quality factor: Artificial neural networks and current approaches

    Science.gov (United States)

    Yıldırım, Eray; Saatçılar, Ruhi; Ergintav, Semih

    2017-01-01

    The aims of this study are to estimate soil attenuation using alternatives to traditional methods, to compare results of using these methods, and to examine soil properties using the estimated results. The performances of all methods, amplitude decay, spectral ratio, Wiener filter, and artificial neural network (ANN) methods, are examined on field and synthetic data with noise and without noise. High-resolution seismic reflection field data from Yeniköy (Arnavutköy, İstanbul) was used as field data, and 424 estimations of Q values were made for each method (1,696 total). While statistical tests on synthetic and field data are quite close to the Q value estimation results of ANN, Wiener filter, and spectral ratio methods, the amplitude decay methods showed a higher estimation error. According to previous geological and geophysical studies in this area, the soil is water-saturated, quite weak, consisting of clay and sandy units, and, because of current and past landslides in the study area and its vicinity, researchers reported heterogeneity in the soil. Under the same physical conditions, Q value calculated on field data can be expected to be 7.9 and 13.6. ANN models with various structures, training algorithm, input, and number of neurons are investigated. A total of 480 ANN models were generated consisting of 60 models for noise-free synthetic data, 360 models for different noise content synthetic data and 60 models to apply to the data collected in the field. The models were tested to determine the most appropriate structure and training algorithm. In the final ANN, the input vectors consisted of the difference of the width, energy, and distance of seismic traces, and the output was Q value. Success rate of both ANN methods with noise-free and noisy synthetic data were higher than the other three methods. Also according to the statistical tests on estimated Q value from field data, the method showed results that are more suitable. The Q value can be estimated

  5. Emotionally anesthetized: media violence induces neural changes during emotional face processing.

    Science.gov (United States)

    Stockdale, Laura A; Morrison, Robert G; Kmiecik, Matthew J; Garbarino, James; Silton, Rebecca L

    2015-10-01

    Media violence exposure causes increased aggression and decreased prosocial behavior, suggesting that media violence desensitizes people to the emotional experience of others. Alterations in emotional face processing following exposure to media violence may result in desensitization to others' emotional states. This study used scalp electroencephalography methods to examine the link between exposure to violence and neural changes associated with emotional face processing. Twenty-five participants were shown a violent or nonviolent film clip and then completed a gender discrimination stop-signal task using emotional faces. Media violence did not affect the early visual P100 component; however, decreased amplitude was observed in the N170 and P200 event-related potentials following the violent film, indicating that exposure to film violence leads to suppression of holistic face processing and implicit emotional processing. Participants who had just seen a violent film showed increased frontal N200/P300 amplitude. These results suggest that media violence exposure may desensitize people to emotional stimuli and thereby require fewer cognitive resources to inhibit behavior. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  6. A Sensitive and Specific Neural Signature for Picture-Induced Negative Affect.

    Directory of Open Access Journals (Sweden)

    Luke J Chang

    2015-06-01

    Full Text Available Neuroimaging has identified many correlates of emotion but has not yet yielded brain representations predictive of the intensity of emotional experiences in individuals. We used machine learning to identify a sensitive and specific signature of emotional responses to aversive images. This signature predicted the intensity of negative emotion in individual participants in cross validation (n =121 and test (n = 61 samples (high-low emotion = 93.5% accuracy. It was unresponsive to physical pain (emotion-pain = 92% discriminative accuracy, demonstrating that it is not a representation of generalized arousal or salience. The signature was comprised of mesoscale patterns spanning multiple cortical and subcortical systems, with no single system necessary or sufficient for predicting experience. Furthermore, it was not reducible to activity in traditional "emotion-related" regions (e.g., amygdala, insula or resting-state networks (e.g., "salience," "default mode". Overall, this work identifies differentiable neural components of negative emotion and pain, providing a basis for new, brain-based taxonomies of affective processes.

  7. Adhesion modification of neural stem cells induced by nanoscale ripple patterns

    Science.gov (United States)

    Pedraz, P.; Casado, S.; Rodriguez, V.; Giordano, M. C.; Buatier de Mongeot, F.; Ayuso-Sacido, A.; Gnecco, E.

    2016-03-01

    We have studied the influence of anisotropic nanopatterns (ripples) on the adhesion and morphology of mouse neural stem cells (C17.2) on glass substrates using cell viability assay, optical microscopy and atomic force microscopy. The ripples were produced by defocused ion beam sputtering with inert Ar ions, which physically remove atoms from the surface at the energy of 800 eV. The ripple periodicity (∼200 nm) is comparable to the thickness of the cytoplasmatic microspikes (filopodia) which link the stem cells to the substrate. All methods show that the cell adhesion is significantly lowered compared to the same type of cells on flat glass surfaces. Furthermore, the AFM analysis reveals that the filopodia tend to be trapped parallel or perpendicular to the ripples, which limits the spreading of the stem cell on the rippled substrate. This opens the perspective of controlling the micro-adhesion of stem cells and the orientation of their filopodia by tuning the anisotropic substrate morphology without chemical reactions occurring at the surface.

  8. The hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia

    Science.gov (United States)

    Zhang, Qian; Doucet, Michele; Tomlinson, Ryan E; Han, Xiaobin; Quarles, L Darryl; Collins, Michael T; Clemens, Thomas L

    2016-01-01

    Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 (FGF23) by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures. Recent studies have implicated the hypoxia-inducible factor-1α (HIF-1α) in other phosphate wasting disorders caused by elevated FGF23, including X-linked hypophosphatemic rickets and autosomal dominant hypophosphatemia. Here we provide evidence that HIF-1α mediates aberrant FGF23 in TIO by transcriptionally activating its promoter. Immunohistochemical studies in phosphaturic mesenchymal tumors resected from patients with documented TIO showed that HIF-1α and FGF23 were co-localized in spindle-shaped cells adjacent to blood vessels. Cultured tumor tissue produced high levels of intact FGF23 and demonstrated increased expression of HIF-1α protein. Transfection of MC3T3-E1 and Saos-2 cells with a HIF-1α expression construct induced the activity of a FGF23 reporter construct. Prior treatment of tumor organ cultures with HIF-1α inhibitors decreased HIF-1α and FGF23 protein accumulation and inhibited HIF-1α-induced luciferase reporter activity in transfected cells. Chromatin immunoprecipitation assays confirmed binding to a HIF-1α consensus sequence within the proximal FGF23 promoter, which was eliminated by treatment with a HIF-1α inhibitor. These results show for the first time that HIF-1α is a direct transcriptional activator of FGF23 and suggest that upregulation of HIF-1α activity in TIO contributes to the aberrant FGF23 production in these patients. PMID:27468359

  9. Prediction Effects of Personal, Psychosocial, and Occupational Risk Factors on Low Back Pain Severity Using Artificial Neural Networks Approach in Industrial Workers.

    Science.gov (United States)

    Darvishi, Ebrahim; Khotanlou, Hassan; Khoubi, Jamshid; Giahi, Omid; Mahdavi, Neda

    2017-07-21

    This study aimed to provide an empirical model of predicting low back pain (LBP) by considering the occupational, personal, and psychological risk factor interactions in workers population employed in industrial units using an artificial neural networks approach. A total of 92 workers with LBP as the case group and 68 healthy workers as a control group were selected in various industrial units with similar occupational conditions. The demographic information and personal, occupational, and psychosocial factors of the participants were collected via interview, related questionnaires, consultation with occupational medicine, and also the Rapid Entire Body Assessment worksheet and National Aeronautics and Space Administration Task Load Index software. Then, 16 risk factors for LBP were used as input variables to develop the prediction model. Networks with various multilayered structures were developed using MATLAB. The developed neural networks with 1 hidden layer and 26 neurons had the least error of classification in both training and testing phases. The mean of classification accuracy of the developed neural networks for the testing and training phase data were about 88% and 96%, respectively. In addition, the mean of classification accuracy of both training and testing data was 92%, indicating much better results compared with other methods. It appears that the prediction model using the neural network approach is more accurate compared with other applied methods. Because occupational LBP is usually untreatable, the results of prediction may be suitable for developing preventive strategies and corrective interventions. Copyright © 2017. Published by Elsevier Inc.

  10. Platelet-Released Growth Factors Induce Differentiation of Primary Keratinocytes

    Directory of Open Access Journals (Sweden)

    Andreas Bayer

    2017-01-01

    Full Text Available Autologous thrombocyte concentrate lysates, for example, platelet-released growth factors, (PRGFs or their clinically related formulations (e.g., Vivostat PRF® came recently into the physicians’ focus as they revealed promising effects in regenerative and reparative medicine such as the support of healing of chronic wounds. To elucidate the underlying mechanisms, we analyzed the influence of PRGF and Vivostat PRF on human keratinocyte differentiation in vitro and on epidermal differentiation status of skin wounds in vivo. Therefore, we investigated the expression of early (keratin 1 and keratin 10 and late (transglutaminase-1 and involucrin differentiation markers. PRGF treatment of primary human keratinocytes decreased keratin 1 and keratin 10 gene expression but induced involucrin and transglutaminase-1 gene expression in an epidermal growth factor receptor- (EGFR- dependent manner. In concordance with these results, microscopic analyses revealed that PRGF-treated human keratinocytes displayed morphological features typical of keratinocytes undergoing terminal differentiation. In vivo treatment of artificial human wounds with Vivostat PRF revealed a significant induction of involucrin and transglutaminase-1 gene expression. Together, our results indicate that PRGF and Vivostat PRF induce terminal differentiation of primary human keratinocytes. This potential mechanism may contribute to the observed beneficial effects in the treatment of hard-to-heal wounds with autologous thrombocyte concentrate lysates in vivo.

  11. Placental Induced Growth Factor (PIGf) in Coronary Artery Disease

    Science.gov (United States)

    Sundaresan, Alamelu; Carabello, Blaise; Mehta, Satish; Schlegel, Todd; Pellis, Neal; Ott, Mark; Pierson, Duane

    2010-01-01

    Our previous studies on normal human lymphocytes have shown a five-fold increase (p less than 0.001) in angiogenic inducers such as Placental Induced Growth Factor (PIGf) in physiologically stressful environments such as modeled microgravity, a space analog. This suggests de-regulation of cardiovascular signalling pathways indicated by upregulation of PIGf. In the current study, we measured PIGf in the plasma of 33 patients with and without coronary artery disease (CAD) to investigate whether such disease is associated with increased levels of PIGf. A control consisting of 31 sex matched apparently healthy subjects was also included in the study. We observed that the levels of PIGf in CAD patients were significantly increased compared to those in healthy control subjects (p less than 0.001) and usually increased beyond the clinical threshold level (greater than 27ng/L). The mechanisms leading to up-regulation of angiogenic factors and the adaptation of organisms to stressful environments such as isolation, high altitude, hypoxia, ischemia, microgravity, increased radiation, etc are presently unknown and require further investigation in spaceflight and these other physiologically stressed environments.

  12. Platelet-Activating Factor Induces Th17 Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Anne-Marie Drolet

    2011-01-01

    Full Text Available Th17 cells have been implicated in a number of inflammatory and autoimmune diseases. The phospholipid mediator platelet-activating factor (PAF is found in increased concentrations in inflammatory lesions and has been shown to induce IL-6 production. We investigated whether PAF could affect the development of Th17 cells. Picomolar concentrations of PAF induced IL-23, IL-6, and IL-1β expression in monocyte-derived Langerhans cells (LCs and in keratinocytes. Moreover, when LC were pretreated with PAF and then cocultured with anti-CD3- and anti-CD28-activated T cells, the latter developed a Th17 phenotype, with a significant increase in the expression of the transcriptional regulator RORγt and enhanced expression of IL-17, IL-21, and IL-22. PAF-induced Th17 development was prevented by the PAF receptor antagonist WEB2086 and by neutralizing antibodies to IL-23 and IL-6R. This may constitute a previously unknown stimulus for the development and persistence of inflammatory processes that could be amenable to pharmacologic intervention.

  13. The neural control of bimanual movements in the elderly: Brain regions exhibiting age-related increases in activity, frequency-induced neural modulation, and task-specific compensatory recruitment.

    Science.gov (United States)

    Goble, Daniel J; Coxon, James P; Van Impe, Annouchka; De Vos, Jeroen; Wenderoth, Nicole; Swinnen, Stephan P

    2010-08-01

    Coordinated hand use is an essential component of many activities of daily living. Although previous studies have demonstrated age-related behavioral deficits in bimanual tasks, studies that assessed the neural basis underlying such declines in function do not exist. In this fMRI study, 16 old and 16 young healthy adults performed bimanual movements varying in coordination complexity (i.e., in-phase, antiphase) and movement frequency (i.e., 45, 60, 75, 90% of critical antiphase speed) demands. Difficulty was normalized on an individual subject basis leading to group performances (measured by phase accuracy/stability) that were matched for young and old subjects. Despite lower overall movement frequency, the old group "overactivated" brain areas compared with the young adults. These regions included the supplementary motor area, higher order feedback processing areas, and regions typically ascribed to cognitive functions (e.g., inferior parietal cortex/dorsolateral prefrontal cortex). Further, age-related increases in activity in the supplementary motor area and left secondary somatosensory cortex showed positive correlations with coordinative ability in the more complex antiphase task, suggesting a compensation mechanism. Lastly, for both old and young subjects, similar modulation of neural activity was seen with increased movement frequency. Overall, these findings demonstrate for the first time that bimanual movements require greater neural resources for old adults in order to match the level of performance seen in younger subjects. Nevertheless, this increase in neural activity does not preclude frequency-induced neural modulations as a function of increased task demand in the elderly.

  14. Notch signaling induces retinal stem-like properties in perinatal neural retina progenitors and promotes symmetric divisions in adult retinal stem cells.

    Science.gov (United States)

    Balenci, Laurent; van der Kooy, Derek

    2014-02-01

    Understanding the mechanisms regulating retinal stem cell (RSC) activity is fundamental for future stem cell-based therapeutic purposes. By combining gain and loss of function approaches, we addressed whether Notch signaling may play a selective role in retinal stem versus retinal progenitor cells in both developing and adult eyes. Inhibition of either Notch or fibroblast growth factor signaling reduced proliferation of retinal stem and retinal progenitor cells, and inhibited RSC self-renewal. Conversely, exogenous Delta-like 3 and direct intrinsic Notch activation stimulated expansionary symmetric divisions in adult RSCs with the concomitant upregulation of Hes5. Knocking down Hes5 expression specifically decreased the numbers, but not the diameters, of adult RSC primary spheres, indicating that HES5 is the downstream effector of Notch receptor in controlling adult RSC proliferation. In addition, constitutive Notch activation induced retinal stem-like asymmetric self-renewal properties, with no expansion (no symmetrical division) in perinatal neural retina progenitor cells. These findings highlight central roles of Notch signaling activity in regulating the modes of division of retinal stem and retinal progenitor cells.

  15. The neural cell adhesion molecule-derived peptide, FGL, attenuates lipopolysaccharide-induced changes in glia in a CD200-dependent manner

    DEFF Research Database (Denmark)

    Cox, F F; Berezin, V; Bock, E

    2013-01-01

    Fibroblast growth loop (FGL) is a neural cell adhesion molecule (NCAM)-mimetic peptide that mimics the interaction of NCAM with fibroblast growth factor receptor (FGFR). FGL increases neurite outgrowth and promotes neuronal survival in vitro, and it has also been shown to have neuroprotective eff...

  16. Pyrolysed 3D-Carbon Scaffolds Induce Spontaneous Differentiation of Human Neural Stem Cells and Facilitate Real-Time Dopamine Detection

    NARCIS (Netherlands)

    Amato, Letizia; Heiskanen, Arto; Caviglia, Claudia; Shah, Fozia; Zor, Kinga; Skolimowski, Maciej; Madou, Marc; Gammelgaard, Lauge; Hansen, Rasmus; Seiz, Emma G.; Ramos, Milagros; Ramos Moreno, Tania; Martinez-Serrano, Alberto; Keller, Stephan S.; Emneus, Jenny

    2014-01-01

    Structurally patterned pyrolysed three-dimensional carbon scaffolds (p3D-carbon) are fabricated and applied for differentiation of human neural stem cells (hNSCs) developed for cell replacement therapy and sensing of released dopamine. In the absence of differentiation factors (DF) the pyrolysed car

  17. Deriving amplification factors from simple site parameters using generalized regression neural networks: implications for relevant site proxies

    Science.gov (United States)

    Boudghene Stambouli, Ahmed; Zendagui, Djawad; Bard, Pierre-Yves; Derras, Boumédiène

    2017-07-01

    Most modern seismic codes account for site effects using an amplification factor (AF) that modifies the rock acceleration response spectra in relation to a "site condition proxy," i.e., a parameter related to the velocity profile at the site under consideration. Therefore, for practical purposes, it is interesting to identify the site parameters that best control the frequency-dependent shape of the AF. The goal of the present study is to provide a quantitative assessment of the performance of various site condition proxies to predict the main AF features, including the often used short- and mid-period amplification factors, Fa and Fv, proposed by Borcherdt (in Earthq Spectra 10:617-653, 1994). In this context, the linear, viscoelastic responses of a set of 858 actual soil columns from Japan, the USA, and Europe are computed for a set of 14 real accelerograms with varying frequency contents. The correlation between the corresponding site-specific average amplification factors and several site proxies (considered alone or as multiple combinations) is analyzed using the generalized regression neural network (GRNN). The performance of each site proxy combination is assessed through the variance reduction with respect to the initial amplification factor variability of the 858 profiles. Both the whole period range and specific short- and mid-period ranges associated with the Borcherdt factors Fa and Fv are considered. The actual amplification factor of an arbitrary soil profile is found to be satisfactorily approximated with a limited number of site proxies (4-6). As the usual code practice implies a lower number of site proxies (generally one, sometimes two), a sensitivity analysis is conducted to identify the "best performing" site parameters. The best one is the overall velocity contrast between underlying bedrock and minimum velocity in the soil column. Because these are the most difficult and expensive parameters to measure, especially for thick deposits, other

  18. Neural correlates of heterotopic facilitation induced after high frequency electrical stimulation of nociceptive pathways

    NARCIS (Netherlands)

    Broeke, E.N. van den; Heck, C.H. van; Rijn, C.M. van; Wilder-Smith, O.H.G.

    2011-01-01

    Background High frequency electrical stimulation (HFS) of primary nociceptive afferents in humans induce a heightened sensitivity in the surrounding non-stimulated skin area. Several studies suggest that this heterotopic effect is the result of central (spinal) plasticity. The aim of this study is t

  19. A Novel in Vitro Analog Expressing Learning-Induced Cellular Correlates in Distinct Neural Circuits

    Science.gov (United States)

    Weisz, Harris A.; Wainwright, Marcy L.; Mozzachiodi, Riccardo

    2017-01-01

    When presented with noxious stimuli, "Aplysia" exhibits concurrent sensitization of defensive responses, such as the tail-induced siphon withdrawal reflex (TSWR) and suppression of feeding. At the cellular level, sensitization of the TSWR is accompanied by an increase in the excitability of the tail sensory neurons (TSNs) that elicit the…

  20. Chronic Restraint Stress Induces an Isoform-Specific Regulation on the Neural Cell Adhesion Molecule in the Hippocampus

    Science.gov (United States)

    Touyarot, K.; Sandi, C.

    2002-01-01

    Existing evidence indicates that 21-days exposure of rats to restraint stress induces dendritic atrophy in pyramidal cells of the hippocampus. This phenomenon has been related to altered performance in hippocampal-dependent learning tasks. Prior studies have shown that hippocampal expression of cell adhesion molecules is modified by such stress treatment, with the neural cell adhesion molecule (NCAM) decreasing and L1 increasing, their expression, at both the mRNA and protein levels. Given that NCAM comprises several isoforms, we investigated here whether chronic stress might differentially affect the expression of the three major isoforms (NCAM-120, NCAM-140, NCAM-180) in the hippocampus. In addition, as glucocorticoids have been implicated in the deleterious effects induced by chronic stress, we also evaluated plasma corticosterone levels and the hippocampal expression of the corticosteroid mineralocorticoid receptor (MR) and glucocorticoid receptor (GR). The results showed that the protein concentration of the NCAM-140 isoform decreased in the hippoampus of stressed rats. This effect was isoform-specific, because NCAM-120 and NCAM-180 levels were not significantly modified. In addition, whereas basal levels of plasma corticosterone tended to be increased, MR and GR concentrations were not significantly altered. Although possible changes in NCAM-120, NCAM-180 and corticosteroid receptors at earlier time points of the stress period cannot be ignored; this study suggests that a down-regulation of NCAM-140 might be implicated in the structural alterations consistently shown to be induced in the hippocampus by chronic stress exposure. As NCAM-140 is involved in cell-cell adhesion and neurite outgrowth, these findings suggest that this molecule might be one of the molecular mechanisms involved in the complex interactions among neurodegeneration-related events. PMID:12757368

  1. A neural flow estimator

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Harald Holger; Bogason, Gudmundur; Bruun, Erik

    1995-01-01

    This paper proposes a new way to estimate the flow in a micromechanical flow channel. A neural network is used to estimate the delay of random temperature fluctuations induced in a fluid. The design and implementation of a hardware efficient neural flow estimator is described. The system...... is implemented using switched-current technique and is capable of estimating flow in the μl/s range. The neural estimator is built around a multiplierless neural network, containing 96 synaptic weights which are updated using the LMS1-algorithm. An experimental chip has been designed that operates at 5 V...

  2. Di-(2-ethylhexyl Phthalate-Induced Hippocampus-Derived Neural Stem Cells Proliferation

    Directory of Open Access Journals (Sweden)

    Alireza Abdanipour

    2017-01-01

    Full Text Available The brain and spinal cord have a limited capacity for self-repair under damaged conditions. One of the best options to overcome these limitations involves the use of phytochemicals as potential therapeutic agents. In this study, we have aimed to investigate the effects of di-(2-ethylhexyl phthalate (DEHP on hippocampus-derived neural stem cells (NSCs proliferation to search phytochemical candidates for possible treatment of neurological diseases using endogenous capacity. In this experimental study, neonatal rat hippocampus-derived NSCs were cultured and treated with various concentrations of DEHP (0, 100, 200, 400 and 600 µM and Cirsium vulgare (C. vulgare hydroethanolic extract (0, 200, 400, 600, 800 and 1000 µg/ml for 48 hours under in vitro conditions. Cell proliferation rates and quantitative Sox2 gene expression were evaluated using MTT assay and real-time reverse transcription polymerase chain reaction (RT-PCR. We observed the highest average growth rate in the 400 µM DEHP and 800 µg/ml C. vulgare extract treated groups. Sox2 expression in the DEHP-treated NSCs significantly increased compared to the control group. Gas chromatography/mass spectrometry (GC/ MS results demonstrated that the active ingredients that naturally occurred in the C. vulgare hydroethanolic extract were 2-ethyl-1-hexanamine, n-heptacosane, 1-cyclopentanecarboxylic acid, 1-heptadecanamine, 2,6-octadien-1-ol,2,6,10,14,18,22-tetracosahexaene, and DEHP. DEHP profoundly stimulated NSCs proliferation through Sox2 gene overexpression. These results provide and opportunity for further use of the C. vulgure phytochemicals for prevention and/or treatment of neurological diseases via phytochemical mediated-proliferation of endogenous adult NSCs.

  3. Japanese encephalitis virus induce immuno-competency in neural stem/progenitor cells.

    Directory of Open Access Journals (Sweden)

    Sulagna Das

    Full Text Available BACKGROUND: The low immunogenicity of neural stem/progenitor cells (NSPCs coupled with negligible expression of MHC antigens has popularized their use in transplantation medicine. However, in an inflammatory environment, the NSPCs express costimulatory molecules and MHC antigens, and also exhibit certain immunomodulatory functions. Since NSPCs are the cellular targets in a number of virus infections both during postnatal and adult stages, we wanted to investigate the immunological properties of these stem cells in response to viral pathogen. METHODOLOGY/PRINCIPAL FINDINGS: We utilized both in vivo mouse model and in vitro neurosphere model of Japanese encephalitis virus (JEV infection for the study. The NSPCs residing in the subventricular zone of the infected brains showed prominent expression of MHC-I and costimulatory molecules CD40, CD80, and CD86. Using Flow cytometry and fluorescence microscopy, we observed increased surface expression of co-stimulatory molecule and MHC class I antigen in NSPCs upon progressive JEV infection in vitro. Moreover, significant production of pro-inflammatory cyto/chemokines was detected in JEV infected NSPCs by Cytokine Bead Array analysis. Interestingly, NSPCs were capable of providing functional costimulation to allogenic T cells and JEV infection resulted in increased proliferation of allogenic T cells, as detected by Mixed Lymphocyte reaction and CFSE experiments. We also report IL-2 production by NSPCs upon JEV infection, which possibly provides mitogenic signals to T cells and trigger their proliferation. CONCLUSION/SIGNIFICANCE: The in vivo and in vitro findings clearly indicate the development of immunogenicity in NSPCs following progressive JEV infection, in our case, JEV infection. Following a neurotropic virus infection, NSPCs possibly behave as immunogenic cells and contribute to both the innate and adaptive immune axes. The newly discovered immunological properties of NSPCs may have implications in

  4. Neural Crest Migration and Survival Are Susceptible to Morpholino-Induced Artifacts

    Science.gov (United States)

    Jette, Cicely A.

    2016-01-01

    The neural crest (NC) is a stem cell-like embryonic population that is essential for generating and patterning the vertebrate body, including the craniofacial skeleton and peripheral nervous system. Defects in NC development underlie many birth defects and contribute to formation of some of the most malignant cancers in humans, such as melanoma and neuroblastoma. For these reasons, significant research efforts have been expended to identify genes that control NC development, as it is expected to lead to a deeper understanding of the genetic mechanisms controlling vertebrate development and identify new treatments for NC-derived diseases and cancers. However, a number of inconsistencies regarding gene function during NC development have emerged from comparative analyses of gene function between mammalian and non-mammalian systems (chick, frog, zebrafish). This poses a significant barrier to identification of single genes and/or redundant pathways to target in NC diseases. Here, we determine whether technical differences, namely morpholino-based approaches used in non-mammalian systems, could contribute to these discrepancies, by examining the extent to which NC phenotypes in fascin1a (fscn1a) morphant embryos are similar to or different from fscn1a null mutants in zebrafish. Analysis of fscn1a morphants showed that they mimicked early NC phenotypes observed in fscn1a null mutants; however, these embryos also displayed NC migration and derivative phenotypes not observed in null mutants, including accumulation of p53-independent cell death. These data demonstrate that morpholinos can cause seemingly specific NC migration and derivative phenotypes, and thus have likely contributed to the inconsistencies surrounding NC gene function between species. We suggest that comparison of genetic mutants between different species is the most rigorous method for identifying conserved genetic mechanisms controlling NC development and is critical to identify new treatments for NC

  5. Mindfulness Meditation-Based Pain Relief Employs Different Neural Mechanisms Than Placebo and Sham Mindfulness Meditation-Induced Analgesia

    Science.gov (United States)

    Emerson, Nichole M.; Farris, Suzan R.; Ray, Jenna N.; Jung, Youngkyoo; McHaffie, John G.; Coghill, Robert C.

    2015-01-01

    Mindfulness meditation reduces pain in experimental and clinical settings. However, it remains unknown whether mindfulness meditation engages pain-relieving mechanisms other than those associated with the placebo effect (e.g., conditioning, psychosocial context, beliefs). To determine whether the analgesic mechanisms of mindfulness meditation are different from placebo, we randomly assigned 75 healthy, human volunteers to 4 d of the following: (1) mindfulness meditation, (2) placebo conditioning, (3) sham mindfulness meditation, or (4) book-listening control intervention. We assessed intervention efficacy using psychophysical evaluation of experimental pain and functional neuroimaging. Importantly, all cognitive manipulations (i.e., mindfulness meditation, placebo conditioning, sham mindfulness meditation) significantly attenuated pain intensity and unpleasantness ratings when compared to rest and the control condition (p meditation reduced pain intensity (p = 0.032) and pain unpleasantness (p meditation also reduced pain intensity (p = 0.030) and pain unpleasantness (p = 0.043) ratings more than sham mindfulness meditation. Mindfulness-meditation-related pain relief was associated with greater activation in brain regions associated with the cognitive modulation of pain, including the orbitofrontal, subgenual anterior cingulate, and anterior insular cortex. In contrast, placebo analgesia was associated with activation of the dorsolateral prefrontal cortex and deactivation of sensory processing regions (secondary somatosensory cortex). Sham mindfulness meditation-induced analgesia was not correlated with significant neural activity, but rather by greater reductions in respiration rate. This study is the first to demonstrate that mindfulness-related pain relief is mechanistically distinct from placebo analgesia. The elucidation of this distinction confirms the existence of multiple, cognitively driven, supraspinal mechanisms for pain modulation. SIGNIFICANCE

  6. The transcription factor neural retina leucine zipper (NRL) controls photoreceptor-specific expression of myocyte enhancer factor Mef2c from an alternative promoter.

    Science.gov (United States)

    Hao, Hong; Tummala, Padmaja; Guzman, Eduardo; Mali, Raghuveer S; Gregorski, Janina; Swaroop, Anand; Mitton, Kenneth P

    2011-10-07

    Neural retina leucine zipper (NRL) is an essential transcription factor for cell fate specification and functional maintenance of rod photoreceptors in the mammalian retina. In the Nrl(-/-) mouse retina, photoreceptor precursors fail to produce rods and generate functional cone photoreceptors that predominantly express S-opsin. Previous global expression analysis using microarrays revealed dramatically reduced expression of myocyte enhancer factor Mef2c in the adult Nrl(-/-) retina. We undertook this study to examine the biological relevance of Mef2c expression in retinal rod photoreceptors. Bioinformatics analysis, rapid analysis of cDNA ends (5'-RACE), and reverse transcription coupled with qPCR using splice site-specific oligonucleotides suggested that Mef2c is expressed in the mature retina from an alternative promoter. Chromatin immunoprecipitation (ChIP) studies showed the association of active RNA polymerase II and acetylated histone H3 just upstream of Mef2c exon 4, providing additional evidence for the utilization of an alternative promoter in the retina. In concordance, we observed the binding of NRL to a putative NRL-response element (NRE) at this location by ChIP-seq and electrophoretic mobility shift assays. NRL also activated the Mef2c alternative promoter in vitro and in vivo. Notably, MEF2C could support Rhodopsin promoter activity in rod photoreceptors. We conclude that Mef2c expression from an alternative promoter in the retina is regulated by NRL. Our studies also implicate MEF2C as a transcriptional regulator of homeostasis in rod photoreceptor cells.

  7. Growth Factors and Tension-Induced Skeletal Muscle Growth

    Science.gov (United States)

    Vandenburgh, Herman H.

    1994-01-01

    The project investigated biochemical mechanisms to enhance skeletal muscle growth, and developed a computer based mechanical cell stimulator system. The biochemicals investigated in this study were insulin/(Insulin like Growth Factor) IGF-1 and Steroids. In order to analyze which growth factors are essential for stretch-induced muscle growth in vitro, we developed a defined, serum-free medium in which the differentiated, cultured avian muscle fibers could be maintained for extended periods of time. The defined medium (muscle maintenance medium, MM medium) maintains the nitrogen balance of the myofibers for 3 to 7 days, based on myofiber diameter measurements and myosin heavy chain content. Insulin and IGF-1, but not IGF-2, induced pronounced myofiber hypertrophy when added to this medium. In 5 to 7 days, muscle fiber diameters increase by 71 % to 98% compared to untreated controls. Mechanical stimulation of the avian muscle fibers in MM medium increased the sensitivity of the cells to insulin and IGF-1, based on a leftward shift of the insulin dose/response curve for protein synthesis rates. (54). We developed a ligand binding assay for IGF-1 binding proteins and found that the avian skeletal muscle cultures produced three major species of 31, 36 and 43 kD molecular weight (54) Stretch of the myofibers was found to have no significant effect on the efflux of IGF-1 binding proteins, but addition of exogenous collagen stimulated IGF-1 binding protein production 1.5 to 5 fold. Steroid hormones have a profound effect on muscle protein turnover rates in vivo, with the stress-related glucocorticoids inducing rapid skeletal muscle atrophy while androgenic steroids induce skeletal muscle growth. Exercise in humans and animals reduces the catabolic effects of glucocorticoids and may enhance the anabolic effects of androgenic steroids on skeletal muscle. In our continuing work on the involvement of exogenrus growth factors in stretch-induced avian skeletal muscle growth, we

  8. Growth factor deprivation induces cytosolic translocation of SIRT1

    Science.gov (United States)

    Meng, Chengbo; Xing, Da; Wu, Shengnan; Huang, Lei

    2010-02-01

    Sirtuin type 1 (SIRT1), a NAD+-dependent histone deacetylases, plays a critical role in cellular senescence, aging and longevity. In general, SIRT1 is localized in nucleus and is believed as a nuclear protein. Though overexpression of SIRT1 delays senescence, SIRT1-protein levels decline naturally in thymus and heart during aging. In the present studies, we investigated the subcellular localization of SIRT1 in response to growth factor deprivation in African green monkey SV40-transformed kidney fibroblast cells (COS-7). Using SIRT1-EGFP fluorescence reporter, we found that SIRT1 localized to nucleus in physiological conditions. We devised a model enabling cell senescence via growth factor deprivation, and we found that SIRT1 partially translocated to cytosol under the treatment, suggesting a reduced level of SIRT1's activity. We found PI3K/Akt pathway was involved in the inhibition of SIRT1's cytosolic translocation, because inhibition of these kinases significantly decreased the amount of SIRT1 maintained in nucleus. Taken together, we demonstrated that growth factor deprivation induces cytosolic translocation of SIRT1, which suggesting a possible connection between cytoplasm-localized SIRT1 and the aging process.

  9. Folate deficiency-induced oxidative stress contributes to neuropathy in young and aged zebrafish--implication in neural tube defects and Alzheimer's diseases.

    Science.gov (United States)

    Kao, Tseng-Ting; Chu, Chia-Yi; Lee, Gang-Hui; Hsiao, Tsun-Hsien; Cheng, Nai-Wei; Chang, Nan-Shan; Chen, Bing-Hung; Fu, Tzu-Fun

    2014-11-01

    Folate is a nutrient essential for the development, function and regeneration of nervous systems. Folate deficiency has been linked to many neurological disorders including neural tube defects in fetus and Alzheimer's diseases in the elderly. However, the etiology underlying these folate deficiency-associated diseases is not completely understood. In this study, zebrafish transgenic lines with timing and duration-controllable folate deficiency were developed by ectopically overexpressing a recombinant EGFP-γ-glutamyl hydrolase (γGH). Impeded neural crest cell migration was observed in the transgenic embryos when folate deficiency was induced in early stages, leading to defective neural tube closure and hematopoiesis. Adding reduced folate or N-acetylcysteine reversed the phenotypic anomalies, supporting the causal link between the increased oxidative stress and the folate deficiency-induced abnormalities. When folate deficiency was induced in aged fish accumulation of beta-amyloid and phosphorylated Tau protein were found in the fish brain cryo-sections. Increased autophagy and accumulation of acidic autolysosome were apparent in folate deficient neuroblastoma cells, which were reversed by reduced folate or N-acetylcysteine supplementation. Decreased expression of cathepsin B, a lysosomal protease, was also observed in cells and tissue with folate deficiency. We concluded that folate deficiency-induced oxidative stress contributed to the folate deficiency-associated neuropathogenesis in both early and late stages of life.

  10. Initiation to end point: the multiple roles of fibroblast growth factors in neural development.

    Science.gov (United States)

    Mason, Ivor

    2007-08-01

    From a wealth of experimental findings, derived from both in vitro and in vivo experiments, it is becoming clear that fibroblast growth factors regulate processes that are central to all aspects of nervous system development. Some of these functions are well known, whereas others, such as the roles of these proteins in axon guidance and synaptogenesis, have been established only recently. The emergent picture is one of remarkable economy, in which this family of ligands is deployed and redeployed at successive developmental stages to sculpt the nervous system.

  11. A multifactorial analysis of obesity as CVD risk factor: Use of neural network based methods in a nutrigenetics context

    Directory of Open Access Journals (Sweden)

    Valavanis Ioannis K

    2010-09-01

    Full Text Available Abstract Background Obesity is a multifactorial trait, which comprises an independent risk factor for cardiovascular disease (CVD. The aim of the current work is to study the complex etiology beneath obesity and identify genetic variations and/or factors related to nutrition that contribute to its variability. To this end, a set of more than 2300 white subjects who participated in a nutrigenetics study was used. For each subject a total of 63 factors describing genetic variants related to CVD (24 in total, gender, and nutrition (38 in total, e.g. average daily intake in calories and cholesterol, were measured. Each subject was categorized according to body mass index (BMI as normal (BMI ≤ 25 or overweight (BMI > 25. Two artificial neural network (ANN based methods were designed and used towards the analysis of the available data. These corresponded to i a multi-layer feed-forward ANN combined with a parameter decreasing method (PDM-ANN, and ii a multi-layer feed-forward ANN trained by a hybrid method (GA-ANN which combines genetic algorithms and the popular back-propagation training algorithm. Results PDM-ANN and GA-ANN were comparatively assessed in terms of their ability to identify the most important factors among the initial 63 variables describing genetic variations, nutrition and gender, able to classify a subject into one of the BMI related classes: normal and overweight. The methods were designed and evaluated using appropriate training and testing sets provided by 3-fold Cross Validation (3-CV resampling. Classification accuracy, sensitivity, specificity and area under receiver operating characteristics curve were utilized to evaluate the resulted predictive ANN models. The most parsimonious set of factors was obtained by the GA-ANN method and included gender, six genetic variations and 18 nutrition-related variables. The corresponding predictive model was characterized by a mean accuracy equal of 61.46% in the 3-CV testing sets

  12. Dauricine inhibits insulin-like growth factor-Ⅰ-induced hypoxia inducible factor 1α protein accumulation and vascular endothelial growth factor expression in human breast cancer cells

    Institute of Scientific and Technical Information of China (English)

    Xu-dong TANG; Xin ZHOU; Ke-yuan ZHOU

    2009-01-01

    Aim: To investigate the effects of dauricine (Dau) on insulin-like growth factor-Ⅰ (IGF-Ⅰ)-induced hypoxia inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression in human breast cancer cells (MCF-7).Methods: Serum-starved MCF-7 cells were pretreated for 1 h with different concentrations of Dau, followed by incubation with IGF-Ⅰ for 6 h. HIF-1α and VEGF protein expression levels were analyzed by Western blotting and ELISA, respectively.HIF-1α and VEGF mRNA levels were determined by real-time PCR. In vitro angiogenesis was observed via the human umbilical vein endothelial cell (HUVEC) tube formation assay. An in vitro invasion assay on HUVECs was performed.Results: Dau significantly inhibited IGF-Ⅰ-induced HIF-1α protein expression but had no effect on HIF-1α mRNA expression. However, Dau remarkably suppressed VEGF expression at both protein and mRNA levels in response to IGF-Ⅰ.Mechanistically, Dau suppressed IGF-Ⅰ-induced HIF-1α and VEGF protein expression mainly by blocking the activation of PI-3K/AKT/mTOR signaling pathway. In addition, Dan reduced IGF-Ⅰ-induced HIF-1α protein accumulation by inhibiting its synthesis as well as by promoting its degradation. Functionally, Dau inhibited angiogenesis in vitro. Moreover, Dau had a direct effect on IGF-Ⅰ-induced invasion of HUVECs.Conclusion: Dau inhibits human breast cancer angiogenesis by suppressing HIF-1α protein accumulation and VEGF expression, which may provide a novel potential mechanism for the anticancer activities of Dau in human breast cancer.

  13. Cavitation Induced Structural and Neural Damage in Live Brain Tissue Slices: Relevance to TBI

    Science.gov (United States)

    2014-09-29

    the value of this experimental platform to investigate the single bubble cavitation- induced damage in a biological tissue is illustrated with an...Lei Wu, Malisa Sarntinoranont, Huikai Xie1. Refractive index measurement of acute rat brain tissue slices using optical coherence tomography, Optics...b-TBI, i.e. what is “broken”, in the brain during exposure to shock loading is currently unknown. While blast waves are well known to have negative

  14. Factors inducing human umbilical cord blood-derived mesenchymal stem cells to differentiate into neuron-like cells

    Institute of Scientific and Technical Information of China (English)

    Nawei Zhang; Fengqing Ji

    2006-01-01

    OBJECTIVE:Human umbilical cord blood-derived mesenchymal stem cells (HUCB-derived MSCs)can differentiate into neuron-like cells,which can be used to treat some central nervous system(CNS)diseases.To investigate the factors,which can induce HUCB-derived MSCs to differentiate into neuron-like cells,so as to find effective methods for future clinical application.DATA SOURCES:Using the key terms"human umbilical cord blood"combined with"mesenchymal stem cells,neuron-like cells,neural cells"respectively,the relevant articles in English published during the period from January 1999 to June 2006 were searched from the Medline database.Meanwhile,relevant Chinese articles published from January 1999 to June 2006 were searched Using the same key terms.STUDY SELECTION: All articles associated with the differentiation from human umbilical cord blood into neuron-like cells were selected firstly.Then the full texts were looked up by searchling Ovid medical Journals full-text database and Elsevier Electrical Journals Full-text Database.Articles with full expeiments,enrolled in inducible factors or involved inducible mechanism were retdeved.DATA EXTRACTION:Among 119 collected correlative articles,29 were involved and 90 were excluded.DATA SYNTHESIS:The inducible factors of HUCB-derived MSCs differentiatling into neuron-like cells included renal endothelial growth factors,fibroblasts,β-mercaptoethanol,dimethyl sulfoxide,butyl hydroxyl anisol,brain-derived neurotrophic factor,Danshen,retinoic acid,sodium ferulate and so on,but its mechanism was unclear.CONCLUSION:Human umbilical cord blood-derived MSCs can differentiate into neuron-like cells,with varied inductors.

  15. Pentylenetetrazol-induced seizure-like behavior and neural hyperactivity in the medicinal leech.

    Science.gov (United States)

    Hahn, Elizabeth; Burrell, Brian

    2015-01-01

    This study examined the capacity of a known pro-epileptic drug, pentylenetetrazol (PTZ), to elicit seizure-like activity in the medicinal leech, Hirudo verbana. During in vivo experiments, PTZ elicited increased motor activity in a concentration-dependent manner with the highest concentration (10 mM) eliciting episodes of highly uncoordinated exploratory and swimming behavior. Co-application of the anti-epileptic drug, phenytoin, failed to reduce the absolute amount of PTZ-induced motor behavior, but was able to prevent expression of abnormal exploratory and swimming behaviors. During in vitro experiments in which extracellular recordings of connective nerve activity were made, bath application of 1 μM PTZ in Mg(2+)-free saline elicited a significant increase in spontaneous activity. This PTZ-induced increase in activity was completely inhibited by phenytoin. Interestingly, PTZ-induced hyperactivity was also blocked by co-application of the endocannabinoid 2-arachidonoyl glycerol and the selective serotonin re-uptake inhibitor (SSRI) fluoxetine. These findings suggest that the leech can be a useful system in which to study potential anti-epileptic treatments.

  16. Cognitive disorder and changes in cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury

    Institute of Scientific and Technical Information of China (English)

    Weiliang Zhao; Dezhi Kang; Yuanxiang Lin

    2008-01-01

    BACKGROUND: Learning and memory damage is one of the most permanent and the severest symptoms of traumatic brain injury; it can seriously influence the normal life and work of patients. Some research has demonstrated that cognitive disorder is closely related to nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor. OBJECTIVE: To summarize the cognitive disorder and changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury. RETRIEVAL STRATEGY: A computer-based online search was conducted in PUBMED for English language publications containing the key words "brain injured, cognitive handicap, acetylcholine, N-methyl-D aspartate receptors, neural cell adhesion molecule, brain-derived neurotrophic factor" from January 2000 to December 2007. There were 44 papers in total. Inclusion criteria: ① articles about changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury; ② articles in the same researching circle published in authoritative journals or recently published. Exclusion criteria: duplicated articles.LITERATURE EVALUATION: References were mainly derived from research on changes in these four factors following brain injury. The 20 included papers were clinical or basic experimental studies. DATA SYNTHESIS: After craniocerebral injury, changes in these four factors in brain were similar to those during recovery from cognitive disorder, to a certain degree. Some data have indicated that activation of nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor could greatly improve cognitive disorder following brain injury. However, there are still a lot of questions remaining; for example, how do these

  17. Low-Dose Methylmercury-Induced Genes Regulate Mitochondrial Biogenesis via miR-25 in Immortalized Human Embryonic Neural Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Xinjin Wang

    2016-12-01

    Full Text Available Mitochondria are essential organelles and important targets for environmental pollutants. The detection of mitochondrial biogenesis and generation of reactive oxygen species (ROS and p53 levels following low-dose methylmercury (MeHg exposure could expand our understanding of underlying mechanisms. Here, the sensitivity of immortalized human neural progenitor cells (ihNPCs upon exposure to MeHg was investigated. We found that MeHg altered cell viability and the number of 5-ethynyl-2′-deoxyuridine (EdU-positive cells. We also observed that low-dose MeHg exposure increased the mRNA expression of cell cycle regulators. We observed that MeHg induced ROS production in a dose-dependent manner. In addition, mRNA levels of peroxisome-proliferator-activated receptor gammacoactivator-1α (PGC-1α, mitochondrial transcription factor A (TFAM and p53-controlled ribonucleotide reductase (p53R2 were significantly elevated, which were correlated with the increase of mitochondrial DNA (mtDNA copy number at a concentration as low as 10 nM. Moreover, we examined the expression of microRNAs (miRNAs known as regulatory miRNAs of p53 (i.e., miR-30d, miR-1285, miR-25. We found that the expression of these miRNAs was significantly downregulated upon MeHg treatment. Furthermore, the overexpression of miR-25 resulted in significantly reducted p53 protein levels and decreased mRNA expression of genes involved in mitochondrial biogenesis regulation. Taken together, these results demonstrated that MeHg could induce developmental neurotoxicity in ihNPCs through altering mitochondrial functions and the expression of miRNA.

  18. Stochastic simulation of notch signaling reveals novel factors that mediate the differentiation of neural stem cells.

    Science.gov (United States)

    Tzou, Wen-Shyong; Lo, Ying-Tsang; Pai, Tun-Wen; Hu, Chin-Hwa; Li, Chung-Hao

    2014-07-01

    Notch signaling controls cell fate decisions and regulates multiple biological processes, such as cell proliferation, differentiation, and apoptosis. Computational modeling of the deterministic simulation of Notch signaling has provided important insight into the possible molecular mechanisms that underlie the switch from the undifferentiated stem cell to the differentiated cell. Here, we constructed a stochastic model of a Notch signaling model containing Hes1, Notch1, RBP-Jk, Mash1, Hes6, and Delta. mRNA and protein were represented as a discrete state, and 334 reactions were employed for each biochemical reaction using a graphics processing unit-accelerated Gillespie scheme. We employed the tuning of 40 molecular mechanisms and revealed several potential mediators capable of enabling the switch from cell stemness to differentiation. These effective mediators encompass different aspects of cellular regulations, including the nuclear transport of Hes1, the degradation of mRNA (Hes1 and Notch1) and protein (Notch1), the association between RBP-Jk and Notch intracellular domain (NICD), and the cleavage efficiency of the NICD. These mechanisms overlap with many modifiers that have only recently been discovered to modulate the Notch signaling output, including microRNA action, ubiquitin-mediated proteolysis, and the competitive binding of the RBP-Jk-DNA complex. Moreover, we identified the degradation of Hes1 mRNA and nuclear transport of Hes1 as the dominant mechanisms that were capable of abolishing the cell state transition induced by other molecular mechanisms.

  19. Effect of controlled release of brain-derived neurotrophic factor and neurotrophin-3 from collagen gel on neural stem cells.

    Science.gov (United States)

    Huang, Fei; Wu, Yunfeng; Wang, Hao; Chang, Jun; Ma, Guangwen; Yin, Zongsheng

    2016-01-20

    This study aimed to examine the effect of controlled release of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) from collagen gel on rat neural stem cells (NSCs). With three groups of collagen gel, BDNF/collagen gel, and NT-3/collagen gel as controls, BDNF and NT-3 were tested in the BDNF-NT-3/collagen gel group at different time points. The enzyme-linked immunosorbent assay results showed that BDNF and NT-3 were steadily released from collagen gels for 10 days. The cell viability test and the bromodeoxyuridine incorporation assay showed that BDNF-NT-3/collagen gel supported the survival and proliferation of NSCs. The results also showed that the length of processes was markedly longer and differentiation percentage from NSCs into neurons was much higher in the BDNF-NT-3/collagen gel group than those in the collagen gel, BDNF/collagen gel, and NT-3/collagen gel groups. These findings suggest that BDNF-NT-3/collagen gel could significantly improve the ability of NSCs proliferation and differentiation.

  20. Tumour necrosis factor-alpha impairs neuronal differentiation but not proliferation of hippocampal neural precursor cells: Role of Hes1.

    Science.gov (United States)

    Keohane, Aoife; Ryan, Sinead; Maloney, Eimer; Sullivan, Aideen M; Nolan, Yvonne M

    2010-01-01

    Tumour necrosis factor-alpha (TNFalpha) is a pro-inflammatory cytokine, which influences neuronal survival and function yet there is limited information available on its effects on hippocampal neural precursor cells (NPCs). We show that TNFalpha treatment during proliferation had no effect on the percentage of proliferating cells prepared from embryonic rat hippocampal neurosphere cultures, nor did it affect cell fate towards either an astrocytic or neuronal lineage when cells were then allowed to differentiate. However, when cells were differentiated in the presence of TNFalpha, significantly reduced percentages of newly born and post-mitotic neurons, significantly increased percentages of astrocytes and increased expression of TNFalpha receptors, TNF-R1 and TNF-R2, as well as expression of the anti-neurogenic Hes1 gene, were observed. These data indicate that exposure of hippocampal NPCs to TNFalpha when they are undergoing differentiation but not proliferation has a detrimental effect on their neuronal lineage fate, which may be mediated through increased expression of Hes1.

  1. Factors that mitigate war-induced anxiety and mental distress.

    Science.gov (United States)

    Almedom, Astier M

    2004-07-01

    The effects of war-induced anxiety and mental distress on individuals and groups can either be mitigated or exacerbated by 'humanitarian action'. This paper focuses on two key factors that protect the mental well-being of war-affected populations: organized displacement or assisted relocation; and coordinated humanitarian aid operations that are responsive to local needs. Qualitative data from two internally displaced person (IDP) camps in Eritrea are presented. Analysis of these data serves to substantiate and refine a working hypothesis: that social support of the right type, provided at the right time and level, can mitigate the worst effects of war and displacement on victims/survivors. An integrated model of psychosocial transition is suggested. The implications of this approach for humanitarian policy and practice are discussed in the wider context of current debates and lamentations of the 'humanitarian idea'.

  2. Depolarization Induced Suppression of Excitation and the Emergence of Ultraslow Rhythms in Neural Networks

    Science.gov (United States)

    Hlinka, J.; Coombes, S.

    2010-02-01

    Ultraslow fluctuations (0.01-0.1 Hz) are a feature of intrinsic brain activity of as yet unclear origin. We propose a candidate mechanism based on retrograde endocannabinoid signaling in a synaptically coupled network of excitatory neurons. This is known to cause depolarization-induced suppression of excitation (DISE), which we model phenomenologically. We construct emergent network oscillations in a globally coupled network and show that for strong synaptic coupling DISE can lead to a synchronized population burst at the frequencies of resting brain rhythms.

  3. Epidermal growth factor signaling induces behavioral quiescence in Caenorhabditis elegans.

    Science.gov (United States)

    Van Buskirk, Cheryl; Sternberg, Paul W

    2007-10-01

    The epidermal growth factor receptor (EGFR)/ErbB receptor tyrosine kinases regulate several aspects of development, including the development of the mammalian nervous system. ErbB signaling also has physiological effects on neuronal function, with influences on synaptic plasticity and daily cycles of activity. However, little is known about the effectors of EGFR activation in neurons. Here we show that EGF signaling has a nondevelopmental effect on behavior in Caenorhabditis elegans. Ectopic expression of the EGF-like ligand LIN-3 at any stage induces a reversible cessation of feeding and locomotion. These effects are mediated by