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Sample records for human dorsal root

  1. RNA-Seq Analysis of Human Trigeminal and Dorsal Root Ganglia with a Focus on Chemoreceptors.

    Directory of Open Access Journals (Sweden)

    Caroline Flegel

    Full Text Available The chemosensory capacity of the somatosensory system relies on the appropriate expression of chemoreceptors, which detect chemical stimuli and transduce sensory information into cellular signals. Knowledge of the complete repertoire of the chemoreceptors expressed in human sensory ganglia is lacking. This study employed the next-generation sequencing technique (RNA-Seq to conduct the first expression analysis of human trigeminal ganglia (TG and dorsal root ganglia (DRG. We analyzed the data with a focus on G-protein coupled receptors (GPCRs and ion channels, which are (potentially involved in chemosensation by somatosensory neurons in the human TG and DRG. For years, transient receptor potential (TRP channels have been considered the main group of receptors for chemosensation in the trigeminal system. Interestingly, we could show that sensory ganglia also express a panel of different olfactory receptors (ORs with putative chemosensory function. To characterize OR expression in more detail, we performed microarray, semi-quantitative RT-PCR experiments, and immunohistochemical staining. Additionally, we analyzed the expression data to identify further known or putative classes of chemoreceptors in the human TG and DRG. Our results give an overview of the major classes of chemoreceptors expressed in the human TG and DRG and provide the basis for a broader understanding of the reception of chemical cues.

  2. Human Embryonic Stem Cell-Derived Progenitors Assist Functional Sensory Axon Regeneration after Dorsal Root Avulsion Injury

    OpenAIRE

    Hoeber, Jan; Trolle, Carl; König, Niclas; Du, Zhongwei; Gallo, Alessandro; Hermans, Emmanuel; Aldskogius, Håkan; Shortland, Peter; Zhang, Su-Chun; Deumens, Ronald; Kozlova, Elena N

    2015-01-01

    Dorsal root avulsion results in permanent impairment of sensory functions due to disconnection between the peripheral and central nervous system. Improved strategies are therefore needed to reconnect injured sensory neurons with their spinal cord targets in order to achieve functional repair after brachial and lumbosacral plexus avulsion injuries. Here, we show that sensory functions can be restored in the adult mouse if avulsed sensory fibers are bridged with the spinal cord by human neural ...

  3. Effect of Human Genetic Variability on Gene Expression in Dorsal Root Ganglia and Association with Pain Phenotypes

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    Marc Parisien

    2017-05-01

    Full Text Available Dorsal root ganglia (DRG relay sensory information to the brain, giving rise to the perception of pain, disorders of which are prevalent and burdensome. Here, we mapped expression quantitative trait loci (eQTLs in a collection of human DRGs. DRG eQTLs were enriched within untranslated regions of coding genes of low abundance, with some overlapping with other brain regions and blood cell cis-eQTLs. We confirm functionality of identified eQTLs through their significant enrichment within open chromatin and highly deleterious SNPs, particularly at the exon level, suggesting substantial contribution of eQTLs to alternative splicing regulation. We illustrate pain-related genetic association results explained by DRG eQTLs, with the strongest evidence for contribution of the human leukocyte antigen (HLA locus, confirmed using a mouse inflammatory pain model. Finally, we show that DRG eQTLs are found among hits in numerous genome-wide association studies, suggesting that this dataset will help address pain components of non-pain disorders.

  4. Atopic keratinocytes induce increased neurite outgrowth in a coculture model of porcine dorsal root ganglia neurons and human skin cells.

    Science.gov (United States)

    Roggenkamp, Dennis; Falkner, Susanne; Stäb, Franz; Petersen, Marlen; Schmelz, Martin; Neufang, Gitta

    2012-07-01

    Skin of patients suffering from atopic eczema displays a higher epidermal nerve fiber density, associated with neurogenic inflammation and pruritus. Using an in vitro coculture system, allowing a spatially compartmented culture of somata from porcine dorsal root ganglion neurons and human primary skin cells, we investigated the influence of dermal fibroblasts and keratinocytes on neurite outgrowth. In comparison with dermal fibroblasts, keratinocytes induced more branched and less calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers. By adding neutralizing antibodies, we showed that nerve growth factor (NGF) and glial cell-line-derived neurotrophic factor (GDNF) are pivotal neurotrophic factors of skin cell-induced neurite outgrowth. Keratinocytes and dermal fibroblasts secreted different ratios of neurotrophic factors, influencing morphology and CGRP immunoreactivity of neurites. To investigate changes of the peripheral nervous system in the pathogenesis of atopic eczema in vitro, we analyzed neurite outgrowth mediated by atopic skin cells. Atopic keratinocytes produced elevated levels of NGF and mediated an increased outgrowth of CGRP-positive sensory fibers. Our results demonstrate the impact of dermal fibroblasts and keratinocytes on skin innervation and emphasize the role of keratinocytes as key players of hyperinnervation in atopic eczema.

  5. α-Conotoxin Vc1.1 inhibits human dorsal root ganglion neuroexcitability and mouse colonic nociception via GABAB receptors.

    Science.gov (United States)

    Castro, Joel; Harrington, Andrea M; Garcia-Caraballo, Sonia; Maddern, Jessica; Grundy, Luke; Zhang, Jingming; Page, Guy; Miller, Paul E; Craik, David J; Adams, David J; Brierley, Stuart M

    2017-06-01

    α-Conotoxin Vc1.1 is a small disulfide-bonded peptide from the venom of the marine cone snail Conus victoriae. Vc1.1 has antinociceptive actions in animal models of neuropathic pain, but its applicability to inhibiting human dorsal root ganglion (DRG) neuroexcitability and reducing chronic visceral pain (CVP) is unknown. We determined the inhibitory actions of Vc1.1 on human DRG neurons and on mouse colonic sensory afferents in healthy and chronic visceral hypersensitivity (CVH) states. In mice, visceral nociception was assessed by neuronal activation within the spinal cord in response to noxious colorectal distension (CRD). Quantitative-reverse-transcription-PCR, single-cell-reverse-transcription-PCR and immunohistochemistry determined γ-aminobutyric acid receptor B (GABABR) and voltage-gated calcium channel (CaV2.2, CaV2.3) expression in human and mouse DRG neurons. Vc1.1 reduced the excitability of human DRG neurons, whereas a synthetic Vc1.1 analogue that is inactive at GABABR did not. Human DRG neurons expressed GABABR and its downstream effector channels CaV2.2 and CaV2.3. Mouse colonic DRG neurons exhibited high GABABR, CaV2.2 and CaV2.3 expression, with upregulation of the CaV2.2 exon-37a variant during CVH. Vc1.1 inhibited mouse colonic afferents ex vivo and nociceptive signalling of noxious CRD into the spinal cord in vivo, with greatest efficacy observed during CVH. A selective GABABR antagonist prevented Vc1.1-induced inhibition, whereas blocking both CaV2.2 and CaV2.3 caused inhibition comparable with Vc1.1 alone. Vc1.1-mediated activation of GABABR is a novel mechanism for reducing the excitability of human DRG neurons. Vc1.1-induced activation of GABABR on the peripheral endings of colonic afferents reduces nociceptive signalling. The enhanced antinociceptive actions of Vc1.1 during CVH suggest it is a novel candidate for the treatment for CVP. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a

  6. Minimally invasive convection-enhanced delivery of biologics into dorsal root ganglia: validation in the pig model and prospective modeling in humans. Technical note.

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    Pleticha, Josef; Maus, Timothy P; Christner, Jodie A; Marsh, Michael P; Lee, Kendall H; Hooten, W Michael; Beutler, Andreas S

    2014-10-01

    Dorsal root ganglia (DRG) are critical anatomical structures involved in nociception. Intraganglionic (IG) drug delivery is therefore an important route of administration for novel analgesic therapies. Although IG injection in large animal models is highly desirable for preclinical biodistribution and toxicology studies of new drugs, no method to deliver pharmaceutical agents into the DRG has been reported in any large species. The present study describes a minimally invasive technique of IG agent delivery in domestic swine, one of the most common large animal models. The technique utilizes CT guidance for DRG targeting and a custom-made injection assembly for convection enhanced delivery (CED) of therapeutic agents directly into DRG parenchyma. The DRG were initially visualized by CT myelography to determine the optimal access route to the DRG. The subsequent IG injection consisted of 3 steps. First, a commercially available guide needle was advanced to a position dorsolateral to the DRG, and the dural root sleeve was punctured, leaving the guide needle contiguous with, but not penetrating, the DRG. Second, the custom-made stepped stylet was inserted through the guide needle into the DRG parenchyma. Third, the stepped stylet was replaced by the custom-made stepped needle, which was used for the IG CED. Initial dye injections performed in pig cadavers confirmed the accuracy of DRG targeting under CT guidance. Intraganglionic administration of adeno-associated virus in vivo resulted in a unilateral transduction of the injected DRG, with 33.5% DRG neurons transduced. Transgene expression was also found in the dorsal root entry zones at the corresponding spinal levels. The results thereby confirm the efficacy of CED by the stepped needle and a selectivity of DRG targeting. Imaging-based modeling of the procedure in humans suggests that IG CED may be translatable to the clinical setting.

  7. Adeno-associated virus and lentivirus vectors mediate efficient and sustained transduction of cultured mouse and human dorsal root ganglia sensory neurons.

    Science.gov (United States)

    Fleming, J; Ginn, S L; Weinberger, R P; Trahair, T N; Smythe, J A; Alexander, I E

    2001-01-01

    Peripheral nervous system (PNS) sensory neurons are directly involved in the pathophysiology of numerous inherited and acquired neurological conditions. Therefore, efficient and stable gene delivery to these postmitotic cells has significant therapeutic potential. Among contemporary vector systems capable of neuronal transduction, only those based on herpes simplex virus have been extensively evaluated in PNS neurons. We therefore investigated the transduction performance of recombinant adeno-associated virus type 2 (AAV) and VSV-G-pseudotyped lentivirus vectors derived from human immunodeficiency virus (HIV-1) in newborn mouse and fetal human dorsal root ganglia (DRG) sensory neurons. In dissociated mouse DRG cultures both vectors achieved efficient transduction of sensory neurons at low multiplicities of infection (MOIs) and sustained transgene expression within a 28-day culture period. Interestingly, the lentivirus vector selectively transduced neurons in murine cultures, in contrast to human cultures, in which Schwann and fibroblast-like cells were also transduced. Recombinant AAV transduced all three cell types in both mouse and human cultures. After direct microinjection of murine DRG explants, maximal transduction efficiencies of 20 and 200 transducing units per neuronal transductant were achieved with AAV and lentivirus vectors, respectively. Most importantly, both vectors achieved efficient and sustained transduction of human sensory neurons in dissociated cultures, thereby directly demonstrating the exciting potential of these vectors for gene therapy applications in the PNS.

  8. Neuronal Subtype and Satellite Cell Tropism Are Determinants of Varicella-Zoster Virus Virulence in Human Dorsal Root Ganglia Xenografts In Vivo.

    Directory of Open Access Journals (Sweden)

    Leigh Zerboni

    2015-06-01

    Full Text Available Varicella zoster virus (VZV, a human alphaherpesvirus, causes varicella during primary infection. VZV reactivation from neuronal latency may cause herpes zoster, post herpetic neuralgia (PHN and other neurologic syndromes. To investigate VZV neuropathogenesis, we developed a model using human dorsal root ganglia (DRG xenografts in immunodeficient (SCID mice. The SCID DRG model provides an opportunity to examine characteristics of VZV infection that occur in the context of the specialized architecture of DRG, in which nerve cell bodies are ensheathed by satellite glial cells (SGC which support neuronal homeostasis. We hypothesized that VZV exhibits neuron-subtype specific tropism and that VZV tropism for SGC contributes to VZV-related ganglionopathy. Based on quantitative analyses of viral and cell protein expression in DRG tissue sections, we demonstrated that, whereas DRG neurons had an immature neuronal phenotype prior to implantation, subtype heterogeneity was observed within 20 weeks and SGC retained the capacity to maintain neuronal homeostasis longterm. Profiling VZV protein expression in DRG neurons showed that VZV enters peripherin+ nociceptive and RT97+ mechanoreceptive neurons by both axonal transport and contiguous spread from SGC, but replication in RT97+ neurons is blocked. Restriction occurs even when the SGC surrounding the neuronal cell body were infected and after entry and ORF61 expression, but before IE62 or IE63 protein expression. Notably, although contiguous VZV spread with loss of SGC support would be predicted to affect survival of both nociceptive and mechanoreceptive neurons, RT97+ neurons showed selective loss relative to peripherin+ neurons at later times in DRG infection. Profiling cell factors that were upregulated in VZV-infected DRG indicated that VZV infection induced marked pro-inflammatory responses, as well as proteins of the interferon pathway and neuroprotective responses. These neuropathologic changes

  9. Expression of interleukin-1 beta in rat dorsal root ganglia

    NARCIS (Netherlands)

    Copray, JCVM; Mantingh, [No Value; Brouwer, N; Biber, K; Kust, BM; Liem, RSB; Huitinga, [No Value; Tilders, FJH; Van Dam, AM; Boddeke, HWGM

    2001-01-01

    The expression of interleukin-lp was examined in dorsal root ganglion (DRG) neurons from adult rats using non-radioactive in Situ hybridization and immunocytochemistry. At all spinal levels, approximately 70% of the DRG neurons appeared to express IL-1 beta mRNA: about 80% of these DRG neurons

  10. Oscillatory interaction between dorsal root excitability and dorsal root potentials in the spinal cord of the turtle

    DEFF Research Database (Denmark)

    Delgado-Lezama, R; Perrier, J F; Hounsgaard, J

    1999-01-01

    The response to dorsal root stimulation, at one to two times threshold, was investigated in the isolated cervical enlargement of the turtle spinal cord. At frequencies near 10 Hz the synaptic response in motoneurons and the cord dorsum potential, after an initial lag time, oscillated in amplitude...

  11. Purification of Dorsal Root Ganglion Neurons from Rat by Immunopanning

    OpenAIRE

    Zuchero, J. Bradley

    2014-01-01

    Dorsal root ganglion neurons (DRGs) are sensory neurons that facilitate somatosensation and have been used to study neurite outgrowth, regeneration, and degeneration and PNS and CNS myelination. Studies of DRGs have relied on cell isolation strategies that generally involve extended culture in the presence of antimitotic agents or other cytotoxic treatments that target dividing cells. The surviving cells typically are dependent on serum for growth. Other methods, involving purification of DRG...

  12. The Molecular Fingerprint of Dorsal Root and Trigeminal Ganglion Neurons

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    Douglas M. Lopes

    2017-09-01

    Full Text Available The dorsal root ganglia (DRG and trigeminal ganglia (TG are clusters of cell bodies of highly specialized sensory neurons which are responsible for relaying information about our environment to the central nervous system. Despite previous efforts to characterize sensory neurons at the molecular level, it is still unknown whether those present in DRG and TG have distinct expression profiles and therefore a unique molecular fingerprint. To address this question, we isolated lumbar DRG and TG neurons using fluorescence-activated cell sorting from Advillin-GFP transgenic mice and performed RNA sequencing. Our transcriptome analyses showed that, despite being overwhelmingly similar, a number of genes are differentially expressed in DRG and TG neurons. Importantly, we identified 24 genes which were uniquely expressed in either ganglia, including an arginine vasopressin receptor and several homeobox genes, giving each population a distinct molecular fingerprint. We compared our findings with published studies to reveal that many genes previously reported to be present in neurons are in fact likely to originate from other cell types in the ganglia. Additionally, our neuron-specific results aligned well with a dataset examining whole human TG and DRG. We propose that the data can both improve our understanding of primary afferent biology and help contribute to the development of drug treatments and gene therapies which seek targets with unique or restricted expression patterns.

  13. Position of dorsal root ganglia in the lumbosacral region in patients with radiculopathy.

    Science.gov (United States)

    Moon, Hyun Seog; Kim, Yeon Dong; Song, Bang Hoon; Cha, Young Deog; Song, Jang Ho; Lee, Mi Hyeon

    2010-12-01

    When applying pulsed radiofrequency on dorsal root ganglia for treating chronic lower back pain, maximum efficiency can be expected when a needle is placed 1-2 cm peripheral to the dorsal root ganglion. The object of this study is to analyze images taken after adding contrast to transforaminal epidural injection, categorize root ganglia according to anatomical position, and provide a reference for efficient needle positioning in applying pulsed radiofrequency on dorsal root ganglia. From January 2008 to January 2009, 457 patients who visited our hospital for root pain or radiculopathy were treated with transforaminal epidural injection on the nerve roots based on the dermatome of the painful area. Anteroposterior views were taken after injection of contrast. A virtual line was made by connecting the internal and external parts of the spinal pedicle from the contrast images. Then the dorsal root ganglia were categorized as intraspinal (IS), intraforaminal (IF), or extraforaminal (EF). In the fourth lumbar spine, dorsal root ganglia positions were 48% IF, 41% IS, and 6% EF. In the fifth lumbar spine, dorsal root ganglia positions were 75% IF, 10% IS, and 6% EF. In the first sacral spine, dorsal root ganglia locations were 8% IF and 83% IS. Positional categorization of dorsal root ganglia according to contrast images was proven to be good anatomical references for effective radiofrequency or blocking of dorsal root ganglia.

  14. [Expression of Sema3A and NP-1 in spinal cord and spared dorsal root ganglion after partial dorsal root rhizotomy of cat].

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    Ding, Yan; Zhang, Wei; Huang, Qian; Peng, Jin; Zhao, Xiu-jun; Xu, Ai-li; Zhou, Xue

    2008-01-01

    To investigate the expression of semaphorin 3A (Sema3A) and neuropilin 1 (NP-1) in spinal cord and dorsal root ganglion after partial dorsal root rhizotomy. 15 adult cats were used for this study and divided into 3 groups: normal control group, 7 d and 14 d postoperative groups (7Th day and 14th day groups) undergoing unilateral partial dorsal root rhizotomy. The L3, L5 and L6 segments of spinal cord and L6 dorsal root ganglia (DRG) in operated side were made into frozen sections. By immunohistochemistry ABC method, the sections of spinal cord were stained with specific Sema3A antibody, and L6 DRG were stained with NP-1 antibody. The mean optical density (OD) of Sema3A immunoreactivity in dorsal horn was measured and the number of NP-1 positive medium-small sized neurons in spared DRG was counted. After partial dorsal root rhizotomy, in L3 segment the expression of Sema3A decreased in 7th day group (0.25 +/- 0. 14) compared with that in normal group(0. 37 +/- 0.87) (P P NP-1 positive medium-small sized neurons in spared DRG (30.85 +/- 10.26) was decreased in 7th day group (P P NP-1 in L6 DRG after partial root rhizotomy may be involved in collateral sprouting of spared root in superficial lamina.

  15. Sustained FXN expression in dorsal root ganglia from a nonreplicative genomic HSV-1 vector.

    Science.gov (United States)

    Ventosa, Maria; Wu, Zetang; Lim, Filip

    2017-11-01

    Friedreich's ataxia (FA) is an autosomal recessive neurodegenerative disease caused by mutations in the frataxin gene (FXN), which lead to reduced levels of the essential mitochondrial protein frataxin. Currently, there is no effective cure. With the aim of developing a gene therapy for FA neuropathology, we describe the construction and preliminary characterization of a high-capacity nonreplicative genomic herpes simplex virus type 1 vector (H24B-FXNlac vector) carrying a reduced version of the human FXN genomic locus, comprising the 5-kb promoter and the FXN cDNA with the inclusion of intron 1. We show that the transgene cassette contains the elements necessary to preserve physiological neuronal regulation of human FXN expression. Transduction of cultured fetal rat dorsal root ganglia neurons with the H24B-FXNlac vector results in sustained expression of human FXN transcripts and frataxin protein. Rat footpad inoculation with the H24B-FXNlac vector results in human FXN transgene delivery to the dorsal root ganglia, with expression persisting for at least 1 month. The results of the present study support the feasibility of using this vector for sustained neuronal expression of human frataxin for FA gene therapy. Copyright © 2017 John Wiley & Sons, Ltd.

  16. A Combinatorial Approach to Induce Sensory Axon Regeneration into the Dorsal Root Avulsed Spinal Cord

    DEFF Research Database (Denmark)

    Hoeber, Jan; Konig, Niclas; Trolle, Carl

    2017-01-01

    Spinal root injuries result in newly formed glial scar formation, which prevents regeneration of sensory axons causing permanent sensory loss. Previous studies showed that delivery of trophic factors or implantation of human neural progenitor cells supports sensory axon regeneration and partly...... restores sensory functions. In this study, we elucidate mechanisms underlying stem cell-mediated ingrowth of sensory axons after dorsal root avulsion (DRA). We show that human spinal cord neural stem/progenitor cells (hscNSPC), and also, mesoporous silica particles loaded with growth factor mimetics (Meso......MIM), supported sensory axon regeneration. However, when hscNSPC and MesoMIM were combined, sensory axon regeneration failed. Morphological and tracing analysis showed that sensory axons grow through the newly established glial scar along “bridges” formed by migrating stem cells. Coimplantation of Meso...

  17. Expressing Constitutively Active Rheb in Adult Dorsal Root Ganglion Neurons Enhances the Integration of Sensory Axons that Regenerate Across a Chondroitinase-Treated Dorsal Root Entry Zone Following Dorsal Root Crush.

    Science.gov (United States)

    Wu, Di; Klaw, Michelle C; Kholodilov, Nikolai; Burke, Robert E; Detloff, Megan R; Côté, Marie-Pascale; Tom, Veronica J

    2016-01-01

    While the peripheral branch of dorsal root ganglion neurons (DRG) can successfully regenerate after injury, lesioned central branch axons fail to regrow across the dorsal root entry zone (DREZ), the interface between the dorsal root and the spinal cord. This lack of regeneration is due to the limited regenerative capacity of adult sensory axons and the growth-inhibitory environment at the DREZ, which is similar to that found in the glial scar after a central nervous system (CNS) injury. We hypothesized that transduction of adult DRG neurons using adeno-associated virus (AAV) to express a constitutively-active form of the GTPase Rheb (caRheb) will increase their intrinsic growth potential after a dorsal root crush. Additionally, we posited that if we combined that approach with digestion of upregulated chondroitin sulfate proteoglycans (CSPG) at the DREZ with chondroitinase ABC (ChABC), we would promote regeneration of sensory axons across the DREZ into the spinal cord. We first assessed if this strategy promotes neuritic growth in an in vitro model of the glial scar containing CSPG. ChABC allowed for some regeneration across the once potently inhibitory substrate. Combining ChABC treatment with expression of caRheb in DRG significantly improved this growth. We then determined if this combination strategy also enhanced regeneration through the DREZ after dorsal root crush in adult rats in vivo. After unilaterally crushing C4-T1 dorsal roots, we injected AAV5-caRheb or AAV5-GFP into the ipsilateral C5-C8 DRGs. ChABC or PBS was injected into the ipsilateral dorsal horn at C5-C8 to digest CSPG, for a total of four animal groups (caRheb + ChABC, caRheb + PBS, GFP + ChABC, GFP + PBS). Regeneration was rarely observed in PBS-treated animals, whereas short-distance regrowth across the DREZ was observed in ChABC-treated animals. No difference in axon number or length between the ChABC groups was observed, which may be related to intraganglionic inflammation induced by the

  18. The dorsal root ganglion as a therapeutic target for chronic pain

    NARCIS (Netherlands)

    A.L. Liem (Liong); Van Dongen, E. (Eric); F.J.P.M. Huygen (Frank); P. Staats (Peter); J. Kramer (Jeffery)

    2016-01-01

    textabstractChronic neuropathic pain is a widespread problem with negative personal and societal consequences. Despite considerable clinical neuroscience research, the goal of developing effective, reliable, and durable treatments has remained elusive. The critical role played by the dorsal root

  19. Dorsal root ganglion compression as an animal model of sciatica and low back pain

    OpenAIRE

    Lin, Xiao-Yu; Yang, Jing; LI, HUI-MING; Hu, San-Jue; Xing, Jun-Ling

    2012-01-01

    As sciatica and low back pain are among the most common medical complaints, many studies have duplicated these conditions in animals. Chronic compression of the dorsal root ganglion (CCD) is one of these models. The surgery is simple: after exposing the L4/L5 intervertebral foramina, stainless steel rods are implanted unilaterally, one rod for each vertebra, to chronically compress the lumbar dorsal root ganglion (DRG). Then, CCD can be used to simulate the clinical conditions caused by steno...

  20. Dorsal root ganglia microenvironment of female BB Wistar diabetic rats with mild neuropathy.

    Science.gov (United States)

    Zochodne, D W; Ho, L T; Allison, J A

    1994-12-01

    Abnormalities in the microenvironment of dorsal root ganglia (DRG) might play a role in the pathogenesis of sensory abnormalities in human diabetic neuropathy. We examined aspects of DRG microenvironment by measuring local blood flow and oxygen tension in the L4 dorsal root ganglia of female BB Wistar (BBW) diabetic rats with mild neuropathy. The findings were compared with concurrent measurements of local sciatic endoneurial blood flow and oxygen tension. Diabetic rats were treated with insulin and underwent electrophysiological, blood flow and oxygen tension measurements at either 7-11 or 17-23 weeks after the development of glycosuria. Nondiabetic female BB Wistar rats from the same colony served as controls. At both ages, BBW diabetic rats had significant abnormalities in sensory, but not motor conduction compared to nondiabetic controls. Sciatic endoneurial blood flow in the diabetic rats of both ages was similar to control values, but the older (17-23 week diabetic) BBW diabetic rats had a selective reduction in DRG blood flow. Sciatic endoneurial oxygen tensions were not significantly altered in the diabetic rats. DRG oxygen tension appeared lowered in younger (7-11 week diabetic) but not older (17-23 week diabetic) BBW rats. Our findings indicate that there are important changes in the DRG microenvironment of diabetic rats with selective sensory neuropathy.

  1. Pulsed and continuous radiofrequency current adjacent to the cervical dorsal root ganglion of the rat induces late cellular activity in the dorsal horn.

    NARCIS (Netherlands)

    Zundert, J. van; Louw, A.J. de; Joosten, E.A.J.; Kessels, A.G.H.; Honig, W.; Dederen, P.J.W.C.; Veening, J.G.; Vles, J.S.; Kleef, M. van

    2005-01-01

    BACKGROUND: Pulsed radiofrequency treatment has recently been described as a non-neurodestructive or minimally neurodestructive alternative to radiofrequency heat lesions. In clinical practice long-lasting results of pulsed radiofrequency treatment adjacent to the cervical dorsal root ganglion for

  2. Neurogenic contraction and relaxation of human penile deep dorsal vein

    OpenAIRE

    Segarra, Gloria; Medina, Pascual; Domenech, Cristina; Martínez León, Juan B; Vila, José M.; Aldasoro, Martin; Lluch, Salvador

    1998-01-01

    The aim of the present study was to characterize neurogenic and pharmacological responses of human penile deep dorsal vein and to determine whether the responses are mediated by nitric oxide from neural or endothelial origin.Ring segments of human penile deep dorsal vein were obtained from 22 multiorgan donors during procurement of organs for transplantation. The rings were suspended in organ bath chambers for isometric recording of tension. We then studied the contractile and relaxant respon...

  3. Up-regulation of Robo1 in dorsal root ganglia after sciatic nerve ...

    African Journals Online (AJOL)

    Yomi

    2012-01-05

    Jan 5, 2012 ... peripheral nervous system, this study investigated the expression profile of Robo1 in the dorsal root ganglia (DRG) of adult rats following sciatic nerve transection (SNT). Adult Sprague-Dawley rats that were untreated (n = 8), or received SNT (n = 40), were analyzed. DRG from each treatment group at days.

  4. Up-regulation of Robo1 in dorsal root ganglia after sciatic nerve ...

    African Journals Online (AJOL)

    To better understand the role of Robo in peripheral nervous system, this study investigated the expression profile of Robo1 in the dorsal root ganglia (DRG) of adult rats following sciatic nerve transection (SNT). Adult Sprague-Dawley rats that were untreated (n = 8), or received SNT (n = 40), were analyzed. DRG from each ...

  5. Whole transcriptome expression of trigeminal ganglia compared to dorsal root ganglia in Rattus Norvegicus

    DEFF Research Database (Denmark)

    Kogelman, Lisette Johanna Antonia; Christensen, Rikke Elgaard; Pedersen, Sara Hougaard

    2017-01-01

    The trigeminal ganglia (TG) subserving the head and the dorsal root ganglia (DRG) subserving the rest of the body are homologous handling sensory neurons. Differences exist, as a number of signaling substances cause headache but no pain in the rest of the body. To date, very few genes involved in...

  6. Dorsal root potential produced by a TTX-insensitive micro-circuitry in the turtle spinal cord

    DEFF Research Database (Denmark)

    Russo, R E; Delgado-Lezama, R; Hounsgaard, J

    2000-01-01

    1, The mechanisms underlying the dorsal root potential (DRP) were studied in transverse slices of turtle spinal cord. DRPs were evoked by stimulating one filament in a dorsal root and were recorded from another such filament. 2. The DRP evoked at supramaximal stimulus intensity was reduced...

  7. Comparison of efficacy between dorsal root entry zone lesioning and selective dorsal rhizotomy for spasticity of cerebral origin.

    Science.gov (United States)

    Sitthinamsuwan, Bunpot; Phonwijit, Luckchai; Khampalikit, Inthira; Nitising, Akkapong; Nunta-Aree, Sarun; Suksompong, Sirilak

    2017-12-01

    Severe spasticity adversely affects patient functional status and caregiving. No previous study has compared efficacy between dorsal root entry zone lesioning (DREZL) and selective dorsal rhizotomy (SDR) for reduction of spasticity. This study aimed to investigate the efficacy of DREZL and SDR for attenuating spasticity, and to compare efficacy between these two methods. All patients who underwent DREZL, SDR, or both for treatment of intractable spasticity caused by cerebral pathology at Siriraj Hospital during 2009 to 2016 were recruited. Severity of spasticity was assessed using Modified Ashworth Scale (MAS) and Adductor Tone Rating Scale (ATRS). Ambulatory status was also evaluated. Fifteen patients (13 males) with a mean age of 30.3 ± 17.5 years were included. Eight, six, and one patient underwent DREZL, SDR, and combined cervical DREZL and lumbosacral SDR, respectively. Eight of ten patients with preoperative bed-bound status had postoperative improvement in ambulatory status. Spasticity was significantly reduced in the DREZL group (p SDR group (p SDR was effective in both pediatric and adult spasticity patients. A significantly greater reduction in spasticity as assessed by MAS score (p SDR. DREZL is more effective for reducing spasticity, but is more destructive than SDR. DREZL should be preferred for bed-ridden patients, and SDR for ambulatory patients. Both operations are helpful for improving ambulatory status. Gait improvement was observed only in patients who underwent SDR. Adult patients with spasticity of cerebral origin benefit from SDR.

  8. A Combinatorial Approach to Induce Sensory Axon Regeneration into the Dorsal Root Avulsed Spinal Cord.

    Science.gov (United States)

    Hoeber, Jan; König, Niclas; Trolle, Carl; Lekholm, Emilia; Zhou, Chunfang; Pankratova, Stanislava; Åkesson, Elisabet; Fredriksson, Robert; Aldskogius, Håkan; Kozlova, Elena N

    2017-07-15

    Spinal root injuries result in newly formed glial scar formation, which prevents regeneration of sensory axons causing permanent sensory loss. Previous studies showed that delivery of trophic factors or implantation of human neural progenitor cells supports sensory axon regeneration and partly restores sensory functions. In this study, we elucidate mechanisms underlying stem cell-mediated ingrowth of sensory axons after dorsal root avulsion (DRA). We show that human spinal cord neural stem/progenitor cells (hscNSPC), and also, mesoporous silica particles loaded with growth factor mimetics (MesoMIM), supported sensory axon regeneration. However, when hscNSPC and MesoMIM were combined, sensory axon regeneration failed. Morphological and tracing analysis showed that sensory axons grow through the newly established glial scar along "bridges" formed by migrating stem cells. Coimplantation of MesoMIM prevented stem cell migration, "bridges" were not formed, and sensory axons failed to enter the spinal cord. MesoMIM applied alone supported sensory axons ingrowth, but without affecting glial scar formation. In vitro, the presence of MesoMIM significantly impaired migration of hscNSPC without affecting their level of differentiation. Our data show that (1) the ability of stem cells to migrate into the spinal cord and organize cellular "bridges" in the newly formed interface is crucial for successful sensory axon regeneration, (2) trophic factor mimetics delivered by mesoporous silica may be a convenient alternative way to induce sensory axon regeneration, and (3) a combinatorial approach of individually beneficial components is not necessarily additive, but can be counterproductive for axonal growth.

  9. Expression of alternatively spliced sodium channel alpha-subunit genes. Unique splicing patterns are observed in dorsal root ganglia.

    Science.gov (United States)

    Raymond, Christopher K; Castle, John; Garrett-Engele, Philip; Armour, Christopher D; Kan, Zhengyan; Tsinoremas, Nicholas; Johnson, Jason M

    2004-10-29

    Molecular medicine requires the precise definition of drug targets, and tools are now in place to provide genome-wide information on the expression and alternative splicing patterns of any known gene. DNA microarrays were used to monitor transcript levels of the nine well-characterized alpha-subunit sodium channel genes across a broad range of tissues from cynomolgus monkey, a non-human primate model. Alternative splicing of human transcripts for a subset of the genes that are expressed in dorsal root ganglia, SCN8A (Na(v)1.6), SCN9A (Na(v)1.7), and SCN11A (Na(v)1.9) was characterized in detail. Genomic sequence analysis among gene family paralogs and between cross-species orthologs suggested specific alternative splicing events within transcripts of these genes, all of which were experimentally confirmed in human tissues. Quantitative PCR revealed that certain alternative splice events are uniquely expressed in dorsal root ganglia. In addition to characterization of human transcripts, alternatively spliced sodium channel transcripts were monitored in a rat model for neuropathic pain. Consistent down-regulation of all transcripts was observed, as well as significant changes in the splicing patterns of SCN8A and SCN9A.

  10. Dorsal root activity evoked by stimulation of vagina-cervix-uterus junction in the rat.

    Science.gov (United States)

    Tovar, Anibal; Lara-Garcia, Miguel; Cruz, Yolanda; Pacheco, Pablo

    2013-02-16

    In the present study, we characterized the evoked electrical activity from T(13) to S(2) dorsal roots (DRs) during glass probe-stimulation of the vagina-cervix-uterus junction (VCUJ) of female Wistar rats. The results showed that gentle stimulation of VCUJ evoked high-amplitude electrical activity in L(3) and L(6) DRs. Hypogastric or pelvic nerve transection failed to abolish this activity. L(6)-S(1) spinal trunk transection abolished the high-amplitude electrical activity evoked in L(6) DR, while transection of the lumbosacral trunk blocked the high-amplitude electrical activity evoked in L(3) DR. These data suggest that during copulation, penile intromission likely activates the low-threshold sensory receptors of the VCUJ, thereby evoking sensory neural activity that enters the spinal cord via L(3) and L(6) dorsal roots, whose axons travel through the lumbosacral trunk and pudendal nerve. Copyright © 2013. Published by Elsevier B.V.

  11. Antidromic discharges in dorsal roots of decerebrate cats. II: studies during treadmill locomotion.

    Science.gov (United States)

    Beloozerova, Irina N; Rossignol, Serge

    2004-01-23

    In a previous companion paper [Brain Res. 846 (1999) 87-105] we have shown that the dorsal root activity of a decerebrate cat is composed of both orthodromic and antidromic discharges as determined by spike triggered averaging (STA). Furthermore we have shown that, during fictive locomotion in decerebrate and paralyzed cats, antidromic discharges peak in different parts of locomotion cycle but mainly in the flexion phase. In the present study, we have recorded unit potentials from dorsal rootlets during treadmill locomotion in order to understand better the role of movement-related feedback in the generation of antidromic potentials. The unitary activity of 92 antidromically discharging units was recorded in proximal stumps of cut dorsal roots, and that of 20 such units was recorded in uncut roots using two bipolar Ag/AgCl electrodes in both cases. The activity of 80% (74/92) units in cut filaments and of 70% (14/20) units in uncut ones was phasewise related to stepping movements. The peaks of activity of different units occurred during different phases of the step cycle both in cut and uncut filaments. In most cases, the peak of activity was superimposed upon a background of sustained discharge. After blocking the orthodromic flow in a filament (local anesthesia or distal section), the antidromic discharges continued to peak during the same phase but the rate of the discharges increased. We conclude that movement-related afferent feedback significantly modulates the antidromic discharges in dorsal roots during treadmill locomotion. We suggest that these antidromic discharges have a role in controlling afferent feedback during movement.

  12. Three dimensional-magnetic resonance imaging of dorsal root. Ganglion in lumbosacral disease

    Energy Technology Data Exchange (ETDEWEB)

    Taira, Gaku [Tokyo Medical Coll. (Japan)

    1997-07-01

    Magnetic resonance imaging (MRI) is commonly used for the diagnosis of lumbosacral disease. However, there are certain pitfalls in the use of this imaging technique. In particular, MRI is inadequate for accurate diagnosis of lateral spinal root lesions. Furthermore, it is also difficult to show the root ganglion of both sides on a plane by classical 2D-MRI. Moreover 2D-coronal views do not show several roots in one image because each lumbosacral nerve root is on a different plane. We have developed a new method of three-dimensional MRI (3D-MRI) which enables a stereoscopic view of the spinal cord and both sides of spinal nerve roots in one image. We evaluated three techniques of 3D-MRI, including rapid imaging spin echo (RISE), small tip angle gradient echo (STAGE) and short TI inversion recovery (STIR), in 30 patients with lumbar disc herniation. In a separate anatomical study lumbosacral nerve roots and dorsal root ganglion (DRG) were investigated by 3D-MRI in 20 normal subjects. In a pathophysiological study the use of 3D-MRI defects the signal changes following damage to the spinal nerve roots or ganglion in 70 patients. Our results indicated that the STIR method is the best for identifying abnormalities of the spinal cord, roots and intervertebral disc. It was possible to image the lateral part of damaged nerve roots. The S1 angulations and length were significantly smaller than those of others (p<0.05). The S1 DRG was oval and was the largest. With regard to signal changes in damaged root ganglion, a good correlation between root compression and root edema was detected by basic experiments. We are currently examining the relationship between the damaged root ganglion, pain and sensory disturbance. This study showed that the dorsal root ganglion plays an important role in sensory control of radiculopathy. In conclusion, our new data show a close relationship between sensory loss, pain and DRG finding on 3D-MRI. (author)

  13. Dorsal striatal dopamine, food preference and health perception in humans

    NARCIS (Netherlands)

    Wallace, D.L.; Aarts, E.; Dang, L.C.; Greer, S.M.; Jagust, W.J.; D'Esposito, M.

    2014-01-01

    To date, few studies have explored the neurochemical mechanisms supporting individual differences in food preference in humans. Here we investigate how dorsal striatal dopamine, as measured by the positron emission tomography (PET) tracer [(18)F]fluorometatyrosine (FMT), correlates with food-related

  14. Infrared neural stimulation of human spinal nerve roots in vivo.

    Science.gov (United States)

    Cayce, Jonathan M; Wells, Jonathon D; Malphrus, Jonathan D; Kao, Chris; Thomsen, Sharon; Tulipan, Noel B; Konrad, Peter E; Jansen, E Duco; Mahadevan-Jansen, Anita

    2015-01-01

    Infrared neural stimulation (INS) is a neurostimulation modality that uses pulsed infrared light to evoke artifact-free, spatially precise neural activity with a noncontact interface; however, the technique has not been demonstrated in humans. The objective of this study is to demonstrate the safety and efficacy of INS in humans in vivo. The feasibility of INS in humans was assessed in patients ([Formula: see text]) undergoing selective dorsal root rhizotomy, where hyperactive dorsal roots, identified for transection, were stimulated in vivo with INS on two to three sites per nerve with electromyogram recordings acquired throughout the stimulation. The stimulated dorsal root was removed and histology was performed to determine thermal damage thresholds of INS. Threshold activation of human dorsal rootlets occurred in 63% of nerves for radiant exposures between 0.53 and [Formula: see text]. In all cases, only one or two monitored muscle groups were activated from INS stimulation of a hyperactive spinal root identified by electrical stimulation. Thermal damage was first noted at [Formula: see text] and a [Formula: see text] safety ratio was identified. These findings demonstrate the success of INS as a fresh approach for activating human nerves in vivo and providing the necessary safety data needed to pursue clinically driven therapeutic and diagnostic applications of INS in humans.

  15. Lentiviral gene transfer into the dorsal root ganglion of adult rats

    Directory of Open Access Journals (Sweden)

    Park Frank

    2011-08-01

    Full Text Available Abstract Background Lentivector-mediated gene delivery into the dorsal root ganglion (DRG is a promising method for exploring pain pathophysiology and for genetic treatment of chronic neuropathic pain. In this study, a series of modified lentivector particles with different cellular promoters, envelope glycoproteins, and viral accessory proteins were generated to evaluate the requirements for efficient transduction into neuronal cells in vitro and adult rat DRG in vivo. Results In vitro, lentivectors expressing enhanced green fluorescent protein (EGFP under control of the human elongation factor 1α (EF1α promoter and pseudotyped with the conventional vesicular stomatitis virus G protein (VSV-G envelope exhibited the best performance in the transfer of EGFP into an immortalized DRG sensory neuron cell line at low multiplicities of infection (MOIs, and into primary cultured DRG neurons at higher MOIs. In vivo, injection of either first or second-generation EF1α-EGFP lentivectors directly into adult rat DRGs led to transduction rates of 19 ± 9% and 20 ± 8% EGFP-positive DRG neurons, respectively, detected at 4 weeks post injection. Transduced cells included a full range of neuronal phenotypes, including myelinated neurons as well as both non-peptidergic and peptidergic nociceptive unmyelinated neurons. Conclusion VSV-G pseudotyped lentivectors containing the human elongation factor 1α (EF1α-EGFP expression cassette demonstrated relatively efficient transduction to sensory neurons following direct injection into the DRG. These results clearly show the potential of lentivectors as a viable system for delivering target genes into DRGs to explore basic mechanisms of neuropathic pain, with the potential for future clinical use in treating chronic pain.

  16. Identification of some lectin IB4 binding proteins in rat dorsal root ganglia.

    Science.gov (United States)

    Fullmer, Joseph M; Riedl, Maureen S; Higgins, LeeAnn; Elde, Robert

    2004-08-06

    Lectins are proteins that bind to glycoproteins and glycolipids. The isolectin Griffonia simplicifolia I-B4 (IB4) recognizes terminal alpha-galactose and binds to a subset of small and medium-sized neurons in the dorsal root ganglia (DRG). Using one and two-dimensional gel electrophoresis, we have identified several proteins that bind IB4 in sciatic nerve, dorsal horn, and DRG. Treatment with the enzyme alpha-galactosidase reduces IB4 binding, strongly suggesting the binding is specific for the IB4 epitope. Mass spectrometric analysis of tryptic digests of alpha-galactosidase sensitive bands identified three proteins that bind IB4: the laminin beta 2 chain and the light and medium subunits of neurofilaments.

  17. Direct injection into the dorsal root ganglion: technical, behavioral, and histological observations.

    Science.gov (United States)

    Fischer, Gregory; Kostic, Sandra; Nakai, Hiroyuki; Park, Frank; Sapunar, Damir; Yu, Hongwei; Hogan, Quinn

    2011-07-15

    Direct injection of agents into the dorsal root ganglia (DRGs) offers the opportunity to manipulate sensory neuron function at a segmental level to explore pathophysiology of painful conditions. However, there is no described method that has been validated in detail for such injections in adult rats. We have found that 2 μl of dye injected through a pulled glass pipette directly into the distal DRG, exposed by a minimal foraminotomy, produces complete filling of the DRG with limited extension into the spinal roots. Injection into the spinal nerve required 3 μl to achieve comparable DRG filling, produced preferential spread into the ventral root, and was accompanied by substantial leakage of injected solution from the injection site. Injections into the sciatic nerve of volumes up to 10 μl did not reach the DRG. Transient hypersensitivity to mechanical stimulation at threshold (von Frey) and noxious levels (pin) developed after 2 μl saline injection directly into the DRG that was in part attributable to the surgical exposure procedure alone. Only minimal astrocyte activation in the spinal dorsal horn was evident after DRG saline injections. Injection of adeno-associated virus (AAV) vector conveying green fluorescent protein (GFP) transgene resulted in expression as soon as 1 day after injection into the DRG, including fibers in the spinal dorsal horn and columns. AAV injection into the DRG produced additional thermal hypersensitivity and withdrawal from the stroke of a brush and compromised motor performance. These findings demonstrate a method for selective injection of agents into single DRGs for anatomically restricted actions. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. HeyL Regulates the Number of TrkC Neurons in Dorsal Root Ganglia

    OpenAIRE

    Mukhopadhyay, Abhishek; Jarrett, Jennifer; Chlon, Timothy; Kessler, John A

    2009-01-01

    The basic-helix-loop-helix transcription factor HeyL is expressed at high levels by neural crest progenitor cells (NCPs) that give rise to neurons and glia in dorsal root ganglia (DRG). Since HeyL expression was observed in these NCPs during the period of neurogenesis, we generated HeyL null mutants to help examine the factor’s role in ganglion neuronal specification. Homozygous null mutation of HeyL reduced the number of TrkC+ neurons in DRG at birth including the subpopulation that expresse...

  19. Distribution pattern of dorsal root ganglion neurons synthesizing nitric oxide synthase in different animal species.

    Science.gov (United States)

    Kolesár, Dalibor; Kolesárová, Mária; Kyselovič, Ján

    2017-04-01

    The main aim of the present review is to provide at first a short survey of the basic anatomical description of sensory ganglion neurons in relation to cell size, conduction velocity, thickness of myelin sheath, and functional classification of their processes. In addition, we have focused on discussing current knowledge about the distribution pattern of neuronal nitric oxide synthase containing sensory neurons especially in the dorsal root ganglia in different animal species; hence, there is a large controversy in relation to interpretation of the results dealing with this interesting field of research.

  20. Molecular target size of the vanilloid (capsaicin) receptor in pig dorsal root ganglia

    Energy Technology Data Exchange (ETDEWEB)

    Szallasi, A.; Blumberg, P.M. (National Cancer Institute, Bethesda, MD (USA))

    1991-01-01

    The size of the vanilloid receptor was examined by high-energy radiation inactivation analysis of the binding of ({sup 3}H)resiniferatoxin to pig dorsal root ganglion membranes; it was found to be 270 {plus minus} 25 kDa. This value most likely represents the size of a receptor complex rather than of an individual subunit. Other ligand-gated cation channel complexes have reported molecular weights in this range, e.g. 300 kDa for the acetylcholine receptor.

  1. Autotaxin and lysophosphatidic acid1 receptor-mediated demyelination of dorsal root fibers by sciatic nerve injury and intrathecal lysophosphatidylcholine

    Directory of Open Access Journals (Sweden)

    Aoki Junken

    2010-11-01

    Full Text Available Abstract Background Although neuropathic pain is frequently observed in demyelinating diseases such as Guillain-Barré syndrome and multiple sclerosis, the molecular basis for the relationship between demyelination and neuropathic pain behaviors is poorly understood. Previously, we found that lysophosphatidic acid receptor (LPA1 signaling initiates sciatic nerve injury-induced neuropathic pain and demyelination. Results In the present study, we have demonstrated that sciatic nerve injury induces marked demyelination accompanied by myelin-associated glycoprotein (MAG down-regulation and damage of Schwann cell partitioning of C-fiber-containing Remak bundles in the sciatic nerve and dorsal root, but not in the spinal nerve. Demyelination, MAG down-regulation and Remak bundle damage in the dorsal root were abolished in LPA1 receptor-deficient (Lpar1-/- mice, but these alterations were not observed in sciatic nerve. However, LPA-induced demyelination in ex vivo experiments was observed in the sciatic nerve, spinal nerve and dorsal root, all which express LPA1 transcript and protein. Nerve injury-induced dorsal root demyelination was markedly attenuated in mice heterozygous for autotaxin (atx+/-, which converts lysophosphatidylcholine (LPC to LPA. Although the addition of LPC to ex vivo cultures of dorsal root fibers in the presence of recombinant ATX caused potent demyelination, it had no significant effect in the absence of ATX. On the other hand, intrathecal injection of LPC caused potent dorsal root demyelination, which was markedly attenuated or abolished in atx+/- or Lpar1-/- mice. Conclusions These results suggest that LPA, which is converted from LPC by ATX, activates LPA1 receptors and induces dorsal root demyelination following nerve injury, which causes neuropathic pain.

  2. Systemic daily morphine enhances the analgesic effect of intrathecal dexmedetomidine via up-regulation of alpha 2 adrenergic receptor subtypes A, B and C in dorsal root ganglion and dorsal horn.

    Science.gov (United States)

    Tamagaki, Shinji; Suzuki, Takahiro; Hagihira, Satoshi; Hayashi, Yukio; Mashimo, Takashi

    2010-12-01

     It has been reported that the effect of intrathecally administered α2 adrenergic receptor (α2 AR) agonists is enhanced in mice that are chronically tolerant to systemic morphine. However, contributory factors have not been identified. Here we examined whether repeated systemic morphine affected the analgesic potency of intrathecal dexmedetomidine and the expression of subtype A, B and C α2 AR (α2A, α2B and α2C AR) in the dorsal root ganglion and dorsal horn in mice. After subcutaneous injection of morphine or saline for two weeks, dexmedetomidine was administered intrathecally to evaluate its antinociceptive effect. Also, the α2 AR subtypes and µ-opioid receptor mRNA expression in lumbar dorsal root ganglion was quantified using PCR, and α2A and α2C AR in lumbar dorsal root ganglion and dorsal horn were examined by immunohistochemistry. Daily morphine enhanced the antinociceptive effect of intrathecal dexmedetomidine, increased all the α2 AR subtypes but decreased the µ-opioid receptor mRNA expression in dorsal root ganglion and increased immunoreactivity of α2A and α2C AR in dorsal root ganglion and dorsal horn. These results suggest that systemic daily morphine enhances the analgesic effect of intrathecal dexmedetomidine via up-regulation of the α2A, α2B and α2C AR in lumbar dorsal root ganglion and dorsal horn. © 2010 The Authors. JPP © 2010 Royal Pharmaceutical Society of Great Britain.

  3. Long term effects of lipopolysaccharide on satellite glial cells in mouse dorsal root ganglia

    Energy Technology Data Exchange (ETDEWEB)

    Blum, E. [Laboratory of Experimental Surgery, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem 91240 (Israel); Procacci, P.; Conte, V.; Sartori, P. [Dipartimento di Scienze Biomediche per la Salute, University of Milan, via Mangiagalli 14, I-20133 Milano (Italy); Hanani, M., E-mail: hananim@cc.huji.ac.il [Laboratory of Experimental Surgery, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem 91240 (Israel)

    2017-01-01

    Lipopolysaccharide (LPS) has been used extensively to study neuroinflammation, but usually its effects were examined acutely (24 h<). We have shown previously that a single intraperitoneal LPS injection activated satellite glial cells (SGCs) in mouse dorsal root ganglia (DRG) and altered several functional parameters in these cells for at least one week. Here we asked whether the LPS effects would persist for 1 month. We injected mice with a single LPS dose and tested pain behavior, assessed SGCs activation in DRG using glial fibrillary acidic protein (GFAP) immunostaining, and injected a fluorescent dye intracellularly to study intercellular coupling. Electron microscopy was used to quantitate changes in gap junctions. We found that at 30 days post-LPS the threshold to mechanical stimulation was lower than in controls. GFAP expression, as well as the magnitude of dye coupling among SGCs were greater than in controls. Electron microscopy analysis supported these results, showing a greater number of gap junctions and an abnormal growth of SGC processes. These changes were significant, but less prominent than at 7 days post-LPS. We conclude that a single LPS injection exerts long-term behavioral and cellular changes. The results are consistent with the idea that SGC activation contributes to hyperalgesia. - Highlights: • A single lipopolysaccharides injection activated glia in mouse dorsal root ganglia for 30 days. • This was accompanied by increased communications by gap junctions among glia and by hyperalgesia. • Glial activation and coupling may contribute to chronic pain.

  4. Satellite glial cells in dorsal root ganglia are activated in streptozotocin-treated rodents.

    Science.gov (United States)

    Hanani, Menachem; Blum, Erez; Liu, Shuangmei; Peng, Lichao; Liang, Shangdong

    2014-12-01

    Neuropathic pain is a very common complication in diabetes mellitus (DM), and treatment for it is limited. As DM is becoming a global epidemic it is important to understand and treat this problem. The mechanisms of diabetic neuropathic pain are largely obscure. Recent studies have shown that glial cells are important for a variety of neuropathic pain types, and we investigated what are the changes that satellite glial cells (SGCs) in dorsal root ganglia undergo in a DM type 1 model, induced by streptozotocin (STZ) in mice and rats. We carried out immunohistochemical studies to learn about changes in the activation marker glial fibrillary acidic protein (GFAP) in SGCs. We found that after STZ-treatment the number of neurons surrounded with GFAP-positive SGCs in dorsal root ganglia increased 4-fold in mice and 5-fold in rats. Western blotting for GFAP, which was done only on rats because of the larger size of the ganglia, showed an increase of about 2-fold in STZ-treated rats, supporting the immunohistochemical results. These results indicate for the first time that SGCs are activated in rodent models of DM1. As SGC activation appears to contribute to chronic pain, these results suggest that SGCs may participate in the generation and maintenance of diabetic neuropathic pain, and can serve as a potential therapeutic target. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  5. Highly efficient method for gene delivery into mouse dorsal root ganglia neurons.

    Science.gov (United States)

    Yu, Lingli; Reynaud, Florie; Falk, Julien; Spencer, Ambre; Ding, Yin-Di; Baumlé, Véronique; Lu, Ruisheng; Castellani, Valérie; Yuan, Chonggang; Rudkin, Brian B

    2015-01-01

    The development of gene transfection technologies has greatly advanced our understanding of life sciences. While use of viral vectors has clear efficacy, it requires specific expertise and biological containment conditions. Electroporation has become an effective and commonly used method for introducing DNA into neurons and in intact brain tissue. The present study describes the use of the Neon® electroporation system to transfect genes into dorsal root ganglia neurons isolated from embryonic mouse Day 13.5-16. This cell type has been particularly recalcitrant and refractory to physical or chemical methods for introduction of DNA. By optimizing the culture condition and parameters including voltage and duration for this specific electroporation system, high efficiency (60-80%) and low toxicity (>60% survival) were achieved with robust differentiation in response to Nerve growth factor (NGF). Moreover, 3-50 times fewer cells are needed (6 × 10(4)) compared with other traditional electroporation methods. This approach underlines the efficacy of this type of electroporation, particularly when only limited amount of cells can be obtained, and is expected to greatly facilitate the study of gene function in dorsal root ganglia neuron cultures.

  6. Highly efficient method for gene delivery in mouse dorsal root ganglia neurons

    Directory of Open Access Journals (Sweden)

    Lingli eYu

    2015-02-01

    Full Text Available The development of gene transfection technologies has greatly advanced our understanding of life sciences. While use of viral vectors has clear efficacy, it requires specific expertise and biological containment conditions. Electroporation has become an effective and commonly used method for introducing DNA into neurons and in intact brain tissue. The present study describes the use of the Neon® electroporation system to transfect genes into dorsal root ganglia neurons isolated from embryonic mouse Day 13.5 to 16. This cell type has been particularly recalcitrant and refractory to physical or chemical methods for introduction of DNA. By optimizing the culture condition and parameters including voltage and duration for this specific electroporation system, high efficiency (60 – 80% and low toxicity (> 60% survival were achieved with robust differentiation in response to Nerve growth factor (NGF. Moreover, 3-50 times fewer cells are needed (6x104 compared with other traditional electroporation methods. This approach underlines the efficacy of this type of electroporation, particularly when only limited amount of cells can be obtained, and is expected to greatly facilitate the study of gene function in dorsal root ganglia neuron cultures.

  7. Calcium activity of upper thoracic dorsal root ganglion neurons in zucker diabetic Fatty rats

    DEFF Research Database (Denmark)

    Ghorbani, Marie Louise; Nyborg, Niels C B; Fjalland, Bjarne

    2013-01-01

    or in combination with algogenic chemicals (bradykinin, serotonin, prostaglandin E2 (all 10(-5)¿M), and adenosine (10(-3)¿M)) at pH 7.4 and 6.0. Neurons from diabetic animals exhibited an overall increased response to stimulation with 20¿mM¿K(+) compared to neurons from control. Stimulation with Capsaicin alone...... caused an augmented response in neurons from diabetic animals compared to control animals. When stimulated with a combination of Capsaicin and algogenic chemicals, no differences between the two groups of neurons were measured, neither at pH 7.4 nor 6.0. In conclusion, diabetes-induced alterations......The aim of the present study was to examine the calcium activity of C8-T5 dorsal root ganglion (DRG) neurons from Zucker diabetic fatty rats. In total, 8 diabetic ZDF fatty animals and 8 age-matched control ZDF lean rats were employed in the study. C8-T5 dorsal root ganglia were isolated...

  8. Electrophysiologic changes in dorsal root ganglion neurons and behavioral changes in a lumbar radiculopathy model.

    Science.gov (United States)

    Kirita, Takashi; Takebayashi, Tsuneo; Mizuno, Satoshi; Takeuchi, Hirohito; Kobayashi, Takeshi; Fukao, Mitsuhiro; Yamashita, Toshihiko; Tohse, Noritsugu

    2007-01-15

    The DRG neuron was electrophysiologically investigated using a rat model with constriction of the proximal site of the DRG. To investigate the pathomechanisms of lumbar radiculopathy, we established a rat model with constriction of the proximal site of the DRG. And to characterize the DRG neurons in the rat model of lumbar radiculopathy, the physiologic properties regarding action potential, Na, and K current of the DRG neurons were analyzed through the use of patch clamp recordings. In lumbar root constriction models, properties of secondary afferent neurons in the dorsal horn have been investigated. However, the electrical properties of DRG neuron have not been well investigated. To compare the excitability of DRG neurons between root constriction models and sham, we examined the threshold current, action potential (AP) threshold, resting membrane potential (RMP), afterhyperpolarization (AHP), action potential duration 50 (APD50), action potential amplitude, maximum rise time of AP, and pattern of discharges evoked by depolarizing current. We also examined the peak Na current and steady-state Na and K currents with the voltage clamp technique. The rats in the root constriction group demonstrated mechanical allodynia and thermal hyperalgesia. In measurement of the action potential, lower threshold current, more depolarized RMP, larger AHP, and prolonged APD50 were measured in the root constriction neurons compared with the sham group. The incidence of sustained burst was significantly higher in root constriction neurons. The Na current in root constriction neurons was markedly larger. There were no significant differences in K current density and voltage dependency. The constriction of lumbar root increased excitability and Na current amplitude of DRG neurons. These findings indicate that lumbar radicular pain may be associated with increased excitability of involved DRG neurons.

  9. Regulation of Nav1.7: A Conserved SCN9A Natural Antisense Transcript Expressed in Dorsal Root Ganglia

    Science.gov (United States)

    Koenig, Jennifer; Werdehausen, Robert; Linley, John E.; Habib, Abdella M.; Vernon, Jeffrey; Lolignier, Stephane; Eijkelkamp, Niels; Zhao, Jing; Okorokov, Andrei L.; Woods, C. Geoffrey; Wood, John N.; Cox, James J.

    2015-01-01

    The Nav1.7 voltage-gated sodium channel, encoded by SCN9A, is critical for human pain perception yet the transcriptional and post-transcriptional mechanisms that regulate this gene are still incompletely understood. Here, we describe a novel natural antisense transcript (NAT) for SCN9A that is conserved in humans and mice. The NAT has a similar tissue expression pattern to the sense gene and is alternatively spliced within dorsal root ganglia. The human and mouse NATs exist in cis with the sense gene in a tail-to-tail orientation and both share sequences that are complementary to the terminal exon of SCN9A/Scn9a. Overexpression analyses of the human NAT in human embryonic kidney (HEK293A) and human neuroblastoma (SH-SY5Y) cell lines show that it can function to downregulate Nav1.7 mRNA, protein levels and currents. The NAT may play an important role in regulating human pain thresholds and is a potential candidate gene for individuals with chronic pain disorders that map to the SCN9A locus, such as Inherited Primary Erythromelalgia, Paroxysmal Extreme Pain Disorder and Painful Small Fibre Neuropathy, but who do not contain mutations in the sense gene. Our results strongly suggest the SCN9A NAT as a prime candidate for new therapies based upon augmentation of existing antisense RNAs in the treatment of chronic pain conditions in man. PMID:26035178

  10. A compact dual promoter adeno-associated viral vector for efficient delivery of two genes to dorsal root ganglion neurons

    NARCIS (Netherlands)

    Fagoe, N D; Eggers, R; Verhaagen, J; Mason, M R J

    Adeno-associated viral (AAV) vectors based on serotype 5 are an efficient means to target dorsal root ganglia (DRG) to study gene function in the primary sensory neurons of the peripheral nervous system. In this study, we have developed a compact AAV dual promoter vector composed of the

  11. Homeobox gene expression in adult dorsal root ganglia during sciatic nerve regeneration: is regeneration a recapitulation of development?

    NARCIS (Netherlands)

    Gispen, W.H.; Vogelaar, C.F.; Hoekman, M.F.; Burbach, J.P.H.

    2003-01-01

    After damage of the sciatic nerve, a regeneration process is initiated. Neurons in the dorsal root ganglion regrow their axons and functional connections. The molecular mechanisms of this neuronal regenerative process have remained elusive, but a relationship with developmental processes has been

  12. Neurogenic contraction and relaxation of human penile deep dorsal vein

    Science.gov (United States)

    Segarra, Gloria; Medina, Pascual; Domenech, Cristina; Martínez León, Juan B; Vila, José M; Aldasoro, Martin; Lluch, Salvador

    1998-01-01

    The aim of the present study was to characterize neurogenic and pharmacological responses of human penile deep dorsal vein and to determine whether the responses are mediated by nitric oxide from neural or endothelial origin.Ring segments of human penile deep dorsal vein were obtained from 22 multiorgan donors during procurement of organs for transplantation. The rings were suspended in organ bath chambers for isometric recording of tension. We then studied the contractile and relaxant responses to electrical field stimulation and to vasoactive agents.Electrical field stimulation (0.5–2 Hz) and noradrenaline (3×10−10–3×10−5 M) caused frequency- and concentration-dependent contractions that were of greater magnitude in veins denuded of endothelium. The inhibitor of nitric oxide synthesis NG-nitro-L-arginine methyl ester hydrochloride (L-NAME, 10−4 M) increased the adrenergic responses only in rings with endothelium.In preparations contracted with noradrenaline in the presence of guanethidine (10−6 M) and atropine (10−6 M), electrical stimulation induced frequency-dependent relaxations. This neurogenic relaxation was prevented by L-NAME, methylene blue (3×10−5 M) and tetrodotoxin (10−6 M), but was unaffected by removal of endothelium.Acetylcholine (10−8–3×10−5 M) and substance P (3×10−11–3×10−7 M) induced endothelium-dependent relaxations. In contrast, sodium nitroprusside (10−9–3×10−5 M) and papaverine (10−8–3×10−5 M) caused endothelium-independent relaxations.The results provide functional evidence that the human penile deep dorsal vein is an active component of the penile vascular resistance through the release of nitric oxide from both neural and endothelial origin. Dysfunction in any of these sources of nitric oxide should be considered in some forms of impotence. PMID:9690872

  13. Neuroimmune and Neuropathic Responses of Spinal Cord and Dorsal Root Ganglia in Middle Age.

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    Galbavy, William; Kaczocha, Martin; Puopolo, Michelino; Liu, Lixin; Rebecchi, Mario J

    2015-01-01

    Prior studies of aging and neuropathic injury have focused on senescent animals compared to young adults, while changes in middle age, particularly in the dorsal root ganglia (DRG), have remained largely unexplored. 14 neuroimmune mRNA markers, previously associated with peripheral nerve injury, were measured in multiplex assays of lumbar spinal cord (LSC), and DRG from young and middle-aged (3, 17 month) naïve rats, or from rats subjected to chronic constriction injury (CCI) of the sciatic nerve (after 7 days), or from aged-matched sham controls. Results showed that CD2, CD3e, CD68, CD45, TNF-α, IL6, CCL2, ATF3 and TGFβ1 mRNA levels were substantially elevated in LSC from naïve middle-aged animals compared to young adults. Similarly, LSC samples from older sham animals showed increased levels of T-cell and microglial/macrophage markers. CCI induced further increases in CCL2, and IL6, and elevated ATF3 mRNA levels in LSC of young and middle-aged adults. Immunofluorescence images of dorsal horn microglia from middle-aged naïve or sham rats were typically hypertrophic with mostly thickened, de-ramified processes, similar to microglia following CCI. Unlike the spinal cord, marker expression profiles in naïve DRG were unchanged across age (except increased ATF3); whereas, levels of GFAP protein, localized to satellite glia, were highly elevated in middle age, but independent of nerve injury. Most neuroimmune markers were elevated in DRG following CCI in young adults, yet middle-aged animals showed little response to injury. No age-related changes in nociception (heat, cold, mechanical) were observed in naïve adults, or at days 3 or 7 post-CCI. The patterns of marker expression and microglial morphologies in healthy middle age are consistent with development of a para-inflammatory state involving microglial activation and T-cell marker elevation in the dorsal horn, and neuronal stress and satellite cell activation in the DRG. These changes, however, did not

  14. Neuroimmune and Neuropathic Responses of Spinal Cord and Dorsal Root Ganglia in Middle Age.

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    William Galbavy

    Full Text Available Prior studies of aging and neuropathic injury have focused on senescent animals compared to young adults, while changes in middle age, particularly in the dorsal root ganglia (DRG, have remained largely unexplored. 14 neuroimmune mRNA markers, previously associated with peripheral nerve injury, were measured in multiplex assays of lumbar spinal cord (LSC, and DRG from young and middle-aged (3, 17 month naïve rats, or from rats subjected to chronic constriction injury (CCI of the sciatic nerve (after 7 days, or from aged-matched sham controls. Results showed that CD2, CD3e, CD68, CD45, TNF-α, IL6, CCL2, ATF3 and TGFβ1 mRNA levels were substantially elevated in LSC from naïve middle-aged animals compared to young adults. Similarly, LSC samples from older sham animals showed increased levels of T-cell and microglial/macrophage markers. CCI induced further increases in CCL2, and IL6, and elevated ATF3 mRNA levels in LSC of young and middle-aged adults. Immunofluorescence images of dorsal horn microglia from middle-aged naïve or sham rats were typically hypertrophic with mostly thickened, de-ramified processes, similar to microglia following CCI. Unlike the spinal cord, marker expression profiles in naïve DRG were unchanged across age (except increased ATF3; whereas, levels of GFAP protein, localized to satellite glia, were highly elevated in middle age, but independent of nerve injury. Most neuroimmune markers were elevated in DRG following CCI in young adults, yet middle-aged animals showed little response to injury. No age-related changes in nociception (heat, cold, mechanical were observed in naïve adults, or at days 3 or 7 post-CCI. The patterns of marker expression and microglial morphologies in healthy middle age are consistent with development of a para-inflammatory state involving microglial activation and T-cell marker elevation in the dorsal horn, and neuronal stress and satellite cell activation in the DRG. These changes, however

  15. Synaptic plasticity and sensory-motor improvement following fibrin sealant dorsal root reimplantation and mononuclear cell therapy

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    Suzana Ulian Benitez

    2014-09-01

    Full Text Available Root lesions may affect both dorsal and ventral roots. However, due to the possibility of generating further inflammation and neuropathic pain, surgical procedures do not prioritize the repair of the afferent component. The loss of such sensorial input directly disturbs the spinal circuits thus affecting the functionality of the injuried limb. The present study evaluated the motor and sensory improvement following dorsal root reimplantation with fibrin sealant (FS plus bone marrow mononuclear cells (MC after dorsal rhizotomy. MC were used to enhance the repair process. We also analyzed changes in the glial response and synaptic circuits within the spinal cord. Female Lewis rats (6-8 weeks old were divided in three groups: rhizotomy (RZ group, rhizotomy repaired with FS (RZ+FS group and rhizotomy repaired with FS and MC (RZ+FS+MC group. The behavioral tests electronic von-Frey and Walking track test were carried out. For immunohistochemistry we used markers to detect different synapse profiles as well as glial reaction. The behavioral results showed a significant decrease in sensory and motor function after lesion. The reimplantation decreased glial reaction and improved synaptic plasticity of afferent inputs. Cell therapy further enhanced the rewiring process. In addition, both reimplanted groups presented twice as much motor control compared to the non-treated group. In conclusion, the reimplantation with FS and MC is efficient and may be considered an approach to improve sensory-motor recovery following dorsal rhizotomy.

  16. Pulsed Radiofrequency to the Dorsal Root Ganglion in Acute Herpes Zoster and Postherpetic Neuralgia.

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    Kim, Koohyun; Jo, Daehyun; Kim, EungDon

    2017-03-01

    Latent varicella zoster virus reactivates mainly in sensory ganglia such as the dorsal root ganglion (DRG) or trigeminal ganglion. The DRG contains many receptor channels and is an important region for pain signal transduction. Sustained abnormal electrical activity to the spinal cord via the DRG in acute herpes zoster can result in neuropathic conditions such as postherpetic neuralgia (PHN). Although the efficacy of pulsed radiofrequency (PRF) application to the DRG in various pain conditions has been previously reported, the application of PRF to the DRG in patients with herpes zoster has not yet been studied. The aim of the present study was to compare the clinical effects of PRF to the DRG in patients with herpes zoster to those of PRF to the DRG in patients with PHN. Retrospective comparative study. University hospital pain center in Korea. The medical records of 58 patients who underwent PRF to the DRG due to zoster related pain (herpes zoster or PHN) were retrospectively analyzed. Patients were divided into 2 groups according to the timing of PRF after zoster onset: an early PRF group (within 90 days) and a PHN PRF group (more than 90 days). The efficacy of PRF was assessed by a numeric rating scale (NRS) and by recording patient medication doses before PRF and at one week, 4 weeks, 8 weeks, and 12 weeks after PRF. Pain intensity was decreased after PRF in all participants. However, the degree of pain reduction was significantly higher in the early PRF group. Moreover, more patients discontinued their medication in the early PRF group, and the PRF success rate was also higher in the early PRF group. The relatively small sample size from a single center, short duration of review of medical records, and the retrospective nature of the study. PRF to the DRG is a useful treatment for treatment-resistant cases of herpes zoster and PHN. Particularly in herpes zoster patients with intractable pain, application of PRF to the DRG should be considered for pain control

  17. [Effect of triptolide on iNOS and SP expressions in spinal dorsal horn and dorsal root ganglion of rats with adjuvant arthritis].

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    Chen, Wei; Zhang, Xu-Dong; Lu, Zhuo-Hui; Wei, Deng-Ming

    2014-05-01

    To observe the analgesic effect of triptolide (TP) of high, middle and low doses on rats with adjuvant arthritis (AA), and the expressions of inducible nitric oxide synthase (iNOS) and substance P (SP) in spinal dorsal horn and dorsal root ganglion (DRG) of corresponding sections, in order to discuss the possible mechanism for the analgesic effect of TP on rats with adjuvant arthritis. Fifty SD rats were selected and randomly divided into the normal group (group A), the model group (group B), and TP low (group C), middle (group D), high (group E) dose groups. Except for the group A, all of the remaining groups were injected with 0.1 mL of Freund's complete adjuvant through their right rear toes to establish the model. At 14 d after the model establishment, rats in C, D and E groups were intraperitoneally injected with different doses of TP (0.1 mg x kg(-1) for the group C, 0.2 mg x kg(-1) for the group D, 0.4 mg x kg(-1) for the group E) once a day for 9 days. Then the 50% mechanical withdraw threshold (MWT) was determined. And the expressions of iNOS and SP in lumbar5 (L5) spinal dorsal horn and DRG were detected with the immunohistochemical method. The 50% MWT of rats in the group B was significantly lower than that of the group A (P effect relationship. The immunohistochemical results indicated that the iNOS and SP expressions significantly increased in the group B (P effect relationship. TP shows a good analgesic effect on AA, and could inhibit the iNOS and SP expressions in spinal dorsal horn and DRG in rats with adjuvant arthritis, which may be one of action mechanisms for the analgesic effect of TP.

  18. Localized and non-contact mechanical stimulation of dorsal root ganglion sensory neurons using scanning ion conductance microscopy.

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    Sánchez, Daniel; Anand, Uma; Gorelik, Julia; Benham, Christopher D; Bountra, Chas; Lab, Max; Klenerman, David; Birch, Rolfe; Anand, Praveen; Korchev, Yuri

    2007-01-15

    Mechanosensitive ion channels convert external mechanical force into electrical and chemical signals in cells, but their physiological function in different tissues is not clearly understood. One reason for this is that there is as yet no satisfactory physiological method to stimulate these channels in living cells. Using the nanopipette-probe of the Scanning Ion Conductance Microscope (SICM), we have developed a new technique to apply local mechanical stimulus to living cells to an area of about 0.385 microm2, determined by the pipette diameter. Our method prevents any physical contact and damage to the cell membrane by use of a pressure jet applied via the nanopipette. The study used whole-cell patch-clamp recordings and measurements of intracellular Ca2+ concentration to validate the application of the mechanical stimulation protocols in human and rat dorsal root ganglia (DRG) sensory neurons. We were able, for the first time, to produce a non-contact, controlled mechanical stimulation on living neurites of human DRG neurons. Our methods will enable the identification and characterisation of compounds being developed for the treatment of clinical mechanical hypersensitivity states.

  19. Effects of free fatty acids on sodium currents in rat dorsal root ganglion neurons.

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    Hong, Min-Pyo; Kim, Hong Im; Shin, Yong Kyoo; Lee, Chung Soo; Park, Mijung; Song, Jin-Ho

    2004-05-15

    Free fatty acids (FFAs), especially polyunsaturated fatty acids (PUFAs), are potent modulators of muscle-type sodium channels. It is not known if they also modulate sodium channels of sensory neurons. In this study, we investigated the effects of FFAs on the fast tetrodotoxin-sensitive (fTTX-S) and the slow tetrodotoxin-resistant (sTTX-R) sodium currents in rat dorsal root ganglion neurons. At a holding potential of -80 mV, PUFAs potently inhibited fTTX-S current, but monounsaturated fatty acids (MUFAs) and saturated fatty acids (SFAs) to a lesser extent. All FFAs initially increased sTTX-R current, and then decreased it slightly. PUFAs and MUFAs produced a hyperpolarizing shift of the steady-state inactivation voltage for both types of sodium currents. The shift generally increased with the number of unsaturated bonds. FFAs did not change the maximum amplitude of fTTX-S current, but increased that of sTTX-R current. Most FFAs shifted the activation voltage for fTTX-S current in the hyperpolarizing direction, which was not dependent on the degree of unsaturation. MUFAs and SFAs shifted the activation voltage for sTTX-R current in the hyperpolarizing direction, but PUFAs were without effect. The modulation of sodium currents by FFAs, especially PUFAs, may have considerable impact on the excitability of sensory neurons.

  20. The role of the transcription factor Rbpj in the development of dorsal root ganglia

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    Chen Jia-Yin

    2011-04-01

    Full Text Available Abstract Background The dorsal root ganglion (DRG is composed of well-characterized populations of sensory neurons and glia derived from a common pool of neural crest stem cells (NCCs, and is a good system to study the mechanisms of neurogenesis and gliogenesis. Notch signaling is known to play important roles in DRG development, but the full scope of Notch functions in mammalian DRG development remains poorly understood. Results In the present study, we used Wnt1-Cre to conditionally inactivate the transcription factor Rbpj, a critical integrator of activation signals from all Notch receptors, in NCCs and their derived cells. Deletion of Rbpj caused the up-regulation of NeuroD1 and precocious neurogenesis in DRG early development but led to an eventual deficit of sensory neurons at later stages, due to reduced cell proliferation and abnormal cell death. In addition, gliogenesis was delayed initially, but a near-complete loss of glia was observed finally in Rbpj-deficient DRG. Furthermore, we found P75 and Sox10, which are normally expressed exclusively in neuronal and glial progenitors of the DRG after the NCCs have completed their migration, were co-expressed in many cells of the DRG of Rbpj conditional knock-out mice. Conclusions Our data indicate that Rbpj-mediated canonical Notch signaling inhibits DRG neuronal differentiation, possibly by regulating NeuroD1 expression, and is required for DRG gliogenesis in vivo.

  1. Postembryonic neuronal addition in Zebrafish dorsal root ganglia is regulated by Notch signaling

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    McGraw Hillary

    2012-06-01

    Full Text Available Abstract Background The sensory neurons and glia of the dorsal root ganglia (DRG arise from neural crest cells in the developing vertebrate embryo. In mouse and chick, DRG formation is completed during embryogenesis. In contrast, zebrafish continue to add neurons and glia to the DRG into adulthood, long after neural crest migration is complete. The molecular and cellular regulation of late DRG growth in the zebrafish remains to be characterized. Results In the present study, we use transgenic zebrafish lines to examine neuronal addition during postembryonic DRG growth. Neuronal addition is continuous over the period of larval development. Fate-mapping experiments support the hypothesis that new neurons are added from a population of resident, neural crest-derived progenitor cells. Conditional inhibition of Notch signaling was used to assess the role of this signaling pathway in neuronal addition. An increase in the number of DRG neurons is seen when Notch signaling is inhibited during both early and late larval development. Conclusions Postembryonic growth of the zebrafish DRG comes about, in part, by addition of new neurons from a resident progenitor population, a process regulated by Notch signaling.

  2. Neuronal somatic ATP release triggers neuron-satellite glial cell communication in dorsal root ganglia.

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    Zhang, X; Chen, Y; Wang, C; Huang, L-Y M

    2007-06-05

    It has been generally assumed that the cell body (soma) of a neuron, which contains the nucleus, is mainly responsible for synthesis of macromolecules and has a limited role in cell-to-cell communication. Using sniffer patch recordings, we show here that electrical stimulation of dorsal root ganglion (DRG) neurons elicits robust vesicular ATP release from their somata. The rate of release events increases with the frequency of nerve stimulation; external Ca(2+) entry is required for the release. FM1-43 photoconversion analysis further reveals that small clear vesicles participate in exocytosis. In addition, the released ATP activates P2X7 receptors in satellite cells that enwrap each DRG neuron and triggers the communication between neuronal somata and glial cells. Blocking L-type Ca(2+) channels completely eliminates the neuron-glia communication. We further show that activation of P2X7 receptors can lead to the release of tumor necrosis factor-alpha (TNFalpha) from satellite cells. TNFalpha in turn potentiates the P2X3 receptor-mediated responses and increases the excitability of DRG neurons. This study provides strong evidence that somata of DRG neurons actively release transmitters and play a crucial role in bidirectional communication between neurons and surrounding satellite glial cells. These results also suggest that, contrary to the conventional view, neuronal somata have a significant role in cell-cell signaling.

  3. Tlx3 Function in the Dorsal Root Ganglion is Pivotal to Itch and Pain Sensations

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    Chengcheng Huang

    2017-06-01

    Full Text Available Itch, a sensation eliciting a desire to scratch, is distinct from but not completely independent of pain. Inspiring achievements have been made in the characterization of itch-related receptors and neurotransmitters, but the molecular mechanisms controlling the development of pruriceptors remain poorly understood. Here, our RNAseq and in situ hybridization data show that the transcription factor Tlx3 is required for the expression of a majority of itch-related molecules in the dorsal root ganglion (DRG. As a result, Tlx3F/F;Nav1.8-cre mice exhibit significantly attenuated acute and dry skin-induced chronic itch. Furthermore, our study indicates that TRPV1 plays a pivotal role in the chronic itch evoked by dry skin and allergic contact dermatitis (ACD. The mutants also display impaired response to cold and inflammatory pain and elevated response to capsaicin, whereas the responses to acute mechanical, thermal stimuli and neuropathic pain remain normal. In Tlx3F/F;Nav1.8-cre mice, TRPV1 is derepressed and expands predominantly into IB4+ non-peptidergic (NP neurons. Collectively, our data reveal a molecular mechanism in regulating the development of pruriceptors and controlling itch and pain sensations.

  4. Sialic acid contributes to hyperexcitability of dorsal root ganglion neurons in rats with peripheral nerve injury.

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    Peng, Xiao-Qing; Zhang, Xiu-Lin; Fang, Yan; Xie, Wen-Rui; Xie, Yi-Kuan

    2004-11-12

    Axonal injury of the dorsal root ganglion (DRG) neurons may alter the synthesis of certain membrane proteins that are responsible for the development of abnormal hyperexcitability. The external domains of most of these membrane proteins are sialylated. Because sialic acid carries heavy negative charges, the increase of sialylated proteins may increase neurons' negative surface charges, which will have predictable effects on the voltage-gated channels, and affect the excitability of injured neurons. Using intracellular electrophysiological recording, we demonstrated that following chronic constriction injury (CCI) of the sciatic nerve, Aalpha/beta DRG neurons become hyperexcitable, as indicated by a more depolarized resting membrane potential (Vm) and a lowered threshold current (TIC). More interestingly, the excitability of injured DRG neurons was reduced substantially when the extracellular sialic acid was removed by pretreatment with neuraminidase. The Vm was less depolarized and the TIC increased robustly as compared to the CCI neurons without neuraminidase treatment. However, desialylation of normal, intact neurons had no significant effect on the Vm and less effect on the TIC. Our results suggest that the hyperexcitability of injured sensory neurons may be associated with increased negatively charged sialic acid residues on the surface of the neuronal somata.

  5. Roles of syndecan-4 and relative kinases in dorsal root ganglion neuron adhesion and mechanotransduction.

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    Lin, Tzu-Jou; Lu, Kung-Wen; Chen, Wei-Hsin; Cheng, Chao-Min; Lin, Yi-Wen

    2015-04-10

    Mechanical stimuli elicit a biological response and initiate complex physiological processes, including neural feedback schemes associated with senses such as pain, vibration, touch, and hearing. The syndecans (SDCs), a group of adhesion receptors, can modulate adhesion and organize the extracellular matrix (ECM). In this study, we cultured dorsal root ganglia (DRG) on controlled polydimethylsiloxane (PDMS) substrates coated with poly-l-lysine (poly) or fibronectin (FN) to investigate cell adhesion and mechanotransduction mechanisms by mechanical stretching on PDMS using DRG neurons. Our results demonstrated that neuronal density, neurite length, and neurite branching were lower in the PDMS group and could be further reversed through activating SDC-4 by FN. The expression of the SDC-4 pathway decreased but with increased pPKCα in the PDMS-poly group. After mechanical stretching, pPKCα-FAKpTyr397-pERK1/2 expression was increased in both poly- and FN-coated PDMS. These results indicate that SDC4-pPKCα-FAKpTyr397-pERK1/2 may play a crucial role in DRG adhesion and mechanotransduction. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Orexin affects dorsal root ganglion neurons: a mechanism for regulating the spinal nociceptive processing.

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    Yan, J-A; Ge, L; Huang, W; Song, B; Chen, X-W; Yu, Z-P

    2008-01-01

    Orexins (orexin A and B) are initially known to be a hypothalamic peptide critical for feeding and normal wakefulness. In addition, emerging evidence from behavioral tests suggests that orexins are also involved in the regulation of nociceptive processing, suggesting a novel potential therapeutic approach for pain treatment. Both spinal and supraspinal mechanisms appear to contribute to the role of orexin in nociception. In the spinal cord, dorsal root ganglion (DRG) neurons are primary afferent neurons that transmit peripheral stimuli to the pain-processing areas. Morphological results show that both orexin A and orexin-1 receptor are distributed in DRG neurons. Moreover, by using whole-cell patch-clamp recordings and calcium imaging measurements we found that orexin A induced excitability and intracellular calcium concentration elevation in the isolated rat DRG neurons, which was mainly dependent on the activation of spinal orexin-1 receptor. Based on these findings, we propose a hypothesis that the direct effect of orexin A on DRG neurons would represent a possible mechanism for the orexinergic modulation of spinal nociceptive transmission.

  7. Cervical Spinal Cord and Dorsal Nerve Root Stimulation for Neuropathic Upper Limb Pain.

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    Levine, Adrian B; Parrent, Andrew G; MacDougall, Keith W

    2017-01-01

    Spinal cord stimulation (SCS) is a well-established treatment for chronic neuropathic pain in the lower limbs. Upper limb pain comprises a significant proportion of neuropathic pain patients, but is often difficult to target specifically and consistently with paresthesias. We hypothesized that the use of dorsal nerve root stimulation (DNRS), as an option along with SCS, would help us better relieve pain in these patients. All 35 patients trialed with spinal stimulation for upper limb pain between July 1, 2011, and October 31, 2013, were included. We performed permanent implantation in 23/35 patients based on a visual analogue scale pain score decrease of ≥50% during trial stimulation. Both the SCS and DNRS groups had significant improvements in average visual analogue scale pain scores at 12 months compared with baseline, and the majority of patients in both groups obtained ≥50% pain relief. The majority of patients in both groups were able to reduce their opioid use, and on average had improvements in Short Form-36 quality of life scores. Complication rates did not differ significantly between the two groups. Treatment with SCS or DNRS provides meaningful long-term relief of chronic neuropathic pain in the upper limbs.

  8. CaMK II γ down regulation protects dorsal root ganglion neurons from ropivacaine hydrochloride neurotoxicity.

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    Wen, Xian-Jie; Li, Xiao-Hong; Li, Heng; Liang, Hua; Yang, Chen-Xiang; Wang, Han-Bing

    2017-07-12

    T-type calcium channels are intimately involved in the local anesthetics neurotoxicity. Does CaMKIIγ regulate T-type calcium currents in local anesthetics neurotoxicity? This study generated pAd-CaMKIIγ and pAd-shRNA adenovirus vectors to up- and down-regulate CaMKIIγ mRNA expression in dorsal root ganglion neurons (DRG). Normal DRG (Normal group), empty vector DRG (Empty vector group), pAd-CaMKIIγ DRG (pAd-CaMKIIγ group) and pAd-shRNA DRG (pAd-shRNA group) were treated or untreated with 3 mM ropivacaine hydrochloride for 4 h. Cell viability, apoptosis rate, CaMKIIγ, pCaMKIIγ, Cav3.2, and Cav3.3 expression were detected. Ultrastructural changes in DRG were observed under a transmission electron microscope. The results demonstrated that the cell viability of DRG treated with ropivacaine hydrochloride decreased markedly, the apoptosis rate, CaMKIIγ, pCaMKIIγ, Cav3.2, Cav3.3 expression increased significantly. CaMKIIγ up-regulation aggravated ropivacaine hydrochloride-induced cell damage and increased Cav3.2 and Cav3.3 expression. In conclusion, CaMKIIγ regulated Cav3.2 and Cav3.3 expression in DRG, which was involved with ropivacaine hydrochloride-induced cell injury.

  9. Targeting dorsal root ganglia and primary sensory neurons for the treatment of chronic pain.

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    Berta, Temugin; Qadri, Yawar; Tan, Ping-Heng; Ji, Ru-Rong

    2017-07-01

    Currently the treatment of chronic pain is inadequate and compromised by debilitating central nervous system side effects. Here we discuss new therapeutic strategies that target dorsal root ganglia (DRGs) in the peripheral nervous system for a better and safer treatment of chronic pain. Areas covered: The DRGs contain the cell bodies of primary sensory neurons including nociceptive neurons. After painful injuries, primary sensory neurons demonstrate maladaptive molecular changes in DRG cell bodies and in their axons. These changes result in hypersensitivity and hyperexcitability of sensory neurons (peripheral sensitization) and are crucial for the onset and maintenance of chronic pain. We discuss the following new strategies to target DRGs and primary sensory neurons as a means of alleviating chronic pain and minimizing side effects: inhibition of sensory neuron-expressing ion channels such as TRPA1, TRPV1, and Nav1.7, selective blockade of C- and Aβ-afferent fibers, gene therapy, and implantation of bone marrow stem cells. Expert opinion: These peripheral pharmacological treatments, as well as gene and cell therapies, aimed at DRG tissues and primary sensory neurons can offer better and safer treatments for inflammatory, neuropathic, cancer, and other chronic pain states.

  10. Global analysis of transcriptome in dorsal root ganglia following peripheral nerve injury in rats.

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    Gong, Leilei; Wu, Jiancheng; Zhou, Songlin; Wang, Yaxian; Qin, Jing; Yu, Bin; Gu, Xiaosong; Yao, Chun

    2016-09-09

    Peripheral nervous system has intrinsic regeneration ability after injury, accompanied with the coordination of numerous cells, molecules and signaling pathways. These post-injury biological changes are complex with insufficient understanding. Thus, to obtain a global perspective of changes following nerve injury and to elucidate the mechanisms underlying nerve regeneration are of great importance. By RNA sequencing, we detected transcriptional changes in dorsal root ganglia (DRG) neurons at 0 h, 3 h, 9 h, 1 d, 4 d and 7 d following sciatic nerve crush injury in rats. Differentially expressed genes were then selected and classified into major clusters according to their expression patterns. Cluster 2 (with genes high expressed before 9 h and then down expressed) and cluster 6 (combination of cluster 4 and 5 with genes low expressed before 1 d and then up expressed) were underwent GO annotation and KEGG pathway analysis. Gene act networks were then constructed for these two clusters and the expression of pivotal genes was validated by quantitative real-time PCR. This study provided valuable information regarding the transcriptome changes in DRG neurons following nerve injury, identified potential genes that could be used for improving axon regeneration after nerve injury, and facilitated to elucidate the biological process and molecular mechanisms underlying peripheral nerve injury. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Differential transcriptional profiling of damaged and intact adjacent dorsal root ganglia neurons in neuropathic pain.

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    A K Reinhold

    Full Text Available Neuropathic pain, caused by a lesion in the somatosensory system, is a severely impairing mostly chronic disease. While its underlying molecular mechanisms are not thoroughly understood, neuroimmune interactions as well as changes in the pain pathway such as sensitization of nociceptors have been implicated. It has been shown that not only are different cell types involved in generation and maintenance of neuropathic pain, like neurons, immune and glial cells, but, also, intact adjacent neurons are relevant to the process. Here, we describe an experimental approach to discriminate damaged from intact adjacent neurons in the same dorsal root ganglion (DRG using differential fluorescent neuronal labelling and fluorescence-activated cell sorting (FACS. Two fluorescent tracers, Fluoroemerald (FE and 1-dioctadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate (DiI, were used, whose properties allow us to distinguish between damaged and intact neurons. Subsequent sorting permitted transcriptional analysis of both groups. Results and qPCR validation show a strong regulation in damaged neurons versus contralateral controls as well as a moderate regulation in adjacent neurons. Data for damaged neurons reveal an mRNA expression pattern consistent with established upregulated genes like galanin, which supports our approach. Moreover, novel genes were found strongly regulated such as corticotropin-releasing hormone (CRH, providing novel targets for further research. Differential fluorescent neuronal labelling and sorting allows for a clear distinction between primarily damaged neuropathic neurons and "bystanders," thereby facilitating a more detailed understanding of their respective roles in neuropathic processes in the DRG.

  12. Chronic monitoring of lower urinary tract activity via a sacral dorsal root ganglia interface

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    Khurram, Abeer; Ross, Shani E.; Sperry, Zachariah J.; Ouyang, Aileen; Stephan, Christopher; Jiman, Ahmad A.; Bruns, Tim M.

    2017-06-01

    Objective. Our goal is to develop an interface that integrates chronic monitoring of lower urinary tract (LUT) activity with stimulation of peripheral pathways. Approach. Penetrating microelectrodes were implanted in sacral dorsal root ganglia (DRG) of adult male felines. Peripheral electrodes were placed on or in the pudendal nerve, bladder neck and near the external urethral sphincter. Supra-pubic bladder catheters were implanted for saline infusion and pressure monitoring. Electrode and catheter leads were enclosed in an external housing on the back. Neural signals from microelectrodes and bladder pressure of sedated or awake-behaving felines were recorded under various test conditions in weekly sessions. Electrodes were also stimulated to drive activity. Main results. LUT single- and multi-unit activity was recorded for 4-11 weeks in four felines. As many as 18 unique bladder pressure single-units were identified in each experiment. Some channels consistently recorded bladder afferent activity for up to 41 d, and we tracked individual single-units for up to 23 d continuously. Distension-evoked and stimulation-driven (DRG and pudendal) bladder emptying was observed, during which LUT sensory activity was recorded. Significance. This chronic implant animal model allows for behavioral studies of LUT neurophysiology and will allow for continued development of a closed-loop neuroprosthesis for bladder control.

  13. Catecholamines reduce transient receptor potential vanilloid type 1 desensitization in cultured dorsal root ganglia neurons.

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    Filippi, A; Caruntu, C; Gheorghe, R O; Deftu, A; Amuzescu, B; Ristoiu, V

    2016-12-01

    Sympathetic nervous system and adrenergic receptors are involved in the modulation of dorsal root ganglia neuronal activity, with TRPV1 receptor as an important downstream effector. It is already known that adrenergic sensitization of TRPV1 receptors or catecholamine-induced TRPV1 upregulation are involved in increased excitability and pain via mainly α 1 adrenergic receptors, but it is not known if reduced TRPV1 desensitization is involved in this process, as well. Therefore, the aims of this study were to evaluate the effects of epinephrine and norepinephrine on TRPV1 desensitization induced by repeated applications of capsaicin and to assess what would be the involvement of the major α 1 , α 2 and β adrenergic receptor subtypes. Using calcium microfluorimetry, the effects were evaluated by exposure to 1 μM epinephrine or 10 μM norepinephrine, alone or in the presence of adrenergic receptor inhibitors (phentolamine, prazosin and propranolol) before a 4 th capsaicin application in a series of 5 consecutive capsaicin applications. The results showed that both catecholamines produced significant reduction of TRPV1 desensitization, which was mediated by α 1 , α 2 and β 2 receptors. This study completes the general information about TRPV1 sensitization via adrenergic stimulation and may open perspectives for novel pharmacological approaches in skin inflammatory disorders and pain therapy.

  14. Alterations in the vascular architecture of the dorsal root ganglia in a rat neuropathic pain model.

    Science.gov (United States)

    Kubícek, Lubos; Kopácik, Roman; Klusáková, Ilona; Dubový, Petr

    2010-04-20

    An alteration in the structural arrangement of blood vessels identified by RECA immunohistochemistry was studied in a rat L4 dorsal root ganglia (L4-DRG) neuropathic pain model. We compared a three-dimensional (3-D) reconstruction of the vascular architecture surrounding bodies of the primary sensory neurons in the L4-DRG of naïve rats with that of rats that had surgically undergone unilateral sciatic nerve ligature. Rhodamine-conjugated dextran (Fluoro-Ruby) was used for retrograde labelling of neurons, the axons of which had been injured by nerve ligature. In contrast to DRG from naïve rats and contralateral DRG from operated rats, an increased proportion of RECA+ vascular area and the appearance of nest-like arrangements of blood vessels around neuronal bodies with injured axons were observed in L4-DRG ipsilateral to the sciatic nerve ligature. Fractal analysis confirmed a higher degree of vascular branching, irregularity, and tortuosity in L4-DRG related with sciatic nerve injury. The results suggest that nerve injury induces changes in vascular architecture in associated DRG. Copyright 2010 Elsevier GmbH. All rights reserved.

  15. Na+ Channel Scn1b Gene Regulates Dorsal Root Ganglion Nociceptor Excitability in Vivo*

    Science.gov (United States)

    Lopez-Santiago, Luis F.; Brackenbury, William J.; Chen, Chunling; Isom, Lori L.

    2011-01-01

    Nociceptive dorsal root ganglion (DRG) neurons express tetrodotoxin-sensitive (TTX-S) and -resistant (TTX-R) Na+ current (INa) mediated by voltage-gated Na+ channels (VGSCs). In nociceptive DRG neurons, VGSC β2 subunits, encoded by Scn2b, selectively regulate TTX-S α subunit mRNA and protein expression, ultimately resulting in changes in pain sensitivity. We hypothesized that VGSCs in nociceptive DRG neurons may also be regulated by β1 subunits, encoded by Scn1b. Scn1b null mice are models of Dravet Syndrome, a severe pediatric encephalopathy. Many physiological effects of Scn1b deletion on CNS neurons have been described. In contrast, little is known about the role of Scn1b in peripheral neurons in vivo. Here we demonstrate that Scn1b null DRG neurons exhibit a depolarizing shift in the voltage dependence of TTX-S INa inactivation, reduced persistent TTX-R INa, a prolonged rate of recovery of TTX-R INa from inactivation, and reduced cell surface expression of Nav1.9 compared with their WT littermates. Investigation of action potential firing shows that Scn1b null DRG neurons are hyperexcitable compared with WT. Consistent with this, transient outward K+ current (Ito) is significantly reduced in null DRG neurons. We conclude that Scn1b regulates the electrical excitability of nociceptive DRG neurons in vivo by modulating both INa and IK. PMID:21555511

  16. Membrane Mechanics of Primary Afferent Neurons in the Dorsal Root Ganglia of Rats.

    Science.gov (United States)

    Kanda, Hirosato; Gu, Jianguo G

    2017-04-25

    Membrane mechanics is an important biological factor regulating many cellular functions including cell motility, intercellular and intracellular signaling, gene expression, and membrane ion channel activity. Primary afferent neurons transduce sensory information about temperature, touch, and pain. These sensory functions may be profoundly affected by the states of primary afferent neuron mechanics. However, membrane mechanics of primary afferent neurons is largely unknown. In this study, we established the optical trapping technique for determining membrane mechanics of cultured primary afferent neurons of the dorsal root ganglia (DRG). We further determined the roles of cytoskeleton and membrane lipids in DRG neuron mechanics. We found that DRG neurons had a plasma membrane tension of ∼54 pN/μm, and the tension was significantly decreased to ∼29 pN/μm by cytochalasin D treatment to disrupt actin cytoskeleton and increased to ∼79 pN/μm by methyl-β-cyclodextrin treatment to sequester membrane cholesterol. DRG neuron membrane stiffness was not significantly affected by the cytoskeleton disruption but was significantly increased after cholesterol sequestration. Our findings elucidate membrane mechanical properties of primary afferent neurons, which provide, to our knowledge, a new perspective on their sensory functions. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  17. Comparison of AAV serotypes for gene delivery to dorsal root ganglion neurons.

    Science.gov (United States)

    Mason, Matthew R J; Ehlert, Erich M E; Eggers, Ruben; Pool, Chris W; Hermening, Stephan; Huseinovic, Angelina; Timmermans, Eric; Blits, Bas; Verhaagen, Joost

    2010-04-01

    For many experiments in the study of the peripheral nervous system, it would be useful to genetically manipulate primary sensory neurons. We have compared vectors based on adeno-associated virus (AAV) serotypes 1, 2, 3, 4, 5, 6, and 8, and lentivirus (LV), all expressing green fluorescent protein (GFP), for efficiency of transduction of sensory neurons, expression level, cellular tropism, and persistence of transgene expression following direct injection into the dorsal root ganglia (DRG), using histological quantification and qPCR. Two weeks after injection, AAV1, AAV5, and AAV6 had transduced the most neurons. The time course of GFP expression from these three vectors was studied from 1 to 12 weeks after injection. AAV5 was the most effective serotype overall, followed by AAV1. Both these serotypes showed increasing neuronal transduction rates at later time points, with some injections of AAV5 yielding over 90% of DRG neurons GFP(+) at 12 weeks. AAV6 performed well initially, but transduction rates declined dramatically between 4 and 12 weeks. AAV1 and AAV5 both transduced large-diameter neurons, IB4(+) neurons, and CGRP(+) neurons. In conclusion, AAV5 is a highly effective gene therapy vector for primary sensory neurons following direct injection into the DRG.

  18. Multielectrode array recordings of bladder and perineal primary afferent activity from the sacral dorsal root ganglia

    Science.gov (United States)

    Bruns, Tim M.; Gaunt, Robert A.; Weber, Douglas J.

    2011-10-01

    The development of bladder and bowel neuroprostheses may benefit from the use of sensory feedback. We evaluated the use of high-density penetrating microelectrode arrays in sacral dorsal root ganglia (DRG) for recording bladder and perineal afferent activity. Arrays were inserted in S1 and S2 DRG in three anesthetized cats. Neural signals were recorded while the bladder volume was modulated and mechanical stimuli were applied to the perineal region. In two experiments, 48 units were observed that tracked bladder pressure with their firing rates (79% from S2). At least 50 additional units in each of the three experiments (274 total; 60% from S2) had a significant change in their firing rates during one or more perineal stimulation trials. This study shows the feasibility of obtaining bladder-state information and other feedback signals from the pelvic region with a sacral DRG electrode interface located in a single level. This natural source of feedback would be valuable for providing closed-loop control of bladder or other pelvic neuroprostheses.

  19. Plasticity of Select Primary Afferent Projections to the Dorsal Horn after a Lumbosacral Ventral Root Avulsion Injury and Root Replantation in Rats.

    Science.gov (United States)

    Bigbee, Allison J; Akhavan, Mahnaz; Havton, Leif A

    2017-01-01

    Injuries to the conus medullaris and cauda equina portions of the spinal cord result in neurological impairments, including paralysis, autonomic dysfunction, and pain. In experimental studies, earlier investigations have shown that a lumbosacral ventral root avulsion (VRA) injury results in allodynia, which may be ameliorated by surgical replantation of the avulsed ventral roots. Here, we investigated the long-term effects of an L6 + S1 VRA injury on the plasticity of three populations of afferent projections to the dorsal horn in rats. At 8 weeks after a unilateral L6 + S1 VRA injury, quantitative morphological studies of the adjacent L5 dorsal horn showed reduced immunoreactivity (IR) for the vesicular glutamate transporter, VGLUT1 and isolectin B4 (IB4) binding, whereas IR for calcitonin gene-related peptide (CGRP) was unchanged. The IR for VGLUT1 and CGRP as well as IB4 binding was at control levels in the L5 dorsal horn at 8 weeks following an acute surgical replantation of the avulsed L6 + S1 ventral roots. Quantitative morphological studies of the L5 dorsal root ganglia (DRGs) showed unchanged neuronal numbers for both the VRA and replanted series compared to shams. The portions of L5 DRG neurons expressing IR for VGLUT1 and CGRP, and IB4 binding were also the same between the VRA, replanted, and sham-operated groups. We conclude that the L5 dorsal horn shows selective plasticity for VGLUT1 and IB4 primary afferent projections after an L6 + S1 VRA injury and surgical repair.

  20. Plasticity of Select Primary Afferent Projections to the Dorsal Horn after a Lumbosacral Ventral Root Avulsion Injury and Root Replantation in Rats

    Directory of Open Access Journals (Sweden)

    Allison J. Bigbee

    2017-07-01

    Full Text Available Injuries to the conus medullaris and cauda equina portions of the spinal cord result in neurological impairments, including paralysis, autonomic dysfunction, and pain. In experimental studies, earlier investigations have shown that a lumbosacral ventral root avulsion (VRA injury results in allodynia, which may be ameliorated by surgical replantation of the avulsed ventral roots. Here, we investigated the long-term effects of an L6 + S1 VRA injury on the plasticity of three populations of afferent projections to the dorsal horn in rats. At 8 weeks after a unilateral L6 + S1 VRA injury, quantitative morphological studies of the adjacent L5 dorsal horn showed reduced immunoreactivity (IR for the vesicular glutamate transporter, VGLUT1 and isolectin B4 (IB4 binding, whereas IR for calcitonin gene-related peptide (CGRP was unchanged. The IR for VGLUT1 and CGRP as well as IB4 binding was at control levels in the L5 dorsal horn at 8 weeks following an acute surgical replantation of the avulsed L6 + S1 ventral roots. Quantitative morphological studies of the L5 dorsal root ganglia (DRGs showed unchanged neuronal numbers for both the VRA and replanted series compared to shams. The portions of L5 DRG neurons expressing IR for VGLUT1 and CGRP, and IB4 binding were also the same between the VRA, replanted, and sham-operated groups. We conclude that the L5 dorsal horn shows selective plasticity for VGLUT1 and IB4 primary afferent projections after an L6 + S1 VRA injury and surgical repair.

  1. Peripheral distribution of the human dorsal nerve of the penis.

    Science.gov (United States)

    Yang, C C; Bradley, W E

    1998-06-01

    The integrity of the dorsal nerve of the penis is crucial for normal erectile and ejaculatory function. To our knowledge a description of this nerve along the phallus has not been formally described. We illustrate the distribution of the dorsal nerve of the penis to the penile shaft, anterior urethra and glans. Neuroanatomical dissections were performed on 28 cadaver penis specimens. Electrodiagnostic testing was conducted on 10 healthy male subjects to confirm the anatomical findings. The dorsal nerve of the penis consists of 2 populations of axons, one to innervate the penile shaft and urethra, and the other to innervate the glans. Stimulation of the urethra resulted in responses recorded in the main trunk of the dorsal nerve of the penis and stimulation of the nerve evoked responses within the urethra. Bulbocavernosus muscle contraction was elicited following urethral stimulation. Urethral innervation by the dorsal nerve of the penis supports the view that urethral afferent impulses are a component of reflex ejaculatory activity. The pattern of glanular innervation by the dorsal nerve of the penis identifies the glans as a sensory end organ for sexual reflexes. The undulating character of the dorsal nerve of the penis is a mechanism by which the nerve can accommodate to significant changes in penile length with erection. Electrodiagnostic studies of the dorsal nerve of the penis should be modified to consider the anatomical findings.

  2. Sigma-1 receptor expression in the dorsal root ganglion: Reexamination using a highly specific antibody.

    Science.gov (United States)

    Mavlyutov, Timur A; Duellman, Tyler; Kim, Hung Tae; Epstein, Miles L; Leese, Charlotte; Davletov, Bazbek A; Yang, Jay

    2016-09-07

    Sigma-1 receptor (S1R) is a unique pluripotent modulator of living systems and has been reported to be associated with a number of neurological diseases including pathological pain. Intrathecal administration of S1R antagonists attenuates the pain behavior of rodents in both inflammatory and neuropathic pain models. However, the S1R localization in the spinal cord shows a selective ventral horn motor neuron distribution, suggesting the high likelihood of S1R in the dorsal root ganglion (DRG) mediating the pain relief by intrathecally administered drugs. Since primary afferents are the major component in the pain pathway, we examined the mouse and rat DRGs for the presence of the S1R. At both mRNA and protein levels, quantitative RT-PCR (qRT-PCR) and Western confirmed that the DRG contains greater S1R expression in comparison to spinal cord, cortex, or lung but less than liver. Using a custom-made highly specific antibody, we demonstrated the presence of a strong S1R immuno-fluorescence in all rat and mouse DRG neurons co-localizing with the Neuron-Specific Enolase (NSE) marker, but not in neural processes or GFAP-positive glial satellite cells. In addition, S1R was absent in afferent terminals in the skin and in the dorsal horn of the spinal cord. Using immuno-electron microscopy, we showed that S1R is detected in the nuclear envelope and endoplasmic reticulum (ER) of DRG cells. In contrast to other cells, S1R is also located directly at the plasma membrane of the DRG neurons. The presence of S1R in the nuclear envelope of all DRG neurons suggests an exciting potential role of S1R as a regulator of neuronal nuclear activities and/or gene expression, which may provide insight toward new molecular targets for modulating nociception at the level of primary afferent neurons. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Boundary cap neural crest stem cells homotopically implanted to the injured dorsal root transitional zone give rise to different types of neurons and glia in adult rodents

    OpenAIRE

    Trolle, Carl; Abrahamsson, Ninnie; König, Niclas; Vasylovska, Svitlana; Kozlova, Elena

    2014-01-01

    The boundary cap is a transient group of neural crest-derived cells located at the presumptive dorsal root transitional zone (DRTZ) when sensory axons enter the spinal cord during development. Later, these cells migrate to dorsal root ganglia and differentiate into subtypes of sensory neurons and glia. After birth when the DRTZ is established, sensory axons are no longer able to enter the spinal cord. Here we explored the fate of mouse bNCSCs implanted to the uninjured DRTZ after dorsal root ...

  4. Functional Properties and Toxin Pharmacology of a Dorsal Root Ganglion Sodium Channel Viewed through its Voltage Sensors

    OpenAIRE

    Bosmans, Frank; Puopolo, Michelino; Martin-Eauclaire, Marie-France; Swartz, Kenton J.; Bean, Bruce Palmer

    2011-01-01

    The voltage-activated sodium (Nav) channel Nav1.9 is expressed in dorsal root ganglion (DRG) neurons where it is believed to play an important role in nociception. Progress in revealing the functional properties and pharmacological sensitivities of this non-canonical Nav channel has been slow because attempts to express this channel in a heterologous expression system have been unsuccessful. Here, we use a protein engineering approach to dissect the contributions of the four Nav1.9 voltage se...

  5. [Experimental research on substance P content of hypothalamus and dorsal root ganglia in rats with lumbar vertebrae Gucuofeng model].

    Science.gov (United States)

    Chen, Bo; Lin, Xun; Pang, Jian; Kong, Ling-jun; Zhan, Hong-sheng; Cheng, Ying-wu; Shi, Yin-yu

    2015-01-01

    To detect the effects of lumbar vertebrae Gucuofeng on the substance P content of hypothalamus and dorsal root ganglia in rat models. A hundred and twenty SPF level SD male rats with the weight of 350 to 450 g were randomly divided into rotary fixation group (RF group), simple fixation group (SF group) and sham-operation group (Sham group). The external link fixation system was implanted into the L4-L6 of rats in RF group and SF group; and in RF group, that the L5 spinous process was rotated to the right resulted in L4, L5, L6 spinous process not collinear; in SF group, the external link fixation system was simply implanted and not rotated. The rats of Sham group were not implanted the external link fixation system and only open and suture. The substance P content of hypothalamus and dorsal root ganglia were detected at 1, 4, 8, 12 weeks after operation. Substance P content of hypothalamus in RF group and SF group was lower than Sham group at 1, 4, 8 weeks after operation (Phypothalamus among three groups at 12 weeks after operation (P>0.05). Lumbar vertebrae Gucuofeng can inhibit the analgesic activity of substance P in hypothalamus and promote the synthesis and transmission of substance P in dorsal root ganglia, so as to cause or aggravate the pain.

  6. Anatomical study on the relationship between the dorsal root ganglion and the intervertebral disc in the lumbar spine

    Directory of Open Access Journals (Sweden)

    Emiliano Vialle

    2015-08-01

    Full Text Available ABSTRACTOBJECTIVE: To describe the location of the dorsal root ganglion in relation to the intervertebral disc, including the "triangular" safety zone for minimally invasive surgery in the lumbar spine. METHODS: Eight adult cadavers were dissected bilaterally in the lumbar region, using a posterolateral approach, so as to expose the L3L4 and L4L5 spaces, thereby obtaining measurements relating to the space between the intervertebral disc, pedicles cranial and caudal to the disc, path of the nerve root, dorsal ganglion and safety triangle. RESULTS: The measurements obtained were constant, without significant differences between levels or any laterality. The dorsal ganglion occupied the lateral border of the triangular safety zone in all the specimens analyzed. CONCLUSION: Precise localization of the ganglion shows that the safety margin for minimally invasive procedures is less than what is presented in studies that only involve measurements of the nerve root, thus perhaps explaining the presence of neuropathic pain after some of these procedures.

  7. Chronic Compression of the Dorsal Root Ganglion Enhances Mechanically Evoked Pain Behavior and the Activity of Cutaneous Nociceptors in Mice.

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    Tao Wang

    Full Text Available Radicular pain in humans is usually caused by intraforaminal stenosis and other diseases affecting the spinal nerve, root, or dorsal root ganglion (DRG. Previous studies discovered that a chronic compression of the DRG (CCD induced mechanical allodynia in rats and mice, with enhanced excitability of DRG neurons. We investigated whether CCD altered the pain-like behavior and also the responses of cutaneous nociceptors with unmyelinated axons (C-fibers to a normally aversive punctate mechanical stimulus delivered to the hairy skin of the hind limb of the mouse. The incidence of a foot shaking evoked by indentation of the dorsum of foot with an aversive von Frey filament (tip diameter 200 μm, bending force 20 mN was significantly higher in the foot ipsilateral to the CCD surgery as compared to the contralateral side on post-operative days 2 to 8. Mechanically-evoked action potentials were electrophysiologically recorded from the L3 DRG, in vivo, from cell bodies visually identified as expressing a transgenically labeled fluorescent marker (neurons expressing either the receptor MrgprA3 or MrgprD. After CCD, 26.7% of MrgprA3+ and 32.1% MrgprD+ neurons exhibited spontaneous activity (SA, while none of the unoperated control neurons had SA. MrgprA3+ and MrgprD+ neurons in the compressed DRG exhibited, in comparison with neurons from unoperated control mice, an increased response to the punctate mechanical stimuli for each force applied (6, 20, 40, and 80 mN. We conclude that CCD produced both a behavioral hyperalgesia and an enhanced response of cutaneous C-nociceptors to aversive punctate mechanical stimuli.

  8. [EFFECT OF PEPTIDE SEMAX ON SYNAPTIC ACTIVITY AND SHORT-TERM PLASTICITY OF GLUTAMATERGIC SYNAPSES OF CO-CULTURED DORSAL ROOT GANGLION AND DORSAL HORN NEURONS].

    Science.gov (United States)

    Shypshyna, M S; Veselovsky, N S; Myasoedov, N F; Shram, S I; Fedulova, S A

    2015-01-01

    The influence of long-term culturing (12 days in vitro) of dorsal root ganglion (DRG) and dorsal horn (DH) neurons with peptide Semax on the level of synaptic activity at co-cultures, as well as short-term plasticity in sensory synapses were studied. It has been shown that neuronal culturing with peptide at concentrations of 10 and 100 µM led to increasing the frequency of spontaneous glutamatergic postsynaptic currents in DH neurons to 71.7 ± 1.8% and 93.9 ± 3.1% (n = 6; P effect on the amplitude and frequency of miniature glutamatergic currents, but causes an increase of the amplitudes of spontaneous postsynaptic currents, as well as elevates the quantum content. The data show the increase of multivesicular glutamate release efficiency in neural networks of co-cultures following incubation with the peptide. Also Semax (10 and 100 µM) induces changes of the basic parameters of short-term plasticity in sensory synapses: (1) increasing the paired-pulse ratio from 0.53 ± 0.028 (n = 8) to 0.91 ± 0.072 (n = 6, P effect of Semax on the activity of glutamatergic synapses in neural networks of co-cultures, as well as the ability of the peptide to effectively modulate the short-term plasticity in sensory synapses.

  9. Role of TRPM8 in dorsal root ganglion in nerve injury-induced chronic pain

    Directory of Open Access Journals (Sweden)

    Su Lin

    2011-11-01

    Full Text Available Abstract Background Chronic neuropathic pain is an intractable pain with few effective treatments. Moderate cold stimulation can relieve pain, and this may be a novel train of thought for exploring new methods of analgesia. Transient receptor potential melastatin 8 (TRPM8 ion channel has been proposed to be an important molecular sensor for cold. Here we investigate the role of TRPM8 in the mechanism of chronic neuropathic pain using a rat model of chronic constriction injury (CCI to the sciatic nerve. Results Mechanical allodynia, cold and thermal hyperalgesia of CCI rats began on the 4th day following surgery and maintained at the peak during the period from the 10th to 14th day after operation. The level of TRPM8 protein in L5 dorsal root ganglion (DRG ipsilateral to nerve injury was significantly increased on the 4th day after CCI, and reached the peak on the 10th day, and remained elevated on the 14th day following CCI. This time course of the alteration of TRPM8 expression was consistent with that of CCI-induced hyperalgesic response of the operated hind paw. Besides, activation of cold receptor TRPM8 of CCI rats by intrathecal application of menthol resulted in the inhibition of mechanical allodynia and thermal hyperalgesia and the enhancement of cold hyperalgesia. In contrast, downregulation of TRPM8 protein in ipsilateral L5 DRG of CCI rats by intrathecal TRPM8 antisense oligonucleotide attenuated cold hyperalgesia, but it had no effect on CCI-induced mechanical allodynia and thermal hyperalgesia. Conclusions TRPM8 may play different roles in mechanical allodynia, cold and thermal hyperalgesia that develop after nerve injury, and it is a very promising research direction for the development of new therapies for chronic neuroapthic pain.

  10. Citral Sensing by TRANSient Receptor Potential Channels in Dorsal Root Ganglion Neurons

    Science.gov (United States)

    Stotz, Stephanie C.; Vriens, Joris; Martyn, Derek; Clardy, Jon; Clapham, David E.

    2008-01-01

    Transient receptor potential (TRP) ion channels mediate key aspects of taste, smell, pain, temperature sensation, and pheromone detection. To deepen our understanding of TRP channel physiology, we require more diverse pharmacological tools. Citral, a bioactive component of lemongrass, is commonly used as a taste enhancer, as an odorant in perfumes, and as an insect repellent. Here we report that citral activates TRP channels found in sensory neurons (TRPV1 and TRPV3, TRPM8, and TRPA1), and produces long-lasting inhibition of TRPV1–3 and TRPM8, while transiently blocking TRPV4 and TRPA1. Sustained citral inhibition is independent of internal calcium concentration, but is state-dependent, developing only after TRP channel opening. Citral's actions as a partial agonist are not due to cysteine modification of the channels nor are they a consequence of citral's stereoisoforms. The isolated aldehyde and alcohol cis and trans enantiomers (neral, nerol, geranial, and geraniol) each reproduce citral's actions. In juvenile rat dorsal root ganglion neurons, prolonged citral inhibition of native TRPV1 channels enabled the separation of TRPV2 and TRPV3 currents. We find that TRPV2 and TRPV3 channels are present in a high proportion of these neurons (94% respond to 2-aminoethyldiphenyl borate), consistent with our immunolabeling experiments and previous in situ hybridization studies. The TRPV1 activation requires residues in transmembrane segments two through four of the voltage-sensor domain, a region previously implicated in capsaicin activation of TRPV1 and analogous menthol activation of TRPM8. Citral's broad spectrum and prolonged sensory inhibition may prove more useful than capsaicin for allodynia, itch, or other types of pain involving superficial sensory nerves and skin. PMID:18461159

  11. Dorsal Root Ganglion (DRG) Stimulation in the Treatment of Phantom Limb Pain (PLP).

    Science.gov (United States)

    Eldabe, Sam; Burger, Katja; Moser, Heinrich; Klase, Daniel; Schu, Stefan; Wahlstedt, Anders; Vanderick, Bernard; Francois, Eric; Kramer, Jeffery; Subbaroyan, Jeyakumar

    2015-10-01

    Phantom limb pain (PLP) is a neuropathic condition in which pain is perceived as arising from an amputated limb. PLP is distinct from, although associated with, pain in the residual limb and nonpainful phantom sensations of the missing limb. Its treatment is extremely challenging; pharmaceutical options, while commonly employed, may be insufficient or intolerable. Neuromodulatory interventions such as spinal cord stimulation have generated mixed results and may be limited by poor somatotopic specificity. It was theorized that dorsal root ganglion (DRG) neuromodulation may be more effective. Patients trialed a DRG neurostimulation system for their PLP and were subsequently implanted if results were positive. Retrospective chart review was completed, including pain ratings on a 100-mm visual analogue scale (VAS) and patient-reported outcomes. Across eight patients, the average baseline pain rating was 85.5 mm. At follow-up (mean of 14.4 months), pain was rated at 43.5 mm. Subjective ratings of quality of life and functional capacity improved. Some patients reduced or eliminated pain medications. Patients reported precise concordance of the paresthesia with painful regions, including in their phantom limbs; in one case, stimulation eliminated PLP as well as nonpainful phantom sensations. Three patients experienced a diminution of pain relief, despite good initial outcomes. DRG neuromodulation may be an effective tool in treating this pain etiology. Clinical outcomes in this report support recent converging evidence suggesting that the DRG may be the site of PLP generation and/or maintenance. Further research is warranted to elucidate mechanisms and optimal treatment pathways. © 2015 International Neuromodulation Society.

  12. Trinitrobenzenesulphonic acid colitis alters Na 1.8 channel expression in mouse dorsal root ganglia neurons.

    Science.gov (United States)

    King, D E; Macleod, R J; Vanner, S J

    2009-08-01

    Visceral inflammation evokes hyperexcitability in nociceptive dorsal root ganglia (DRG) neurons and these changes are associated with increased voltage-gated sodium channel (Na(v)) 1.8 current density, but the molecular determinants of these changes are unclear. This study used Western blotting to measure changes in Na(v) 1.7, 1.8 and 1.9 protein expression during trinitrobenzenesulphonic acid (TNBS) colitis and quantitative polymerase chain reaction (PCR) to examine corresponding changes in mRNA. Colonic neurons were labelled with the retrograde tracer Fast Blue injected into the wall of the distal colon and quantitative PCR performed on laser-captured labelled colonic neurons from ganglia at T9-13 or unlabelled DRG neurons from the upper spinal cord. Immunohistochemistry and western blots were performed on whole DRG from the same sites. Fast Blue-labelled neurons demonstrated Na(v) 1.7, 1.8 and 1.9 immunoreactivity. On day 7 of colitis, which correlated with electrophysiological studies, there was a threefold increase in Na(v) 1.8 protein in ganglia from T9 to 13, but Na(v) 1.7 and 1.9 levels were unchanged. There was no corresponding change in the Na(v) 1.8 alpha-subunit mRNA levels. However, on days 2 and 4, Na(v) 1.8 mRNA was decreased 10-fold. Na(v) 1.8 protein and mRNA levels were unchanged in neurons isolated from ganglia in the upper spinal cord, where colonic neurons are not found. These findings suggest that the TNBS evoked increase in Na(v) 1.8 currents is associated with increased numbers of channels. The absence of corresponding changes in transcript suggests a translational or post-translational mechanism, but the 10-fold recovery of transcript preceding this time point also demonstrates a complex transcriptional regulation.

  13. Sources of axonal calcium loading during in vitro ischemia of rat dorsal roots.

    Science.gov (United States)

    Petrescu, Nicolae; Micu, Ileana; Malek, Sameh; Ouardouz, Mohamed; Stys, Peter K

    2007-04-01

    A detailed understanding of injury mechanisms in peripheral nerve fibers will help guide successful design of therapies for peripheral neuropathies. This study was therefore undertaken to examine the ionic mechanisms of Ca2+ overload in peripheral myelinated fibers subjected to chemical inhibition of energy metabolism. Myelinated axons from rat dorsal roots were co-loaded with Ca2+-sensitive (Oregon Green BAPTA-1) and Ca2+-insensitive (Alexa Fluor 594) dextran-conjugated fluorophores and imaged using confocal laser scanning microscopy. Axoplasmic regions were clearly outlined by the Ca2+-insensitive dye, from which axonal Ca2+-dependent fluorescence changes (FCa.ax) were measured. Block of Na+-K+ ATPase (ouabain), opening of Na+ channels (veratridine), and inhibiting energy metabolism (iodoacetate + NaN3) caused a rapid rise in FCa.ax to 96% above control after 30 min. Chemical ischemia (iodoacetate + NaN3) caused a more gradual increase in FCa.ax (54%), which was almost completely dependent on bath Ca2+, indicating that most of the Ca2+ accumulation occurred via influx across the axolemma. Na+ channel block (tetrodotoxin) reduced ischemic FCa.ax rise (14%); however, inhibition of L-type Ca2+ channels (nimodipine) had no effect (60%). In contrast, Na+-Ca2+ exchange inhibition (KB-R7943) significantly reduced ischemic FCa.ax rise (18%). Together our results indicate that the bulk of Ca2+ overload in injured peripheral myelinated axons occurs via reverse Na+-Ca2+ exchange, driven by axonal Na+ accumulation through voltage-gated tetrodotoxin-sensitive Na+ channels. This mechanism may represent a viable therapeutic target for peripheral neuropathies.

  14. Activation of neurokinin-1 receptors increases the excitability of guinea pig dorsal root ganglion cells.

    Science.gov (United States)

    Zhang, Xiulin; Pietra, Claudio; Lovati, Emanuela; de Groat, William C

    2012-10-01

    The suppression of overactive bladder symptoms in patients and overactive bladder reflexes in animal models by neurokinin (NK)-1 receptor antagonists raises the possibility that these drugs target sensory neurons. This mechanism was evaluated by examining the interactions between a specific NK-1 agonist, [Sar(9),Met(O(2))(11)]-substance P (Sar-Met-SP), and a potent NK-1 antagonist, netupitant (NTP), on small size (20-30 μm) dissociated L6 and S1 dorsal root ganglion (DRG) neurons from female guinea pigs. Current-clamp recording revealed that Sar-Met-SP (1 μM) elicited membrane depolarization (average 8.05 ± 1.38 mV) in 27% (18 of 65) of DRG neurons. In 74% of the remaining neurons (35 of 47) Sar-Met-SP decreased the rheobase for action potential (AP) generation and increased the response to a suprathreshold stimulus (3 times rheobase) without changing the membrane potential. Sar-Met-SP also induced changes in the action potential (AP) wave form, including 1) an increase in overshoot (average 5 mV, n = 35 neurons), 2) a prolongation of AP duration (from 4.64 to 5.29 ms, n = 34), and 3) a reduction in the maximal rate of AP repolarization. NTP (200 nM) reversed the Sar-Met-SP-induced changes. Ca(2+) imaging showed that application of Sar-Met-SP (1 μM) decreased the tachyphylaxis induced by repeated application of capsaicin (0.5 μM), an effect blocked by pretreatment with NTP (200 nM). These results raise the possibility that activation of NK-1 receptors in primary sensory neurons plays a role in the generation of overactive bladder and that block of NK-1 receptors in these neurons may contribute to efficacy of NK-1 antagonists in the treatment of overactive bladder symptoms.

  15. Citral sensing by Transient [corrected] receptor potential channels in dorsal root ganglion neurons.

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    Stephanie C Stotz

    2008-05-01

    Full Text Available Transient receptor potential (TRP ion channels mediate key aspects of taste, smell, pain, temperature sensation, and pheromone detection. To deepen our understanding of TRP channel physiology, we require more diverse pharmacological tools. Citral, a bioactive component of lemongrass, is commonly used as a taste enhancer, as an odorant in perfumes, and as an insect repellent. Here we report that citral activates TRP channels found in sensory neurons (TRPV1 and TRPV3, TRPM8, and TRPA1, and produces long-lasting inhibition of TRPV1-3 and TRPM8, while transiently blocking TRPV4 and TRPA1. Sustained citral inhibition is independent of internal calcium concentration, but is state-dependent, developing only after TRP channel opening. Citral's actions as a partial agonist are not due to cysteine modification of the channels nor are they a consequence of citral's stereoisoforms. The isolated aldehyde and alcohol cis and trans enantiomers (neral, nerol, geranial, and geraniol each reproduce citral's actions. In juvenile rat dorsal root ganglion neurons, prolonged citral inhibition of native TRPV1 channels enabled the separation of TRPV2 and TRPV3 currents. We find that TRPV2 and TRPV3 channels are present in a high proportion of these neurons (94% respond to 2-aminoethyldiphenyl borate, consistent with our immunolabeling experiments and previous in situ hybridization studies. The TRPV1 activation requires residues in transmembrane segments two through four of the voltage-sensor domain, a region previously implicated in capsaicin activation of TRPV1 and analogous menthol activation of TRPM8. Citral's broad spectrum and prolonged sensory inhibition may prove more useful than capsaicin for allodynia, itch, or other types of pain involving superficial sensory nerves and skin.

  16. The dorsal root ganglion in chronic pain and as a target for neuromodulation: a review.

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    Krames, Elliot S

    2015-01-01

    In the not-too-distant past, the dorsal root ganglion (DRG) was portrayed as a passive neural structure without involvement in the development or maintenance of chronic neuropathic pain (NP). The DRG was thought of as a structure that merely "supported" physiologic communication between the peripheral nervous system (PNS) and the central nervous system (CNS). Newer scientific information regarding the anatomic and physiologic changes that occur within the DRG as a result of environmental pressures has dispelled this concept and suggests that the DRG is an active participant in the development of NP. This new information, along with new clinical data showing that stimulation of the DRG reduces intensity of pain, suggests that the DRG can be a robust target for neuromodulation therapies. A review of the anatomical and physiological literature regarding the role of the DRG in the development of NP was performed utilizing SciBase, PubMed, and Google Scholar. The information gathered was used to lay an anatomic and physiologic foundation for establishing the DRG as a relevant target for neuromodulation therapies and to formulate a hypothesis as to how electrical stimulation of the DRG might reverse the process and perception of NP. The DRG is an active participant in the development of NP. DRG stimulation has multiple effects on the abnormal changes that occur within the DRG as a result of peripheral afferent fiber injury. The sum total of these stimulation effects is to stabilize and decrease hyperexcitability of DRG neurons and thereby decrease NP. © 2014 International Neuromodulation Society.

  17. Isolated dorsal root ganglion neurones inhibit receptor-dependent adenylyl cyclase activity in associated glial cells

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    Ng, KY; Yeung, BHS; Wong, YH; Wise, H

    2013-01-01

    Background and Purpose Hyper-nociceptive PGE2 EP4 receptors and prostacyclin (IP) receptors are present in adult rat dorsal root ganglion (DRG) neurones and glial cells in culture. The present study has investigated the cell-specific expression of two other Gs-protein coupled hyper-nociceptive receptor systems: β-adrenoceptors and calcitonin gene-related peptide (CGRP) receptors in isolated DRG cells and has examined the influence of neurone–glial cell interactions in regulating adenylyl cyclase (AC) activity. Experimental Approach Agonist-stimulated AC activity was determined in mixed DRG cell cultures from adult rats and compared with activity in DRG neurone-enriched cell cultures and pure DRG glial cell cultures. Key Results Pharmacological analysis showed the presence of Gs-coupled β2-adrenoceptors and CGRP receptors, but not β1-adrenoceptors, in all three DRG cell preparations. Agonist-stimulated AC activity was weakest in DRG neurone-enriched cell cultures. DRG neurones inhibited IP receptor-stimulated glial cell AC activity by a process dependent on both cell–cell contact and neurone-derived soluble factors, but this is unlikely to involve purine or glutamine receptor activation. Conclusions and Implications Gs-coupled hyper-nociceptive receptors are readily expressed on DRG glial cells in isolated cell cultures and the activity of CGRP, EP4 and IP receptors, but not β2-adrenoceptors, in glial cells is inhibited by DRG neurones. Studies using isolated DRG cells should be aware that hyper-nociceptive ligands may stimulate receptors on glial cells in addition to neurones, and that variable numbers of neurones and glial cells will influence absolute measures of AC activity and affect downstream functional responses. PMID:22924655

  18. Enrichment and proteomic analysis of plasma membrane from rat dorsal root ganglions

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    Lin Yong

    2009-11-01

    Full Text Available Abstract Background Dorsal root ganglion (DRG neurons are primary sensory neurons that conduct neuronal impulses related to pain, touch and temperature senses. Plasma membrane (PM of DRG cells plays important roles in their functions. PM proteins are main performers of the functions. However, mainly due to the very low amount of DRG that leads to the difficulties in PM sample collection, few proteomic analyses on the PM have been reported and it is a subject that demands further investigation. Results By using aqueous polymer two-phase partition in combination with high salt and high pH washing, PMs were efficiently enriched, demonstrated by western blot analysis. A total of 954 non-redundant proteins were identified from the plasma membrane-enriched preparation with CapLC-MS/MS analysis subsequent to protein separation by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE or shotgun digestion. 205 (21.5% of the identified proteins were unambiguously assigned as PM proteins, including a large number of signal proteins, receptors, ion channel and transporters. Conclusion The aqueous polymer two-phase partition is a simple, rapid and relatively inexpensive method. It is well suitable for the purification of PMs from small amount of tissues. Therefore, it is reasonable for the DRG PM to be enriched by using aqueous two-phase partition as a preferred method. Proteomic analysis showed that DRG PM was rich in proteins involved in the fundamental biological processes including material exchange, energy transformation and information transmission, etc. These data would help to our further understanding of the fundamental DRG functions.

  19. Cannabinoids inhibit acid-sensing ion channel currents in rat dorsal root ganglion neurons.

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    Yu-Qiang Liu

    Full Text Available Local acidosis has been found in various pain-generating conditions such as inflammation and tissue injury. Cannabinoids exert a powerful inhibitory control over pain initiation via peripheral cognate receptors. However, the peripheral molecular targets responsible for the antinociceptive effects of cannabinoids are still poorly understood. Here, we have found that WIN55,212-2, a cannabinoid receptor agonist, inhibits the activity of native acid-sensing ion channels (ASICs in rat dorsal root ganglion (DRG neurons. WIN55,212-2 dose-dependently inhibited proton-gated currents mediated by ASICs. WIN55,212-2 shifted the proton concentration-response curve downwards, with an decrease of 48.6±3.7% in the maximum current response but with no significant change in the EC(50 value. The inhibition of proton-gated current induced by WIN55,212-2 was almost completely blocked by the selective CB1 receptor antagonist AM 281, but not by the CB2 receptor antagonist AM630. Pretreatment of forskolin, an AC activator, and the addition of cAMP also reversed the inhibition of WIN55,212-2. Moreover, WIN55,212-2 altered acid-evoked excitability of rat DRG neurons and decreased the number of action potentials induced by acid stimuli. Finally, WIN55,212-2 attenuated nociceptive responses to injection of acetic acid in rats. These results suggest that WIN55,212-2 inhibits the activity of ASICs via CB1 receptor and cAMP dependent pathway in rat primary sensory neurons. Thus, cannabinoids can exert their analgesic action by interaction with ASICs in the primary afferent neurons, which was novel analgesic mechanism of cannabinoids.

  20. Impaired axonal regeneration by isolectin B4-binding dorsal root ganglion neurons in vitro.

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    Leclere, Pascal G; Norman, Emma; Groutsi, Filitsa; Coffin, Robert; Mayer, Ulrike; Pizzey, John; Tonge, David

    2007-01-31

    The subpopulation of dorsal root ganglion (DRG) neurons recognized by Griffonia simplicifolia isolectin B4 (IB4) differ from other neurons by expressing receptors for glial cell line-derived neurotrophic factor (GDNF) rather than neurotrophins. Additionally, IB4-labeled neurons do not express the laminin receptor, alpha7-integrin (Gardiner et al., 2005), necessary for optimal axonal regeneration in the peripheral nervous system. In cultures of dissociated DRG neurons of adult mice on laminin, robust spontaneous neurite outgrowth from IB4-negative neurons occurs and is strongly enhanced by previous axotomy. In contrast, IB4-labeled neurons show little neurite outgrowth and do not express GAP 43, even after axotomy or culture with GDNF. Moreover, growth of their axons through collagen gels is impaired compared with other DRG neurons. To determine whether the sparse neurite outgrowth of IB4-labeled neurons is attributable to lack of integrin expression, DRG cultures were infected with a herpes simplex 1 vector encoding alpha7-integrin, but its forced expression failed to promote neurite outgrowth in either IB4-labeled or other DRG neurons or in cultured adult retinal ganglion cells. Forced coexpression of both alpha7-integrin and GAP 43 also failed to promote neurite outgrowth in IB4-labeled neurons. In addition, cultured sciatic nerve segments were found to release much lower levels of GDNF, demonstrated by ELISA, than nerve growth factor. These findings together with their impaired intrinsic axonal regeneration capacity may contribute to the known vulnerability of the IB4-labeled population of DRG neurons to peripheral nerve injury.

  1. Single-cell analysis of sodium channel expression in dorsal root ganglion neurons.

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    Ho, Cojen; O'Leary, Michael E

    2011-01-01

    Sensory neurons of the dorsal root ganglia (DRG) express multiple voltage-gated sodium (Na) channels that substantially differ in gating kinetics and pharmacology. Small-diameter (30 μm) predominately express fast TTX-S Na current. Na channel expression was further investigated using single-cell RT-PCR to measure the transcripts present in individually harvested DRG neurons. Consistent with cellular electrophysiology, the small neurons expressed transcripts encoding for both TTX-S (Nav1.1, Nav1.2, Nav1.6, and Nav1.7) and TTX-R (Nav1.8 and Nav1.9) Na channels. Nav1.7, Nav1.8 and Nav1.9 were the predominant Na channels expressed in the small neurons. The large neurons highly expressed TTX-S isoforms (Nav1.1, Nav1.6, and Nav1.7) while TTX-R channels were present at comparatively low levels. A unique subpopulation of the large neurons was identified that expressed TTX-R Na current and high levels of Nav1.8 transcript. DRG neurons also displayed substantial differences in the expression of neurofilaments (NF200, peripherin) and Necl-1, a neuronal adhesion molecule involved in myelination. The preferential expression of NF200 and Necl-1 suggests that large-diameter neurons give rise to thick myelinated axons. Small-diameter neurons expressed peripherin, but reduced levels of NF200 and Necl-1, a pattern more consistent with thin unmyelinated axons. Single-cell analysis of Na channel transcripts indicates that TTX-S and TTX-R Na channels are differentially expressed in large myelinated (Nav1.1, Nav1.6, and Nav1.7) and small unmyelinated (Nav1.7, Nav1.8, and Nav1.9) sensory neurons. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. Propofol up-regulates Mas receptor expression in dorsal root ganglion neurons.

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    Cao, Lijun; Xun, Junmei; Jiang, Xinghua; Tan, Rong

    2013-08-01

    Mas is a functional binding site for angiotensin (Ang)-(1-7), a critical component of the renin-angiotensin system that is involved in processing nociceptive information. A recent study reported the localization of Mas in rat dorsal root ganglia (DRG) and demonstrated that Ang-(1-7) produced a dose-dependent peripheral antinociceptive effect in rats through the Mas receptor by an opioid-independent mechanism. In the present study, we for the first time examined the effect of propofol on Mas expression in cultured DRG neurons. We treated rat DRG neurons with propofol at different concentrations (0.1, 0.5, 1, 5 or 10 microM) for different length of time (0.5, 1, 2, 4 or 6 h) with or without transcription inhibitor actinomycin D or different kinase inhibitors. Propofol increased the Mas receptormRNA level in a statistically significant dose- and time-dependent manner within 4 h, which led to dose-dependent up-regulation of the Mas receptor protein level as well as Ang-(1-7) binding on the cell membrane. Actinomycin D (1 mg/ml) and p38 mitogen-activated protein kinase inhibitor PD169316 (25 microM) completely abolished the effect of propofol on Mas receptor expression in DRG neurons. In conclusion, we demonstrate that propofol markedly up-regulates Mas receptor expression at the transcription level in DRG neurons by a p38 MAPK-dependent mechanism. This study provides new insights into the mechanisms of action of propofol in peripheral antinociception, and suggests a new regulatory mechanism on the Ang-(1-7)/Mas axis in the peripheral nervous system.

  3. Chronic nerve injury-induced Mas receptor expression in dorsal root ganglion neurons alleviates neuropathic pain.

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    Zhao, Yuanting; Qin, Yue; Liu, Tuanjiang; Hao, Dingjun

    2015-12-01

    Neuropathic pain, which is characterized by hyperalgesia, allodynia and spontaneous pain, is one of the most painful symptoms that can be experienced in the clinic. It often occurs as a result of injury to the peripheral nerves, dorsal root ganglion (DRG), spinal cord or brain. The renin-angiotensin system (RAS) plays an important role in nociception. As an essential component of the RAS, the angiotensin (Ang)-(1-7)/Mas axis may be involved in antinociception. The aim of the present study was to explore the expression pattern of Mas in DRG neurons following chronic nerve injury and examine the effects of Mas inhibition and activation on neuropathic pain in a chronic constriction injury (CCI) rat model. The results showed, that compared with the sham group, CCI caused a time-dependent induction of Mas expression at both the mRNA and the protein levels in DRG neurons. Consistent with the results, isolated DRG neurons showed a time-dependent increase in Ang-(1-7) binding on the cell membrane following the CCI surgery, but not the sham surgery. Compared with the sham control groups, CCI significantly decreased the paw withdrawal latency and threshold, and this was markedly improved and aggravated by intrathecal injection of the selective Mas agonist Ang-(1-7) and the selective Mas inhibitor D-Pro7-Ang-(1-7), respectively. In conclusion, this study has provided the first evidence, to the best of our knowledge, that the Mas expression in DRG neurons is time-dependently induced by chronic nerve injury and that the intrathecal activation and inhibition of Mas can improve and aggravate CCI-induced neuropathic pain, respectively. This study has provided novel insights into the pathophysiological process of neuropathic pain and suggests that the Ang-(1-7)/Mas axis could be an effective therapeutic target for neuropathic pain, warranting further study.

  4. Assessing the effectiveness of ‘pulse radiofrequency treatment of dorsal root ganglion’ in patients with chronic lumbar radicular pain: study protocol for a randomized control trial

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    Shanthanna Harsha

    2012-04-01

    Full Text Available Abstract Background Chronic lumbar radicular pain can be described as neuropathic pain along the distribution of a particular nerve root. The dorsal root ganglion has been implicated in its pathogenesis by giving rise to abnormal impulse generation as a result of irritation, direct compression and sensitization. Chronic lumbar radicular pain is commonly treated with medications, physiotherapy and epidural steroid injections. Epidural steroid injections are associated with several common and rarer side effects such as spinal cord infarction and death. It is essential and advantageous to look for alternate interventions which could be effective with fewer side effects. Pulse radio frequency is a relatively new technique and is less destructive then conventional radiofrequency. Safety and effectiveness of pulse radio frequency in neuropathic pain has been demonstrated in animal and humans studies. Although its effects on dorsal root ganglion have been studied in animals there is only one randomized control trial in literature demonstrating its effectiveness in cervical radicular pain and none in lumbar radicular pain. Our primary objective is to study the feasibility of a larger trial in terms of recruitment and methodology. Secondary objectives are to compare the treatment effects and side effects. Methods/designs This is a single-center, parallel, placebo-controlled, triple-blinded (patients, care-givers, and outcome assessors, randomized control trial. Participants will have a history of chronic lumbar radicular pain for at least 4 months in duration. Once randomized, all patients will have an intervention involving fluoroscopy guided needle placement to appropriate dorsal root ganglion. After test stimulation in both groups; the study group will have a pulse radio frequency treatment at 42°C for 120 s to the dorsal root ganglion, with the control group having only low intensity test stimulation for the same duration. Primary outcome is to

  5. Dorsal root ganglia hypertrophy as in vivo correlate of oxaliplatin-induced polyneuropathy.

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    Leonidas Apostolidis

    Full Text Available To investigate in vivo morphological and functional correlates of oxaliplatin-induced peripheral neuropathy (OXA-PNP by magnetic resonance neurography (MRN.Twenty patients (7 female, 13 male, 58.9±10.0 years with mild to moderate OXA-PNP and 20 matched controls (8 female, 12 male, 55.7±15.6 years were prospectively enrolled. All patients underwent a detailed neurophysiological examination prior to neuroimaging. A standardized imaging protocol at 3.0 Tesla included the lumbosacral plexus and both sciatic nerves and their branches using T2-weighted fat-saturated sequences and diffusion tensor imaging. Quantitative assessment included volumetry of the dorsal root ganglia (DRG, sciatic nerve normalized T2 (nT2 signal and caliber, and fractional anisotropy (FA, mean diffusivity (MD, axial (AD and radial diffusivity (RD. Additional qualitative evaluation of sciatic, peroneal, and tibial nerves evaluated the presence, degree, and distribution of nerve lesions.DRG hypertrophy in OXA-PNP patients (207.3±47.7mm3 vs. 153.0±47.1mm3 in controls, p = 0.001 was found as significant morphological correlate of the sensory neuronopathy. In contrast, peripheral nerves only exhibited minor morphological alterations qualitatively. Quantitatively, sciatic nerve caliber (27.3±6.7mm2 vs. 27.4±7.4mm2, p = 0.80 and nT2 signal were not significantly changed in patients (1.32±0.22 vs. 1.22±0.26, p = 0.16. AD, RD, and MD showed a non-significant decrease in patients, while FA was unchanged.OXA-PNP manifests with morphological and functional correlates that can be detected in vivo by MRN. We report hypertrophy of the DRG that stands in contrast to experimental and postmortem studies. DRG volume should be further investigated as a biomarker in other sensory peripheral neuropathies and ganglionopathies.

  6. Chronic recruitment of primary afferent neurons by microstimulation in the feline dorsal root ganglia

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    Fisher, Lee E.; Ayers, Christopher A.; Ciollaro, Mattia; Ventura, Valérie; Weber, Douglas J.; Gaunt, Robert A.

    2014-06-01

    Objective. This study describes results of primary afferent neural microstimulation experiments using microelectrode arrays implanted chronically in the lumbar dorsal root ganglia (DRG) of four cats. The goal was to test the stability and selectivity of these microelectrode arrays as a potential interface for restoration of somatosensory feedback after damage to the nervous system such as amputation. Approach. A five-contact nerve-cuff electrode implanted on the sciatic nerve was used to record the antidromic compound action potential response to DRG microstimulation (2-15 µA biphasic pulses, 200 µs cathodal pulse width), and the threshold for eliciting a response was tracked over time. Recorded responses were segregated based on conduction velocity to determine thresholds for recruiting Group I and Group II/Aβ primary afferent fibers. Main results. Thresholds were initially low (5.1 ± 2.3 µA for Group I and 6.3 ± 2.0 µA for Group II/Aβ) and increased over time. Additionally the number of electrodes with thresholds less than or equal to 15 µA decreased over time. Approximately 12% of tested electrodes continued to elicit responses at 15 µA up to 26 weeks after implantation. Higher stimulation intensities (up to 30 µA) were tested in one cat at 23 weeks post-implantation yielding responses on over 20 additional electrodes. Within the first six weeks after implantation, approximately equal numbers of electrodes elicited only Group I or Group II/Aβ responses at threshold, but the relative proportion of Group II/Aβ responses decreased over time. Significance. These results suggest that it is possible to activate Group I or Group II/Aβ primary afferent fibers in isolation with penetrating microelectrode arrays implanted in the DRG, and that those responses can be elicited up to 26 weeks after implantation, although it may be difficult to achieve a consistent response day-to-day with currently available electrode technology. The DRG are compelling targets

  7. Motoneuron development influences dorsal root ganglia survival and Schwann cell development in a vertebrate model of spinal muscular atrophy.

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    Hao, Le Thi; Duy, Phan Q; Jontes, James D; Beattie, Christine E

    2015-01-15

    Low levels of the survival motor neuron protein (SMN) cause the disease spinal muscular atrophy. A primary characteristic of this disease is motoneuron dysfunction and paralysis. Understanding why motoneurons are affected by low levels of SMN will lend insight into this disease and to motoneuron biology in general. Motoneurons in zebrafish smn mutants develop abnormally; however, it is unclear where Smn is needed for motoneuron development since it is a ubiquitously expressed protein. We have addressed this issue by expressing human SMN in motoneurons in zebrafish maternal-zygotic (mz) smn mutants. First, we demonstrate that SMN is present in axons, but only during the period of robust motor axon outgrowth. We also conclusively demonstrate that SMN acts cell autonomously in motoneurons for proper motoneuron development. This includes the formation of both axonal and dendritic branches. Analysis of the peripheral nervous system revealed that Schwann cells and dorsal root ganglia (DRG) neurons developed abnormally in mz-smn mutants. Schwann cells did not wrap axons tightly and had expanded nodes of Ranvier. The majority of DRG neurons had abnormally short peripheral axons and later many of them failed to divide and died. Expressing SMN just in motoneurons rescued both of these cell types showing that their failure to develop was secondary to the developmental defects in motoneurons. Driving SMN just in motoneurons did not increase survival of the animal, suggesting that SMN is needed for motoneuron development and motor circuitry, but that SMN in other cells types factors into survival. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Photobiomodulation of the dorsal root ganglion for the treatment of low back pain: A pilot study.

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    Holanda, Vanessa Milanesi; Chavantes, Maria Cristina; Silva, Daniela Fatima Teixeira; de Holanda, Carlos Vanderlei M; de Oliveira, José Oswaldo; Wu, Xingjia; Anders, Juanita J

    2016-09-01

    Chronic low back pain is a worldwide public health issue with high socioeconomic impact. The aim of this study was to determine the efficacy of laser irradiation of the dorsal root ganglion of the second lumbar spinal nerve for chronic axial low back pain compared to lidocaine injection and radiofrequency treatment. Twenty-eight patients were randomly divided into three treatment groups: lidocaine injection, radiofrequency, or laser. The second intervertebral foramen between the second and third lumbar vertebrae was accessed by percutaneous needle puncture bilaterally, guided by fluoroscopy. In the local anesthetic group, injection of 1 ml lidocaine without epinephrine was applied through a 20-gauge (G20) Quincke tip spinal needle inserted in the second lumbar intervertebral foramen. In the radiofrequency group, the probe (150 mm long with a 5 mm active tip) was directed through a G20 needle placed in the second lumbar intervertebral foramen and neuromodulation was done with a radiofrequency of Cosman G4® in pulses of 20 ms with wash-out period of 480 ms, for 300 seconds at 42°C. A single treatment was used. In the laser treatment group, a continuous wave, 808 nm wavelength diode laser (Photon Lase III® DCM, Brazil), with an output power of 100 mW was used for a single treatment. An 18 gauge needle was placed in the second lumbar intervertebral foramen guided by fluoroscopy. Light was delivered through a 600 µm optical fiber placed in the G18 needle. The tip of the fiber extended 5 mm beyond the tip of the needle in the second lumbar intervertebral foramen. The beam spot size was 0.003 cm(2) , irradiance = 35W/cm(2) , exposure time = 84 seconds, energy density = 2800J/cm(2) , total energy was 8.4 J. The low back pain score was assessed by the visual analog scale (VAS) and Pain Relief Scale (PRS) pre, post procedure and in 1 month follow up. Temperature was measured using a digital thermometer. All patients in the local

  9. S3 Dorsal Root Ganglion/Nerve Root Stimulation for Refractory Postsurgical Perineal Pain: Technical Aspects of Anchorless Sacral Transforaminal Lead Placement

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    X. Zuidema

    2016-01-01

    Full Text Available Chronic perineal pain limits patients in physical and sexual activities, leading to social and psychological distress. In most cases, this pain develops after surgery in the urogenital area or as a consequence of trauma. Neuromodulation is one of the options in chronic postsurgical perineal pain treatment. We present a case of refractory perineal pain after right sided surgical resection of a Bartholin’s cyst which was treated with third sacral nerve root/dorsal root ganglion stimulation using the transforaminal approach. We describe a new anchorless lead placement technique using a unique curved lead delivery sheath. We postulate that this new posterior foraminal technique of lead placement is simple, safe, and reversible and may lower the occurrence of lead related complications.

  10. Inhibition of tetrodotoxin-resistant sodium current in dorsal root ganglia neurons mediated by D1/D5 dopamine receptors.

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    Galbavy, William; Safaie, Elham; Rebecchi, Mario J; Puopolo, Michelino

    2013-11-28

    Dopaminergic fibers originating from area A11 of the hypothalamus project to different levels of the spinal cord and represent the major source of dopamine. In addition, tyrosine hydroxylase, the rate-limiting enzyme for the synthesis of catecholamines, is expressed in 8-10% of dorsal root ganglia (DRG) neurons, suggesting that dopamine may be released in the dorsal root ganglia. Dopamine has been shown to modulate calcium current in DRG neurons, but the effects of dopamine on sodium current and on the firing properties of small DRG neurons are poorly understood. The effects of dopamine and dopamine receptor agonists were tested on the tetrodotoxin-resistant (TTX-R) sodium current recorded from acutely dissociated small (diameter ≤ 25 μm) DRG neurons. Dopamine (20 μM) and SKF 81297 (10 μM) caused inhibition of TTX-R sodium current in small DRG neurons by 23% and 37%, respectively. In contrast, quinpirole (20 μM) had no effects on the TTX-R sodium current. Inhibition by SKF 81297 of the TTX-R sodium current was not affected when the protein kinase A (PKA) activity was blocked with the PKA inhibitory peptide (6-22), but was greatly reduced when the protein kinase C (PKC) activity was blocked with the PKC inhibitory peptide (19-36), suggesting that activation of D1/D5 dopamine receptors is linked to PKC activity. Expression of D1and D5 dopamine receptors in small DRG neurons, but not D2 dopamine receptors, was confirmed by Western blotting and immunofluorescence analysis. In current clamp experiments, the number of action potentials elicited in small DRG neurons by current injection was reduced by ~ 30% by SKF 81297. We conclude that activation of D1/D5 dopamine receptors inhibits TTX-R sodium current in unmyelinated nociceptive neurons and dampens their intrinsic excitability by reducing the number of action potentials in response to stimulus. Increasing or decreasing levels of dopamine in the dorsal root ganglia may serve to adjust the sensitivity of

  11. CT-guided injection of a TRPV1 agonist around dorsal root ganglia decreases pain transmission in swine

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    Brown, Jacob D.; Saeed, Maythem; Do, Loi; Braz, Joao; Basbaum, Allan I.; Iadarola, Michael J.; Wilson, David M.; Dillon, William P.

    2016-01-01

    One approach to analgesia is to block pain at the site of origin or along the peripheral pathway by selectively ablating pain-transmitting neurons or nerve terminals directly. The heat/capsaicin receptor (TRPV1) expressed by nociceptive neurons is a compelling target for selective interventional analgesia because it leaves somatosensory and proprioceptive neurons intact. Resiniferatoxin (RTX), like capsaicin, is a TRPV1 agonist but has greater potency. We combine RTX-mediated inactivation with the precision of computed tomography (CT)–guided delivery to ablate peripheral pain fibers in swine. Under CT guidance, RTX was delivered unilaterally around the lumbar dorsal root ganglia (DRG), and vehicle only was administered to the contralateral side. During a 4-week observation period, animals demonstrated delayed or absent withdrawal responses to infrared laser heat stimuli delivered to sensory dermatomes corresponding to DRG receiving RTX treatment. Motor function was unimpaired as assessed by disability scoring and gait analysis. In treated DRG, TRPV1 mRNA expression was reduced, as were nociceptive neuronal perikarya in ganglia and their nerve terminals in the ipsilateral dorsal horn. CT guidance to precisely deliver RTX to sites of peripheral pain transmission in swine may be an approach that could be tailored to block an array of clinical pain conditions in patients. PMID:26378245

  12. Accumulation of Misfolded SOD1 in Dorsal Root Ganglion Degenerating Proprioceptive Sensory Neurons of Transgenic Mice with Amyotrophic Lateral Sclerosis

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    Javier Sábado

    2014-01-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is an adult-onset progressive neurodegenerative disease affecting upper and lower motoneurons (MNs. Although the motor phenotype is a hallmark for ALS, there is increasing evidence that systems other than the efferent MN system can be involved. Mutations of superoxide dismutase 1 (SOD1 gene cause a proportion of familial forms of this disease. Misfolding and aggregation of mutant SOD1 exert neurotoxicity in a noncell autonomous manner, as evidenced in studies using transgenic mouse models. Here, we used the SOD1G93A mouse model for ALS to detect, by means of conformational-specific anti-SOD1 antibodies, whether misfolded SOD1-mediated neurotoxicity extended to neuronal types other than MNs. We report that large dorsal root ganglion (DRG proprioceptive neurons accumulate misfolded SOD1 and suffer a degenerative process involving the inflammatory recruitment of macrophagic cells. Degenerating sensory axons were also detected in association with activated microglial cells in the spinal cord dorsal horn of diseased animals. As large proprioceptive DRG neurons project monosynaptically to ventral horn MNs, we hypothesise that a prion-like mechanism may be responsible for the transsynaptic propagation of SOD1 misfolding from ventral horn MNs to DRG sensory neurons.

  13. Human dorsal striatal activity during choice discriminates reinforcement learning behavior from the gambler's fallacy.

    Science.gov (United States)

    Jessup, Ryan K; O'Doherty, John P

    2011-04-27

    Reinforcement learning theory has generated substantial interest in neurobiology, particularly because of the resemblance between phasic dopamine and reward prediction errors. Actor-critic theories have been adapted to account for the functions of the striatum, with parts of the dorsal striatum equated to the actor. Here, we specifically test whether the human dorsal striatum--as predicted by an actor-critic instantiation--is used on a trial-to-trial basis at the time of choice to choose in accordance with reinforcement learning theory, as opposed to a competing strategy: the gambler's fallacy. Using a partial-brain functional magnetic resonance imaging scanning protocol focused on the striatum and other ventral brain areas, we found that the dorsal striatum is more active when choosing consistent with reinforcement learning compared with the competing strategy. Moreover, an overlapping area of dorsal striatum along with the ventral striatum was found to be correlated with reward prediction errors at the time of outcome, as predicted by the actor-critic framework. These findings suggest that the same region of dorsal striatum involved in learning stimulus-response associations may contribute to the control of behavior during choice, thereby using those learned associations. Intriguingly, neither reinforcement learning nor the gambler's fallacy conformed to the optimal choice strategy on the specific decision-making task we used. Thus, the dorsal striatum may contribute to the control of behavior according to reinforcement learning even when the prescriptions of such an algorithm are suboptimal in terms of maximizing future rewards.

  14. Growth of rat dorsal root ganglion neurons on a novel self-assembling scaffold containing IKVAV sequence

    Energy Technology Data Exchange (ETDEWEB)

    Zou Zhenwei; Zheng Qixin [Department of Orthopaedics, Union Hospital, Tongji Medical college of Huazhong University of science and technology, Wuhan, 430022 (China); Wu Yongchao, E-mail: wuyongchao@hotmail.com [Department of Orthopaedics, Union Hospital, Tongji Medical college of Huazhong University of science and technology, Wuhan, 430022 (China); Song Yulin; Wu Bin [Department of Orthopaedics, Union Hospital, Tongji Medical college of Huazhong University of science and technology, Wuhan, 430022 (China)

    2009-08-31

    The potential benefits of self-assembly in synthesizing materials for the treatment of both peripheral and central nervous system disorders are tremendous. In this study, we synthesized peptide-amphiphile (PA) molecules containing IKVAV sequence and induced self-assembly of the PA solutions in vitro to form nanofiber gels. Then, we tested the characterization of gels by transmission electron microscopy and demonstrated the biocompatibility of this gel towards rat dorsal root ganglion neurons. The nanofiber gel was formed by self-assembly of IKVAV PA molecules, which was triggered by metal ions. The fibers were 7-8 nm in diameter and with lengths of hundreds of nanometers. Gels were shown to be non-toxic to neurons and able to promote neurons adhesion and neurite sprouting. The results indicated that the self-assembling scaffold containing IKVAV sequence had excellent biocompatibility with adult sensory neurons and could be useful in nerve tissue engineering.

  15. Selective Small Molecule Activators of TREK-2 Channels Stimulate Dorsal Root Ganglion c-Fiber Nociceptor Two-Pore-Domain Potassium Channel Currents and Limit Calcium Influx.

    Science.gov (United States)

    Dadi, Prasanna K; Vierra, Nicholas C; Days, Emily; Dickerson, Matthew T; Vinson, Paige N; Weaver, C David; Jacobson, David A

    2017-03-15

    The two-pore-domain potassium (K2P) channel TREK-2 serves to modulate plasma membrane potential in dorsal root ganglia c-fiber nociceptors, which tunes electrical excitability and nociception. Thus, TREK-2 channels are considered a potential therapeutic target for treating pain; however, there are currently no selective pharmacological tools for TREK-2 channels. Here we report the identification of the first TREK-2 selective activators using a high-throughput fluorescence-based thallium (Tl+) flux screen (HTS). An initial pilot screen with a bioactive lipid library identified 11-deoxy prostaglandin F2α as a potent activator of TREK-2 channels (EC50 ≈ 0.294 μM), which was utilized to optimize the TREK-2 Tl+ flux assay (Z' = 0.752). A HTS was then performed with 76 575 structurally diverse small molecules. Many small molecules that selectively activate TREK-2 were discovered. As these molecules were able to activate single TREK-2 channels in excised membrane patches, they are likely direct TREK-2 activators. Furthermore, TREK-2 activators reduced primary dorsal root ganglion (DRG) c-fiber Ca2+ influx. Interestingly, some of the selective TREK-2 activators such as 11-deoxy prostaglandin F2α were found to inhibit the K2P channel TREK-1. Utilizing chimeric channels containing portions of TREK-1 and TREK-2, the region of the TREK channels that allows for either small molecule activation or inhibition was identified. This region lies within the second pore domain containing extracellular loop and is predicted to play an important role in modulating TREK channel activity. Moreover, the selective TREK-2 activators identified in this HTS provide important tools for assessing human TREK-2 channel function and investigating their therapeutic potential for treating chronic pain.

  16. Dorsal Root Ganglion Stimulation as a Salvage Treatment for Complex Regional Pain Syndrome Refractory to Dorsal Column Spinal Cord Stimulation: A Case Series.

    Science.gov (United States)

    Yang, Ajax; Hunter, Corey W

    2017-10-01

    The efficacy of traditional spinal cord stimulation (t-SCS) tends to decay over time in patients with complex regional pain syndrome (CRPS). While it has been shown that dorsal root ganglion (DRG) stimulation is extremely effective in t-SCS-naïve patients with CRPS, its efficacy in patients who had previously failed t-SCS is unknown. Given that DRG-SCS and t-SCS target different spinal pathways, a failure with t-SCS should not automatically preclude a patient from attempting DRG-SCS. Two patients with lower extremity CRPS, previously implanted with t-SCS systems, experienced relapses in the pain despite exhaustive reprogramming. Both patients were offered DRG stimulation as a means to salvage treatment. Patient 1 reported 90% pain reduction with significant gait improvement during the DRG stimulation trial. The patient subsequently proceeded to implant and have the t-SCS implantable pulse generator explanted. Patient 2 was unable to undergo a trial with DRG-SCS because of health insurance constraints, so she elected to undergo a surgical revision of her existing system whereby a DRG-SCS system was added to the existing t-SCS to create a hybrid system with two implantable pulse generators. The patient reported an immediate improvement in pain because of the introduction of the DRG-SCS. Additionally, she was instructed to document her pain scores with each system on individually, as well as with both on-her pain scores were at the lowest with the DRG-SCS on by itself. At eight-month follow-up, both patients reported sustained pain improvement and retained their functional gains. Our case series demonstrates that a failure of t-SCS is not necessarily a failure of neurostimulation as a whole. The efficacy of DRG-SCS is independent of prior t-SCS therapy outcomes in these two patients and a history of t-SCS failure serves no predictive value in these two patients for future DRG stimulation success. Therefore, DRG-SCS can be considered as a reasonable next-step to

  17. Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons

    Directory of Open Access Journals (Sweden)

    Chiaki Murayama

    2015-08-01

    Full Text Available Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH, a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF in cultured rat dorsal root ganglion (DRG neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control, a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in “itch-scratch” animal models is under investigation.

  18. Uncovering a context-specific connectional fingerprint of human dorsal premotor cortex

    DEFF Research Database (Denmark)

    Moisa, Marius; Siebner, Hartwig R; Pohmann, Rolf

    2012-01-01

    Primate electrophysiological and lesion studies indicate a prominent role of the left dorsal premotor cortex (PMd) in action selection based on learned sensorimotor associations. Here we applied transcranial magnetic stimulation (TMS) to human left PMd at low or high intensity while right-handed ...

  19. Human Dorsal Striatum Encodes Prediction Errors during Observational Learning of Instrumental Actions

    Science.gov (United States)

    Cooper, Jeffrey C.; Dunne, Simon; Furey, Teresa; O'Doherty, John P.

    2012-01-01

    The dorsal striatum plays a key role in the learning and expression of instrumental reward associations that are acquired through direct experience. However, not all learning about instrumental actions require direct experience. Instead, humans and other animals are also capable of acquiring instrumental actions by observing the experiences of…

  20. The effects of ropivacaine hydrochloride on the expression of CaMK II mRNA in the dorsal root ganglion neurons.

    Science.gov (United States)

    Wen, Xianjie; Lai, Xiaohong; Li, Xiaohong; Zhang, Tao; Liang, Hua

    2016-12-01

    In this study, we identified the subtype of Calcium/calmodulin-dependent protein kinase II (CaMK II) mRNA in dorsal root ganglion neurons and observed the effects of ropivacaine hydrochloride in different concentration and different exposure time on the mRNA expression. Dorsal root ganglion neurons were isolated from the SD rats and cultured in vitro. The mRNA of the CaMK II subtype in dorsal root ganglion neurons were detected by real-time PCR. As well as, the dorsal root ganglion neurons were treated with ropivacaine hydrochloride in different concentration (1mM,2mM, 3mM and 4mM) for the same exposure time of 4h, or different exposure time (0h,2h,3h,4h and 6h) at the same concentration(3mM). The changes of the mRNA expression of the CaMK II subtype were observed with real-time PCR. All subtype mRNA of the CaMK II, CaMK IIα, CaMK IIβ, CaMK II δ, CaMK IIγ, can be detected in dorsal root ganglion neurons. With the increased of the concentration and exposure time of the ropivacaine hydrochloride, all the subtype mRNA expression increased. Ropivacaine hydrochloride up-regulate the CaMK IIβ, CaMK IIδ, CaMK IIg mRNA expression with the concentration and exposure time increasing. The nerve blocking or the neurotoxicity of the ropivacaine hydrochloride maybe involved with CaMK II. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. Malformations of the tooth root in humans

    Directory of Open Access Journals (Sweden)

    Hans Ulrich eLuder

    2015-10-01

    Full Text Available The most common root malformations in humans arise from either developmental disorders of the root alone or disorders of radicular development as part of a general tooth dysplasia. The aim of this review is to relate the characteristics of these root malformations to potentially disrupted processes involved in radicular morphogenesis. Radicular morphogenesis proceeds under the control of Hertwig's epithelial root sheath (HERS which determines the number, length, and shape of the root, induces the formation of radicular dentin, and participates in the development of root cementum. Formation of HERS at the transition from crown to root development appears to be very insensitive to adverse effects, with the result that rootless teeth are extremely rare. In contrast, shortened roots as a consequence of impaired or prematurely halted apical growth of HERS constitute the most prevalent radicular dysplasia which occurs due to trauma and unknown reasons as well as in association with dentin disorders. While odontoblast differentiation inevitably stops when growth of HERS is arrested, it seems to be unaffected even in cases of severe dentin dysplasias such as regional odontodysplasia and dentin dysplasia type I. As a result radicular dentin formation is at least initiated and progresses for a limited time. The only condition affecting cementogenesis is hypophosphatasia which disrupts the formation of acellular cementum through an inhibition of mineralization. A process particularly susceptible to adverse effects appears to be the formation of the furcation in multirooted teeth. Impairment or disruption of this process entails taurodontism, single-rooted posterior teeth, and misshapen furcations. Thus even though many characteristics of human root malformations can be related to disorders of specific processes involved in radicular morphogenesis, precise inferences as to the pathogenesis of these dysplasias are hampered by the still limited knowledge on

  2. Malformations of the tooth root in humans.

    Science.gov (United States)

    Luder, Hans U

    2015-01-01

    The most common root malformations in humans arise from either developmental disorders of the root alone or disorders of radicular development as part of a general tooth dysplasia. The aim of this review is to relate the characteristics of these root malformations to potentially disrupted processes involved in radicular morphogenesis. Radicular morphogenesis proceeds under the control of Hertwig's epithelial root sheath (HERS) which determines the number, length, and shape of the root, induces the formation of radicular dentin, and participates in the development of root cementum. Formation of HERS at the transition from crown to root development appears to be very insensitive to adverse effects, with the result that rootless teeth are extremely rare. In contrast, shortened roots as a consequence of impaired or prematurely halted apical growth of HERS constitute the most prevalent radicular dysplasia which occurs due to trauma and unknown reasons as well as in association with dentin disorders. While odontoblast differentiation inevitably stops when growth of HERS is arrested, it seems to be unaffected even in cases of severe dentin dysplasias such as regional odontodysplasia and dentin dysplasia type I. As a result radicular dentin formation is at least initiated and progresses for a limited time. The only condition affecting cementogenesis is hypophosphatasia which disrupts the formation of acellular cementum through an inhibition of mineralization. A process particularly susceptible to adverse effects appears to be the formation of the furcation in multirooted teeth. Impairment or disruption of this process entails taurodontism, single-rooted posterior teeth, and misshapen furcations. Thus, even though many characteristics of human root malformations can be related to disorders of specific processes involved in radicular morphogenesis, precise inferences as to the pathogenesis of these dysplasias are hampered by the still limited knowledge on root formation.

  3. Malformations of the tooth root in humans

    Science.gov (United States)

    Luder, Hans U.

    2015-01-01

    The most common root malformations in humans arise from either developmental disorders of the root alone or disorders of radicular development as part of a general tooth dysplasia. The aim of this review is to relate the characteristics of these root malformations to potentially disrupted processes involved in radicular morphogenesis. Radicular morphogenesis proceeds under the control of Hertwig's epithelial root sheath (HERS) which determines the number, length, and shape of the root, induces the formation of radicular dentin, and participates in the development of root cementum. Formation of HERS at the transition from crown to root development appears to be very insensitive to adverse effects, with the result that rootless teeth are extremely rare. In contrast, shortened roots as a consequence of impaired or prematurely halted apical growth of HERS constitute the most prevalent radicular dysplasia which occurs due to trauma and unknown reasons as well as in association with dentin disorders. While odontoblast differentiation inevitably stops when growth of HERS is arrested, it seems to be unaffected even in cases of severe dentin dysplasias such as regional odontodysplasia and dentin dysplasia type I. As a result radicular dentin formation is at least initiated and progresses for a limited time. The only condition affecting cementogenesis is hypophosphatasia which disrupts the formation of acellular cementum through an inhibition of mineralization. A process particularly susceptible to adverse effects appears to be the formation of the furcation in multirooted teeth. Impairment or disruption of this process entails taurodontism, single-rooted posterior teeth, and misshapen furcations. Thus, even though many characteristics of human root malformations can be related to disorders of specific processes involved in radicular morphogenesis, precise inferences as to the pathogenesis of these dysplasias are hampered by the still limited knowledge on root formation

  4. eIF4E Phosphorylation Influences Bdnf mRNA Translation in Mouse Dorsal Root Ganglion Neurons

    Directory of Open Access Journals (Sweden)

    Jamie K. Moy

    2018-02-01

    Full Text Available Plasticity in dorsal root ganglion (DRG neurons that promotes pain requires activity-dependent mRNA translation. Protein synthesis inhibitors block the ability of many pain-promoting molecules to enhance excitability in DRG neurons and attenuate behavioral signs of pain plasticity. In line with this, we have recently shown that phosphorylation of the 5′ cap-binding protein, eIF4E, plays a pivotal role in plasticity of DRG nociceptors in models of hyperalgesic priming. However, mRNA targets of eIF4E phosphorylation have not been elucidated in the DRG. Brain-derived neurotrophic factor (BDNF signaling from nociceptors in the DRG to spinal dorsal horn neurons is an important mediator of hyperalgesic priming. Regulatory mechanisms that promote pain plasticity via controlling BDNF expression that is involved in promoting pain plasticity have not been identified. We show that phosphorylation of eIF4E is paramount for Bdnf mRNA translation in the DRG. Bdnf mRNA translation is reduced in mice lacking eIF4E phosphorylation (eIF4ES209A and pro-nociceptive factors fail to increase BDNF protein levels in the DRGs of these mice despite robust upregulation of Bdnf-201 mRNA levels. Importantly, bypassing the DRG by giving intrathecal injection of BDNF in eIF4ES209A mice creates a strong hyperalgesic priming response that is normally absent or reduced in these mice. We conclude that eIF4E phosphorylation-mediated translational control of BDNF expression is a key mechanism for nociceptor plasticity leading to hyperalgesic priming.

  5. Perception and Action Selection Dissociate Human Ventral and Dorsal Cortex

    Science.gov (United States)

    Ikkai, Akiko; Jerde, Trenton A.; Curtis, Clayton E.

    2011-01-01

    We test theories about the functional organization of the human cortex by correlating brain activity with demands on perception versus action selection. Subjects covertly searched for a target among an array of 4, 8, or 12 items (perceptual manipulation) and then, depending on the color of the array, made a saccade toward, away from, or at a right…

  6. A SCN9A gene-encoded dorsal root ganglia sodium channel polymorphism associated with severe fibromyalgia

    Directory of Open Access Journals (Sweden)

    Vargas-Alarcon Gilberto

    2012-02-01

    Full Text Available Abstract Background A consistent line of investigation suggests that autonomic nervous system dysfunction may explain the multi-system features of fibromyalgia (FM; and that FM is a sympathetically maintained neuropathic pain syndrome. Dorsal root ganglia (DRG are key sympathetic-nociceptive short-circuit sites. Sodium channels located in DRG (particularly Nav1.7 act as molecular gatekeepers for pain detection. Nav1.7 is encoded in gene SCN9A of chromosome 2q24.3 and is predominantly expressed in the DRG pain-sensing neurons and sympathetic ganglia neurons. Several SCN9A sodium channelopathies have been recognized as the cause of rare painful dysautonomic syndromes such as paroxysmal extreme pain disorder and primary erythromelalgia. The aim of this study was to search for an association between fibromyalgia and several SCN9A sodium channels gene polymorphisms. Methods We studied 73 Mexican women suffering from FM and 48 age-matched women who considered themselves healthy. All participants filled out the Fibromyalgia Impact Questionnaire (FIQ. Genomic DNA from whole blood containing EDTA was extracted by standard techniques. The following SCN9A single-nucleotide polymorphisms (SNP were determined by 5' exonuclease TaqMan assays: rs4371369; rs4387806; rs4453709; rs4597545; rs6746030; rs6754031; rs7607967; rs12620053; rs12994338; and rs13017637. Results The frequency of the rs6754031 polymorphism was significantly different in both groups (P = 0.036 mostly due to an absence of the GG genotype in controls. Interestingly; patients with this rs6754031 GG genotype had higher FIQ scores (median = 80; percentile 25/75 = 69/88 than patients with the GT genotype (median = 63; percentile 25/75 = 58/73; P = 0.002 and the TT genotype (median = 71; percentile 25/75 = 64/77; P = 0.001. Conclusion In this ethnic group; a disabling form of FM is associated to a particular SCN9A sodium channel gene variant. These preliminary results raise the possibility that

  7. Superficial dorsal horn of the adult human spinal cord.

    Science.gov (United States)

    Bowsher, D; Abdel-Maguid, T E

    1984-12-01

    Golgi studies in the adult human spinal cord reveal 10 cell types in the first three laminae. Five are Golgi Type II or ipsilateral proprioneurons of short or long range--the latter including Waldeyer cells. Several of the cells in this group have dendrites that help to form interlaminar boundaries on the gray-white boundary. Two of the four cell types in Lamina II have dendritic fields that correspond exactly to the primary afferent terminal axonal fields described in the cat by Rethelyi (1977). Three cell types, one in each lamina, can be tentatively homologized with monkey spinothalamic cells described by other authors. Our previously described classification method based on dendritic patterns suggests that the Golgi Type II interneurons and ipsilateral proprioneurons belong to two different cell families (and Waldeyer cells to a third), whereas the putative spinothalamic neurons are all different cell types.

  8. Large dense-core vesicle exocytosis from mouse dorsal root ganglion neurons is regulated by neuropeptide Y.

    Science.gov (United States)

    Bost, Anneka; Shaib, Ali H; Schwarz, Yvonne; Niemeyer, Barbara A; Becherer, Ute

    2017-03-27

    Peptidergic dorsal root ganglion (DRG) neurons transmit sensory and nociceptive information from the periphery to the central nervous system. Their synaptic activity is profoundly affected by neuromodulatory peptides stored and released from large dense-core vesicles (LDCVs). However, the mechanism of peptide secretion from DRG neurons is poorly understood. Using total internal reflection fluorescence microscopy (TIRFM), we visualized individual LDCVs loaded with fluorescent neuropeptide Y (NPY) and analyzed their stimulation-dependent release. We tested several protocols and found an overall low stimulation-secretion coupling that increased after raising intracellular Ca 2+ concentration by applying a weak pre-stimulus. Interestingly, the stimulation protocol also influenced the mechanism of LDCV fusion. Depolarization of DRG neurons with a solution containing 60mM KCl triggered full fusion, kiss-and-run, and kiss-and-stay exocytosis with equal frequency. In contrast, field electrode stimulation primarily induced full fusion exocytosis. Finally, our results indicate that NPY can promote LDCV secretion. These results shed new light on the mechanism of NPY action during modulation of DRG neuron activity, an important pathway in the treatment of chronic pain. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Functional properties and toxin pharmacology of a dorsal root ganglion sodium channel viewed through its voltage sensors

    Science.gov (United States)

    Puopolo, Michelino; Martin-Eauclaire, Marie-France; Bean, Bruce P.

    2011-01-01

    The voltage-activated sodium (Nav) channel Nav1.9 is expressed in dorsal root ganglion (DRG) neurons where it is believed to play an important role in nociception. Progress in revealing the functional properties and pharmacological sensitivities of this non-canonical Nav channel has been slow because attempts to express this channel in a heterologous expression system have been unsuccessful. Here, we use a protein engineering approach to dissect the contributions of the four Nav1.9 voltage sensors to channel function and pharmacology. We define individual S3b–S4 paddle motifs within each voltage sensor, and show that they can sense changes in membrane voltage and drive voltage sensor activation when transplanted into voltage-activated potassium channels. We also find that the paddle motifs in Nav1.9 are targeted by animal toxins, and that these toxins alter Nav1.9-mediated currents in DRG neurons. Our results demonstrate that slowly activating and inactivating Nav1.9 channels have functional and pharmacological properties in common with canonical Nav channels, but also show distinctive pharmacological sensitivities that can potentially be exploited for developing novel treatments for pain. PMID:21670206

  10. Phantom Remodeling Effect of Dorsal Root Entry Zone Lesioning in Phantom Limb Pain Caused by Brachial Plexus Avulsion.

    Science.gov (United States)

    Son, Byung-Chul; Ha, Sang-Woo

    2015-01-01

    Dorsal root entry zone (DREZ) lesioning has been reported to be effective for phantom limb pain caused by brachial plexus avulsion pain. Most reports on DREZ lesioning for brachial plexus avulsion pain have focused on the results of pain relief without a detailed description of phantom sensations following DREZ lesioning. Two patients (1 with amputation and the other nonamputated) with chronic intractable phantom limb pain caused by brachial plexus avulsion underwent DREZ lesioning on the avulsed segments of the cervical spinal cords. Changes of the phantom limb were observed. Immediately following DREZ lesioning, the phantom limb pain disappeared in the amputee, the phantom arm was shortened and the phantom hand disappeared. The other patient with the nonamputated arm reported an immediate 50% reduction in the size of the phantom hand, and pain relief was up to 70% of the preoperative phantom limb pain. There was no further change in the phantom arm and hand during the follow-up of 1.5-2 years. The phantom arms and hands showed a prompt shortening and reduction in size, rather than a disappearance, following successful DREZ lesioning in patients with chronic phantom limb pain caused by brachial plexus avulsion. © 2015 S. Karger AG, Basel.

  11. Channelrhodopsin-2-expressed dorsal root ganglion neurons activates calcium channel currents and increases action potential in spinal cord.

    Science.gov (United States)

    Zhang, Yi; Yue, Jing; Ai, Midan; Ji, Zhigang; Liu, Zhiguo; Cao, Xuehong; Li, Li

    2014-07-01

    We used optogenetic techniques in spinal cord and dorsal root ganglion (DRG) neuron studies. This study investigated changes in channelrhodopsin-2 (ChR2) expression in the spinal cord and DRG neurons using optogenetic techniques. The results show the possibility of using optogenetics to treat neuropathic pain. Previous studies have shown that activated ChR2 induces an increase in DRG neuron action potential. Western blot analysis was used to measure ChR2 protein levels in the spinal cord and DRG neurons or rats intrathecally injected with ChR2 lentivirus. Electrophysiology recording was used to detect differences in action potential levels in the spinal cord and calcium channel currents in the DRG neurons. Our studies showed that ChR2 expression increased the action potential in the spinal cord and increased calcium channel currents in DRG neurons. We successfully expressed the ChR2 protein in the spinal cord and DRG neurons. We also found that ChR2 increased the action potential in the spinal cord and activated the calcium channel in DRG neurons. These findings support the research possibilities of using optogenetic studies to improve treatment for neuropathic pain. N/A.

  12. Controlled release of 6-aminonicotinamide from aligned, electrospun fibers alters astrocyte metabolism and dorsal root ganglia neurite outgrowth

    Science.gov (United States)

    Schaub, Nicholas J.; Gilbert, Ryan J.

    2011-08-01

    Following central nervous system (CNS) injury, activated astrocytes form a glial scar that inhibits the migration of axons ultimately leading to regeneration failure. Biomaterials developed for CNS repair can provide local delivery of therapeutics and/or guidance mechanisms to encourage cell migration into damaged regions of the brain or spinal cord. Electrospun fibers are a promising type of biomaterial for CNS injury since these fibers can direct cellular and axonal migration while slowly delivering therapy to the injury site. In this study, it was hypothesized that inclusion of an anti-metabolite, 6-aminonicotinamide (6AN), within poly-l-lactic acid electrospun fibers could attenuate astrocyte metabolic activity while still directing axonal outgrowth. Electrospinning parameters were varied to produce highly aligned electrospun fibers that contained 10% or 20% (w/w) 6AN. 6AN release from the fiber substrates occurred continuously over 2 weeks. Astrocytes placed onto drug-releasing fibers were less active than those cultured on scaffolds without 6AN. Dorsal root ganglia placed onto control and drug-releasing scaffolds were able to direct neurites along the aligned fibers. However, neurite outgrowth was stunted by fibers that contained 20% 6AN. These results show that 6AN release from aligned, electrospun fibers can decrease astrocyte activity while still directing axonal outgrowth.

  13. Caspase-2 and microRNA34a/c regulate lidocaine-induced dorsal root ganglia apoptosis in vitro.

    Science.gov (United States)

    Li, Yandong; Jia, Zhi; Zhang, Laizhu; Wang, Jianguo; Yin, Guangming

    2015-11-15

    Epidural administration of lidocaine may cause neurotoxicity in spinal cord dorsal root ganglia neurons (DRGNs). In this study, we explored the underling mechanisms of apoptotic pathways of lidocaine-induced apoptosis in DRGNs. Neonatal rat DRGNs were treated with lidocaine to induced apoptosis in vitro. Western blot showed caspase- (casp-) 2/3/9 proteins were all upregulated by lidocaine in DRGNs. However, inhibition of casp-2 protected lidocaine-induced apoptosis in DRGNs, whereas Casp3/9 inhibition did not. The possible upstream epigenetic regulators of casp-2, microRNA-34 (miR-34) family, including miR-34a/b/c, were evaluated by dual-luciferase reporter assay and qRT-PCR. We found miR-34a/c, but not miR-34b, were down-regulated in lidocaine-induced DRGN apoptosis. Subsequent upregulation of miR-34 family showed miR-34a/c were able to inhibit casp-2 and protect lidocaine-induced apoptosis in DRGNs, whereas miR-34b did not. Thus, out study shows that casp-2, in association with miR-34a/c was actively involved in lidocaine-induced apoptosis in DRGNs. Inhibiting casp-2 or upregulating miR-34a/c may provide novel meanings to protect local anesthetic-induced neurotoxicity. Copyright © 2015. Published by Elsevier B.V.

  14. Vascularization of the dorsal root ganglia and peripheral nerve of the mouse: Implications for chemical-induced peripheral sensory neuropathies

    Directory of Open Access Journals (Sweden)

    Melemedjian Ohannes K

    2008-03-01

    Full Text Available Abstract Although a variety of industrial chemicals, as well as several chemotherapeutic agents used to treat cancer or HIV, preferentially induce a peripheral sensory neuropathy what remains unclear is why these agents induce a sensory vs. a motor or mixed neuropathy. Previous studies have shown that the endothelial cells that vascularize the dorsal root ganglion (DRG, which houses the primary afferent sensory neurons, are unique in that they have large fenestrations and are permeable to a variety of low and high molecular weight agents. In the present report we used whole-mount preparations, immunohistochemistry, and confocal laser scanning microscopy to show that the cell body-rich area of the L4 mouse DRG has a 7 fold higher density of CD31+ capillaries than cell fiber rich area of the DRG or the distal or proximal aspect of the sciatic nerve. This dense vascularization, coupled with the high permeability of these capillaries, may synergistically contribute, and in part explain, why many potentially neurotoxic agents preferentially accumulate and injure cells within the DRG. Currently, cancer survivors and HIV patients constitute the largest and most rapidly expanding groups that have chemically induced peripheral sensory neuropathy. Understanding the unique aspects of the vascularization of the DRG and closing the endothelial fenestrations of the rich vascular bed of capillaries that vascularize the DRG before intravenous administration of anti-neoplastic or anti-HIV therapies, may offer a mechanism based approach to attenuate these chemically induced peripheral neuropathies in these patients.

  15. Abnormalities in spinal neurons and dorsal root ganglion cells in Tangier disease presenting with a syringomyelia-like syndrome.

    Science.gov (United States)

    Schmalbruch, H; Stender, S; Boysen, G

    1987-09-01

    A woman with homozygous Tangier disease had progressive syringomyelia-like neuropathy. She died with cardiac failure at age 61. A sural nerve biopsy taken at age 60 had shown lipid storage in Schwann and interstitial cells, and a pronounced loss of unmyelinated fibers. The neurons of the L5 spinal ganglion and, to a lesser extent, all neurons of the sacral spinal cord, contained large lipid inclusions which in electron micrographs differed from those in Schwann and satellite cells. There was no storage material in glial cells. The neuronal inclusions were membrane-bound and consisted of electron-dense and electron-lucent components. There was evidence of neuronal death in the spinal ganglion, and a diameter histogram showed that small cytons had preferentially been lost. The inclusions probably were secondary lysosomes or residual bodies, and resembled giant lipofuscin granules. Nevertheless, they were uncolored and displayed weak autofluorescence as compared to the aging pigment in control ganglia. It is tentatively suggested that the syringomyelia-like neuropathy in Tangier disease represents a lysosomal storage disorder preferentially affecting small dorsal root ganglion cells.

  16. Functional properties and toxin pharmacology of a dorsal root ganglion sodium channel viewed through its voltage sensors.

    Science.gov (United States)

    Bosmans, Frank; Puopolo, Michelino; Martin-Eauclaire, Marie-France; Bean, Bruce P; Swartz, Kenton J

    2011-07-01

    The voltage-activated sodium (Nav) channel Nav1.9 is expressed in dorsal root ganglion (DRG) neurons where it is believed to play an important role in nociception. Progress in revealing the functional properties and pharmacological sensitivities of this non-canonical Nav channel has been slow because attempts to express this channel in a heterologous expression system have been unsuccessful. Here, we use a protein engineering approach to dissect the contributions of the four Nav1.9 voltage sensors to channel function and pharmacology. We define individual S3b-S4 paddle motifs within each voltage sensor, and show that they can sense changes in membrane voltage and drive voltage sensor activation when transplanted into voltage-activated potassium channels. We also find that the paddle motifs in Nav1.9 are targeted by animal toxins, and that these toxins alter Nav1.9-mediated currents in DRG neurons. Our results demonstrate that slowly activating and inactivating Nav1.9 channels have functional and pharmacological properties in common with canonical Nav channels, but also show distinctive pharmacological sensitivities that can potentially be exploited for developing novel treatments for pain.

  17. Real-time control of hind limb functional electrical stimulation using feedback from dorsal root ganglia recordings

    Science.gov (United States)

    Bruns, Tim M.; Wagenaar, Joost B.; Bauman, Matthew J.; Gaunt, Robert A.; Weber, Douglas J.

    2013-04-01

    Objective. Functional electrical stimulation (FES) approaches often utilize an open-loop controller to drive state transitions. The addition of sensory feedback may allow for closed-loop control that can respond effectively to perturbations and muscle fatigue. Approach. We evaluated the use of natural sensory nerve signals obtained with penetrating microelectrode arrays in lumbar dorsal root ganglia (DRG) as real-time feedback for closed-loop control of FES-generated hind limb stepping in anesthetized cats. Main results. Leg position feedback was obtained in near real-time at 50 ms intervals by decoding the firing rates of more than 120 DRG neurons recorded simultaneously. Over 5 m of effective linear distance was traversed during closed-loop stepping trials in each of two cats. The controller compensated effectively for perturbations in the stepping path when DRG sensory feedback was provided. The presence of stimulation artifacts and the quality of DRG unit sorting did not significantly affect the accuracy of leg position feedback obtained from the linear decoding model as long as at least 20 DRG units were included in the model. Significance. This work demonstrates the feasibility and utility of closed-loop FES control based on natural neural sensors. Further work is needed to improve the controller and electrode technologies and to evaluate long-term viability.

  18. One cell model establishment to inhibit CaMKIIγ mRNA expression in the dorsal root ganglion neuron by RNA interfere.

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    Wen, Xianjie; Li, Xiaohong; Liang, Hua; Yang, Chenxiang; Zhong, Jiying; Wang, Hanbing; Liu, Hongzhen

    2017-09-01

    CaMKIIγ in dorsal root ganglion neurons is closely related to the neuropathic pain, neuron injury induced by local anesthetics. To get great insight into the function of CaMKIIγ in dorsal root ganglion neurons, we need one cell model to specially inhibit the CaMKIIγ mRNA expression. The present study was aimed to establish one cell model to specially inhibit the CaMKIIγ mRNA expression. We designed the CaMKIIγ shRNA sequence and connected with pYr-1.1 plasmid. The ligation product of the CaMKIIγshRNA and pYr-1.1 plasmid was recombined with pAd/PL-DEST vector into pAD-CaMKIIγ-shRNA. adenovirus vector. pAD-CaMKIIγ-shRNA. adenovirus vector infected the dorsal root ganglion neuron to inhibit the CaMKIIγ mRNA expression in vitro. The pAD-CaMKIIγ-shRNA adenovirus vector was verified to be correct by the digestion, sequence. And pAD-CaMKIIγ-shRNA. adenovirus vector can infect the DRG cells to inhibit the CaMKIIγ mRNA or protein expression by the real-time polymerase chain reaction (PCR) or western blotting. Those results showed that we successfully constructed one adenovirus vector that can infect the dorsal root ganglion neuron to inhibit the CaMKIIγ mRNA and protein expression. That will supply with one cell model for the CaMKIIγ function study.

  19. Efficient Gene Suppression in Dorsal Root Ganglia and Spinal Cord Using Adeno-Associated Virus Vectors Encoding Short-Hairpin RNA.

    Science.gov (United States)

    Enomoto, Mitsuhiro; Hirai, Takashi; Kaburagi, Hidetoshi; Yokota, Takanori

    2016-01-01

    RNA interference is a powerful tool used to induce loss-of-function phenotypes through post-transcriptional gene silencing. Small interfering RNA (siRNA) molecules have been used to target the central nervous system (CNS) and are expected to have clinical utility against refractory neurodegenerative diseases. However, siRNA is characterized by low transduction efficiency, insufficient inhibition of gene expression, and short duration of therapeutic effects, and is thus not ideal for treatment of neural tissues and diseases. To address these problems, viral delivery of short-hairpin RNA (shRNA) expression cassettes that support more efficient and long-lasting transduction into target tissues is expected to be a promising delivery tool. Various types of gene therapy vectors have been developed, such as adenovirus, adeno-associated virus (AAV), herpes simplex virus and lentivirus; however, AAV is particularly advantageous because of its relative lack of immunogenicity and lack of chromosomal integration. In human clinical trials, recombinant AAV vectors are relatively safe and well-tolerated. In particular, serotype 9 of AAV (AAV9) vectors show the highest tropism for neural tissue and can cross the blood-brain barrier, and we have shown that intrathecal delivery of AAV9 yields relatively high gene transduction into dorsal root ganglia or spinal cord. This chapter describes how to successfully use AAV vectors encoding shRNA in vivo, particularly for RNA interference in the central and peripheral nervous system.

  20. [Effect of Triptolide on expression of NMDAR1 and BSI-B4 binding sites in spinal dorsal horn and dorsal root ganglion in rats with adjuvant arthritis].

    Science.gov (United States)

    Wei, Yun-bo; Lin, Rong; Chen, Wei; Zhang, Xu-dong; Lu, Zhuo-hui; Jiang, Wen-wen; Wei, Deng-ming

    2014-11-01

    To study the analgesic effect of Triptolide(TP) in rats with adjuvant and the possible mechanism. Fifty healthy SD rats were randomly divided into normal control group (group A), model group (group B), and low(group C), middle (group D) and high(group E) dose TP treatment groups. Except the group A, each group of rats were reared by toe intradermal injection of 0. 1 mL Freund's complete adjuvant. After 14 days,rats in the C, D and E groups were taken different doses (0. 1 mg/kg group C, 0. 2mg/kg group D, and 0. 4 mg/kg group E) by intraperitoneal injection of TP for 9 days, and then thermal withdrawal latency and the expression of NMDAR1 and BSI-B4 binding sites in lumbar5 (L5) spinal dorsal horn and DRG were detected. Thermal withdrawal latency of rats in group B was significantly lower than that of group A (P effect relationship; NMDAR-1 and BSI-B4 binding sites expression levels were significantly increased in group B than those in group A (P effect of TP is related to reducing levels of expression of NMDAR1 and BSI-B4 binding sites in spinal dorsal horn and DRG in rats with adjuvant arthritis.

  1. Clinical significance of the position of dorsal root ganglia in degenerative lumbar diseases. Correlation between anatomic study and imaging study with MRI

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Masahiro; Kikuchi, Tomiichi [Fukushima Medical Coll., Matsuoka (Japan)

    1995-06-01

    In order to estimate the ralationship between the position of dorsal root ganglia (DRG) and radicular symptoms, anatomical study was done on 81 cadavers, and a clinical study with MRI was done on 20 cases of lumbar disc herniation and 20 of lumbar spondylosis with L{sub 5} radiculopathy. The position of DRG is not related to the occurrence of radicular symptoms in disc herniation, while in lumbar spondylosis proximally placed DRG are related to both of unilateral and bilateral occurrence of redicular symptoms. Unilateral occurrence of radicular symptoms is influenced by surrounding tissues of the nerve root, rather than the position of DRG. (author).

  2. Dopamine modulation of transient receptor potential vanilloid type 1 (TRPV1) receptor in dorsal root ganglia neurons.

    Science.gov (United States)

    Chakraborty, Saikat; Rebecchi, Mario; Kaczocha, Martin; Puopolo, Michelino

    2016-03-15

    The transient receptor potential vanilloid type 1 (TRPV1) receptor plays a key role in the modulation of nociceptor excitability. To address whether dopamine can modulate the activity of TRPV1 channels in nociceptive neurons, the effects of dopamine and dopamine receptor agonists were tested on the capsaicin-activated current recorded from acutely dissociated small diameter (<27 μm) dorsal root ganglia (DRG) neurons. Dopamine or SKF 81297 (an agonist at D1/D5 receptors), caused inhibition of both inward and outward currents by ∼60% and ∼48%, respectively. The effect of SKF 81297 was reversed by SCH 23390 (an antagonist at D1/D5 receptors), confirming that it was mediated by activation of D1/D5 dopamine receptors. In contrast, quinpirole (an agonist at D2 receptors) had no significant effect on the capsaicin-activated current. Inhibition of the capsaicin-activated current by SKF 81297 was mediated by G protein coupled receptors (GPCRs), and highly dependent on external calcium. The inhibitory effect of SKF 81297 on the capsaicin-activated current was not affected when the protein kinase A (PKA) activity was blocked with H89, or when the protein kinase C (PKC) activity was blocked with bisindolylmaleimide II (BIM). In contrast, when the calcium-calmodulin-dependent protein kinase II (CaMKII) was blocked with KN-93, the inhibitory effect of SKF 81297 on the capsaicin-activated current was greatly reduced, suggesting that activation of D1/D5 dopamine receptors may be preferentially linked to CaMKII activity. We suggest that modulation of TRPV1 channels by dopamine in nociceptive neurons may represent a way for dopamine to modulate incoming noxious stimuli. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  3. Neonatal maternal deprivation sensitizes voltage-gated sodium channel currents in colon-specific dorsal root ganglion neurons in rats.

    Science.gov (United States)

    Hu, Shufen; Xiao, Ying; Zhu, Liyan; Li, Lin; Hu, Chuang-Ying; Jiang, Xinghong; Xu, Guang-Yin

    2013-02-15

    Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by abdominal pain in association with altered bowel movements. The underlying mechanisms of visceral hypersensitivity remain elusive. This study was designed to examine the role for sodium channels in a rat model of chronic visceral hyperalgesia induced by neonatal maternal deprivation (NMD). Abdominal withdrawal reflex (AWR) scores were performed on adult male rats. Colon-specific dorsal root ganglion (DRG) neurons were labeled with DiI and acutely dissociated for measuring excitability and sodium channel current under whole-cell patch-clamp configurations. The expression of Na(V)1.8 was analyzed by Western blot and quantitative real-time PCR. NMD significantly increased AWR scores, which lasted for ~6 wk in an association with hyperexcitability of colon DRG neurons. TTX-resistant but not TTX-sensitive sodium current density was greatly enhanced in colon DRG neurons in NMD rats. Compared with controls, activation curves showed a leftward shift in NMD rats whereas inactivation curves did not differ significantly. NMD markedly accelerated the activation time of peak current amplitude without any changes in inactivation time. Furthermore, NMD remarkably enhanced expression of Na(V)1.8 at protein levels but not at mRNA levels in colon-related DRGs. The expression of Na(V)1.9 was not altered after NMD. These data suggest that NMD enhances TTX-resistant sodium activity of colon DRG neurons, which is most likely mediated by a leftward shift of activation curve and by enhanced expression of Na(V)1.8 at protein levels, thus identifying a specific molecular mechanism underlying chronic visceral pain and sensitization in patients with IBS.

  4. Despite differences in cytosolic calcium regulation, lidocaine toxicity is similar in adult and neonatal rat dorsal root ganglia in vitro.

    Science.gov (United States)

    Doan, Lisa V; Eydlin, Olga; Piskoun, Boris; Kline, Richard P; Recio-Pinto, Esperanza; Rosenberg, Andrew D; Blanck, Thomas J J; Xu, Fang

    2014-01-01

    Neuraxial local anesthetics may have neurological complications thought to be due to neurotoxicity. A primary site of action of local anesthetics is the dorsal root ganglia (DRG) neuron. Physiologic differences have been noted between young and adult DRG neurons; hence, the authors examined whether there were any differences in lidocaine-induced changes in calcium and lidocaine toxicity in neonatal and adult rat DRG neurons. DRG neurons were cultured from postnatal day 7 (P7) and adult rats. Lidocaine-induced changes in cytosolic calcium were examined with the calcium indicator Fluo-4. Cells were incubated with varying concentrations of lidocaine and examined for viability using calcein AM and ethidium homodimer-1 staining. Live imaging of caspase-3/7 activation was performed after incubation with lidocaine. The mean KCl-induced calcium transient was greater in P7 neurons (P lidocaine significantly inhibited KCl-induced calcium responses in both ages (P lidocaine, KCl-induced calcium transients in both ages became more homogeneous but remained different between the groups. Interestingly, cell viability was decreased by lidocaine in a dose-dependent manner similarly in both ages. Lidocaine treatment also activated caspase-3/7 in a dose- and time-dependent manner similarly in both ages. Despite physiological differences in P7 and adult DRG neurons, lidocaine cytotoxicity is similar in P7 and adult DRG neurons in vitro. Differences in lidocaine- and KCl-evoked calcium responses suggest the similarity in lidocaine cytotoxicity involves other actions in addition to lidocaine-evoked effects on cytosolic calcium responses.

  5. Enhanced Expression of TREK-1 Is Related with Chronic Constriction Injury of Neuropathic Pain Mouse Model in Dorsal Root Ganglion.

    Science.gov (United States)

    Han, Hyo Jo; Lee, Seung Wook; Kim, Gyu-Tae; Kim, Eun-Jin; Kwon, Byeonghun; Kang, Dawon; Kim, Hyun Jeong; Seo, Kwang-Suk

    2016-05-01

    Neuropathic pain is a complex state showing increased pain response with dysfunctional inhibitory neurotransmission. The TREK family, one of the two pore domain K⁺ (K2P) channel subgroups were focused among various mechanisms of neuropathic pain. These channels influence neuronal excitability and are thought to be related in mechano/thermosensation. However, only a little is known about the expression and role of TREK-1 and TREK-2, in neuropathic pain. It is performed to know whether TREK-1 and/ or 2 are positively related in dorsal root ganglion (DRG) of a mouse neuropathic pain model, the chronic constriction injury (CCI) model. Following this purpose, Reverse Transcription Polymerase Chain Reaction (RT-PCR) and western blot analyses were performed using mouse DRG of CCI model and compared to the sham surgery group. Immunofluorescence staining of isolectin- B4 (IB4) and TREK were performed. Electrophysiological recordings of single channel currents were analyzed to obtain the information about the channel. Interactions with known TREK activators were tested to confirm the expression. While both TREK-1 and TREK-2 mRNA were significantly overexpressed in DRG of CCI mice, only TREK-1 showed significant increase (~9 fold) in western blot analysis. The TREK-1-like channel recorded in DRG neurons of the CCI mouse showed similar current-voltage relationship and conductance to TREK-1. It was easily activated by low pH solution (pH 6.3), negative pressure, and riluzole. Immunofluorescence images showed the expression of TREK-1 was stronger compared to TREK-2 on IB4 positive neurons. These results suggest that modulation of the TREK-1 channel may have beneficial analgesic effects in neuropathic pain patients.

  6. Despite Differences in Cytosolic Calcium Regulation, Lidocaine Toxicity Is Similar in Adult and Neonatal Rat Dorsal Root Ganglia in Vitro

    Science.gov (United States)

    Doan, Lisa V.; Eydlin, Olga; Piskoun, Boris; Kline, Richard P; Recio-Pinto, Esperanza; Rosenberg, Andrew D; Blanck, Thomas JJ; Xu, Fang

    2013-01-01

    Background Neuraxial local anesthetics may have neurological complications thought to be due to neurotoxicity. A primary site of action for local anesthetics is the dorsal root ganglia (DRG) neuron. Physiologic differences have been noted between young and adult DRG neurons; hence, we examined whether there were differences in lidocaine-induced changes in calcium and lidocaine toxicity in neonatal and adult rat DRG neurons. Methods DRG neurons were cultured from postnatal day 7 (P7) and adult rats. Lidocaine-induced changes in cytosolic calcium were examined with the calcium indicator Fluo-4. Cells were incubated with varying concentrations of lidocaine and examined for viability using calcein AM and ethidium homodimer-1 staining. Live imaging of caspase-3/7 activation was performed after incubation with lidocaine. Results The mean KCl-induced calcium transient was greater in P7 neurons (p lidocaine significantly inhibited KCl-induced calcium responses in both ages (p lidocaine, KCl-induced calcium transients in both ages became more homogeneous but remained different between the groups. Interestingly cell viability was decreased by lidocaine in a dose-dependent manner similarly in both ages. Lidocaine treatment also activated caspase-3/7 in a dose- and time-dependent manner similarly in both ages. Conclusions Despite physiological differences in P7 and adult DRG neurons, lidocaine cytotoxicity is similar in P7 and adult DRG neurons in vitro. Differences in lidocaine- and KCl-evoked calcium responses suggest the similarity in lidocaine cytotoxicity involves other actions in addition to lidocaine-evoked effects on cytosolic calcium responses. PMID:23851347

  7. Shp-1 dephosphorylates TRPV1 in dorsal root ganglion neurons and alleviates CFA-induced inflammatory pain in rats.

    Science.gov (United States)

    Xiao, Xing; Zhao, Xiao-Tao; Xu, Ling-Chi; Yue, Lu-Peng; Liu, Feng-Yu; Cai, Jie; Liao, Fei-Fei; Kong, Jin-Ge; Xing, Guo-Gang; Yi, Ming; Wan, You

    2015-04-01

    Transient receptor potential vanilloid 1 (TRPV1) receptors are expressed in nociceptive neurons of rat dorsal root ganglions (DRGs) and mediate inflammatory pain. Nonspecific inhibition of protein-tyrosine phosphatases (PTPs) increases the tyrosine phosphorylation of TRPV1 and sensitizes TRPV1. However, less is known about tyrosine phosphorylation's implication in inflammatory pain, compared with that of serine/threonine phosphorylation. Src homology 2 domain-containing tyrosine phosphatase 1 (Shp-1) is a key phosphatase dephosphorylating TRPV1. In this study, we reported that Shp-1 colocalized with and bound to TRPV1 in nociceptive DRG neurons. Shp-1 inhibitors, including sodium stibogluconate and PTP inhibitor III, sensitized TRPV1 in cultured DRG neurons. In naive rats, intrathecal injection of Shp-1 inhibitors increased both TRPV1 and tyrosine-phosphorylated TRPV1 in DRGs and induced thermal hyperalgesia, which was abolished by pretreatment with TRPV1 antagonists capsazepine, BCTC, or AMG9810. Complete Freund's adjuvant (CFA)-induced inflammatory pain in rats significantly increased the expression of Shp-1, TRPV1, and tyrosine-phosphorylated TRPV1, as well as the colocalization of Shp-1 and TRPV1 in DRGs. Intrathecal injection of sodium stibogluconate aggravated CFA-induced inflammatory pain, whereas Shp-1 overexpression in DRG neurons alleviated it. These results suggested that Shp-1 dephosphorylated and inhibited TRPV1 in DRG neurons, contributing to maintain thermal nociceptive thresholds in normal rats, and as a compensatory mechanism, Shp-1 increased in DRGs of rats with CFA-induced inflammatory pain, which was involved in protecting against excessive thermal hyperalgesia.

  8. Prostaglandin E2 potentiation of P2X3 receptor mediated currents in dorsal root ganglion neurons

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    Huang Li-Yen

    2007-08-01

    Full Text Available Abstract Prostaglandin E2 (PGE2 is a well-known inflammatory mediator that enhances the excitability of DRG neurons. Homomeric P2X3 and heteromeric P2X2/3 receptors are abundantly expressed in dorsal root ganglia (DRG neurons and participate in the transmission of nociceptive signals. The interaction between PGE2 and P2X3 receptors has not been well delineated. We studied the actions of PGE2 on ATP-activated currents in dissociated DRG neurons under voltage-clamp conditions. PGE2 had no effects on P2X2/3 receptor-mediated responses, but significantly potentiated fast-inactivating ATP currents mediated by homomeric P2X3 receptors. PGE2 exerted its action by activating EP3 receptors. To study the mechanism underlying the action of PGE2, we found that the adenylyl cyclase activator, forskolin and the membrane-permeable cAMP analogue, 8-Br-cAMP increased ATP currents, mimicking the effect of PGE2. In addition, forskolin occluded the enhancement produced by PGE2. The protein kinase A (PKA inhibitors, H89 and PKA-I blocked the PGE2 effect. In contrast, the PKC inhibitor, bisindolymaleimide (Bis did not change the potentiating action of PGE2. We further showed that PGE2 enhanced α,β-meATP-induced allodynia and hyperalgesia and the enhancement was blocked by H89. These observations suggest that PGE2 binds to EP3 receptors, resulting in the activation of cAMP/PKA signaling pathway and leading to an enhancement of P2X3 homomeric receptor-mediated ATP responses in DRG neurons.

  9. Quantitative Analysis of Rat Dorsal Root Ganglion Neurons Cultured on Microelectrode Arrays Based on Fluorescence Microscopy Image Processing.

    Science.gov (United States)

    Mari, João Fernando; Saito, José Hiroki; Neves, Amanda Ferreira; Lotufo, Celina Monteiro da Cruz; Destro-Filho, João-Batista; Nicoletti, Maria do Carmo

    2015-12-01

    Microelectrode Arrays (MEA) are devices for long term electrophysiological recording of extracellular spontaneous or evocated activities on in vitro neuron culture. This work proposes and develops a framework for quantitative and morphological analysis of neuron cultures on MEAs, by processing their corresponding images, acquired by fluorescence microscopy. The neurons are segmented from the fluorescence channel images using a combination of segmentation by thresholding, watershed transform, and object classification. The positioning of microelectrodes is obtained from the transmitted light channel images using the circular Hough transform. The proposed method was applied to images of dissociated culture of rat dorsal root ganglion (DRG) neuronal cells. The morphological and topological quantitative analysis carried out produced information regarding the state of culture, such as population count, neuron-to-neuron and neuron-to-microelectrode distances, soma morphologies, neuron sizes, neuron and microelectrode spatial distributions. Most of the analysis of microscopy images taken from neuronal cultures on MEA only consider simple qualitative analysis. Also, the proposed framework aims to standardize the image processing and to compute quantitative useful measures for integrated image-signal studies and further computational simulations. As results show, the implemented microelectrode identification method is robust and so are the implemented neuron segmentation and classification one (with a correct segmentation rate up to 84%). The quantitative information retrieved by the method is highly relevant to assist the integrated signal-image study of recorded electrophysiological signals as well as the physical aspects of the neuron culture on MEA. Although the experiments deal with DRG cell images, cortical and hippocampal cell images could also be processed with small adjustments in the image processing parameter estimation.

  10. Effects of selenium on calcium signaling and apoptosis in rat dorsal root ganglion neurons induced by oxidative stress.

    Science.gov (United States)

    Uğuz, Abdülhadi Cihangir; Nazıroğlu, Mustafa

    2012-08-01

    Ca(2+) is well known for its role as crucial second messenger in modulating many cellular physiological functions, Ca(2+) overload is detrimental to cellular function and may present as an important cause of cellular oxidative stress generation and apoptosis. The aim of this study is to investigate the effects of selenium on lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GSH-Px), cytosolic Ca(2+) release, cell viability (MTT) and apoptosis values in dorsal root ganglion (DRG) sensory neurons of rats. DRG cells were divided into four groups namely control, H(2)O(2) (as a model substance used as a paradigm for oxidative stress), selenium, selenium + H(2)O(2). Moderate doses and times of H(2)O(2) and selenium were determined by MTT test. Cells were preterated 200 nM selenium for 30 h before incubatation with 1 μM H(2)O(2) for 2 h. Lipid peroxidation levels were lower in the control, selenium, selenium + H(2)O(2) groups than in the H(2)O(2) group. GSH-Px activities were higher in the selenium groups than in the H(2)O(2) group. GSH levels were higher in the control, selenium, selenium + H(2)O(2) groups than in the H(2)O(2) group. Cytosolic Ca(2+) release was higher in the H(2)O(2) group than in the control, selenium, selenium + H(2)O(2) groups. Cytosolic Ca(2+) release was lower in the selenium + H(2)O(2) group than in the H(2)O(2). In conclusion, the present study demonstrates that selenium induced protective effects on oxidative stress, [Ca(2+)](c) release and apoptosis in DRG cells. Since selenium deficiency is a common feature of oxidative stress-induced neurological diseases of sensory neurons, our findings are relevant to the etiology of pathology in oxidative stress-induced neurological diseases of the DRG neurons.

  11. Altered expression of sodium channel distribution in the dorsal root ganglion after gradual elongation of rat sciatic nerves.

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    Ohno, Katsunori; Yokota, Atsushi; Hirofuji, Shinji; Kanbara, Kiyoto; Ohtsuka, Hisashi; Kinoshita, Mitsuo

    2010-04-01

    To elucidate the pathophysiological mechanisms underlying chronic nerve-stretch injury, we gradually lengthened rat femurs by 15 mm at the rate of 0.5 mm/day (group L, n = 13). The control groups comprised sham-operated (group S, n = 10) and naive (group N, n = 8) rats. Immediately after the lengthening, we performed a conduction study on their sciatic nerves and harvested samples. Electrophysiological and histological analyses showed mild conduction slowing and axonal degeneration of unmyelinated fibers in group L rats. Altered mRNA expression of the voltage-gated sodium channels in the dorsal root ganglion was also observed. Tetrodotoxin-resistant (TTX-R) sodium-channel Nav1.8 mRNA expression was significantly decreased and TTX-R sodium-channel Nav1.9 mRNA expression showed a tendency to decrease when compared with the mRNA expressions in the control groups. However, tetrodotoxin-sensitive (TTX-S) sodium-channel Nav1.3 mRNA expression remained unaltered. The immunohistochemical alteration of Nav1.8 protein expression was parallel to the results of the mRNA expression. Previous studies involving neuropathic states have suggested that pain/paresthesia is modulated by a subset of sodium channels, including downregulation and/or upregulation of TTX-R and TTX-S sodium channels, respectively. Our findings indicate that Nav1.8 downregulation may be one of the pathophysiological mechanisms involved in limb lengthening-induced neuropathy.

  12. Expression of the immunoglobulin superfamily cell adhesion molecules in the developing spinal cord and dorsal root ganglion.

    Science.gov (United States)

    Gu, Zirong; Imai, Fumiyasu; Kim, In Jung; Fujita, Hiroko; Katayama, Kei ichi; Mori, Kensaku; Yoshihara, Yoshihiro; Yoshida, Yutaka

    2015-01-01

    Cell adhesion molecules belonging to the immunoglobulin superfamily (IgSF) control synaptic specificity through hetero- or homophilic interactions in different regions of the nervous system. In the developing spinal cord, monosynaptic connections of exquisite specificity form between proprioceptive sensory neurons and motor neurons, however, it is not known whether IgSF molecules participate in regulating this process. To determine whether IgSF molecules influence the establishment of synaptic specificity in sensory-motor circuits, we examined the expression of 157 IgSF genes in the developing dorsal root ganglion (DRG) and spinal cord by in situ hybridization assays. We find that many IgSF genes are expressed by sensory and motor neurons in the mouse developing DRG and spinal cord. For instance, Alcam, Mcam, and Ocam are expressed by a subset of motor neurons in the ventral spinal cord. Further analyses show that Ocam is expressed by obturator but not quadriceps motor neurons, suggesting that Ocam may regulate sensory-motor specificity in these sensory-motor reflex arcs. Electrophysiological analysis shows no obvious defects in synaptic specificity of monosynaptic sensory-motor connections involving obturator and quadriceps motor neurons in Ocam mutant mice. Since a subset of Ocam+ motor neurons also express Alcam, Alcam or other functionally redundant IgSF molecules may compensate for Ocam in controlling sensory-motor specificity. Taken together, these results reveal that IgSF molecules are broadly expressed by sensory and motor neurons during development, and that Ocam and other IgSF molecules may have redundant functions in controlling the specificity of sensory-motor circuits.

  13. Expression of the immunoglobulin superfamily cell adhesion molecules in the developing spinal cord and dorsal root ganglion.

    Directory of Open Access Journals (Sweden)

    Zirong Gu

    Full Text Available Cell adhesion molecules belonging to the immunoglobulin superfamily (IgSF control synaptic specificity through hetero- or homophilic interactions in different regions of the nervous system. In the developing spinal cord, monosynaptic connections of exquisite specificity form between proprioceptive sensory neurons and motor neurons, however, it is not known whether IgSF molecules participate in regulating this process. To determine whether IgSF molecules influence the establishment of synaptic specificity in sensory-motor circuits, we examined the expression of 157 IgSF genes in the developing dorsal root ganglion (DRG and spinal cord by in situ hybridization assays. We find that many IgSF genes are expressed by sensory and motor neurons in the mouse developing DRG and spinal cord. For instance, Alcam, Mcam, and Ocam are expressed by a subset of motor neurons in the ventral spinal cord. Further analyses show that Ocam is expressed by obturator but not quadriceps motor neurons, suggesting that Ocam may regulate sensory-motor specificity in these sensory-motor reflex arcs. Electrophysiological analysis shows no obvious defects in synaptic specificity of monosynaptic sensory-motor connections involving obturator and quadriceps motor neurons in Ocam mutant mice. Since a subset of Ocam+ motor neurons also express Alcam, Alcam or other functionally redundant IgSF molecules may compensate for Ocam in controlling sensory-motor specificity. Taken together, these results reveal that IgSF molecules are broadly expressed by sensory and motor neurons during development, and that Ocam and other IgSF molecules may have redundant functions in controlling the specificity of sensory-motor circuits.

  14. Reactive species modify NaV1.8 channels and affect action potentials in murine dorsal root ganglion neurons.

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    Schink, Martin; Leipold, Enrico; Schirmeyer, Jana; Schönherr, Roland; Hoshi, Toshinori; Heinemann, Stefan H

    2016-01-01

    Dorsal root ganglion (DRG) neurons are important relay stations between the periphery and the central nervous system and are essential for somatosensory signaling. Reactive species are produced in a variety of physiological and pathophysiological conditions and are known to alter electric signaling. Here we studied the influence of reactive species on the electrical properties of DRG neurons from mice with the whole-cell patch-clamp method. Even mild stress induced by either low concentrations of chloramine-T (10 μM) or low-intensity blue light irradiation profoundly diminished action potential frequency but prolonged single action potentials in wild-type neurons. The impact on evoked action potentials was much smaller in neurons deficient of the tetrodotoxin (TTX)-resistant voltage-gated sodium channel NaV1.8 (NaV1.8(-/-)), the channel most important for the action potential upstroke in DRG neurons. Low concentrations of chloramine-T caused a significant reduction of NaV1.8 peak current and, at higher concentrations, progressively slowed down inactivation. Blue light had a smaller effect on amplitude but slowed down NaV1.8 channel inactivation. The observed effects were less apparent for TTX-sensitive NaV channels. NaV1.8 is an important reactive-species-sensitive component in the electrical signaling of DRG neurons, potentially giving rise to loss-of-function and gain-of-function phenomena depending on the type of reactive species and their effective concentration and time of exposure.

  15. Dorsal striatum is necessary for stimulus-value but not action-value learning in humans.

    Science.gov (United States)

    Vo, Khoi; Rutledge, Robb B; Chatterjee, Anjan; Kable, Joseph W

    2014-12-01

    Several lines of evidence implicate the striatum in learning from experience on the basis of positive and negative feedback. However, the necessity of the striatum for such learning has been difficult to demonstrate in humans, because brain damage is rarely restricted to this structure. Here we test a rare individual with widespread bilateral damage restricted to the dorsal striatum. His performance was impaired and not significantly different from chance on several classic learning tasks, consistent with current theories regarding the role of the striatum. However, he also exhibited remarkably intact performance on a different subset of learning paradigms. The tasks he could perform can all be solved by learning the value of actions, while those he could not perform can only be solved by learning the value of stimuli. Although dorsal striatum is often thought to play a specific role in action-value learning, we find surprisingly that dorsal striatum is necessary for stimulus-value but not action-value learning in humans. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Global diffuse distribution in the brain and efficient gene delivery to the dorsal root ganglia by intrathecal injection of adeno-associated viral vector serotype 1.

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    Iwamoto, Naotaka; Watanabe, Atsushi; Yamamoto, Motoko; Miyake, Noriko; Kurai, Toshiyuki; Teramoto, Akira; Shimada, Takashi

    2009-06-01

    The success of gene therapy for inherited neurodegenerative diseases such as metachromatic leukodystrophy (MLD) depends on the development of efficient gene delivery throughout the brain guarded by the blood-brain barrier and achieves distribution of the deficient enzyme throughout the brain. Direct injection of viral vector into the brain parenchyma is too invasive and may not be sufficient to treat the entire brain. As an alternative approach, we examined the feasibility of intrathecal (IT) injection of adeno-associated viral vector serotype 1 (AAV1). AAV1 vector expressing arylsulfatase A (ASA) and green fluorescence protein (GFP) was intrathecally injected into ASA knockout MLD model mice. Expression of GFP was assessed by fluorescence microscopy and immunohistochemical methods, whereas the concentration of ASA was determined by a quantitative enzyme-linked immunosorbent assay. Broad distribution of GFP expression was seen throughout the brain after IT injection of AAV1 vector. In addition, a large number of nerve fibers in the dorsal spinal cord and many neural cell bodies in the dorsal root ganglia were efficiently transduced. Widespread distribution of ASA activity and a significant reduction of sulfatide content were confirmed in treated MLD model mice. IT injection of AAV1 vector is a useful and non-invasive method for widespread gene delivery to the brain and dorsal root ganglia. (c) 2009 John Wiley & Sons, Ltd.

  17. Varicella-zoster virus glycoprotein I is essential for spread in dorsal root ganglia and facilitates axonal localization of structural virion components in neuronal cultures.

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    Christensen, Jenna; Steain, Megan; Slobedman, Barry; Abendroth, Allison

    2013-12-01

    Neurons of the sensory ganglia are the major site of varicella-zoster virus (VZV) latency and may undergo productive infection during reactivation. Although the VZV glycoprotein E/glycoprotein I (gE/gI) complex is known to be critical for neurovirulence, few studies have assessed the roles of these proteins during infection of dorsal root ganglia (DRG) due to the high human specificity of the virus. Here, we show that the VZV glycoprotein I gene is an important neurotropic gene responsible for mediating the spread of virus in neuronal cultures and explanted DRG. Inoculation of differentiated SH-SY5Y neuronal cell cultures with a VZV gI gene deletion strain (VZV rOkaΔgI) showed a large reduction in the percentage of cells infected and significantly smaller plaque sizes in a comparison with cultures infected with the parental strain (VZV rOka). In contrast, VZV rOkaΔgI was not significantly attenuated in fibroblast cultures, demonstrating a cell type-specific role for VZV gI. Analysis of rOkaΔgI protein localization by immunofluorescent staining revealed aberrant localization of viral glycoprotein and capsid proteins, with little or no staining present in the axons of differentiated SH-SY5Y cells infected with rOkaΔgI, yet axonal vesicle trafficking was not impaired. Further studies utilizing explanted human DRG indicated that VZV gI is required for the spread of virus within DRG. These data demonstrate a role for VZV gI in the cell-to-cell spread of virus during productive replication in neuronal cells and a role in facilitating the access of virion components to axons.

  18. Pharmacological fractionation of tetrodotoxin-sensitive sodium currents in rat dorsal root ganglion neurons by μ-conotoxins.

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    Zhang, Min-Min; Wilson, Michael J; Gajewiak, Joanna; Rivier, Jean E; Bulaj, Grzegorz; Olivera, Baldomero M; Yoshikami, Doju

    2013-05-01

    Adult rat dorsal root ganglion (DRG) neurons normally express transcripts for five isoforms of the α-subunit of voltage-gated sodium channels: NaV 1.1, 1.6, 1.7, 1.8 and 1.9. Tetrodotoxin (TTX) readily blocks all but NaV 1.8 and 1.9, and pharmacological agents that discriminate among the TTX-sensitive NaV 1-isoforms are scarce. Recently, we used the activity profile of a panel of μ-conotoxins in blocking cloned rodent NaV 1-isoforms expressed in Xenopus laevis oocytes to conclude that action potentials of A- and C-fibres in rat sciatic nerve were, respectively, mediated primarily by NaV 1.6 and NaV 1.7. We used three μ-conotoxins, μ-TIIIA, μ-PIIIA and μ-SmIIIA, applied individually and in combinations, to pharmacologically differentiate the TTX-sensitive INa of voltage-clamped neurons acutely dissociated from adult rat DRG. We examined only small and large neurons whose respective INa were >50% and >80% TTX-sensitive. In both small and large neurons, the ability of the toxins to block TTX-sensitive INa was μ-TIIIA NaV 1-isoforms, co-expressed with various NaV β-subunits in X. laevis oocytes, were consistent: NaV 1.1, 1.6 and 1.7 could account for all of the TTX-sensitive INa , with NaV 1.1 NaV 1.6 NaV 1.7 for small neurons and NaV 1.7 NaV 1.1 NaV 1.6 for large neurons. Combinations of μ-conotoxins can be used to determine the probable NaV 1-isoforms underlying the INa in DRG neurons. Preliminary experiments with sympathetic neurons suggest that this approach is extendable to other neurons. © 2013 The Authors. British Journal of Pharmacology © 2013 The British Pharmacological Society.

  19. [Effects of Electroacupuncture on Activities of Satellite Glial Cells of Dorsal Root Ganglia in Rats with Neck Incision Pain].

    Science.gov (United States)

    Qiao, Li-Na; Tan, Lian-Hong; Yang, Jiao-Jiao; Gao, Qiao-Ling; Zhu, Jiang; Rong, Pei-Jing; Zhu, Bing; Yang, Yong-Sheng; Liu, Jun-Ling

    2017-08-25

    To observe the effect of electroacupuncture (EA) stimulation of "Futu"(LI 18), etc. on activities of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) in rats with neck-incision pain so as to explore its mechanism underlying reduction of post-surgical pain of thyroidectomy. Male SD rats were randomly divided into control, model, EA-Futu (LI 18), EA-Hegu (LI 4)-Neiguan (PC 6), and EA-Zusanli (ST 36)-Yanglingquan (GB 34) groups, with 20 rats in each group. The neck-incision pain model was established by making a longitudinal incision and repeated mechanical stimulation. In the EA-LI 18, EA-LI 4-PC 6 and EA-ST 36-GB 34 groups, EA stimulation was administrated for 30 min, once a day,continuously for 3 days. The thermal pain threshold (PT) of the neck-incision region was detected. The immunoactivity of glial fibrillary acidic protein (GFAP,a specific marker for SGCs) and connexin 43 (Cx 43) of DRGs (C 2-C 6) was determined by fluorescent immunohistochemistry. The expression levels of GFAP, IL-1 β, IL-6, and TNF-α mRNAs were determined by quantitative Real-time PCR, and the contents of IL-1 β,IL-6,TNF-α assayed by enzyme linked immunosorbent assay (ELISA) and the expression of Cx 43 protein was detected by Western blot. After EA intervention at LI 18 and LI 4-PC 6 (but not ST 36-GB 34), neck incision-induced reduction of the thermal PT was obviously prolonged in comparison with the model group (PGB 34 group except the down-regulated IL-1 β and TNF-α mRNAs, in the contents of IL-1 β and TNF-α of the EA-LI 4-PC 6 group, and in the IL-6 content of the EA-LI 18 group (P>0.05). EA stimulation of LI 18 and LI 4-PC 6 can significantly suppress pain reaction of neck incision in the rat, which is closely associated with its effects in down-regulating the activity of SGCs, decreasing the release of pro-inflammatory cytokines and in weakening the expression of Cx 43 in the cervical DRGs.

  20. Kv4 channels underlie the subthreshold-operating A-type K+-current in nociceptive dorsal root ganglion neurons

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    Thanawath R Na Phuket

    2009-07-01

    Full Text Available The dorsal root ganglion (DRG contains heterogeneous populations of sensory neurons including primary nociceptive neurons and C-fibers implicated in pain signaling.  Recent studies have demonstrated DRG hyperexcitability associated with downregulation of A-type K+ channels; however, the molecular correlate of the corresponding A-type K+ current (IA has remained hypothetical.  Kv4 channels may underlie the IA in DRG neurons.  We combined electrophysiology, molecular biology (whole-tissue and single-cell RT-PCR and immunohistochemistry to investigate the molecular basis of the IA in acutely dissociated DRG neurons from 7-8 day-old rats.  Whole-cell recordings demonstrate a robust tetraethylammonium-resistant (20 mM and 4-aminopyridine-sensitive (5 mM IA.  Matching Kv4 channel properties, activation and inactivation of this IA occur in the subthreshold range of membrane potentials and the rate of recovery from inactivation is rapid and voltage-dependent.  Among Kv4 transcripts, the DRG expresses significant levels of Kv4.1 and Kv4.3 mRNAs.  Also, single small-medium diameter DRG neurons (~30 mm exhibit correlated frequent expression of mRNAs encoding Kv4.1 and Nav1.8, a known nociceptor marker.  In contrast, the expressions of Kv1.4 and Kv4.2 mRNAs at the whole-tissue and single-cell levels are relatively low and infrequent.  Kv4 protein expression in nociceptive DRG neurons was confirmed by immunohistochemistry, which demonstrates colocalization of Kv4.3 and Nav1.8, and negligible expression of Kv4.2.  Furthermore, specific dominant-negative suppression and overexpression strategies confirmed the contribution of Kv4 channels to IA in DRG neurons.  Contrasting the expression patterns of Kv4 channels in the central and peripheral nervous systems, we discuss possible functional roles of these channels in primary sensory neurons.

  1. Differential expression of ATP7A, ATP7B and CTR1 in adult rat dorsal root ganglion tissue

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    Ip Virginia

    2010-09-01

    Full Text Available Abstract Background ATP7A, ATP7B and CTR1 are metal transporting proteins that control the cellular disposition of copper and platinum drugs, but their expression in dorsal root ganglion (DRG tissue and their role in platinum-induced neurotoxicity are unknown. To investigate the DRG expression of ATP7A, ATP7B and CTR1, lumbar DRG and reference tissues were collected for real time quantitative PCR, RT-PCR, immunohistochemistry and Western blot analysis from healthy control adult rats or from animals treated with intraperitoneal oxaliplatin (1.85 mg/kg or drug vehicle twice weekly for 8 weeks. Results In DRG tissue from healthy control animals, ATP7A mRNA was clearly detectable at levels similar to those found in the brain and spinal cord, and intense ATP7A immunoreactivity was localised to the cytoplasm of cell bodies of smaller DRG neurons without staining of satellite cells, nerve fibres or co-localisation with phosphorylated heavy neurofilament subunit (pNF-H. High levels of CTR1 mRNA were detected in all tissues from healthy control animals, and strong CTR1 immunoreactivity was associated with plasma membranes and vesicular cytoplasmic structures of the cell bodies of larger-sized DRG neurons without co-localization with ATP7A. DRG neurons with strong expression of ATP7A or CTR1 had distinct cell body size profiles with minimal overlap between them. Oxaliplatin treatment did not alter the size profile of strongly ATP7A-immunoreactive neurons but significantly reduced the size profile of strongly CTR1-immunoreactive neurons. ATP7B mRNA was barely detectable, and no specific immunoreactivity for ATP7B was found, in DRG tissue from healthy control animals. Conclusions In conclusion, adult rat DRG tissue exhibits a specific pattern of expression of copper transporters with distinct subsets of peripheral sensory neurons intensely expressing either ATP7A or CTR1, but not both or ATP7B. The neuron subtype-specific and largely non

  2. The distribution of kisspeptin and its receptor GPR54 in rat dorsal root ganglion and up-regulation of its expression after CFA injection.

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    Mi, Wen-Li; Mao-Ying, Qi-Liang; Liu, Qiong; Wang, Xiao-Wei; Li, Xiu; Wang, Yan-Qing; Wu, Gen-Cheng

    2009-03-16

    Kisspeptin/GPR54 system plays a crucial role in the control of puberty onset and reproductive function. In the present study, we gave the first report that kisspeptin and GPR54 were expressed in the small- to large-sized neurons, and co-localized with Bandeiraea simplicifolia isolectin B4 (IB4), calcitonin-gene-related peptide (CGRP) and neurofilament 200 (NF200) in the L4/5 dorsal root ganglion (DRG) of naïve rats, detected by the double immunofluorescent staining. Interestingly, a marked elevation in the levels of KiSS-1 and GPR54 mRNA as well as protein was observed in the spinal dorsal horn and DRG 4 and 14 days following intra-articular injection of complete Freund's adjuvant (CFA), indicating a possible involvement of the kisspeptin/GPR54 system in chronic inflammatory pain.

  3. Effects of sciatic nerve transection on glucose uptake in the presence and absence of lactate in the frog dorsal root ganglia and spinal cord

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    F Rigon

    Full Text Available Frogs have been used as an alternative model to study pain mechanisms because the simplicity of their nervous tissue and the phylogenetic aspect of this question. One of these models is the sciatic nerve transection (SNT, which mimics the clinical symptoms of “phantom limb”, a condition that arises in humans after amputation or transverse spinal lesions. In mammals, the SNT increases glucose metabolism in the central nervous system, and the lactate generated appears to serve as an energy source for nerve cells. An answerable question is whether there is elevated glucose uptake in the dorsal root ganglia (DRG after peripheral axotomy. As glucose is the major energy substrate for frog nervous tissue, and these animals accumulate lactic acid under some conditions, bullfrogs Lithobates catesbeianus were used to demonstrate the effect of SNT on DRG and spinal cord 1-[14C] 2-deoxy-D-glucose (14C-2-DG uptake in the presence and absence of lactate. We also investigated the effect of this condition on the formation of 14CO2 from 14C-glucose and 14C-L-lactate, and plasmatic glucose and lactate levels. The 3-O-[14C] methyl-D-glucose (14C-3-OMG uptake was used to demonstrate the steady-state tissue/medium glucose distribution ratio under these conditions. Three days after SNT, 14C-2-DG uptake increased, but 14C-3-OMG uptake remained steady. The increase in 14C-2-DG uptake was lower when lactate was added to the incubation medium. No change was found in glucose and lactate oxidation after SNT, but lactate and glucose levels in the blood were reduced. Thus, our results showed that SNT increased the glucose metabolism in the frog DRG and spinal cord. The effect of lactate on this uptake suggests that glucose is used in glycolytic pathways after SNT.

  4. Direct effects of HIV-1 Tat on excitability and survival of primary dorsal root ganglion neurons: possible contribution to HIV-1-associated pain.

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    Xianxun Chi

    Full Text Available The vast majority of people living with human immunodeficiency virus type 1 (HIV-1 have pain syndrome, which has a significant impact on their quality of life. The underlying causes of HIV-1-associated pain are not likely attributable to direct viral infection of the nervous system due to the lack of evidence of neuronal infection by HIV-1. However, HIV-1 proteins are possibly involved as they have been implicated in neuronal damage and death. The current study assesses the direct effects of HIV-1 Tat, one of potent neurotoxic viral proteins released from HIV-1-infected cells, on the excitability and survival of rat primary dorsal root ganglion (DRG neurons. We demonstrated that HIV-1 Tat triggered rapid and sustained enhancement of the excitability of small-diameter rat primary DRG neurons, which was accompanied by marked reductions in the rheobase and resting membrane potential (RMP, and an increase in the resistance at threshold (R(Th. Such Tat-induced DRG hyperexcitability may be a consequence of the inhibition of cyclin-dependent kinase 5 (Cdk5 activity. Tat rapidly inhibited Cdk5 kinase activity and mRNA production, and roscovitine, a well-known Cdk5 inhibitor, induced a very similar pattern of DRG hyperexcitability. Indeed, pre-application of Tat prevented roscovitine from having additional effects on the RMP and action potentials (APs of DRGs. However, Tat-mediated actions on the rheobase and R(Th were accelerated by roscovitine. These results suggest that Tat-mediated changes in DRG excitability are partly facilitated by Cdk5 inhibition. In addition, Cdk5 is most abundant in DRG neurons and participates in the regulation of pain signaling. We also demonstrated that HIV-1 Tat markedly induced apoptosis of primary DRG neurons after exposure for longer than 48 h. Together, this work indicates that HIV-1 proteins are capable of producing pain signaling through direct actions on excitability and survival of sensory neurons.

  5. Propofol Modulates Agonist-induced Transient Receptor Potential Vanilloid Subtype-1 Receptor Desensitization via a Protein Kinase Cε-dependent Pathway in Mouse Dorsal Root Ganglion Sensory Neurons

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    Wickley, Peter J.; Yuge, Ryo; Russell, Mary S.; Zhang, Hongyu; Sulak, Michael A.; Damron, Derek S.

    2011-01-01

    Background The activity of transient receptor potential vanilloid subtype-1 (TRPV1) receptors, key nociceptive transducers in dorsal root ganglion sensory neurons, is enhanced by protein kinase C ε (PKCε) activation. The intravenous anesthetic propofol has been shown to activate PKCε. Our objectives were to examine whether propofol modulates TRPV1 function in dorsal root ganglion neurons via activation of PKCε. Methods Lumbar dorsal root ganglion neurons from wild-type and PKCε-null mice were isolated and cultured for 24 h. Intracellular free Ca2+ concentration was measured in neurons by using fura-2 acetoxymethyl ester. The duration of pain-associated behaviors was also assessed. Phosphorylation of PKCε and TRPV1 and the cellular translocation of PKCε from cytosol to membrane compartments were assessed by immunoblot analysis. Results In wild-type neurons, repeated stimulation with capsaicin (100 nM) progressively decreased the transient rise in intracellular free Ca2+ concentration. After desensitization, exposure to propofol rescued the Ca2+ response. The resensitizing effect of propofol was absent in neurons obtained from PKCε-null mice. Moreover, the capsaicin-induced desensitization of TRPV1 was markedly attenuated in the presence of propofol in neurons from wild-type mice but not in neurons from PKCε-null mice. Propofol also prolonged the duration of agonist-induced pain associated behaviors in wild-type mice. In addition, propofol increased phosphorylation of PKCε as well as TRPV1 and stimulated translocation of PKCε from cytosolic to membrane fraction. Discussion Our results indicate that propofol modulates TRPV1 sensitivity to capsaicin and that this most likely occurs through a PKCε-mediated phosphorylation of TRPV1. PMID:20808213

  6. Vasopressin immunoreactive fibers and neurons in the dorsal pontine tegmentum of the rat, monkey and human.

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    Caffé, A R; Holstege, J C; van Leeuwen, F W

    1991-01-01

    It is now well established that extensive extrahypothalamic vasopressin (VP) systems exist in the rat, monkey and human brain. There are marked differences between species, but in each case VP nuclei provide dense afferents to the dorsal pontine tegmentum. Here VP may play a role in the mechanisms exerted by the locus coeruleus (LC) neurons, possibly both as a neurotransmitter and as a neuromodulator. Although we are aware of some properties of VP systems, e.g., gonadal steroid dependency in the rat, major gaps characterize our knowledge of its anatomy. With regard to the interaction of VP with the LC in the brainstem of mammals some of the questions which stand out are: (1) Is VP really being biosynthesized and transported by LC cells and, if not, what is its function within these cells? (2) Is there a structural difference between male and female LC neurons in the rat as a consequence of the sex-dimorphic VP innervation? (3) What is the origin of VP afferents in the dorsal pontine tegmentum of the (non)human primate and are these afferents also controlled by gonadal steroids? Research strategies to answer these questions will provide us with information to resolve some of the current inconsistencies about the anatomy and the function of the VP and LC systems in the brain.

  7. Regulation of the Spontaneous Augmentation of Na_V1.9 in Mouse Dorsal Root Ganglion Neurons : Effect of PKA and PKC Pathways

    OpenAIRE

    Nobukuni Ogata; Noriko Uryu; Taixing Zheng; Jun-ichi Kakimura

    2010-01-01

    Sensory neurons in the dorsal root ganglion express two kinds of tetrodotoxin resistant (TTX-R) isoforms of voltage-gated sodium channels, NaV1.8 and NaV1.9. These isoforms play key roles in the pathophysiology of chronic pain. Of special interest is NaV1.9: our previous studies revealed a unique property of the NaV1.9 current, i.e., the NaV1.9 current shows a gradual and notable up-regulation of the peak amplitude during recording (“spontaneous augmentation of NaV1.9”). However, the mechanis...

  8. The roots and branches of human altruism.

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    Hay, Dale F

    2009-08-01

    The authors' rigorous and ingenious programme of work documents young humans' capacity for prosocial action (Warneken & Tomasello, 2009). Their laboratory findings are corroborated by centuries of observational data, spanning cultures, and historical epochs. Two general questions are raised. Firstly, what are the rules of evidence needed in using comparative data to make claims about the evolution of human social behaviours? Secondly, what ontogenetic processes contribute to the transformation of toddlers' helpfulness into mature, cognitively informed and rule-governed altruism? These findings alone do not provide complete evidence for the phylogenetic roots of altruism. I argue that selective pressures in human evolution have favoured sociability, which could lead to aggression or altruism, depending on context and the nature of the rearing environment. Any social behaviour shown in infancy may have multiple functions, at phylogenetic, ontogenetic and episodic levels of analysis.

  9. Human cerebrocortical potentials evoked by stimulation of the dorsal nerve of the penis.

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    Bradley, W E; Farrell, D F; Ojemann, G A

    1998-01-01

    Cortical evoked potentials resulting from stimulation of the dorsal nerve of the penis (DNP) provide a unique opportunity to document the cortical localization of sexual sensory representation in man. The DNP supplies sensory axons to the major portion of the human phallus, including the penile shaft and glans. Animal and human studies indicate that this nerve plays a crucial role in erection and ejaculation. Direct cortical evoked responses to DNP electrical stimulation were recorded in patients undergoing preoperative evaluation for resection of epileptic foci. These studies provided evidence that the primary sensory cortex contains a large area of cortex devoted to the afferent fibers of the DNP and that the sensory field is in a different location than previously described. The location and distribution of this response indicated the need for revision of the traditional concept of the sensory cortical homunculus.

  10. Cytotoxic effect of commercially available methylprednisolone acetate with and without reduced preservatives on dorsal root ganglion sensory neurons in rats.

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    Knezevic, Nebojsa Nick; Candido, Kenneth D; Cokic, Ivan; Krbanjevic, Aleksandar; Berth, Sarah L; Knezevic, Ivana

    2014-01-01

    Epidural and intrathecal injections of methylprednisolone acetate (MPA) have become the most commonly performed interventional procedures in the United States and worldwide in the last 2 decades. However neuraxial MPA injection has been dogged by controversy regarding the presence of different additives used in commercially prepared glucocorticoids. We previously showed that MPA could be rendered 85% free of polyethylene glycol (PEG) by a simple physical separation of elements in the suspension. The objective of the present study was to explore a possible cytotoxic effect of commercially available MPA (with intact or reduced preservatives) on rat sensory neurons. We exposed primary dissociated rat dorsal root ganglia (DRG) sensory neurons to commercially available MPA for 24 hours with either the standard (commercial) concentration of preservatives or to different fractions following separation (MPA suspension whose preservative concentration had been reduced, or fractions containing higher concentrations of preservatives). Cells were stained with the TUNEL assay kit to detect apoptotic cells and images were taken on the Bio-Rad Laser Sharp-2000 system. We also detected expression of caspase-3, as an indicator of apoptosis in cell lysates. We exposed sensory neurons from rat DRG to different concentrations of MPA from the original commercially prepared vial. TUNEL assay showed dose-related responses and increased percentages of apoptotic cells with increasing concentrations of MPA. Increased concentrations of MPA caused 1.5 - 2 times higher caspase-3 expression in DRG sensory neurons than in control cells (ANOVA, P = 0.001). Our results showed that MPA with reduced preservatives caused significantly less apoptosis observed with TUNEL assay labeling (P neurons exposed to MPA from a commercially prepared vial or "clear phase" that contained higher concentrations of preservatives. Even though MPA with reduced preservatives caused 12.5% more apoptosis in DRG sensory

  11. Asymmetric development of dorsal and ventral attention networks in the human brain.

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    Farrant, Kristafor; Uddin, Lucina Q

    2015-04-01

    Two neural systems for goal-directed and stimulus-driven attention have been described in the adult human brain; the dorsal attention network (DAN) centered in the frontal eye fields (FEF) and intraparietal sulcus (IPS), and the ventral attention network (VAN) anchored in the temporoparietal junction (TPJ) and ventral frontal cortex (VFC). Little is known regarding the processes governing typical development of these attention networks in the brain. Here we use resting state functional MRI data collected from thirty 7 to 12 year-old children and thirty 18 to 31 year-old adults to examine two key regions of interest from the dorsal and ventral attention networks. We found that for the DAN nodes (IPS and FEF), children showed greater functional connectivity with regions within the network compared with adults, whereas adults showed greater functional connectivity between the FEF and extra-network regions including the posterior cingulate cortex. For the VAN nodes (TPJ and VFC), adults showed greater functional connectivity with regions within the network compared with children. Children showed greater functional connectivity between VFC and nodes of the salience network. This asymmetric pattern of development of attention networks may be a neural signature of the shift from over-representation of bottom-up attention mechanisms to greater top-down attentional capacities with development. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Asymmetric development of dorsal and ventral attention networks in the human brain

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    Kristafor Farrant

    2015-04-01

    Full Text Available Two neural systems for goal-directed and stimulus-driven attention have been described in the adult human brain; the dorsal attention network (DAN centered in the frontal eye fields (FEF and intraparietal sulcus (IPS, and the ventral attention network (VAN anchored in the temporoparietal junction (TPJ and ventral frontal cortex (VFC. Little is known regarding the processes governing typical development of these attention networks in the brain. Here we use resting state functional MRI data collected from thirty 7 to 12 year-old children and thirty 18 to 31 year-old adults to examine two key regions of interest from the dorsal and ventral attention networks. We found that for the DAN nodes (IPS and FEF, children showed greater functional connectivity with regions within the network compared with adults, whereas adults showed greater functional connectivity between the FEF and extra-network regions including the posterior cingulate cortex. For the VAN nodes (TPJ and VFC, adults showed greater functional connectivity with regions within the network compared with children. Children showed greater functional connectivity between VFC and nodes of the salience network. This asymmetric pattern of development of attention networks may be a neural signature of the shift from over-representation of bottom-up attention mechanisms to greater top-down attentional capacities with development.

  13. Dorsal Root Ganglion Stimulation for Complex Regional Pain Syndrome (CRPS) Recurrence after Amputation for CRPS, and Failure of Conventional Spinal Cord Stimulation.

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    Goebel, Andreas; Lewis, Sarah; Phillip, Rhodri; Sharma, Manohar

    2017-04-18

    Limb amputation is sometimes being performed in long-standing complex regional pain syndrome (CRPS), although little evidence is available guiding management decisions, including how CRPS recurrence should be managed. This report details the management of a young soldier with CRPS recurrence 2 years after midtibial amputation for CRPS. Conventional spinal cord stimulation did not achieve paraesthetic coverage, or pain relief in the stump, whereas L4 dorsal root ganglion stimulation achieved both coverage and initially modest pain relief, and over time, substantial pain relief. Current evidence does not support the use of amputation to improve either pain or function in CRPS. Before a decision is made, in exceptional cases, about referral for amputation, dorsal root ganglion stimulation should be considered as a potentially effective treatment, even where conventional spinal cord stimulator treatment has failed to achieve reliable paraesthetic cover. Furthermore, this treatment may provide pain relief in those patients with CRPS recurrence in the stump after amputation. © 2017 World Institute of Pain.

  14. Inhibition of [3H]resiniferatoxin binding to rat dorsal root ganglion membranes as a novel approach in evaluating compounds with capsaicin-like activity.

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    Szallasi, A; Szolcsanyi, J; Szallasi, Z; Blumberg, P M

    1991-11-01

    We have recently reported the specific binding of [3H]resiniferatoxin to sensory ganglion membranes; this binding appears to represent the postulated vanilloid (capsaicin) receptor. In the present report, we compare the structure/activity relations for binding to rat dorsal root ganglion membranes and for biological responses in the rat, using a series of vanilloids of the capsaicin (homovanilloyl-decylamide, homovanilloyl-dodecylamide, homovanilloyl-cyclododecylamide, homovanilloyl-hexadecylamide, homovanilloyl-piperidine and nonenoyl-homoveratrylamide) and resiniferatoxin (tinyatoxin, 12-deoxyphorbol 13-phenylacetate 20-homovanillate) classes. We find that all the tested biologically active vanilloids, but not the inactive structure analogs, compete for the [3H]resiniferatoxin binding sites in rat dorsal root ganglion membranes, and we conclude that the [3H]resiniferatoxin binding assay may provide an efficient approach for evaluating such compounds. We also provide evidence that the [3H]resiniferatoxin receptor is likely to recognize vanilloids which are inserted into the membranes; and that the apparent activity of capsaicinoids may be significantly influenced by factors other than equilibrium binding affinities.

  15. Neurite growth acceleration of adult Dorsal Root Ganglion neurons illuminated by low-level Light Emitting Diode light at 645 nm.

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    Burland, Marion; Paris, Lambert; Quintana, Patrice; Bec, Jean-Michel; Diouloufet, Lucie; Sar, Chamroeun; Boukhaddaoui, Hassan; Charlot, Benoit; Braga Silva, Jefferson; Chammas, Michel; Sieso, Victor; Valmier, Jean; Bardin, Fabrice

    2015-06-01

    The effect of a 645 nm Light Emitting Diode (LED) light irradiation on the neurite growth velocity of adult Dorsal Root Ganglion (DRG) neurons with peripheral axon injury 4-10 days before plating and without previous injury was investigated. The real amount of light reaching the neurons was calculated by taking into account the optical characteristics of the light source and of media in the light path. The knowledge of these parameters is essential to be able to compare results of the literature and a way to reduce inconsistencies. We found that 4 min irradiation of a mean irradiance of 11.3 mW/cm(2) (corresponding to an actual irradiance reaching the neurons of 83 mW/cm(2)) induced a 1.6-fold neurite growth acceleration on non-injured neurons and on axotomized neurons. Although the axotomized neurons were naturally already in a rapid regeneration process, an enhancement was found to occur while irradiating with the LED light, which may be promising for therapy applications. Dorsal Root Ganglion neurons (A) without previous injury and (B) subjected to a conditioning injury. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Effect of TRPV4-p38 MAPK Pathway on Neuropathic Pain in Rats with Chronic Compression of the Dorsal Root Ganglion

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    Yu-Juan Qu

    2016-01-01

    Full Text Available The aim of this study was to investigate the relationships among TRPV4, p38, and neuropathic pain in a rat model of chronic compression of the dorsal root ganglion. Mechanical allodynia appeared after CCD surgery, enhanced via the intrathecal injection of 4α-phorbol 12,13-didecanoate (4α-PDD, an agonist of TRPV4 and anisomycin (an agonist of p38, but was suppressed by Ruthenium Red (RR, an inhibitor of TRPV4 and SB203580 (an inhibitor of p38. The protein expressions of p38 and P-p38 were upregulated by 4α-PDD and anisomycin injection but reduced by RR and SB203580. Moreover, TRPV4 was upregulated by 4α-PDD and SB203580 and downregulated by RR and anisomycin. In DRG tissues, the numbers of TRPV4- or p38-positive small neurons were significantly changed in CCD rats, increased by the agonists, and decreased by the inhibitors. The amplitudes of ectopic discharges were increased by 4α-PDD and anisomycin but decreased by RR and SB203580. Collectively, these results support the link between TRPV4 and p38 and their intermediary role for neuropathic pain in rats with chronic compression of the dorsal root ganglion.

  17. Effects of niflumic acid on γ-aminobutyric acid-induced currents in isolated dorsal root ganglion neurons of neuropathic pain rats.

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    Wang, Li-Jie; Wang, Yang; Chen, Meng-Jie; Tian, Zhen-Pu; Lu, Bi-Han; Mao, Ke-Tao; Zhang, Liang; Zhao, Lei; Shan, Li-Ya; Li, Li; Si, Jun-Qiang

    2017-08-01

    Niflumic acid (NFA) is a type of non-steroidal anti-inflammatory drug. Neuropathic pain is caused by a decrease in presynaptic inhibition mediated by γ-aminobutyric acid (GABA). In the present study, a whole-cell patch-clamp technique and intracellular recording were used to assess the effect of NFA on GABA-induced inward current in dorsal root ganglion (DRG) neurons of a chronic constriction injury (CCI) model. It was observed that 1-1,000 µmol/l GABA induced a concentration-dependent inward current in DRG neurons. Compared with pseudo-operated rats, the thermal withdrawal latency (TWL) of CCI rats significantly decreased (PNFA group (50 and 300 µmol/l) were significantly longer than that of the CCI group (PNFA (5.32±3.51, 33.8±5.20, and 52.2±6.32%, respectively; PNFA, respectively (PNFA exerted a strong inhibitory effect on the peak value of GABA-induced current, and the GABA-induced response was inhibited by the same concentrations of NFA (1, 10 and 100 µmol/l) in the control and CCI groups (PNFA reduced the primary afferent depolarization (PAD) associated with neuropathic pain and mediated by the GABAA receptor. NFA may regulate neuropathic pain by inhibiting dorsal root reflexes, which are triggered PAD.

  18. TNF-α enhances the currents of voltage gated sodium channels in uninjured dorsal root ganglion neurons following motor nerve injury.

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    Chen, Xi; Pang, Rui-Ping; Shen, Kai-Feng; Zimmermann, Manfred; Xin, Wen-Jun; Li, Yong-Yong; Liu, Xian-Guo

    2011-02-01

    The ectopic discharges observed in uninjured dorsal root ganglion (DRG) neurons following various lesions of spinal nerves have been attributed to functional alterations of voltage-gated sodium channels (VGSCs). Such mechanisms may be important for the development of neuropathic pain. However, the pathophysiology underlying the functional modulation of VGSCs following nerve injury is largely unknown. Here, we studied this issue with use of a selective lumbar 5 ventral root transection (L5-VRT) model, in which dorsal root ganglion (DRG) neurons remain intact. We found that the L5-VRT increased the current densities of TTX-sensitive Na channels as well as currents in Nav1.8, but not Nav1.9 channels in uninjured DRG neurons. The thresholds of action potentials decreased and firing rates increased in DRG neurons following L5-VRT. As we found that levels of tumor necrosis factor-alpha (TNF-α) increased in cerebrospinal fluid (CSF) and in DRG tissue after L5-VRT, we tested whether the increased TNF-α might result in the changes in sodium channels. Indeed, recombinant rat TNF (rrTNF) enhanced the current densities of TTX-S and Nav1.8 in cultured DRG neurons dose-dependently. Furthermore, genetic deletion of TNF receptor 1 (TNFR-1) in mice attenuated the mechanical allodynia and prevented the increase in sodium currents in DRG neurons induced by L5-VRT. These data suggest that the increase in sodium currents in uninjured DRG neurons following nerve injury might be mediated by over-production of TNF-α. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Effects of dorsal root ganglion destruction by adriamycin in patients with postherpetic neuralgia Efeitos da destruição da raiz dorsal ganglionar pela adriamicina em pacientes com neuralgia pós-herpética

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    He Chun-jing

    2012-06-01

    Full Text Available PURPOSE: To investigate the effects of dorsal root ganglion destruction in patients with postherpetic neuralgia (PHN. METHODS: Seventy-two patients with PHN selected were randomly divided into two groups (n=36. Group A was the control group (treated by injection and group B was the group of dorsal root ganglion destruction by adriamycin. Visual analog scale scores (VAS, SAS, SF-MPQ scores. Clinical effects and therapy safety were evaluated before therapy, one week, three and six months after therapy. Forty-four patients were available for intention-to-treat analysis. RESULTS: The average pain scores on the Likert scale were significantly reduced at each point in group B. Patients in group B reported clinical effectiveness at six months as excellent response, good response, improved but unsatisfactory or unchanged 16, 12 and 8.VAS scores at each time point after the operation were lower than that before operation and in group A, there was significant difference. Patients showed significant improvement in sleep scores in group B. There was significant difference at T2 in group A than T1. There was no significant difference in group A at T3, T4 after the operation than that before operation. Between group comparison: there was significant difference between group A and group B at each time point after the operation. CONCLUSIONS: Dorsal root ganglion destruction by adriamycin under guidance of C-arm perspective, the puncture operation was accurate without any adverse reaction or serious complications, which could effectively relieve pain of patients with postherpetic neuralgia, but the long-term effects needed further study.OBJETIVO: Investigar os efeitos da destruição da raiz dorsal ganglionar em pacientes com neuralgia pós-herpética. MÉTODOS: Setenta e dois pacientes selecionados com neuralgia pós-herpética foram randomicamente distribuídos em dois grupos (n=36. Grupo A foi o grupo controle (tratado por injeção e o grupo B foi o grupo

  20. The Locus Coeruleus–Norepinephrine System Mediates Empathy for Pain through Selective Up-Regulation of P2X3 Receptor in Dorsal Root Ganglia in Rats

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    Yun-Fei Lü

    2017-09-01

    Full Text Available Empathy for pain (vicariously felt pain, an ability to feel, recognize, understand and share the painful emotions of others, has been gradually accepted to be a common identity in both humans and rodents, however, the underlying neural and molecular mechanisms are largely unknown. Recently, we have developed a rat model of empathy for pain in which pain can be transferred from a cagemate demonstrator (CD in pain to a naïve cagemate observer (CO after 30 min dyadic priming social interaction. The naïve CO rats display both mechanical pain hypersensitivity (hyperalgesia and enhanced spinal nociception. Chemical lesions of bilateral medial prefrontal cortex (mPFC abolish the empathic pain response completely, suggesting existence of a top-down facilitation system in production of empathy for pain. However, the social transfer of pain was not observed in non-cagemate observer (NCO after dyadic social interaction with a non-cagemate demonstrator (NCD in pain. Here we showed that dyadic social interaction with a painful CD resulted in elevation of circulating norepinephrine (NE and increased neuronal activity in the locus coeruleus (LC in the CO rats. Meanwhile, CO rats also had over-expression of P2X3, but not TRPV1, in the dorsal root ganglia (DRG. Chemical lesion of the LC-NE neurons by systemic DSP-4 and pharmacological inhibition of central synaptic release of NE by clonidine completely abolished increase in circulating NE and P2X3 receptor expression, as well as the sympathetically-maintained development of empathic mechanical hyperalgesia. However, in the NCO rats, neither the LC-NE neuronal activity nor the P2X3 receptor expression was altered after dyadic social interaction with a painful NCD although the circulating corticosterone and NE were elevated. Finally, in the periphery, both P2X3 receptor and α1 adrenergic receptor were found to be involved in the development of empathic mechanical hyperalgesia. Taken together with our previous

  1. Dissociation of retinal and headcentric disparity signals in dorsal human cortex

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    Arnoldussen, David M.; Goossens, Jeroen; van Den Berg, Albert V.

    2015-01-01

    Recent fMRI studies have shown fusion of visual motion and disparity signals for shape perception (Ban et al., 2012), and unmasking camouflaged surfaces (Rokers et al., 2009), but no such interaction is known for typical dorsal motion pathway tasks, like grasping and navigation. Here, we investigate human speed perception of forward motion and its representation in the human motion network. We observe strong interaction in medial (V3ab, V6) and lateral motion areas (MT+), which differ significantly. Whereas the retinal disparity dominates the binocular contribution to the BOLD activity in the anterior part of area MT+, headcentric disparity modulation of the BOLD response dominates in area V3ab and V6. This suggests that medial motion areas not only represent rotational speed of the head (Arnoldussen et al., 2011), but also translational speed of the head relative to the scene. Interestingly, a strong response to vergence eye movements was found in area V1, which showed a dependency on visual direction, just like vertical-size disparity. This is the first report of a vertical-size disparity correlate in human striate cortex. PMID:25759642

  2. Dissociation of retinal and headcentric disparity signals in dorsal human cortex

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    David Mattijs Arnoldussen

    2015-02-01

    Full Text Available Recent fMRI studies have shown fusion of visual motion and disparity signals for shape perception (Ban et al., 2012, and unmasking camouflaged surfaces (Rokers et al., 2009, but no such interaction is known for typical dorsal motion pathway tasks, like grasping and navigation. Here, we investigate human speed perception of forward motion and its representation in the human motion network. We observe strong interaction in medial (V3ab, V6 and lateral motion areas (MT+, which differ significantly. Whereas the retinal disparity dominates the binocular contribution to the BOLD activity in the anterior part of area MT+, headcentric disparity modulation of the BOLD response dominates in area V3ab and V6. This suggests that medial motion areas not only represent rotational speed of the head (Arnoldussen et al., 2011, but also translational speed of the head relative to the scene.Interestingly, a strong response to vergence eye movements was found in area V1, which showed a dependency on visual direction, just like vertical-size disparity. This is the first report of a vertical-size disparity correlate in human striate cortex.

  3. Peripheral effects of morphine and expression of μ-opioid receptors in the dorsal root ganglia during neuropathic pain: nitric oxide signaling

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    Pol Olga

    2011-04-01

    Full Text Available Abstract Background The local administration of μ-opioid receptor (MOR agonists attenuates neuropathic pain but the precise mechanism implicated in this effect is not completely elucidated. We investigated if nitric oxide synthesized by neuronal (NOS1 or inducible (NOS2 nitric oxide synthases could modulate the local antiallodynic effects of morphine through the peripheral nitric oxide-cGMP-protein kinase G (PKG-ATP-sensitive K+ (KATP channels signaling pathway activation and affect the dorsal root ganglia MOR expression during neuropathic pain. Results In wild type (WT mice, the subplantar administration of morphine dose-dependently decreased the mechanical and thermal allodynia induced by the chronic constriction of the sciatic nerve (CCI, which effects were significantly diminished after their co-administration with different subanalgesic doses of a selective NOS1 (N-[(4S-4-amino-5-[(2-aminoethylamino]pentyl]-N'-nitroguanidine tris(trifluoroacetate salt; NANT, NOS2 (L-N(6-(1-iminoethyl-lysine; L-NIL, L-guanylate cyclase (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one; ODQ, PKG ((Rp-8-(para-chlorophenylthioguanosine-3',5'-cyclic monophosphorothioate; Rp-8-pCPT-cGMPs inhibitor or a KATP channel blocker (glibenclamide. The evaluation of the expression of MOR in the dorsal root ganglia from sham-operated and sciatic nerve-injured WT, NOS1 knockout (KO and NOS2-KO mice at 21 days after surgery demonstrated that, although the basal mRNA and protein levels of MOR were similar between WT and both NOS-KO animals, nerve injury only decreased their expression in WT mice. Conclusions These results suggest that the peripheral nitric oxide-cGMP-PKG-KATP signaling pathway activation participates in the local antiallodynic effects of morphine after sciatic nerve injury and that nitric oxide, synthesized by NOS1 and NOS2, is implicated in the dorsal root ganglia down-regulation of MOR during neuropathic pain.

  4. Enhanced excitability of primary sensory neurons and altered gene expression of neuronal ion channels in dorsal root ganglion in paclitaxel-induced peripheral neuropathy.

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    Zhang, Haijun; Dougherty, Patrick M

    2014-06-01

    The mechanism of chemotherapy-induced peripheral neuropathy after paclitaxel treatment is not well understood. Given the poor penetration of paclitaxel into central nervous system, peripheral nervous system is most at risk. Intrinsic membrane properties of dorsal root ganglion neurons were studied by intracellular recordings. Multiple-gene real-time polymerase chain reaction array was used to investigate gene expression of dorsal root ganglion neuronal ion channels. Paclitaxel increased the incidence of spontaneous activity from 4.8 to 27.1% in large-sized and from 0 to 33.3% in medium-sized neurons. Paclitaxel decreased the rheobase (nA) from 1.6 ± 0.1 to 0.8 ± 0.1 in large-sized, from 1.5 ± 0.2 to 0.6 ± 0.1 in medium-sized, and from 1.6 ± 0.2 to 1.0 ± 0.1 in small-sized neurons. After paclitaxel treatment, other characteristics of membrane properties in each group remained the same except that Aδ neurons showed shorter action potential fall time (ms) (1.0 ± 0.2, n = 10 vs. 1.8 ± 0.3, n = 9, paclitaxel vs. vehicle). Meanwhile, real-time polymerase chain reaction array revealed an alteration in expression of some neuronal ion channel genes including up-regulation of hyperpolarization-activated cyclic nucleotide-gated channel 1 (fold change 1.76 ± 0.06) and Nav1.7 (1.26 ± 0.02) and down-regulation of Kir channels (Kir1.1, 0.73 ± 0.05, Kir3.4, 0.66 ± 0.06) in paclitaxel-treated animals. The increased neuronal excitability and the changes in gene expression of some neuronal ion channels in dorsal root ganglion may provide insight into the molecular and cellular basis of paclitaxel-induced neuropathy, which may lead to novel therapeutic strategies.

  5. Statistical analysis of the spontaneously emitted photon signals from palm and dorsal sides of both hands in human subjects

    NARCIS (Netherlands)

    Wijk, E.P.A. van; Wijk, R.V.; Bajpai, R.P.; Greef, J. van der

    2010-01-01

    Photon signals emitted spontaneously from dorsal and palm sides of both hands were recorded using 6000 time windows of size T=50. ms in 50 healthy human subjects. These photon signals demonstrated universal behaviour by variance and mean. The data sets for larger time windows up to T=50. s were

  6. G protein-gated inwardly rectifying potassium channel subunits 1 and 2 are down-regulated in rat dorsal root ganglion neurons and spinal cord after peripheral axotomy.

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    Lyu, Chuang; Mulder, Jan; Barde, Swapnali; Sahlholm, Kristoffer; Zeberg, Hugo; Nilsson, Johanna; Århem, Peter; Hökfelt, Tomas; Fried, Kaj; Shi, Tie-Jun Sten

    2015-07-22

    Increased nociceptive neuronal excitability underlies chronic pain conditions. Various ion channels, including sodium, calcium and potassium channels have pivotal roles in the control of neuronal excitability. The members of the family of G protein-gated inwardly rectifying potassium (GIRK) channels, GIRK1-4, have been implicated in modulating excitability. Here, we investigated the expression and distribution of GIRK1 and GIRK2 in normal and injured dorsal root ganglia (DRGs) and spinal cord of rats. We found that ~70% of the DRG neurons expressed GIRK1, while only <10% expressed GIRK2. The neurochemical profiles of GIRK1- and GIRK2-immunoreactive neurons were characterized using the neuronal markers calcitonin gene-related peptide, isolectin-B4 and neurofilament-200, and the calcium-binding proteins calbindin D28k, calretinin, parvalbumin and secretagogin. Both GIRK subunits were expressed in DRG neurons with nociceptive characteristics. However, while GIRK1 was widely expressed in several sensory neuronal subtypes, GIRK2 was detected mainly in a group of small C-fiber neurons. In the spinal dorsal horn, GIRK1- and -2-positive cell bodies and processes were mainly observed in lamina II, but also in superficial and deeper layers. Abundant GIRK1-, but not GIRK2-like immunoreactivity, was found in the ventral horn (laminae VI-X). Fourteen days after axotomy, GIRK1 and GIRK2 were down-regulated in DRG neurons at the mRNA and protein levels. Both after axotomy and rhizotomy there was a reduction of GIRK1- and -2-positive processes in the dorsal horn, suggesting a presynaptic localization of these potassium channels. Furthermore, nerve ligation caused accumulation of both subunits on both sides of the lesion, providing evidence for anterograde and retrograde fast axonal transport. Our data support the hypothesis that reduced GIRK function is associated with increased neuronal excitability and causes sensory disturbances in post-injury conditions, including neuropathic

  7. Spinorphin inhibits membrane depolarization- and capsaicin-induced intracellular calcium signals in rat primary nociceptive dorsal root ganglion neurons in culture.

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    Ayar, Ahmet; Ozcan, Mete; Kuzgun, Kemal Tuğrul; Kalkan, Omer Faruk

    2015-01-01

    Spinorphin is a potential endogenous antinociceptive agent although the mechanism(s) of its analgesic effect remain unknown. We conducted this study to investigate, by considering intracellular calcium concentrations as a key signal for nociceptive transmission, the effects of spinorphin on cytoplasmic Ca(2+) ([Ca(2+)]i) transients, evoked by high-K(+) (30 mM) depolariasation or capsaicin, and to determine whether there were any differences in the effects of spinorphin among subpopulation of cultured rat dorsal root ganglion (DRG) neurons. DRG neurons were cultured on glass coverslips following enzymatic digestion and mechanical agitation, and loaded with the calcium sensitive dye fura-2 AM (1 µM). Intracellular calcium responses in individual DRG neurons were quantified using standard fura-2 based ratiometric calcium imaging technique. All data were analyzed by using unpaired t test, p nociceptive subtypes of this primary sensory neurons suggesting that peripheral site is involved in the pain modulating effect of this endogenous agent.

  8. Effects of dragon's blood resin and its component loureirin B on tetrodotoxin-sensitive voltage-gated sodium currents in rat dorsal root ganglion neurons.

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    Xiangming, Liu; Su, Chen; Shijin, Yin; Zhinan, Mei

    2004-08-01

    Using whole-cell patch clamp technique on the membrane of freshly isolated dorsal root ganglion (DRG) neurons, the effects of dragon's blood resin and its important component loureirin B on tetrodotoxin-sensitive (TTX-S) voltage-gated sodium currents were observed. The results show that both blood resin and loureirin B could suppress TTX-S voltage-gated sodium currents in a dose-dependent way. The peak current amplitudes and the steady-state activation and inactivation curves are also made to shift by 0.05% blood resin and 0.2 mmol/L loureirin B. These results demonstrate that the effects of blood resin on TTX-S sodium current may contribute to loureirin B in blood resin. Perhaps the analgesic effect of blood resin is caused partly by loureirin B directly interfering with the nociceptive transmission of primary sensory neurons.

  9. Muscle injury in rats induces upregulation of inflammatory cytokines in injured muscle and calcitonin gene-related peptide in dorsal root ganglia innervating the injured muscle.

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    Sakuma, Yoshihiro; Miyagi, Masayuki; Inoue, Gen; Ishikawa, Tetsuhiro; Kamoda, Hiroto; Yamauchi, Kazuyo; Orita, Sumihisa; Suzuki, Miyako; Oikawa, Yasuhiro; Inage, Kazuhide; Kubota, Go; Sainoh, Takeshi; Sato, Jun; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-10-01

    In this study we evaluated the relationships among the behavioral changes after muscle injury, histological changes, changes in inflammatory cytokines in the injured muscle, and changes in the sensory nervous system innervating the muscle in rats. We established a model of muscle injury in rats using a dropped weight. Behavior was assessed using the CatWalk system. Subsequently, bilateral gastrocnemius muscles and dorsal root ganglia (DRGs) were resected. Muscles were stained with hematoxylin and eosin, and inflammatory cytokines in injured muscles were assayed. DRGs were immunostained for calcitonin gene-related peptide (CGRP). Changes of behavior and upregulation of inflammatory cytokines in injured muscles subsided within 2 days of injury. Repaired tissue was observed 3 weeks after injury. However, upregulation of CGRP in DRG neurons continued for 2 weeks after injury. These findings may explain in part the pathological mechanism of persistent muscle pain. Muscle Nerve 54: 776-782, 2016. © 2016 The Authors Muscle & Nerve Published by Wiley Periodicals, Inc.

  10. SPATIAL DIFFERENCES IN FATIGUE-ASSOCIATED ELECTROMYOGRAPHIC BEHAVIOR OF THE HUMAN FIRST DORSAL INTEROSSEUS MUSCLE

    NARCIS (Netherlands)

    ZIJDEWIND, Inge; KERNELL, D; KUKULKA, CG

    1995-01-01

    1. Fatigue-associated electromyographic (EMG) reactions of intrinsic hand muscles were studied during maintained isometric voluntary contractions of normal subjects. Most measurements concerned actions of the first dorsal interosseus (FDI). In a smaller number of subjects, complementary measurements

  11. Autologous nucleus pulposus transplantation to lumbar 5 dorsal root ganglion after epineurium dissection in rats: a modified model of non-compressive lumbar herniated intervertebral disc.

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    Zhang, Jin-jun; Song, Wu; Luo, Wen-ying; Wei, Ming; Sun, Lai-bao; Zou, Xue-nong; Liao, Wei-ming

    2011-07-05

    Nucleus pulposus of intervertebral discs has proinflammatory characteristics that play a key role in neuropathic pain in lumbar herniated intervertebral disc. One of the most commonly used animal models (the traditional model) of non-compressive lumbar herniated intervertebral disc is created by L4-L5 hemilaminectomy and the application of autologous nucleus pulposus to cover the left L4 and L5 nerve roots in rats. However, such procedures have the disadvantages of excessive trauma and low success rate. We proposed a modified model of non-compressive lumbar herniated intervertebral disc in which only the left L5 dorsal root ganglion is exposed and transplanted with autologous nucleus pulposus following incision of epineurium. We aimed to compare the modified model with the traditional one with regard to trauma and success rate. Thirty Sprague-Dawley male rats were randomized into three groups: sham operation group (n = 6), traditional group (n = 12), and modified group (n = 12). The amount of blood loss and operative time for each group were analyzed. The paw withdrawal threshold of the left hind limb to mechanical stimuli and paw withdrawal latency to heat stimuli were examined from the day before surgery to day 35 after surgery. Compared with the traditional group, the modified group had shorter operative time, smaller amount of blood loss, and higher success rate (91.7% versus 58.3%, P lumbar herniated intervertebral disc with less trauma and more stable pain ethology.

  12. Efficacy and factors determining the outcome of dorsal root entry zone lesioning procedure (DREZotomy) in the treatment of intractable pain syndrome.

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    Piyawattanametha, Nontaphon; Sitthinamsuwan, Bunpot; Euasobhon, Pramote; Zinboonyahgoon, Nantthasorn; Rushatamukayanunt, Pranee; Nunta-Aree, Sarun

    2017-10-09

    Chronic pain is a disabling condition that adversely affects patient quality of life. The dorsal root entry zone lesioning procedure (DREZotomy) is a modality used to treat intractable pain caused by insults to neural structures. This study aimed to investigate the efficacy of and the factors that determine the outcome of microsurgical DREZotomy (MDT). All consecutive patients who underwent MDT for treatment of intractable pain during September 2008 to December 2016 were enrolled. Demographic data, clinical characteristics, intraoperative findings, and postoperative outcomes were analyzed. The 40 included patients underwent MDT for relief of intractable pain caused by 27 brachial plexus injuries (BPIs), 6 spinal cord injuries, 3 neoplasms, and 4 other causes. A significant reduction in pain was observed post-MDT for both average (p dermatomes (OR, 1.30; 95% CI, 1.01-1.67; p = 0.039) were significantly associated with good maximal pain relief. MDT is an effective procedure for treatment of intractable pain in well-selected patients, particularly in cases with brachial plexus avulsion pain. Injury of the spinal nerve root (brachial plexus avulsion and cauda equina injury) was associated with good average pain relief and pain freedom, and electrical pain and lower number of painful dermatomes were associated with good maximal pain relief. The results are useful in the selection of candidates for DREZotomy and prediction of surgical outcome.

  13. Upregulation of adrenomedullin in the spinal cord and dorsal root ganglia in the early phase of CFA-induced inflammation in rats.

    Science.gov (United States)

    Hong, Yanguo; Liu, Yushan; Chabot, Jean-Guy; Fournier, Alain; Quirion, Rémi

    2009-11-01

    Adrenomedullin (AM), a member of calcitonin gene-related peptide (CGRP) family, has been demonstrated to be a pronociceptive mediator [28]. This study was undertaken to investigate the role of AM in a model of complete Freund's adjuvant (CFA)-induced inflammatory pain. Injection of CFA, but not of saline, in the unilateral hindpaw produced an increase in the expression of AM-like immunoreactivity (AM-IR) in laminae I-II of the spinal cord as well as in small- and medium-sized dorsal root ganglion (DRG) neurons at 48 h. The content of AM in DRG on the side ipsilateral to CFA injection started to increase at 4 h and remained at high levels at 24 and 48 h. The selective antagonist of AM receptors, AM(22-52), administered intrathecally (i.t.) 24 h after CFA injection inhibited inflammation-associated hyperalgesia in a dose-dependent manner (2, 5 and 10 nmol). Impressively, this anti-hyperalgesic effect lasted for at least 24 h. I.t. administration of AM(22-52) (10 nmol) also reversed CFA-induced increase in AM-IR in the spinal dorsal horn and DRG. Furthermore, blockade of AM receptors abolished CFA-induced changes in the expression and content of CGRP-like immunoreactivity in these regions. Taken together, our results suggest that the upregulation of AM in DRG neurons contributes to the development of inflammatory pain, and this effect is mediated, at least in part, by enhancing the expression and release of CGRP. Blocking AM receptor downstream signaling effects using antagonists has the potential of relieving pain following the induction of inflammation.

  14. Accuracy assessment of a surface electromyogram decomposition system in human first dorsal interosseus muscle

    Science.gov (United States)

    Hu, Xiaogang; Rymer, William Z.; Suresh, Nina L.

    2014-04-01

    Objective. The aim of this study is to assess the accuracy of a surface electromyogram (sEMG) motor unit (MU) decomposition algorithm during low levels of muscle contraction. Approach. A two-source method was used to verify the accuracy of the sEMG decomposition system, by utilizing simultaneous intramuscular and surface EMG recordings from the human first dorsal interosseous muscle recorded during isometric trapezoidal force contractions. Spike trains from each recording type were decomposed independently utilizing two different algorithms, EMGlab and dEMG decomposition algorithms. The degree of agreement of the decomposed spike timings was assessed for three different segments of the EMG signals, corresponding to specified regions in the force task. A regression analysis was performed to examine whether certain properties of the sEMG and force signal can predict the decomposition accuracy. Main results. The average accuracy of successful decomposition among the 119 MUs that were common to both intramuscular and surface records was approximately 95%, and the accuracy was comparable between the different segments of the sEMG signals (i.e., force ramp-up versus steady state force versus combined). The regression function between the accuracy and properties of sEMG and force signals revealed that the signal-to-noise ratio of the action potential and stability in the action potential records were significant predictors of the surface decomposition accuracy. Significance. The outcomes of our study confirm the accuracy of the sEMG decomposition algorithm during low muscle contraction levels and provide confidence in the overall validity of the surface dEMG decomposition algorithm.

  15. Bromodomain-containing Protein 4 Activates Voltage-gated Sodium Channel 1.7 Transcription in Dorsal Root Ganglia Neurons to Mediate Thermal Hyperalgesia in Rats.

    Science.gov (United States)

    Hsieh, Ming-Chun; Ho, Yu-Cheng; Lai, Cheng-Yuan; Wang, Hsueh-Hsiao; Lee, An-Sheng; Cheng, Jen-Kun; Chau, Yat-Pang; Peng, Hsien-Yu

    2017-11-01

    Bromodomain-containing protein 4 binds acetylated promoter histones and promotes transcription; however, the role of bromodomain-containing protein 4 in inflammatory hyperalgesia remains unclear. Male Sprague-Dawley rats received hind paw injections of complete Freund's adjuvant to induce hyperalgesia. The dorsal root ganglia were examined to detect changes in bromodomain-containing protein 4 expression and the activation of genes involved in the expression of voltage-gated sodium channel 1.7, which is a key pain-related ion channel. The intraplantar complete Freund's adjuvant injections resulted in thermal hyperalgesia (4.0 ± 1.5 s; n = 7). The immunohistochemistry and immunoblotting results demonstrated an increase in the bromodomain-containing protein 4-expressing dorsal root ganglia neurons (3.78 ± 0.38 fold; n = 7) and bromodomain-containing protein 4 protein levels (2.62 ± 0.39 fold; n = 6). After the complete Freund's adjuvant injection, histone H3 protein acetylation was enhanced in the voltage-gated sodium channel 1.7 promoter, and cyclin-dependent kinase 9 and phosphorylation of RNA polymerase II were recruited to this area. Furthermore, the voltage-gated sodium channel 1.7-mediated currents were enhanced in neurons of the complete Freund's adjuvant rats (55 ± 11 vs. 19 ± 9 pA/pF; n = 4 to 6 neurons). Using bromodomain-containing protein 4-targeted antisense small interfering RNA to the complete Freund's adjuvant-treated rats, the authors demonstrated a reduction in the expression of bromodomain-containing protein 4 (0.68 ± 0.16 fold; n = 7), a reduction in thermal hyperalgesia (7.5 ± 1.5 s; n = 7), and a reduction in the increased voltage-gated sodium channel 1.7 currents (21 ± 4 pA/pF; n = 4 to 6 neurons). Complete Freund's adjuvant triggers enhanced bromodomain-containing protein 4 expression, ultimately leading to the enhanced excitability of nociceptive neurons and thermal hyperalgesia. This effect is

  16. Dissociation of retinal and headcentric disparity signals in dorsal human cortex

    NARCIS (Netherlands)

    Arnoldussen, D.M.; Goossens, J.; Berg, A.V. van den

    2015-01-01

    Recent fMRI studies have shown fusion of visual motion and disparity signals for shape perception (Ban et al., 2012), and unmasking camouflaged surfaces (Rokers et al., 2009), but no such interaction is known for typical dorsal motion pathway tasks, like grasping and navigation. Here, we investigate

  17. Fatigue-associated changes in the electromyogram of the human first dorsal interosseous muscle

    NARCIS (Netherlands)

    Zijdewind, Inge; Zwarts, MJ; Kernell, D

    1999-01-01

    Muscle fatigue is a clinically important symptom, often analyzed using electromyography (EMG). We analyzed fatigue reactions of the first dorsal interosseous muscle (FDI) during a maintained contraction at half-maximal force (1/2-MVC test). EMGs were recorded with large surface electrodes and,

  18. Effects of serum immunoglobulins from patients with complex regional pain syndrome (CRPS) on depolarisation-induced calcium transients in isolated dorsal root ganglion (DRG) neurons.

    Science.gov (United States)

    Reilly, Joanne M; Dharmalingam, Backialakshmi; Marsh, Stephen J; Thompson, Victoria; Goebel, Andreas; Brown, David A

    2016-03-01

    Complex regional pain syndrome (CRPS) is thought to have an auto-immune component. One such target recently proposed from the effects of auto-immune IgGs on Ca(2+) transients in cardiac myocytes and cell lines is the α1-adrenoceptor. We have tested whether such IgGs exerted comparable effects on nociceptive sensory neurons isolated from rat dorsal root ganglia. Depolarisation-induced [Ca(2+)]i transients were generated by applying 30 mM KCl for 2 min and monitored by Fura-2 fluorescence imaging. No IgGs tested (including 3 from CRPS patients) had any significant effect on these [Ca(2+)]i transients. However, IgG from one CRPS patient consistently and significantly reduced the K(+)-induced response of cells that had been pre-incubated for 24h with a mixture of inflammatory mediators (1 μM histamine, 5-hydroxytryptamine, bradykinin and PGE2). Since this pre-incubation also appeared to induce a comparable inhibitory response to the α1-agonist phenylephrine, this is compatible with the α1-adrenoceptor as a target for CRPS auto-immunity. A mechanism whereby this might enhance pain is suggested. Copyright © 2015. Published by Elsevier Inc.

  19. Toll-like receptor 2 contributes to chemokine gene expression and macrophage infiltration in the dorsal root ganglia after peripheral nerve injury

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    Lee Sung Joong

    2011-09-01

    Full Text Available Abstract Background We have previously reported that nerve injury-induced neuropathic pain is attenuated in toll-like receptor 2 (TLR2 knock-out mice. In these mice, inflammatory gene expression and spinal cord microglia actvation is compromised, whereas the effects in the dorsal root ganglia (DRG have not been tested. In this study, we investigated the role of TLR2 in inflammatory responses in the DRG after peripheral nerve injury. Results L5 spinal nerve transection injury induced the expression of macrophage-attracting chemokines such as CCL2/MCP-1 and CCL3/MIP-1 and subsequent macrophage infiltration in the DRG of wild-type mice. In TLR2 knock-out mice, however, the induction of chemokine expression and macrophage infiltration following nerve injury were markedly reduced. Similarly, the induction of IL-1β and TNF-α expression in the DRG by spinal nerve injury was ameliorated in TLR2 knock-out mice. The reduced inflammatory response in the DRG was accompanied by attenuation of nerve injury-induced spontaneous pain hypersensitivity in TLR2 knock-out mice. Conclusions Our data show that TLR2 contributes to nerve injury-induced proinflammatory chemokine/cytokine gene expression and macrophage infiltration in the DRG, which may have relevance in the reduced pain hypersensitivity in TLR2 knock-out mice after spinal nerve injury.

  20. The Venom of the Spider Selenocosmia Jiafu Contains Various Neurotoxins Acting on Voltage-Gated Ion Channels in Rat Dorsal Root Ganglion Neurons

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    Zhaotun Hu

    2014-03-01

    Full Text Available Selenocosmia jiafu is a medium-sized theraphosid spider and an attractive source of venom, because it can be bred in captivity and it produces large amounts of venom. We performed reversed-phase high-performance liquid chromatography (RP-HPLC and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS analyses and showed that S. jiafu venom contains hundreds of peptides with a predominant mass of 3000–4500 Da. Patch clamp analyses indicated that the venom could inhibit voltage-gated Na+, K+ and Ca2+ channels in rat dorsal root ganglion (DRG neurons. The venom exhibited inhibitory effects on tetrodotoxin-resistant (TTX-R Na+ currents and T-type Ca2+ currents, suggesting the presence of antagonists to both channel types and providing a valuable tool for the investigation of these channels and for drug development. Intra-abdominal injection of the venom had severe toxic effects on cockroaches and caused death at higher concentrations. The LD50 was 84.24 μg/g of body weight in the cockroach. However, no visible symptoms or behavioral changes were detected after intraperitoneal injection of the venom into mice even at doses up to 10 mg/kg body weight. Our results provide a basis for further case-by-case investigations of peptide toxins from this venom.

  1. The role of TRPV1 in different subtypes of dorsal root ganglion neurons in rat chronic inflammatory nociception induced by complete Freund's adjuvant

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    Han Ji-Sheng

    2008-12-01

    Full Text Available Abstract Background The present study aims to investigate the role of transient receptor potential vanilloid 1 (TRPV1 in dorsal root ganglion (DRG neurons in chronic pain including thermal hyperalgesia and mechanical allodynia. Chronic inflammatory nociception of rats was produced by intraplantar injection of complete Freund's adjuvant (CFA and data was collected until day 28 following injection. Results Thermal hyperalgesia was evident from day 1 to day 28 with peak at day 7, while mechanical allodynia persisted from day 1 to day 14 and was greatest at day 7. Intrathecal administration of AMG 9810 at day 7, a selective TRPV1 antagonist, significantly reduced thermal hyperalgesia and mechanical allodynia. TRPV1 expression in DRG detected by Western blotting was increased relative to baseline throughout the observation period. Double labeling of TRPV1 with neuronal marker neurofilament 200 (NF200, calcitonin gene-related peptide (CGRP or isolectin B4 (IB4 was used to distinguish different subtypes of DRG neurons. TRPV1 expression was increased in the medium-sized myelinated A fiber (NF200 positive neurons and in small non-peptidergic (IB4 positive neurons from day 1 to day 14 and was increased in small peptidergic (CGRP positive neurons from day 1 to day 28. Conclusion TRPV1 expression increases in all three types of DRG neurons after CFA injection and plays a role in CFA-induced chronic inflammatory pain including thermal hyperalgesia and mechanical allodynia.

  2. Effects of (−-Gallocatechin-3-Gallate on Tetrodotoxin-Resistant Voltage-Gated Sodium Channels in Rat Dorsal Root Ganglion Neurons

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    Jian-Min Jiang

    2013-05-01

    Full Text Available The (−-gallocatechin-3-gallate (GCG concentration in some tea beverages can account for as much as 50% of the total catechins. It has been shown that catechins have analgesic properties. Voltage-gated sodium channels (Nav mediate neuronal action potentials. Tetrodotoxin inhibits all Nav isoforms, but Nav1.8 and Nav1.9 are relatively tetrodotoxin-resistant compared to other isoforms and functionally linked to nociception. In this study, the effects of GCG on tetrodotoxin-resistant Na+ currents were investigated in rat primary cultures of dorsal root ganglion neurons via the whole-cell patch-clamp technique. We found that 1 μM GCG reduced the amplitudes of peak current density of tetrodotoxin-resistant Na+ currents significantly. Furthermore, the inhibition was accompanied by a depolarizing shift of the activation voltage and a hyperpolarizing shift of steady-state inactivation voltage. The percentage block of GCG (1 μM on tetrodotoxin-resistant Na+ current was 45.1% ± 1.1% in 10 min. In addition, GCG did not produce frequency-dependent block of tetrodotoxin-resistant Na+ currents at stimulation frequencies of 1 Hz, 2 Hz and 5 Hz. On the basis of these findings, we propose that GCG may be a potential analgesic agent.

  3. Increase of sodium channels (nav 1.8 and nav 1.9) in rat dorsal root ganglion neurons exposed to autologous nucleus pulposus.

    Science.gov (United States)

    Watanabe, Kazuyuki; Larsson, Karin; Rydevik, Björn; Konno, Shin-Ichi; Nordborg, Claes; Olmarker, Kjell

    2014-01-01

    It has been assumed that nucleus pulposus-induced activation of the dorsal root ganglion (DRG) may be related to an activation of sodium channels in the DRG neurons. In this study we assessed the expression of Nav 1.8 and Nav 1.9 following disc puncture. Thirty female Sprague-Dawley rats were used. The L4/L5 disc was punctured by a needle (n=12) and compared to a sham group without disc puncture (n=12) and a naive group (n=6). At day 1 and 7, sections of the left L4 DRG were immunostained with anti-Nav 1.8 and Nav 1.9 antibodies. At day 1 after surgery, both Nav 1.8-IR neurons and Nav 1.9-IR neurons were significantly increased in the disc puncture group compared to the sham and naive groups (p<0.05), but not at day 7. The findings in the present study demonstrate a neuronal mechanism that may be of importance in the pathophysiology of sciatic pain in disc herniation.

  4. [A computer simulation research for the effects of dragon's blood and its component loureirin B on sodium channel in dorsal root ganglion cells].

    Science.gov (United States)

    Chen, Su; Liu, Xiangming

    2006-12-01

    Using patch clamp technique the effects of dragon's blood and its component loureirin B on tetrodotoxin-sensitive sodium channel currents in dorsal root ganglion cells were observed. The experimental data were simulated with Hodgkin-Huxley model and the corresponding parameters were estimated. In addition, computer-simulated neuron action potentials in the absence and presence of drugs were produced using Hodgkin-Huxley model. The results show that the conductance of tetrodotoxin-sensitive sodium channel was fitted with m3h model well, the half-activated potentials of the sodium channel in the presence of drugs were shifted to the depolarizing direction and the threshold intensity of the cells in the presence of drugs was increased. These results demonstrate that dragon's blood and loureirin B did not resemble the tetrodotoxin which inhibited tetrodotoxin-sensitive sodium channel currents completely. Perhaps the analgesic effects of dragon's blood were partly caused by loureirin B affecting the activation, blocking the action potential generation and interfering with the transmission of painful signals into the central nervous system.

  5. Neuro-fuzzy decoding of sensory information from ensembles of simultaneously recorded dorsal root ganglion neurons for functional electrical stimulation applications

    Science.gov (United States)

    Rigosa, J.; Weber, D. J.; Prochazka, A.; Stein, R. B.; Micera, S.

    2011-08-01

    Functional electrical stimulation (FES) is used to improve motor function after injury to the central nervous system. Some FES systems use artificial sensors to switch between finite control states. To optimize FES control of the complex behavior of the musculo-skeletal system in activities of daily life, it is highly desirable to implement feedback control. In theory, sensory neural signals could provide the required control signals. Recent studies have demonstrated the feasibility of deriving limb-state estimates from the firing rates of primary afferent neurons recorded in dorsal root ganglia (DRG). These studies used multiple linear regression (MLR) methods to generate estimates of limb position and velocity based on a weighted sum of firing rates in an ensemble of simultaneously recorded DRG neurons. The aim of this study was to test whether the use of a neuro-fuzzy (NF) algorithm (the generalized dynamic fuzzy neural networks (GD-FNN)) could improve the performance, robustness and ability to generalize from training to test sets compared to the MLR technique. NF and MLR decoding methods were applied to ensemble DRG recordings obtained during passive and active limb movements in anesthetized and freely moving cats. The GD-FNN model provided more accurate estimates of limb state and generalized better to novel movement patterns. Future efforts will focus on implementing these neural recording and decoding methods in real time to provide closed-loop control of FES using the information extracted from sensory neurons.

  6. Extracellular Nm23H1 stimulates neurite outgrowth from dorsal root ganglia neurons in vitro independently of nerve growth factor supplementation or its nucleoside diphosphate kinase activity.

    Science.gov (United States)

    Wright, K T; Seabright, R; Logan, A; Lilly, A J; Khanim, F; Bunce, C M; Johnson, W E B

    2010-07-16

    The nucleoside diphosphate (NDP) kinase, Nm23H1, is a highly expressed during neuronal development, whilst induced over-expression in neuronal cells results in increased neurite outgrowth. Extracellular Nm23H1 affects the survival, proliferation and differentiation of non-neuronal cells. Therefore, this study has examined whether extracellular Nm23H1 regulates nerve growth. We have immobilised recombinant Nm23H1 proteins to defined locations of culture plates, which were then seeded with explants of embryonic chick dorsal root ganglia (DRG) or dissociated adult rat DRG neurons. The substratum-bound extracellular Nm23H1 was stimulatory for neurite outgrowth from chick DRG explants in a concentration-dependent manner. On high concentrations of Nm23H1, chick DRG neurite outgrowth was extensive and effectively limited to the location of the Nm23H1, i.e. neuronal growth cones turned away from adjacent collagen-coated substrata. Nm23H1-coated substrata also significantly enhanced rat DRG neuronal cell adhesion and neurite outgrowth in comparison to collagen-coated substrata. These effects were independent of NGF supplementation. Recombinant Nm23H1 (H118F), which does not possess NDP kinase activity, exhibited the same activity as the wild-type protein. Hence, a novel neuro-stimulatory activity for extracellular Nm23H1 has been identified in vitro, which may function in developing neuronal systems. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Gene Therapy for Neuropathic Pain by Silencing of TNF-α Expression with Lentiviral Vectors Targeting the Dorsal Root Ganglion in Mice

    Science.gov (United States)

    Ogawa, Nobuhiro; Kawai, Hiromichi; Terashima, Tomoya; Kojima, Hideto; Oka, Kazuhiro; Chan, Lawrence; Maegawa, Hiroshi

    2014-01-01

    Neuropathic pain can be a debilitating condition. Many types of drugs that have been used to treat neuropathic pain have only limited efficacy. Recent studies indicate that pro-inflammatory mediators including tumor necrosis factor α (TNF-α) are involved in the pathogenesis of neuropathic pain. In the present study, we engineered a gene therapy strategy to relieve neuropathic pain by silencing TNF-α expression in the dorsal root ganglion (DRG) using lentiviral vectors expressing TNF short hairpin RNA1-4 (LV-TNF-shRNA1-4) in mice. First, based on its efficacy in silencing TNF-α in vitro, we selected shRNA3 to construct LV-TNF-shRNA3 for in vivo study. We used L5 spinal nerve transection (SNT) mice as a neuropathic pain model. These animals were found to display up-regulated mRNA expression of activating transcription factor 3 (ATF3) and neuropeptide Y (NPY), injury markers, and interleukin (IL)-6, an inflammatory cytokine in the ipsilateral L5 DRG. Injection of LV-TNF-shRNA3 onto the proximal transected site suppressed significantly the mRNA levels of ATF3, NPY and IL-6, reduced mechanical allodynia and neuronal cell death of DRG neurons. These results suggest that lentiviral-mediated silencing of TNF-α in DRG relieves neuropathic pain and reduces neuronal cell death, and may constitute a novel therapeutic option for neuropathic pain. PMID:24642694

  8. Intrinsic architecture underlying the relations among the default, dorsal attention, and frontoparietal control networks of the human brain.

    Science.gov (United States)

    Spreng, R Nathan; Sepulcre, Jorge; Turner, Gary R; Stevens, W Dale; Schacter, Daniel L

    2013-01-01

    Human cognition is increasingly characterized as an emergent property of interactions among distributed, functionally specialized brain networks. We recently demonstrated that the antagonistic "default" and "dorsal attention" networks--subserving internally and externally directed cognition, respectively--are modulated by a third "frontoparietal control" network that flexibly couples with either network depending on task domain. However, little is known about the intrinsic functional architecture underlying this relationship. We used graph theory to analyze network properties of intrinsic functional connectivity within and between these three large-scale networks. Task-based activation from three independent studies were used to identify reliable brain regions ("nodes") of each network. We then examined pairwise connections ("edges") between nodes, as defined by resting-state functional connectivity MRI. Importantly, we used a novel bootstrap resampling procedure to determine the reliability of graph edges. Furthermore, we examined both full and partial correlations. As predicted, there was a higher degree of integration within each network than between networks. Critically, whereas the default and dorsal attention networks shared little positive connectivity with one another, the frontoparietal control network showed a high degree of between-network interconnectivity with each of these networks. Furthermore, we identified nodes within the frontoparietal control network of three different types--default-aligned, dorsal attention-aligned, and dual-aligned--that we propose play dissociable roles in mediating internetwork communication. The results provide evidence consistent with the idea that the frontoparietal control network plays a pivotal gate-keeping role in goal-directed cognition, mediating the dynamic balance between default and dorsal attention networks.

  9. Uso terapêutico da radiofrequência pulsátil no gânglio dorsal da raiz de L2 na lombalgia discogênica Uso terapéutico de la radiofrecuencia pulsátil en el ganglio dorsal de la raíz de L2 en la lumbalgia discogénica Pulsed radiofrequency on L2 dorsal root ganglion as a therapeutic method for lumbar discogenic pain

    Directory of Open Access Journals (Sweden)

    Fabrício Dias Assis

    2009-06-01

    Full Text Available OBJETIVO: Avaliar a eficácia da radiofrequência pulsátil sobre o gânglio da raiz dorsal de L2 no tratamento dos pacientes com lombalgia discogênica. MÉTODOS: Realizou-se análise retrospectiva de 50 pacientes portadores de lombalgia crônica discogênica atendidos no período de janeiro de 2004 a julho de 2007. O processo diagnóstico foi constituído por exame físico, ressonância magnética e bloqueio diagnóstico do gânglio da raiz dorsal de L2. Todos os pacientes foram submetidos à radiofrequência pulsátil no gânglio da raiz dorsal de L2 e acompanhados por, no mínimo, 12 meses. A intensidade de dor foi medida pela escala visual analógica (EVA de dor. RESULTADOS: A análise estatística mostrou melhora significativa da intensidade de dor (pOBJETIVO: evaluar la eficacia de la radiofrecuencia pulsátil sobre el ganglio de la raíz dorsal de L2 en el tratamiento de los pacientes con lumbalgia discogénica. MÉTODOS: fue realizado un análisis retrospectivo de 50 pacientes portadores de lumbalgia crónica discogénica, atendidos en el periodo de Enero de 2004 a Julio de 2007. El proceso diagnóstico constó de un examen físico, resonancia magnética y bloqueo diagnóstico del ganglio de la raíz dorsal de L2. Todos los pacientes fueron sometidos a la radiofrecuencia pulsátil en el ganglio de la raíz dorsal de L2 y seguidos por 12 meses, como mínimo. La intensidad del dolor fue medida por la escala visual analógica del dolor. RESULTADOS: el análisis estadístico mostró mejoría significativa de la intensidad del dolor (pOBJECTIVE: to evaluate the effectiveness of pulsate radio-frequency on L2 dorsal root ganglion for chronic discogenic low back pain. Of L2 in the treatment of the patient with discogenic low back pain. METHODS: Between January 2004 and July 2007, 50 patients with diagnosis of low back discogenic pain were retrospectively assessed based on physical examination, magnetic resonance imaging findings and selective L

  10. Blood supply to human malignant melanoma xenografts in the mouse dorsal window chamber : Abstract

    OpenAIRE

    Øye, Kathrine Sørestrand

    2006-01-01

    The effectiveness of non-surgical treatments is depending on the oxygenation status of the tumor. The oxygenation status is determined in part by whether the bloodsupply is arterial or venous in origin, if the blood is distributed homogenously troughout the tumornetwork, and if there is fluctuations in the bloodstream. We have looked at some of these parameters for the malignant melanoma xenographt, using the mouse dorsal window chamber and a fluorecent cell line. We have also developed a tec...

  11. Acute morphine activates satellite glial cells and up-regulates IL-1β in dorsal root ganglia in mice via matrix metalloprotease-9

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    Berta Temugin

    2012-03-01

    Full Text Available Abstract Background Activation of spinal cord glial cells such as microglia and astrocytes has been shown to regulate chronic opioid-induced antinociceptive tolerance and hyperalgesia, due to spinal up-regulation of the proinflammatory cytokines such as interleukin-1 beta (IL-1β. Matrix metalloprotease-9 (MMP-9 has been implicated in IL-1β activation in neuropathic pain. However, it is unclear whether acute opioid treatment can activate glial cells in the peripheral nervous system. We examined acute morphine-induced activation of satellite glial cells (SGCs and up-regulation of IL-1β in dorsal root ganglia (DRGs, and further investigated the involvement of MMP-9 in these opioid-induced peripheral changes. Results Subcutaneous morphine injection (10 mg/kg induced robust peripheral glial responses, as evidenced by increased GFAP expression in DRGs but not in spinal cords. The acute morphine-induced GFAP expression is transient, peaking at 2 h and declining after 3 h. Acute morphine treatment also increased IL-1β immunoreactivity in SGCs and IL-1β activation in DRGs. MMP-9 and GFAP are expressed in DRG neurons and SGCs, respectively. Confocal analysis revealed a close proximity of MMP-9 and GFAP immunostaining. Importantly, morphine-induced DRG up-regulation of GFAP expression and IL-1β activation was abolished after Mmp9 deletion or naloxone pre-treatment. Finally, intrathecal injections of IL-1β-selective siRNA not only reduced DRG IL-1β expression but also prolonged acute morphine-induced analgesia. Conclusions Acute morphine induces opioid receptors- and MMP-9-dependent up-regulation of GFAP expression and IL-1β activation in SGCs of DRGs. MMP-9 could mask and shorten morphine analgesia via peripheral neuron-glial interactions. Targeting peripheral glial activation might prolong acute opioid analgesia.

  12. Regulation of the spontaneous augmentation of Na(V)1.9 in mouse dorsal root ganglion neurons: effect of PKA and PKC pathways.

    Science.gov (United States)

    Kakimura, Jun-ichi; Zheng, Taixing; Uryu, Noriko; Ogata, Nobukuni

    2010-03-19

    Sensory neurons in the dorsal root ganglion express two kinds of tetrodotoxin resistant (TTX-R) isoforms of voltage-gated sodium channels, Na(V)1.8 and Na(V)1.9. These isoforms play key roles in the pathophysiology of chronic pain. Of special interest is Na(V)1.9: our previous studies revealed a unique property of the Na(V)1.9 current, i.e., the Na(V)1.9 current shows a gradual and notable up-regulation of the peak amplitude during recording ("spontaneous augmentation of Na(V)1.9"). However, the mechanism underlying the spontaneous augmentation of Na(V)1.9 is still unclear. In this study, we examined the effects of protein kinases A and C (PKA and PKC), on the spontaneous augmentation of Na(V)1.9. The spontaneous augmentation of the Na(V)1.9 current was significantly suppressed by activation of PKA, whereas activation of PKA did not affect the voltage dependence of inactivation for the Na(V)1.9 current. On the contrary, the finding that activation of PKC can affect the voltage dependence of inactivation for Na(V)1.9 in the perforated patch recordings, where the augmentation does not occur, suggests that the effects of PMA are independent of the augmentation process. These results indicate that the spontaneous augmentation of Na(V)1.9 was regulated directly by PKA, and indirectly by PKC.

  13. Comparative study of the distribution of the alpha-subunits of voltage-gated sodium channels in normal and axotomized rat dorsal root ganglion neurons.

    Science.gov (United States)

    Fukuoka, Tetsuo; Kobayashi, Kimiko; Yamanaka, Hiroki; Obata, Koichi; Dai, Yi; Noguchi, Koichi

    2008-09-10

    We compared the distribution of the alpha-subunit mRNAs of voltage-gated sodium channels Nav1.1-1.3 and Nav1.6-1.9 and a related channel, Nax, in histochemically identified neuronal subpopulations of the rat dorsal root ganglia (DRG). In the naïve DRG, the expression of Nav1.1 and Nav1.6 was restricted to A-fiber neurons, and they were preferentially expressed by TrkC neurons, suggesting that proprioceptive neurons possess these channels. Nav1.7, -1.8, and -1.9 mRNAs were more abundant in C-fiber neurons compared with A-fiber ones. Nax was evenly expressed in both populations. Although Nav1.8 and -1.9 were preferentially expressed by TrkA neurons, other alpha-subunits were expressed independently of TrkA expression. Actually, all IB4(+) neurons expressed both Nav1.8 and -1.9, and relatively limited subpopulations of IB4(+) neurons (3% and 12%, respectively) expressed Nav1.1 and/or Nav1.6. These findings provide useful information in interpreting the electrophysiological characteristics of some neuronal subpopulations of naïve DRG. After L5 spinal nerve ligation, Nav1.3 mRNA was up-regulated mainly in A-fiber neurons in the ipsilateral L5 DRG. Although previous studies demonstrated that nerve growth factor (NGF) and glial cell-derived neurotrophic factor (GDNF) reversed this up-regulation, the Nav1.3 induction was independent of either TrkA or GFRalpha1 expression, suggesting that the induction of Nav1.3 may be one of the common responses of axotomized DRG neurons without a direct relationship to NGF/GDNF supply. (c) 2008 Wiley-Liss, Inc.

  14. Glycosylation alters steady-state inactivation of sodium channel Nav1.9/NaN in dorsal root ganglion neurons and is developmentally regulated.

    Science.gov (United States)

    Tyrrell, L; Renganathan, M; Dib-Hajj, S D; Waxman, S G

    2001-12-15

    Na channel NaN (Na(v)1.9) produces a persistent TTX-resistant (TTX-R) current in small-diameter neurons of dorsal root ganglia (DRG) and trigeminal ganglia. Na(v)1.9-specific antibodies react in immunoblot assays with a 210 kDa protein from the membrane fractions of adult DRG and trigeminal ganglia. The size of the immunoreactive protein is in close agreement with the predicted Na(v)1.9 theoretical molecular weight of 201 kDa, suggesting limited glycosylation of this channel in adult tissues. Neonatal rat DRG membrane fractions, however, contain an additional higher molecular weight immunoreactive protein. Reverse transcription-PCR analysis did not show additional longer transcripts that could encode the larger protein. Enzymatic deglycosylation of the membrane preparations converted both immunoreactive proteins into a single faster migrating band, consistent with two states of glycosylation of Na(v)1.9. The developmental change in the glycosylation state of Na(v)1.9 is paralleled by a developmental change in the gating of the persistent TTX-R Na(+) current attributable to Na(v)1.9 in native DRG neurons. Whole-cell patch-clamp analysis demonstrates that the midpoint of steady-state inactivation is shifted 7 mV in a hyperpolarized direction in neonatal (postnatal days 0-3) compared with adult DRG neurons, although there is no significant difference in activation. Pretreatment of neonatal DRG neurons with neuraminidase causes an 8 mV depolarizing shift in the midpoint of steady-state inactivation of Na(v)1.9, making it indistinguishable from that of adult DRG neurons. Our data show that extensive glycosylation of rat Na(v)1.9 is developmentally regulated and changes a critical property of this channel in native neurons.

  15. Role of PAF receptor in proinflammatory cytokine expression in the dorsal root ganglion and tactile allodynia in a rodent model of neuropathic pain.

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    Shigeo Hasegawa

    Full Text Available BACKGROUND: Neuropathic pain is a highly debilitating chronic pain following damage to peripheral sensory neurons and is often resistant to all treatments currently available, including opioids. We have previously shown that peripheral nerve injury induces activation of cytosolic phospholipase A(2 (cPLA(2 in injured dorsal root ganglion (DRG neurons that contribute to tactile allodynia, a hallmark of neuropathic pain. However, lipid mediators downstream of cPLA(2 activation to produce tactile allodynia remain to be determined. PRINCIPAL FINDINGS: Here we provide evidence that platelet-activating factor (PAF is a potential candidate. Pharmacological blockade of PAF receptors (PAFRs reduced the development and expression of tactile allodynia following nerve injury. The expression of PAFR mRNA was increased in the DRG ipsilateral to nerve injury, which was seen mainly in macrophages. Furthermore, mice lacking PAFRs showed a reduction of nerve injury-induced tactile allodynia and, interestingly, a marked suppression of upregulation of tumor necrosis factor alpha (TNFalpha and interleukin-1beta (IL-1beta expression in the injured DRG, crucial proinflammatory cytokines involved in pain hypersensitivity. Conversely, a single injection of PAF near the DRG of naïve rats caused a decrease in the paw withdrawal threshold to mechanical stimulation in a dose-dependent manner and an increase in the expression of mRNAs for TNFalpha and IL-1beta, both of which were inhibited by pretreatment with a PAFR antagonist. CONCLUSIONS: Our results indicate that the PAF/PAFR system has an important role in production of TNFalpha and IL-1beta in the DRG and tactile allodynia following peripheral nerve injury and suggest that blocking PAFRs may be a viable therapeutic strategy for treating neuropathic pain.

  16. Paclitaxel-induced painful neuropathy is associated with changes in mitochondrial bioenergetics, glycolysis, and an energy deficit in dorsal root ganglia neurons.

    Science.gov (United States)

    Duggett, Natalie A; Griffiths, Lisa A; Flatters, Sarah J L

    2017-08-01

    Painful neuropathy is the major dose-limiting side effect of paclitaxel chemotherapy. Mitochondrial dysfunction and adenosine triphosphate (ATP) deficit have previously been shown in peripheral nerves of paclitaxel-treated rats, but the effects of paclitaxel in the dorsal root ganglia (DRGs) have not been explored. The aim of this study was to determine the bioenergetic status of DRG neurons following paclitaxel exposure in vitro and in vivo. Utilising isolated DRG neurons, we measured respiratory function under basal conditions and at maximal capacity, glycolytic function, and Adenosine diphosphate (ADP)/ATP levels at 3 key behavioural timepoints; prior to pain onset (day 7), peak pain severity and pain resolution. At day 7, maximal respiration and spare reserve capacity were significantly decreased in DRG neurons from paclitaxel-treated rats. This was accompanied by decreased basal ATP levels and unaltered ADP levels. At peak pain severity, respiratory function was unaltered, yet glycolytic function was significantly increased. Reduced ATP and unaltered ADP levels were also observed at the peak pain timepoint. All these effects in DRG neurons had dissipated by the pain resolution timepoint. None of these paclitaxel-evoked changes could be replicated from in vitro paclitaxel exposure to naive DRG neurons, demonstrating the impact of in vivo exposure and the importance of in vivo models. These data demonstrate the nature of mitochondrial dysfunction evoked by in vivo paclitaxel in the DRG for the first time. Furthermore, we have identified paclitaxel-evoked changes in the bioenergetics of DRG neurons, which result in a persistent energy deficit that is causal to the development and maintenance of paclitaxel-induced pain.

  17. A multicenter, prospective trial to assess the safety and performance of the spinal modulation dorsal root ganglion neurostimulator system in the treatment of chronic pain.

    Science.gov (United States)

    Liem, Liong; Russo, Marc; Huygen, Frank J P M; Van Buyten, Jean-Pierre; Smet, Iris; Verrills, Paul; Cousins, Michael; Brooker, Charles; Levy, Robert; Deer, Timothy; Kramer, Jeffery

    2013-01-01

    This multicenter prospective trial was conducted to evaluate the clinical performance of a new neurostimulation system designed to treat chronic pain through the electrical neuromodulation of the dorsal root ganglia (DRG) neurophysiologically associated with painful regions of the limbs and/or trunk. Thirty-two subjects were implanted with a novel neuromodulation device. Pain ratings during stimulation were followed up to six months and compared with baseline ratings. Subjects also completed two separate reversal periods in which stimulation was briefly stopped in order to establish the effects of the intervention. At all assessments, more than half of subjects reported pain relief of 50% or better. At six months postimplant, average overall pain ratings were 58% lower than baseline (p reduction in pain specific to back, leg, and foot regions were 57%, 70%, and 89%, respectively. When stimulation was discontinued for a short time, pain returned to baseline levels. Discrete coverage of hard-to-treat areas was obtained across a variety of anatomical pain distributions. Paresthesia intensity remained stable over time and there was no significant difference in the paresthesia intensity perceived during different body postures/positions (standing up vs. lying down). Results of this clinical trial demonstrate that neurostimulation of the DRG is a viable neuromodulatory technique for the treatment of chronic pain. Additionally, the capture of discrete painful areas such as the feet combined with stable paresthesia intensities across body positions suggest that this stimulation modality may allow more selective targeting of painful areas and reduce unwanted side-effects observed in traditional spinal cord stimulation (SCS). © 2013 International Neuromodulation Society.

  18. Dorsal root ganglion neurons with dichotomizing axons projecting to the hip joint and the knee skin in rats: possible mechanism of referred knee pain in hip joint disease.

    Science.gov (United States)

    Miura, Yoko; Ohtori, Seiji; Nakajima, Takayuki; Kishida, Shinji; Harada, Yoshitada; Takahashi, Kazuhisa

    2011-11-01

    Patients who have hip joint diseases sometimes complain of knee pain as well as hip joint area pain. However, the precise sensory innervation pattern and correlation of the sensory nerves of the hip joint and knee are unknown. The purpose of this study was to investigate dorsal root ganglion (DRG) neurons with dichotomizing axons projecting to both the hip joint and the knee skin in rats using double fluorescent labeling techniques, and to examine characteristics of the DRG neurons with dichotomizing axons using immunohistochemical staining for inflammatory neuropeptides such as calcitonin gene-related peptide (CGRP). For 20 rats, two kinds of neurotracers, Fluoro-Gold (FG) and 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanine perchlorate (DiI), were used in the double-labeling study. FG was injected into the left hip joint, and DiI was applied to the left medial portion of knee skin. Ten days after application, bilateral DRGs were harvested and immunohistochemically stained for CGRP. DRG neurons double labeled with FG and DiI were observed only from L2 to L4 on the left side. Approximately 1.6% of all DRG neurons innervating the hip joints had other axons that extended to the medial portion of knee skin, and 35% of double-labeled neurons were CGRP positive. Our results showed that the double-labeled neurons had peripheral axons that dichotomized into both the hip joint and the knee skin. CGRP-positive neurons of these dichotomizing fibers may play some role in the manifestation of referred knee pain with hip joint pain.

  19. Plasticity of dorsal root ganglion neurons in a rat model of post-infectious gut dysfunction: potential implication of nerve growth factor.

    Science.gov (United States)

    Jardí, Ferran; Fernández-Blanco, Joan A; Martínez, Vicente; Vergara, Patri

    2014-11-01

    Intestinal infections are suggested as a risk factor for the development of irritable bowel syndrome (IBS)-like visceral hypersensitivity. The mechanisms implicated might involve long-term changes in visceral afferents, with implication of nerve growth factor (NGF). We explored plastic changes in dorsal root ganglia (DRGs) receiving innervation from the gut and the potential implication of NGF in a rat model of IBS-like post-infectious gut dysfunction. Rats were infected with Trichinella spiralis larvae. Thirty days post-infection, inflammatory markers, including interleukins (ILs) and mucosal mast cell infiltration (rat mast cell protease II [RMCPII]), and NGF and TrkA expression was determined in the jejunum and colon (RT-qPCR). In the same animals, morphometry (neuronal body size) and NGF content (immunofluorescence) were assessed in thoracolumbar DRG neurons. In infected animals, a low-grade inflammatory-like response, characterized by up-regulated levels of RMCPII and IL-6, was observed in the jejunum and colon. TrkA expression was increased in the jejunum, whereas the colon showed a slight reduction. NGF levels remained unaltered regardless the gut region. Overall, the mean cross-sectional area of DRG neurons was increased in T. spiralis-infected animals, with a reduction in both TrkA and NGF staining. Results suggest that during T. spiralis infection in rats, there is a remodeling of sensory afferents that might imply a NGF-mediated mechanism. Plastic changes in sensory afferents might mediate the long-lasting functional alterations that characterize this model of IBS. Similar mechanisms might be operating in patients with post-infectious-IBS.

  20. The effects of neuroleptics on the GABA-induced Cl- current in rat dorsal root ganglion neurons: differences between some neuroleptics.

    Science.gov (United States)

    Yokota, Kenjiro; Tatebayashi, Hideharu; Matsuo, Tadashi; Shoge, Takashi; Motomura, Haruhiko; Matsuno, Toshiyuki; Fukuda, Akira; Tashiro, Nobutada

    2002-03-01

    1. Several neuroleptics inhibited the 3 microM gamma-aminobutyric acid induced-chloride current (GABA-current) on dissociated rat dorsal root ganglion neurons in whole-cell patch-clamp investigations. 2. The IC(50) for clozapine, zotepine, olanzapine, risperidone and chlorpromazine were 6.95, 18.26, 20.30, 106.01 and 114.56 microM, respectively. The values for the inhibitory effects of neuroleptics on the GABA (3 microM)-current, which were calculated by the fitting Hill's equations where the concentrations represent the mean therapeutic blood concentrations, were ranked clozapine>zotepine>chlorpromazine>olanzapine>risperidone. These inhibitory effects, weighted with the therapeutic concentrations of neuroleptics, were correlated with the clinical incidences of seizure during treatment with neuroleptics. 3. Clozapine reduced the picrotoxin-inhibiton, and may compete with a ligand of the t-butylbicyclophosphorothionate (TBPS) binding site. 4. Haloperidol and quetiapine did not affect the peak amplitude of the GABA (3 microM)-current. However, haloperidol reduced the clozapine-inhibition, and may antagonize ligand binding to TBPS binding site. 5. Neuroleptics including haloperidol and quetiapine enhanced the desensitization of the GABA (3 microM)-current. However, haloperidol and quetiapine at 100 microM inhibited the desensitization at the beginning of application. 6. Blonanserin (AD-5423) at 30 and 50 microM potentiated the GABA (3 microM)-current to 170.1+/-6.9 and 192.0+/-10.6% of the control current, respectively. Blonanserin shifted GABA concentration-response curve leftward. Blonanserin only partly negatively interacted with diazepam. The blonanserin-potentiation was not reversed by flumazenil. Blonanserin is not a benzodiazepine receptor agonist. 7. The various effects of neuroleptics on the GABA-current may be related to the clinical effects including modifying the seizure threshold.

  1. The effects of neuroleptics on the GABA-induced Cl− current in rat dorsal root ganglion neurons: differences between some neuroleptics

    Science.gov (United States)

    Yokota, Kenjiro; Tatebayashi, Hideharu; Matsuo, Tadashi; Shoge, Takashi; Motomura, Haruhiko; Matsuno, Toshiyuki; Fukuda, Akira; Tashiro, Nobutada

    2002-01-01

    Several neuroleptics inhibited the 3 μM γ-aminobutyric acid induced-chloride current (GABA-current) on dissociated rat dorsal root ganglion neurons in whole-cell patch-clamp investigations. The IC50 for clozapine, zotepine, olanzapine, risperidone and chlorpromazine were 6.95, 18.26, 20.30, 106.01 and 114.56 μM, respectively. The values for the inhibitory effects of neuroleptics on the GABA (3 μM)-current, which were calculated by the fitting Hill's equations where the concentrations represent the mean therapeutic blood concentrations, were ranked clozapine>zotepine>chlorpromazine>olanzapine>risperidone. These inhibitory effects, weighted with the therapeutic concentrations of neuroleptics, were correlated with the clinical incidences of seizure during treatment with neuroleptics. Clozapine reduced the picrotoxin-inhibiton, and may compete with a ligand of the t-butylbicyclophosphorothionate (TBPS) binding site. Haloperidol and quetiapine did not affect the peak amplitude of the GABA (3 μM)-current. However, haloperidol reduced the clozapine-inhibition, and may antagonize ligand binding to TBPS binding site. Neuroleptics including haloperidol and quetiapine enhanced the desensitization of the GABA (3 μM)-current. However, haloperidol and quetiapine at 100 μM inhibited the desensitization at the beginning of application. Blonanserin (AD-5423) at 30 and 50 μM potentiated the GABA (3 μM)-current to 170.1±6.9 and 192.0±10.6% of the control current, respectively. Blonanserin shifted GABA concentration-response curve leftward. Blonanserin only partly negatively interacted with diazepam. The blonanserin-potentiation was not reversed by flumazenil. Blonanserin is not a benzodiazepine receptor agonist. The various effects of neuroleptics on the GABA-current may be related to the clinical effects including modifying the seizure threshold. PMID:11906969

  2. Ca2+ channel currents in dorsal root ganglion neurons of P/Q-type voltage-gated Ca2+ channel mutant mouse, rolling mouse Nagoya.

    Science.gov (United States)

    Fukumoto, Nao; Kitamura, Naoki; Niimi, Kimie; Takahashi, Eiki; Itakura, Chitoshi; Shibuya, Izumi

    2012-07-01

    The role of the P/Q-type voltage-gated Ca(2+) channels (VGCCs) in release of neurotransmitters involved in nociception is not fully understood. Rolling mouse Nagoya (tg(rol)), a P/Q-type channel mutant mouse, expresses P/Q-type VGCC whose activation curve has a higher half activation potential and a smaller slope factor than the wild type channel. We previously reported that tg(rol) mice showed hypoalgesic responses to noxious stimuli. In this study, we examined the VGCC current in dorsal root ganglion (DRG) neurons by the whole-cell patch-clamp method. Both ω-agatoxin IVA (0.1 μM) and ω-conotoxin GVIA (1 μM) inhibited the VGCC current by about 40-50% in both the homozygous tg(rol) (tg(rol)/tg(rol)) and wild type (+/+) mice. The voltage-activation relationships of the total VGCC current and the ω-agatoxin IVA-sensitive component in the tg(rol)/tg(rol) mice shifted positively compared to the +/+ mice, whereas that sensitive to the ω-conotoxin GVIA was not different between the two genotypes. The time constant of activation of the VGCC current at -20 mV was longer in the tg(rol)/tg(rol) mice than in the +/+ mice. These changes in the properties of the VGCC in the tg(rol)/tg(rol) mouse may reduce the amount of the released neurotransmitters and account for the hypoalgesic responses. Copyright © 2012 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  3. Modulation of dragon's blood on tetrodotoxin-resistant sodium currents in dorsal root ganglion neurons and identification of its material basis for efficacy.

    Science.gov (United States)

    Liu, Xiangming; Chen, Su; Zhang, Yuxia; Zhang, Fan

    2006-06-01

    To clarify the modulation of dragon's blood on the tetrodotoxin-resistant (TTX-R) sodium currents in dorsal root ganglion (DRG) neurons and explore its corresponding material basis for the efficacy, using whole-cell patch clamp technique, the effects of dragon's blood and the combined effects of three components (cochinchinenin A, cochinchinenin B, and loureirin B) extracted from dragon's blood on the TTX-R sodium currents in acute-isolated DRG neurons of rats were observed. According to the operational definition of material basis for the efficacy of TCM established, the material basis of the modulation on the TTX-R sodium currents in DRG neurons of dragon's blood was judged from the experimental results. The drug interaction equation of Greco et al. was used to assess the interaction of the three components extracted from dragon's blood. This investigation demonstrated that dragon's blood suppressed the peak TTX-R sodium currents in a dose-dependent way and affected the activations of TTX-R sodium currents. The effects of the combination of cochinchinenin A, cochinchinenin B, and loureirin B were in good agreement with those of dragon's blood. Although the three components used alone could modulate TTX-R sodium currents, the concentrations of the three components used alone were respectively higher than those used in combination when the inhibition rates on the TTX-R sodium currents of them used alone and in combination were the same. The combined effects of the three components were synergistic. These results suggested that the interference with pain messages caused by the modulation of dragon's blood on TTX-R sodium currents in DRG neurons may explain some of the analgesic effect of dragon's blood and the corresponding material basis for the efficacy is the combination of cochinchinenin A, cochinchinenin B, and loureirin B.

  4. Long-term activation of group I metabotropic glutamate receptors increases functional TRPV1-expressing neurons in mouse dorsal root ganglia

    Directory of Open Access Journals (Sweden)

    Takayoshi eMasuoka

    2016-03-01

    Full Text Available Damaged tissues release glutamate and other chemical mediators for several hours. These chemical mediators contribute to modulation of pruritus and pain. Herein, we investigated the effects of long-term activation of excitatory glutamate receptors on functional expression of transient receptor potential vaniloid type 1 (TRPV1 in dorsal root ganglion (DRG neurons and then on thermal pain behavior. In order to detect the TRPV1-mediated responses in cultured DRG neurons, we monitored intracellular calcium responses to capsaicin, a TRPV1 agonist, with Fura-2. Long-term (4 h treatment with glutamate receptor agonists (glutamate, quisqualate or DHPG increased the proportion of neurons responding to capsaicin through activation of metabotropic glutamate receptor mGluR1, and only partially through the activation of mGluR5; engagement of these receptors was evident in neurons responding to allylisothiocyanate (AITC, a transient receptor potential ankyrin type 1 (TRPA1 agonist. Increase in the proportion was suppressed by phospholipase C, protein kinase C, mitogen/extracellular signal-regulated kinase, p38 mitogen-activated protein kinase or transcription inhibitors. Whole-cell recording was performed to record TRPV1-mediated membrane current; TRPV1 current density significantly increased in the AITC-sensitive neurons after the quisqualate treatment. To elucidate the physiological significance of this phenomenon, a hot plate test was performed. Intraplantar injection of quisqualate or DHPG induced heat hyperalgesia that lasted for 4 h post injection. This chronic hyperalgesia was attenuated by treatment with either mGluR1 or mGluR5 antagonists. These results suggest that long-term activation of mGluR1/5 by peripherally released glutamate may increase the number of neurons expressing functional TRPV1 in DRG, which may be strongly associated with chronic hyperalgesia.

  5. Pain-related behavior and the characteristics of dorsal-root ganglia in a rat model of hip osteoarthritis induced by mono-iodoacetate.

    Science.gov (United States)

    Miyamoto, Shuichi; Nakamura, Junichi; Ohtori, Seiji; Orita, Sumihisa; Nakajima, Takayuki; Omae, Takanori; Hagiwara, Shigeo; Takazawa, Makoto; Suzuki, Miyako; Suzuki, Takane; Takahashi, Kazuhisa

    2017-07-01

    The principal aim of this study was to clarify the time course of pain-related behavior and pain-related sensory innervation in a rat model of hip osteoarthritis (OA) induced by intra-articular injection of mono-iodoacetate (MIA). Using 6-week-old male Sprague Dawley rats, 25 μl of sterile saline of 1% Fluoro-Gold solution (FG) (control group; n = 30) and 25 μl of sterile saline of 1% FG with 2 mg of MIA (MIA group; n = 30) was injected into the right hip joints. Gait function was evaluated using a CatWalk system after 7, 14, 28, 42, and 56 days (n = 5, respectively). Neurons in the dorsal root ganglion (DRG) between L1 and L5 were immunostained for calcitonin gene-related peptide (CGRP) and activating transcription factor-3 (ATF3). Gait analysis revealed the mean six parameters of hind paws at all time points were significantly lower in the MIA group (p = 0.05). The number of CGRP-immunoreactive (-IR) DRG neurons was significantly increased on days 7, 14, 28, and 42 peaking at 14 days in the MIA group. By contrast, expression of ATF3-IR in FG-labeled DRG neurons was significantly increased on days 42 and 57. The FG-labeled DRG neurons were distributed between L1 and L5, mainly at the L4 level. Pain-related behavior indicated by gait disturbance was observed in a MIA model of hip OA in rat. Early elevation of CGRP expression and late expression of ATF-3 were demonstrated in DRG neurons, possibly reflecting inflammatory pain and neuropathic pain in hip OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1424-1430, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  6. Pericellular Griffonia simplicifolia I isolectin B4-binding ring structures in the dorsal root ganglia following peripheral nerve injury in rats.

    Science.gov (United States)

    Li, L; Zhou, X F

    2001-10-22

    Patients with a peripheral nerve injury often suffer from persistent chronic pain, but the underlying mechanism remains largely unknown. The persistent nature of the pain suggests injury-induced profound structural changes along the sensory pathways. In the present study, using the plant Griffonia simplicifolia I isolectin B4 (IB4) as a marker for nonpeptidergic small sensory neurons, we sought to examine whether these neurons sprout in the dorsal root ganglia (DRG) in response to peripheral nerve injury. The lumbar 5 (L5) spinal nerve was transected, and rats were allowed to survive for varying lengths of time before IB4 histology was performed. We found that a subpopulation of IB4-positive sensory neurons sprouted robustly after spinal nerve injury. Twelve weeks after spinal nerve injury, the IB4-positive ring structures became dramatic and encircled both large and small neurons in the DRG. The aberrant sprouting of small sensory neurons was also demonstrated by retrograde labeling. The processes of satellite cells surrounding large sensory neurons also became IB4 positive, and 87.8% of perineuronal IB4-positive ring structures intermingled and/or coexpressed with glial fibrillary acidic protein-positive satellite cells. Thus, the sprouting axons of IB4-positive neurons were intermingled with IB4-positive satellite cells, forming perineuronal ring structures surrounding large-diameter neurons. Ultrastructural examinations further confirmed that IB4-positive nerve terminals were entangled with satellite cells and IB4-negative unmyelinated sprouting fibers around sensory neurons. These studies have provided the first evidence that a subpopulation of IB4-binding small sensory neurons sprouts and forms perineuronal ring structures together with IB4-positive satellite cells in response to nerve injury. The significance of the sprouting of IB4-positive neurons remains to be determined. Copyright 2001 Wiley-Liss, Inc.

  7. Extracellular Nm23H1 stimulates neurite outgrowth from dorsal root ganglia neurons in vitro independently of nerve growth factor supplementation or its nucleoside diphosphate kinase activity

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    Wright, K.T. [Keele University at the RJAH Orthopaedic Hospital, Oswestry, Shropshire (United Kingdom); Seabright, R.; Logan, A. [Neuropharmacology and Neurobiology, School of Clinical and Experimental Medicine, Birmingham University, Birmingham (United Kingdom); Lilly, A.J.; Khanim, F.; Bunce, C.M. [Biosciences, Birmingham University, Birmingham (United Kingdom); Johnson, W.E.B., E-mail: w.e.johnson@aston.ac.uk [Life and Health Sciences, Aston University, Birmingham (United Kingdom)

    2010-07-16

    Research highlights: {yields} Extracellular Nm23H1 stimulates nerve growth. {yields} Extracellular Nm23H1 provides pathfinding cues to growth cones. {yields} The neurotrophic activity of Nm23H1 is independent of NDP kinase activity. {yields} The neurotrophic activity of Nm23H1 is independent of NGF. -- Abstract: The nucleoside diphosphate (NDP) kinase, Nm23H1, is a highly expressed during neuronal development, whilst induced over-expression in neuronal cells results in increased neurite outgrowth. Extracellular Nm23H1 affects the survival, proliferation and differentiation of non-neuronal cells. Therefore, this study has examined whether extracellular Nm23H1 regulates nerve growth. We have immobilised recombinant Nm23H1 proteins to defined locations of culture plates, which were then seeded with explants of embryonic chick dorsal root ganglia (DRG) or dissociated adult rat DRG neurons. The substratum-bound extracellular Nm23H1 was stimulatory for neurite outgrowth from chick DRG explants in a concentration-dependent manner. On high concentrations of Nm23H1, chick DRG neurite outgrowth was extensive and effectively limited to the location of the Nm23H1, i.e. neuronal growth cones turned away from adjacent collagen-coated substrata. Nm23H1-coated substrata also significantly enhanced rat DRG neuronal cell adhesion and neurite outgrowth in comparison to collagen-coated substrata. These effects were independent of NGF supplementation. Recombinant Nm23H1 (H118F), which does not possess NDP kinase activity, exhibited the same activity as the wild-type protein. Hence, a novel neuro-stimulatory activity for extracellular Nm23H1 has been identified in vitro, which may function in developing neuronal systems.

  8. Antinociceptive Effects of AGAP, a Recombinant Neurotoxic Polypeptide: Possible Involvement of the Tetrodotoxin-Resistant Sodium Channels in Small Dorsal Root Ganglia Neurons

    Science.gov (United States)

    Li, Chun-Li; Liu, Xi-Fang; Li, Gui-Xia; Ban, Meng-qi; Chen, Jian-Zhao; Cui, Yong; Zhang, Jing-Hai; Wu, Chun-Fu

    2016-01-01

    Antitumor-analgesic peptide (AGAP) is a novel recombinant polypeptide. The primary study showed that AGAP 1.0 mg/kg exhibited strong analgesic and antitumor effects. The tail vein administration of AGAP potently reduced pain behaviors in mice induced by intraplantar injection of formalin or intraperitoneal injection of acetic acid, without affecting basal pain perception. To further assess the mechanisms of AGAP, the effects of AGAP on sodium channels were assessed using the whole-cell patch clamp recordings in dorsal root ganglia (DRG) neurons. The results showed that AGAP (3–1000 nM) inhibited the sodium currents in small-diameter DRG neurons in a dose-dependent manner. 1000 nM AGAP could inhibit the current density-voltage relationship curve of sodium channels in a voltage-dependent manner and negatively shift the activation curves. 1000 nM AGAP could reduce the tetrodotoxin-resistant (TTX-R) sodium currents by 42.8% in small-diameter DRG neurons. Further analysis revealed that AGAP potently inhibited NaV1.8 currents by 59.4%, and negatively shifted the activation and inactivation kinetics. 1000 nM AGAP also reduced the NaV1.9 currents by 33.7%, but had no significant effect on activation and inactivation kinetics. Thus, our results demonstrated that submicromolar concentrations of AGAP inhibited TTX-R sodium channel in rat small-diameter DRG neurons. It is concluded that these new results may better explain, at least in part, the analgesic properties of this polypeptide. PMID:28066245

  9. Regulation of the Spontaneous Augmentation of NaV1.9 in Mouse Dorsal Root Ganglion Neurons: Effect of PKA and PKC Pathways

    Science.gov (United States)

    Kakimura, Jun-ichi; Zheng, Taixing; Uryu, Noriko; Ogata, Nobukuni

    2010-01-01

    Sensory neurons in the dorsal root ganglion express two kinds of tetrodotoxin resistant (TTX-R) isoforms of voltage-gated sodium channels, NaV1.8 and NaV1.9. These isoforms play key roles in the pathophysiology of chronic pain. Of special interest is NaV1.9: our previous studies revealed a unique property of the NaV1.9 current, i.e., the NaV1.9 current shows a gradual and notable up-regulation of the peak amplitude during recording (“spontaneous augmentation of NaV1.9”). However, the mechanism underlying the spontaneous augmentation of NaV1.9 is still unclear. In this study, we examined the effects of protein kinases A and C (PKA and PKC), on the spontaneous augmentation of NaV1.9. The spontaneous augmentation of the NaV1.9 current was significantly suppressed by activation of PKA, whereas activation of PKA did not affect the voltage dependence of inactivation for the NaV1.9 current. On the contrary, the finding that activation of PKC can affect the voltage dependence of inactivation for NaV1.9 in the perforated patch recordings, where the augmentation does not occur, suggests that the effects of PMA are independent of the augmentation process. These results indicate that the spontaneous augmentation of NaV1.9 was regulated directly by PKA, and indirectly by PKC. PMID:20411123

  10. Antinociceptive effects of AGAP, a recombinant neurotoxic polypeptide: Possible involvement of the tetrodotoxin-resistant sodium channels in small dorsal root ganglia neurons

    Directory of Open Access Journals (Sweden)

    Li Chunli

    2016-12-01

    Full Text Available Antitumor-analgesic peptide(AGAP)is a novel recombinant polypeptide. The primary study showed that AGAP 1.0 mg/kg exhibited strong analgesic and antitumor effects. The tail vein administration of AGAP potently reduced pain behaviors in mice induced by intraplantar injection of formalin or intraperitoneal injection of acetic acid, without affecting basal pain perception. To further assess the mechanisms of AGAP, the effects of AGAP on sodium channels were assessed using the whole-cell patch clamp recordings in dorsal root ganglia (DRG neurons. The results showed that AGAP (3-1000 nM inhibited the sodium currents in small-diameter DRG neurons in a dose-dependent manner. 1000 nM AGAP could inhibit the current density-voltage relationship curve of sodium channels in a voltage-dependent manner and negatively shift the activation curves. 1000 nM AGAP could reduce the tetrodotoxin-resistant (TTX-R sodium currents by 42.8% in small-diameter DRG neurons. Further analysis revealed that AGAP potently inhibited NaV1.8 currents by 59.4%, and negatively shifted the activation and inactivation kinetics. 1000 nM AGAP also reduced the NaV1.9 currents by 33.7%, but had no significant effect on activation and inactivation kinetics. Thus, our results demonstrated that submicromolar concentrations of AGAP inhibited TTX-R sodium channel in rat small-diameter DRG neurons. It is concluded that these new results may better explain, at least in part, the analgesic properties of this polypeptide.

  11. Comparative study of voltage-gated sodium channel α-subunits in non-overlapping four neuronal populations in the rat dorsal root ganglion.

    Science.gov (United States)

    Fukuoka, Tetsuo; Noguchi, Koichi

    2011-06-01

    Voltage-gated sodium channel α-subunit (Nav) is the major determinant of neuronal electrophysiological characters. In order to compare the composition of Navs among neurochemically different neurons in the rat dorsal root ganglion (DRG), we examined the expression of Nav transcripts in four non-overlapping neuronal populations, with (+) or without (-) N52 immunoreactivity, a marker of neurons with myelinated axons, and TrkA mRNA identified by in situ hybridization histochemistry. Both N52-/TrkA+ and N52-/TrkA- populations had high levels of signals for Nav1.7, Nav1.8, and Nav1.9 mRNAs, but rarely expressed Nav1.1 or Nav1.6. There was no significant difference in these signals, suggesting that C-fiber peptidergic and non-peptidergic neurons have similar electrophysiological characters with regard to sodium currents. N52+/TrkA+ neurons (putative A-fiber nociceptors) had similar high levels of signals for Nav1.7 and Nav1.8, but a significantly lower level of Nav1.9 signals, as compared to N52- neurons. Although, almost no N52+/TrkA- neurons had Nav1.8 or Nav1.9, half of this population expressed Nav1.7 at similar levels to other three populations and the other half completely lacked this channel. These data suggest that Nav1.8 is a common channel for both C- and A-fiber nociceptors, and Nav1.9 is rather selective for C-fiber nociceptors. Nav1.7 is the most universal channel while some functionally unknown N52+/TrkA- subpopulation selectively lacks it. Copyright © 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  12. Cisplatin-induced neuropathic pain is mediated by upregulation of N-type voltage-gated calcium channels in dorsal root ganglion neurons.

    Science.gov (United States)

    Leo, Markus; Schmitt, Linda-Isabell; Erkel, Martin; Melnikova, Margarita; Thomale, Jürgen; Hagenacker, Tim

    2017-02-01

    Cisplatin is important in the treatment of various types of cancer. Although it is highly effective, it also has severe side effects, with neurotoxicity in dorsal root ganglion (DRG) neurons being one of the most common. The key mechanisms of neurotoxicity are still controversially discussed; however, disturbances of the calcium homeostasis in DRG neurons have been suggested to mediate cisplatin neurotoxicity. By using the whole-cell patch-clamp technique, immunostaining and behavioral experiments with Sprague-Dawley rats, we examined the influence of short- and long-term exposure to cisplatin on voltage-gated calcium channel (VGCC) currents (ICa(V)) in small DRG neurons. In vitro exposure to cisplatin reduced ICa(V) in a concentration-dependent manner (0.01-50μM; 13.8-77.3%; IC50 5.07μM). Subtype-specific measurements of VGCCs showed differential effects on ICa(V). While the ICa(V) of P/Q-, L- and T-type VGCCs were reduced, ICa(V) of N-type VGCCs were increased by 30.3% during depolarization to 0mV. Exposure of DRG neurons to cisplatin (0.5 or 5μM) for 24-48h in vitro significantly increased a CaMK II-mediated ICa(V) current density. Immunostaining and western blot analysis revealed an increase of N-type VGCC protein level in DRG neurons 24h after cisplatin exposure. Cisplatin-mediated activation of caspase-3 was prevented by inhibition of N-type VGCCs using Ɯ-conotoxin MVIIA. Behavioral experiments showed that Ɯ-conotoxin MVIIA treatment prevented neuropathic syndromes in vivo by inhibiting upregulation of the N-type protein level. Here we show evidence for the first time for a crucial role of N-type VGCC in the genesis of cisplatin-induced polyneuropathy. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Oxaliplatin-induced changes in expression of transient receptor potential channels in the dorsal root ganglion as a neuropathic mechanism for cold hypersensitivity.

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    Chukyo, Akiko; Chiba, Terumasa; Kambe, Toshie; Yamamoto, Ken; Kawakami, Kazuyoshi; Taguchi, Kyoji; Abe, Kenji

    2017-12-15

    Transient receptor potential (TRP) receptors are involved in the development of chemotherapy-induced peripheral neuropathic pain, which is a common side effect of selected chemotherapeutic agents such as oxaliplatin. However, the precise contribution of TRPs to this condition remains unknown. Cold hypersensitivity is the hallmark of oxaliplatin-induced neuropathy, so we used a preclinical model of oxaliplatin-induced cold hypersensitivity in rats to determine the effects of oxaliplatin on TRP channels. To this end, immunohistochemistry was used to examine TRP vanilloid 1 (TRPV1), TRP ankyrin 1 (TRPA1), and TRP melastatin 8 (TRPM8) expression in the rat dorsal root ganglion (DRG) after 4days of oxaliplatin treatment. Behavioral assessment using the acetone spray test showed that oxaliplatin significantly increased acute cold hypersensitivity after 4days of treatment. Double-staining immunohistochemistry showed that 4days after oxaliplatin treatment, there was increased co-expression of TRPA1 and TRPV1 in isolectin B4-positive small-sized DRG neurons, as well as a significant increase in the co-localization of TRPM8 and neurofilament 200 in medium-sized DRG neurons. In addition, in situ hybridization revealed that TRPV1 protein was co-expressed with TRPA1 mRNA on day 4 after oxaliplatin administration. Thus, at an early stage following oxaliplatin treatment there is an increased expression of TRPA1 and TRPV1 in small-sized DRG neurons and of TRPM8 in medium-sized DRG neurons. Collectively, these changes may contribute to the development of oxaliplatin-induced peripheral neuropathic pain. Copyright © 2017. Published by Elsevier Ltd.

  14. Regulation of the Spontaneous Augmentation of NaV1.9 in Mouse Dorsal Root Ganglion Neurons: Effect of PKA and PKC Pathways

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    Nobukuni Ogata

    2010-03-01

    Full Text Available Sensory neurons in the dorsal root ganglion express two kinds of tetrodotoxin resistant (TTX-R isoforms of voltage-gated sodium channels, NaV1.8 and NaV1.9. These isoforms play key roles in the pathophysiology of chronic pain. Of special interest is NaV1.9: our previous studies revealed a unique property of the NaV1.9 current, i.e., the NaV1.9 current shows a gradual and notable up-regulation of the peak amplitude during recording (“spontaneous augmentation of NaV1.9”. However, the mechanism underlying the spontaneous augmentation of NaV1.9 is still unclear. In this study, we examined the effects of protein kinases A and C (PKA and PKC, on the spontaneous augmentation of NaV1.9. The spontaneous augmentation of the NaV1.9 current was significantly suppressed by activation of PKA, whereas activation of PKA did not affect the voltage dependence of inactivation for the NaV1.9 current. On the contrary, the finding that activation of PKC can affect the voltage dependence of inactivation for NaV1.9 in the perforated patch recordings, where the augmentation does not occur, suggests that the effects of PMA are independent of the augmentation process. These results indicate that the spontaneous augmentation of NaV1.9 was regulated directly by PKA, and indirectly by PKC.

  15. Microstimulation of primary afferent neurons in the L7 dorsal root ganglia using multielectrode arrays in anesthetized cats: thresholds and recruitment properties

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    Gaunt, R. A.; Hokanson, J. A.; Weber, D. J.

    2009-10-01

    Current research in motor neural prosthetics has focused primarily on issues related to the extraction of motor command signals from the brain (e.g. brain-machine interfaces) to direct the motion of prosthetic limbs. Patients using these types of systems could benefit from a somatosensory neural interface that conveys natural tactile and kinesthetic sensations for the prosthesis. Electrical microstimulation within the dorsal root ganglia (DRG) has been proposed as one method to accomplish this, yet little is known about the recruitment properties of electrical microstimulation in activating nerve fibers in this structure. Current-controlled microstimulation pulses in the range of 1-15 µA (200 µs, leading cathodic pulse) were delivered to the L7 DRG in four anesthetized cats using penetrating microelectrode arrays. Evoked responses and their corresponding conduction velocities (CVs) were measured in the sciatic nerve with a 5-pole nerve cuff electrode arranged as two adjacent tripoles. It was found that in 76% of the 69 electrodes tested, the stimulus threshold was less than or equal to 3 µA, with the lowest recorded threshold being 1.1 µA. The CVs of afferents recruited at threshold had a bimodal distribution with peaks at 70 m s-1 and 85 m s-1. In 53% of cases, the CV of the response at threshold was slower (i.e. smaller diameter fiber) than the CVs of responses observed at increasing stimulation amplitudes. In summary, we found that microstimulation applied through penetrating microelectrodes in the DRG provides selective recruitment of afferent fibers from a range of sensory modalities (as identified by CVs) at very low stimulation intensities. We conclude that the DRG may serve as an attractive location from which to introduce surrogate somatosensory feedback into the nervous system.

  16. Activation of the RAGE/STAT3 Pathway in the Dorsal Root Ganglion Contributes to the Persistent Pain Hypersensitivity Induced by Lumbar Disc Herniation.

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    Zhang, Xin-Sheng; Li, Xiao; Luo, Hai-Jie; Huang, Zhu-Xi; Liu, Cui-Cui; Wan, Qing; Xu, Shu-Wei; Wu, Shao-Ling; Ke, Song-Jian; Ma, Chao

    2017-07-01

    Clinically, chronic low back pain and sciatica associated with lumbar disc herniation (LDH) is a common musculoskeletal disorder. Due to the unawareness of detailed mechanisms, it is difficult to get an effective therapy. The aim of the present study was to identify the role of the RAGE/STAT3 pathway in the dorsal root ganglion (DRG) on the formation and development of persistent pain hypersensitivity induced by LDH. Controlled animal study. University laboratory. After LDH induced by implantation of autologous nucleus pulposus (NP, harvested from animal tail) on the left L5 nerve root was established, mechanical thresholds and electrophysiological tests were conducted at relevant time points during an observation period of 28 days. Protein levels and localization of RAGE and p-STAT3 were performed by using Western blotting and immunohistochemistry, respectively. LDH induced persistent pain hypersensitivity, increased excitability of DRG neurons, and upregulated the expression of RAGE and p-STAT3 in the DRG. Consecutive injection of both RAGE antagonist FPS-ZM1 (i.t.) and STAT3 activity inhibitor S3I-201 (i.t.) inhibited the enhanced excitability of DRG neurons and mechanical allodynia induced by NP implantation. Furthermore, local knockdown of STAT3 by intrathecal injection of AAV-Cre-GFP into STAT3flox/flox mice markedly alleviated NP implantation-induced mechanical allodynia in mice. Importantly, the expression of p-STAT3 was colocalized with that of RAGE in the DRG and inhibition of RAGE with FPS-ZM1 prevented NP implantation-induced STAT3 activation. More underlying mechanism(s) of the role of the RAGE/STAT3 pathway on the formation and development of persistent pain hypersensitivity induced by LDH will be needed to be explored in future research. These findings suggest activation of the RAGE/STAT3 pathway plays a critical role in persistent pain induced by LDH, and this pathway may represent novel therapeutic targets for the treatment of LDH

  17. External root resorption: Different etiologies explained from the composition of the human root-close periodontal membrane

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    Inger Kjaer

    2013-01-01

    Full Text Available Introduction: This paper summarizes different conditions, which have a well-known influence on the resorption of tooth roots. It also highlights factors important for individual susceptibility to root resorption. Furthermore, the paper focuses on idiopathic root resorption where the provoking factor is not known. The Hypothesis: The several different disturbances causing root resorption can be either orthodontically provoked or acquired by trauma, virus or congenital diseases. It is presumed that all these conditions lead to inflammatory processes in the three main tissue layers, comprising the peri-root sheet. Evaluation of the Hypothesis: This paper explains how different etiologies behind root resorption and how different phenotypic traits in root resorption can be understood from immunohistochemical studies of the human periodontal membrane close to the root and thus, gain a new understanding of the phenomenon of root resorption.

  18. Pulpal status of human primary teeth with physiological root resorption.

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    Monteiro, Joana; Day, Peter; Duggal, Monty; Morgan, Claire; Rodd, Helen

    2009-01-01

    The overall aim of this study was to determine whether any changes occur in the pulpal structure of human primary teeth in association with physiological root resorption. The experimental material comprised 64 sound primary molars, obtained from children requiring routine dental extractions under general anaesthesia. Pulp sections were processed for indirect immunofluorescence using combinations of: (i) protein gene product 9.5 (a general neuronal marker); (ii) leucocyte common antigen CD45 (a general immune cell marker); and (iii) Ulex europaeus I lectin (a marker of vascular endothelium). Image analysis was then used to determine the percentage area of staining for each label within both the pulp horn and mid-coronal region. Following measurement of the greatest degree of root resorption in each sample, teeth were subdivided into three groups: those with physiological resorption involving less than one-third, one-third to two-thirds, and more than two-thirds of their root length. Wide variation was evident between different tooth samples with some resorbed teeth showing marked changes in pulpal histology. Decreased innervation density, increased immune cell accumulation, and increased vascularity were evident in some teeth with advanced root resorption. Analysis of pooled data, however, did not reveal any significant differences in mean percentage area of staining for any of these variables according to the three root resorption subgroups (P > 0.05, analysis of variance on transformed data). This investigation has revealed some changes in pulpal status of human primary teeth with physiological root resorption. These were not, however, as profound as one may have anticipated. It is therefore speculated that teeth could retain the potential for sensation, healing, and repair until advanced stages of root resorption.

  19. Bilateral elevation of interleukin-6 protein and mRNA in both lumbar and cervical dorsal root ganglia following unilateral chronic compression injury of the sciatic nerve

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    2013-01-01

    Background Current research implicates interleukin (IL)-6 as a key component of the nervous-system response to injury with various effects. Methods We used unilateral chronic constriction injury (CCI) of rat sciatic nerve as a model for neuropathic pain. Immunofluorescence, ELISA, western blotting and in situ hybridization were used to investigate bilateral changes in IL-6 protein and mRNA in both lumbar (L4-L5) and cervical (C7-C8) dorsal root ganglia (DRG) following CCI. The operated (CCI) and sham-operated (sham) rats were assessed after 1, 3, 7, and 14 days. Withdrawal thresholds for mechanical hyperalgesia and latencies for thermal hyperalgesia were measured in both ipsilateral and contralateral hind and fore paws. Results The ipsilateral hind paws of all CCI rats displayed a decreased threshold of mechanical hyperalgesia and withdrawal latency of thermal hyperalgesia, while the contralateral hind and fore paws of both sides exhibited no significant changes in mechanical or thermal sensitivity. No significant behavioral changes were found in the hind and fore paws on either side of the sham rats, except for thermal hypersensitivity, which was present bilaterally at 3 days. Unilateral CCI of the sciatic nerve induced a bilateral increase in IL-6 immunostaining in the neuronal bodies and satellite glial cells (SGC) surrounding neurons of both lumbar and cervical DRG, compared with those of naive control rats. This bilateral increase in IL-6 protein levels was confirmed by ELISA and western blotting. More intense staining for IL-6 mRNA was detected in lumbar and cervical DRG from both sides of rats following CCI. The DRG removed from sham rats displayed a similar pattern of staining for IL-6 protein and mRNA as found in naive DRG, but there was a higher staining intensity in SGC. Conclusions Bilateral elevation of IL-6 protein and mRNA is not limited to DRG homonymous to the injured nerve, but also extended to DRG that are heteronymous to the injured nerve. The

  20. Electromagnetic radiation (Wi-Fi) and epilepsy induce calcium entry and apoptosis through activation of TRPV1 channel in hippocampus and dorsal root ganglion of rats.

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    Ghazizadeh, Vahid; Nazıroğlu, Mustafa

    2014-09-01

    Incidence rates of epilepsy and use of Wi-Fi worldwide have been increasing. TRPV1 is a Ca(2+) permeable and non-selective channel, gated by noxious heat, oxidative stress and capsaicin (CAP). The hyperthermia and oxidant effects of Wi-Fi may induce apoptosis and Ca(2+) entry through activation of TRPV1 channel in epilepsy. Therefore, we tested the effects of Wi-Fi (2.45 GHz) exposure on Ca(2+) influx, oxidative stress and apoptosis through TRPV1 channel in the murine dorsal root ganglion (DRG) and hippocampus of pentylentetrazol (PTZ)-induced epileptic rats. Rats in the present study were divided into two groups as controls and PTZ. The PTZ groups were divided into two subgroups namely PTZ + Wi-Fi and PTZ + Wi-Fi + capsazepine (CPZ). The hippocampal and DRG neurons were freshly isolated from the rats. The DRG and hippocampus in PTZ + Wi-Fi and PTZ + Wi-Fi + CPZ groups were exposed to Wi-Fi for 1 hour before CAP stimulation. The cytosolic free Ca(2+), reactive oxygen species production, apoptosis, mitochondrial membrane depolarization, caspase-3 and -9 values in hippocampus were higher in the PTZ group than in the control although cell viability values decreased. The Wi-Fi exposure induced additional effects on the cytosolic Ca(2+) increase. However, pretreatment of the neurons with CPZ, results in a protection against epilepsy-induced Ca(2+) influx, apoptosis and oxidative damages. In results of whole cell patch-clamp experiments, treatment of DRG with Ca(2+) channel antagonists [thapsigargin, verapamil + diltiazem, 2-APB, MK-801] indicated that Wi-Fi exposure induced Ca(2+) influx via the TRPV1 channels. In conclusion, epilepsy and Wi-Fi in our experimental model is involved in Ca(2+) influx and oxidative stress-induced hippocampal and DRG death through activation of TRPV1 channels, and negative modulation of this channel activity by CPZ pretreatment may account for the neuroprotective activity against oxidative stress.

  1. Upregulation of casein kinase 1ε in dorsal root ganglia and spinal cord after mouse spinal nerve injury contributes to neuropathic pain

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    Zong Shuqin

    2009-12-01

    Full Text Available Abstract Background Neuropathic pain is a complex chronic pain generated by damage to, or pathological changes in the somatosensory nervous system. Characteristic features of neuropathic pain are allodynia, hyperalgesia and spontaneous pain. Such abnormalities associated with neuropathic pain state remain to be a significant clinical problem. However, the neuronal mechanisms underlying the pathogenesis of neuropathic pain are complex and still poorly understood. Casein kinase 1 is a serine/threonine protein kinase and has been implicated in a wide range of signaling activities such as cell differentiation, proliferation, apoptosis, circadian rhythms and membrane transport. In mammals, the CK1 family consists of seven members (α, β, γ1, γ2, γ3, δ, and ε with a highly conserved kinase domain and divergent amino- and carboxy-termini. Results Preliminary cDNA microarray analysis revealed that the expression of the casein kinase 1 epsilon (CK1ε mRNA in the spinal cord of the neuropathic pain-resistant N- type Ca2+ channel deficient (Cav2.2-/- mice was decreased by the spinal nerve injury. The same injury exerted no effects on the expression of CK1ε mRNA in the wild-type mice. Western blot analysis of the spinal cord identified the downregulation of CK1ε protein in the injured Cav2.2-/- mice, which is consistent with the data of microarray analysis. However, the expression of CK1ε protein was found to be up-regulated in the spinal cord of injured wild-type mice. Immunocytochemical analysis revealed that the spinal nerve injury changed the expression profiles of CK1ε protein in the dorsal root ganglion (DRG and the spinal cord neurons. Both the percentage of CK1ε-positive neurons and the expression level of CK1ε protein were increased in DRG and the spinal cord of the neuropathic mice. These changes were reversed in the spinal cord of the injured Cav2.2-/- mice. Furthermore, intrathecal administration of a CK1 inhibitor IC261 produced

  2. Increased Hyperalgesia and Proinflammatory Cytokines in the Spinal Cord and Dorsal Root Ganglion After Surgery and/or Fentanyl Administration in Rats.

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    Chang, Lu; Ye, Fang; Luo, Quehua; Tao, Yuanxiang; Shu, Haihua

    2018-01-01

    Perioperative fentanyl has been reported to induce hyperalgesia and increase postoperative pain. In this study, we tried to investigate behavioral hyperalgesia, the expression of proinflammatory cytokines, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), and the activation of microglia in the spinal cord and dorsal root ganglion (DRG) in a rat model of surgical plantar incision with or without perioperative fentanyl. Four groups of rats (n = 32 for each group) were subcutaneously injected with fentanyl at 60 μg/kg or normal saline for 4 times with 15-minute intervals. Plantar incisions were made to rats in 2 groups after the second drug injection. Mechanical and thermal nociceptive thresholds were assessed by the tail pressure test and paw withdrawal test on the day before, at 1, 2, 3, 4 hours, and on the days 1-7 after drug injection. The lumbar spinal cord, bilateral DRG, and cerebrospinal fluid of 4 rats in each group were collected to measure IL-1β, IL-6, and TNF-α on the day before, at the fourth hour, and on the days 1, 3, 5, and 7 after drug injection. The lumbar spinal cord and bilateral DRG were removed to detect the ionized calcium-binding adapter molecule 1 on the day before and on the days 1 and 7 after drug injection. Rats injected with normal saline only demonstrated no significant mechanical or thermal hyperalgesia or any increases of IL-1β, IL-6, and TNF-α in the spinal cord or DRG. However, injection of fentanyl induced analgesia within as early as 4 hours and a significant delayed tail mechanical and bilateral plantar thermal hyperalgesia after injections lasting for 2 days, while surgical plantar incision induced a significant mechanical and thermal hyperalgesia lasting for 1-4 days. The combination of fentanyl and incision further aggravated the hyperalgesia and prolonged the duration of hyperalgesia. The fentanyl or surgical incision upregulated the expression of IL-1β, IL-6, and TNF-α in the

  3. Intense isolectin-B4 binding in rat dorsal root ganglion neurons distinguishes C-fiber nociceptors with broad action potentials and high Nav1.9 expression.

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    Fang, Xin; Djouhri, Laiche; McMullan, Simon; Berry, Carol; Waxman, Stephen G; Okuse, Kenji; Lawson, Sally N

    2006-07-05

    Binding to isolectin-B4 (IB4) and expression of tyrosine kinase A (trkA) (the high-affinity NGF receptor) have been used to define two different subgroups of nociceptive small dorsal root ganglion (DRG) neurons. We previously showed that only nociceptors have high trkA levels. However, information about sensory and electrophysiological properties in vivo of single identified IB4-binding neurons, and about their trkA expression levels, is lacking. IB4-positive (IB4+) and small dark neurons had similar size distributions. We examined IB4-binding levels in >120 dye-injected DRG neurons with sensory and electrophysiological properties recorded in vivo. Relative immunointensities for trkA and two TTX-resistant sodium channels (Nav1.8 and Nav1.9) were also measured in these neurons. IB4+ neurons were classified as strongly or weakly IB4+. All strongly IB4+ neurons were C-nociceptor type (C-fiber nociceptive or unresponsive). Of 32 C-nociceptor-type neurons examined, approximately 50% were strongly IB4+, approximately 20% were weakly IB4+ and approximately 30% were IB4-. Adelta low-threshold mechanoreceptive (LTM) neurons were weakly IB4+ or IB4-. All 33 A-fiber nociceptors and all 44 Aalpha/beta-LTM neurons examined were IB4-. IB4+ compared with IB4- C-nociceptor-type neurons had longer somatic action potential durations and rise times, slower conduction velocities, more negative membrane potentials, and greater immunointensities for Nav1.9 but not Nav1.8. Immunointensities of IB4 binding in C-neurons were positively correlated with those of Nav1.9 but not Nav1.8. Of 23 C-neurons tested for both trkA and IB4, approximately 35% were trkA+/IB4+ but with negatively correlated immunointensities; 26% were IB4+/trkA-, and 35% were IB4-/trkA+. We conclude that strongly IB4+ DRG neurons are exclusively C-nociceptor type and that high Nav1.9 expression may contribute to their distinct membrane properties.

  4. Effects of estrogens and bladder inflammation on mitogen-activated protein kinases in lumbosacral dorsal root ganglia from adult female rats

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    Keast Janet R

    2009-12-01

    Full Text Available Abstract Background Interstitial cystitis is a chronic condition associated with bladder inflammation and, like a number of other chronic pain states, symptoms associated with interstitial cystitis are more common in females and fluctuate during the menstrual cycle. The aim of this study was to determine if estrogens could directly modulate signalling pathways within bladder sensory neurons, such as extracellular signal-related kinase (ERK and p38 mitogen-activated protein (MAP kinases. These signalling pathways have been implicated in neuronal plasticity underlying development of inflammatory somatic pain but have not been as extensively investigated in visceral nociceptors. We have focused on lumbosacral dorsal root ganglion (DRG neurons projecting to pelvic viscera (L1, L2, L6, S1 of adult female Sprague-Dawley rats and performed both in vitro and in vivo manipulations to compare the effects of short- and long-term changes in estrogen levels on MAPK expression and activation. We have also investigated if prolonged estrogen deprivation influences the effects of lower urinary tract inflammation on MAPK signalling. Results In studies of isolated DRG neurons in short-term (overnight culture, we found that estradiol and estrogen receptor (ER agonists rapidly stimulated ER-dependent p38 phosphorylation relative to total p38. Examination of DRGs following chronic estrogen deprivation in vivo (ovariectomy showed a parallel increase in total and phosphorylated p38 (relative to β-tubulin. We also observed an increase in ERK1 phosphorylation (relative to total ERK1, but no change in ERK1 expression (relative to β-tubulin. We observed no change in ERK2 expression or phosphorylation. Although ovariectomy increased the level of phosphorylated ERK1 (vs. total ERK1, cyclophosphamide-induced lower urinary tract inflammation did not cause a net increase of either ERK1 or ERK2, or their phosphorylation. Inflammation did, however, cause an increase in p38

  5. CLASSIFICATION OF ORGANIZATIONAL FAILURE ROOT CAUSES PRODUCING HUMAN ERROR

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    S. Arghami

    2006-08-01

    Full Text Available The formal study of human error is relatively recent, especially in medical domain, and is tied closely to a several other relatively new fields. Organizational root cause of human error is less considered. Despite growing social, industrial and scientific interest in the organizational causes of incidents, the concept of organizational failure and related tools are still less considered in many developing countries e.g. Iran. Also, there is few incident record-keeping in medical domain on human error. Therefore, this study draws on case study research to investigate the applicability of a European taxonomy of organizational failure in Iran, in aviation domain with a fair incident record-keeping. This case study resulted in 10 incident in-depth descriptions, which occurred during one year in a part of civil aviation due to operator error. Within each case study, an explanation building method is used to develop a tool for classifying organizational root causes. Results include 100 root causes. The distribution of organizational root causes over the main categories of the former taxonomy shows a need to add a new sub-category to improve its applicability in Iran. The new sub-category is related to culture.

  6. Downregulation of the endogenous opioid peptides in the dorsal striatum of human alcoholics

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    Daniil eSarkisyan

    2015-05-01

    Full Text Available The endogenous opioid peptides dynorphins and enkephalins may be involved in brain-area specific synaptic adaptations relevant for different stages of an addiction cycle. We compared the levels of prodynorphin (PDYN and proenkephalin (PENK mRNAs (by qRT-PCR, and dynorphins and enkephalins (by radioimmunoassay in the caudate nucleus and putamen between alcoholics and control subjects. We also evaluated whether PDYN promoter variant rs1997794 associated with alcoholism affects PDYN expression. Postmortem specimens obtained from 24 alcoholics and 26 controls were included in final statistical analysis. PDYN mRNA and Met-enkephalin-Arg-Phe, a marker of PENK were downregulated in the caudate of alcoholics, while PDYN mRNA and Leu-enkephalin-Arg, a marker of PDYN were decreased in the putamen of alcoholics carrying high risk rs1997794 C allele. Downregulation of opioid peptides in the dorsal striatum may contribute to development of alcoholism including changes in goal directed behavior and formation of a compulsive habit in alcoholics.

  7. The tipping point: Value differences and parallel dorsal-ventral frontal circuits gating human approach-avoidance behavior.

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    Schlund, Michael W; Brewer, Adam T; Magee, Sandy K; Richman, David M; Solomon, Scott; Ludlum, MaDonna; Dymond, Simon

    2016-08-01

    Excessive avoidance and diminished approach behavior are both prominent features of anxiety, trauma and stress related disorders. Despite this, little is known about the neuronal mechanisms supporting gating of human approach-avoidance behavior. Here, we used functional magnetic resonance imaging (fMRI) to track dorsal anterior cingulate and medial prefrontal (dACC/dmPFC) activation along an approach-avoidance continuum to assess sensitivity to competing appetitive and aversive contingencies and correspondence with behavior change. Behavioral and fMRI experiments were conducted using a novel approach-avoidance task where a monetary reward appeared in the presence of a conditioned stimulus (CS), or threat, that signaled increasing probability of unconditioned stimulus (US) delivery. Approach produced the reward or probabilistic US, while avoidance prevented US delivery, and across trials, reward remained fixed while the CS threat level varied unpredictably. Increasing the CS threat level (i.e., US probability) produced the desired approach-avoidance transition and inverted U-shaped changes in decision times, electrodermal activity and activation in pregenual ACC, dACC/dmPFC, striatum, anterior insula and inferior frontal regions. Conversely, U-shaped changes in activation were observed in dorsolateral and ventromedial prefrontal cortex and bimodal changes in the orbitofrontal and ventral hippocampus. These new results show parallel dorsal-ventral frontal circuits support gating of human approach-avoidance behavior where dACC/dmPFC signals inversely correlate with value differences between approach and avoidance contingencies while ventral frontal signals correlate with the value of predictable outcomes. Our findings provide an important bridge between basic research on brain mechanisms of value-guided decision-making and value-focused clinical theories of anxiety and related interventions. Published by Elsevier Inc.

  8. [Selective cervical dorsal root cutting off part of the vertebral lateral mass fixation combined with exercise therapy for treating spastic cerebral paralysis of the upper limbs caused by cerebral palsy].

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    Zhang, Peng; Hu, Wei; Cao, Xu; Xu, Shi-gang; Li, De-kui; Xu, Lin

    2009-10-01

    To explore the feasibility and the result for the surgical treatment of spastic cerebral paralysis of the upper limbs in patients who underwent the selective cervical dorsal root cutting off part of the vertebral lateral mass fixation combined with exercise therapy. From March 2004 to April 2008, 27 patients included 19 boys and 8 girls, aging 13-21 years with an average of 15 years underwent selective cervical dorsal root cutting off part of the vertebral lateral mass fixation with exercise therapy. The AXIS 8 holes titanium plate was inserted into the lateral mass of spinous process through guidance of the nerve stimulator, choosed fasciculus of low-threshold nerve dorsal root and cut off its 1.5 cm. After two weeks, training exercise therapy was done in patients. Training will include lying position, turning body, sitting position, crawling, kneeling and standing position, walking and so on. Spastic Bobath inhibiting abnormal pattern was done in the whole process of training. The muscular tension, motor function (GMFM), functional independence (WeeFIM) were observed after treatment. All patients were followed up from 4 to 16 months with an average of 6 months. Muscular tension score were respectively 3.30 +/- 0.47 and 1.25 +/- 0.44 before and after treatment;GMFM score were respectively 107.82 +/- 55.17 and 131.28 +/- 46.45; WeeFIM score were respectively 57.61 +/- 25.51 and 87.91 +/- 22.39. There was significant improvement before and after treatment (P cerebral paralysis of the upper limbs is safe and effective method, which can decrease muscular tension and improve motor function, which deserves more wide use.

  9. Repetitive TMS Suggests a Role of the Human Dorsal Premotor Cortex in Action Prediction

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    Stadler, Waltraud; Ott, Derek V. M.; Springer, Anne; Schubotz, Ricarda I.; Schütz-Bosbach, Simone; Prinz, Wolfgang

    2012-01-01

    Predicting the actions of other individuals is crucial for our daily interactions. Recent evidence suggests that the prediction of object-directed arm and full-body actions employs the dorsal premotor cortex (PMd). Thus, the neural substrate involved in action control may also be essential for action prediction. Here, we aimed to address this issue and hypothesized that disrupting the PMd impairs action prediction. Using fMRI-guided coil navigation, rTMS (five pulses, 10 Hz) was applied over the left PMd and over the vertex (control region) while participants observed everyday actions in video clips that were transiently occluded for 1 s. The participants detected manipulations in the time course of occluded actions, which required them to internally predict the actions during occlusion. To differentiate between functional roles that the PMd could play in prediction, rTMS was either delivered at occluder-onset (TMS-early), affecting the initiation of action prediction, or 300 ms later during occlusion (TMS-late), affecting the maintenance of an ongoing prediction. TMS-early over the left PMd produced more prediction errors than TMS-early over the vertex. TMS-late had no effect on prediction performance, suggesting that the left PMd might be involved particularly during the initiation of internally guided action prediction but may play a subordinate role in maintaining ongoing prediction. These findings open a new perspective on the role of the left PMd in action prediction which is in line with its functions in action control and in cognitive tasks. In the discussion, the relevance of the left PMd for integrating external action parameters with the observer’s motor repertoire is emphasized. Overall, the results are in line with the notion that premotor functions are employed in both action control and action observation. PMID:22363279

  10. Anti-inflammatory effects of dexamethasone and meloxicam on Borrelia burgdorferi-induced inflammation in neuronal cultures of dorsal root ganglia and myelinating cells of the peripheral nervous system.

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    Ramesh, Geeta; Meisner, Olivia C; Philipp, Mario T

    2015-12-23

    Lyme neuroborreliosis (LNB), caused by the spirochete Borrelia burgdorferi (Bb), could result in cognitive impairment, motor dysfunction, and radiculoneuritis. We hypothesized that inflammation is a key factor in LNB pathogenesis and recently evaluated the effects of dexamethasone, a steroidal anti-inflammatory drug, and meloxicam a non-steroidal anti-inflammatory drug (NSAID), in a rhesus monkey model of acute LNB. Dexamethasone treatment significantly reduced the levels of immune mediators, and prevented inflammatory and/or neurodegenerative lesions in the central and peripheral nervous systems, and apoptosis in the dorsal root ganglia (DRG). However, infected animals treated with meloxicam showed levels of inflammatory mediators, inflammatory lesions, and DRG cell apoptosis that were similar to that of the infected animals that were left untreated. To address the differential anti-inflammatory effects of dexamethasone and meloxicam on neuronal and myelinating cells of the peripheral nervous system (PNS), we evaluated the potential of these drugs to alter the levels of Bb-induced inflammatory mediators in rhesus DRG cell cultures and primary human Schwann cells (HSC), using multiplex enzyme-linked immunosorbent assays (ELISA). We also ascertained the ability of these drugs to modulate cell death as induced by live Bb in HSC using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay and the potential of dexamethasone to modulate Bb-induced apoptosis in HSC by the TUNEL assay. Earlier, we reported that dexamethasone significantly reduced Bb-induced immune mediators and apoptosis in rhesus DRG cell cultures. Here, we report that dexamethasone but not meloxicam significantly reduces the levels of several cytokines and chemokines as induced by live Bb, in HSC and DRG cell cultures. Further, meloxicam does not significantly alter Bb-induced cell death in HSC, while dexamethasone protects HSC against Bb-induced cell death. These data

  11. CC chemokine ligand 2 upregulates the current density and expression of TRPV1 channels and Nav1.8 sodium channels in dorsal root ganglion neurons

    Directory of Open Access Journals (Sweden)

    Kao Der-Jang

    2012-08-01

    Full Text Available Abstract Background Inflammation or nerve injury-induced upregulation and release of chemokine CC chemokine ligand 2 (CCL2 within the dorsal root ganglion (DRG is believed to enhance the activity of DRG nociceptive neurons and cause hyperalgesia. Transient receptor potential vanilloid receptor 1 (TRPV1 and tetrodotoxin (TTX-resistant Nav1.8 sodium channels play an essential role in regulating the excitability and pain transmission of DRG nociceptive neurons. We therefore tested the hypothesis that CCL2 causes peripheral sensitization of nociceptive DRG neurons by upregulating the function and expression of TRPV1 and Nav1.8 channels. Methods DRG neuronal culture was prepared from 3-week-old Sprague–Dawley rats and incubated with various concentrations of CCL2 for 24 to 36 hours. Whole-cell voltage-clamp recordings were performed to record TRPV1 agonist capsaicin-evoked inward currents or TTX-insensitive Na+ currents from control or CCL2-treated small DRG sensory neurons. The CCL2 effect on the mRNA expression of TRPV1 or Nav1.8 was measured by real-time quantitative RT-PCR assay. Results Pretreatment of CCL2 for 24 to 36 hours dose-dependently (EC50 value = 0.6 ± 0.05 nM increased the density of capsaicin-induced currents in small putative DRG nociceptive neurons. TRPV1 mRNA expression was greatly upregulated in DRG neurons preincubated with 5 nM CCL2. Pretreating small DRG sensory neurons with CCL2 also increased the density of TTX-resistant Na+ currents with a concentration-dependent manner (EC50 value = 0.7 ± 0.06 nM. The Nav1.8 mRNA level was significantly increased in DRG neurons pretreated with CCL2. In contrast, CCL2 preincubation failed to affect the mRNA level of TTX-resistant Nav1.9. In the presence of the specific phosphatidylinositol-3 kinase (PI3K inhibitor LY294002 or Akt inhibitor IV, CCL2 pretreatment failed to increase the current density of capsaicin-evoked inward currents or TTX-insensitive Na+ currents and

  12. Prolegomena of Human Rights. Historical Roots and Globalization

    Directory of Open Access Journals (Sweden)

    Ana-Alina Dumitrache-Ionescu

    2015-05-01

    Full Text Available The paper Prolegomena of Human Rights. Historical Roots and Globalization analyses the complexity of the history of human rights which revolve around an incessant struggle for the awareness of the value of the human being. It is the history which defends the man, the human being, regarded individually or collectively, who was subjected in the course of time to some atrocities and abuses, confronting itself with exploitation, discrimination, oppression, slavery, torture and even extermination. Moreover, the historical evolution of human rights knows halting places in which the concepts of human rights are accompanied by ambiguity, by different meanings for different people and vary in accordance with the context. By way of resemblance, the problem of human rights in the context of globalization which transforms human rights into rights of the global citizen, rights which acquire new dimensions and significances imposed by the economic, politic and social changes specific of globalization is approached in this paper. The global vision of the new human rights involves both the opportunity to have a say when they are infringed for example, when they are subjected to torture or terror, and where human rights abuses are carried out by the people, for example, trafficking in human beings. (Ritzer, & Dean, 2015, p. 115

  13. The human dorsal premotor cortex facilitates the excitability of ipsilateral primary motor cortex via a short latency cortico-cortical route.

    NARCIS (Netherlands)

    Groppa, S.; Schlaak, B.H.; Munchau, A.; Werner-Petroll, N.; Dunnweber, J.; Baumer, T.; Nuenen, B.F.L. van; Siebner, H.R.

    2012-01-01

    In non-human primates, invasive tracing and electrostimulation studies have identified strong ipsilateral cortico-cortical connections between dorsal premotor- (PMd) and the primary motor cortex (M1(HAND) ). Here, we applied dual-site transcranial magnetic stimulation (dsTMS) to left PMd and

  14. Sex differences in pain-related behavior and expression of calcium/calmodulin-dependent protein kinase II in dorsal root ganglia of rats with diabetes type 1 and type 2.

    Science.gov (United States)

    Ferhatovic, Lejla; Banozic, Adriana; Kostic, Sandra; Sapunar, Damir; Puljak, Livia

    2013-06-01

    Sex differences in pain-related behavior and expression of calcium/calmodulin dependent protein kinase II (CaMKII) in dorsal root ganglia were studied in rat models of Diabetes mellitus type 1 (DM1) and type 2 (DM2). DM1 was induced with 55mg/kg streptozotocin, and DM2 with a combination of high-fat diet and 35mg/kg of streptozotocin. Pain-related behavior was analyzed using thermal and mechanical stimuli. The expression of CaMKII was analyzed with immunofluorescence. Sexual dimorphism in glycemia, and expression of CaMKII was observed in the rat model of DM1, but not in DM2 animals. Increased expression of total CaMKII (tCaMKII) in small-diameter dorsal root ganglia neurons, which are associated with nociception, was found only in male DM1 rats. None of the animals showed increased expression of the phosphorylated alpha CaMKII isoform in small-diameter neurons. The expression of gamma and delta isoforms of CaMKII remained unchanged in all analyzed animal groups. Different patterns of glycemia and tCaMKII expression in male and female model of DM1 were not associated with sexual dimorphism in pain-related behavior. The present findings do not suggest sex-related differences in diabetic painful peripheral neuropathy in male and female diabetic rats. Copyright © 2012 Elsevier GmbH. All rights reserved.

  15. Understanding the Dorsal and Ventral Systems of the Human Cerebral Cortex: Beyond Dichotomies

    Science.gov (United States)

    Borst, Gregoire; Thompson, William L.; Kosslyn, Stephen M.

    2011-01-01

    Traditionally, characterizations of the macrolevel functional organization of the human cerebral cortex have focused on the left and right cerebral hemispheres. However, the idea of left brain versus right brain functions has been shown to be an oversimplification. We argue here that a top-bottom divide, rather than a left-right divide, is a more…

  16. Population activity in the human dorsal pathway predicts the accuracy of visual motion detection.

    NARCIS (Netherlands)

    Donner, T.H.; Siegel, M.; Oostenveld, R.; Fries, P.; Bauer, M.; Engel, A.K.

    2007-01-01

    A person's ability to detect a weak visual target stimulus varies from one viewing to the next. We tested whether the trial-to-trial fluctuations of neural population activity in the human brain are related to the fluctuations of behavioral performance in a "yes-no" visual motion-detection task. We

  17. The human dorsal premotor cortex facilitates the excitability of ipsilateral primary motor cortex via a short latency cortico-cortical route

    DEFF Research Database (Denmark)

    Groppa, Sergiu; Schlaak, Boris H; Münchau, Alexander

    2012-01-01

    In non-human primates, invasive tracing and electrostimulation studies have identified strong ipsilateral cortico-cortical connections between dorsal premotor- (PMd) and the primary motor cortex (M1(HAND) ). Here, we applied dual-site transcranial magnetic stimulation (dsTMS) to left PMd and M1(H...... corticospinal volleys. This paradigm opens up new possibilities to study context-dependent intrahemispheric PMd-to-M1(HAND) interactions in the intact human brain....

  18. On a mathematical model of a human root dentin.

    Science.gov (United States)

    Petrovic, Ljubomir M; Spasic, Dragan T; Atanackovic, Teodor M

    2005-02-01

    On the basis of recent experimental data, a new mathematical model that predicts creep in human root dentin has been developed. The chosen constitutive model comprises fractional derivatives of stress and strain and the restrictions on the coefficients that follow from the Clausius-Duhem inequality. The four constants describing mechanical properties of the human dentin at constant temperature are calculated from a highly non-linear system involving Mittag-Leffler-type functions. Special attention is paid to thermodynamical restrictions that should be observed in determining parameters of the model from experimental results. The proposed model allows us to predict behavior of a human dentin in different load situations. Also it could be used for describing mechanical properties of dentin that are important in the development of 'dentin-like' restorative materials.

  19. Sorption of fibronectin to human root surfaces in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Mendieta, C.; Caravana, C.; Fine, D.H. (Columbia Univ., New York, NY (USA))

    1990-05-01

    The purpose of this study was to determine the conditions that favor the sorption and retention of human plasma fibronectin to cementum. Rectangular root segments prepared from teeth extracted for orthodontic reasons were mounted on a capillary pipette and immersed in solutions of {sup 125}I fibronectin for assay of cementum sorption under various conditions. Kinetic studies showed sorption to be rapid, with 77% of the maximum fibronectin sorption occurring within 1 minute. Fibronectin sorption was reduced when added in conjunction with serum and was inhibited by monovalent ions (such as sodium), but enhanced in the presence of divalent cations (such as calcium). Exposure of cementum to serum partially blocked subsequent sorption of fibronectin, while cementum bound fibronectin was eluted by subsequent exposure to serum. Treatment of cementum with citric acid pH 1.1 (4 minutes) followed by 5% sodium hypochlorite (5 minutes) caused a significant increase in fibronectin sorption with maximum retention upon subsequent exposure to serum (P less than 0.05). Fibronectin sorption to cementum was: rapid, electrostatic in nature, competitive, reversible, Ca+(+)-facilitated, and maximized by prior treatment of the root with citric acid and sodium hypochlorite. It is concluded that sorption of fibronectin to cementum can be achieved for clinical gain; however, conditions of application can significantly influence both accumulation and subsequent release of root sorbed material.

  20. Human primordial germ cells migrate along nerve fibers and Schwann cells from the dorsal hind gut mesentery to the gonadal ridge

    DEFF Research Database (Denmark)

    Møllgård, Kjeld; Jespersen, Åse; Lutterodt, Melissa Catherine

    2010-01-01

    The aim of this study was to investigate the spatiotemporal development of autonomic nerve fibers and primordial germ cells (PGCs) along their migratory route from the dorsal mesentery to the gonadal ridges in human embryos using immunohistochemical markers and electron microscopy. Autonomic nerve...... and their intimate contact with PGCs. PGCs expressed GAGE, MAGE-A4, OCT4 and c-Kit. Serial paraffin sections showed that most PGCs were located inside bundles of autonomic nerve fibers with the majority adjacent to the most peripheral fibers (close to Schwann cells). We also show that both nerve fibers and PGCs...... arrive at the gonadal ridge between 29 and 33 days pc. In conclusion, our data suggest that PGCs in human embryos preferentially migrate along autonomic nerve fibers from the dorsal mesentery to the developing gonad where they are delivered via a fine nerve plexus....

  1. The Dorsal Striatum and the Dynamics of the Consensus Connectomes in the Frontal Lobe of the Human Brain.

    Science.gov (United States)

    Kerepesi, Csaba; Varga, Bálint; Szalkai, Balázs; Grolmusz, Vince

    2018-02-26

    In the applications of the graph theory, it is unusual that one considers numerous, pairwise different graphs on the very same set of vertices. In the case of human braingraphs or connectomes, however, this is the standard situation: the nodes correspond to anatomically identified cerebral regions, and two vertices are connected by an edge if a diffusion MRI-based workflow identifies a fiber of axons, running between the two regions, corresponding to the two vertices. Therefore, if we examine the braingraphs of n subjects, then we have n graphs on the very same, anatomically identified vertex set. It is a natural idea to describe the k-frequently appearing edges in these graphs: the edges that are present between the same two vertices in at least k out of the n graphs. Based on the NIH-funded large Human Connectome Project's public data release, we have reported the construction of the Budapest Reference Connectome Server http://www.connectome.pitgroup.org that generates and visualizes these k-frequently appearing edges. We call the graphs of the k-frequently appearing edges "k-consensus connectomes" since an edge could be included only if it is present in at least k graphs out of n. Considering the whole human brain, we have reported a surprising property of these consensus connectomes earlier. In the present work we are focusing on the frontal lobe of the brain, and we report here a similarly surprising dynamical property of the consensus connectomes when k is gradually changed from k=n to k=1: the connections between the nodes of the frontal lobe are seemingly emanating from those nodes that were connected to sub-cortical structures of the dorsal striatum: the caudate nucleus, and the putamen. We hypothesize that this dynamic behavior copies the axonal fiber development of the frontal lobe. An animation of the phenomenon is presented at https://youtu.be/wBciB2eW6_8. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Novelty, stress, and biological roots in human market behavior.

    Science.gov (United States)

    Sarapultsev, Alexey; Sarapultsev, Petr

    2014-03-01

    Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004). From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007). An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics.

  3. Novelty, Stress, and Biological Roots in Human Market Behavior

    Directory of Open Access Journals (Sweden)

    Alexey Sarapultsev

    2014-02-01

    Full Text Available Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004. From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007. An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics.

  4. Novelty, Stress, and Biological Roots in Human Market Behavior

    Science.gov (United States)

    Sarapultsev, Alexey; Sarapultsev, Petr

    2014-01-01

    Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004). From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007). An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics. PMID:25379268

  5. Stress analysis of human tooth root using various root canal instruments.

    Science.gov (United States)

    Mayhew, J T; Eleazer, P D; Hnat, W P

    2000-09-01

    This study compared external root stresses from instrumentation by several motor-driven nickel-titanium instruments to stresses developed by hand files. Twelve curved first molar mesial roots were invested in PLM-9 photoelastic material to disclose net stress transmitted from the canal through the dentin. Minimal fringe patterns were observed during instrumentation with all techniques. Light-speed yielded the least change. In no case was a complete 60 psi fringe change noted.

  6. Human based roots of failures in nuclear events investigations

    Energy Technology Data Exchange (ETDEWEB)

    Ziedelis, Stanislovas; Noel, Marc; Strucic, Miodrag [Commission of the European Communities, Petten (Netherlands). European Clearinghouse on Operational Experience Feedback for Nuclear Power Plants

    2012-10-15

    This paper aims for improvement of quality of the event investigations in the nuclear industry through analysis of the existing practices, identifying and removing the existing Human and Organizational Factors (HOF) and management related barriers. It presents the essential results of several studies performed by the European Clearinghouse on Operational Experience. Outcomes of studies are based on survey of currently existing event investigation practices typical for nuclear industry of 12 European countries, as well as on insights from analysis of numerous event investigation reports. System of operational experience feedback from information based on event investigation results is not enough effective to prevent and even to decrease frequency of recurring events due to existing methodological, HOF-related and/or knowledge management related constraints. Besides that, several latent root causes of unsuccessful event investigation are related to weaknesses in safety culture of personnel and managers. These weaknesses include focus on costs or schedule, political manipulation, arrogance, ignorance, entitlement and/or autocracy. Upgrades in safety culture of organization's personnel and its senior management especially seem to be an effective way to improvement. Increasing of competencies, capabilities and level of independency of event investigation teams, elaboration of comprehensive software, ensuring of positive approach, adequate support and impartiality of management could also facilitate for improvement of quality of the event investigations. (orig.)

  7. Morphology of root canals in lower human premolars | Baroudi ...

    African Journals Online (AJOL)

    Background The knowledge of the root canal morphology and the possible anatomical variations of mandibular premolars are important for the successful endodontic treatment of such cases. The aim of this study was to investigate the presence of two or three root canals in extracted first and second mandibular premolars ...

  8. Dorsal Pancreatic Agenesis

    OpenAIRE

    Oya Uygur-Bayramiçli; Can Dolapçioglu; Derya Öztas; Resat Dabak; Gamze Kiliçoglu

    2007-01-01

    Context Agenesis of the dorsal pancreas is a rare entity and might present with various symptoms. We report a case which presented with chronic pancreatitis. Case report The patient presented with epigastric pain and we found dorsal pancreatic agenesis causing chronic pancreatitis. Conclusions Dorsal pancreatic agenesis can be easily diagnosed with new techniques and its association with clinical syndromes can be better understood.

  9. Bay11-7082 attenuates neuropathic pain via inhibition of nuclear factor-kappa B and nucleotide-binding domain-like receptor protein 3 inflammasome activation in dorsal root ganglions in a rat model of lumbar disc herniation

    Directory of Open Access Journals (Sweden)

    Zhang AL

    2017-02-01

    Full Text Available Ailiang Zhang, Kun Wang, Lianghua Ding, Xinnan Bao, Xuan Wang, Xubin Qiu, Jinbo Liu Spine Surgery, Third Affiliated Hospital of Soochow University, Changzhou, People’s Republic of China Abstract: Lumbar disc herniation (LDH is an important cause of radiculopathy, but the underlying mechanisms are incompletely understood. Many studies suggested that local inflammation, rather than mechanical compression, results in radiculopathy induced by LDH. On the molecular and cellular level, nuclear factor-kappa B (NF-κB and nucleotide-binding domain-like receptor protein 3 (NLRP3 inflammasome have been implicated in the regulation of neuroinflammation formation and progression. In this study, the autologous nucleus pulposus (NP was implanted in the left L5 dorsal root ganglion (DRG to mimic LDH in rats. We investigated the expression of NF-κB and the components of NLRP3 inflammasome in the DRG neurons in rats. Western blotting and immunofluorescence for the related molecules, including NLRP3, apoptosis-associated speck-like protein containing caspase-1 activator domain (ASC, caspase-1, interleukin (IL-1β, IL-18, IκBα, p-IκBα, p65, p-p65, and calcitonin gene-related peptide (CGRP were examined. In the NP-treated group, the activations of NLRP3, ASC, caspase-1, IL-1β, IL-18, p-IκBα, and p-p65 in DRG neurons in rats were elevated at 1 day after surgery, and the peak occurred at 7 days. Treatment with Bay11-7082, an inhibitor of the actions of IKK-β, was able to inhibit expression and activation of the molecules (NLRP3, ASC, caspase-1, IL-1β, IL-18, p-IκBα, and p-p65 and relieve the pain in rats. Our study shows that NF-κB and NLRP3 inflammasome are involved in the maintenance of NP-induced pain, and that Bay11-7082 could alleviate mechanical allodynia and thermal hyperalgesia by inhibiting NF-κB and NLRP3 inflammasome activation. Keywords: pain, NLRP3, NF-κB, dorsal root ganglion, nucleus pulposus

  10. Expression of the sodium channel transcripts Na(v)1.8 and Na(v)1.9 in injured dorsal root ganglion neurons of interferon-gamma or interferon-gamma receptor deficient mice.

    Science.gov (United States)

    Eriksson, Jonas; Fried, Kaj

    2003-03-06

    Changes in the dorsal root ganglion (DRG) expression of the sodium channels Na(v)1.8 and Na(v)1.9 may contribute to injury-induced hyperexcitability and pain. Interferon (IFN)-gamma receptor -/- mice display a reduced pain-related behavior after nerve injury as compared to wild-type mice (NeuroReport 8 (1997) 1311). To elucidate a possible role for IFN-gamma in the regulation of sodium channels, we have studied the DRG mRNA expression of Na(v)1.8/Na(v)1.9 in IFN-gamma- or IFN-gamma receptor-deficient mice. In both types of mice, nerve damage induced a downregulation of Na(v)1.8 as well as Na(v)1.9. The magnitude of this reduction was similar to that observed in wild-type animals. These results indicate that the downregulation of Na(v)1.8/Na(v)1.9 in damaged DRG neurons is not influenced by IFN-gamma. Thus, the reduced pain-related behavior of nerve-injured IFN-gamma receptor null mice is not due to differential changes in the regulation of Na(v)1.8/Na(v)1.9 mRNA.

  11. Electroacupuncture Reduces Carrageenan- and CFA-Induced Inflammatory Pain Accompanied by Changing the Expression of Nav1.7 and Nav1.8, rather than Nav1.9, in Mice Dorsal Root Ganglia

    Directory of Open Access Journals (Sweden)

    Chun-Ping Huang

    2013-01-01

    Full Text Available Several voltage-gated sodium channels (Navs from nociceptive nerve fibers have been identified as important effectors in pain signaling. The objective of this study is to investigate the electroacupuncture (EA analgesia mechanism by changing the expression of Navs in mice dorsal root ganglia (DRG. We injected carrageenan and complete Freund's adjuvant (CFA into the mice plantar surface of the hind paw to induce inflammation and examined the antinociception effect of EA at the Zusanli (ST36 acupoint at 2 Hz low frequency. Mechanical hyperalgesia was evaluated by using electronic von Frey filaments, and thermal hyperalgesia was assessed using Hargreaves' test. Furthermore, we observed the expression and quality of Navs in DRG neurons. Our results showed that EA reduced mechanical and thermal pain in inflammatory animal model. The expression of Nav1.7 and Nav1.8 was increased after 4 days of carrageenan- and CFA-elicited inflammatory pain and further attenuated by 2 Hz EA stimulation. The attenuation cannot be observed in Nav1.9 sodium channels. We demonstrated that EA at Zusanli (ST36 acupoint at 2 Hz low-frequency stimulation attenuated inflammatory pain accompanied by decreasing the expression of Nav1.7 and 1.8, rather than Nav1.9, sodium channels in peripheral DRG neurons.

  12. Acid activation of Trpv1 leads to an up-regulation of calcitonin gene-related peptide expression in dorsal root ganglion neurons via the CaMK-CREB cascade: a potential mechanism of inflammatory pain.

    Science.gov (United States)

    Nakanishi, Masako; Hata, Kenji; Nagayama, Tomotaka; Sakurai, Teruhisa; Nishisho, Toshihiko; Wakabayashi, Hiroki; Hiraga, Toru; Ebisu, Shigeyuki; Yoneda, Toshiyuki

    2010-08-01

    Increased production of calcitonin gene-related peptide (CGRP) in sensory neurons is implicated in inflammatory pain. The inflammatory site is acidic due to proton release from infiltrating inflammatory cells. Acid activation of peripheral nociceptors relays pain signals to the CNS. Here, we examined whether acid activated the transient receptor potential vanilloid subtype 1 (Trpv1), a widely recognized acid-sensing nociceptor and subsequently increased CGRP expression. Chemically induced inflammation was associated with thermal hyperalgesia and increased CGRP expression in dorsal root ganglion (DRG) in rats. In organ cultures of DRG, acid (pH 5.5) elevated CGRP expression and the selective Trpv1 antagonist 5'-Iodoresiniferatoxin decreased it. Trpv1-deficient DRG showed reduced CGRP increase by acid. Of note, many of CGRP/Trpv1-positive DRG neurons exhibited the phosphorylation of cAMP response element-binding protein (CREB), a nociceptive transcription factor. Knockdown of CREB by small interfering RNA or a dominant-negative form of CREB diminished acid-elevated CGRP expression. Acid elevated the transcriptional activity of CREB, which in turn stimulated CGRP gene promoter activity. These effects were inhibited by a Ca(2+)/calmodulin-dependent protein kinase (CaMK) inhibitor KN-93. In conclusion, our results suggest that inflammatory acidic environments activate Trpv1, leading to an up-regulation of CGRP expression via CaMK-CREB cascade, a series of events that may be associated with inflammatory pain.

  13. Electroacupuncture Reduces Carrageenan- and CFA-Induced Inflammatory Pain Accompanied by Changing the Expression of Nav1.7 and Nav1.8, rather than Nav1.9, in Mice Dorsal Root Ganglia.

    Science.gov (United States)

    Huang, Chun-Ping; Chen, Hsiang-Ni; Su, Hong-Lin; Hsieh, Ching-Liang; Chen, Wei-Hsin; Lai, Zhen-Rung; Lin, Yi-Wen

    2013-01-01

    Several voltage-gated sodium channels (Navs) from nociceptive nerve fibers have been identified as important effectors in pain signaling. The objective of this study is to investigate the electroacupuncture (EA) analgesia mechanism by changing the expression of Navs in mice dorsal root ganglia (DRG). We injected carrageenan and complete Freund's adjuvant (CFA) into the mice plantar surface of the hind paw to induce inflammation and examined the antinociception effect of EA at the Zusanli (ST36) acupoint at 2 Hz low frequency. Mechanical hyperalgesia was evaluated by using electronic von Frey filaments, and thermal hyperalgesia was assessed using Hargreaves' test. Furthermore, we observed the expression and quality of Navs in DRG neurons. Our results showed that EA reduced mechanical and thermal pain in inflammatory animal model. The expression of Nav1.7 and Nav1.8 was increased after 4 days of carrageenan- and CFA-elicited inflammatory pain and further attenuated by 2 Hz EA stimulation. The attenuation cannot be observed in Nav1.9 sodium channels. We demonstrated that EA at Zusanli (ST36) acupoint at 2 Hz low-frequency stimulation attenuated inflammatory pain accompanied by decreasing the expression of Nav1.7 and 1.8, rather than Nav1.9, sodium channels in peripheral DRG neurons.

  14. Increased expression of tetrodotoxin-resistant sodium channels Nav1.8 and Nav1.9 within dorsal root ganglia in a rat model of bone cancer pain.

    Science.gov (United States)

    Qiu, Fang; Jiang, Yuge; Zhang, Hong; Liu, Yanhong; Mi, Weidong

    2012-03-23

    In attempt to understand the underlying mechanisms of cancer-induced bone pain, we investigated the presence of two tetrodotoxin-resistant sodium channels, Nav1.8 (SNS/PN3) and Nav1.9 (SNS2/NaN), in dorsal root ganglia (DRG) neurons in an animal model of bone cancer pain. Thirty-six female Sprague-Dawley rats were randomized into three groups: Sham operation group (Sham), cancer-bearing animals killed after 7 days (C7) and cancer-bearing animals killed after 14 days group (C14). After establishment of bone cancer pain model, behavioral tests were carried out to determine the paw withdrawal threshold (PWT) of mechanical and thermal hyperalgesia, respectively. Real-time RT-PCR, Western bolt and Immunofluorescence were used to determine the mRNA and protein expression of Nav1.8 and Nav1.9 in ipsilateral lumbar 4-5 DRG. Compared to Sham group, PWT of mechanical and thermal hyperalgesia in C14 group displayed a significant decrease (PNav1.9 exhibited a significant up-regulation in C14 group (8.9 times and 9 times, respectively, PNav1.9 (PNav1.9 suggested their potential involvement in the development and maintenance of bone cancer pain. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. In vitro performance of DIAGNOdent laser fluorescence device for dental calculus detection on human tooth root surfaces

    Directory of Open Access Journals (Sweden)

    Thomas E. Rams

    2017-10-01

    Conclusions: Excellent intra- and inter-examiner reproducibility of autofluorescence intensity measurements was obtained with the DIAGNOdent laser fluorescence device on human tooth roots. Calculus-positive root surfaces exhibited significantly greater DIAGNOdent laser autofluorescence than calculus-free tooth roots, even with the laser probe tip directed parallel to root surfaces. These findings provide further in vitro validation of the potential utility of a DIAGNOdent laser fluorescence device for identifying dental calculus on human tooth root surfaces.

  16. Failure of root development of human permanent teeth following irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Yasunori; Kuroda, Masafumi; Amari, Eiichi; Yanagisawa, Toru

    1987-01-01

    Complete absence of root formation of the upper incisors, canine and first premolar was reported in a 27-year-old female who had received radiation therapy for a retinal glioma of the right eye at age of 3 years 1 month. Ground and decalcified sections showed no remarkable changes in enamel and dentin of the crowns, but the pulp floor was closed by irregular dentin deposit despite the absence of root formation. The outer surface of the irregular dentin was covered by acellular cementum, and the periodontal membrane was undeveloped. A slight degree of fibrosis was seen in the pulp, but the coronal part of the dentin was lined by odontoblasts. The theory that tooth eruption is caused by the growth of the root is not substantiated by the observation in this case.

  17. Comparison of resin push-out strength to root dentin of bovine- and human-teeth

    Directory of Open Access Journals (Sweden)

    Galhano Graziela

    2009-01-01

    Full Text Available Aim : To compare the push-out strength of bovine- and human-root dentin and, thus, evaluate the suitability of bovine-root dentin to substitute human-root dentin for bond strength testing. Materials and Methods : Ten single-rooted human-teeth and ten bovine incisors were prepared using a #3 bur of a fiber post system (12 mm long. The posts were duplicated with resin cement (Duolink. The root canals were treated with All Bond 2 adhesive system and the resin posts were cemented using Duolink. The specimens were cut perpendicular to their long axis, yielding disc-specimens with 1.5 mm thickness, which were submitted to a push-out test (1 mm/min. Ten bond strength values per group (n = 10 were used for statistical analysis (Student t test, a =.05. Results : Statistically significant differences were found for the bond strength values between bovine- (4.1 ± 1.3 MPa and human-root dentin (8.6 ± 5.7 MPa (P =.0001. Conclusion : The push-out strengths of bovine- and human-root dentin were statistically different.

  18. Upregulation of the sodium channel NaVβ4 subunit and its contributions to mechanical hypersensitivity and neuronal hyperexcitability in a rat model of radicular pain induced by local dorsal root ganglion inflammation.

    Science.gov (United States)

    Xie, Wenrui; Tan, Zhi-Yong; Barbosa, Cindy; Strong, Judith A; Cummins, Theodore R; Zhang, Jun-Ming

    2016-04-01

    High-frequency spontaneous firing in myelinated sensory neurons plays a key role in initiating pain behaviors in several different models, including the radicular pain model in which the rat lumbar dorsal root ganglia (DRG) are locally inflamed. The sodium channel isoform NaV1.6 contributes to pain behaviors and spontaneous activity in this model. Among all isoforms in adult DRG, NaV1.6 is the main carrier of tetrodotoxin-sensitive resurgent Na currents that allow high-frequency firing. Resurgent currents flow after a depolarization or action potential, as a blocking particle exits the pore. In most neurons, the regulatory β4 subunit is potentially the endogenous blocker. We used in vivo siRNA-mediated knockdown of NaVβ4 to examine its role in the DRG inflammation model. NaVβ4 but not control siRNA almost completely blocked mechanical hypersensitivity induced by DRG inflammation. Microelectrode recordings in isolated whole DRG showed that NaVβ4 siRNA blocked the inflammation-induced increase in spontaneous activity of Aβ neurons and reduced repetitive firing and other measures of excitability. NaVβ4 was preferentially expressed in larger diameter cells; DRG inflammation increased its expression, and this was reversed by NaVβ4 siRNA, based on immunohistochemistry and Western blotting. NaVβ4 siRNA also reduced immunohistochemical NaV1.6 expression. Patch-clamp recordings of tetrodotoxin-sensitive Na currents in acutely cultured medium diameter DRG neurons showed that DRG inflammation increased transient and especially resurgent current, effects blocked by NaVβ4 siRNA. NaVβ4 may represent a more specific target for pain conditions that depend on myelinated neurons expressing NaV1.6.

  19. Differential effect of D623N variant and wild-type Na(v)1.7 sodium channels on resting potential and interspike membrane potential of dorsal root ganglion neurons.

    Science.gov (United States)

    Ahn, Hye-Sook; Vasylyev, Dmytro V; Estacion, Mark; Macala, Lawrence J; Shah, Palak; Faber, Catharina G; Merkies, Ingemar S J; Dib-Hajj, Sulayman D; Waxman, Stephen G

    2013-09-05

    Sodium channel NaV1.7 is preferentially expressed in dorsal root ganglion (DRG) and sympathetic ganglion neurons. Gain-of-function NaV1.7 mutations/variants have been identified in the painful disorders inherited erythromelalgia and small-fiber neuropathy (SFN). DRG neurons transfected with these channel variants display depolarized resting potential, reduced current-threshold, increased firing-frequency and spontaneous firing. Whether the depolarizing shift in resting potential and enhanced spontaneous firing are due to persistent activity of variant channels, or to compensatory changes in other conductance(s) in response to expression of the variant channel, as shown in model systems, has not been studied. We examined the effect of wild-type NaV1.7 and a NaV1.7 mutant channel, D623N, associated with SFN, on resting potential and membrane potential during interspike intervals in DRG neurons. Resting potential in DRG neurons expressing D623N was depolarized compared to neurons expressing WT-NaV1.7. Exposure to TTX hyperpolarized resting potential by 7mV, increased current-threshold, decreased firing-frequency, and reduced NMDG-induced-hyperpolarization in DRG neurons expressing D623N. To assess the contribution of depolarized resting potential to DRG neuron excitability, we mimicked the mutant channel's depolarizing effect by current injection to produce equivalent depolarization; the depolarization decreased current threshold and increased firing-frequency. Voltage-clamp using ramp or repetitive action potentials as commands showed that D623N channels enhance the TTX-sensitive inward current, persistent at subthreshold membrane voltages, as predicted by a Hodgkin-Huxley model. Our results demonstrate that a variant of NaV1.7 associated with painful neuropathy depolarizes resting membrane potential and produces an enhanced inward current during interspike intervals, thereby contributing to DRG neuron hyperexcitability. Copyright © 2013 Elsevier B.V. All rights

  20. Stromal Cell-Derived Factor 1 Increases Tetrodotoxin-Resistant Sodium Currents Nav1.8 and Nav1.9 in Rat Dorsal Root Ganglion Neurons via Different Mechanisms.

    Science.gov (United States)

    Qiu, Fang; Li, Yang; Fu, Qiang; Fan, Yong-Yan; Zhu, Chao; Liu, Yan-Hong; Mi, Wei-Dong

    2016-07-01

    Stromal cell-derived factor 1 (SDF-1)/chemokine CXC motif ligand 12 (CXCL12), a chemokine that is upregulated in dorsal root ganglion (DRG) during chronic pain models, has recently been found to play a central role in pain hypersensitivity. The purpose of present study is to investigate the functional impact of SDF-1 and its receptor, chemokine CXC motif receptor 4 (CXCR4), on two TTXR sodium channels in rat DRG using electrophysiological techniques. Preincubation with SDF-1 caused a concentration-dependent increase of Nav1.8 and Nav1.9 currents amplitudes in acutely isolated small diameter DRG neurons in short-term culture. As to Nav1.9, changes in current density and kinetic properties of Nav1.9 current evoked by SDF-1(50 ng/ml) was eliminated by CXCR4 antagonist AMD3100 and phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. The increase in Nav1.9 current was also blocked by pertussis toxin (PTX) but not cholera toxin (CTX), showing involvement of Gi/o but not Gs subunits. As to Nav1.8, inhibitors (AMD3100, PTX, CTX, LY294002) used in present study didn't inhibit the increased amplitude of Nav1.8 current and shifted activation curve of Nav1.8 in a hyperpolarizing direction in the presence of SDF-1 (50 ng/ml). In conclusion, our data demonstrated that SDF-1 may excite primary nociceptive sensory neurons by acting on the biophysical properties of Nav1.8 and Nav1.9 currents but via different mechanisms.

  1. Inhibition of the TRPM2 and TRPV1 Channels through Hypericum perforatum in Sciatic Nerve Injury-induced Rats Demonstrates their Key Role in Apoptosis and Mitochondrial Oxidative Stress of Sciatic Nerve and Dorsal Root Ganglion

    Directory of Open Access Journals (Sweden)

    Fuat Uslusoy

    2017-05-01

    Full Text Available Sciatic nerve injury (SNI results in neuropathic pain, which is characterized by the excessive Ca2+ entry, reactive oxygen species (ROS and apoptosis processes although involvement of antioxidant Hypericum perforatum (HP through TRPM2 and TRPV1 activation has not been clarified on the processes in SNI-induced rat, yet. We investigated the protective property of HP on the processes in the sciatic nerve and dorsal root ganglion neuron (DRGN of SNI-induced rats. The rats were divided into five groups as control, sham, sham+HP, SNI, and SNI+HP. The HP groups received 30 mg/kg HP for 4 weeks after SNI induction. TRPM2 and TRPV1 channels were activated in the neurons by ADP-ribose or cumene peroxide and capsaicin, respectively. The SNI-induced TRPM2 and TRPV1 currents and intracellular free Ca2+ and ROS concentrations were reduced by HP, N-(p-amylcinnamoyl anthranilic acid (ACA, and capsazepine (CapZ. SNI-induced increase in apoptosis and mitochondrial depolarization in sciatic nerve and DRGN of SNI group were decreased by HP, ACA, and CapZ treatments. PARP-1, caspase 3 and 9 expressions in the sciatic nerve, DRGN, skin, and musculus piriformis of SNI group were also attenuated by HP treatment. In conclusion, increase of mitochondrial ROS, apoptosis, and Ca2+ entry through inhibition of TRPM2 and TRPV1 in the sciatic nerve and DRGN neurons were decreased by HP treatment. The results may be relevant to the etiology and treatment of SNI by HP.

  2. Study of root canal accessibility in human primary molars.

    Science.gov (United States)

    Aminabadi, Naser A; Farahani, Ramin M Z; Gajan, Esrafil B

    2008-03-01

    The aim of the present study was to provide a general scheme for pulpectomy of primary molars that may be useful for decision-making about negotiation of root canals and selection of appropriate instruments. A total of 160 vital primary molars in 85 patients (40 males, 45 females) aged 4-6 years were selected. After taking primary radiographs, local anesthesia was induced, and the teeth were isolated using a rubber dam. Canal accessibility index (CAI) and tooth accessibility index (TAI) were calculated according to initial file size. Mandibular first molars had either three canals (79.2%) or four canals (20.8%), and all second molars had four canals. Maxillary first molars had three canals and second molars had either three canals (70.9%) or four canals (29.1%). Lower accessibility of the mandibular first molar distobuccal root accounted for the lower accessibility of these teeth in comparison with mandibular second molars. While three-canal maxillary second molars were more accessible due to the lower accessibility of the distobuccal canal of the maxillary first molar, poor accessibility of the distal canal in four-canal second molars was responsible for the difficult accessibility of these teeth. In conclusion, it seems that the accessibility of a single canal in each tooth determines the difficulty of accessibility for any given tooth. Moreover, while primary second molars are more accessible than first molars, all of them are negotiable.

  3. Different impressions of other agents obtained through social interaction uniquely modulate dorsal and ventral pathway activities in the social human brain.

    Science.gov (United States)

    Takahashi, Hideyuki; Terada, Kazunori; Morita, Tomoyo; Suzuki, Shinsuke; Haji, Tomoki; Kozima, Hideki; Yoshikawa, Masahiro; Matsumoto, Yoshio; Omori, Takashi; Asada, Minoru; Naito, Eiichi

    2014-09-01

    Internal (neuronal) representations in the brain are modified by our experiences, and this phenomenon is not unique to sensory and motor systems. Here, we show that different impressions obtained through social interaction with a variety of agents uniquely modulate activity of dorsal and ventral pathways of the brain network that mediates human social behavior. We scanned brain activity with functional magnetic resonance imaging (fMRI) in 16 healthy volunteers when they performed a simple matching-pennies game with a human, human-like android, mechanical robot, interactive robot, and a computer. Before playing this game in the scanner, participants experienced social interactions with each opponent separately and scored their initial impressions using two questionnaires. We found that the participants perceived opponents in two mental dimensions: one represented "mind-holderness" in which participants attributed anthropomorphic impressions to some of the opponents that had mental functions, while the other dimension represented "mind-readerness" in which participants characterized opponents as intelligent. Interestingly, this "mind-readerness" dimension correlated to participants frequently changing their game tactic to prevent opponents from envisioning their strategy, and this was corroborated by increased entropy during the game. We also found that the two factors separately modulated activity in distinct social brain regions. Specifically, mind-holderness modulated activity in the dorsal aspect of the temporoparietal junction (TPJ) and medial prefrontal and posterior paracingulate cortices, while mind-readerness modulated activity in the ventral aspect of TPJ and the temporal pole. These results clearly demonstrate that activity in social brain networks is modulated through pre-scanning experiences of social interaction with a variety of agents. Furthermore, our findings elucidated the existence of two distinct functional networks in the social human brain

  4. Available chlorine consumption from NaOCl solutions passively placed in instrumented human root canals.

    Science.gov (United States)

    Ragnarsson, K T; Rechenberg, D K; Attin, T; Zehnder, M

    2015-05-01

    To monitor chlorine consumption from nonagitated aqueous sodium hypochlorite (NaOCl) solutions in human root canals using a recently developed assay, which can determine the order of magnitude of available chlorine in small volumes of liquid. The root canals of 80 extracted single-rooted human teeth were instrumented to ProTaper Universal F4 and irrigated using 1% NaOCl. Subsequently, canals were irrigated with copious amounts of deionized water to rinse out the residual chlorine. Subsequently, the teeth were sealed externally and placed in a water bath of 37 °C. Root canals were filled with NaOCl of 1%, 2.75%, 5.5%, or distilled water for 1, 10, 100 or 1000 min (n = 5 teeth per solution and time). Consumption of chlorine was measured using paper points pre-impregnated with 15% potassium iodide. Colour change of the paper points was determined photo-electronically, assessing their red value after absorbing solutions from root canals. Measurements were compared to a standard series of NaOCl down to 0.001% (n = 5 paper points per concentration). Red values of the paper points inserted into the root canal were affected by initial NaOCl concentration and time (two-way anova, P < 0.05). If NaOCl concentrations above 0.1% are considered to be clinically relevant, then 5.5% NaOCl retained its activity in the root canal for more than 100 min, whereas 1% NaOCl lost its activity between 10 and 100 min. Nonagitated NaOCl solutions can remain biologically active in human root canals for extended time periods. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  5. Right dorsal colitis

    National Research Council Canada - National Science Library

    Karcher, L F; Dill, S G; Anderson, W I; King, J M

    1990-01-01

    Moderate to severe ulcerative colitis of the right dorsal colon was diagnosed by necropsy or by exploratory celiotomy and biopsy in 13 horses with a primary clinical complaint of either colic, diarrhea, or weight loss...

  6. A quantitative analysis of mineral loss and shrinkage of in vitro demineralized human root surfaces.

    Science.gov (United States)

    Ten Cate, J M; Nyvad, B; Van de Plassche-Simons, Y M; Fejerskov, O

    1991-10-01

    Demineralization of dentin specimens proceeds at a faster rate than that of enamel. Although this is generally accepted, a quantification of the rate of formation of root lesions is hampered by the shrinkage of the lesions when these are dried prior to microradiographic analysis. This leads to a significant underestimation of the lesion depth and total mineral loss. The aim of this paper was to quantitate the rate of mineral loss during root lesion formation in vitro and to determine the shrinkage of root specimens as a result of drying. Unerupted roots of human teeth were subjected to a demineralizing system of 0.1 mol/L lactate buffer (pH = 4.8) with 0.2 mmol/L methanehydroxydiphosphonate during four, 11, 22, and 44 days. The root lesions were assessed by quantitative microradiography. The demineralizing solutions were analyzed to determine the amounts of root tissue dissolved. A comparison of these two sets of data showed that, with the demineralizing system used, root lesions may shrink up to 62%. Fixation of the specimens in fixative did not affect this shrinkage. Chemical analysis showed that mineral loss proceeded linearly with time. From the data-sets of this study, a model was developed to compensate for the shrinkage in the dentin specimens. In this way, it was possible to calculate the lesion depth at four demineralization times as being 130, 220, 320, and 530 microns, respectively. These values were in agreement with a microscopic determination of the lesion depth.

  7. Stereological analysis of Ca(2+)/calmodulin-dependent protein kinase II alpha -containing dorsal root ganglion neurons in the rat: colocalization with isolectin Griffonia simplicifolia, calcitonin gene-related peptide, or vanilloid receptor 1.

    Science.gov (United States)

    Carlton, Susan M; Hargett, Gregory L

    2002-06-17

    The enzyme Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) is widely distributed in the nervous system. A previous report describes immunostaining for CaMKII alpha in dorsal root ganglion (DRG) neurons. In this study, CaMKII alpha is colocalized in the rat with three putative markers of nociceptive DRG neurons, isolectin Griffonia simplicifolia (I-B4), identifying small-diameter, "peptide-poor" neurons; calcitonin gene-related peptide (CGRP), identifying " peptide-rich" neurons; or the vanilloid receptor 1 (VR1), identifying neurons activated by heat, acid, and capsaicin. Lumbar 4 and 5 DRG sections were labeled using immunofluorescence or lectin binding histochemistry, and percentages of single and double-labeled CaMKIIalpha neurons were determined. Stereological estimates of total neuron number in the L4 DRG were 13,815 +/- 2,798 and in the L5 DRG were 14,111 +/- 4,043. Percentages of single-labeled L4 DRG neurons were 41% +/- 2% CaMKII alpha, 38% +/- 3% I-B4, 44% +/- 3% CGRP, and 32% +/- 6% VR1. Percentages of single-labeled L5 DRG neurons were 44% +/- 5% CaMKII alpha, 48% +/- 2% I-B4, 41% +/- 7% CGRP, and 39% +/- 14% VR1. For L4 and L5, respectively, estimates of double-labeled CaMKII alpha neurons showed 34% +/- 2% and 38% +/- 17% labeled for I-B4, 25% +/- 14% and 19% +/- 10% labeled for CGRP, and 37% +/- 7% and 38% +/- 5% labeled for VR1. Conversely, for L4 and L5, respectively, 39% +/- 14% and 38% +/- 7% I-B4 binding neurons, 24% +/- 12% and 23% +/- 10% CGRP neurons, and 42% +/- 7% and 35% +/- 7% VR1 neurons labeled for CaMKIIalpha. The mean diameter of CaMKII alpha - labeled neurons was approximately 27 microm, confirming that this enzyme was preferentially localized in small DRG neurons. The results indicate that subpopulations of DRG neurons containing CaMKII alpha are likely to be involved in the processing of nociceptive information. Thus, this enzyme may play a critical role in the modulation of nociceptor activity and plasticity of primary

  8. Electron probe study of human and red deer cementum and root dentin

    Energy Technology Data Exchange (ETDEWEB)

    Toetdal, B. (Department of Physics, University of Trondheim, The Norwegian Institute of Technology); Hals, E. (Department of Cariology and Endodontics, Faculty of Odontology, University of Bergen, Norway)

    1985-01-01

    A topographical description of the concentration profiles of Ca, P, Mg, Zn, F, S, and K in human and red deer cementum and root dentin is given. The concentrations reported should be regarded as semiquantitative values. A downward slope of the Ca, P, and Mg profiles toward the pulpal cavity seemed largely to correspond with the secondary dentin. Marked elevations of the Zn profiles, modest elevations of the F profiles, and in a few instances of the S profiles, toward root surface and pulpal cavity were registered. In a couple of scans a slight elevation of the K profile toward the root surface was observed. A high degree of concordance in human and red deer teeth was ascertained.

  9. BACTERICIDAL EFFECTS OF VARIOUS IRRIGATION SOLUTIONS AGAINST STAPHYLOCOCCUS AUREUS IN HUMAN ROOT CANAL

    Directory of Open Access Journals (Sweden)

    Recai Zan

    2015-01-01

    Full Text Available Purpose: The aim of the present study was to evaluate and to compare the antibacterial effects of various irrigation solutions against Staphylococcus aureus (S. aureus in human root canals. Materials and Methods: 120 single-root mandibular premolar teeth were selected. The teeth were prepared and sterilized. S. aureus was incubated in the root canals and kept at 37°C for 24h. The infected root canals were divided into one positive (saline and one negative (sodium hypochlorite control, and four experimental groups [Ethylene-diaminetetra-aceticacid, Chlorhexidine Gluconate, Super-oxidized water(SPO, Aqueous ozone] (n=20. Flow rate of irrigation was applied with 5 mL/min flow rate for 3 min to ensure standardization among all study groups. Following the irrigation, paper points were placed in the root canals and then transferred in sterile eppendorf. Remaining bacteria were counted on blood agar plates and the data were analyzed using one-way ANOVA and Tukey’s test. Results: Although there were statistically significant differences among SPO and other experimental groups (p0.05. Conclusion: Super-oxidized water may be recommended as an alternative irrigation solution instead of NaOCl against S. aureus in root canals.

  10. Effect of chloroform, eucalyptol and orange oil solvents on the microhardness of human root dentin.

    Directory of Open Access Journals (Sweden)

    Sedigheh Khedmat

    2015-02-01

    Full Text Available This study aimed to assess the effect of chloroform, eucalyptol and orange oil solvents on the microhardness of human root dentin.Sixty-eight single-rooted single-canal extracted human premolar teeth were used. Tooth crowns were separated from the roots at the cementoenamel junction (CEJ. Roots were buccolingually sectioned into mesial and distal halves. Specimens were randomly divided into 5 groups, with 20 teeth in each solvent group and 4 teeth in each control group. Primary microhardness of specimens was measured using Vickers microhardness tester. Specimens were exposed to solvents for 15 minutes and were subjected to microhardness testing again. Data were recorded and analyzed using repeated measure ANOVA.No significant difference was found in dentin microhardness before and after exposure to solvents in any of the orange oil, eucalyptol, chloroform or saline groups (P=0.727. None of the experimental groups showed any significant difference in terms of dentin microhardness reduction (P=0.99 and had no significant difference with the negative control group.This study showed that chloroform, eucalyptol and orange oil as gutta percha solvents did not decrease the microhardness of root dentin. Thus, none of the mentioned solvents has any superiority over the others in terms of affecting dentin properties.

  11. Antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in infected human root canals.

    Science.gov (United States)

    Estrela, C; Estrela, C R A; Decurcio, D A; Hollanda, A C B; Silva, J A

    2007-02-01

    To determine the antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in human root canals infected by Enterococcus faecalis. Thirty human maxillary anterior teeth were prepared and inoculated with E. faecalis for 60 days. Eppendorf tubes were connected to the coronal portion of the teeth. Urethane hoses were attached to the tubes and to the entrance of a peristaltic pump. The exit of the apparatus corresponded to the apical portion of the root canals. The test irrigating solutions were ozonated water, gaseous ozone, 2.5% sodium hypochlorite (NaOCl), 2% chlorhexidine that circulated at a constant flow of 50 mL min(-1) for 20 min. Samples from the root canals were collected and immersed in 7 mL Letheen Broth (LB), followed by incubation at 37 degrees C for 48 h. Bacterial growth was analysed by turbidity of the culture medium and subculture on a specific nutrient broth. A 0.1 mL inoculum obtained from LB was transferred to 7 mL of brain heart infusion and incubated at 37 degrees C for 48 h. Bacterial growth was checked by turbidity of the culture medium carried out in triplicate. No solution used as an irrigant over a 20-min contact time demonstrated an antimicrobial effect against E. faecalis. The irrigation of infected human root canals with ozonated water, 2.5% NaOCl, 2% chlorhexidine and the application of gaseous ozone for 20 min was not sufficient to inactivate E. faecalis.

  12. Ovariectomy-Induced Mitochondrial Oxidative Stress, Apoptosis, and Calcium Ion Influx Through TRPA1, TRPM2, and TRPV1 Are Prevented by 17β-Estradiol, Tamoxifen, and Raloxifene in the Hippocampus and Dorsal Root Ganglion of Rats.

    Science.gov (United States)

    Yazğan, Yener; Nazıroğlu, Mustafa

    2017-12-01

    Relative 17β-estradiol (E2) deprivation and excessive production of mitochondrial oxygen free radicals (OFRs) with a high amount of Ca2+ influx TRPA1, TRPM2, and TRPV1 activity is one of the main causes of neurodegenerative disease in postmenopausal women. In addition to the roles of tamoxifen (TMX) and raloxifene (RLX) in cancer and bone loss treatments, regulator roles in Ca2+ influx and mitochondrial oxidative stress in neurons have not been reported. The aim of this study was to evaluate whether TMX and RLX interactions with TRPA1, TRPM2, and TRPV1 in primary hippocampal (HPC) and dorsal root ganglion (DRG) neuron cultures of ovariectomized (OVX) rats. Forty female rats were divided into five groups: a control group, an OVX group, an OVX+E2 group, an OVX+TMX group, and an OVX+RLX group. The OVX+E2, OVX+TMX, and OVX+RLX groups received E2, TMX, and RLX, respectively, for 14 days after the ovariectomy. E2, ovariectomy-induced TRPA1, TRPM2, and TRPV1 current densities, as well as accumulation of cytosolic free Ca2+ in the neurons, were returned to the control levels by E2, TMX, and RLX treatments. In addition, E2, TMX, and RLX via modulation of TRPM2 and TRPV1 activity reduced ovariectomy-induced mitochondrial membrane depolarization, apoptosis, and cytosolic OFR production. TRPM2, TRPV1, PARP, and caspase-3 and caspase-9 expressions were also decreased in the neurons by the E2, TMX, and RLX treatments. In conclusion, we first reported the molecular effects of E2, TMX, and RLX on TRPA1, TRPM2, and TRPV1 channel activation in the OVX rats. In addition, we observed neuroprotective effects of E2, RLX, and TMX on oxidative and apoptotic injuries of the hippocampus and peripheral pain sensory neurons (DRGs) in the OVX rats. Graphical Abstract Possible molecular pathways of involvement of DEX in cerebral ischemia-induced apoptosis, oxidative stress, and calcium accumulation through TRPA1, TRPM2 and TRPV1 in the hippocampus and DRG neurons of rats. The N domain of the

  13. Metabolomics of Neurotransmitters and Related Metabolites in Post-Mortem Tissue from the Dorsal and Ventral Striatum of Alcoholic Human Brain.

    Science.gov (United States)

    Kashem, Mohammed Abul; Ahmed, Selina; Sultana, Nilufa; Ahmed, Eakhlas U; Pickford, Russell; Rae, Caroline; Šerý, Omar; McGregor, Iain S; Balcar, Vladimir J

    2016-02-01

    We report on changes in neurotransmitter metabolome and protein expression in the striatum of humans exposed to heavy long-term consumption of alcohol. Extracts from post mortem striatal tissue (dorsal striatum; DS comprising caudate nucleus; CN and putamen; P and ventral striatum; VS constituted by nucleus accumbens; NAc) were analysed by high performance liquid chromatography coupled with tandem mass spectrometry. Proteomics was studied in CN by two-dimensional gel electrophoresis followed by mass-spectrometry. Proteomics identified 25 unique molecules expressed differently by the alcohol-affected tissue. Two were dopamine-related proteins and one a GABA-synthesizing enzyme GAD65. Two proteins that are related to apoptosis and/or neuronal loss (BiD and amyloid-β A4 precursor protein-binding family B member 3) were increased. There were no differences in the levels of dopamine (DA), 3,4-dihydrophenylacetic acid (DOPAC), serotonin (5HT), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (HIAA), histamine, L-glutamate (Glu), γ-aminobutyric acid (GABA), tyrosine (Tyr) and tryptophan (Tryp) between the DS (CN and P) and VS (NAc) in control brains. Choline (Ch) and acetylcholine (Ach) were higher and norepinephrine (NE) lower, in the VS. Alcoholic striata had lower levels of neurotransmitters except for Glu (30 % higher in the alcoholic ventral striatum). Ratios of DOPAC/DA and HIAA/5HT were higher in alcoholic striatum indicating an increase in the DA and 5HT turnover. Glutathione was significantly reduced in all three regions of alcohol-affected striatum. We conclude that neurotransmitter systems in both the DS (CN and P) and the VS (NAc) were significantly influenced by long-term heavy alcohol intake associated with alcoholism.

  14. Cost-Utility Analysis of 1- and 2-Level Dorsal Lumbar Fusions With and Without Recombinant Human Bone Morphogenic Protein-2 at 1-Year Follow-Up.

    Science.gov (United States)

    Alvin, Matthew D; Derakhshan, Adeeb; Lubelski, Daniel; Abdullah, Kalil G; Whitmore, Robert G; Benzel, Edward C; Mroz, Thomas E

    2016-02-01

    A retrospective 1-year cost-utility analysis. To determine the cost-effectiveness of using recombinant human bone morphogenic protein (rhBMP-2) in addition to autograft for 1- and 2-level lumbar fusions. rhBMP-2 has been studied extensively to identify its benefits, risks, patient outcomes, and costs relative to autograft [local bone or iliac crest bone graft (ICBG)]. This study seeks to analyze the cost-effectiveness of adding rhBMP-2 to autograft versus without rhBMP-2 in lumbar fusions. Thirty-three patients receiving rhBMP-2 in addition to either local bone autograft or ICBG (rhBMP-2 cohort) and 42 patients receiving only local bone autograft or ICBG (control cohort) for 1- or 2-level dorsal lumbar fusion were analyzed. This included posterolateral fusion, posterior lumbar interbody fusion, and transforaminal lumbar interbody fusion. One-year postoperative health outcomes were assessed based on Visual Analogue Scale, Pain Disability Questionnaire, Patient Health Questionnaire, and EuroQol-5 Dimensions questionnaires. Direct medical costs were estimated using Medicare national payment amounts and indirect costs were based on patient missed work days and patient income. Postoperative 1-year cost-utility ratios and the incremental cost-effectiveness ratio (ICER) were calculated to assess for cost-effectiveness using a threshold of $100,000/QALY gained. The 1-year cost-utility ratio (total cost/ΔQALY) for the control cohort was significantly lower ($143,251/QALY gained) than that of the rhBMP-2 cohort ($272,414/QALY gained) (Panalysis, the control cohort dominated the rhBMP-2 group. Assuming durable per year gains in QALY, by 2 years fusion with autograft but without rhBMP-2 would be considered cost-effective ($71,625/QALY gained), whereas fusion with both autograft and rhBMP-2 would not be cost-effective ($136,207/QALY gained).

  15. Hairy-root organ cultures for the production of human acetylcholinesterase

    Science.gov (United States)

    Woods, Ryan R; Geyer, Brian C; Mor, Tsafrir S

    2008-01-01

    Background Human cholinesterases can be used as a bioscavenger of organophosphate toxins used as pesticides and chemical warfare nerve agents. The practicality of this approach depends on the availability of the human enzymes, but because of inherent supply and regulatory constraints, a suitable production system is yet to be identified. Results As a promising alternative, we report the creation of "hairy root" organ cultures derived via Agrobacterium rhizogenes-mediated transformation from human acetylcholinesterase-expressing transgenic Nicotiana benthamiana plants. Acetylcholinesterase-expressing hairy root cultures had a slower growth rate, reached to the stationary phase faster and grew to lower maximal densities as compared to wild type control cultures. Acetylcholinesterase accumulated to levels of up to 3.3% of total soluble protein, ~3 fold higher than the expression level observed in the parental plant. The enzyme was purified to electrophoretic homogeneity. Enzymatic properties were nearly identical to those of the transgenic plant-derived enzyme as well as to those of mammalian cell culture derived enzyme. Pharmacokinetic properties of the hairy-root culture derived enzyme demonstrated a biphasic clearing profile. We demonstrate that master banking of plant material is possible by storage at 4°C for up to 5 months. Conclusion Our results support the feasibility of using plant organ cultures as a successful alternative to traditional transgenic plant and mammalian cell culture technologies. PMID:19105816

  16. Hairy-root organ cultures for the production of human acetylcholinesterase

    Directory of Open Access Journals (Sweden)

    Mor Tsafrir S

    2008-12-01

    Full Text Available Abstract Background Human cholinesterases can be used as a bioscavenger of organophosphate toxins used as pesticides and chemical warfare nerve agents. The practicality of this approach depends on the availability of the human enzymes, but because of inherent supply and regulatory constraints, a suitable production system is yet to be identified. Results As a promising alternative, we report the creation of "hairy root" organ cultures derived via Agrobacterium rhizogenes-mediated transformation from human acetylcholinesterase-expressing transgenic Nicotiana benthamiana plants. Acetylcholinesterase-expressing hairy root cultures had a slower growth rate, reached to the stationary phase faster and grew to lower maximal densities as compared to wild type control cultures. Acetylcholinesterase accumulated to levels of up to 3.3% of total soluble protein, ~3 fold higher than the expression level observed in the parental plant. The enzyme was purified to electrophoretic homogeneity. Enzymatic properties were nearly identical to those of the transgenic plant-derived enzyme as well as to those of mammalian cell culture derived enzyme. Pharmacokinetic properties of the hairy-root culture derived enzyme demonstrated a biphasic clearing profile. We demonstrate that master banking of plant material is possible by storage at 4°C for up to 5 months. Conclusion Our results support the feasibility of using plant organ cultures as a successful alternative to traditional transgenic plant and mammalian cell culture technologies.

  17. Right dorsal colitis.

    Science.gov (United States)

    Karcher, L F; Dill, S G; Anderson, W I; King, J M

    1990-01-01

    Moderate to severe ulcerative colitis of the right dorsal colon was diagnosed by necropsy or by exploratory celiotomy and biopsy in 13 horses with a primary clinical complaint of either colic, diarrhea, or weight loss. Clinical signs varied from acute fulminating diarrhea (possibly with fever), colic, dehydration, endotoxic shock and death, to a chronic condition manifested by mild intermittent colic up to several months in duration, and weight loss with or without mild diarrhea. In a large percentage of the horses, those affected had been hypovolemic and received nonsteroidal anti-inflammatory drugs (NSAID) or had received inappropriately high doses of phenylbutazone before the onset of illness. Experimental treatment of two horses with high doses of a phenylbutazone oral paste preparation (6 gm once daily for 5 days) and limitation of their water intake to approximately one half of maintenance requirement (for 5 days) resulted in reproduction of ulcerative colitis involving only the right dorsal colon, which was apparent at necropsy examination 11 and 15 days after initiation of drug use. It was concluded that localized ulcerative lesions in the right dorsal colon may be a previously unreported manifestation of toxicity due to the administration of NSAID.

  18. Human tooth and root canal morphology reconstruction using magnetic resonance imaging

    Science.gov (United States)

    DRĂGAN, OANA CARMEN; FĂRCĂŞANU, ALEXANDRU ŞTEFAN; CÂMPIAN, RADU SEPTIMIU; TURCU, ROMULUS VALERIU FLAVIU

    2016-01-01

    Background and aims Visualization of the internal and external root canal morphology is very important for a successful endodontic treatment; however, it seems to be difficult considering the small size of the tooth and the complexity of the root canal system. Film-based or digital conventional radiographic techniques as well as cone beam computed tomography provide limited information on the dental pulp anatomy or have harmful effects. A new non-invasive diagnosis tool is magnetic resonance imaging, due to its ability of imaging both hard and soft tissues. The aim of this study was to demonstrate magnetic resonance imaging to be a useful tool for imaging the anatomic conditions of the external and internal root canal morphology for endodontic purposes. Methods The endodontic system of one freshly extracted wisdom tooth, chosen for its well-known anatomical variations, was mechanically shaped using a hybrid technique. After its preparation, the tooth was immersed into a recipient with saline solution and magnetic resonance imaged immediately. A Bruker Biospec magnetic resonance imaging scanner operated at 7.04 Tesla and based on Avance III radio frequency technology was used. InVesalius software was employed for the 3D reconstruction of the tooth scanned volume. Results The current ex-vivo experiment shows the accurate 3D volume rendered reconstruction of the internal and external morphology of a human extracted and endodontically treated tooth using a dataset of images acquired by magnetic resonance imaging. The external lingual and vestibular views of the tooth as well as the occlusal view of the pulp chamber, the access cavity, the distal canal opening on the pulp chamber floor, the coronal third of the root canals, the degree of root separation and the apical fusion of the two mesial roots, details of the apical region, root canal curvatures, furcal region and interradicular root grooves could be clearly bordered. Conclusions Magnetic resonance imaging offers 3

  19. Human tooth and root canal morphology reconstruction using magnetic resonance imaging.

    Science.gov (United States)

    Drăgan, Oana Carmen; Fărcăşanu, Alexandru Ştefan; Câmpian, Radu Septimiu; Turcu, Romulus Valeriu Flaviu

    2016-01-01

    Visualization of the internal and external root canal morphology is very important for a successful endodontic treatment; however, it seems to be difficult considering the small size of the tooth and the complexity of the root canal system. Film-based or digital conventional radiographic techniques as well as cone beam computed tomography provide limited information on the dental pulp anatomy or have harmful effects. A new non-invasive diagnosis tool is magnetic resonance imaging, due to its ability of imaging both hard and soft tissues. The aim of this study was to demonstrate magnetic resonance imaging to be a useful tool for imaging the anatomic conditions of the external and internal root canal morphology for endodontic purposes. The endodontic system of one freshly extracted wisdom tooth, chosen for its well-known anatomical variations, was mechanically shaped using a hybrid technique. After its preparation, the tooth was immersed into a recipient with saline solution and magnetic resonance imaged immediately. A Bruker Biospec magnetic resonance imaging scanner operated at 7.04 Tesla and based on Avance III radio frequency technology was used. InVesalius software was employed for the 3D reconstruction of the tooth scanned volume. The current ex-vivo experiment shows the accurate 3D volume rendered reconstruction of the internal and external morphology of a human extracted and endodontically treated tooth using a dataset of images acquired by magnetic resonance imaging. The external lingual and vestibular views of the tooth as well as the occlusal view of the pulp chamber, the access cavity, the distal canal opening on the pulp chamber floor, the coronal third of the root canals, the degree of root separation and the apical fusion of the two mesial roots, details of the apical region, root canal curvatures, furcal region and interradicular root grooves could be clearly bordered. Magnetic resonance imaging offers 3D image datasets with more information than the

  20. Dorsal and Ventral Pathways for Prosody.

    Science.gov (United States)

    Sammler, Daniela; Grosbras, Marie-Hélène; Anwander, Alfred; Bestelmeyer, Patricia E G; Belin, Pascal

    2015-12-07

    Our vocal tone--the prosody--contributes a lot to the meaning of speech beyond the actual words. Indeed, the hesitant tone of a "yes" may be more telling than its affirmative lexical meaning. The human brain contains dorsal and ventral processing streams in the left hemisphere that underlie core linguistic abilities such as phonology, syntax, and semantics. Whether or not prosody--a reportedly right-hemispheric faculty--involves analogous processing streams is a matter of debate. Functional connectivity studies on prosody leave no doubt about the existence of such streams, but opinions diverge on whether information travels along dorsal or ventral pathways. Here we show, with a novel paradigm using audio morphing combined with multimodal neuroimaging and brain stimulation, that prosody perception takes dual routes along dorsal and ventral pathways in the right hemisphere. In experiment 1, categorization of speech stimuli that gradually varied in their prosodic pitch contour (between statement and question) involved (1) an auditory ventral pathway along the superior temporal lobe and (2) auditory-motor dorsal pathways connecting posterior temporal and inferior frontal/premotor areas. In experiment 2, inhibitory stimulation of right premotor cortex as a key node of the dorsal stream decreased participants' performance in prosody categorization, arguing for a motor involvement in prosody perception. These data draw a dual-stream picture of prosodic processing that parallels the established left-hemispheric multi-stream architecture of language, but with relative rightward asymmetry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Effect of Gamma Radiation and Endodontic Treatment on Mechanical Properties of Human and Bovine Root Dentin.

    Science.gov (United States)

    Novais, Veridiana Resende; Soares, Priscilla Barbosa Ferreira; Guimarães, Carlla Martins; Schliebe, Laís Rani Sales Oliveira; Braga, Stella Sueli Lourenço; Soares, Carlos José

    2016-01-01

    This study evaluated the effect of gamma radiation and endodontic treatment on the microhardness and flexural strength of human and bovine root dentin. Forty single-rooted human teeth and forty bovine incisor teeth were collected, cleaned and stored in distilled water at 4 °C. The human and bovine teeth were divided into 4 groups (n=10) resulting from the combination of two study factors: first, regarding the endodontic treatment in 2 levels: with or without endodontic treatment; and second, radiotherapy in two levels: with or without radiotherapy by 60 Gy of Co-60 gamma radiation fractioned into 2 Gy daily doses five days per week. Each tooth was longitudinally sectioned in two parts; one-half was used for the three-point bending test and the other for the Knoop hardness test (KHN). Data were analyzed by 3-way ANOVA and Tukey HSD test (α=0.05). No significant difference was found for flexural strength values. The human dentin had significantly higher KHN than the bovine. The endodontic treatment and radiotherapy resulted in significantly lower KHN irrespective of tooth origin. The results indicated that the radiotherapy had deleterious effects on the microhardness of human and bovine dentin and this effect is increased by the interaction with endodontic therapy. The endodontic treatment adds additional negative effect on the mechanical properties of radiated tooth dentin; the restorative protocols should be designed taking into account this effect.

  2. Effect of gamma radiation and endodontic treatment on mechanical properties of human and bovine root dentin

    Energy Technology Data Exchange (ETDEWEB)

    Novais, Veridiana Resende; Soares, Priscilla Barbosa Ferreira; Guimaraes, Carlla Martins; Schliebe, Lais Rani Sales Oliveira; Braga, Stella Sueli Lourenco; Soares, Carlos Jose, E-mail: carlosjsoares@ufu.br [Universidade Federal de Uberlandia (UFU), MG (Brazil)

    2016-11-15

    This study evaluated the effect of gamma radiation and endodontic treatment on the microhardness and flexural strength of human and bovine root dentin. Forty single rooted human teeth and forty bovine incisor teeth were collected, cleaned and stored in distilled water at 4 °C. The human and bovine teeth were divided into 4 groups (n=10) resulting from the combination of two study factors: first, regarding the endodontic treatment in 2 levels: with or without endodontic treatment; and second, radiotherapy in two levels: with or without radiotherapy by 60 Gy of Co-60 gamma radiation fractioned into 2 Gy daily doses five days per week. Each tooth was longitudinally sectioned in two parts; one-half was used for the three-point bending test and the other for the Knoop hardness test (KHN). Data were analyzed by 3-way ANOVA and Tukey HSD test (α=0.05). No significant difference was found for flexural strength values. The human dentin had significantly higher KHN than the bovine. The endodontic treatment and radiotherapy resulted in significantly lower KHN irrespective of tooth origin. The results indicated that the radiotherapy had deleterious effects on the microhardness of human and bovine dentin and this effect is increased by the interaction with endodontic therapy. The endodontic treatment adds additional negative effect on the mechanical properties of radiated tooth dentin; the restorative protocols should be designed taking into account this effect. (author)

  3. Withania somnifera Root Extract Has Potent Cytotoxic Effect against Human Malignant Melanoma Cells.

    Directory of Open Access Journals (Sweden)

    Babli Halder

    Full Text Available In Ayurveda, Withania somnifera is commonly known as Ashwagandha, its roots are specifically used in medicinal and clinical applications. It possesses numerous therapeutic actions which include anti-inflammatory, sedative, hypnotic and narcotic. Extracts from this plant have been reported for its anticancer properties. In this study we evaluated for the first time, the cytotoxic effect of Withania root extract on human malignant melanoma A375 cells. The crude extract of Withania was tested for cytotoxicity against A375 cells by MTT assay. Cell morphology of treated A375 cells was visualized through phase contrast as well as fluorescence microscopy. Agarose gel electrophoresis was used to check DNA fragmentation of the crude extract treated cells. Crude extract of Withania root has the potency to reduce viable cell count in dose as well as time dependent manner. Morphological change of the A375 cells was also observed in treated groups in comparison to untreated or vehicle treated control. Apoptotic body and nuclear blebbing were observed in DAPI stained treated cells under fluorescence microscope. A ladder of fragmented DNA was noticed in treated cells. Thus it might be said that the crude water extract of Withania somnifera has potent cytotoxic effect on human malignant melanoma A375 cells.

  4. Withania somnifera Root Extract Has Potent Cytotoxic Effect against Human Malignant Melanoma Cells.

    Science.gov (United States)

    Halder, Babli; Singh, Shruti; Thakur, Suman S

    2015-01-01

    In Ayurveda, Withania somnifera is commonly known as Ashwagandha, its roots are specifically used in medicinal and clinical applications. It possesses numerous therapeutic actions which include anti-inflammatory, sedative, hypnotic and narcotic. Extracts from this plant have been reported for its anticancer properties. In this study we evaluated for the first time, the cytotoxic effect of Withania root extract on human malignant melanoma A375 cells. The crude extract of Withania was tested for cytotoxicity against A375 cells by MTT assay. Cell morphology of treated A375 cells was visualized through phase contrast as well as fluorescence microscopy. Agarose gel electrophoresis was used to check DNA fragmentation of the crude extract treated cells. Crude extract of Withania root has the potency to reduce viable cell count in dose as well as time dependent manner. Morphological change of the A375 cells was also observed in treated groups in comparison to untreated or vehicle treated control. Apoptotic body and nuclear blebbing were observed in DAPI stained treated cells under fluorescence microscope. A ladder of fragmented DNA was noticed in treated cells. Thus it might be said that the crude water extract of Withania somnifera has potent cytotoxic effect on human malignant melanoma A375 cells.

  5. Temperature evolution on human teeth root surface after diode laser assisted endodontic treatment.

    Science.gov (United States)

    Gutknecht, Norbert; Franzen, Rene; Meister, Jörg; Vanweersch, Leon; Mir, Maziar

    2005-09-01

    The thermal rise threshold of an 810-nm semi-conductor diode laser on the root surface when used in root canals in vitro for laser assisted root canal treatment is investigated in this study. A total of 50 human single-rooted extracted teeth were included. For this study, the canals were enlarged up to an apical size of ISO#50 file. Laser irradiation was performed with six different settings. Specimens were irradiated at 0.6-1 W output power at the distal end of the fiber and about 1-1.5 W output power in the continuous mode (CW) as two groups. In the third group, 0.6-1 W output power, 10 ms pulse length (PL) and 10 ms interval duration (ID) were selected. In three other groups 1-1.5 W output power were used with different PL and ID as following: PL 10 and ID 10 ms, PL 10 and ID 20 ms and PL 20 and ID 20 ms. The total irradiation time was from 5 to 20 s per canal with a 200 mum in diameter and 25 mm long tip. After laser treatment, the temperature changes at the outer root surface were registered by means of NiCr-Ni measuring sensors and a T 202 thermometer. The safe temperature threshold for applying this diode laser in root canal is considered as 7 degrees C increase. To avoid increasing the temperature changes at the outer root surface related to this threshold, following total irradiation times were found: 0.6-1 W output power (10 ms PL/10 ms ID): 20 s (s), 1-1.5 W output power (10 ms/10 ms and 20 ms/20 ms): 15 s, 0.6-1 W output power CW and 1-1.5 W output power (20 ms PL/10 ms ID): 10 s and 1-1.5 W output power CW: 5 s. In the first three groups, 5 s irradiation and 5 s rest period avoided a temperature increase above the threshold of 7 degrees C).

  6. Irrigation of human prepared root canal – ex vivo based computational fluid dynamics analysis

    Science.gov (United States)

    Šnjarić, Damir; Čarija, Zoran; Braut, Alen; Halaji, Adelaida; Kovačević, Maja; Kuiš, Davor

    2012-01-01

    Aim To analyze the influence of the needle type, insertion depth, and irrigant flow rate on irrigant flow pattern, flow velocity, and apical pressure by ex-vivo based endodontic irrigation computational fluid dynamics (CFD) analysis. Methods Human upper canine root canal was prepared using rotary files. Contrast fluid was introduced in the root canal and scanned by computed tomography (CT) providing a three-dimensional object that was exported to the computer-assisted design (CAD) software. Two probe points were established in the apical portion of the root canal model for flow velocity and pressure measurement. Three different CAD models of 27G irrigation needles (closed-end side-vented, notched open-end, and bevel open-end) were created and placed at 25, 50, 75, and 95% of the working length (WL). Flow rates of 0.05, 0.1, 0.2, 0.3, and 0.4 mL/s were simulated. A total of 60 irrigation simulations were performed by CFD fluid flow solver. Results Closed-end side-vented needle required insertion depth closer to WL, regarding efficient irrigant replacement, compared to open-end irrigation needle types, which besides increased velocity produced increased irrigant apical pressure. For all irrigation needle types and needle insertion depths, the increase of flow rate was followed by an increased irrigant apical pressure. Conclusions The human root canal shape obtained by CT is applicable in the CFD analysis of endodontic irrigation. All the analyzed values –irrigant flow pattern, velocity, and pressure – were influenced by irrigation needle type, as well as needle insertion depth and irrigant flow rate. PMID:23100209

  7. Effect of iRoot Fast Set root repair material on the proliferation, migration and differentiation of human dental pulp stem cells in vitro.

    Directory of Open Access Journals (Sweden)

    Yan Sun

    Full Text Available The present study investigated the effect of iRoot Fast Set root repair material (iRoot FS on the proliferation, migration and differentiation of human dental pulp stem cells (hDPSCs. The hDPSCs were treated with eluates of iRoot FS at concentrations of 0.2 and 2 mg/mL, referred to as FS0.2 and FS2, respectively, and Biodentine (BD; Septodont, Saint Maur des Faussés, France eluates at the corresponding concentrations as positive controls. A CCK8 assay was performed to determine cell proliferation. Wound healing and transwell assays were conducted to examine cell migration. Osteogenic differentiation was evaluated based on alkaline phosphatase activity, Alizarin Red S staining and quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR to analyze the mRNA expression of differentiation gene markers. Cell proliferation was higher in the FS and BD groups than in the blank controls at 3 and 7 days. Moreover, FS0.2 enhanced cell migration and significantly promoted the osteogenic differentiation of hDPSCs. These findings suggested that iRoot FS is a bioactive material that promotes the proliferation, migration and osteogenic differentiation of hDPSCs.

  8. [Changes in the expression of large-conductance calcium-activated potassium channels in dorsal root ganglion neurons after electrical injury in rats' sciatic nerves and its influence on sensory conduction function].

    Science.gov (United States)

    Wang, Guangning; Li, Xueyong; Xu, Xiaoli; Ren, Pan

    2016-06-01

    To study the changes in the expression of large-conductance calcium-activated potassium (BKCa) channels in dorsal root ganglion (DRG) neurons after electrical injury in rats' sciatic nerves and its influence on sensory conduction function. One-hundred and thirty-six adult SD rats were divided into normal control group, sham electrical injury group, and 75, 100, 125 V electrical injury groups according to the random number table, with 8 rats in normal control group and 32 rats in each of the rest 4 groups. Rats in normal control group were routinely fed without any treatment. Blunt dissection of the sciatic nerves of left hind leg of rats was performed in sham electrical injury group, while sciatic nerves of left hind leg of rats in electrical injury groups were electrically injured with corresponding voltage. Eight rats of normal control group fed for one week, and 8 rats from each of the rest four groups on post injury day (PID) 3 and in post injury week (PIW) 1, 2, 3 respectively were collected to detect the paw withdrawal mechanical threshold (PWMT). In addition, rats of 100 V electrical injury group in PIW 1 were collected and intrathecally injected with NS1619 after former PWMT detection, and PWMT was detected per 30 minutes within three hours post injection. The rats in each group at each time point were sacrificed after PWMT detection. The DRG of L4 to L6 segments of spinal cord was sampled to observe the BKCa channels distribution with immunohistochemical staining and to detect the protein and mRNA expressions of BKCa channels with Western blotting and reverse transcription-polymerase chain reaction respectively. Data were processed with one-way analysis of variance, analysis of variance of factorial design, and SNK test. (1) The PWMT values of rats in 75 and 100 V electrical injury groups on PID 3 and in PIW 1, 2, 3 were (5.8±0.6), (5.0±0.8), (4.2±0.3), (5.9±1.1) g; (5.3±1.3), (5.9±2.0), (4.5±2.7), (4.3±1.3) g, respectively, which were

  9. Monosynaptic connections between primary afferents and giant neurons in the turtle spinal dorsal horn

    DEFF Research Database (Denmark)

    Fernández, A; Radmilovich, M; Russo, R E

    1996-01-01

    This paper reports the occurrence of monosynaptic connections between dorsal root afferents and a distinct cell type-the giant neuron-deep in the dorsal horn of the turtle spinal cord. Light microscope studies combining Nissl stain and transganglionic HRP-labeling of the primary afferents have re...

  10. Selective growth inhibitor toward human intestinal bacteria derived from Pulsatilla cernua root.

    Science.gov (United States)

    Lee, H S; Beon, M S; Kim, M K

    2001-10-01

    Among 21 medicinal plants, the growth-inhibiting activity of Pulsatilla cernua root-derived materials toward human intestinal bacteria was examined by using an impregnated paper disk method. The biologically active components of P. cernua roots were characterized as 4-hydroxy-3-methoxycinnamic acid and 3,4-dihydroxycinnamic acid by spectroscopic analysis. The activity was compared with that of six commercially available cinnamic acid derivatives trans-cinnamaldehyde, trans-cinnamic acid, cinnamyl alcohol, 2-methoxycinnamic acid, 3-methoxycinnamic acid, and 4-methoxycinnamic acid. The growth responses varied with each bacterial strain tested. Two isolated compounds revealed a potent inhibition against Clostridium perfringens, and moderate to weak activity against Escherichia coli was exhibited by 4-hydroxy-3-methoxycinnamic acid. Weak or no inhibitory activity was obtained against the bifidobacteria or Lactobacillus acidophilus. The inhibitory effect was much more pronounced in C. perfringens and E. coli as compared to B. adolescentis, B. bifidum, B. fragilis, B. longum, or L. acidophilus. Cinnamaldehyde exhibited a strong growth-inhibiting activity, but no inhibition was observed from treatments with trans-cinnamic acid, cinnamyl alcohol, 2-methoxycinnamic acid, 3-methoxycinnamic acid, and 4-methoxycinnamic acid. These results may be an indication of at least one of the pharmacological actions of P. cernua root.

  11. Effect of an herb root extract, herbal dentifrice and synthetic dentifrice on human salivary amylase.

    Science.gov (United States)

    Sapra, Gaurav; Vyas, Yogesh Kumar; Agarwal, Rahul; Aggarwal, Ashish; Chandrashekar, K T; Sharma, Kanika

    2013-07-01

    Salivary amylase is an enzyme, which plays a vital role in formation of dental plaque. It has the ability to bind on the bacterial surfaces and to hydrolyze starch, giving rise to products that are transformed into acids leading to dental caries. Suppression of salivary amylase activity can lead to decrease in risk of dental caries and plaque associated periodontal diseases. The aim of this study was to evaluate the effect of an herb, Spilanthes calva (in form of a test dentifrice) on human salivary amylase activity and to compare it with other dentifrices. A total of 80 subjects of age 18-35 years were randomly selected and divided equally into 4 groups. Group 1 subjects were assigned to use Test Dentifrice (with S. calva root extract), while Group 2, Group 3, and Group 4 subjects were assigned to use Herbal Dentifrice (Arodent(™)), Synthetic Dentifrice (Colgate(®)), and Control Dentifrice respectively. Salivary amylase activity was determined by Bernfeld method in each group, before and after using the given dentifrices. Maximum inhibition of salivary amylase activity was found in the group using test dentifrice as compared to others. The present study indicates that, the root extract of S. calva possess significant inhibitory activity for salivary amylase. Use of S. calva root extract will provide a wider protection against different pathogenic oral microflora. Use of this extract singly or in combination is strongly recommended in the dentifrice formulations.

  12. Effect of an herb root extract, herbal dentifrice and synthetic dentifrice on human salivary amylase

    Science.gov (United States)

    Sapra, Gaurav; Vyas, Yogesh Kumar; Agarwal, Rahul; Aggarwal, Ashish; Chandrashekar, K T; Sharma, Kanika

    2013-01-01

    Background: Salivary amylase is an enzyme, which plays a vital role in formation of dental plaque. It has the ability to bind on the bacterial surfaces and to hydrolyze starch, giving rise to products that are transformed into acids leading to dental caries. Suppression of salivary amylase activity can lead to decrease in risk of dental caries and plaque associated periodontal diseases. The aim of this study was to evaluate the effect of an herb, Spilanthes calva (in form of a test dentifrice) on human salivary amylase activity and to compare it with other dentifrices. Materials and Methods: A total of 80 subjects of age 18-35 years were randomly selected and divided equally into 4 groups. Group 1 subjects were assigned to use Test Dentifrice (with S. calva root extract), while Group 2, Group 3, and Group 4 subjects were assigned to use Herbal Dentifrice (Arodent™), Synthetic Dentifrice (Colgate®), and Control Dentifrice respectively. Salivary amylase activity was determined by Bernfeld method in each group, before and after using the given dentifrices. Results: Maximum inhibition of salivary amylase activity was found in the group using test dentifrice as compared to others. Conclusion: The present study indicates that, the root extract of S. calva possess significant inhibitory activity for salivary amylase. Use of S. calva root extract will provide a wider protection against different pathogenic oral microflora. Use of this extract singly or in combination is strongly recommended in the dentifrice formulations. PMID:24130585

  13. Preliminary observations on increasing root length during the eruptive phase of tooth development in modern humans and great apes.

    Science.gov (United States)

    Dean, M Christopher; Vesey, Peter

    2008-02-01

    Ground sections of incisors, canines, and molars were selected that showed clear incremental markings in root dentine. The sample comprised 98 Homo sapiens, 53 Pan troglodytes, and a more limited combined sample of 51 Gorilla and Pongo sections. Daily rates of root dentine formation, together with the orientation of incremental markings in roots close to the cement-dentine junction (CDJ), were used to calculate root extension rates for the first 10mm of root formed beyond the buccal enamel cervix. Modern human anterior tooth roots showed a more regular pattern of increase in root length than those in great apes. In Pan, root growth rose quickly to higher rates but then flattened off. The fastest extension rates in modern humans were in incisor roots (10-12 microm per day), followed by canines (8-9 microm per day). Extension rates in Pan rose to slightly greater values in canines ( approximately 12-14 microm per day) than in incisors ( approximately 10-11 microm per day). Molar tooth roots in both modern humans and great apes grew in a nonlinear manner. Peak rates in molars reduced from M1 to M3 (8, 7, and 6 microm per day, respectively). Like humans, root growth in Pan peaked earlier in M1s at rates of between 8 and 9 microm per day, and later in M3s at rates of 7 to 8 microm per day. The more limited data set for Gorilla and Pongo molars suggests that extension rates were generally higher than in Pan by approximately 1.0-1.5 microm per day. There were greater differences in peak extension rates, with Gorilla and Pongo extension rates being between 2.5 and 4.5 microm per day higher than those in Pan. These findings highlight for the first time that root growth rates differ between tooth types in both pattern and rate and between taxa. They provide the basis with which to explore further the potential comparative relationships between root growth, jaw growth, and the eruption process.

  14. Effect of laser treatment on the root canal of human teeth.

    Science.gov (United States)

    Khan, M A; Khan, M F; Khan, M W; Wakabayashi, H; Matsumoto, K

    1997-06-01

    The purpose of this study was to examine the morphological and temperature changes of the apical portion of human extracted teeth treated by Nd: YAG, CO2 and Argon-lasers. Seventy-two single-rooted human teeth were studied. The root canals were prepared conventionally. Laser treatment of the apical portion of the canal was carried out by means of an optic fiber or metal tip. Temperatures were recorded thermographically. Two-thirds of the specimens were stained with black India ink and 36% silver ammonium fluoride solution. All specimens were irradiated by the three types of lasers at several intensities and the temperatures were recorded. Half of the specimens were prepared for the telescopic light microscope and for scanning electron microscopic observation, and the rest for histopathological examination by light microscope. The scanning electron microscopic evaluation showed that the laser energy vaporized the deposited debris, producing a glaze-like surface. The histopathological investigation revealed a tapered, enlarged apical lased area. All three laser devices were capable of vaporizing the debris in this way but the degree of morphological change was highly dependent on energy level and duration. The Argon-laser produced the highest temperatures.

  15. Pulp regeneration in a full-length human tooth root using a hierarchical nanofibrous microsphere system.

    Science.gov (United States)

    Li, Xiangwei; Ma, Chi; Xie, Xiaohua; Sun, Hongchen; Liu, Xiaohua

    2016-04-15

    While pulp regeneration using tissue engineering strategy has been explored for over a decade, successful regeneration of pulp tissues in a full-length human root with a one-end seal that truly simulates clinical endodontic treatment has not been achieved. To address this challenge, we designed and synthesized a unique hierarchical growth factor-loaded nanofibrous microsphere scaffolding system. In this system, vascular endothelial growth factor (VEGF) binds with heparin and is encapsulated in heparin-conjugated gelatin nanospheres, which are further immobilized in the nanofibers of an injectable poly(l-lactic acid) (PLLA) microsphere. This hierarchical microsphere system not only protects the VEGF from denaturation and degradation, but also provides excellent control of its sustained release. In addition, the nanofibrous PLLA microsphere integrates the extracellular matrix-mimicking architecture with a highly porous injectable form, efficiently accommodating dental pulp stem cells (DPSCs) and supporting their proliferation and pulp tissue formation. Our in vivo study showed the successful regeneration of pulp-like tissues that fulfilled the entire apical and middle thirds and reached the coronal third of the full-length root canal. In addition, a large number of blood vessels were regenerated throughout the canal. For the first time, our work demonstrates the success of pulp tissue regeneration in a full-length root canal, making it a significant step toward regenerative endodontics. The regeneration of pulp tissues in a full-length tooth root canal has been one of the greatest challenges in the field of regenerative endodontics, and one of the biggest barriers for its clinical application. In this study, we developed a unique approach to tackle this challenge, and for the first time, we successfully regenerated living pulp tissues in a full-length root canal, making it a significant step toward regenerative endodontics. This study will make positive scientific

  16. In vitro performance of DIAGNOdent laser fluorescence device for dental calculus detection on human tooth root surfaces.

    Science.gov (United States)

    Rams, Thomas E; Alwaqyan, Abdulaziz Y

    2017-10-01

    This study assessed the reproducibility of a red diode laser device, and its capability to detect dental calculus in vitro on human tooth root surfaces. On each of 50 extracted teeth, a calculus-positive and calculus-free root surface was evaluated by two independent examiners with a low-power indium gallium arsenide phosphide diode laser (DIAGNOdent) fitted with a periodontal probe-like sapphire tip and emitting visible red light at 655 nm wavelength. Laser autofluorescence intensity readings of examined root surfaces were scored on a 0-99 scale, with duplicate assessments performed using the laser probe tip directed both perpendicular and parallel to evaluated tooth root surfaces. Pearson correlation coefficients of untransformed measurements, and kappa analysis of data dichotomized with a >40 autofluorescence intensity threshold, were calculated to assess intra- and inter-examiner reproducibility of the laser device. Mean autofluorescence intensity scores of calculus-positive and calculus-free root surfaces were evaluated with the Student's t -test. Excellent intra- and inter-examiner reproducibility was found for DIAGNOdent laser autofluorescence intensity measurements, with Pearson correlation coefficients above 94%, and kappa values ranging between 0.96 and 1.0, for duplicate readings taken with both laser probe tip orientations. Significantly higher autofluorescence intensity values were measured when the laser probe tip was directed perpendicular, rather than parallel, to tooth root surfaces. However, calculus-positive roots, particularly with calculus in markedly-raised ledges, yielded significantly greater mean DIAGNOdent laser autofluorescence intensity scores than calculus-free surfaces, regardless of probe tip orientation. DIAGNOdent autofluorescence intensity values >40 exhibited a stronger association with calculus (36.6 odds ratio) then measurements of ≥5 (20.1 odds ratio) when the laser probe tip was advanced parallel to root surfaces. Excellent

  17. The effect of root planing and citric acid applications on flap healing in humans. A histologic evaluation.

    Science.gov (United States)

    Kashani, H G; Magner, A W; Stahl, S S

    1984-12-01

    Four human teeth and their facial gingival attachment were removed en block 3 months after periodontal flap therapy and citric acid root conditioning and then prepared for histologic evaluation. At the time of periodontal surgery, and prior to citric acid application, the facial root surface was grooved at midline and citric acid was applied only to one-half of each root surface. Tissues were decalcified and histologically prepared as horizontally oriented, step serial sections from the level of the gingival margin to the level of the facial crest. The gingival margins demonstrated reformation of a crevice. The corium at this level showed a mild inflammatory infiltrate. Apical to this level, junctional epithelium adhered to both sides of the root surface and to the central groove. Further apically, supracrestal fiber groups were encountered. No new cementum was noted in these areas. Fiber attachment was present apical to this level. Since no new cementum was seen at this area of attachment, it may represent collagen attachment present prior to periodontal surgery. In the four specimens examined, no differences were seen in the soft tissue closures between the root-planed citric acid-treated root surfaces and root surfaces which received root planing alone.

  18. Bursting deep dorsal horn neurons

    DEFF Research Database (Denmark)

    Carlsen, Eva Meier; Rasmussen, Rune

    2017-01-01

    In a recent publication, Thaweerattanasinp et al. (J Neurophysiol 116: 1644–1653, 2016) investigated spinal cord injury and firing properties of deep dorsal horn neurons during NMDA or zolmitriptan application by employing electrophysiology in an in vitro spinal cord preparation. Deep dorsal horn...

  19. Effects of root canal sealers on alkaline phosphatase in human osteoblastic cells.

    Science.gov (United States)

    Huang, Fu-Mei; Yang, Shun-Fa; Chang, Yu-Chao

    2010-07-01

    Histologic investigations have demonstrated that root canal sealers can induce mild to severe bone resorption. Alkaline phosphatase (ALP) is a membrane-bound glycoprotein, which is one of the osteogenic differentiation markers considered to indicate the formation of new bone. The aim of this study was to investigate the effects of an epoxy resin-based sealer AH26, a zinc oxide-eugenol-based sealer Canals, and a paste sealer N2 on the expression of ALP in human osteoblastic cell line U2OS cells. Freshly mixed materials were filled in glass rings and eluted in 10 mL of culture medium for 1 day. Subsequently, various dilutions (final dilution: 1/2, 1/4, and 1/8) of these extraction media were prepared for this study. Cytotoxicity was measured by the almar blue dye assay. Gene expression of ALP was examined by using reverse transcription-polymerase chain reaction. ALP activity was further evaluated by using substrate assay. The results showed that AH26, Canals, and N2 were cytotoxic to U2OS cells in a concentration-dependent manner (P < .05). The exposure of U2OS cells to AH26 and N2 resulted in the down-regulation of ALP mRNA gene expression (P < .05). ALP activity was significantly suppressed by 3 root canal sealers (P < .05). The inhibition of ALP expression might play an important role in the pathogenesis of root canal sealer-induced periapical bone destruction. Crown Copyright 2010. Published by Elsevier Inc. All rights reserved.

  20. An in vitro scanning electron microscopic study comparing MTAD (intracanal irrigant and various root biomodifiers on periodontally involved human teeth

    Directory of Open Access Journals (Sweden)

    Charu Tandon

    2014-01-01

    Full Text Available Background: Smear layer removal and collagen fiber exposure may improve regeneration outcome, which can be accomplished by use of root biomodifiers. These enhance the degree of connective tissue attachment to denuded roots. The objective of this in vitro scanning electron microscopic study was to comparatively evaluate mixture of tetracycline (TTC and acid and detergent (MTAD and other root biomodifiers for smear layer removal on periodontally involved human teeth. Materials and Methods: Forty human teeth were collected and stored in saline. After scaling and root planning, two samples were obtained from each tooth. A total of 80 dentin blocks were randomly divided into four groups: MTAD, TTC hydrochloride (TTC HCl, citric acid (CA, and normal saline. The agents were applied for 3 min by active burnishing. Immediately following treatment, the specimens were rinsed, dehydrated, fixed and prepared for scanning electron microscope and was examined at Χ3500 magnification. Previously trained blind examiners evaluated photomicrographs using Sampaio′s index (2005. Statistical analysis was performed. Results: MTAD is most efficacious in removing smear layer and showed statistically significant dentinal tubules opening, followed by TTC HCl and CA. Conclusion: MTAD and conventional root biomodifiers used in the study alters the dentin surface by smear layer removal and exposure of dentinal tubules. Hence, MTAD as a root biomodifier may have a significant role in periodontal regeneration .

  1. Neutrophilic dermatosis of dorsal hands

    Directory of Open Access Journals (Sweden)

    S Kaur

    2015-01-01

    Full Text Available Sweet′s syndrome is characterized by erythematous tender nodules and plaques over face and extremities. Fever, leukocytosis with neutrophilia, and a neutrophilic infiltrate in the dermis are characteristic features. Neutrophilic dermatosis of dorsal hands is a rare localized variant of Sweet′s syndrome occurring predominantly over dorsa of hands. Various degrees of vascular damage may be observed on histopathology of these lesions. Both Sweet′s syndrome and its dorsal hand variant have been reported in association with malignancies, inflammatory bowel diseases, and drugs. We report a patient with neutrophilic dermatoses of dorsal hands associated with erythema nodosum. He showed an excellent response to corticosteroids and dapsone.

  2. Soil-Root Processes Responsible for Arsenic Uptake in Rice: A Route of Human Exposure

    Science.gov (United States)

    Seyfferth, A.; Fendorf, S.

    2010-12-01

    Arsenic contamination of groundwater is causing the largest mass poisoning in history, but we are only beginning to understand the extent of human exposure through contaminated food. Although second to drinking water in terms of human exposure, the consumption of As-laden food, such as rice, can be a significant portion of daily As exposure especially for populations already exposed through drinking water. Arsenic contamination of soils and groundwater is widespread In South and Southeast Asia, which is also one of the largest rice-growing regions of the world. As the demand for food has increased, so too has the use of irrigation practices to meet food demand, and much of this is via water contaminated with arsenic. In order to accurately predict human exposure to arsenic through rice consumption, we must first understand the processes that affect As dynamics in the rhizosphere and thus uptake by rice. Here, we examine As cycling in the rhizosphere, As distribution on and uptake by rice roots, the influence of Fe dynamics on As uptake, and mitigation strategies to reduce concentrations of As in rice grains.

  3. Human teeth with periapical pathosis after overinstrumentation and overfilling of the root canals: a scanning electron microscopic study.

    Science.gov (United States)

    Gutiérrez, J H; Brizuela, C; Villota, E

    1999-01-01

    The aim of this study was to determine whether overinstrumentation followed by immediate overfilling could be a potential risk in the treatment of infected root canals. Thirty-five human teeth with infected root canals were overinstrumented and overfilled approximately 45 min after their extraction. The experimental teeth were enlarged up to size 40 and the overinstrumentation and overfilling were checked with the aid of a magnifying glass. The specimens were fixed in glutaraldehyde plus sodium cacodylate solution and prepared for scanning electron microscope examination. Bacteria were detected on the flute of the files and mostly at the root apices around the main foramen, remaining firmly attached to resorptive lacunae despite the fact that the apices had undergone great changes, including fracture or zipping. A control group consisting of 10 human teeth root canals containing vital pulps were also overinstrumented and overfilled. No bacteria were detected on the flutes of the files, at the apices or on the extruded master cone overfilling these samples. The high percentage of bacteria adhering to the resorptive lacunae or in the flutes of files used in overinstrumented human teeth with infected root canals carry a potential risk for postoperative pain, clinical discomfort and flare-ups. The hazards observed in these circumstances do not support the one-visit treatment of teeth having acute or chronic periapical abscesses.

  4. Cytocompatibility of Biodentine and iRoot FS with human periodontal ligament cells: an in vitro study.

    Science.gov (United States)

    Luo, T; Liu, J; Sun, Y; Shen, Y; Zou, L

    2018-01-19

    To evaluate the cytocompatibility of Biodentine and iRoot FS with human periodontal ligament cells (hPDLCs). Human periodontal ligament cells were characterized by flow cytometry and immunocytochemical analysis. Human periodontal ligament cell adhesion was assessed by scanning electron microscopy at day 3; proliferation by live/dead assay at days 1, 3 and 7; and osteogenic differentiation by alkaline phosphatase (ALP) activity staining, ALP quantification analysis and qRT-PCR at days 7 and 14. Data were analysed with anova and independent sample t-tests with SPSS 21.0. Both iRoot FS and Biodentine increased the adhesion of hPDLCs at day 3. Compared to Biodentine, iRoot FS positively increased hPDLC proliferation on days 3 (P = 0.03) and 7 (P = 0.00). Osteogenic marker ALP was observed consistently in all samples, with iRoot FS having significantly higher ALP activity at day 14 (P = 0.00). Compared with Biodentine, iRoot FS significantly increased the mRNA level of ALP, COL1 and Runx2, and OCN increased only on day 14 (P Biodentine. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  5. Biologically active recombinant human erythropoietin expressed in hairy root cultures and regenerated plantlets of Nicotiana tabacum L.

    Science.gov (United States)

    Gurusamy, Poornima Devi; Schäfer, Holger; Ramamoorthy, Siva; Wink, Michael

    2017-01-01

    Hairy root culture is a potential alternative to conventional mammalian cell culture to produce recombinant proteins due to its ease in protein recovery, low costs and absence of potentially human pathogenic contaminants. The current study focussed to develop a new platform of a hairy root culture system from Nicotiana tabacum for the production of recombinant human EPO (rhEPO), which is regularly produced in mammalian cells. The human EPO construct was amplified with C-terminal hexahistidine tag from a cDNA of Caco-2 cells. Two versions of rhEPO clones, with or without the N-terminal calreticulin (cal) fusion sequence, were produced by cloning the amplified construct into gateway binary vector pK7WG2D. Following Agrobacterium rhizogenes mediated transformation of tobacco explants; integration and expression of constructs in hairy roots were confirmed by several tests at DNA, RNA and protein levels. The amount of intracellular rhEPO from hairy root cultures with cal signal peptide was measured up to 66.75 ng g-1 of total soluble protein. The presence of the ER signal peptide (cal) was essential for the secretion of rhEPO into the spent medium; no protein was detected from hairy root cultures without ER signal peptide. The addition of polyvinylpyrrolidone enhanced the stabilization of secreted rhEPO leading to a 5.6 fold increase to a maximum concentration of 185.48 pg rhEPOHR g-1 FW hairy root cultures. The rhizo-secreted rhEPO was separated by HPLC and its biological activity was confirmed by testing distinct parameters for proliferation and survival in retinal pigment epithelial cells (ARPE). In addition, the rhEPO was detected to an amount 14.8 ng g-1 of total soluble leaf protein in transgenic T0 generation plantlets regenerated from hairy root cultures with cal signal peptide.

  6. Biologically active recombinant human erythropoietin expressed in hairy root cultures and regenerated plantlets of Nicotiana tabacum L.

    Directory of Open Access Journals (Sweden)

    Poornima Devi Gurusamy

    Full Text Available Hairy root culture is a potential alternative to conventional mammalian cell culture to produce recombinant proteins due to its ease in protein recovery, low costs and absence of potentially human pathogenic contaminants. The current study focussed to develop a new platform of a hairy root culture system from Nicotiana tabacum for the production of recombinant human EPO (rhEPO, which is regularly produced in mammalian cells. The human EPO construct was amplified with C-terminal hexahistidine tag from a cDNA of Caco-2 cells. Two versions of rhEPO clones, with or without the N-terminal calreticulin (cal fusion sequence, were produced by cloning the amplified construct into gateway binary vector pK7WG2D. Following Agrobacterium rhizogenes mediated transformation of tobacco explants; integration and expression of constructs in hairy roots were confirmed by several tests at DNA, RNA and protein levels. The amount of intracellular rhEPO from hairy root cultures with cal signal peptide was measured up to 66.75 ng g-1 of total soluble protein. The presence of the ER signal peptide (cal was essential for the secretion of rhEPO into the spent medium; no protein was detected from hairy root cultures without ER signal peptide. The addition of polyvinylpyrrolidone enhanced the stabilization of secreted rhEPO leading to a 5.6 fold increase to a maximum concentration of 185.48 pg rhEPOHR g-1 FW hairy root cultures. The rhizo-secreted rhEPO was separated by HPLC and its biological activity was confirmed by testing distinct parameters for proliferation and survival in retinal pigment epithelial cells (ARPE. In addition, the rhEPO was detected to an amount 14.8 ng g-1 of total soluble leaf protein in transgenic T0 generation plantlets regenerated from hairy root cultures with cal signal peptide.

  7. Neutrophilic dermatosis of dorsal hands

    OpenAIRE

    KAUR, S.; Gupta, D.; Garg, B; Sood, N.

    2015-01-01

    Sweet′s syndrome is characterized by erythematous tender nodules and plaques over face and extremities. Fever, leukocytosis with neutrophilia, and a neutrophilic infiltrate in the dermis are characteristic features. Neutrophilic dermatosis of dorsal hands is a rare localized variant of Sweet′s syndrome occurring predominantly over dorsa of hands. Various degrees of vascular damage may be observed on histopathology of these lesions. Both Sweet′s syndrome and its dorsal hand variant have been r...

  8. Calcium hydroxide has limited effectiveness in eliminating bacteria from human root canal.

    Science.gov (United States)

    Balto, Khaled A

    2007-01-01

    statistically significant difference between pre- and postmedicated canals, whereas two did not. There was considerable heterogeneity among studies. The pooled risk difference was 21% (95% confidence intervals, 6-47%. The difference in the proportion of cases positive for bacteria before and after treatment was not statistically significant (P = 0.12). Based on the current best available evidence, calcium hydroxide has limited effectiveness in eliminating bacteria from human root canals, when assessed by culture techniques. The quest for better antibacterial protocols and sampling techniques must continue to ensure that bacteria can be reliably eradicated prior to obturation.

  9. Effect of soluble and insoluble fibers within the in vitro fermentation of chicory root pulp by human gut bacteria

    NARCIS (Netherlands)

    Ramasamy, U.S.; Venema, K.; Schols, H.A.; Gruppen, H.

    2014-01-01

    The aim of this research was to study the in vitro fermentation of chicory root pulp (CRP) and ensiled CRP (ECRP) using human fecal inoculum. Analysis of carbohydrate levels in fermentation digests showed that 51% of all CRP carbohydrates were utilized after 24 h of fermentation. For ECRP, having

  10. Effect of Soluble and Insoluble Fibers within the in Vitro Fermentation of Chicory Root Pulp by Human Gut Bacteria

    NARCIS (Netherlands)

    Ramasamy, U.; Venema, K.; Schols, H.A.; Gruppen, H.

    2014-01-01

    The aim of this research was to study the in vitro fermentation of chicory root pulp (CRP) and ensiled CRP (ECRP) using human fecal inoculum. Analysis of carbohydrate levels in fermentation digests showed that 51% of all CRP carbohydrates were utilized after 24 h of fermentation. For ECRP, having

  11. Comparison of the Antibacterial Effect of Sodium Hypochlorite and Aloe Vera Solutions as Root Canal Irrigants in Human Extracted Teeth Contaminated with Enterococcus Faecalis

    OpenAIRE

    Sahebi S.; Khosravifar N.; SedighShamsi M.; Motamedifar M.

    2014-01-01

    Statement of Problem: The main purpose of a root canal treatment is to eliminate the bacteria and their products from the pulp space. Sodium hypochlorite has excellent antibacterial properties but also some negative features. Purpose: The aim of the present study is to compare the antimicrobial effect of Aloe Vera solution with sodium hypochlorite on E.faecalis in the root canals of human extracted teeth. Materials and Method: Sixty human extracted single rooted teeth were selected for...

  12. Cryopreserved human aortic root allografts arterial wall: Structural changes occurring during thawing.

    Directory of Open Access Journals (Sweden)

    Robert Novotny

    Full Text Available The aim of our experimental work was to assess morphological changes of arterial wall that arise during different thawing protocols of a cryopreserved human aortic root allograft (CHARA arterial wall.The experiment was performed on CHARAs. Two thawing protocols were tested: 1, CHARAs were thawed at a room temperature at +23°C; 2, CHARAs were placed directly into a water bath at +37°C.After fixation, all samples were washed in distilled water for 5 min, and dehydrated in a graded ethanol series (70, 85, 95, and 100% for 5 min at each level. The tissue samples were then immersed in 100% hexamethyldisilazane for 10 minutes and air dried in an exhaust hood at room temperature. Processed samples were mounted on stainless steel stubs, coated with gold.Thawing protocol 1: All 6 (100% samples showed loss of the endothelium and damage to the subendothelial layers with randomly dispersed circular defects and micro-fractures without smooth muscle cells contractions in the tunica media. Thawing protocol 2: All 6 (100% samples showed loss of endothelium from the luminal surface, longitudinal corrugations in the direction of blood flow caused by smooth muscle cells contractions in the tunica media with frequent fractures in the subendothelial layer.All the samples thawed at the room temperature showed smaller structural damage to the CHARA arterial wall with no smooth muscle cell contraction in tunica media when compared to the samples thawed in a water bath.

  13. Effect of an herb root extract, herbal dentifrice and synthetic dentifrice on human salivary amylase

    Directory of Open Access Journals (Sweden)

    Gaurav Sapra

    2013-01-01

    Conclusion: The present study indicates that, the root extract of S. calva possess significant inhibitory activity for salivary amylase. Use of S. calva root extract will provide a wider protection against different pathogenic oral microflora. Use of this extract singly or in combination is strongly recommended in the dentifrice formulations.

  14. Continued root development of a surgically repositioned human incisor tooth germ.

    Science.gov (United States)

    Kim, Seunghye; Kim, Junhewk; Song, Je Seon; Choi, Hyung-Jun; Choi, Byung-Jai; Kim, Seong-Oh

    2013-05-01

    Conventional orthodontic traction may not be the treatment of choice in cases of inverted impaction of a maxillary incisor, especially when located near the alveolar crest. Poor prognosis is associated with the limited space for proper root development, resulting in a root too short for normal function and/or a severely dilacerated root interrupting the force-induced positioning. The surgical repositioning of ectopic impacted toothgerm before the development of root could be a valuable alternative choice of treatment before the decision of extraction. In this case report, an impacted immature incisor toothgerm in complete inversion was surgically repositioned using a closed-flap technique in a boy who was 6 years 8 months old. Continued root formation and spontaneous eruption were observed after surgery over the 51-month follow-up period, without pulpal or periodontal complications. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. The skin-depigmenting potential of Paeonia lactiflora root extract and paeoniflorin: in vitro evaluation using reconstructed pigmented human epidermis.

    Science.gov (United States)

    Qiu, J; Chen, M; Liu, J; Huang, X; Chen, J; Zhou, L; Ma, J; Sextius, P; Pena, A-M; Cai, Z; Jeulin, S

    2016-10-01

    The roots of the herb Paeonia lactiflora ('White Peony') are used in association with other herbs in traditional clinical cosmetic practice in China as oral treatment for skin pigmentary disorders, such as brown or dark pigmentary spots. However, the skin-depigmenting potential of Paeonia lactiflora root extract and its main ingredient paeoniflorin has been scarcely investigated by topical application. The purpose of this study was to evaluate the efficacy of Paeonia lactiflora root extract and paeoniflorin as skin whitening agent in cosmetic application. Paeonia lactiflora root extract (containing 53.25% of paeoniflorin) and paeoniflorin (97% purity) were applied topically on reconstructed pigmented human epidermis model, a three-dimensional (3D) human skin equivalent, showing morphological and functional characteristics similar to those of in vivo human skin. Two specific methods were used for quantifying melanin inside the reconstructed pigmented epidermis: Fontana-Masson staining (2D quantification) and multiphoton microscopy (3D quantification). Compared to vehicle (dimethyl sulfoxide DMSO), a significant decrease in 2D and 3D melanin content was observed after topical application on reconstructed pigmented epidermis of Paeonia lactiflora extract at 300 μg mL(-1) (-28% and -27%, respectively) and paeoniflorin at 120 μg mL(-1) /250 μM (-30% and -23%, respectively), which is in the same order of magnitude as the positive reference 4-n-butylresorcinol at 83 μg mL(-1) /500 μM (-26% and -40%, respectively). These results demonstrate, for the first time, the depigmenting potential of paeoniflorin and thus the potential interest of using Paeonia lactiflora root extracts containing paeoniflorin in cosmetic or dermatological applications for reducing the severity of some hyperpigmented skin disorders. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  16. Evaluation of cytotoxicity and up-regulation of gelatinases in human fibroblast cells by four root canal sealers.

    Science.gov (United States)

    Silva, E J N L; Accorsi-Mendonça, T; Almeida, J F A; Ferraz, C C R; Gomes, B P F A; Zaia, A A

    2012-01-01

      To investigate the effects of root canal sealers on the cytotoxicity and gelatinolytic activity of matrix metalloproteinases (MMPs) in human fibroblasts.   Human fibroblasts (MRC5, 3×10(5) cells per well) were incubated directly or indirectly with AH Plus, Endomethasone N, Pulp Canal Sealer EWT or Sealapex for 30 min, 1, 4 or 24 h (time-points). The cytotoxicity of all root canal sealers was determined by counting viable cells using the trypan blue exclusion assay. Supernatants of cell cultures incubated with root sealers directly or indirectly were collected after each time-point to determine the levels of MMP-2 and MMP-9 gelatinolytic activity by gelatin zymography. Data were analysed using anova and the Tukey's tests.   Cells secreted MMP-2 after periods of 4 and 24 h; however, there were no significant differences between the sealers. Secretion of gelatinases was elevated by root canal sealers in direct contact with the cell monolayer when compared to indirect contact (P MRC5 fibroblasts. AH Plus had the highest cytotoxicity amongst the tested sealers, but all were associated with cytotoxic effects. © 2011 International Endodontic Journal.

  17. Keyhole interlaminar dorsal rhizotomy for spastic diplegia in cerebral palsy.

    Science.gov (United States)

    Sindou, Marc; Georgoulis, George

    2015-07-01

    The efficiency and safety of dorsal rhizotomies for cerebral palsy lie in the accuracy of radicular identification together with selectivity of root sectioning. Two different exposures are currently in use. The first is extended laminotomy/laminectomy from the upper lumbar level to the sacrum, which allows accurate identification of all L2-S2 roots/rootlets. The second is limited laminotomy exposing the conus/cauda equina at the thoracolumbar junction; this less invasive method limits accessibility to the roots. To optimize the accuracy and selectivity while minimizing invasiveness, the authors developed a tailored interlaminar procedure targeting the radicular levels involved in the harmful components of spasticity directly and individually. Six patients with spastic diplegia at different levels of the Gross Motor Functional Classification System were selected. In each patient, two to three interlaminar spaces, preselected according to planning, were enlarged in the "keyhole" fashion, respecting the spinous processes and interspinous ligaments. Ventral root stimulation identified the radicular level. Dorsal root stimulation evaluated its implication in the hyperactive segmental circuits, helping quantify the percentage of rootlets to be cut. There were neither wound-related nor general complications. At 1 year of follow-up, X-ray examination did not reveal kyphosis or instability. In all children, the excess of spasticity was reduced. The Ashworth score decreased from 3.2 on average to 0.6 postoperatively (range: 2-4 to 0-2). Regarding the functional status at 1 year of follow-up for the three ambulatory children, the Gillette ability-to-walk score increased from 3/10 on average to 7.3/10 postoperatively (range: 2-4 to 7-8). For the three non-ambulatory children, abnormal postures, painful contractures and ease of care were much improved. Keyhole interlaminar dorsal rhizotomy (KIDr) offers direct intradural access to each of the ventral/dorsal roots, thus

  18. Extensive description and comparison of human supra-gingival microbiome in root caries and health.

    Directory of Open Access Journals (Sweden)

    Lin Chen

    Full Text Available Knowledge of the polymicrobial etiology of root caries is limited. To conduct a comprehensive research study on root caries, we utilized 454-pyrosequencing of 16S rRNA gene libraries and quantitative PCR to compare supra-gingival bacterial communities from healthy sites and carious sites of 21 patients with root caries (Patient-controls and Patient-cases and the sites of 21 healthy individuals (Healthy-controls from two nursing homes. Healthy-controls and Patient-cases showed no significant differences in terms of biomass, species richness, and species diversity. However, as for beta diversity based on either community membership metric (unweighted UniFrac or community structure metric (weighted UniFrac, Healthy-controls and Patient-cases were clearly distinguished from each other, appearing more variable in the community membership and structure in root caries microbiome but relatively conserved in the health microbiome. The Patient-controls group was at an intermediate stage between Healthy-controls and Patient-cases, but was more inclined to the former. Demonstrated in both relative abundance and prevalence of species in health and root caries, Propionibacterium acidifaciens, Streptococcus mutans, Olsenella profusa, Prevotella multisaccharivorax, and Lactobacillus crispatus were found to be most associated with root caries, whereas Delftia acidovorans, Bacteroidetes[G-2] sp., Lachnospiraceae[G-3] sp., and Prevotella intermedia are most associated with health. Our study provides a basis for further elucidating the microbial etiology of root caries in the elderly.

  19. In Vitro Cytotoxicity of a New Nano Root Canal Sealer on Human Gingival Fibroblasts

    Science.gov (United States)

    Javidi, Maryam; Dastmalchi, Parisa; Zarei, Mina; Shayani Rad, Maryam; Ghorbani, Ahmad

    2017-01-01

    Introduction: The aim of this in vitro study was to evaluate the cytotoxicity of a new nano zinc-oxide eugenol (NZOE) sealer on human gingival fibroblasts (HGFs) compared with Pulpdent (micro-sized ZOE sealer) and AH-26 (resin-based sealer). Methods and Materials: The Pulpdent, AH-26, and NZOE sealers were prepared and exposed to cell culture media immediately after setting, and 24 h and one week after setting. Then, the primary cultured HGFs were incubated for 24 h with different dilutions (1:1 to 1:32) of each sealer extract. Cell viability was evaluated by methyl thiazolyl diphenyl tetrazolium bromide (MTT) assay. The results were compared using two-way analysis of variance followed by Tukey’s post hoc test. The level of significance was set at 0.05. Results: All sealer extracts, up to 32 times dilutions, showed cytotoxicity when exposed to HGF immediately after setting. The extracts obtained 24 h or one week after setting showed lower cytotoxicity than extracts obtained immediately after setting. At all setting times, NZOE showed lower cytotoxicity than Pulpdent and AH-26. While one-week extracts of NZOE had no significant effect on the viability of HGF at dilutions 1:4 to 1:32, both Pulpdent and AH-26 decreased the cell viability at dilutions of 1:4 and 1:8. Conclusion: NZOE exhibited lower cytotoxicity compared to Pulpdent and AH-26 on HGF and has the potential to be considered as a new root canal filling material. PMID:28512490

  20. Standardized Sophora pachycarpa Root Extract Enhances Osteogenic Differentiation in Adipose-derived Human Mesenchymal Stem Cells.

    Science.gov (United States)

    Mollazadeh, Samaneh; Neshati, Vajiheh; Fazly Bazzaz, Bibi Sedigheh; Iranshahi, Mehrdad; Mojarrad, Majid; Naderi-Meshkin, Hojjat; Kerachian, Mohammad Amin

    2017-05-01

    Bone defect is an important topic in public health. Novel therapies are based on osteogenic induction by natural antiosteoporotic compounds including plant-derived estrogens. In the current study, the osteogenic potential of Sophora pachycarpa root extract (SPRE) was explored on human adipose-derived mesenchymal stem cells. Herein, adipose-derived mesenchymal stem cells were osteoinducted in the presence of increased concentrations of the extract for 21 days. Then, cell viability was evaluated by MTT assay, and the differentiated cells were stained by Alizarin Red S for calcium deposition and subjected to alkaline phosphatase (ALP) assay for enzymatic activity. To assess the expression of bone-related genes, treated cells were evaluated by real-time polymerase chain reaction. The MTT test demonstrated that SPRE had no toxic effects on the cell viability. Treating the cells with SPRE noticeably promoted ALP activity, mineralization, and mRNA expression of runt-related transcription factor 2 (RUNX2), bone gamma-carboxyglutamate protein (BGLAP), secreted phosphoprotein 1 (SPP1), and collagen type I alpha 1 (COL1A1). Additionally, cells subjected to 0.1 μg/mL SPRE showed the highest osteogenic effects. According to high-performance liquid chromatography fingerprinting of SPRE, the osteoprotective effects of SPRE is probably due to presence of phytochemicals with estrogen-like activity in the extract. Thus, SPRE might be a suitable therapeutic agent for bone defects therapy in the future research. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Human impacts on soil carbon dynamics of deep-rooted Amazonian forests

    Science.gov (United States)

    Nepstad, Daniel C.; Stone, Thomas A.; Davidson, Eric A.

    1994-01-01

    Deforestation and logging degrade more forest in eastern and southern Amazonia than in any other region of the world. This forest alteration affects regional hydrology and the global carbon cycle, but our current understanding of these effects is limited by incomplete knowledge of tropical forest ecosystems. It is widely agreed that roots are concentrated near the soil surface in moist tropical forests, but this generalization incorrectly implies that deep roots are unimportant in water and C budgets. Our results indicate that half of the closed-canopy forests of Brazilian Amazonic occur where rainfall is highly seasonal, and these forests rely on deeply penetrating roots to extract soil water. Pasture vegetation extracts less water from deep soil than the forest it replaces, thus increasing rates of drainage and decreasing rates of evapotranspiration. Deep roots are also a source of modern carbon deep in the soil. The soils of the eastern Amazon contain more carbon below 1 m depth than is present in above-ground biomass. As much as 25 percent of this deep soil C could have annual to decadal turnover times and may be lost to the atmosphere following deforestation. We compared the importance of deep roots in a mature, evergreen forest with an adjacent man-made pasture, the most common type of vegetation on deforested land in Amazonia. The study site is near the town of Paragominas, in the Brazilian state of Para, with a seasonal rainfall pattern and deeply-weathered, kaolinitic soils that are typical for large portions of Amazonia. Root distribution, soil water extraction, and soil carbon dynamics were studied using deep auger holes and shafts in each ecosystem, and the phenology and water status of the leaf canopies were measured. We estimated the geographical distribution of deeply-rooting forests using satellite imagery, rainfall data, and field measurements.

  2. Central projections of primary sensory afferents to the spinal dorsal horn in the long-tailed stingray, Himantura fai.

    Science.gov (United States)

    Kitchener, Peter D; Fuller, Jack; Snow, Peter J

    2010-01-01

    The central projections of primary sensory afferents innervating the caudal region of the pectoral fin of the long-tailed stingray (Himantura fai) were labeled by applying the lipophilic carbocyanine dye DiI to the dorsal roots in fixed tissue. These observations were complemented by examination of hemotoxylin and eosin-stained paraffin sections of the dorsal root entry zone, and transmission electron microscopy of the dorsal horn. Transverse sections of the sensory nerve and dorsal root revealed two distinct myelinated axon sizes in the sensory nerve. Although the thick and thin axons do not appear to group together in the sensory nerves and dorsal root, they segregate into a dorsally directed bundle of thin fibers and a more horizontally directed bundle of thick fibers soon after entering the spinal cord. In DiI-labeled horizontal sections, fibers were observed to enter the spinal cord and diverge into rostrally and caudally directed trajectories. Branching varicose axons could be traced in the dorsal horn gray matter in the segment of entry and about half of the adjacent rostral and caudal segments. In transverse and sagittal sections, DiI-labeled afferents were seen to innervate the superficial and, to a lesser extent, deeper laminae of the dorsal horn, but not the ventral horn. Electron microscopy of unlabeled dorsal horn sections revealed a variety of synaptic morphologies including large presynaptic elements (some containing dense-core vesicles) making synaptic contacts with multiple processes in a glomerular arrangement; in this respect, the synaptic ultrastructure is broadly similar to that seen in the dorsal horn of rodents and other mammals. Copyright © 2010 S. Karger AG, Basel.

  3. Fracture resistance of weakened human premolar roots after use of a glass fiber post together with accessory posts

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    Clarissa Estefani SEGATO

    Full Text Available OBJECTIVE: To evaluate the fracture strength of human premolar teeth with wide root canals, restored with glass fiber posts and resin cement, together with different numbers of accessory posts.MATERIAL AND METHOD: Thirty-six premolars received standardized preparations that simulated weakened roots, and were divided into three groups (n=12: G0 - glass fiber post (Reforpost/Angelus cementation with dual cure resin cement (Rely X ARC/3M ESPE; G1 - glass fiber post cementation and one accessory post (Reforpin/Angelus, with dual cure resin cement; G2 - glass fiber post cementation and two accessory posts, with dual cure resin cement. Resin composite cores were placed in each tooth. A metal coping was placed in a standardized position on the cores to perform the compressive tests using a test machine. Testing was performed applying a force parallel to the long axis of the teeth at a speed of 0.5 mm/min. Fracture mode was analyzed under a stereoscopic loupe, classified by scores.RESULT: the Analysis of Variance (ANOVA was applied, and there was no statistical difference in the mean values of fracture strength among the groups (in kgf: G0 = 91.1 ± 56.9; G1 = 104.7 ± 66.6; G2 = 106.1 ± 51.9. Greater frequency of fracture or cracks was observed in the cervical one-third of the root in the teeth without cemented accessory posts, but no statistical difference was observed among the fracture modes.CONCLUSION: The number of accessory posts cemented into debilitated roots had no influence on either fracture strength or type of fracture of pre-molar roots.

  4. The function of the long dorsal sacroiliac ligament : its implications for understanding low back pain

    NARCIS (Netherlands)

    Pool-Goudzwaard, A.L.; Vleeming, A; Hammudoghlu, D; Stoeckart, R.; Snijders, C.; Mens, Jan M A

    1996-01-01

    STUDY DESIGN: In embalmed human bodies the tension of the long dorsal sacroiliac ligament was measured during incremental loading of anatomical structures that are biomechanically relevant. OBJECTIVES: To assess the function of the long dorsal sacroiliac ligament. SUMMARY OF BACKGROUND DATA: In many

  5. Role of the Dorsal Hippocampus in Object Memory Load

    Science.gov (United States)

    Sannino, Sara; Russo, Fabio; Torromino, Giulia; Pendolino, Valentina; Calabresi, Paolo; De Leonibus, Elvira

    2012-01-01

    The dorsal hippocampus is crucial for mammalian spatial memory, but its exact role in item memory is still hotly debated. Recent evidence in humans suggested that the hippocampus might be selectively involved in item short-term memory to deal with an increasing memory load. In this study, we sought to test this hypothesis. To this aim we developed…

  6. Root-associated fungi of Vaccinium carlesii in subtropical forests of China: intra- and inter-annual variability and impacts of human disturbances.

    Science.gov (United States)

    Zhang, Yanhua; Ni, Jian; Tang, Fangping; Pei, Kequan; Luo, Yiqi; Jiang, Lifen; Sun, Lifu; Liang, Yu

    2016-03-01

    Ericoid mycorrhiza (ERM) are expected to facilitate establishment of ericaceous plants in harsh habitats. However, diversity and driving factors of the root-associated fungi of ericaceous plants are poorly understood. In this study, hair-root samples of Vaccinium carlesii were taken from four forest types: old growth forests (OGF), secondary forests with once or twice cutting (SEC I and SEC II), and Cunninghamia lanceolata plantation (PLF). Fungal communities were determined using high-throughput sequencing, and impacts of human disturbances and the intra- and inter-annual variability of root-associated fungal community were evaluated. Diverse fungal taxa were observed and our results showed that (1) Intra- and inter-annual changes in root-associated fungal community were found, and the Basidiomycota to Ascomycota ratio was related to mean temperature of the sampling month; (2) Human disturbances significantly affected structure of root-associated fungal community of V. carlesii, and two secondary forest types were similar in root-associated fungal community and were closer to that of the old growth forest; (3) Plant community composition, edaphic parameters, and geographic factors significantly affected root-associated fungal communities of V. carlesii. These results may be helpful in better understanding the maintenance mechanisms of fungal diversity associated with hair roots of ERM plants under human disturbances.

  7. Structure, chemical composition and mechanical properties of human and rat cementum and its interface with root dentin

    Science.gov (United States)

    Ho, Sunita P.; Yu, Bo; Yun, Wenbing; Marshall, Grayson W.; Ryder, Mark I.; Marshall, Sally J.

    2009-01-01

    This work seeks to establish comparisons of the physical properties of rat and human cementum, root dentin and their interface, including the cementum–dentin junction (CDJ), as a basis for future studies of the entire periodontal complex using rats as animal models. In this study the structure, site-specific chemical composition and mechanical properties of cementum and its interface with root dentin taken from 9- to 12-month-old rats were compared to the physiologically equivalent 40- to 55-year-old human age group using qualitative and quantitative characterization techniques, including histology, atomic force microscopy (AFM), micro-X-ray computed tomography, Raman microspectroscopy and AFM-based nanoindentation. Based on results from this study, cementum taken from the apical third of the respective species can be represented as a woven fabric with radially and circumferentially oriented collagen fibers. In both species the attachment of cementum to root dentin is defined by a stiffness-graded interface (CDJ/cementum–dentin interface). However, it was concluded that cementum and the cementum–dentin interface from a 9- to 12-month-old rat could be more mineralized, resulting in noticeably decreased collagen fiber hydration and significantly higher modulus values under wet conditions for cementum and CDJ (Erat-cementum = 12.7 ± 2.62 GPa; Erat-CDJ = 11.6 ± 3.20 GPa) compared to a 40- to 55-year-old human (Ehuman-cementum = 3.73 ± 1.81 GPa; Ehuman-CDJ = 1.5 ± 0.71 GPa). The resulting data illustrated that the extensions of observations made from animal models to humans should be justified with substantial and equivalent comparison of data across age ranges (life spans) of mammalian species. PMID:18829402

  8. Reliability of plant root comet assay in comparison with human leukocyte comet assay for assessment environmental genotoxic agents.

    Science.gov (United States)

    Reis, Gabriela Barreto Dos; Andrade-Vieira, Larissa Fonseca; Moraes, Isabella de Campos; César, Pedro Henrique Souza; Marcussi, Silvana; Davide, Lisete Chamma

    2017-08-01

    Comet assay is an efficient test to detect genotoxic compounds based on observation of DNA damage. The aim of this work was to compare the results obtained from the comet assay in two different type of cells extracted from the root tips from Lactuca sativa L. and human blood. For this, Spent Pot Liner (SPL), and its components (aluminum and fluoride) were applied as toxic agents. SPL is a solid waste generated in industry from the aluminum mining and processing with known toxicity. Three concentrations of all tested solutions were applied and the damages observed were compared to negative and positive controls. It was observed an increase in the frequency of DNA damage for human leukocytes and plant cells, in all treatments. On human leukocytes, SPL induced the highest percentage of damage, with an average of 87.68%. For root tips cells of L. sativa the highest percentage of damage was detected for aluminum (93.89%). Considering the arbitrary units (AU), the average of nuclei with high levels of DNA fragmentation was significant for both cells type evaluated. The tested cells demonstrated equal effectiveness for detection of the genotoxicity induced by the SPL and its chemical components, aluminum and fluoride. Further, using a unique method, the comet assay, we proved that cells from root tips of Lactuca sativa represent a reliable model to detect DNA damage induced by genotoxic pollutants is in agreement of those observed in human leukocytes as model. So far, plant cells may be suggested as important system to assess the toxicological risk of environmental agents. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Effects of enamel matrix proteins on tissue formation along the roots of human teeth.

    NARCIS (Netherlands)

    Bosshardt, D.D.; Sculean, A.; Windisch, P.; Pjetursson, B.E.; Lang, N.P.

    2005-01-01

    OBJECTIVE: Enamel matrix-derived proteins (EMD) are thought to trigger the formation of acellular extrinsic fibre cementum (AEFC), while other reports indicate that EMD may have osteogenic potential. The aim of the present study was to characterize the tissues developing on the root surface

  10. Influence of Different Apical Preparations on Root Canal Cleanliness in Human Molars: a SEM Study

    Directory of Open Access Journals (Sweden)

    Gianluca Plotino

    2014-07-01

    Full Text Available Objectives: To compare the influence of type and dimensions of the apical preparation on the cleanliness of the apical area in molars. Material and Methods: A total of 120 root canals (MB and DB root canals from 30 maxillary molars and mesial root canals from 30 mandibular molars were instrumented with Mtwo NiTi rotary instruments to a size 25/0.06 taper and were equally divided into three different experimental groups depending on the subsequently apical root canal preparation: Group 1: no further apical preparation, Group 2: apical preparation with Mtwo files to a size 40/0.04 taper, Group 3: apical preparation with Mtwo Apical Files. All root canals were observed through scanning electron microscopy (SEM. Presence of superficial debris and smear layer was evaluated using a score system. Data were statistically analysed using the Kruskal-Wallis and Bonferroni tests with a level of significance set at P 0.05, while at the apical level, there was a significant difference for both residual debris and presence of smear layer between Group 1 and both Group 2 (P = 0.003 and P = 0.014 and 3 (P = 0.012 and P = 0.021, while no difference was present between Group 2 and Group 3 (P = 0.871 and P = 0.923. Conclusions: Cleanliness of the apical third in terms of debris and smear layer was statistically better when an apical preparation was performed to a size 40/0.04 taper or with the use of the Mtwo Apical Files.

  11. In vivo Quantification of the Effects of Radiation and Presence of Hair Follicle Pores on the Proliferation of Fibroblasts in an Acellular Human Dermis in a Dorsal Skinfold Chamber: Relevance for Tissue Reconstruction following Neoadjuvant Therapy.

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    Mario Vitacolonna

    Full Text Available In neoadjuvant therapy, irradiation has a deleterious effect on neoangiogenesis. The aim of this study was to examine the post-implantation effects of neoadjuvant irradiation on the survival and proliferation of autologous cells seeded onto an acellular human dermis (hAD; Epiflex. Additionally, we examined the influence of dermal hair follicle pores on viability and proliferation. We used dorsal skinfold chambers implanted in rats and in-situ microscopy to quantify cell numbers over 9 days.24 rats received a skinfold chamber and were divided into 2 main groups; irradiated and unirradiated. In the irradiated groups 20Gy were applied epicutaneously at the dorsum. Epiflex pieces were cut to size 5x5mm such that each piece had either one or more visible hair follicle pores, or no such visible pores. Fibroblasts were transduced lentiviral with a fluorescent protein for cell tracking. Matrices were seeded statically with 2.5x104 fluorescent fibroblasts and implanted into the chambers. In each of the two main groups, half of the rats received Epiflex with hair follicle pores and half received Epiflex without pores. Scaffolds were examined in-situ at 0, 3, 6 and 9 days after transplantation. Visible cells on the surface were quantified using ImageJ.In all groups cell numbers were decreased on day 3. A treatment-dependent increase in cell numbers was observed at subsequent time points. Irradiation had an adverse effect on cell survival and proliferation. The number of cells detected in both irradiated and non-irradiated subjects was increased in those subjects that received transplants with hair follicle pores.This in-vivo study confirms that radiation negatively affects the survival and proliferation of fibroblasts seeded onto a human dermis transplant. The presence of hair follicle pores in the dermis transplants is shown to have a positive effect on cell survival and proliferation even in irradiated subjects.

  12. In vivo Quantification of the Effects of Radiation and Presence of Hair Follicle Pores on the Proliferation of Fibroblasts in an Acellular Human Dermis in a Dorsal Skinfold Chamber: Relevance for Tissue Reconstruction following Neoadjuvant Therapy.

    Science.gov (United States)

    Vitacolonna, Mario; Belharazem, Djeda; Maier, Patrick; Hohenberger, Peter; Roessner, Eric Dominic

    2015-01-01

    In neoadjuvant therapy, irradiation has a deleterious effect on neoangiogenesis. The aim of this study was to examine the post-implantation effects of neoadjuvant irradiation on the survival and proliferation of autologous cells seeded onto an acellular human dermis (hAD; Epiflex). Additionally, we examined the influence of dermal hair follicle pores on viability and proliferation. We used dorsal skinfold chambers implanted in rats and in-situ microscopy to quantify cell numbers over 9 days. 24 rats received a skinfold chamber and were divided into 2 main groups; irradiated and unirradiated. In the irradiated groups 20Gy were applied epicutaneously at the dorsum. Epiflex pieces were cut to size 5x5mm such that each piece had either one or more visible hair follicle pores, or no such visible pores. Fibroblasts were transduced lentiviral with a fluorescent protein for cell tracking. Matrices were seeded statically with 2.5x104 fluorescent fibroblasts and implanted into the chambers. In each of the two main groups, half of the rats received Epiflex with hair follicle pores and half received Epiflex without pores. Scaffolds were examined in-situ at 0, 3, 6 and 9 days after transplantation. Visible cells on the surface were quantified using ImageJ. In all groups cell numbers were decreased on day 3. A treatment-dependent increase in cell numbers was observed at subsequent time points. Irradiation had an adverse effect on cell survival and proliferation. The number of cells detected in both irradiated and non-irradiated subjects was increased in those subjects that received transplants with hair follicle pores. This in-vivo study confirms that radiation negatively affects the survival and proliferation of fibroblasts seeded onto a human dermis transplant. The presence of hair follicle pores in the dermis transplants is shown to have a positive effect on cell survival and proliferation even in irradiated subjects.

  13. Root canal configuration of human permanent mandibular first molars of an indo-dravidian population based in Southern India: An In vitro study

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    J V Karunakaran

    2017-01-01

    Full Text Available Aim: This study aims to analyze root canal configuration of human permanent mandibular first molars of an indo-Dravidian population based in southern India. Materials and Methods: A total of 1147 mandibular first permanent molars were collected, cleansed, and stored. The number of roots was recorded, access preparations made, pattern of orifices recorded after pulpal floor debridement, dye injected into the canals using apical negative pressure and subjected to a clearing technique. They were then analyzed using a stereo microscope and the canal configurations recorded (Vertucci. The number of roots, the pattern of orifices and canal configuration were recorded. Results: The pattern of orifices was triangular (87.9%, rectangular (8.5%, C-shaped (3.0%, and two orifice pattern (0.6%. About 95.6% of teeth had two roots, and 4.4% had three roots. The most common canal system configuration in mesial root was Vertucci type IV (52.3%, followed by type II (35%. Root canal configuration of the distal root revealed type I configuration in 62.7%, followed by types II (14.5% and IV (12.4%. The distolingual root had a type I configuration. Conclusion: Awareness of canal configuration, adequate clinical skills, use of specialized techniques of diagnosis, debridement and obturation will pave the way for successful treatment outcomes.

  14. Ag-loaded mesoporous bioactive glasses against Enterococcus faecalis biofilm in root canal of human teeth.

    Science.gov (United States)

    Fan, Wei; Wu, Daming; Ma, Tengjiao; Fan, Bing

    2015-01-01

    Ag-loaded mesoporous bioactive glass (Ag-MBG) powders were synthesized and characterized. The ions release of Ag-MBGs in Tris-HCl and the pH stability of simulated body fluids after immersing Ag-MBGs were tested. Root canals were inoculated with Enterococcus faecalis for 4 weeks, and the antibacterial activity of MBGs, Ag-MBGs and calcium hydroxide against E. faecalis biofilm were evaluated. Results showed that Ag-MBGs possessed highly ordered mesoporous structure with silver nanoparticles deposited in the mesopores, which enabled a sustained Ag ions released. The biofilms treated with Ag-MBGs showed a significant structural disruption compared with MBGs. These results indicated that Ag-MBGs possess a potent antibacterial effect against E.faecalis biofilm in root canal, and the antibacterial activity was induced by the release of Ag ions from Ag-MBGs.

  15. Smoking may affect root coverage outcome: a prospective clinical study in humans.

    Science.gov (United States)

    Martins, Angela Guimarães; Andia, Denise Carleto; Sallum, Antonio Wilson; Sallum, Enilson A; Casati, Márcio Z; Nociti Júnior, Francisco H

    2004-04-01

    Cigarette smoking has been shown to negatively influence healing following periodontal therapeutic procedures. Therefore, the aim of this study was to evaluate the impact of smoking on clinical outcome of root coverage following subepithelial connective tissue graft (CTG) surgery. Eighteen defects were treated in 15 patients (seven smokers and eight non-smokers) who presented canine and pre-molar Miller Class I and II recessions. CTG was performed and clinical measurements were obtained at baseline, and 30, 60, 90, and 120 days after surgery. Clinical measurements included plaque and gingival indexes, gingival recession, probing depth, clinical attachment level, gingival thickness, and keratinized tissue width. Intragroup analysis showed that CTG was able to promote root coverage, increase gingival thickness, and improve clinical attachment level in both groups (P tissue compared to non-smokers (3.30 +/- 0.86 mm versus 4.50 +/- 1.16 mm) (P periodontal plastic therapy.

  16. Human Histologic Repair and Regeneration After Biologic Preparation of Diseased Root Surfaces,

    Science.gov (United States)

    1983-12-01

    29: 98, 1958. 6. Ramfjord, S. P.: "Long Term Longitudinal Studies of Various Periodontal Therapies." Midwest Society of Periodontology 24th Annual...study. J Periodontol 51: 652, 1980. 12. Gottsegen, R.: "Update -- Where Are We Now?" Midwest Society of Periodontology 24th Annual Meeting. February 14...and 15, 1981. 13. Morris, M.: "Chemical Therapies of the Diseased Root." Midwest Society of Periodontology 24th Annual Meeting. February 14 and 15

  17. Inhibition of Human Cervical Cancer Cell Growth by Ethanolic Extract of Boerhaavia diffusa Linn. (Punarnava Root

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    Rakhi Srivastava

    2011-01-01

    Full Text Available In Indian traditional medicine, Boerhaavia diffusa (punarnava roots have been widely used for the treatment of dyspepsia, jaundice, enlargement of spleen, abdominal pain and as an anti-stress agent. Pharmacological evaluation of the crude ethanolic extract of B. diffusa roots has been shown to possess antiproliferative and immunomodulatory properties. The extract of B. diffusa was studied for anti-proliferative effects on the growth of HeLa cells and for its effect on cell cycle. Bio-assays of extracts from B. diffusa root showed that a methanol : chloroform fraction (BDF 5 had an antiproliferative effect on HeLa cells. After 48 h of exposure, this fraction at a concentration of 200 μg mL−1 significantly reduced cell proliferation with visible morphological changes in HeLa cells. Cell cycle analysis suggests that antiproliferative effect of BDF 5 could be due to inhibition of DNA synthesis in S-phase of cell cycle in HeLa cells, whereas no significant change in cell cycle was detected in control cells. The fraction BDF 5 caused cell death via apoptosis as evident from DNA fragmentation and caspase-9 activation. Thus the extract has potential to be evaluated in detail to assess the molecular mechanism-mediated anticancer activities of this plant.

  18. A afferent fibers are involved in the pathology of central changes in the spinal dorsal horn associated with myofascial trigger spots in rats.

    Science.gov (United States)

    Meng, Fei; Ge, Hong-You; Wang, Yong-Hui; Yue, Shou-Wei

    2015-11-01

    A afferent fibers have been reported to participate in the development of the central sensitization induced by inflammation and injuries. Current evidence suggests that myofascial trigger points (MTrPs) induce central sensitization in the related spinal dorsal horn, and clinical studies indicate that A fibers are associated with pain behavior. Because most of these clinical studies applied behavioral indexes, objective evidence is needed. Additionally, MTrP-related neurons in dorsal root ganglia and the spinal ventral horn have been reported to be smaller than normal, and these neurons were considered to be related to A fibers. To confirm the role of A fibers in MTrP-related central changes in the spinal dorsal horn, we studied central sensitization as well as the size of neurons associated with myofascial trigger spots (MTrSs, equivalent to MTrPs in humans) in the biceps femoris muscle of rats and provided some objective morphological evidence. Cholera toxin B subunit-conjugated horseradish peroxidase was applied to label the MTrS-related neurons, and tetrodotoxin was used to block A fibers specifically. The results showed that in the spinal dorsal horn associated with MTrS, the expression of glutamate receptor (mGluR1α/mGluR5/NMDAR1) increased, while the mean size of MTrS-related neurons was smaller than normal. After blocking A fibers, these changes reversed to some extent. Therefore, we concluded that A fibers participated in the development and maintenance of the central sensitization induced by MTrPs and were related to the mean size of neurons associated with MTrPs in the spinal dorsal horn.

  19. Changes in the expression of NaV1.7, NaV1.8 and NaV1.9 in a distinct population of dorsal root ganglia innervating the rat knee joint in a model of chronic inflammatory joint pain.

    Science.gov (United States)

    Strickland, Iain T; Martindale, Jo C; Woodhams, Peter L; Reeve, Alison J; Chessell, Iain P; McQueen, Daniel S

    2008-07-01

    Voltage-gated sodium channels play an essential role in regulating the excitability of nociceptive primary afferent neurones. In particular the tetrodotoxin-sensitive (TTX-S) Na(V)1.7 and the tetrodotoxin-resistant (TTX-R) Na(V)1.8 and Na(V)1.9 channels have been suggested to play a role in inflammatory pain. Previous work has revealed acute administration of inflammatory mediators, such as Freund's complete adjuvant (FCA) or carrageenan caused an upregulation in the levels of Na(V)1.7 and Na(V)1.8 protein in DRG (dorsal root ganglia) tissue up to 4 days post-insult. In the present study, the expression of Na(V)1.7, Na(V)1.8 and Na(V)1.9 was examined over a 28 day timecourse during a rat model of FCA-induced chronic inflammatory joint pain. Using the retrograde tracer Fast Blue (FB) and specific Na(V)1.7, Na(V)1.8 and Na(V)1.9 sodium channel antibodies, immunohistochemical staining techniques were used to study sodium channel expression in a distinct population of L3-L5 knee joint afferent DRGs. In the ganglia, counts were made of positively labelled cells in the FB population. The results demonstrate that, following FCA injection, Na(V)1.9 expression is upregulated at days 14, 21 and 28 post-FCA, with Na(V)1.7 and Na(V)1.8 showing increased channel expression at days 14 and 28. These observations are accompanied by a unilateral joint hypersensitivity in the FCA-injected knee indicated by a behavioural shift in weight distribution measured using an incapacitance tester. The increased presence of these channels suggests that Na(V)1.7, Na(V)1.8 and Na(V)1.9 play a role, at least in part, in the maintenance of chronic inflammatory pain several weeks after the initial insult.

  20. [The dorsal nerve of the clitoris: surgical applications].

    Science.gov (United States)

    Balaya, V; Aubin, A; Rogez, J-M; Douard, R; Delmas, V

    2014-03-01

    To describe the course of the dorsal nerve of the clitoris (DNC) to better define its anatomy in the human adult and to help surgeons to avoid iatrogenic injury during surgical procedures. An extensive review of the current literature was done on Medline via PubMed by using the following keywords: "anatomie du clitoris", "anatomy of clitoris", "nerf dorsal du clitoris", "dorsal nerve of clitoris", "réparation clitoridienne", "transposition clitoridienne", "surgery of the clitoris", "clitoridoplasty". This review analyzed dissection, magnetic resonance imaging, 3-dimensional sectional anatomy reconstruction and immuno-histochemical studies. The DNC comes from the pudendal nerve. He travels from under the inferior pubis ramus to the posterosuperior edge of the clitoral crus. The DNC reappears under the pubic symphysis and enters the deep component of the suspensory ligament. He runs on the dorsal face of the clitoral body at 11 and 1 o'clock. Distally, he gives many nervous ramifications, runs along the tunica and enters the glans. The NDC might be surgically injured (i) under the pubic symphysis, at the union of the two crus of clitoris and (ii) on the dorsal surface of the clitoral body. The pathway of the DNC on the dorsal face of the clitoris permits to approach the ventral face of the clitoris without risk of iatrogenic injuries. The distance between the pubic symphysis and the DNC implies that the incision should be done just under the pubic symphysis. Distally, the dissection of the DNC next the glands appears as dangerous and impossible, considering that the DNC is too close to the glandular tissues. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  1. Evaluation of root canal morphology of human primary molars by using CBCT and comprehensive review of the literature.

    Science.gov (United States)

    Ozcan, Gozde; Sekerci, Ahmet Ercan; Cantekin, Kenan; Aydinbelge, Mustafa; Dogan, Salih

    2016-01-01

    Knowledge of primary tooth morphology is essential for clinical dentistry, especially for root canal treatment and dental traumatology. However, this has not been well documented to date with a large sample. This study was carried out to investigate the variation in number and morphology of the root canals of the primary molars, to study the applicability of cone beam computerized tomography (CBCT) in assessing the same and to provide a comprehensive review of the literature. A total of 343 primary molars, without any root resorption, were divided into four main groups including the maxillary first molars, maxillary second molars, mandibular first molars and mandibular second molars. All of them were analysed in CBCT images in the axial, sagittal and coronal planes. Various parameters such as the number of roots, number of canals, the root canal type, diameter of root and root canal and root canal curvature were studied. Primary molars in all four groups showed variability in the number of roots and root canals. As far as length of the roots was concerned, the palatal root of the maxillary molar was found to be longest, while the distobuccal root was shortest. In mandibular molars, the mesial root was longer than the distal root. The length of distobuccal root canal of the maxillary molars and the distolingual canal of the mandibular molars was found to be shortest. The number of roots and root canals varied from two to four and three to four, respectively. The maxillary molars exhibited more one-canal than two-canal roots. The present study provides comprehensive information to the existing literature concerning the variation in root canal morphology of the maxillary and mandibular primary molar teeth. These data may help clinicians in the root canal treatment of these teeth.

  2. The anticancer potential of steroidal saponin, dioscin, isolated from wild yam (Dioscorea villosa) root extract in invasive human breast cancer cell line MDA-MB-231 in vitro

    Science.gov (United States)

    Previously, we observed that wild yam (Dioscorea villosa) root extract (WYRE) was able to activate GATA3 in human breast cancer cells targeting epigenome. This study aimed to 'nd out if dioscin (DS), a bioactive compound of WYRE, can modulate GATA3 functions and cellular invasion in human breast can...

  3. Liposarcome dorsal: aspect clinique rare

    Science.gov (United States)

    Agbessi, Odry; Arrob, Adil; Fiqhi, Kamal; Khalfi, Lahcen; Nassih, Mohammed; El Khatib, Karim

    2015-01-01

    Décrit la première fois par Virchow en 1860, le liposarcome est une tumeur mésenchymateuse rare. Cette rareté est relative car les liposarcomes représentent quand même 14 à 18% de l'ensemble des tumeurs malignes des parties molles et ils constituent le plus fréquent des sarcomes des parties molles. Pour la majorité des auteurs, il ne se développerait jamais sur un lipome ou une lipomatose préexistant. Nous rapportons un cas de volumineux liposarcome de la face dorsale du tronc. L'histoire de la maladie, l'aspect clinique inhabituel « de tumeur dans tumeur », l'aspect de la pièce opératoire nous fait évoquer la possibilité de la transformation maligne d'un lipome bénin préexistant. PMID:26113914

  4. Maslow's Theory of Human Motivation and its Deep Roots in Individualism : Interrogating Maslow's Applicability in Africa

    NARCIS (Netherlands)

    Mawere, Munyaradzi; Mubaya, Tapuwa R.; van Reisen, Mirjam; Stam, van Gertjan; Mawere, Munyaradzi; Nhemachena, Artwell

    Since the postulation of Abraham Maslow's theory of human motivation, the theory has been celebrated as the determining factor to account for and explain human wants and needs. While the theory has its genealogy from an individualistic society, the United States of America, where it was crafted and

  5. Historical Roots of Information Sciences and the Making of E-Humanities.

    NARCIS (Netherlands)

    van den Heuvel, C.M.J.M.; Bod, Rens; Maat, Jaap; Westeijn, Thijs

    2014-01-01

    Christine Borgman in Scholarship in the Digital Age. Information, Infrastructure and the Internet (2007) distinguishes between data of the natural sciences, social sciences and humanities. This distinction has been used as one of the arguments to explain why scholars in the humanities and social

  6. Regenerative Endodontic Treatment of an Immature Necrotic Molar with Arrested Root Development by Using Recombinant Human Platelet-derived Growth Factor: A Case Report.

    Science.gov (United States)

    Zhujiang, Annie; Kim, Sahng G

    2016-01-01

    Regenerative endodontic treatment has provided a treatment option that aims to allow root maturation. The present report describes the regenerative endodontic treatment of a necrotic, immature molar by using recombinant human platelet-derived growth factor (rhPDGF-BB) and shows the continued root maturation in the tooth with arrested root development. A regenerative endodontic procedure that used a growth factor was performed for a necrotic molar with arrested root formation in a 20-year-old patient. Thorough disinfection by using mechanical instrumentation and copious irrigation of antimicrobial agents as well as intracanal medication with calcium hydroxide was performed throughout the first 2 appointments. At the third appointment, the root canals were irrigated with an antimicrobial solution and 17% EDTA, and bleeding was evoked by passing sterile paper points beyond the apex in each canal. Small pieces of a collagen membrane saturated with rhPDGF-BB solution from GEM 21S were packed into each canal. Mineral trioxide aggregate was placed, and Cavit and composite resin were used to restore the tooth. Complete root maturation and resolution of a periapical radiolucency were observed at the 15-month follow-up. The present report presents a regenerative endodontic procedure that uses rhPDGF-BB for a necrotic molar with arrested root development. The finding of continued root development in the present case suggests that regenerative endodontic treatment may be able to resume the root maturation process in teeth with arrested root formation. Further clinical studies are required to investigate the efficacy of rhPDGF-BB in regenerative endodontic treatment. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. Effect of soluble and insoluble fibers within the in vitro fermentation of chicory root pulp by human gut bacteria.

    Science.gov (United States)

    Ramasamy, Uttara S; Venema, Koen; Schols, Henk A; Gruppen, Harry

    2014-07-16

    The aim of this research was to study the in vitro fermentation of chicory root pulp (CRP) and ensiled CRP (ECRP) using human fecal inoculum. Analysis of carbohydrate levels in fermentation digests showed that 51% of all CRP carbohydrates were utilized after 24 h of fermentation. For ECRP, having the same cell wall polysaccharide composition as CRP, but with solubilization of 4 times more of CRP pectin due to ensiling, the fermentation was quicker than with CRP as 11% more carbohydrates were utilized within the first 12 h. The level of fiber utilization for ECRP after 24 h was increased by 8% compared to CRP. This effect on fiber utilization from ECRP seemed to arise from (i) increased levels of soluble pectin fibers (arabinan, homogalacturonan, and galactan) and (ii) ahypothesized more open structure of the remaining cell walls in ECRP, which was more accessible to degradation than the CRP cell wall network.

  8. Production of a tumour-targeting antibody with a human-compatible glycosylation profile in N. benthamiana hairy root cultures.

    Science.gov (United States)

    Lonoce, Chiara; Salem, Reda; Marusic, Carla; Jutras, Philippe V; Scaloni, Andrea; Salzano, Anna Maria; Lucretti, Sergio; Steinkellner, Herta; Benvenuto, Eugenio; Donini, Marcello

    2016-09-01

    Hairy root (HR) cultures derived from Agrobacterium rhizogenes transformation of plant tissues are an advantageous biotechnological manufacturing platform due to the accumulation of recombinant proteins in an otherwise largely protein free culture medium. In this context, HRs descending from transgenic Nicotiana tabacum plants were successfully used for the production of several functional mAbs with plant-type glycans. Here, we expressed the tumor-targeting monoclonal antibody mAb H10 in HRs obtained either by infecting a transgenic N. tabacum line expressing H10 with A. rhizogenes or a glyco-engineered N. benthamiana line (ΔXTFT) with recombinant A. rhizogenes carrying mAb H10 heavy and light chain cDNAs. Selected HR clones derived from both plants accumulated mAb H10 in the culture medium with similar yields (2-3 mg/L). N-glycosylation profiles of antibodies purified from HR supernatant revealed the presence of plant-typical complex structures for N. tabacum-derived mAb H10 and of GnGn structures lacking xylose and fucose for the ΔXTFT-derived counterpart. Both antibody glyco-formats exhibited comparable antigen binding activities. Collectively, these data demonstrate that the co-infection of ΔXTFT Nicotiana benthamiana with recombinant A. rhizogenes is an efficient procedure for the generation of stable HR cultures expressing the tumor-targeting mAb H10 with a human-compatible glycosylation profile, thus representing an important step towards the exploitation of root cultures for the production of 'next generation' human therapeutic antibodies. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. In vitro evaluation of different dental materials used for the treatment of extensive cervical root defects using human periodontal cells.

    Science.gov (United States)

    Michel, Annemarie; Erber, Ralf; Frese, Cornelia; Gehrig, Holger; Saure, Daniel; Mente, Johannes

    2017-04-01

    Repair materials for extensive cervical root defects may come in direct contact with periodontal tissues. This in vitro study compared the effects of four calcium silicate cements (CSC), one resin-modified glass ionomer cement, and one glass carbomer cement on primary human gingival fibroblasts (HGF), alveolar osteoblasts (HAO), and a human osteoblast cell line (hFOB 1.19). HGF, HAO, and hFOB were seeded on discoid test specimens. Relative numbers of viable cells were quantitatively assessed after 1 and 24 h for cytotoxicity/adhesion assays and after 4, 24, 48, and 72 h for proliferation assays. Data were statistically analyzed using non-parametric tests (α = 0.05). Relative to the control (100 %), CSC allowed for mean numbers of 71-81 % viable HGF and 80-82 % viable HAO. Then, 64 % of HGF and 56 % of HAO were assessed on GC Fuji II LC. Mean numbers of viable cells were 59-64 % HGF and 67-68 % HAO for GCP Glass Fill specimens. Cells exposed to CSC over 24 h remained viable and even increased in number. Both cell types adhered almost equally well to CSC and GC Fuji II LC. GCP Glass Fill continued to decrease cell viability and adhesion. CSC-based materials and GC Fuji II LC allowed for HGF and hFOB proliferation; however, none of the tested materials specifically stimulated cell proliferation. CSC characterized by low cytotoxicity. GC Fuji II LC shows moderate cytotoxic effects. ProRoot MTA, Harvard MTA, Biodentine, EndoSequence putty, and GC Fuji II LC allow HGF and HAO to adhere and HGF and hFOB to proliferate. GCP Glass Fill decreases cell viability, adhesion, and proliferation. CSC remain the paramount biologic choice for the repair of extensive cervical root defects. GC Fuji II LC might be considered in addition to CSC when the defect comprises supracrestal areas and the restoration requires superior aesthetic and mechanical characteristics.

  10. Incremental lines in root cementum of human teeth: An approach to their role in age estimation using polarizing microscopy

    Directory of Open Access Journals (Sweden)

    Aggarwal Pooja

    2008-01-01

    Full Text Available Age estimation is an important factor in the identification of an individual in forensic science. The hard tissues of the human dentition are able to resist decay and degradation long after other tissues are lost. This resistance has made teeth useful indicators for age calculation. Recent research indicates that tooth cementum annulations (TCA may be used more reliably than any other morphological or histological traits of the adult skeleton for age estimation. The purpose of this study was to examine the correlation between age and the number of incremental lines in human dental cementum and to ascertain the best method of studying cementum with respect to different forms of microscopy. Thirty nonrestorable teeth were extracted from 20 people, and longitudinal ground section of each tooth was prepared. Photomicrographs of the area at the junction of apical and middle third of the root under light and polarized microscope were taken. The cementum was composed of multiple light and dark bands that were counted on the photomicrograph with the help of image analysis software and added to the average eruption time of individual tooth. The predicted age of the individual was thus obtained. Results showed a significant correlation between the predicted age and actual chronological age of the individual. These data indicate that quantitation of cementum annuli is a moderately reliable means for age estimation in humans and polarizing microscopy is a better means of visualizing incremental lines of cementum compared to light microscopy.

  11. [Investigation of root and canal morphology of human primary mandibular second molar by cone-beam CT].

    Science.gov (United States)

    Yang, Chan; Yang, Ran; Zou, Jing

    2013-06-01

    To investigate the root and canal morphology of primary mandibular second molars in a Chinese population by cone-beam CT(CBCT). A total of 305 CBCT images of 305 children aged 4-8 years were collected, who came to West China Dental Hospital from October, 2011 to March, 2012 due to supernumerary teeth, dental trauma, orthodontic treatment or oral maxillofacial tumor. Primary mandibular second molars which roots were full developed, without periapical infection or apical root resorption were enrolled. All the images were analyzed by two researchers. The data were statistically analyzed by software SPSS 19.0. Four hundred and thirty-seven primary mandibular second molars(PMSM) showed single mesial root except one which had two. Three hundred and twenty-five (74.4%) teeth had one distal root, 111(25.4%) teeth had two and one had three. There were 424(97.0%) teeth which had two mesial canals and 13(3.0%) had one.One hundred and three(23.6%) teeth had one distal root with one canal, 222(50.8%) had one distal root with two canals, 106(24.3%) had two distal roots with two canals, 5(1.1%) had two roots with three canals and 1(0.2%) had three roots with three canals. The root canal system of PMSM had ten variants in this study. The prevalence of three-rooted PMSM had significant differences from different genders (P = 0.000) and different sides (P = 0.028). Majority of primary mandibular second molars had two roots, and the minority had three roots. The prevalence of three-rooted molars in males were higher than that in females. Mesial and distal roots of primary mandibular second molars often had two canals.

  12. Human periodontal ligament fibroblast response to PDGF-BB and IGF-1 application on tetracycline HCI conditioned root surfaces.

    Science.gov (United States)

    Gamal, A Y; Mailhot, J M; Garnick, J J; Newhouse, R; Sharawy, M M

    1998-05-01

    The purpose of this study was to investigate the effect of 2 growth factors, platelet-derived growth factor-BB (PDGF-BB) and insulin-like growth factor-1 (IGF-1), alone or in combination, on the adherence of human periodontal ligament fibroblast (PDL) to tetracycline HCl (TTC) conditioned and nonconditioned periodontally involved root surfaces. There were 80 root dentine chips from 80 patients, ranging from 35 to 70 years of age, each with one periodontally involved tooth requiring extraction. A root dentine chip was obtained from the subgingival surface opposite to the periodontal pocket of each extracted tooth. The dentine chips were randomly distributed into one of 8 groups. In group 1, PDL fibroblasts were cultured and allowed to attach on the dentine surface. In group 2, PDL fibroblasts were cultured on a PDGF-BB pre-treated dentine surface and in group 3, they were cultured on a IGF-1 pre-treated dentine surface. In group 4, PDL fibroblasts were cultured on a dentine surface pretreated with a combination of PDGF-BB and IGF-1. In group 5, PDL fibroblasts were cultured and allowed to attach on the TTC conditioned dentine surfaces. In groups 6 and 7, surface of dentine chips were conditioned with TTC and then were treated with PDGF-BB or IGF-1 respectively, followed by placement of PDL fibroblast and cultured. In group 8, dentine surfaces were conditioned with TTC and then pre-treated with a combination of PDGF-BB and IGF-1 before the fibroblasts were cultured. After 24 h of incubation, the media was removed and samples were fixed and processed for SEM at magnifications of x34, x750, x2000. Photographing and evaluation of samples was performed at x750 in which fibroblast adherence was measured by counting cells within a standard test area. The results of the non-TTC conditioned root surfaces demonstrated a significant increase in fibroblasts adherence in the PDGF-BB and combination PDGF-BB/IGF-I treatment groups (groups 2, 4) when compared to the control (group

  13. Progressive plateau root form dental implant osseointegration: A human retrieval study.

    Science.gov (United States)

    Gil, Luiz F; Suzuki, Marcelo; Janal, Malvin N; Tovar, Nick; Marin, Charles; Granato, Rodrigo; Bonfante, Estevam A; Jimbo, Ryo; Gil, Jose N; Coelho, Paulo G

    2015-08-01

    Although preclinical and sparse human histology retrieval studies have shown that the interface between implant and bone is constantly remodeling, no human retrieval database has been developed to determine the effect of functional loading time and other clinical/implant design variables on osseointegration. The present study tested the hypothesis that bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) increase over functional loading time around dental implants. Due to prosthetic retreatment reasons, 93 human implant retrievals from the same manufacturer (Bicon LLC, Boston, MA, USA) were obtained over a period of approximately 15 years. The retrieved implants were under functional loading from 120 days to ∼18 years and were histomorphologic/metrically evaluated. BIC/BAFO were assessed as a function of multiple independent variables: implant surface type, diameter, length, jaw (maxilla/mandible), region (anterior/posterior), and time of functional loading. The results showed that both BIC and BAFO increased over time independently of implant design/clinical variables, supporting the postulated hypothesis. © 2014 Wiley Periodicals, Inc.

  14. The morphology and clinical significance of the dorsal meningovertebra ligaments in the cervical epidural space.

    Science.gov (United States)

    Shi, Benchao; Zheng, Xuefeng; Min, Shaoxiong; Zhou, Zhilai; Ding, Zihai; Jin, Anmin

    2014-11-01

    The dural sac is anchored within the vertebral canal by connective tissue called meningovertebral ligaments in the epidural space. During flavectomy and laminectomy, inadvertent disruption of the dorsal meningovertebral ligaments may lead to dura laceration and cerebrospinal fluid (CSF) leaks. All the described dorsal meningovertebral ligaments were located in the lumbar region. A rare study is available about dorsal meningovertebral ligaments of the cervical spinal dura to the adjacent vertebrae. To identify and describe the dorsal meningovertebral ligaments at each cervical level and discuss their clinical significance. A dissection-based study of 22 embalmed cadavers. The anatomy was studied in 22 whole cervical cadavers (11 females, 11 males), prepared with formaldehyde, whose ages at the time of death ranged from 55 to 78 years. The vertebral canal was divided to expose the dural sac and the spinal nerve roots. At all levels of the cervical vertebra, the morphology, quantity, origin, insertion, and spatial orientation of the dorsal meningovertebral ligaments were determined and the length, width or diameter, and thickness of the ligaments were measured with vernier calipers. The dorsal meningovertebral ligaments in the cervical region anchored the posterior dural sac to the ligamentum flavum or laminae. The number of attachment points on the ligamentum flavum was relatively larger than that on the lamina, and the occurrence rate of dorsal meningovertebral ligaments was 100% at C1-C2 and C4--C5. The thickest ligaments were observed at the C1 and C2 vertebrae. The length of the ligaments varied from 1.50 to 35.22 mm, and the orientation of the ligaments mostly was craniocaudal. The morphology of the dorsal meningovertebral ligaments was divided into four types: strip type, cord type, grid type, and thin slice type. In the cervical spine, the dorsal meningovertebral ligaments exist between the posterior dural sac and the ligamentum flavum or lamina. The dorsal

  15. Electroacupuncture reduces the evoked responses of the spinal dorsal horn neurons in ankle-sprained rats

    OpenAIRE

    Kim, Jae Hyo; Kim, Hee Young; Chung, Kyungsoon; Chung, Jin Mo

    2011-01-01

    Acupuncture is shown to be effective in producing analgesia in ankle sprain pain in humans and animals. To examine the underlying mechanisms of the acupuncture-induced analgesia, the effects of electroacupuncture (EA) on weight-bearing forces (WBR) of the affected foot and dorsal horn neuron activities were examined in a rat model of ankle sprain. Ankle sprain was induced manually by overextending ligaments of the left ankle in the rat. Dorsal horn neuron responses to ankle movements or compr...

  16. Diagnostic Accuracy of Periapical Radiography and Cone-beam Computed Tomography in Identifying Root Canal Configuration of Human Premolars.

    Science.gov (United States)

    Sousa, Thiago Oliveira; Haiter-Neto, Francisco; Nascimento, Eduarda Helena Leandro; Peroni, Leonardo Vieira; Freitas, Deborah Queiroz; Hassan, Bassam

    2017-07-01

    The aim of this study was to assess the diagnostic accuracy of periapical radiography (PR) and cone-beam computed tomographic (CBCT) imaging in the detection of the root canal configuration (RCC) of human premolars. PR and CBCT imaging of 114 extracted human premolars were evaluated by 2 oral radiologists. RCC was recorded according to Vertucci's classification. Micro-computed tomographic imaging served as the gold standard to determine RCC. Accuracy, sensitivity, specificity, and predictive values were calculated. The Friedman test compared both PR and CBCT imaging with the gold standard. CBCT imaging showed higher values for all diagnostic tests compared with PR. Accuracy was 0.55 and 0.89 for PR and CBCT imaging, respectively. There was no difference between CBCT imaging and the gold standard, whereas PR differed from both CBCT and micro-computed tomographic imaging (P < .0001). CBCT imaging was more accurate than PR for evaluating different types of RCC individually. Canal configuration types III, VII, and "other" were poorly identified on CBCT imaging with a detection accuracy of 50%, 0%, and 43%, respectively. With PR, all canal configurations except type I were poorly visible. PR presented low performance in the detection of RCC in premolars, whereas CBCT imaging showed no difference compared with the gold standard. Canals with complex configurations were less identifiable using both imaging methods, especially PR. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. Fermented Acanthopanax koreanum Root Extract Reduces UVB- and H2O2-Induced Senescence in Human Skin Fibroblast Cells.

    Science.gov (United States)

    Park, Min-Ja; Bae, Young-Seuk

    2016-07-28

    The present study assessed the effects of an aqueous extract of Acanthopanax koreanum root (AE) and of AE following fermentation by lactic acid bacteria (Lactobacillus plantarum and Bifidobacterium bifidum) (AEF) on human skin fibroblast HS68 cells exposed to ultraviolet B (UVB) irradiation and oxidative stress. AEF effectively antagonized the senescence-associated β-galactosidase staining and upregulation of p53 and p21(Cip1/WAF1) induced by UVB or H2O2 treatment in HS68 cells. It also exhibited excellent antioxidant activities in radical scavenging assays and reduced the intracellular level of reactive oxygen species induced by UVB or H2O2 treatment. The antioxidant and antisenescent activities of AEF were greater than those of nonfermented A. koreanum extract. AEF significantly repressed the UVB- or H2O2-induced activities of matrix metalloproteinase (MMP)-1 and -3, overexpression of MMP-1, and nuclear factor κB (NF-κB) activation. This repression of NF-κB activation and MMP-1 overexpression was attenuated by a mitogen-activated protein kinase activator, suggesting that this AEF activity was dependent on this signaling pathway. Taken together, these data indicated that AEF-mediated antioxidant and anti-photoaging activities may produce anti-wrinkle effects on human skin.

  18. Root hairs

    NARCIS (Netherlands)

    Grierson, C.; Nielsen, E.; Ketelaar, T.; Schiefelbein, J.

    2014-01-01

    Roots hairs are cylindrical extensions of root epidermal cells that are important for acquisition of nutrients, microbe interactions, and plant anchorage. The molecular mechanisms involved in the specification, differentiation, and physiology of root hairs in Arabidopsis are reviewed here. Root hair

  19. Dorsal arthrodesis in prepubertal New Zealand white rabbits followed to skeletal maturity: Effect on thoracic dimensions, spine growth and neural elements

    Directory of Open Access Journals (Sweden)

    Canavese Federico

    2010-01-01

    Full Text Available Background: Several studies have shown that severe spinal deformity and early arthrodesis can adversely affect the development of the spine and thorax by changing their shape and reducing their normal function. This article analyzes the consequences of posterior fusion on the growth of spine, thorax and neural elements in New Zealand white rabbits and compares with similar human data. Materials and Methods : The first section of the article analyzes the consequences of T1-T6 dorsal arthrodesis on the growth of the spine, sternum, thorax volume and neural elements in 12 prepubertal female New Zealand white rabbits, through a study of CT scans and histology specimens. The second part, evaluates thoracic dimensions in 21 children with spinal arthrodesis for treatment of deformity performed prior to nine years of age. Results: Dorsal arthrodesis in prepubertal rabbits changes thoracic growth patterns. In operated rabbits thoracic depth grows more slowly than thoracic width. The sternum as well as length of thoracic vertebral bodies in the spinal segment T1-T6 show reduced growth. Children undergoing spinal arthrodesis before nine years of age were noted to have shortened height, short trunk and disproportionate body habitus at skeletal maturity. Observed spine height and chest dimension values were reduced compared to the expected norms. The ratio between chest width and chest depth was below normal values. Conclusions: The first part of the study shows that thoracic dorsal arthrodesis in prepubertal New Zealand white rabbit influences thoracic, spine growth and affects the shape of pseudo unipolar neurons of the dorsal root ganglia. The second part demonstrates that children treated before nine years of age have significantly reduced spine height and thoracic dimensions. The thorax becomes elliptical as chest depth grows less than chest width. Both experimental and clinical findings contribute to explain reduced chest growth and subsequent thoracic

  20. Caries resistance of lased human root surface with 10.6 μm CO2 laser-thermal, morphological, and microhardness analysis

    Science.gov (United States)

    de Souza-Zaroni, W. C.; Freitas, A. C. P.; Hanashiro, F. S.; Steiner-Oliveira, C.; Nobre-Dos-Santos, M.; Youssef, M. N.

    2010-02-01

    Although the cariostatic effects of CO2 laser on enamel have been shown, its effects on root surface demineralization remains uncertain. The objectives of this in vitro research was to establish safe parameters for a pulsed 10.6 μm CO2 laser and to evaluate its effect on morphological features of the root surface, as well as on the reduction of root demineralization. Ninety-five human root surfaces were randomly divided into five groups: G1-No treatment (control); G2—2.5 J/cm2; G3—4.0 J/cm2; G4—5.0 J/cm2; and G5—6.0 J/cm2. Intrapulpal temperature was evaluated during root surface irradiation by a thermocouple and morphological changes were evaluated by SEM. After the surface treatment, the specimens were submitted to a 7-day pH-cycling model. Subsequently, the cross-sectional Knoop microhardness values were measured. For all irradiated groups, intrapulpal temperature changes were less than 1.5°C. Scanning electron microscopy images indicated that fluences as low as 4.0 J/cm2 were sufficient to induce morphological changes in the root surface. Additionally, for fluences reaching or exceeding 4.0 J/cm2, laser-induced inhibitory effects on root surface demineralization were observed. It was concluded that laser energy density in the range of 4.0 to 6.0 J/cm2 could be applied to a dental root to reduce demineralization of this surface without compromising pulp vitality.

  1. A study of root canal morphology of human primary molars using computerised tomography: An in vitro study

    OpenAIRE

    Zoremchhingi; Joseph T; Varma B; Mungara J

    2005-01-01

    Knowledge of the size, morphology and variation of the root canals of primary teeth are useful in visualizing the pulp cavity during treatment. This study was carried out to investigate the applicability of Computed Tomography in studying the root canal morphology of the primary molars. A total of 60 primary molars.without any macroscopic root resorption were collected and divided into four groups. The samples were arranged in wax block and then scanned for evaluation in the CT Scanner both i...

  2. Synaptically evoked glutamate transporter currents in Spinal Dorsal Horn Astrocytes

    Directory of Open Access Journals (Sweden)

    Dougherty Patrick M

    2009-07-01

    Full Text Available Abstract Background Removing and sequestering synaptically released glutamate from the extracellular space is carried out by specific plasma membrane transporters that are primarily located in astrocytes. Glial glutamate transporter function can be monitored by recording the currents that are produced by co-transportation of Na+ ions with the uptake of glutamate. The goal of this study was to characterize glutamate transporter function in astrocytes of the spinal cord dorsal horn in real time by recording synaptically evoked glutamate transporter currents. Results Whole-cell patch clamp recordings were obtained from astrocytes in the spinal substantia gelatinosa (SG area in spinal slices of young adult rats. Glutamate transporter currents were evoked in these cells by electrical stimulation at the spinal dorsal root entry zone in the presence of bicuculline, strychnine, DNQX and D-AP5. Transporter currents were abolished when synaptic transmission was blocked by TTX or Cd2+. Pharmacological studies identified two subtypes of glutamate transporters in spinal astrocytes, GLAST and GLT-1. Glutamate transporter currents were graded with stimulus intensity, reaching peak responses at 4 to 5 times activation threshold, but were reduced following low-frequency (0.1 – 1 Hz repetitive stimulation. Conclusion These results suggest that glutamate transporters of spinal astrocytes could be activated by synaptic activation, and recording glutamate transporter currents may provide a means of examining the real time physiological responses of glial cells in spinal sensory processing, sensitization, hyperalgesia and chronic pain.

  3. Phenotypic and Functional Characterization of Peripheral Sensory Neurons derived from Human Embryonic Stem Cells

    OpenAIRE

    Alshawaf, Abdullah Jawad; Viventi, Serena; Qiu, Wanzhi; D’Abaco, Giovanna; Nayagam, Bryony; Erlichster, Michael; Chana, Gursharan; Everall, Ian; Ivanusic, Jason; Skafidas, Efstratios; Dottori, Mirella

    2018-01-01

    The dorsal root ganglia (DRG) consist of a multitude of sensory neuronal subtypes that function to relay sensory stimuli, including temperature, pressure, pain and position to the central nervous system. Our knowledge of DRG sensory neurons have been predominantly driven by animal studies and considerably less is known about the human DRG. Human embryonic stem cells (hESC) are valuable resource to help close this gap. Our previous studies reported an efficient system for deriving neural crest...

  4. The issue of ventral versus dorsal approach in bulbar urethral ...

    African Journals Online (AJOL)

    E. Palminteri

    increased over time the use of Ventral Graft and decreased the use of dorsal graft [7]. From surgical point of view, the Barbagli Dorsal Grafting by Dor- sal approach ... seems reduce the risk of fistula; in reality there is a similar rate of fistula with both ventral and dorsal grafting. The disadvantage of the dorsal approach is that it ...

  5. Oral intake of encapsulated dried ginger root powder hardly affects human thermoregulatory function, but appears to facilitate fat utilization

    Science.gov (United States)

    Miyamoto, Mayumi; Matsuzaki, Kentaro; Katakura, Masanori; Hara, Toshiko; Tanabe, Yoko; Shido, Osamu

    2015-10-01

    The present study investigated the impact of a single oral ingestion of ginger on thermoregulatory function and fat oxidation in humans. Morning and afternoon oral intake of 1.0 g dried ginger root powder did not alter rectal temperature, skin blood flow, O2 consumption, CO2 production, and thermal sensation and comfort, or induce sweating at an ambient temperature of 28 °C. Ginger ingestion had no effect on threshold temperatures for skin blood flow or thermal sweating. Serum levels of free fatty acids were significantly elevated at 120 min after ginger ingestion in both the morning and afternoon. Morning ginger intake significantly reduced respiratory exchange ratios and elevated fat oxidation by 13.5 % at 120 min after ingestion. This was not the case in the afternoon. These results suggest that the effect of a single oral ginger administration on the peripheral and central thermoregulatory function is miniscule, but does facilitate fat utilization although the timing of the administration may be relevant.

  6. Shear bond strength of Biodentine, ProRoot MTA, glass ionomer cement and composite resin on human dentine ex vivo.

    Science.gov (United States)

    Kaup, Markus; Dammann, Christoph Heinrich; Schäfer, Edgar; Dammaschke, Till

    2015-04-19

    The aim of this study was to compare the shear bond strength of Biodentine, ProRoot MTA (MTA), glass ionomer cement (GIC) and composite resin (CR) on dentine. 120 extracted human third molars were embedded in cold-cured-resin and grinned down to the dentine. For each material 30 specimens were produced in standardised height and width and the materials were applied according to manufacturers´ instructions on the dentine samples. Only in the CR group a self-etching dentine-adhesive was used. In all other groups the dentine was not pre-treated. All specimens were stored at 37.5 °C and 100% humidity for 2d, 7d and 14d. With a testing device the shear bond strength was determined (separation of the specimens from the dentine surface). The statistical evaluation was performed using ANOVA and Tukey-test (p Biodentine increased significantly compared to the 2d investigation period (p Biodentine showed a significantly higher shear bond strength than MTA (p Biodentine and GIC was not significant (p > 0.05). After 7d Biodentine showed comparable shear bond values than GIC, whereas the shear bond values for MTA were significantly lower even after 14d. The adhesion of Biodentine to dentine surface seams to be superior compared to that of MTA.

  7. Comparison of the antibacterial effect of sodium hypochlorite and aloe vera solutions as root canal irrigants in human extracted teeth contaminated with enterococcus faecalis.

    Science.gov (United States)

    Sahebi, S; Khosravifar, N; Sedighshamsi, M; Motamedifar, M

    2014-03-01

    The main purpose of a root canal treatment is to eliminate the bacteria and their products from the pulp space. Sodium hypochlorite has excellent antibacterial properties, but also some negative features. The aim of the present study is to compare the antimicrobial effect of Aloe Vera solution with sodium hypochlorite on E.faecalis in the root canals of human extracted teeth. Sixty human extracted single rooted teeth were selected for this in vitro study. The teeth recruited in this study had no cracks, internal resorption, external resorption and calcification. Enterococcus faecalis was injected in the root canals of all teeth. The teeth were then divided into three groups randomly. Each group consisted of 20 teeth that were all rinsed with one of the following solutions: sodium hypochlorite 2.5%, Aloe vera and normal saline. Subsequent to rinsing, root canals of all teeth were sampled. The samples were cultured and growth of the bacteria was assessed after 48 hours. The number of colonies of the bacteria was then counted. The difference between the inhibitory effect of Aloe vera and normal saline on E.faecalis was not significant according to independent t-test (p= 0.966). The inhibitory effect of sodium hypochlorite on E.faecalis was much greater than that of Aloe vera and normal saline (pAloe vera solution is not recommended as a root canal irrigator, but future studies are suggested to investigate the antibacterial effect of Aloe vera with longer duration of exposure and as an intra canal medicament.

  8. Neural dynamics of phonological processing in the dorsal auditory stream.

    Science.gov (United States)

    Liebenthal, Einat; Sabri, Merav; Beardsley, Scott A; Mangalathu-Arumana, Jain; Desai, Anjali

    2013-09-25

    Neuroanatomical models hypothesize a role for the dorsal auditory pathway in phonological processing as a feedforward efferent system (Davis and Johnsrude, 2007; Rauschecker and Scott, 2009; Hickok et al., 2011). But the functional organization of the pathway, in terms of time course of interactions between auditory, somatosensory, and motor regions, and the hemispheric lateralization pattern is largely unknown. Here, ambiguous duplex syllables, with elements presented dichotically at varying interaural asynchronies, were used to parametrically modulate phonological processing and associated neural activity in the human dorsal auditory stream. Subjects performed syllable and chirp identification tasks, while event-related potentials and functional magnetic resonance images were concurrently collected. Joint independent component analysis was applied to fuse the neuroimaging data and study the neural dynamics of brain regions involved in phonological processing with high spatiotemporal resolution. Results revealed a highly interactive neural network associated with phonological processing, composed of functional fields in posterior temporal gyrus (pSTG), inferior parietal lobule (IPL), and ventral central sulcus (vCS) that were engaged early and almost simultaneously (at 80-100 ms), consistent with a direct influence of articulatory somatomotor areas on phonemic perception. Left hemispheric lateralization was observed 250 ms earlier in IPL and vCS than pSTG, suggesting that functional specialization of somatomotor (and not auditory) areas determined lateralization in the dorsal auditory pathway. The temporal dynamics of the dorsal auditory pathway described here offer a new understanding of its functional organization and demonstrate that temporal information is essential to resolve neural circuits underlying complex behaviors.

  9. Leaf and root extracts of Moricandia arvensis protect against DNA damage in human lymphoblast cell K562 and enhance antioxidant activity.

    Science.gov (United States)

    Skandrani, Ines; Boubaker, Jihed; Bouhlel, Ines; Limem, Ilef; Ghedira, Kamel; Chekir-Ghedira, Leila

    2010-07-01

    Four extracts were prepared from the roots and leaves of Moricandia arvensis: root chloroform extract (ChlR), leaf chloroform extract (ChlL), root ethyl acetate extract (EAR) and leaf ethyl acetate extract (EAL). The genotoxic and antigenotoxic properties of these extracts were investigated by assessing the induction and inhibition of the genotoxicity induced by the direct-acting mutagen, hydrogen peroxide (H(2)O(2)), using the "Comet assay." It appears that none of the different extracts produces a genotoxic effect, except the highest tested concentrations of the leaf extracts which were capable to eliciting DNA damage. Human lymphoblast cells K562 were pretreated with different concentrations of each extracts and then treated by H(2)O(2), for the antigenotoxic study. The results showed that all extracts inhibited the genotoxicity induced by H(2)O(2) and particularly ChlR (42.5μg/ml) and ChlL (65μg/ml) extracts. In addition, antioxidant potential study of root and leaf extracts using different antioxidant tests indicated that root extracts possess a potent antioxidant activity through namely their capacity to transfer electrons. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. Single-unit analysis of the spinal dorsal horn in patients with neuropathic pain.

    Science.gov (United States)

    Guenot, Marc; Bullier, Jean; Rospars, Jean-Pierre; Lansky, Petr; Mertens, Patrick; Sindou, Marc

    2003-04-01

    Despite the key role played by the dorsal horn of the spinal cord in pain modulation, single-unit recordings have only been performed very rarely in this structure in humans. The authors report the results of a statistical analysis of 64 unit recordings from the human dorsal horn. The recordings were done in three groups of patients: patients with deafferentation pain resulting from brachial plexus avulsion, patients with neuropathic pain resulting from peripheral nerve injury, and patients with pain resulting from disabling spasticity. The patterns of neuronal activities were compared among these three groups. Nineteen neurons were recorded in the dorsal horns of five patients undergoing DREZotomy for a persistent pain syndrome resulting from peripheral nerve injury (i.e., nondeafferented dorsal horns), 31 dorsal horn neurons were recorded in nine patients undergoing DREZotomy for a persistent pain syndrome resulting from brachial plexus avulsion (i.e., deafferented dorsal horns), and 14 neurons were recorded in eight patients undergoing DREZotomy for disabling spasticity. These groups were compared in terms of mean frequency, coefficient of variation of the discharge, other properties of the neuronal discharge studied by the nonparametric test of Wald-Wolfowitz, and the possible presence of bursts. The coefficient of variation tended to be higher in the deafferented dorsal horn group than in the other two groups. Two neurons displaying burst activity could be recorded, both of which belonged to the deafferented dorsal horn group. A significant difference was found in term of neuronal behavior between the peripheral nerve trauma group and the other groups: The brachial plexus avulsion and disabling spasticity groups were very similar, including various types of neuronal behavior, whereas the peripheral nerve lesion group included mostly neurons with "nonrandom" patterns of discharge (i.e., with serial dependency of interspike intervals).

  11. Differential Sampling of Visual Space in Ventral and Dorsal Early Visual Cortex.

    Science.gov (United States)

    Silson, Edward H; Reynolds, Richard C; Kravitz, Dwight J; Baker, Chris I

    2018-02-28

    A fundamental feature of cortical visual processing is the separation of visual processing for the upper and lower visual fields. In early visual cortex (EVC), the upper visual field is processed ventrally, with the lower visual field processed dorsally. This distinction persists into several category-selective regions of occipitotemporal cortex, with ventral and lateral scene-, face-, and object-selective regions biased for the upper and lower visual fields, respectively. Here, using an elliptical population receptive field (pRF) model, we systematically tested the sampling of visual space within ventral and dorsal divisions of human EVC in both male and female participants. We found that (1) pRFs tend to be elliptical and oriented toward the fovea with distinct angular distributions for ventral and dorsal divisions of EVC, potentially reflecting a radial bias; and (2) pRFs in ventral areas were larger (∼1.5×) and more elliptical (∼1.2×) than those in dorsal areas. These differences potentially reflect a tendency for receptive fields in ventral temporal cortex to overlap the fovea with less emphasis on precise localization and isotropic representation of space compared with dorsal areas. Collectively, these findings suggest that ventral and dorsal divisions of EVC sample visual space differently, likely contributing to and/or stemming from the functional differentiation of visual processing observed in higher-level regions of the ventral and dorsal cortical visual pathways. SIGNIFICANCE STATEMENT The processing of visual information from the upper and lower visual fields is separated in visual cortex. Although ventral and dorsal divisions of early visual cortex (EVC) are commonly assumed to sample visual space equivalently, we demonstrate systematic differences using an elliptical population receptive field (pRF) model. Specifically, we demonstrate that (1) ventral and dorsal divisions of EVC exhibit diverging distributions of pRF angle, which are biased

  12. Antiviral activity and possible mechanism of action of constituents identified in Paeonia lactiflora root toward human rhinoviruses.

    Directory of Open Access Journals (Sweden)

    Luong Thi My Ngan

    Full Text Available Human rhinoviruses (HRVs are responsible for more than half of all cases of the common cold and cost billions of USD annually in medical visits and missed school and work. An assessment was made of the antiviral activities and mechanisms of action of paeonol (PA and 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (PGG from Paeonia lactiflora root toward HRV-2 and HRV-4 in MRC5 cells using a tetrazolium method and real-time quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. Results were compared with those of a reference control ribavirin. Based on 50% inhibitory concentration values, PGG was 13.4 and 18.0 times more active toward HRV-2 (17.89 μM and HRV-4 (17.33 μM in MRC5 cells, respectively, than ribavirin. The constituents had relatively high selective index values (3.3->8.5. The 100 μg/mL PA and 20 μg/mL PGG did not interact with the HRV-4 particles. These constituents inhibited HRV-4 infection only when they were added during the virus inoculation (0 h, the adsorption period of HRVs, but not after 1 h or later. Moreover, the RNA replication levels of HRVs were remarkably reduced in the MRC5 cultures treated with these constituents. These findings suggest that PGG and PA may block or reduce the entry of the viruses into the cells to protect the cells from the virus destruction and abate virus replication, which may play an important role in interfering with expressions of rhinovirus receptors (intercellular adhesion molecule-1 and low-density lipoprotein receptor, inflammatory cytokines (interleukin (IL-6, IL-8, tumor necrosis factor, interferon beta, and IL-1β, and Toll-like receptor, which resulted in diminishing symptoms induced by HRV. Global efforts to reduce the level of synthetic drugs justify further studies on P. lactiflora root-derived materials as potential anti-HRV products or lead molecules for the prevention or treatment of HRV.

  13. Antiviral activity and possible mechanism of action of constituents identified in Paeonia lactiflora root toward human rhinoviruses.

    Science.gov (United States)

    Ngan, Luong Thi My; Jang, Myeong Jin; Kwon, Min Jung; Ahn, Young Joon

    2015-01-01

    Human rhinoviruses (HRVs) are responsible for more than half of all cases of the common cold and cost billions of USD annually in medical visits and missed school and work. An assessment was made of the antiviral activities and mechanisms of action of paeonol (PA) and 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose (PGG) from Paeonia lactiflora root toward HRV-2 and HRV-4 in MRC5 cells using a tetrazolium method and real-time quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. Results were compared with those of a reference control ribavirin. Based on 50% inhibitory concentration values, PGG was 13.4 and 18.0 times more active toward HRV-2 (17.89 μM) and HRV-4 (17.33 μM) in MRC5 cells, respectively, than ribavirin. The constituents had relatively high selective index values (3.3->8.5). The 100 μg/mL PA and 20 μg/mL PGG did not interact with the HRV-4 particles. These constituents inhibited HRV-4 infection only when they were added during the virus inoculation (0 h), the adsorption period of HRVs, but not after 1 h or later. Moreover, the RNA replication levels of HRVs were remarkably reduced in the MRC5 cultures treated with these constituents. These findings suggest that PGG and PA may block or reduce the entry of the viruses into the cells to protect the cells from the virus destruction and abate virus replication, which may play an important role in interfering with expressions of rhinovirus receptors (intercellular adhesion molecule-1 and low-density lipoprotein receptor), inflammatory cytokines (interleukin (IL)-6, IL-8, tumor necrosis factor, interferon beta, and IL-1β), and Toll-like receptor, which resulted in diminishing symptoms induced by HRV. Global efforts to reduce the level of synthetic drugs justify further studies on P. lactiflora root-derived materials as potential anti-HRV products or lead molecules for the prevention or treatment of HRV.

  14. Root fractures

    DEFF Research Database (Denmark)

    Andreasen, Jens Ove; Christensen, Søren Steno Ahrensburg; Tsilingaridis, Georgios

    2012-01-01

    The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed.......The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed....

  15. Hexane extract of Raphanus sativus L. roots inhibits cell proliferation and induces apoptosis in human cancer cells by modulating genes related to apoptotic pathway.

    Science.gov (United States)

    Beevi, Syed Sultan; Mangamoori, Lakshmi Narasu; Subathra, Murugan; Edula, Jyotheeswara Reddy

    2010-09-01

    Raphanus sativus, a common cruciferous vegetable has been attributed to possess a number of pharmacological and therapeutic properties. It has been used in indigenous system of medicine for the treatment of various human ailments in India. This present study evaluated the chemopreventive efficacy of different parts of R. sativus such as root, stem and leaves, extracted with solvents of varying polarity and investigated the molecular mechanism leading to growth arrest and apoptotic cell death in human cancer cell lines. Of the different parts, significant growth inhibitory effect was observed with hexane extract of R. sativus root. Analysis of hexane extract by GC-MS revealed the presence of several isothiocyanates (ITCs) such as 4-(methylthio)-3-butenyl isothiocyanate (MTBITC), 4-(methylthio)-3-butyl isothiocyanate (erucin), 4-methylpentyl isothiocyanate, 4-pentenyl isothiocyanate and sulforaphene. R. sativus root extract induced cell death both in p53 proficient and p53 deficient cell lines through induction of apoptotic signaling pathway regardless of the p53 status of cells. The molecular mechanisms underlying R. sativus-induced apoptosis may involve interactions among Bcl(2) family genes, as evidenced by up-regulation of pro-apoptotic genes and down-regulation of anti-apoptotic genes along with activation of Caspase-3. Our findings present the first evidence that hexane extract of R. sativus root exerts potential chemopreventive efficacy and induces apoptosis in cancer cell lines through modulation of genes involved in apoptotic signaling pathway.

  16. A study of root canal morphology of human primary molars using computerised tomography: An in vitro study

    Directory of Open Access Journals (Sweden)

    Zoremchhingi

    2005-03-01

    Full Text Available Knowledge of the size, morphology and variation of the root canals of primary teeth are useful in visualizing the pulp cavity during treatment. This study was carried out to investigate the applicability of Computed Tomography in studying the root canal morphology of the primary molars. A total of 60 primary molars.without any macroscopic root resorption were collected and divided into four groups. The samples were arranged in wax block and then scanned for evaluation in the CT Scanner both in axial and coronal plane. The results obtained from the scanned images were statistically analyzed to know the frequency, mean and standard deviation for all the groups. The images showed the complexity of the root canals of the primary molars and also several capabilities of the CT Scan in advance Endodontic research in primary teeth were observed.

  17. Promutagen activation of triazine herbicides metribuzin and ametryn through Vicia faba metabolism inducing sister chromatid exchanges in human lymphocytes in vitro and in V. faba root tip meristems.

    Science.gov (United States)

    Flores-Maya, Saúl; Gómez-Arroyo, Sandra; Calderón-Segura, María Elena; Villalobos-Pietrini, Rafael; Waliszewski, Stefan M; de la Cruz, Leticia Gómez

    2005-03-01

    The aim of our study was the induction of sister chromatid exchanges (SCE) in human lymphocytes in vitro and in root tip meristems of Vicia faba to evaluate the genotoxic effects of metribuzin and ametryn. Direct treatments of these herbicides on human lymphocytes in vitro applied 24 h after the beginning of culture did not induce SCE; however, they showed a cytotoxic effect in the cultures expressed as cellular death. On the contrary, when extracts of V. faba roots, treated for 4 h with metribuzin and ametryn (in vivo activation), were added to the lymphocyte cultures, SCEs were significantly induced with an asymptotic response. Negative responses appeared with the in vitro assays, in which metribuzin and ametryn were added directly to the 48 h lymphocyte cultures for 4 h. Nevertheless, in treatments in which the S10 metabolic mix was added, the SCE frequencies were significantly different to the control, although a concentration-response relationship was only observed with metribuzin. The results showed that both herbicides needed the V. faba metabolism to produce SCE in human lymphocyte cultures. Metribuzin and ametryn applied to V. faba root tip meristems for 4 h increased SCE frequency significantly, and a concentration-response relationship was observed with both herbicides.

  18. The Main Symptoms in Dorsal Sleep Apnea - Hypopnea Syndrome

    Directory of Open Access Journals (Sweden)

    Mihaela Alexandra POP

    2014-09-01

    Full Text Available OSAHS is a chronic, multifactorial disease, accompanied by significant and complex symptoms. The aim of this study was to evaluate the relationship between OSAHS and dorsal AHI in order to improve early diagnosis of dorsal sleep apnea-hypopnea syndrome. There were significant statistical differences between: the dorsal AHI Mean of the group without excessive daytime sleepiness as opposed to the dorsal AHI Mean of the group with excessive daytime sleepiness; the dorsal AHI Mean of the group without snoring as opposed to the dorsal AHI Mean of the group with snoring; the dorsal AHI Mean of the group without restless sleep as opposed to the dorsal AHI Mean of the group with restless sleep; the dorsal AHI Mean of the group without dyspnea as opposed to the dorsal AHI Mean of the group with dyspnea; the dorsal AHI Mean of the group without night sweats as opposed to the dorsal AHI Mean of the group with night sweats; the dorsal AHI Mean of the group without irritability as opposed to the dorsal AHI Mean of the group with irritability and the dorsal AHI Mean of the group without nightmares as opposed to the dorsal AHI Mean of the group with nightmares. Through this study we highlighted that excessive daytime sleepiness and snoring are prevalent symptoms in dorsal OSAHS. The presence of these symptoms in patients with sleep disorders may improve early diagnosis and the choice of an appropriate treatment for dorsal sleep apnea- hypopnea syndrome, thus participating in improving the patient’s life quality

  19. Assessment of radiographer CT-guided dorsal ganglion block

    Energy Technology Data Exchange (ETDEWEB)

    Booth, T.C., E-mail: tombooth@doctors.org.uk [Department of Radiology, Royal Free Hospital NHS Trust, Pond Street, London NW3 2QG (United Kingdom); Edwards, D.; Platts, A.D.; Savy, L.E. [Department of Radiology, Royal Free Hospital NHS Trust, Pond Street, London NW3 2QG (United Kingdom)

    2011-08-15

    Purpose: Radiographer-performed, CT-guided, therapeutic dorsal ganglion block (DGB) for lumbar radiculopathy was prospectively evaluated for firstly, short-term pain outcomes and secondly, complications. Methods: A prospective outcome audit was undertaken for all patients with radiculopathic pain undergoing radiographer-performed CT-guided DGB over a 12 month period. The indicators and standards were derived from published evidence. The complications were analysed by a neuroradiologist retrospectively. Findings: The pain indicator was defined as 'the percentage of patients referred for CT-guided DGB experiencing improvement or resolution of pain at two weeks post-procedure'. The standard chosen was 64% thus with an outcome of 67% the target was achieved. The complication indicator was defined as 'the percentage of all patients referred for CT-guided DGB who were complication-free over two weeks'. The standard chosen was 97% thus with an outcome of 81% the target was not achieved. Complications resulted from positioning or inaccurate nerve root selection. Conclusion: Radiographer CT-guided DGB is effective in improving or removing pain at two weeks post-procedure. It is safe and not associated with major complications. However, less patients were complication-free following DGB than would be expected. Pre-procedural review of the patient's MRI by a neuroradiologist is recommended to avoid incorrect nerve root selection.

  20. Body weight management effect of burdock (Arctium lappa L.) root is associated with the activation of AMP-activated protein kinase in human HepG2 cells.

    Science.gov (United States)

    Kuo, Daih-Huang; Hung, Ming-Chi; Hung, Chao-Ming; Liu, Li-Min; Chen, Fu-An; Shieh, Po-Chuen; Ho, Chi-Tang; Way, Tzong-Der

    2012-10-01

    Burdock (Arcticum lappa L.) root is used in folk medicine and also as a vegetable in Asian countries. In the present study, burdock root treatment significantly reduced body weight in rats. To evaluate the bioactive compounds, we successively extracted the burdock root with ethanol (AL-1), and fractionated it with n-hexane (AL-2), ethyl acetate (AL-3), n-butanol (AL-4), and water (AL-5). Among these fractions, AL-2 contained components with the most effective hypolipidemic potential in human hepatoma HepG2 cells. AL-2 decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Three active compounds were identified from the AL-2, namely α-linolenic acid, methyl α-linolenate, and methyl oleate. These results suggest that burdock root is expected to be useful for body weight management. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Transseptal dorsal approaches to the wrist.

    Science.gov (United States)

    Zemirline, Ahmed; Hoël, Gérard; Naïto, Kiyohito; Uguen, Arnaud; Liverneaux, Philippe; Le Nen, Dominique

    2013-04-01

    The dorsal approach to the wrist is the exposure of choice for most of the surgical procedures on the radiocarpal and intercarpal joints. Contrary to the volar approach, it encounters neither the main arteries nor the motor nerve branch. However, the dorsal approach goes necessarily through the extensor retinaculum. We describe two transseptal dorsal approaches that pass through the extensor retinaculum in the thickness of a septum between two compartments. A virtual space was developed beneath the infratendinous retinaculum (which is a deep layer covering the floor of the extensor compartments) to expose the periosteum, the ligaments and the joint capsule without opening the extensor compartments. Twenty cadaveric wrists have been dissected to study the feasibility of the two transseptal approaches. Ten wrists were exposed through a 3-4 transseptal approach, passing through the extensor retinaculum in the thickness of the septum between the third and fourth compartments. Ten wrists were exposed through a 4-5 transseptal approach, passing through the extensor retinaculum in the thickness of the septum between the fourth and fifth compartments. The extent of violations of extensor compartments and joint capsule, and the exposed anatomical structures were noted. At the end of each dissection, the whole extensor system was outrightly removed for histological study. The feasibility of the transseptal approaches was demonstrated for all the dissected wrists. The dissection plane beneath the infratendinous retinaculum was macroscopically and microscopically highlighted. The transseptal approaches provide a good exposure to the dorsal side of the wrist joint, without opening the extensor tendon compartments.

  2. Complex Dorsal Metacarpophalangeal Joint Dislocation of Index ...

    African Journals Online (AJOL)

    Complex dorsal metacarpophalangeal dislocation is uncommon. The failure of closed reduction is established. This case report highlights the problem within context of a developing country. The various factors responsible for irreducibilty are reviewed and approaches to surgical treatment discussed in the review of world ...

  3. Investigation of Antibacterial and Antioxidant Activities of Alcoholic Extracts of Flower and Root of Dendrostellera Lesserti on Some Human Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    M. Alamhulu

    2015-01-01

    Full Text Available Introduction & Objective: With increasing the information about the dangerous side effects of synthetic antibiotics , the demand for natural alternative of these drugs has increased. The purpose of this study is to investigate the antibacterial and antioxidant properties of root and flower extracts of the medicinal plant of Dendrostellera lesserti against some human pathogenic bacteria. Materials & Methods: In this experimental study, Dendrostellera lesserti was collected from Hamadan province in 2013. After identification, the extracts were prepared by maceration method. Antibacterial activities were determined by the agar well diffusion method, MIC (serial dilution method and MBC. Antioxidant properties by DPPH method and amount of phenolic and flavonoid were measured by Folin-ciocalteu and aluminum chloride methods , respectively. The data were analyzed using sas software version 9.2 (P<0.05. Results: The largest growth inhibition zone with diameter of 21.33±.66 mm was seen in Salmonella typhi culture against root methanolic extract. MIC and MBC of root extract was lower in comparison with flower. Methanolic extract of flower in at concentration of 0.8 mg/ml had the highest scavenging percentage of free radical. The higher amount of phenol and flavonoid was related to methanol extract of root, 111.8±2.69 mgGAE/g and 2.25±0.35 mgQ/g, respectively Conclusion: According to the obtained results, the root and flower methanolic extracts of Dendrostellera lesserti contain compounds with antibacterial and antioxidant properties. (Sci J Hamadan Univ Med Sci 2015; 21(4:277-285

  4. Human Pulp Responses to Partial Pulpotomy Treatment with TheraCal as Compared with Biodentine and ProRoot MTA: A Clinical Trial.

    Science.gov (United States)

    Bakhtiar, Hengameh; Nekoofar, Mohammad Hossein; Aminishakib, Pouyan; Abedi, Fatemeh; Naghi Moosavi, Fereshteh; Esnaashari, Ehsan; Azizi, Arash; Esmailian, Samar; Ellini, Mohammad Reza; Mesgarzadeh, Vahid; Sezavar, Mehdi; About, Imad

    2017-11-01

    Questions exist regarding the efficacy of resin-containing materials such as TheraCal directly applied on the pulp. This study sought to investigate the clinical efficacy of TheraCal as compared with Biodentine and ProRoot mineral trioxide aggregate (MTA) for partial pulpotomy. In this clinical trial, partial pulpotomy was performed for 27 sound human maxillary and mandibular third molars scheduled for extraction. The teeth were randomly divided into 3 groups (n = 9) and underwent partial pulpotomy with TheraCal, Biodentine, and ProRoot MTA. The teeth were then restored with glass ionomer cement. Clinical and electric pulp tests were performed after 1 and 8 weeks. The teeth were radiographed and extracted at 8 weeks. Histologic sections were prepared and analyzed for pulp inflammation and dentinal bridge formation. Data were analyzed by using one-way analysis of variance. Clinical examination showed no sensitivity to heat, cold, or palpation in ProRoot MTA and Biodentine groups. Two patients in TheraCal group (20%) reported significant pain at 1 week. Periapical radiographs showed no periapical pathology, and electric pulp test revealed a normal pulp response with no hypersensitivity. Inflammation was absent with all materials at 8 weeks. Normal pulp organization was seen in 33.33% of the teeth in ProRoot MTA, 11.11% in TheraCal, and 66.67% in Biodentine group (P = .06). Biodentine group showed complete dentinal bridge formation in all teeth, whereas this rate was 11% and 56% in TheraCal and ProRoot MTA groups, respectively (P = .001). Overall, Biodentine and MTA performed better than TheraCal when used as partial pulpotomy agent and presented the best clinical outcomes. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  5. An isoflavonoid-enriched extract from Pueraria lobata (kudzu) root protects human umbilical vein endothelial cells against oxidative stress induced apoptosis.

    Science.gov (United States)

    Gao, Ying; Wang, Xu; He, Chunnian

    2016-12-04

    Reactive oxygen species (ROS) mediate vascular cell dysfunction and lead to atherosclerosis and other chronic cardiovascular diseases. The root of Pueraria lobata (Willd.) Ohwi, also known as kudzu or Gegen (Chinese name), is one of the most important herbs in traditional Chinese medicine and has been widely used in the treatment of cardiovascular diseases, diabetes, osteonecrosis and neurodegradation diseases. In this study, an ethanol extract from kudzu root was prepared and the in vitro protective effect of the kudzu root extract (KUD) on human umbilical vein endothelial cells (HUVECs) was investigated. An ethanol extract of dried kudzu root was purified with an AB-8 resin column, and the concentrations of puerarin, daidzin and daidzein in the KUD were determined using UV spectroscopy. HUVECs were pretreated with various concentrations of the KUD with or without rotenone and the viability was assessed by AlamarBlue cell viability assay. Next, HUVECs were pretreated with the KUD and then treated with rotenone, and the levels of ROS generation, apoptosis, and changes of the mitochondrial membrane potential (ΔΨm) in HUVECs were measured using fluorescent staining assay and high-content analysis. The contents of three major isoflavonoids (puerarin, daidzin and daidzein) were enriched by 7.75-27.51 fold in the extract. The KUD enhanced the proliferation of HUVECs, and protected HUVECs against rotenone-induced oxidative stress and apoptosis. Additionally, the KUD prevented the loss of ΔΨm in HUVECs stimulated by oxidative stress. We demonstrated that an isoflavonoid-rich extract prepared from kudzu root has the potential to act as a protector for vascular endothelial cells against intracellular ROS mediated apoptosis and mitochondrial damage. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Xenon inhibits excitatory but not inhibitory transmission in rat spinal cord dorsal horn neurons

    Science.gov (United States)

    2010-01-01

    Background The molecular targets for the promising gaseous anaesthetic xenon are still under investigation. Most studies identify N-methyl-D-aspartate (NMDA) receptors as the primary molecular target for xenon, but the role of α-amino-3-hydroxy-5-methyl-4-isoxazole-4-propionic acid (AMPA) receptors is less clear. In this study we evaluated the effect of xenon on excitatory and inhibitory synaptic transmission in the superficial dorsal horn of the spinal cord using in vitro patch-clamp recordings from rat spinal cord slices. We further evaluated the effects of xenon on innocuous and noxious stimuli using in vivo patch-clamp method. Results In vitro, xenon decreased the amplitude and area under the curve of currents induced by exogenous NMDA and AMPA and inhibited dorsal root stimulation-evoked excitatory postsynaptic currents. Xenon decreased the amplitude, but not the frequency, of miniature excitatory postsynaptic currents. There was no discernible effect on miniature or evoked inhibitory postsynaptic currents or on the current induced by inhibitory neurotransmitters. In vivo, xenon inhibited responses to tactile and painful stimuli even in the presence of NMDA receptor antagonist. Conclusions Xenon inhibits glutamatergic excitatory transmission in the superficial dorsal horn via a postsynaptic mechanism. There is no substantial effect on inhibitory synaptic transmission at the concentration we used. The blunting of excitation in the dorsal horn lamina II neurons could underlie the analgesic effect of xenon. PMID:20444263

  7. Antimicrobial efficacy of chlorine dioxide against Candida albicans in stationary and starvation phases in human root canal: An in-vitro study

    Directory of Open Access Journals (Sweden)

    Shirur Krishnaraj Somayaji

    2014-01-01

    Full Text Available Introduction: Candida albicans (C. albicans is the most commonly isolated fungal pathogen from dental root canal. C. albicans forms biofilm and develops resistance against root canal irrigants . This study determines the fungicidal efficacy of 13.8% chlorine dioxide in extracted human teeth at stationary and starvation phases of C. albicans. Materials and Methods: Teeth were decoronated and coronal portion of the roots were prepared into blocks, which were incubated at 37°C with C. albicans for five days. The samples were treated with chlorine dioxide for 12 and 20 minutes. Total of fifty blocks were taken in the study. Colony-forming units were counted in Sabourauds dextrose agar and scanning electron microscopic observation was done. Data were analyzed by one-way ANOVA and Bonferoni′s post hoc test. Results: Teeth at stationary phase (12 min showed mean colony count of 28,000 ± 1814 which is significantly (P < 0.001 less than control group. Teeth at starvation phase (12 min showed colony count of 65,600 ± 1912 which is also significantly (P < 0.001 less than control group. Teeth irrigated at stationary phase (20 min showed mean colony count of 23,400 ± 1776 (P < 0.001. Teeth irrigated at starvation phase (20 min showed mean colony count of 48,100 ± 1663 which is also significantly (P < 0.001 less than that of control group. Conclusion: Treatment of chlorine dioxide reduces the C. albicans count in root canals of extracted human teeth at stationary and starvation phases. Efficacy of chlorine dioxide against C. albicans is relatively higher in stationary phase than that of starvation phase.

  8. Comparative anatomy of the dorsal hump in mature Pacific salmon.

    Science.gov (United States)

    Susuki, Kenta; Ban, Masatoshi; Ichimura, Masaki; Kudo, Hideaki

    2017-07-01

    Mature male Pacific salmon (Genus Oncorhynchus) demonstrate prominent morphological changes, such as the development of a dorsal hump. The degree of dorsal hump formation depends on the species in Pacific salmon. It is generally accepted that mature males of sockeye (O. nerka) and pink (O. gorbuscha) salmon develop most pronounced dorsal humps. The internal structure of the dorsal hump in pink salmon has been confirmed in detail. In this study, the dorsal hump morphologies were analyzed in four Pacific salmon species inhabiting Japan, masu (O. masou), sockeye, chum (O. keta), and pink salmon. The internal structure of the dorsal humps also depended on the species; sockeye and pink salmon showed conspicuous development of connective tissue and growth of bone tissues in the dorsal tissues. Masu and chum salmon exhibited less-pronounced increases in connective tissues and bone growth. Hyaluronic acid was clearly detected in dorsal hump connective tissue by histochemistry, except for in masu salmon. The lipid content in dorsal hump connective tissue was richer in masu and chum salmon than in sockeye and pink salmon. These results revealed that the patterns of dorsal hump formation differed among species, and especially sockeye and pink salmon develop pronounced dorsal humps through both increases in the amount of connective tissue and the growth of bone tissues. In contrast, masu and chum salmon develop their dorsal humps by the growth of bone tissues, rather than the development of connective tissue. © 2017 Wiley Periodicals, Inc.

  9. Immunolocalization of RANK and RANKL along the root surface and in the periodontal membrane of human primary and permanent teeth

    DEFF Research Database (Denmark)

    Bille, Marie-Louise Bastholm; Thomsen, Bjarke; Andersen, Thomas Levin

    2012-01-01

    in odontoblasts and in cells along denticles in one primary tooth. RANK was located in mononuclear cells in the pulp and in multinucleated odontoclasts along resorbed root surfaces and along resorbed dentin surfaces in the pulp in primary teeth and one permanent tooth. Conclusions. This study demonstrated RANK...

  10. Deep dorsal vein arterialisation in vascular impotence.

    Science.gov (United States)

    Wespes, E; Corbusier, A; Delcour, C; Vandenbosch, G; Struyven, J; Schulman, C C

    1989-11-01

    A series of 12 patients with vasculogenic impotence (4 arterial lesions; 8 arterial and venous lesions) underwent deep dorsal vein arterialisation after pre-operative assessment by a multidisciplinary approach. Cumulative graft patency was 58% (7 of 12 patients) up to 21 months but only 4 patients developed almost normal erections. Digital angiography, with and without the intracavernous injection of papaverine, was performed during follow-up to determine the vascular physiological status. At flaccidity, the corpora cavernosa were never opacified in the absence of a venocorporeal shunt. The penile glans was always visualised. Opacification of the deep dorsal vein and the circumflex system decreased with penile rigidity, resulting from their compression between Buck's fascia and the tunica albuginea. Intracavernous pressure recorded before and after the surgical procedure showed a marked increase when a caverno-venous shunt was performed. Hypervascularisation of the glans occurred in 2 cases. The relevance of this new surgical technique and its functional mechanism are discussed.

  11. Giant cell tumor of dorsal vertebral body

    Directory of Open Access Journals (Sweden)

    Rakesh Redhu

    2012-01-01

    Full Text Available A 30-year-old female patient presented with complaints of backache, weakness in both lower limbs and bladder/bowel dysfunction. Imaging showed an osteolytic lesion at tenth dorsal (D10 vertebra with anterior compression on the spinal cord. Complete intralesional tumor excision with reconstruction was carried out using the anterolateral extrapleural approach. Histopathological examination was suggestive of giant cell tumor (GCT. Because of complete intralesional tumor excision and fear of post-radiation osteonecrosis of bone used for delayed bony union, a conservative approach was used, and radiation therapy was not given. After one year of follow-up patient is doing well without any recurrence of the tumor and is ambulant with support. GCT of dorsal vertebral body is an uncommon entity and total en bloc excision is difficult. Therefore, the treatment strategy is not well-defined. We discuss in brief about incidence, presentation and various treatment modalities available for spinal GCT.

  12. Attentional functions in dorsal and ventral simultanagnosia.

    Science.gov (United States)

    Duncan, John; Bundesen, Claus; Olson, Andrew; Humphreys, Glyn; Ward, Robert; Kyllingsbæk, Søren; van Raamsdonk, Monique; Rorden, Chris; Chavda, Swarup

    2003-12-01

    Whole report of brief letter arrays is used to analyse basic attentional deficits in dorsal and ventral variants of simultanagnosia. Using Bundesen's Theory of Visual Attention (TVA), a number of previous theoretical suggestions are formalised and tested, including primary deficit in processing more than one display element, attentional stickiness, foveal bias, and global weakness of the visual representation. Interestingly, data from two cases, one dorsal and one ventral, show little true deficit in simultaneous perception, or selective deficit in those TVA parameters (short-term memory capacity, attentional weighting) specifically associated with multi-element displays. Instead there is a general reduction in speed of visual processing (processing rate in TVA), effective even for a single display element but compounded when two or more elements compete.

  13. Electroacupuncture reduces the evoked responses of the spinal dorsal horn neurons in ankle-sprained rats.

    Science.gov (United States)

    Kim, Jae Hyo; Kim, Hee Young; Chung, Kyungsoon; Chung, Jin Mo

    2011-05-01

    Acupuncture is shown to be effective in producing analgesia in ankle sprain pain in humans and animals. To examine the underlying mechanisms of the acupuncture-induced analgesia, the effects of electroacupuncture (EA) on weight-bearing forces (WBR) of the affected foot and dorsal horn neuron activities were examined in a rat model of ankle sprain. Ankle sprain was induced manually by overextending ligaments of the left ankle in the rat. Dorsal horn neuron responses to ankle movements or compression were recorded from the lumbar spinal cord using an in vivo extracellular single unit recording setup 1 day after ankle sprain. EA was applied to the SI-6 acupoint on the right forelimb (contralateral to the sprained ankle) by trains of electrical pulses (10 Hz, 1-ms pulse width, 2-mA intensity) for 30 min. After EA, WBR of the sprained foot significantly recovered and dorsal horn neuron activities were significantly suppressed in ankle-sprained rats. However, EA produced no effect in normal rats. The inhibitory effect of EA on hyperactivities of dorsal horn neurons of ankle-sprained rats was blocked by the α-adrenoceptor antagonist phentolamine (5 mg/kg ip) but not by the opioid receptor antagonist naltrexone (10 mg/kg ip). These data suggest that EA-induced analgesia in ankle sprain pain is mediated mainly by suppressing dorsal horn neuron activities through α-adrenergic descending inhibitory systems at the spinal level.

  14. Electroacupuncture reduces the evoked responses of the spinal dorsal horn neurons in ankle-sprained rats

    Science.gov (United States)

    Kim, Jae Hyo; Kim, Hee Young; Chung, Kyungsoon

    2011-01-01

    Acupuncture is shown to be effective in producing analgesia in ankle sprain pain in humans and animals. To examine the underlying mechanisms of the acupuncture-induced analgesia, the effects of electroacupuncture (EA) on weight-bearing forces (WBR) of the affected foot and dorsal horn neuron activities were examined in a rat model of ankle sprain. Ankle sprain was induced manually by overextending ligaments of the left ankle in the rat. Dorsal horn neuron responses to ankle movements or compression were recorded from the lumbar spinal cord using an in vivo extracellular single unit recording setup 1 day after ankle sprain. EA was applied to the SI-6 acupoint on the right forelimb (contralateral to the sprained ankle) by trains of electrical pulses (10 Hz, 1-ms pulse width, 2-mA intensity) for 30 min. After EA, WBR of the sprained foot significantly recovered and dorsal horn neuron activities were significantly suppressed in ankle-sprained rats. However, EA produced no effect in normal rats. The inhibitory effect of EA on hyperactivities of dorsal horn neurons of ankle-sprained rats was blocked by the α-adrenoceptor antagonist phentolamine (5 mg/kg ip) but not by the opioid receptor antagonist naltrexone (10 mg/kg ip). These data suggest that EA-induced analgesia in ankle sprain pain is mediated mainly by suppressing dorsal horn neuron activities through α-adrenergic descending inhibitory systems at the spinal level. PMID:21389301

  15. Top-down modulations from dorsal stream in lexical recognition: an effective connectivity FMRI study.

    Directory of Open Access Journals (Sweden)

    Yuan Deng

    Full Text Available Both the ventral and dorsal visual streams in the human brain are known to be involved in reading. However, the interaction of these two pathways and their responses to different cognitive demands remains unclear. In this study, activation of neural pathways during Chinese character reading was acquired by using a functional magnetic resonance imaging (fMRI technique. Visual-spatial analysis (mediated by the dorsal pathway was disassociated from lexical recognition (mediated by the ventral pathway via a spatial-based lexical decision task and effective connectivity analysis. Connectivity results revealed that, during spatial processing, the left superior parietal lobule (SPL positively modulated the left fusiform gyrus (FG, while during lexical processing, the left SPL received positive modulatory input from the left inferior frontal gyrus (IFG and sent negative modulatory output to the left FG. These findings suggest that the dorsal stream is highly involved in lexical recognition and acts as a top-down modulator for lexical processing.

  16. Pain-related synaptic plasticity in spinal dorsal horn neurons: role of CGRP

    Directory of Open Access Journals (Sweden)

    Willis William D

    2006-09-01

    Full Text Available Abstract Background The synaptic and cellular mechanisms of pain-related central sensitization in the spinal cord are not fully understood yet. Calcitonin gene-related peptide (CGRP has been identified as an important molecule in spinal nociceptive processing and ensuing behavioral responses, but its contribution to synaptic plasticity, cellular mechanisms and site of action in the spinal cord remain to be determined. Here we address the role of CGRP in synaptic plasticity in the spinal dorsal horn in a model of arthritic pain. Results Whole-cell current- and voltage-clamp recordings were made from substantia gelatinosa (SG neurons in spinal cord slices from control rats and arthritic rats (> 6 h postinjection of kaolin/carrageenan into the knee. Monosynaptic excitatory postsynaptic currents (EPSCs were evoked by electrical stimulation of afferents in the dorsal root near the dorsal root entry zone. Neurons in slices from arthritic rats showed increased synaptic transmission and excitability compared to controls. A selective CGRP1 receptor antagonist (CGRP8-37 reversed synaptic plasticity in neurons from arthritic rats but had no significant effect on normal transmission. CGRP facilitated synaptic transmission in the arthritis pain model more strongly than under normal conditions where both facilitatory and inhibitory effects were observed. CGRP also increased neuronal excitability. Miniature EPSC analysis suggested a post- rather than pre-synaptic mechanism of CGRP action. Conclusion This study is the first to show synaptic plasticity in the spinal dorsal horn in a model of arthritic pain that involves a postsynaptic action of CGRP on SG neurons.

  17. Bovine pericardium based non-cross linked collagen matrix for successful root coverage, a clinical study in human

    Directory of Open Access Journals (Sweden)

    Schlee Markus

    2012-03-01

    Full Text Available Abstract Introduction The aim of this study was to clinically assess the capacity of a novel bovine pericardium based, non-cross linked collagen matrix in root coverage. Methods 62 gingival recessions of Miller class I or II were treated. The matrix was adapted underneath a coronal repositioned split thickness flap. Clinical values were assessed at baseline and after six months. Results The mean recession in each patient was 2.2 mm at baseline. 6 Months after surgery 86.7% of the exposed root surfaces were covered. On average 0,3 mm of recession remained. The clinical attachment level changed from 3.5 ± 1.3 mm to 1,8 ( ± 0,7 mm during the observational time period. No statistically significant difference was found in the difference of probing depth. An increase in the width of gingiva was significant. With a baseline value of 1.5 ± 0.9 mm an improvement of 2.4 ± 0.8 mm after six month could be observed. 40 out of 62 recessions were considered a thin biotype at baseline. After 6 months all 62 sites were assessed thick. Conclusions The results demonstrate the capacity of the bovine pericardium based non-cross linked collagen matrix for successful root coverage. This material was able to enhance gingival thickness and the width of keratinized gingiva. The percentage of root coverage achieved thereby is comparable to existing techniques. This method might contribute to an increase of patient's comfort and an enhanced aesthetical outcome.

  18. Treatment of right dorsal ulcerative colitis in a horse.

    Science.gov (United States)

    Simmons, T R; Gaughan, E M; Ducharme, N G; Dill, S G; King, J M; Anderson, W I

    1990-02-01

    Excessive administration of phenylbutazone was associated with development of right dorsal ulcerative colitis. The clinical signs of right dorsal colitis include chronic colic and weight loss. The laboratory abnormalities include panhypoproteinemia and a high WBC count in the abdominal fluid. Medical management of the chronic colic and protein-losing enteropathy associated with the ulcerative lesions in the right dorsal colon and surgical bypass of the right dorsal colon did not result in long-term resolution of clinical signs. Resection of the ulcerated right dorsal colon through a right lateral approach at the 16th rib resulted in resolution of intestinal protein loss and colic. The results of this case suggest that surgical resection of the ulcerated right dorsal colon may be the recommended treatment for right dorsal ulcerative colitis.

  19. Therapy-resistant foreign body giant cell granuloma at the periapex of a root-filled human tooth

    Energy Technology Data Exchange (ETDEWEB)

    Nair, P.N.; Sjoegren, U.K.; Krey, G.; Sundqvist, G. (Dental Institute, University of Zurich (Switzerland))

    1990-12-01

    Although the primary etiological factor of periapical lesions is microbial, there are other independent factors that can adversely affect the outcome of endodontic treatment. In this communication, we present morphological evidence in support of the role of a foreign body reaction of periapical tissue to root-filling materials. The specimen consisted of a surgical biopsy of an asymptomatic periapical lesion which persisted after a decade of postendodontic follow-up. The biopsy was processed for correlated light and electron microscopy and was analyzed by various microtechniques. The unique feature of the lesion was the presence of vast numbers of large multinucleated cells and their cytoplasmic inclusion bodies. Morphologically, these multinucleated cells resembled foreign body giant cells. They contained characteristic birefringent cytoplasmic inclusions which on electron-probe x-ray microanalysis consistently revealed the presence of magnesium and silicon. The magnesium and silicon are presumably the remnants of a root-filling excess which protruded into the periapex and had been resorbed during the follow-up period. These observations strongly suggest that in the absence of microbial factors, root-filling materials which contain irritating substances can evoke a foreign body reaction at the periapex, leading to the development of asymptomatic periapical lesions that may remain refractory to endodontic therapy for long periods of time.

  20. Evaluation of Antimicrobial Photodynamic Therapy Using Indocyanine Green and Near-Infrared Diode Laser Against Enterococcus faecalis in Infected Human Root Canals.

    Science.gov (United States)

    Beltes, Charis; Economides, Nikolaos; Sakkas, Hercules; Papadopoulou, Chrissanthy; Lambrianidis, Theodoros

    2017-05-01

    Photodynamic therapy (PDT) is considered a promising adjunct to the currently available endodontic disinfection techniques leading to more effective reduction of intracanal bacteria. The present ex vivo study aimed to assess the antimicrobial effect of PDT using indocyanine green (ICG) as photosensitizer and a near-infrared (NIR) diode laser in root canals of human teeth infected with Enterococcus faecalis. Ninety single-rooted teeth after chemomechanical preparation and sterilization were contaminated with an E. faecalis strain. The specimens were divided, randomly, into eight experimental groups: (1) PDT with ICG and laser (0.5 W output power-medium-energy fluence), (2) PDT with ICG and laser (1 W output power-high-energy fluence), (3) only laser emission, (4) only ICG, (5) 2.5% sodium hypochlorite (NaOCl) as irrigant, (6) 2.5% NaOCl and PDT with ICG and laser, (7) no treatment (positive control), and (8) no bacterial biofilm growth (negative control). The root canal contents were sampled by flushing and the collected washings were plated on an appropriate culture medium, which was incubated for 48 h at 35°C ± 2.0. The colony-forming units (CFUs) were determined to assess the bactericidal effect of the tested experimental combinations. The microbiological tests revealed that PDT groups, regardless of the overall power, showed significant lower mean log 10 CFU levels, than groups 3 and 4 (p  0.05) was observed between groups 1, 2, 5, and 6 and significant difference was noticed between groups 3, 4, and 5 (p PDT activated by an NIR diode laser provided increased disinfection of the root canal system, but the overall benefit in total bacterial elimination should be further investigated.

  1. A Comparison of the Discoloration Potential for EndoSequence Bioceramic Root Repair Material Fast Set Putty and ProRoot MTA in Human Teeth: An In Vitro Study.

    Science.gov (United States)

    Alsubait, S; Al-Haidar, S; Al-Sharyan, N

    2017-02-01

    To compare the discoloration potential of Endosequence Bioceramic Root Repair Material fast set putty (ERRMF) and ProRoot MTA (PMTA) when placed coronally in human extracted teeth over a 4-month period. Forty-eight premolars were sectioned 2 mm below the cementoenamel junction. The pulp chambers were cleaned chemo-mechanically. The specimens were randomly assigned to three groups: PMTA, ERRMF, and no fill (control). Tooth color was measured spectrophotometrically at six time points: after material placement, after 2, 4, 8, 12, and 16 weeks. Data were transformed into Commission Internationale de l'éclairage (CIE) L*a*b* system and color difference values (ΔΕ) were calculated. Specimen images were recorded for each time point. Three random specimens from experimental groups were sectioned longitudinally and examined under a stereomicroscope. For data analyses, we used one-way analysis of variance with repeated measurements and Tukey's test (α = 0.05). At 2 weeks, the ΔE means did not differ significantly between the groups. At 4, 8, 12, and 16 weeks, PMTA group exhibited a significantly higher ΔE compared with the ERRMF and control groups. The ΔE did not differ significantly between the ERRMF and control groups. Teeth restored using PMTA exhibited a visually progressive dark discoloration. The control and ERRMF group specimens exhibited color stability. Sections of PMTA specimens revealed grayish discoloration of the material with dark dentinal staining that was not visible in the ERRMF specimens. Teeth restored using PMTA exhibited progressive discoloration, whereas teeth restored with ERRMF maintained color stability over a 4-month period. The results found in the present study suggest that PMTA produces tooth discoloration over time, whereas ERRMF does not induce tooth discoloration. Therefore, ERRMF might be an alternative to PMTA, especially for coronal restoration in aesthetic zone teeth. (J Esthet Restor Dent 29:59-67, 2017). © 2016 Wiley

  2. Stachbotrys Root Rot

    Science.gov (United States)

    Stachybotrys root rot is caused by Stachybotrys chartarum, a cellulytic saprophytic hyphomycete fungus. The pathogen produces mycotoxins including a host of immunosupressant compounds for human and is one of the causes of the "sick building syndrome." Although S. chartarum is rarely known as a plan...

  3. Metagenomics at Grass Roots

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 22; Issue 3. Metagenomics at Grass Roots. Sudeshna ... benefit human health, agriculture, and ecosystemfunctions. This article provides a brief history of technicaladvances in metagenomics, including DNA sequencing methods,and some case studies.

  4. Functional specialization in dorsal and ventral premotor areas.

    Science.gov (United States)

    Hoshi, Eiji; Tanji, Jun

    2004-01-01

    The premotor cortex (PM) in the bilateral lateral hemisphere of nonhuman primates and the human has been implicated in the sensorial guidance of movements. This is in contrast to more medial motor areas that are involved more in the temporal structuring of movements based on memorized information. The PM is further subdivided into dorsal (PMd) and ventral (PMv) parts. In this chapter, we describe our attempts to find differences in the use of these two areas in a nonhuman primate for programming future motor actions based on visual signals. We show that neurons in the PMv are involved primarily in receiving visuospatial signals and in specifying the spatial location of the target to be reached. In contrast, neurons in the PMd are involved more in integrating information about which arm to use and the target to be reached. Thus, PMd neurons are more implicated than those of the PMv in the preparation for a future motor action.

  5. Hair Growth Promotant Activity of Petroleum Ether Root Extract of ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of Glycyrrhiza glabra root extract on hair growth in female Wistar rats. Methods: Female Wistar rats were used for the hair growth promotion studies. They were divided into three groups(n = 6) and their dorsal skin was completely denuded to completely remove hair. Paraffin oil (control), 2 ...

  6. The predominantly HEAT-like motif structure of huntingtin and its association and coincident nuclear entry with dorsal, an NF-kB/Rel/dorsal family transcription factor

    Directory of Open Access Journals (Sweden)

    Gusella James F

    2002-10-01

    Full Text Available Abstract Background Huntington's disease (HD pathogenesis is due to an expanded polyglutamine tract in huntingtin, but the specificity of neuronal loss compared with other polyglutamine disorders also implies a role for the protein's unknown inherent function. Huntingtin is moderately conserved, with 10 HEAT repeats reported in its amino-terminal half. HD orthologues are evident in vertebrates and Drosophila, but not in Saccharomyces cerevisiae, Caenorhabditis elegans or Arabidopsis thaliana, a phylogenetic profile similar to the NF-kB/Rel/dorsal family transcription factors, suggesting a potential functional relationship. Results We initially tested the potential for a relationship between huntingtin and dorsal by overexpression experiments in Drosophila S2 cells. Drosophila huntingtin complexes via its carboxyl-terminal region with dorsal, and the two enter the nucleus concomitantly, partly in a lipopolysaccharide (LPS- and Nup88-dependent manner. Similarly, in HeLa cell extracts, human huntingtin co-immunoprecipitates with NF-kB p50 but not with p105. By cross-species comparative analysis, we find that the carboxyl-terminal segment of huntingtin that mediates the association with dorsal possesses numerous HEAT-like sequences related to those in the amino-terminal segment. Thus, Drosophila and vertebrate huntingtins are composed predominantly of 28 to 36 degenerate HEAT-like repeats that span the entire protein. Conclusion Like other HEAT-repeat filled proteins, huntingtin is made up largely of degenerate HEAT-like sequences, suggesting that it may play a scaffolding role in the formation of particular protein-protein complexes. While many proteins have been implicated in complexes with the amino-terminal region of huntingtin, the NF-kB/Rel/dorsal family transcription factors merit further examination as direct or indirect interactors with huntingtin's carboxyl-terminal segment.

  7. PROJECTIONS OF DORSAL AND MEDIAN RAPHE NUCLEI TO DORSAL AND VENTRAL STRIATUM

    Directory of Open Access Journals (Sweden)

    G. R. Hassanzadeh G. Behzadi

    2007-08-01

    Full Text Available The ascending serotonergic projections are derived mainly from mesencephalic raphe nuclei. Topographical projections from mesencephalic raphe nuclei to the striatum were examined in the rat by the retrograde transport technique of HRP (horseradish peroxidase. In 29 rats stereotaxically injection of HRP enzyme were performed in dorsal and ventral parts of striatum separately. The extent of the injection sites and distribution of retrogradely labeled neuronal cell bodies were drawed on representative sections using a projection microscope. Following ipsilateral injection of HRP into the dorsal striatum, numerous labeled neurons were seen in rostral portion of dorsal raphe (DR nucleus. In the same level the cluster of labeled neurons were hevier through caudal parts of DR. A few neurons were also located in lateral wing of DR. More caudally some labeled neurons were found in lateral, medial line of DR. In median raphe nucleus (MnR the labeled neurons were scattered only in median portion of this nucleus. The ipsilateral injection of HRP into the ventral region of striatum resulted on labeling of numerous neurons in rostral, caudal and lateral portions of DR. Through the caudal extension of DR on 4th ventricle level, a large number of labeled neurons were distributed along the ventrocaudal parts of DR. In MnR, labeled neurons were observed only in median part of this nucleus. These findings suggest the mesencephalic raphe nuclei projections to caudo-putamen are topographically organized. In addition dorsal and median raphe nuclei have a stronger projection to the ventral striatum.

  8. Isolated dorsal dislocation of the tarsal naviculum.

    Science.gov (United States)

    Hamdi, Kaziz; Hazem, Ben Ghozlen; Yadh, Zitoun; Faouzi, Abid

    2015-01-01

    Isolated dislocation of the tarsal naviculum is an unusual injury, scarcely reported in the literature. The naviculum is surrounded by the rigid bony and ligamentous support hence fracture dislocation is more common than isolated dislocation. The mechanism and treatment options remain unclear. In this case report, we describe a 31 year old man who sustained an isolated dorsal dislocation of the left tarsal naviculum, without fracture, when he was involved in a motor vehicle collision. The reported mechanism of the dislocation is a hyper plantar flexion force applied to the midfoot, resulting in a transient disruption of the ligamentous support of the naviculum bone, with dorsal displacement of the bone. The patient was treated with open reduction and Krischner-wire fixation of the navicular after the failure of closed reduction. The wires were removed after 6 weeks postoperatively. Physiotherapy for stiffness and midfoot pain was recommended for 2 months. At 6 months postoperatively, limping, midfoot pain and weakness were reported, no X-ray abnormalities were found. The patient returned to his obvious activities with a normal range of motion.

  9. Isolated dorsal dislocation of the tarsal naviculum

    Directory of Open Access Journals (Sweden)

    Kaziz Hamdi

    2015-01-01

    Full Text Available Isolated dislocation of the tarsal naviculum is an unusual injury, scarcely reported in the literature. The naviculum is surrounded by the rigid bony and ligamentous support hence fracture dislocation is more common than isolated dislocation. The mechanism and treatment options remain unclear. In this case report, we describe a 31 year old man who sustained an isolated dorsal dislocation of the left tarsal naviculum, without fracture, when he was involved in a motor vehicle collision. The reported mechanism of the dislocation is a hyper plantar flexion force applied to the midfoot, resulting in a transient disruption of the ligamentous support of the naviculum bone, with dorsal displacement of the bone. The patient was treated with open reduction and Krischner-wire fixation of the navicular after the failure of closed reduction. The wires were removed after 6 weeks postoperatively. Physiotherapy for stiffness and midfoot pain was recommended for 2 months. At 6 months postoperatively, limping, midfoot pain and weakness were reported, no X-ray abnormalities were found. The patient returned to his obvious activities with a normal range of motion.

  10. Matching roots to their environment

    Science.gov (United States)

    White, Philip J.; George, Timothy S.; Gregory, Peter J.; Bengough, A. Glyn; Hallett, Paul D.; McKenzie, Blair M.

    2013-01-01

    Background Plants form the base of the terrestrial food chain and provide medicines, fuel, fibre and industrial materials to humans. Vascular land plants rely on their roots to acquire the water and mineral elements necessary for their survival in nature or their yield and nutritional quality in agriculture. Major biogeochemical fluxes of all elements occur through plant roots, and the roots of agricultural crops have a significant role to play in soil sustainability, carbon sequestration, reducing emissions of greenhouse gasses, and in preventing the eutrophication of water bodies associated with the application of mineral fertilizers. Scope This article provides the context for a Special Issue of Annals of Botany on ‘Matching Roots to Their Environment’. It first examines how land plants and their roots evolved, describes how the ecology of roots and their rhizospheres contributes to the acquisition of soil resources, and discusses the influence of plant roots on biogeochemical cycles. It then describes the role of roots in overcoming the constraints to crop production imposed by hostile or infertile soils, illustrates root phenotypes that improve the acquisition of mineral elements and water, and discusses high-throughput methods to screen for these traits in the laboratory, glasshouse and field. Finally, it considers whether knowledge of adaptations improving the acquisition of resources in natural environments can be used to develop root systems for sustainable agriculture in the future. PMID:23821619

  11. Root resorption

    DEFF Research Database (Denmark)

    Kjaer, Inger

    2014-01-01

    formerly been demonstrated how demyelinization of the myelin sheaths in the peripheral nerves close to the root provoke resorption. Accordingly, conditions affecting these tissue layers can be associated not only with different morphologies but also with general symptoms and diseases (e.g., ectodermal...

  12. Root (Botany)

    Science.gov (United States)

    Robert R. Ziemer

    1981-01-01

    Plant roots can contribute significantly to the stability of steep slopes. They can anchor through the soil mass into fractures in bedrock, can cross zones of weakness to more stable soil, and can provide interlocking long fibrous binders within a weak soil mass. In deep soil, anchoring to bedrock becomes negligible, and lateral reinforcement predominates

  13. Effects of organic and conventional growth systems on the content of carotenoids in carrot roots, and on intake and plasma status of carotenoids in humans.

    Science.gov (United States)

    Søltoft, Malene; Bysted, Anette; Madsen, Katja H; Mark, Alicja Budek; Bügel, Susanne G; Nielsen, John; Knuthsen, Pia

    2011-03-15

    The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross-over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems. The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural production system or year, despite differences in fertilisation strategy and levels. The plasma status of carotenoids increased significantly after consumption of the organic and conventional diets, but no systematic differences between the agricultural production systems were observed. The expected higher content of presumed health-promoting carotenoids in organic food products was not documented in this study. Copyright © 2011 Society of Chemical Industry.

  14. New understanding of dorsal dysraphism with lipoma (lipomyeloschisis): radiologic evaluation and surgical correction

    Energy Technology Data Exchange (ETDEWEB)

    Naidich, T.P. (Northwestern Univ., Chicago, IL); McLone, D.G.; Mutluer, S.

    1983-06-01

    The spinal anomaly designated dorsal dysraphism with lipoma (lipomyeloschisis) consists of skin-covered, focal spina bifida; focal partial clefting of the dorsal half of the spinal cord; continuity of the dorsal cleft with the central canal of the cord above (and occasionally below) the cleft; deficiency of the dura underlying the spina bifida; deep extension of subcutaneous lipoma through the spina bifida and the dural deficiency to insert directly into the cleft on the dorsal half of the cord; variable cephalic extension of lipoma into the contiguous central canal of the cord; and variable ballooning of the subarachnoid space to form an associated meningocele. The variable individual expressions of the anomaly are best understood by reference to their archetypal concept. Careful analysis of radiographic and surgical findings in human lipomyeloschisis and correlation with an animal model of lipomyeloschisis indicate that plain spine radiographs and high-resolution metrizamide computed tomographic myelography successfully delineate the precise anatomic derangements associated with lipomyeloschisis and provide the proper basis for planning surgical therapy of this condition.

  15. Direct tactile stimulation of dorsal occipito-temporal cortex in a visual agnosic.

    Science.gov (United States)

    Allen, Harriet A; Humphreys, Glyn W

    2009-06-23

    The human occipito-temporal cortex is preferentially activated by images of objects as opposed to scrambled images. Touching objects (versus textures) also activates this region. We used neuropsychological fMRI to probe whether dorsal regions of the lateral occipital cortex (LO) are activated in tactile recognition without mediation through visual recognition. We tested a patient (HJA) with visual agnosia due to bilateral lesions of the ventral occipito-temporal cortex but spared dorsal LO. HJA's recognition of visual objects was impaired. Nevertheless, his tactile recognition was preserved. We measured brain activity while participants viewed and touched objects and textures. There was overlapping activity in regions including LO and cerebellum for both stimuli for control participants, including new regions not before considered bimodal. For HJA, there were overlapping regions in the intact dorsal LO. Within a subset of the regions found in control participants, HJA showed activity only for tactile objects, suggesting that these regions are specifically involved in successful multimodal recognition. Activation of dorsal LO by tactile input is not secondary to visual recognition but can operate directly through tactile input.

  16. The dorsal prefrontal and dorsal anterior cingulate cortices exert complementary network signatures during encoding and retrieval in associative memory.

    Science.gov (United States)

    Woodcock, Eric A; White, Richard; Diwadkar, Vaibhav A

    2015-09-01

    Cognitive control includes processes that facilitate execution of effortful cognitive tasks, including associative memory. Regions implicated in cognitive control during associative memory include the dorsal prefrontal (dPFC) and dorsal anterior cingulate cortex (dACC). Here we investigated the relative degrees of network-related interactions originating in the dPFC and dACC during oscillating phases of associative memory: encoding and cued retrieval. Volunteers completed an established object-location associative memory paradigm during fMRI. Psychophysiological interactions modeled modulatory network interactions from the dPFC and dACC during memory encoding and retrieval. Results were evaluated in second level analyses of variance with seed region and memory process as factors. Each seed exerted differentiable modulatory effects during encoding and retrieval. The dACC exhibited greater modulation (than the dPFC) on the fusiform and parahippocampal gyrus during encoding, while the dPFC exhibited greater modulation (than the dACC) on the fusiform, hippocampus, dPFC and basal ganglia. During retrieval, the dPFC exhibited greater modulation (than the dACC) on the parahippocampal gyrus, hippocampus, superior parietal lobule, and dPFC. The most notable finding was a seed by process interaction indicating that the dACC and the dPFC exerted complementary modulatory control on the hippocampus during each of the associative memory processes. These results provide evidence for differentiable, yet complementary, control-related modulation by the dACC and dPFC, while establishing the primacy of dPFC in exerting network control during both associative memory phases. Our approach and findings are relevant for understanding basic processes in human memory and psychiatric disorders that impact associative memory-related networks. Copyright © 2015. Published by Elsevier B.V.

  17. Persistent double dorsal aorta: A systematic review of the literature.

    Science.gov (United States)

    Mills, Brandy; Gest, Thomas

    2017-05-01

    Our discovery of a case of persistent double dorsal aorta prompted us to systematically review the literature of all previously reported cases of this anomaly. For our case, we present a completely separated double dorsal aorta, with the right accessory aorta arising from the abdominal aorta and ascending through the aortic hiatus to supply posterior intercostal arteries (PIAs) to the 9th-3rd spaces bilaterally. We examined and compiled data from the 10 previously reported cases, along with our observations from our cadaver, into a systematic review of all known cases of persistent double dorsal aorta. In addition to our case report and systematic review, we investigated the literature focusing on formation of the dorsal aorta in the embryo in order to postulate potential mechanisms for formation of this anomaly. Two variants of persistent double dorsal aorta have been reported in the literature. The first type is characterized by a double-lumen descending aorta with a central dividing septum, and the second features complete separation of the two dorsal aortae. The completely separated variant shows further heterogeneity in the origins of the PIAs and the iliac arteries, and the majority of the reported cases also demonstrate additional anatomical anomalies. We outline the events in embryonic dorsal aorta formation as well as discuss several potential mechanisms that could underlie persistent double dorsal aorta formation. Clin. Anat. 30:517-524, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. Dorsal onlay graft bulbar urethroplasty using buccal mucosa ...

    African Journals Online (AJOL)

    It can be used for penile urethral stricture repair and different types of dorsal onlay graft urethroplasty for bulbar urethral stricture repair. The current paper describes, step by step, Barbagli technique of dorsal onlay graft bulbar urethroplasty using buccal mucosa. The preoperative patient evaluation and postoperative course ...

  19. Human Y chromosome base-substitution mutation rate measured by direct sequencing in a deep-rooting pedigree.

    Science.gov (United States)

    Xue, Yali; Wang, Qiuju; Long, Quan; Ng, Bee Ling; Swerdlow, Harold; Burton, John; Skuce, Carl; Taylor, Ruth; Abdellah, Zahra; Zhao, Yali; MacArthur, Daniel G; Quail, Michael A; Carter, Nigel P; Yang, Huanming; Tyler-Smith, Chris

    2009-09-15

    Understanding the key process of human mutation is important for many aspects of medical genetics and human evolution. In the past, estimates of mutation rates have generally been inferred from phenotypic observations or comparisons of homologous sequences among closely related species. Here, we apply new sequencing technology to measure directly one mutation rate, that of base substitutions on the human Y chromosome. The Y chromosomes of two individuals separated by 13 generations were flow sorted and sequenced by Illumina (Solexa) paired-end sequencing to an average depth of 11x or 20x, respectively. Candidate mutations were further examined by capillary sequencing in cell-line and blood DNA from the donors and additional family members. Twelve mutations were confirmed in approximately 10.15 Mb; eight of these had occurred in vitro and four in vivo. The latter could be placed in different positions on the pedigree and led to a mutation-rate measurement of 3.0 x 10(-8) mutations/nucleotide/generation (95% CI: 8.9 x 10(-9)-7.0 x 10(-8)), consistent with estimates of 2.3 x 10(-8)-6.3 x 10(-8) mutations/nucleotide/generation for the same Y-chromosomal region from published human-chimpanzee comparisons depending on the generation and split times assumed.

  20. Direct tactile stimulation of dorsal occipito-temporal cortex in a visual agnosic

    OpenAIRE

    Allen, Harriet A.; Humphreys, Glyn W.

    2009-01-01

    The human occipito-temporal cortex is preferentially activated by images of objects as opposed to scrambled images [1]. Touching objects (versus textures) also activates this region [2–10]. We used neuropsychological fMRI to probe whether dorsal regions of the lateral occipital cortex (LO) are activated in tactile recognition without mediation through visual recognition. We tested a patient (HJA) with visual agnosia due to bilateral lesions of the ventral occipito-temporal cortex but spared d...

  1. A study of root canal morphology of human primary incisors and molars using cone beam computerized tomography: an in vitro study.

    Science.gov (United States)

    Gaurav, Vivek; Srivastava, Nikhil; Rana, Vivek; Adlakha, Vivek Kumar

    2013-01-01

    Variations in morphology of root canals in primary teeth usually leads to complications during and after endodontic therapy. To improve the success in endodontics, a thorough knowledge of the root canal morphology is essential. The aim of this study was to assess the variation in number and morphology of the root canals of primary incisors and molars and to study the applicability of cone beam computerized tomography (CBCT) in assessing the same. A total of 60 primary molars and incisors with full root length were collected and various parameters such as the number of roots, number of canals, diameter of root canal at cementoenamel junction and middle-third, length and angulations of roots of primary molars and incisors were studied using CBCT. The observations were put to descriptive statistics to find out the frequency, mean, standard deviation and range for all four subgroups. Further, unpaired t-test was used to compare these parameters between subgroups and analysis of variance test was implemented to evaluate the parameters within the subgroups. The CBCT showed the presence of bifurcation of root canal at middle third in 13% of mandibular incisors while 20% of mandibular molars had two canals in distal root. The diameter of distobuccal root canal of maxillary molars and mesiolingual canal of mandibular molars was found to be minimum. CBCT is a relatively new and effective technology, which provides an auxiliary imaging modality to supplement conventional radiography for assessing the variation in root canal morphology of primary teeth.

  2. On Parallel Streams through the Mouse Dorsal Lateral Geniculate Nucleus

    Directory of Open Access Journals (Sweden)

    Daniel eDenman

    2016-03-01

    Full Text Available The mouse visual system is an emerging model for the study of cortical and thalamic circuit function. To maximize the usefulness of this model system, it is important to analyze the similarities and differences between the organization of all levels of the murid visual system with other, better studied systems (e.g., non-human primates and the domestic cat. While the understanding of mouse retina and cortex has expanded rapidly, less is known about mouse dorsal lateral geniculate nucleus (dLGN. Here, we study whether parallel processing streams exist in mouse dLGN. We use a battery of stimuli that have been previously shown to successfully distinguish parallel streams in other species: electrical stimulation of the optic chiasm, contrast-reversing stationary gratings at varying spatial phase, drifting sinusoidal gratings, dense noise for receptive field reconstruction, and frozen contrast-modulating noise. As in the optic nerves of domestic cats and non-human primates, we find evidence for multiple conduction velocity groups after optic chiasm stimulation. As in so-called ‘visual mammals’, we find a subpopulation of mouse dLGN cells showing non-linear spatial summation. However, differences in stimulus selectivity and sensitivity do not provide sufficient basis for identification of clearly distinct classes of relay cells. Nevertheless, consistent with presumptively homologous status of dLGNs of all mammals, there are substantial similarities between response properties of mouse dLGN neurons and those of cats and primates.

  3. Non-destructive, preclinical evaluation of root canal anatomy of human teeth with flat-panel detector volume CT (FD-VCT); Zerstoerungsfreie praeklinische Evaluation der Wurzelkanalanatomie menschlicher Zaehne mittels Flaechendetektor-Volumen-CT (FD-VCT)

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, G.; Hassepass, F.; Dullin, C.; Grabbe, E. [Universitaetsklinikum Goettingen, Abt. Diagnostische Radiologie (Germany); Attin, T.; Hannig, C. [Universitaetsklinikum Goettingen, Abt. fuer Zahnerhaltung, Praeventive Zahnheilkunde und Paradontologie (Germany)

    2005-12-15

    Purpose: Successful endodontic diagnostics and therapy call for adequate depiction of the root canal anatomy with multimodal diagnostic imaging. The aim of the present study is to evaluate visualization of the endodont with flat-panel detector volume CT (FD-VCT). Materials and methods: 13 human teeth were examined with the prototype of a FD-VCT. After data acquisition and generation of volume data sets in volume rendering technology (VRT), the findings obtained were compared to conventional X-rays and cross-section preparations of the teeth. Results: The anatomical structures of the endodont such as root canals, side canals and communications between different root canals as well as dentricles could be detected precisely with FD-VCT. The length of curved root canals was also determined accurately. The spatial resolution of the system is around 140 {mu}m. Only around 73% of the main root canals detected with FD-VCT and 87% of the roots could be visualized with conventional dental X-rays. None of the side canals, shown with FD-VCT, was detectable on conventional X-rays. In all cases the enamel and dentin of the teeth could be well delineated. No differences in image quality could be discerned between stored and freshly extracted teeth, or between primary and adult teeth. (orig.)

  4. File list: ALL.Lar.10.AllAg.Dorsal_mesothoracic_disc [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  7. File list: ALL.Lar.20.AllAg.Dorsal_mesothoracic_disc [Chip-atlas[Archive

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  11. File list: Pol.Lar.05.AllAg.Dorsal_mesothoracic_disc [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. Dorsal ulnar cutaneous nerve conduction: reference values

    Directory of Open Access Journals (Sweden)

    Garibaldi Solange G.

    2002-01-01

    Full Text Available We investigated the reference values of the dorsal ulnar cutaneous nerve (DUC sensory nerve conduction (SNC in 66 healthy individuals. Measurements were processed using stimulating electrodes positioned between the ulnar bone and the flexor carpi ulnaris muscle, 11-13 cm proximal to the active electrode recording. Superficial recording electrodes were placed on the fourth intermetacarpal space. The mean sensory conduction velocity (SCV in males was 63.7 -- 0.16 x age ± 3.36 m/s and in females was 57.7 ± 3.37 m/s. The mean sensory nerve action potential (SNAP amplitude in males was 19.5 ± 10.7 µV and in females was 24.6 ± 5.8 µV. The mean SNAP duration was 0.96 ± 0.13 ms. No significant differences regarding the DUC-SCV, distal latency, and SNAP duration or amplitude were found between both sides of the same subject. The amplitude of the SNAP was higher in females than males. The effects of age on DUC-SCV were distinct for each gender.

  13. Event related potentials recorded in Dorsal Simultanagnosia.

    Science.gov (United States)

    Onofrj, M; Fulgente, T; Thomas, A

    1995-12-01

    Visual evoked potentials (VEPs) to central and lateral half field patterned stimuli of 1, 2 and 4 cycles per degree (cpd) were recorded in a patient with Dorsal Simultanagnosia due to bilateral lesions of parieto-occipital junction. VEPs consisted of the normal N1-P1-N2 components with same spatial frequency sensitivity as in controls. VEPs had similar latencies and amplitudes whether the patient could see or not the patterned stimuli. Event related potentials (ERPs) to visual and acoustic odd-ball paradigm were also recorded in the same patient. Visual ERPs consisted of an early NA-effect, and of N2-P3 components. P3 was recorded only from frontal, central and temporal derivations. The topographical P3 abnormality was, however, the same for visual and acoustic odd-ball paradigms. The amplitude of P3 was smaller when the patient missed visual stimuli. These findings show that severe bilateral lesions at the parieto-occipital junction, inducing Simultanagnosia, do not obliterate VEPs or ERPs components.

  14. Identification and mechanism of regulation of the zebrafish dorsal determinant.

    Science.gov (United States)

    Lu, Fu-I; Thisse, Christine; Thisse, Bernard

    2011-09-20

    In vertebrates, the animal-vegetal axis is determined during oogenesis and at ovulation, the egg is radially symmetric. In anamniotes, following fertilization, a microtubule-dependent movement leads to the displacement of maternal dorsal determinants from the vegetal pole to the future dorsal side of the embryo, providing the initial breaking of radial symmetry [Weaver C, Kimelman D (2004) Development 131:3491-3499]. These dorsal determinants induce β-catenin nuclear translocation in dorsal cells of the blastula. Previous work in amphibians has shown that secreted Wnt11/5a complexes, regulated by the Wnt antagonist Dkk-1, are required for the initiation of embryonic axis formation [Cha et al. (2009) Curr Biol 29:1573-1580]. In the current study, we determined that the vegetal maternal dorsal determinant in fish is not the Wnt11/5a complex but the canonical Wnt, Wnt8a. Translation of this mRNA and secretion of the Wnt8a protein result in a dorsal-to-ventral gradient of Wnt stimulation, extending across the entire embryo. This gradient is counterbalanced by two Wnt inhibitors, Sfrp1a and Frzb. These proteins are essential to restrict the activation of the canonical Wnt pathway to the dorsal marginal blastomeres by defining the domain where the Wnt8a activity gradient is above the threshold value necessary for triggering the canonical β-catenin pathway. In summary, this study establishes that the zebrafish maternal dorsal determinant, Wnt8a, is required to localize the primary dorsal center, and that the extent of this domain is defined by the activity of two maternally provided Wnt antagonists, Sfrp1a and Frzb.

  15. Clinically relevant concentration of pregabalin has no acute inhibitory effect on excitation of dorsal horn neurons under normal or neuropathic pain conditions: An intracellular calcium-imaging study in spinal cord slices from adult rats.

    Science.gov (United States)

    Baba, Hiroshi; Petrenko, Andrey B; Fujiwara, Naoshi

    2016-10-01

    Pregabalin is thought to exert its therapeutic effect in neuropathic pain via binding to α2δ-1 subunits of voltage-gated calcium (Ca(2+)) channels. However, the exact analgesic mechanism after its binding to α2δ-1 subunits remains largely unknown. Whether a clinical concentration of pregabalin (≈10μM) can cause acute inhibition of dorsal horn neurons in the spinal cord is controversial. To address this issue, we undertook intracellular Ca(2+)-imaging studies using spinal cord slices with an intact attached L5 dorsal root, and examined if pregabalin acutely inhibits the primary afferent stimulation-evoked excitation of dorsal horn neurons in normal rats and in rats with streptozotocin-induced painful diabetic neuropathy. Under normal conditions, stimulation of a dorsal root evoked Ca(2+) signals predominantly in the superficial dorsal horn. Clinically relevant (10μM) and a very high concentration of pregabalin (100μM) did not affect the intensity or spread of dorsal root stimulation-evoked Ca(2+) signals, whereas an extremely high dose of pregabalin (300μM) slightly but significantly attenuated Ca(2+) signals in normal rats and in diabetic neuropathic (DN) rats. There was no difference between normal rats and DN rats with regard to the extent of signal attenuation at all concentrations tested. These results suggest that the activity of dorsal horn neurons in the spinal cord is not inhibited acutely by clinical doses of pregabalin under normal or DN conditions. It is very unlikely that an acute inhibitory action in the dorsal horn is the main analgesic mechanism of pregabalin in neuropathic pain states. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. SPINAL DEFORMITIES AFTER SELECTIVE DORSAL RHIZOTOMY

    Directory of Open Access Journals (Sweden)

    PATRICIO PABLO MANZONE

    Full Text Available ABSTRACT Objective: Selective dorsal rhizotomy (SDR used for spasticity treatment could worsen or develop spinal deformities. Our goal is to describe spinal deformities seen in patients with cerebral palsy (CP after being treated by SDR. Methods: Retrospective study of patients operated on (SDR between January/1999 and June/2012. Inclusion criteria: spinal Rx before SDR surgery, spinography, and assessment at follow-up. We evaluated several factors emphasizing level and type of SDR approach, spinal deformity and its treatment, final Risser, and follow-up duration. Results: We found 7 patients (6 males: mean age at SDR 7.56 years (4.08-11.16. Mean follow-up: 6.64 years (2.16-13, final age: 14.32 years (7.5-19. No patient had previous deformity. GMFCS: 2 patients level IV, 2 level III, 3 level II. Initial walking status: 2 community walkers, 2 household walkers, 2 functional walkers, 1 not ambulant, at the follow-up, 3 patients improved, and 4 kept their status. We found 4 TL/L laminotomies, 2 L/LS laminectomies, and 1 thoracic laminectomy. Six spinal deformities were observed: 2 sagittal, 3 mixed, and 1 scoliosis. There was no association among the type of deformity, final gait status, topographic type, GMFCS, age, or SDR approach. Three patients had surgery indication for spinal deformity at skeletal maturity, while those patients with smaller deformities were still immature (Risser 0 to 2/3 although with progressive curves. Conclusions: After SDR, patients should be periodically evaluated until they reach Risser 5. The development of a deformity does not compromise functional results but adds morbidity because it may require surgical treatment.

  17. Effects of Tatariside G Isolated from Fagopyrum tataricum Roots on Apoptosis in Human Cervical Cancer HeLa Cells

    Directory of Open Access Journals (Sweden)

    Yuan Li

    2014-07-01

    Full Text Available Cervical cancer is the second most common female carcinoma. Current therapies are often unsatisfactory, especially for advanced stage patients. The aim of this study was to explore the effects of tatariside G (TG on apoptosis in human cervical cancer HeLa cells and the possible mechanism of action involved. An MTT assay was employed to evaluate cell viability. Hoechst 33258 staining and flow cytometry (FCM assays were used to detect cell apoptosis. The protein expression of phosphorylated JNK, P38, ERK and Akt and cleaved caspase-3 and caspase-9 was evaluated by western blot analysis. Additionally, the mRNA expression of caspase-3 and caspase-9 was measured by fluorescent quantitative reverse transcription-PCR (FQ-RT-PCR. TG notably inhibited cell viability, enhanced the percentage of apoptotic cells, facilitated the phosphorylation of p38 MAPK and JNK proteins and caspase-3 and caspase-9 cracking, downregulated the phosphorylation level of Akt, and increased the loss of MMP and the mRNA expression of caspase-3 and caspase-9. TG-induced apoptosis is associated with activation of the mitochondrial death pathway. TG may be an effective candidate for chemotherapy against cervical cancer.

  18. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength

    OpenAIRE

    Rippe, Marília Pivetta [UNESP; Manuela Favarin SANTINI; Bier, Carlos Alexandre Souza; BALDISSARA, Paolo; VALANDRO, Luiz Felipe

    2014-01-01

    Objective: To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. Material and Methods: eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments), the type of intraradicular post (fiber posts- FRC and cast post and core- CPC) and the use of mechanical cycling (MC) as follows: Manual and FRC; Manual, FRC and MC; Man...

  19. Semiconductor laser irradiation improves root canal sealing during routine root canal therapy

    OpenAIRE

    Su, Dandan; Hu, Xingxue; Wang, Dashan; Cui, Ting; Yao, RuYong; Sun, Huibin

    2017-01-01

    Objective To evaluate the effect of semiconductor laser irradiation on root canal sealing after routine root canal therapy (RCT). Methods Sixty freshly extracted single-rooted human teeth were randomly divided into six groups (n = 10). The anatomic crowns were sectioned at the cementoenamel junction and the remaining roots were prepared endodontically with conventional RCT methods. Groups A and B were irradiated with semiconductor laser at 1W for 20 seconds; Groups C and D were ultrasonically...

  20. A study of root canal morphology of human primary incisors and molars using cone beam computerized tomography: An in vitro study

    Directory of Open Access Journals (Sweden)

    Vivek Gaurav

    2013-01-01

    Full Text Available Background: Variations in morphology of root canals in primary teeth usually leads to complications during and after endodontic therapy. To improve the success in endodontics, a thorough knowledge of the root canal morphology is essential. Aim: The aim of this study was to assess the variation in number and morphology of the root canals of primary incisors and molars and to study the applicability of cone beam computerized tomography (CBCT in assessing the same. Settings and Design: A total of 60 primary molars and incisors with full root length were collected and various parameters such as the number of roots, number of canals, diameter of root canal at cementoenamel junction and middle-third, length and angulations of roots of primary molars and incisors were studied using CBCT. Statistical analysis used: The observations were put to descriptive statistics to find out the frequency, mean, standard deviation and range for all four subgroups. Further, unpaired t-test was used to compare these parameters between subgroups and analysis of variance test was implemented to evaluate the parameters within the subgroups. Results and Conclusion: The CBCT showed the presence of bifurcation of root canal at middle third in 13% of mandibular incisors while 20% of mandibular molars had two canals in distal root. The diameter of distobuccal root canal of maxillary molars and mesiolingual canal of mandibular molars was found to be minimum. CBCT is a relatively new and effective technology, which provides an auxiliary imaging modality to supplement conventional radiography for assessing the variation in root canal morphology of primary teeth.

  1. [Dorsal capsulodesis for the treatment of scapholunate instability].

    Science.gov (United States)

    Stephan, Christine; Prommersberger, Karl-Josef; van Schoonhoven, Jörg

    2009-11-01

    To regain stability of the proximal carpal row after scapholunate ligament rupture in order to avoid osteoarthritis and carpal collapse. As additional therapy in scapholunate ligament repair especially in patients with static, but reducible scapholunate malalignment. Fixed scapholunate malalignment. Osteoarthritis of the radiocarpal or the midcarpal joint. Dorsal approach to the carpal joint with release of the second, third and fourth extensor compartment and resection of the dorsal interosseous nerve. Opening of the radiocarpal joint for inspection of the chondral surfaces and the scapholunate ligament for possible repair. If needed, reduction of scaphoid and lunate. Repair of the scapholunate ligament. If a reduction of scaphoid and lunate is necessary, temporary Kirschner wire fixation of the scaphoid to the capitate and the lunate. The dorsal intercarpal ligament is identified and its middle third is dissected and elevated from the triquetrum remaining attached to the distal scaphoid pole. The ulnar end of the elevated part of the dorsal intercarpal ligament is pulled through a split in the dorsal radiotriquetral ligament and fixed to itself. Closure of the proximal and distal third of the dorsal intercarpal ligament. Management Immobilization in a below-elbow cast including the metacarpophalangeal joint of the thumb for 6 weeks. Removal of the Kirschner wires, if used, 8 weeks postoperatively. Physiotherapy to improve wrist motion. Most of the reports in the literature show an improvement of pain. The effect on radiologic parameters and the development of osteoarthritis remains uncertain.

  2. Functional connectivity of the dorsal striatum in female musicians

    Directory of Open Access Journals (Sweden)

    Shoji eTanaka

    2016-04-01

    Full Text Available The dorsal striatum (caudate/putamen is a node of the cortico-striato-pallido-thalamo-cortical (CSPTC motor circuit, which plays a central role in skilled motor learning, a critical feature of musical performance. The dorsal striatum receives input from a large part of the cerebral cortex, forming a hub in the cortical-subcortical network. This study sought to examine how the functional network of the dorsal striatum differs between musicians and nonmusicians.Resting state functional magnetic resonance imaging (fMRI data were acquired from female university students majoring in music and nonmusic disciplines. The data were subjected to graph theoretical analysis and functional connectivity analysis. The graph theoretical analysis of the entire brain revealed that the degree, which represents the number of connections, of the bilateral putamen was significantly lower in musicians than in nonmusicians. The functional connectivity analysis indicated that compared with nonmusicians, musicians had significantly decreased connectivity between the left putamen and bilateral frontal operculum and between the left caudate nucleus and cerebellum. In conclusion, compared with nonmusicians, female musicians have a sma