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Sample records for human intervertebral disk

  1. HISTOLOGICAL MARKERS OF DEGENERATION AND REGENERATION OF THE HUMAN INTERVERTEBRAL DISK

    OpenAIRE

    PELETTI-FIGUEIRÓ, MANUELA; AGUIAR, ISRAEL SILVEIRA DE; PAESI, SUELEN; MACHADO, DENISE CANTARELLI; ECHEVERRIGARAY, SERGIO; ROESCH-ELY, MARIANA; FALAVIGNA, ASDRUBAL; HENRIQUES, JOÃO ANTONIO PÊGAS

    2017-01-01

    ABSTRACT Objective: To define histological scores for intervertebral disc degeneration that would enable the definition of morphological characteristics of disease, besides improving knowledge of the lumbar degenerative disc disease by means of immunohistochemical markers. Methods: Hematoxylin and Eosin, Alcian/PAS, Masson Trichrome and Safranin O/FCF staining was used on the intervertebral disc degeneration sections of patients with lumbar degenerative disc disease. The protein markers d...

  2. Experimental Model of Intervertebral Disk Mediated Postoperative Epidural Fibrosis.

    Science.gov (United States)

    Larionov, Sergey N; Sorokovikov, V A; Erdyneyev, K C; Lepekhova, S A; Goldberg, O A

    2016-07-01

    Postoperative epidural fibrosis (EF) after lumbar discectomy is the most common and at the same time controversial issue. The etiology and pathogenesis creates a lot of discussion and selection of methods of treatment and prevention continues. LIV laminectomy with dura mater (DM) exposition was done in 24 rats, and then, 0.3 ml of elements of suspension of autologous intervertebral disk was implicated on DM. As autologous intervertebral disk, we used the intervertebral disk from amputated tail. In all the animals, incisions were closed with 3/0 Vicryl. EF was examined. Fibroblast cell density was calculated in each field at ×40 magnification: Grade 1 - fewer than 100 fibroblasts in each field; Grade 2 - 100-150 fibroblasts in each field; Grade 3 - more than 150 fibroblasts in each field. Based on histological results, we confirmed our model of experiment. On the 30th day of evaluation, there were significant histological evidences of postoperative epidural adhesions in experimental animals, which included the obliteration of epidural space, the presence of adhesions in the dura and nerve roots, the restructuring of the yellow ligament, bone sclerosis, excessive appearance of fibrous tissue around the autologous intervertebral disk tissue that applied on the DM. In our work, we describe a new experimental model, where the elements of autologous intervertebral disk play the role of inflammation trigger, which cause postoperative scar and EF.

  3. Concept Development of a New Lumbar Intervertebral Disk Implant

    Directory of Open Access Journals (Sweden)

    Doicin Cristian-Vasile

    2017-01-01

    Full Text Available Worldwide spinal cord injury incidence is rising, due to spikes in traffic incidences, violence and an increase in ageing population, prone to injuries. To satisfy an expanding market, a wide variety of spinal implantable devices are available. The current study develops a new concept for a lumbar intervertebral disk implant which addresses the disadvantages of current commercialised devices. The proposed intervertebral disk implant concept limits the anatomical movements of the trunk, replicating the functions of a natural intervertebral disk. Three concept variations were designed and evaluated using FEA simulations for three main operating hypotheses: Compression of vertebrae in normal up-right position; Lifting weights at a correct and at an incorrect angle; Shock in the lumbar region. Von Misses stress, URES: Resultant Displacement and ESTRN: Equivalent Strain studies were used to evaluate the capability of the intervertebral disk implant concept to withstand the design load. Concept 3 failed URES and ESTRN simulations for the hypotheses which involved lifting weights and delivering a shock in the lumbar region. Simulation revealed optimum results for Concept 1, which was selected for further research.

  4. Correlation between T2 relaxation time and intervertebral disk degeneration

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    Takashima, Hiroyuki; Takebayashi, Tsuneo; Yoshimoto, Mitsunori; Terashima, Yoshinori; Tsuda, Hajime; Ida, Kazunori; Yamashita, Toshihiko [Sapporo Medical University, Department of Orthopedic Surgery, School of Medicine, Sapporo, Hokkaido (Japan)

    2012-02-15

    Magnetic resonance T2 mapping allows for the quantification of water and proteoglycan content within tissues and can be used to detect early cartilage abnormalities as well as to track the response to therapy. The goal of the present study was to use T2 mapping to quantify intervertebral disk water content according to the Pfirrmann classification. This study involved 60 subjects who underwent lumbar magnetic resonance imaging (a total of 300 lumbar disks). The degree of disk degeneration was assessed in the midsagittal section on T2-weighted images according to the Pfirrmann classification (grades I to V). Receiver operating characteristic (ROC) analysis was performed among grades to determine the cut-off values. In the nucleus pulposus, T2 values tended to decrease with increasing grade, and there was a significant difference in T2 values between each grade from grades I to IV. However, there was no significant difference in T2 values in the anterior or posterior annulus fibrosus. T2 values according to disk degeneration level classification were as follows: grade I (>116.8 ms), grade II (92.7-116.7 ms), grade III (72.1-92.6 ms), grade IV (<72.0 ms). T2 values decreased with increasing Pfirrmann classification grade in the nucleus pulposus, likely reflecting a decrease in proteoglycan and water content. Thus, T2 value-based measurements of intervertebral disk water content may be useful for future clinical research on degenerative disk diseases. (orig.)

  5. CLINICAL AND MAGNETIC RESONANCE IMAGING CHARACTERISTICS OF THORACOLUMBAR INTERVERTEBRAL DISK EXTRUSIONS AND PROTRUSIONS IN LARGE BREED DOGS.

    Science.gov (United States)

    Gomes, Sergio A; Volk, Holger A; Packer, Rowena Ma; Kenny, Patrick J; Beltran, Elsa; De Decker, Steven

    2016-07-01

    Treatment recommendations differ for dogs with intervertebral disk extrusion vs. intervertebral disk protrusion. The aim of this retrospective, cross-sectional study was to determine whether clinical and magnetic resonance imaging (MRI) variables could be used to predict a diagnosis of thoracolumbar intervertebral disk extrusion or protrusion in dogs. Dogs were included if they were large breed dogs, had an MRI study of the thoracolumbar or lumbar vertebral column, had undergone spinal surgery, and had the type of intervertebral disk herniation (intervertebral disk extrusion or protrusion) clearly stated in surgical reports. A veterinary neurologist unaware of surgical findings reviewed MRI studies and recorded number, location, degree of degeneration and morphology of intervertebral disks, presence of nuclear clefts, disk space narrowing, extent, localization and lateralization of herniated disk material, degree of spinal cord compression, intraparenchymal intensity changes, spondylosis deformans, spinal cord swelling, spinal cord atrophy, vertebral endplate changes, and presence of extradural hemorrhage. Ninety-five dogs were included in the sample. Multivariable statistical models indicated that longer duration of clinical signs (P = 0.01), midline instead of lateralized disk herniation (P = 0.007), and partial instead of complete disk degeneration (P = 0.01) were associated with a diagnosis of intervertebral disk protrusion. The presence of a single intervertebral herniation (P = 0.023) and dispersed intervertebral disk material not confined to the disk space (P = 0.06) made a diagnosis of intervertebral disk extrusion more likely. Findings from this study identified one clinical and four MRI variables that could potentially facilitate differentiating intervertebral disk extrusions from protrusions in dogs. © 2016 American College of Veterinary Radiology.

  6. RNA sequencing identifies gene regulatory networks controlling extracellular matrix synthesis in intervertebral disk tissues.

    Science.gov (United States)

    Riester, Scott M; Lin, Yang; Wang, Wei; Cong, Lin; Mohamed Ali, Abdel-Moneim; Peck, Sun H; Smith, Lachlan J; Currier, Bradford L; Clark, Michelle; Huddleston, Paul; Krauss, William; Yaszemski, Michael J; Morrey, Mark E; Abdel, Matthew P; Bydon, Mohamad; Qu, Wenchun; Larson, Annalise N; van Wijnen, Andre J; Nassr, Ahmad

    2017-12-11

    Degenerative disk disease of the spine is a major cause of back pain and disability. Optimization of regenerative medical therapies for degenerative disk disease requires a deep mechanistic understanding of the factors controlling the structural integrity of spinal tissues. In this investigation, we sought to identify candidate regulatory genes controlling extracellular matrix synthesis in spinal tissues. To achieve this goal we performed high throughput next generation RNA sequencing on 39 annulus fibrosus and 21 nucleus pulposus human tissue samples. Specimens were collected from patients undergoing surgical discectomy for the treatment of degenerative disk disease. Our studies identified associations between extracellular matrix genes, growth factors, and other important regulatory molecules. The fibrous matrix characteristic of annulus fibrosus was associated with expression of the growth factors platelet derived growth factor beta (PDGFB), vascular endothelial growth factor C (VEGFC), and fibroblast growth factor 9 (FGF9). Additionally we observed high expression of multiple signaling proteins involved in the NOTCH and WNT signaling cascades. Nucleus pulposus extracellular matrix related genes were associated with the expression of numerous diffusible growth factors largely associated with the transforming growth signaling cascade, including transforming factor alpha (TGFA), inhibin alpha (INHA), inhibin beta A (INHBA), bone morphogenetic proteins (BMP2, BMP6), and others. this investigation provides important data on extracellular matrix gene regulatory networks in disk tissues. This information can be used to optimize pharmacologic, stem cell, and tissue engineering strategies for regeneration of the intervertebral disk and the treatment of back pain. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  7. Lumbar myelography in the diagnosis of thoracolumbar intervertebral disk extrusion in dogs: prospective study

    OpenAIRE

    Paulo Vinicius Tertuliano Marinho; Bruno Watanabe Minto; Carolina Camargo Zani; Érica Siqueira de Souza; Nathália Helena Pereira da Silva Dal Pietro; João Augusto Leonel de Souza; Júlio Carlos Canola; Andrigo Barboza De Nardi

    2014-01-01

    Thoracolumbar disk extrusion is the most common cause of extradural compression of the spinal cord in dogs. Myelography is one of the most commonly performed techniques for the diagnosis of this affection. This study aimed to evaluate the applicability and effectiveness of lumbar myelography in the diagnosis of thoracolumbar intervertebral disk extrusion in dogs, as well as its major complications. Twenty dogs were used in this study. Animals were included when neurological examination sugges...

  8. Incidence of intervertebral disk degeneration-related diseases and associated mortality rates in dogs

    NARCIS (Netherlands)

    Bergknut, N.|info:eu-repo/dai/nl/314418059; Egenvall, A.; Hagman, R.; Gustas, P.; Hazewinkel, H.A.W.|info:eu-repo/dai/nl/070975760; Meij, B.P.|info:eu-repo/dai/nl/164045805; Lagerstedt, A.S.

    2012-01-01

    Abstract Journal of the American Veterinary Medical Association June 1, 2012, Vol. 240, No. 11, Pages 1300-1309 doi: 10.2460/javma.240.11.1300 Incidence of intervertebral disk degeneration–related diseases and associated mortality rates in dogs Niklas Bergknut, Dr med vet, PhD; Agneta Egenvall, Dr

  9. Lumbar intervertebral disk degeneration in elite competitive swimmers: a case control study.

    Science.gov (United States)

    Kaneoka, Koji; Shimizu, Ken; Hangai, Mika; Okuwaki, Toru; Mamizuka, Naotaka; Sakane, Masataka; Ochiai, Naoyuki

    2007-08-01

    The majority of orthopaedic problems experienced by competitive swimmers are related to pain in the shoulder, low back, and knee. Three of 39 national swim team members were hampered in their performance due to lumbar disk herniation at an international competition in 2001. There has been no previous research into lumbar disk degeneration in elite competitive swimmers. Excessive competitive swimming activities accelerate lumbar disk degeneration. Case control study; Level of evidence, 3. Fifty-six elite swimmers (high-load group, 35 men and 21 women; mean age, 19.6 years) and a control group of 38 university recreational level swimmers (low-load group, 24 men and 14 women; mean age, 21.1 years) were evaluated for lumbar disk degeneration using magnetic resonance imaging. We compared the prevalence of disk degeneration and the disk level between the 2 groups and further investigated the relationship among their symptoms, swimming styles, and disk degeneration. Thirty-eight (68%) elite swimmers and 11 (29%) controls had degenerated disks at various disk levels, and the prevalence was significantly greater in the elite swimmers (P = .0002). Comparison between the 2 groups of the prevalence of disk degeneration at each level revealed that the disk level of L5-S1 was significantly more frequently degenerated in the high-load group (P = .026). There was no significant relationship observed among the variables of low back pain symptoms, swimming strokes, and disk degeneration. Excessive competitive swimming activities might exaggerate lumbar intervertebral disk degeneration, especially in the L5-S1 intervertebral segment.

  10. Treatment and outcome of herniated lumbar intervertebral disk in a ...

    African Journals Online (AJOL)

    The goal of treatment in cases of lumbar disk herniation is to return the patient to normal activities as quickly as possible. Therefore unnecessary surgery should be avoided (2). However about 10% of patients with lumbar disk herniation will ultimately require surgery (3). Surgery is recommended if the sciatica is severe and ...

  11. Transdural epidurography in the diagnosis of lesions of the lumbar intervertebral disks

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    Matvienko, V.I.; Serikov, Yu.G.; Syuremov, M.N. (Rostovskij-na-Donu Meditsinskij Inst. (USSR))

    The anterior epidural space adjoining directly the posterior parts of the vertebral bodies, was examined with 8-12% solution of verografin in 140 patients with lumbar osteochodrosis. Of them 110 had been previously operated on. The use of low-concentration water-soluble iodine contrast agents makes it possible to avoid the stimulation of the epidural structures. X-ray appearance which is typical of protrusion and hernia of the intervertebral disks is described.

  12. RESULTS OF TOTAL LUMBAR INTERVERTEBRAL DISK REPLACEMENT WITH M6-L: A MULTICENTER STUDY

    OpenAIRE

    Byvaltsev, Vadim Anatol’evich; Kalinin, Andrei Andreevich; Stepanov, Ivan Andreevich; Pestryakov, Yuri Yakovlevich; Shepelev, Valeriy Vladimirovich

    2017-01-01

    ABSTRACT Objective: In this paper we report the clinical and radiological results of lumbar intervertebral disk (IVD) replacement with M6-L for the treatment of patients with IVD degeneration. Methods: One hundred and fifty-six patients with IVD degeneration were operated with the one level implantation of an M6-L prosthesis at three neurosurgical departments, in Irkutsk, Krasnoyarsk and Vladivostok. We assessed pain intensity (VAS), the Oswestry disability index (ODI) and outcomes by the Mac...

  13. THE INTERVERTEBRAL DISK PROTHESIS INSTALLATION AFTER ABLATION OF A DISK‘S HERNIA AT CERVICAL LEVEL

    Directory of Open Access Journals (Sweden)

    I.A.Norkin

    2008-12-01

    Full Text Available The purpose ofthe present work was to study the possibility of use the artificial disk «PRODISK» at cervical level after ablation of intervertebraldisk’s hernia. The basis of this research is complexexamination and surgical treatment of a 52-years-old-woman with osteochondrosis of cervical spine and with radiculopathy syndrome because of compression of spinal hernia roots of intervertebral disk On May, 29th, 2007 the patientwas operated: «diskectomyC6-C7' disk’s hernia removal, implantation of an artificial disk« PRODISK»at the level C6- C7». The patient became active on the third day after the operation, and she was discharged in eight days. Her neurologic symptoms regressed completely. Range of cervical motions was in the normal condition (flexia/anteflexia-35 °-40 °. The pain syndrome was arrested (VAS-2, VRS-1. We consider that any operation causes disorder of structural and functional properties and requires prosthetics of intervertebral disk’s, which can fully reconstruct biomechanical qualities of the operated segment

  14. Diagnosis of hernia of lumbar intervertebral disk. Potentials and limits of MR imaging

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    Beyer, H.K.; Uhlenbrock, D.; Steiner, G.

    1986-04-01

    CT and myelography are acknowledged techniques for the detection and diagnosis of hernia of intervertebral disk. After the development and successful testing of special surface coils, MR imaging is a serious competitor of the two methods, offering advantages such as absence of ionizing radiation, or any other hazard, possibility of making tomograms in various planes, the sagittal plane being preferably used. Spatial resolution of CT and MRI is about equal, but the contrast resolution of MRI is far better. The contribution in hand is the first communication of results of a comparative study.

  15. High signal intensity of intervertebral calcified disks on T1-weighted MR images resulting from fat content

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    Malghem, Jacques; Lecouvet, Frederic E.; Berg, Bruno C. Vande; Duprez, Thierry; Cosnard, Guy; Maldague, Baudouin E. [Universite Catholique de Louvain, Cliniques Universitaires St. Luc, Brussels (Belgium); Francois, Robert [Belgian Military Hospital, Department of Rheumatology, Brussels (Belgium)

    2005-02-01

    To explain a cause of high signal intensity on T1-weighted MR images in calcified intervertebral disks associated with spinal fusion. Magnetic resonance and radiological examinations of 13 patients were reviewed, presenting one or several intervertebral disks showing a high signal intensity on T1-weighted MR images, associated both with the presence of calcifications in the disks and with peripheral fusion of the corresponding spinal segments. Fusion was due to ligament ossifications (n=8), ankylosing spondylitis (n=4), or posterior arthrodesis (n=1). Imaging files included X-rays and T1-weighted MR images in all cases, T2-weighted MR images in 12 cases, MR images with fat signal suppression in 7 cases, and a CT scan in 1 case. Histological study of a calcified disk from an anatomical specimen of an ankylosed lumbar spine resulting from ankylosing spondylitis was examined. The signal intensity of the disks was similar to that of the bone marrow or of perivertebral fat both on T1-weighted MR images and on all sequences, including those with fat signal suppression. In one of these disks, a strongly negative absorption coefficient was focally measured by CT scan, suggesting a fatty content. The histological examination of the ankylosed calcified disk revealed the presence of well-differentiated bone tissue and fatty marrow within the disk. The high signal intensity of some calcified intervertebral disks on T1-weighted MR images can result from the presence of fatty marrow, probably related to a disk ossification process in ankylosed spines. (orig.)

  16. Quantification of the association between intervertebral disk calcification and disk herniation in Dachshunds

    DEFF Research Database (Denmark)

    Jensen, Vibeke Frøkjær; Beck, S.; Christensen, K.A.

    2008-01-01

    -seven of the dogs had survived to the time of the present study and were >= 8 years of age; 24 others had not survived. Procedures-Radiographic examination of 36 surviving dogs was performed, and information on occurrence of disk calcification at 2 years of age were obtained from records of all 61 Dachshunds...

  17. Clinical characterization of thoracolumbar and lumbar intervertebral disk extrusions in English Cocker Spaniels.

    Science.gov (United States)

    Cardy, Thomas J A; Tzounos, Caitlin E; Volk, Holger A; De Decker, Steven

    2016-02-15

    To assess the anatomic distribution of thoracolumbar and lumbar intervertebral disk extrusions (IVDEs) in English Cocker Spaniels as compared with findings in Dachshunds and to characterize clinical findings in English Cocker Spaniels with thoracolumbar or lumbar IVDEs affecting various regions of the vertebral column. Retrospective observational study. 81 English Cocker Spaniels and 81 Dachshunds with IVDEs. Signalment, clinical signs, neurologic examination findings, and affected intervertebral disk spaces (IVDSs) were recorded for both breeds. Management methods and outcomes were recorded for English Cocker Spaniels. Lesions were categorized as thoracolumbar (IVDSs T9-10 through L1-2), midlumbar (L2-3 through L4-5), or caudal lumbar (L5-6 through L7-S1). Midlumbar and caudal lumbar IVDEs were significantly more common in English Cocker Spaniels than in Dachshunds. English Cocker Spaniels with caudal lumbar IVDEs had a longer median duration of clinical signs before evaluation and more commonly had unilateral pelvic limb lameness or spinal hyperesthesia as the predominant clinical sign than did those with IVDEs at other sites. Those with caudal lumbar IVDEs less commonly had neurologic deficits and had a higher median neurologic grade (indicating lesser severity), shorter mean postoperative hospitalization time, and faster mean time to ambulation after surgery than those with other sites affected. These variables did not differ between English Cocker Spaniels with thoracolumbar and midlumbar IVDEs. Caudal and midlumbar IVDEs were more common in English Cocker Spaniels than in Dachshunds. English Cocker Spaniels with caudal lumbar IVDE had clinical signs and posttreatment responses that differed from those in dogs with midlumbar or thoracolumbar IVDE.

  18. Hygroviscoelasticity of the Human Intervertebral Disc.

    Science.gov (United States)

    1980-07-01

    the intervertebral disc (Figures 2(a) and 2(b)). -7- 7 CERVICAL CURVE (C1 -C7 (CERVICAL LORDOSIS CURVE) THORACIC CURVE (T I- T12) $ (DORSAL KYPHOSIS ...CURVE) LUMBAR CURVE (L 1-1.5 ) (LUMBAR LORDOSIS CURVE) PELVIC CURVE (SACRUM) COCCYX FIGURE 1 Lateral View of Vertebral Column *1 -8- POSTERIOR

  19. Collagen crosslinks in human lumbar intervertebral disc aging.

    Science.gov (United States)

    Pokharna, H K; Phillips, F M

    1998-08-01

    Human lumbar intervertebral discs from individuals of varying ages were obtained at autopsy and analyzed for collagen crosslinks. To analyze alterations in collagen crosslinks in human lumbar intervertebral discs with aging and disc degeneration. Crosslinks studied were pyridinoline, which is a collagen maturation crosslink, and pentosidine, a nonenzymatically initiated age-related crosslink. Crosslinking of collagen fibers within the matrix affects intervertebral disc biomechanics. In various connective tissues, alterations in pyridinoline and pentosidine crosslinks have been shown to predispose the tissue to mechanical failure. Little is known about the fate of intervertebral disc collagen crosslinks with advancing age and disc degeneration. Forty-two postmortem lumbar intervertebral discs were harvested from nine individuals whose ages were 24, 44, 47, 52, 67, 72, 75, 82, and 89 years. Degree of disc degeneration was graded macroscopically. Each lumbar disc was extracted with 4 mol/L guanidine hydrochloride, and the residual collagen was acid hydrolyzed and analyzed by reverse-phase high-performance liquid chromatography for pyridinoline and pentosidine crosslinks. The findings indicate a decrease in pyridinoline and an increase in pentosidine crosslink levels with disc aging. The decrease in pyridinoline crosslinks with disc aging is a novel finding and may have detrimental effects on matrix resilience. Increased pentosidine levels have been implicated in the age-related deterioration of connective tissue. With advancing degrees of macroscopic disc degeneration, pentosidine levels increase, and pyridinoline levels are diminished. Alterations in concentrations of pyridinoline and pentosidine collagen crosslinks occur with intervertebral disc aging and degeneration. These changes may contribute to the loss of disc integrity and play a role in the pathogenesis of the degenerative process.

  20. [The possibilities for diagnostics of prescription of death coming based on the changes in the lumbar intervertebral disks (the comparison of the morphological, immunohistochemical and topographical findings)].

    Science.gov (United States)

    Byval'tsev, V A; Stepanov, I A; Semenov, A V; Perfil'ev, D V; Belykh, E G; Bardonova, L A; Nikiforov, S B; Sudakov, N P; Bespyatykh, I V; Antipina, S L

    2017-01-01

    The objective of the present study was the comprehensive analysis of the postmortem changes in the lumbar intervertebral disks within different periods after death. A total of seven vertebromotor segments were distinguished in the lumbosacral region of the vertebral column based on the examination of 7 corpses. All these segments were divided into three groups in accordance with the prescription of death coming as follows: up to 12 hours (group 1), between 12 and 24 hours (group 2), and between 24 and 36 hours (group 3) after death. The models of the segments thus obtained were subjected to the study by means of diffusion weighted MRI. The removed intervertebral disks were used for morphological and immunohistochemical investigations. The comparison of the diffusion coefficients (DI) revealed the significant difference between the intervertebral disks assigned to groups 1 and 2 (pcore, the vertebral end plate, and the fibrous ring in all the above groups of the intervertebral disks was significantly reduced (p<0.01). The analysis of the correlation dependence between cell density and diffusion coefficients has demonstrated the well apparent relationship between these characteristics of the intervertebral disks comprising groups 1 and 2. It is concluded that diffusion weighted MRI in the combination with the calculation of diffusion coefficients for the intervertebral disks provides a tool for diagnostics of prescription of death coming as confirmed by the results of the morphometric studies and immunohistochemical analysis.

  1. Validation of genome-wide intervertebral disk calcification associations in Dachshund and further investigation of the chromosome 12 susceptibility locus

    DEFF Research Database (Denmark)

    Ryt-Hansen, Mette Egesborg; Scheibye-Alsing, Karsten; Karlskov-Mortensen, Peter

    2012-01-01

    Herniation of the intervertebral disk is a common cause of neurological dysfunction in the dog, particularly in the Dachshund. Using the Illumina CanineHD BeadChip, we have previously identified a major locus on canine chromosome 12 nucleotide positions 36,750,205-38,524,449 that strongly......(s) are most likely to be found between nucleotide 36,750,205-37,494,845 as this region explains the highest proportion of variance in the dataset. Finally, we develop a risk prediction model for wire-haired Dachshunds. We validated the association of the chromosome 12 locus with disk calcification...

  2. Recurrence of disk herniation following percutaneous laser disk ablation in dogs with a history of thoracolumbar intervertebral disk herniation: 303 cases (1994-2011).

    Science.gov (United States)

    Dugat, Danielle R; Bartels, Kenneth E; Payton, Mark E

    2016-12-15

    OBJECTIVE To determine rate of recurrence of disk herniation in dogs that underwent percutaneous laser disk ablation (PLDA) because of a previous episode of suspected or confirmed thoracolumbar intervertebral disk herniation (IVDH). DESIGN Retrospective case series. ANIMALS 303 dogs that underwent PLDA and for which a minimum of 3 years of follow-up information was available (n = 294) or for which recurrence was documented within 3 years after the procedure (9). PROCEDURES Information on signalment, previous episodes of IVDH, specifics of the PLDA procedure, and recurrence was obtained from the medical records. Owners were contacted to complete a questionnaire regarding outcome and recurrence. RESULTS 60 of the 303 (19.8%) dogs had an episode of suspected or confirmed IVDH after undergoing PLDA, but only 11 of the 303 (3.6%) dogs had a recurrence of IVDH confirmed by means of CT or MRI and hemilaminectomy. Recurrence rate following PLDA was not significantly different between dogs that had been treated medically for previous episodes of IVDH and dogs that had been treated surgically. Overall, 270 of 286 (94.4%) owners reported that their dog was the same (109 [38.1%]) or improved (161 [56.3%]) immediately after PLDA, and 265 (92.7%) owners rated their satisfaction with the procedure as ≥ 9 on a scale from 1 (completely dissatisfied) to 10 (completely satisfied). CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that PLDA was a relatively safe, minimally invasive procedure associated with a low rate of recurrence of disk herniation when performed in dogs with a history of previous episodes of suspected or confirmed IVDH.

  3. CT of the lumbar spine after operation of the intervertebral disks. Pt. 2

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    Schindler, G.; Klott, K.

    1984-03-01

    Differentiation between prolapse recidivation and scar tissue is the central problem in spinal diagnostics after operation of the intervertebral disks. Detailed information on the surgical procedure and on the most recent clinical findings is indispensable. Thin layers of 2 mm should have 2 mm feed, 5 mm layers require an overlapping feed of 3 mm. The planigraphic planes should be parallel to the corresponding bottom and cover plates. Secondary prolapse in non-operated segments is easily identified by looking at the segments, while prolapse recidivation is difficult to distinguish from scar tissue. The prolapse has a higher density (90 to 120 HU as against 50 to 75 HU in scar tissue). Also, the prolapse is located on the ventral side; it is arched, of regular shape, and displaces the dural bag. The scar is located in the surgical access; it is irregular, surrounding the dural bag and the spinal nerves, and tends to cause traction. Differentiation via contrast enhancement of scar tissue is only possible in very recent scars.

  4. Computer modelling of the mechanical behaviour of the cervical spine segment and intervertebral disk prosthesis

    Science.gov (United States)

    Kolmakova, T. V.; Rikun, Y. A.

    2017-10-01

    The article describes the model of intervertebral disc prosthesis and the results of study of mechanical behavior of the cervical spine segment. The results show that degenerative changes in the intervertebral disc lead to a change in the location of the regions of maximum Mises stresses in cervical spine segment. The presented geometric model of the intervertebral disc prosthesis is based on the experimental sample of a ceramic endoprosthesis developed at the Institute of Strength Physics and Materials Science SB RAS.

  5. Characterization of miRNA Expression in Human Degenerative Lumbar Disks

    DEFF Research Database (Denmark)

    Ohrt-Nissen, Søren; Døssing, Kristina B V; Rossing, Maria

    2013-01-01

    microRNAs (miRNAs) are short ∼22 nucleotide RNA sequences that regulate messengerRNA translation. miRNAs have shown to play a role in synthesis of inflammatory mediators. Since inflammation play a role in intervertebral disk (IVD) degeneration, the objective was to isolate miRNA from human lumbar...

  6. Doença do disco intervertebral em trabalhadores da perfuração de petróleo Intervertebral disk disease among oil drilling workers

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Pereira Fernandes

    2000-09-01

    Full Text Available Estudo transversal em 1.026 trabalhadores em distrito de perfuração de petróleo do Nordeste brasileiro mostrou prevalência global de doença do disco intervertebral lombar de 5%, variando de 1,8% (atividades sem manuseio de carga, 4,5% (manuseio ocasional até 7,2% (manuseio habitual. Tal prevalência foi de 11,4% em operadores de sonda de perfuração de petróleo com mais de 40 anos de idade e de 10,5% naqueles com mais de 15 anos de empresa. A razão de prevalência (R.P. à associação entre trabalho em operação de sonda e doença do disco foi 2,3 (I.C. 95%: 1,3, 4,0. Para minimizar o efeito sobrevivência do trabalhador sadio foram usadas informações retrospectivas acerca da exposição. A informação referente à ocupação atual em lugar do histórico ocupacional resultaria em RP subestimada de 1,1 (I.C. 95%: 0,6, 1,9. A regressão logística ratificou os achados da análise tabular. Não houve confundimento nem interação. O incremento da indústria de petróleo no país e as alterações na gestão e contratação da força de trabalho implicam mudanças no gerenciamento de risco e controle de saúde, além de pronta intervenção ergonômica para controle da doença.A cross-sectional study among 1,026 oil drilling workers in Northeast Brazil found a prevalence rate of 5% for intervertebral disk disease, varying from 1.8% (activities without heavy lifting and 4.5% (occasional lifting to 7.2% (routine lifting. Disease prevalence was 10.5% among drilling workers with more than 15 years in the industry and 11.3% among those over 40 years of age. Prevalence ratio (PR for the association between working in oil drilling operations and intervertebral disk disease was 2.3 (95% CI: 1.3-4.0. Retrospective information about exposure was collected to minimize the healthy worker survival effect. Using information on current occupation instead of occupational life history would cause an underestimated PR of 1.1 (95% CI: 0.6-1.9. Logistic

  7. MR abnormalities of the intervertebral disks and adjacent bone marrow as predictors of segmental instability of the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Braem, J.; Zanetti, M.; Hodler, J. [Orthopedic University Clinic Balgrist, Zurich (Switzerland). Dept. of Diagnostic Radiology; Min, K. [Orthopedic University Clinic Balgrist, Zurich (Switzerland). Dept. of Orthopedic Surgery

    1998-01-01

    Purpose: To assess whether MR abnormalities of the intervertebral disks and adjacent bone marrow can predict segmental instability of the lumbar spine as diagnosed on functional radiographs. Material and Methods: A consecutive review was made of 60 patients examined with MR imaging and with lateral flexion and extension views of the lumbar spine. Sagittal T1- and T2-weighted images were evaluated blindly with regard to abnormalities of the intervertebral disk and the adjacent bone marrow. Segmental instability was diagnosed when a.p. translation of 3 mm or more was present on the functional radiographs. Moreover, the presence of osteophytes was evaluated on lateral standard radiographs. Results: Of a total of 300 segments, 32 (10.7%) were unstable. Anular tears were the most relevant MR finding. Their sensitivity, specificity, and positive and negative predictive values for segmental instability were 18.8%, 97.0%, 42.9% and 90.9%. The corresponding values for traction osteophytes were 12.5%, 98.1%, 44.4% and 90.4%. Abnormalities of bone marrow were not significantly related to segmental instability (p=0.35). Conclusion: Functional radiographs should be considered in patients with anular tears or traction osteophytes. No correlation was found between segmental instability and abnormalities of bone marrow adjacent to the endplates. (orig.).

  8. Besonderheiten eines Bandscheibenvorfalles bei Spondylolisthese [ = Characteristics of an intervertebral disk herniation in spondylolisthesis

    OpenAIRE

    Grifka, Joachim; Möller, J.

    1991-01-01

    Treatment of intervertebral disc herniation associated with spondylolisthesis is not different from common procedures concerning indication for surgery and surgical technique as far as sciatica is not related to retrolisthetic soft tissue or the posterior edge of the vertebral body. In a case of a disc herniation L5/S1 and an olisthesis grade I with radicular pain L5 a microdiscectomy of the prolapse and parts of the retrolisthetic soft tissue was performed. An immediate reintervention was ne...

  9. Evaluation of the association between spondylosis deformans and clinical signs of intervertebral disk disease in dogs: 172 cases (1999-2000).

    Science.gov (United States)

    Levine, Gwendolyn J; Levine, Jonathan M; Walker, Michael A; Pool, Roy R; Fosgate, Geoffrey T

    2006-01-01

    To evaluate the association between spondylosis deformans and clinical signs of intervertebral disk disease (IVDD) in dogs. Retrospective case series. 210 dogs. Records of 172 dogs with clinical signs of IVDD and 38 dogs with other neurologic disorders were reviewed. Signalment, sites of spondylosis, severity of associated osteophytosis, type of disk herniation, and duration of signs were recorded. Dogs with IVDD had significantly fewer sites of involvement and lower grades of spondylosis deformans, compared with those in the non-IVDD group. When groups were adjusted for age and weight via multivariate linear regression, there were no differences in severity of osteophytosis or number of affected sites. Dogs with type II disk disease had higher numbers of affected sites and more severe changes, compared with dogs with type I disk herniation. There was no difference between groups in the rate at which IVDD was diagnosed at sites of spondylosis, compared with the rate at which IVDD was diagnosed in unaffected disk spaces. Areas of spondylosis were closer to sites of IVDD that elicited clinical signs than to randomly chosen intervertebral spaces, and distances between sites of spondylosis and sites of IVDD had a bimodal appearance. An association may exist between radiographically apparent spondylosis and type II disk disease; type I disk disease was not associated with spondylosis. Spondylosis in radiographs of dogs with suspected type I disk disease is not clinically important. Spatial associations among sites of spondylosis and sites of IVDD may be coincidental or associated with vertebral column biomechanics.

  10. An Experimental Study on the Effects of Smoking in the Perinatal Period and During Lactation on the Intervertebral Disks of Newborns.

    Science.gov (United States)

    Altun, Idiris; Yuksel, Kasım Z

    2017-03-01

    To evaluate the histopathologic effects of smoking before, during, and after pregnancy on the intervertebral disk structure of newborns in an experimental rat model. Seven adult female Wistar albino rats were randomly allocated into 7 groups. Nicotine (2 mg/kg/d) was intraperitoneally introduced to these rats in 6 groups before, during, and after pregnancy, whereas the rat in the control group received isotonic saline intraperitoneally. Fourteen newborns delivered by each rat were euthanized at the end of 9 weeks after being breastfed for 3 weeks after birth. The vertebral columns of the euthanized rats were removed en bloc, and histopathologic evaluation was performed on the intervertebral disk specimens. Histopathologic alterations were noted and compared between groups. Ratio of proteoglycan amount exhibited a significant difference between groups (P smoking before and during pregnancy and smoking before/during pregnancy and lactation resulted in deposition of a severe amount of proteoglycans in intervertebral disk tissue. Similarly, there was a statistically significant difference between groups with respect to the amount of fibrosis (P smoking before pregnancy and during lactation. A moderate degree of fibrosis was detected in groups with smoking during pregnancy, before and during pregnancy, during pregnancy and lactation, and before/during pregnancy and lactation. Results of this study imply that maternal smoking before and during pregnancy and in the lactation period may have deleterious effects on the intervertebral disk of the newborn. The duration of smoking and fertility period can influence the type and severity of these effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Anular delamination strength of human lumbar intervertebral disc.

    Science.gov (United States)

    Gregory, Diane E; Bae, Won C; Sah, Robert L; Masuda, Koichi

    2012-09-01

    Progression of intervertebral disc (IVD) herniation does not occur exclusively in a linear manner through the anulus fibrosus (AF), but can migrate circumferentially due to localized AF delamination. Consequently, resistance to delamination is an important factor in determining risk of herniation progression. The inter-lamellar matrix located between the AF layers is responsible for resisting this delamination; however, its mechanical properties are largely unknown. This study aimed to determine the mechanical properties of the inter-lamellar matrix in human AF samples via a peel test. Seventeen human IVDs (degeneration grades of 2-3) were obtained from six lumbar spines. From these 17 discs, 53 tissue samples were obtained from the superficial and deep regions of the anterior and posterior AF. Samples were dissected into a 'T' configuration to facilitate a T-peel test (or 180-degree peel test) by initiating delamination between the two middle AF layers. Peel strength was found to be 33 % higher in tissues obtained from the superficial AF region as compared with the deep region (p = 0.047). This finding may indicate a higher resistance to delamination in the superficial AF, and as a result, delamination and herniation progression may occur more readily in the deeper layers of the AF.

  12. [Basic principles of successful implantation of the SB Charité model LINK intervertebral disk endoprosthesis].

    Science.gov (United States)

    Büttner-Janz, K; Hahn, S; Schikora, K; Link, H D

    2002-05-01

    The scope of the LINK SB Charité Artificial Disc is to replace degeneratively changed, symptomatic intervertebral discs and to restitute the fundamental functions of the lumbar mobile segment. Biomechanical static- and dynamic test results as well as postoperative controls of a patient-group with uniform indications are presented. The options of an intervertebral disc replacement with the SB Charité Artificial Disc are discussed. For the evaluation of segmental stability, comparative static examinations of the range of motion of cadaveric lumbar segments prior to and after the implantation of the artificial disc were carried out. The stress-dependent mechanical response to directional static load on implanted SB Charité Discs in neutral position, extension and flexion was examined under different testing-conditions in order to gain results on changes of surfaces, durability and sustain of functionality. Restitutable changes to the UHMWPE sliding core, prognosed definite deformations of the sliding core after 5 and 10 years, and the functionality of the UHMWPE sliding cores after stress were examined using dynamic compression tests. Our clinical results refer to 20 patients, who received a mono- (n = 14) or bisegmental (n = 6) implantation of a SB Charité Artificial Disc following a postnucleotomy-syndrome. Comparison of the ranges of motion in cadaveric segments with and without a SB Charité Artificial Disc reflected a significantly higher mobility in cases with an implanted prosthesis only in axial rotation. Other movements showed similar ranges of motion in native segments and in segments with prosthesis. The UHMWPE sliding cores showed tolerable changes during maximal static compression in neutral position and extension. The 7.5 mm sliding cores showed changes beyond normal deformations on compression in maximal flexion. None the less it may be concluded that in vivo these sliding cores also retain their mechanical integrity. Most of the 7.5 mm and 9.5 mm

  13. High signal intensity on T1-weighted MR image related to vacuum cleft in the intervertebral disk; clinical and phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Tae Gyun; Kim, Yong Sun; Chang, Yongmin; Lee, Sang Kwon; Kim, Young Hwan; Ryeom, Hyun Kyu; Lee, Jong Min; Lee, Chang Hyon; Kim, Tae Hun [Kyungpook National Univ. College of Medicine , Taegu (Korea, Republic of); Suh, Kyung Jin [Suh and Joo MRI Center, Taegu (Korea, Republic of)

    2000-12-01

    To determine the possible mechanism by which an area of high signal intensity appears on T1-weighted MR images adjacent to a vacuum cleft in intervertebral disks. We analyzed a total of 14 disks in nine patients in whom a vacuum cleft with T1-signal hyperintensity was observed. Lesions were present from T11-12 to L5-S1 using a 1.5-T whole-body imager, sagittal spine-echo T1-weighted and gradient-echo images (flip angle, 20 .deg. and 60 .deg.) were obtained. In order to identify the vacuum cleft, using plain radiographs in all patients and CT scans in two were also obtained. A 3% agar-gel block containing empty slits to form a magnetic susceptibility difference, a phantom was designed. The air spaces were 1.6mm in thickness, 25mm in width, and 20 to 25mm in depth with 1.6-mm spacing. In all patients, vacuum clefts were confirmed by plain radiographs and CT scans. At the level containing air, T1-weighted images (both spin-echo and gradient-echo) showed a signal void resulting from the intervertebral disk vacuum cleft. A hyperintense band adjacent to the vacuum cleft was, however, observed. A gradient-echo image with a 60 .deg. flip angle showed a brighter signal intensity than one with a 20 .deg. angle. Our phantom study gave the same results. The magnetic susceptibility artifact may be responsible for the T1-signal hyperintensity observed adjacent to the vacuum cleft in intervertebral disks. In addition, in order to generate signal hyperintensity, the desiccating disk material must contain a certain amount of water molecules.

  14. [The characteristics of epidural analgesia during the removal of lumbar intervertebral disk hernias].

    Science.gov (United States)

    Arestov, O G; Solenkova, A V; Lubnin, A Iu; Shevelev, I N; Konovalov, N A

    2000-01-01

    Epidural analgesia (EA) was used in 29 patients undergoing surgical removal of lumbar discal hernia. Marcain EA with controlled medicinal sleep and non-assisted breathing allowed to perform the whole operation in 27 patients. EA may be ineffective in combination of sequestrated disk hernia with scarry adhesive process. The technique of the operation demands a single use of the anesthetic drug which is potent enough to make blockade throughout the operation up to the end.

  15. Reliability of macroscopic grading of intervertebral disk degeneration in dogs by use of the Thompson system and comparison with low-field magnetic resonance imaging findings.

    Science.gov (United States)

    Bergknut, Niklas; Grinwis, Guy; Pickee, Emile; Auriemma, Edoardo; Lagerstedt, Anne-Sofie; Hagman, Ragnvi; Hazewinkel, Herman A W; Meij, Björn P

    2011-07-01

    To evaluate the reliability of the Thompson system for use in grading the gross pathological changes of intervertebral disk (IVD) degeneration in dogs and to investigate the agreement between gross pathological findings and low-field (0.2-T) magnetic resonance imaging (MRI) findings. Vertebral columns from cadavers of 19 dogs of various ages, breeds, and origins. 182 intervertebral segments were collected from 19 canine cadavers. Sagittal T2-weighted MRI of the T11 through S1 portion of the vertebral column was performed within 24 hours after the dogs were euthanized. The vertebral columns were subsequently divided in the midsagittal plane, and high-resolution photographs were obtained of each intervertebral segment (end plate-disk-end plate). The MRI images and photographs were graded separately in a blinded manner by 4 observers who used both Pfirrmann and Thompson grading criteria. The interobserver agreement for Thompson scores ranged from 0.76 to 0.88, and the intraobserver agreement ranged from 0.88 to 0.94 (Cohen weighted κ analysis). Agreement between scores for the Pfirrmann and Thompson grading criteria was κ = 0.70. Grading of IVD degeneration in dogs by use of the Thompson system resulted in high interobserver and intraobserver agreement, and scores for the Thompson system had substantial agreement with low-field MRI findings graded by use of the Pfirrmann system. This suggested that low-field MRI can be used to diagnose IVD degeneration in dogs.

  16. Herniated disk

    Science.gov (United States)

    ... pulposus Herniated disk repair Lumbar spinal surgery - series Herniated lumbar disk References Gardocki RJ, Park AL. Lower back pain and disorders of intervertebral discs. In: Canale ST, Beaty JH, eds. Campbell's Operative ...

  17. Preliminary evaluation of the effects of photobiomodulation therapy and physical rehabilitation on early postoperative recovery of dogs undergoing hemilaminectomy for treatment of thoracolumbar intervertebral disk disease.

    Science.gov (United States)

    Bennaim, Michael; Porato, Mathilde; Jarleton, Astrid; Hamon, Martin; Carroll, James D; Gommeren, Kris; Balligand, Marc

    2017-02-01

    OBJECTIVE To evaluate the effects of postoperative photobiomodulation therapy and physical rehabilitation on early recovery variables for dogs after hemilaminectomy for treatment of intervertebral disk disease. ANIMALS 32 nonambulatory client-owned dogs. PROCEDURES Dogs received standard postoperative care with photobiomodulation therapy (n = 11), physical rehabilitation with sham photobiomodulation treatment (11), or sham photobiomodulation treatment only (10) after surgery. Neurologic status at admission, diagnostic and surgical variables, duration of postoperative IV analgesic administration, and recovery grades (over 10 days after surgery) were assessed. Time to reach recovery grades B (able to support weight with some help), C (initial limb movements present), and D (ambulatory [≥ 3 steps unassisted]) was compared among groups. Factors associated with ability to ambulate on day 10 or at last follow-up were assessed. RESULTS Time to reach recovery grades B, C, and D and duration of postoperative IV opioid administration did not differ among groups. Neurologic score at admission and surgeon experience were negatively associated with the dogs' ability to ambulate on day 10. The number of disk herniations identified by diagnostic imaging before surgery was negatively associated with ambulatory status at last follow-up. No other significant associations and no adverse treatment-related events were identified. CONCLUSIONS AND CLINICAL RELEVANCE This study found no difference in recovery-related variables among dogs that received photobiomodulation therapy, physical rehabilitation with sham photobiomodulation treatment, or sham photobiomodulation treatment only. Larger studies are needed to better evaluate effects of these postoperative treatments on dogs treated surgically for intervertebral disk disease.

  18. Longevity of elastin in human intervertebral disc as probed by the racemization of aspartic acid

    DEFF Research Database (Denmark)

    Sivan, Sarit-Sara; Van El, Benno; Merkher, Yulia

    2012-01-01

    BACKGROUND: Aging and degeneration of human intervertebral disc (IVD) are associated with biochemical changes, including racemization and glycation. These changes can only be counteracted by protein turnover. Little is known about the longevity of IVD elastin in health or disease. Yet, such knowl...

  19. Pulsed Electromagnetic Field Stimulates Cellular Proliferation in Human Intervertebral Disc Cells

    OpenAIRE

    Lee, Hwan-Mo; Kwon, Un-Hye; Kim, Hyang; Kim, Ho-Joong; Kim, Boram; Park, Jin-Oh; Moon, Eun-Soo; Moon, Seong-Hwan

    2010-01-01

    Purpose The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. Materials and Methods Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650?, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [3H]-...

  20. Knockdown of asporin affects transforming growth factor-β1-induced matrix synthesis in human intervertebral annulus cells

    Directory of Open Access Journals (Sweden)

    Xu Jiang

    2016-10-01

    Conclusion: Our results have verified a functional feedback loop between TGF-β1 and asporin in human intervertebral annulus cells indicating that TGF-β1-induced annulus matrix biosynthesis can be significantly upregulated by knockdown of asporin. Therefore, asporin could be a potential new therapeutic target and inhibition of asporin could be adopted to enhance the anabolic effect of TGF-β1 in human intervertebral annulus cells in degenerative IVD diseases.

  1. A 1-D model of the nonlinear dynamics of the human lumbar intervertebral disc

    Science.gov (United States)

    Marini, Giacomo; Huber, Gerd; Püschel, Klaus; Ferguson, Stephen J.

    2017-01-01

    Lumped parameter models of the spine have been developed to investigate its response to whole body vibration. However, these models assume the behaviour of the intervertebral disc to be linear-elastic. Recently, the authors have reported on the nonlinear dynamic behaviour of the human lumbar intervertebral disc. This response was shown to be dependent on the applied preload and amplitude of the stimuli. However, the mechanical properties of a standard linear elastic model are not dependent on the current deformation state of the system. The aim of this study was therefore to develop a model that is able to describe the axial, nonlinear quasi-static response and to predict the nonlinear dynamic characteristics of the disc. The ability to adapt the model to an individual disc's response was a specific focus of the study, with model validation performed against prior experimental data. The influence of the numerical parameters used in the simulations was investigated. The developed model exhibited an axial quasi-static and dynamic response, which agreed well with the corresponding experiments. However, the model needs further improvement to capture additional peculiar characteristics of the system dynamics, such as the change of mean point of oscillation exhibited by the specimens when oscillating in the region of nonlinear resonance. Reference time steps were identified for specific integration scheme. The study has demonstrated that taking into account the nonlinear-elastic behaviour typical of the intervertebral disc results in a predicted system oscillation much closer to the physiological response than that provided by linear-elastic models. For dynamic analysis, the use of standard linear-elastic models should be avoided, or restricted to study cases where the amplitude of the stimuli is relatively small.

  2. Nerve Growth Factor Is Regulated by Toll-Like Receptor 2 in Human Intervertebral Discs.

    Science.gov (United States)

    Krock, Emerson; Currie, J Brooke; Weber, Michael H; Ouellet, Jean A; Stone, Laura S; Rosenzweig, Derek H; Haglund, Lisbet

    2016-02-12

    Nerve growth factor (NGF) contributes to the development of chronic pain associated with degenerative connective tissue pathologies, such as intervertebral disc degeneration and osteoarthritis. However, surprisingly little is known about the regulation of NGF in these conditions. Toll-like receptors (TLR) are pattern recognition receptors classically associated with innate immunity but more recently were found to be activated by endogenous alarmins such as fragmented extracellular matrix proteins found in degenerating discs or cartilage. In this study we investigated if TLR activation regulates NGF and which signaling mechanisms control this response in intervertebral discs. TLR2 agonists, TLR4 agonists, or IL-1β (control) treatment increased NGF, brain-derived neurotrophic factor (BDNF), and IL-1β gene expression in human disc cells isolated from healthy, pain-free organ donors. However, only TLR2 activation or IL-1β treatment increased NGF protein secretion. TLR2 activation increased p38, ERK1/2, and p65 activity and increased p65 translocation to the cell nucleus. JNK activity was not affected by TLR2 activation. Inhibition of NF-κB, and to a lesser extent p38, but not ERK1/2 activity, blocked TLR2-driven NGF up-regulation at both the transcript and protein levels. These results provide a novel mechanism of NGF regulation in the intervertebral disc and potentially other pathogenic connective tissues. TLR2 and NF-κB signaling are known to increase cytokines and proteases, which accelerate matrix degradation. Therefore, TLR2 or NF-κB inhibition may both attenuate chronic pain and slow the degenerative progress in vivo. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Factors associated with recovery from paraplegia in dogs with loss of pain perception in the pelvic limbs following intervertebral disk herniation.

    Science.gov (United States)

    Jeffery, Nick D; Barker, Andrew K; Hu, Hilary Z; Alcott, Cody J; Kraus, Karl H; Scanlin, Elizabeth M; Granger, Nicolas; Levine, Jonathan M

    2016-02-15

    To investigate associations between recovery of locomotion and putative prognostic factors in dogs with loss of deep pain perception in the pelvic limbs caused by intervertebral disk herniation (IVDH). Prospective cohort study. 78 client-owned dogs evaluated for IVDH that underwent spinal decompression surgery. Dogs with complete loss of deep pain perception in the pelvic limbs and tail underwent routine examinations, advanced imaging, and spinal decompression surgery in accordance with standards of practice and owner consent. For each dog, information was prospectively collected on duration of clinical signs prior to onset of paraplegia; delay between onset of paraplegia and initial referral evaluation; date of recovery of locomotion, death, or euthanasia (3-month follow-up period); and whether dogs had received corticosteroid drugs before surgery. Severity of spinal cord compression at the lesion epicenter was measured via CT or MRI. 45 of 78 (58%) of dogs recovered the ability to ambulate independently within 3 months after spinal decompression surgery. No evidence of prognostic value was identified for any of the investigated factors; importantly, a greater delay between onset of paraplegia and referral evaluation was not associated with a poorer prognosis. In this group of dogs with IVDH, immediacy of surgical treatment had no apparent association with outcome. The prognosis for recovery may instead be strongly influenced by the precise nature of the initiating injury.

  4. Collagen turnover in normal and degenerate human intervertebral discs as determined by the racemization of aspartic acid

    NARCIS (Netherlands)

    Sivan, S.-S.; Wachtel, E.; Tsitron, E.; Sakkee, N.; Ham, F. van der; Groot, J.de; Roberts, S.; Maroudas, A.

    2008-01-01

    Knowledge of rates of protein turnover is important for a quantitative understanding of tissue synthesis and catabolism. In this work, we have used the racemization of aspartic acid as a marker for the turnover of collagen obtained from healthy and pathological human intervertebral disc matrices. We

  5. Recuperação funcional de cães com doença do disco intervertebral toracolombar submetidos ao tratamento cirúrgico Functional recovery of dogs with thoracolumbar intervertebral disk disease submitted the surgical treatment

    Directory of Open Access Journals (Sweden)

    Rafael Festugatto

    2008-11-01

    Full Text Available O objetivo deste estudo foi avaliar a recuperação funcional de 33 cães com doença do disco intervertebral (DDIV toracolombar submetidos ao tratamento cirúrgico, atendidos no Hospital Veterinário Universitário da Universidade Federal de Santa Maria (HVU-UFSM, no período entre 2004 e 2006. Os dados dos animais incluíram raça, idade, sexo, estado neurológico antes da cirurgia, interpretação da radiografia simples e contrastada, duração das deficiências neurológicas até o procedimento cirúrgico, tempo de recuperação pós-cirúrgico, função urinária e fecal e recidiva dos sinais clínicos. Quanto à duração dos sinais neurológicos antes da cirurgia, 27 (81,8% permaneceram por um período inferior a 15 dias, 20 cães tiveram melhora dos sinais clínicos decorridos 30 dias do procedimento cirúrgico e seis, com mais de 30 dias, sendo que um desses demorou 60 dias para caminhar. Apenas um (3,8% dos 26 cães que tiveram recuperação funcional satisfatória apresentou incontinência urinária e apenas um (3% teve recidiva da DDIV. Pode-se concluir que o tratamento cirúrgico promove recuperação funcional satisfatória na maioria dos cães com DDIV toracolombar. O prognóstico para recuperação funcional após o tratamento cirúrgico é tanto melhor quanto menor for o grau de disfunção neurológica e o percentual de recidiva é baixo em animais submetidos a este tipo de terapia.This report aimed at evaluating the functional recovery of 33 dogs with thoracolumbar intervertebral disk disease (IVDD admitted at the Veterinary Hospital of Santa Maria Federal University (HVU-UFSM, from 2004 to 2006. The animals underwent surgical treatment. Data obtained from the dogs included: breed, age, sex, neurological status before the surgery, interpretation of the simple x-ray and myelography, duration of clinical signs, days to walking after surgery, urinary and fecal function and disease recurrence. Neurological signs before the surgery

  6. Doença do disco intervertebral cervical em cães: 28 casos (2003-2008 Cervical intervertebral disk disease in dogs: 28 cases (2003-2008

    Directory of Open Access Journals (Sweden)

    Giancarlo Santini

    2010-08-01

    Full Text Available O objetivo deste estudo foi identificar cães com doença do disco intervertebral (DDIV cervical atendidos no Hospital Veterinário Universitário (HVU da Universidade Federal de Santa Maria (UFSM entre janeiro de 2003 e outubro de 2008 e obter informações a respeito de raça, sexo, idade, sinais neurológicos, resposta ao tratamento cirúrgico, complicações, tempo de recuperação funcional após a cirurgia e ocorrência de recidiva. Hiperestesia cervical foi observada em todos os cães (n=28. Quanto ao grau de disfunção neurológica foram verificados: grau I (8/28[28,5%], grau II (3/28 [10,7%], grau III (5/28[17,8%] e grau V (12/2 [42,8%]. A duração dos sinais neurológicos antes da cirurgia em sete cães (25% permaneceu por até 15 dias, em 14 cães (50% entre 15 e 30 dias e nos outros sete cães (25% por mais de 30 dias. A recuperação satisfatória e sem recidiva foi observada em todos os cães submetidos ao tratamento cirúrgico e que sobreviveram (n=21. Pode-se concluir que a DDIV cervical em nossa rotina acomete principalmente cães adultos, machos, de raças condrodistróficas e não condrodistróficas, incluindo as de grande porte; a hiperestesia cervical é a principal manifestação clínica; a técnica de fenda ventral promove recuperação funcional satisfatória e sem recidiva; as principais complicações trans-operatórias são a hemorragia do plexo venoso, a bradicardia e a hipotensão; e a duração dos sinais clínicos não interfere no tempo de recuperação pós-operatória dos cães.The aim of this study was to evaluate the medical records of dogs with cervical intervertebral disk disease (IDD, submitted to surgical treatment at the Hospital Veterinário Universitário of Universidade Federal de Santa Maria (HVU-UFSM, between January 2003 and October 2008. The animal data included breed, sex, age, neurological signs and their durations, response to surgical treatment, complications, time for functional recovery

  7. A large animal model that recapitulates the spectrum of human intervertebral disc degeneration.

    Science.gov (United States)

    Gullbrand, S E; Malhotra, N R; Schaer, T P; Zawacki, Z; Martin, J T; Bendigo, J R; Milby, A H; Dodge, G R; Vresilovic, E J; Elliott, D M; Mauck, R L; Smith, L J

    2017-01-01

    The objective of this study was to establish a large animal model that recapitulates the spectrum of intervertebral disc degeneration that occurs in humans and which is suitable for pre-clinical evaluation of a wide range of experimental therapeutics. Degeneration was induced in the lumbar intervertebral discs of large frame goats by either intradiscal injection of chondroitinase ABC (ChABC) over a range of dosages (0.1U, 1U or 5U) or subtotal nucleotomy. Radiographs were used to assess disc height changes over 12 weeks. Degenerative changes to the discs and endplates were assessed via magnetic resonance imaging (MRI), semi-quantitative histological grading, microcomputed tomography (μCT), and measurement of disc biomechanical properties. Degenerative changes were observed for all interventions that ranged from mild (0.1U ChABC) to moderate (1U ChABC and nucleotomy) to severe (5U ChABC). All groups showed progressive reductions in disc height over 12 weeks. Histological scores were significantly increased in the 1U and 5U ChABC groups. Reductions in T2 and T1ρ, and increased Pfirrmann grade were observed on MRI. Resorption and remodeling of the cortical boney endplate adjacent to ChABC-injected discs also occurred. Spine segment range of motion (ROM) was greater and compressive modulus was lower in 1U ChABC and nucleotomy discs compared to intact. A large animal model of disc degeneration was established that recapitulates the spectrum of structural, compositional and biomechanical features of human disc degeneration. This model may serve as a robust platform for evaluating the efficacy of therapeutics targeted towards varying degrees of disc degeneration. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  8. Stress - Strain Response of the Human Spine Intervertebral Disc As an Anisotropic Body. Mathematical Modeling and Computation

    Directory of Open Access Journals (Sweden)

    Minárová Mária

    2016-01-01

    Full Text Available The paper deals with the biomechanical investigation on the human lumbar intervertebral disc under the static load. The disc is regarded as a two - phased ambient consisting of a fibrous outer part called annulus fibrosis and a liquid inner part nucleus pulposus. Due to the fibrous structure, the annulus fibrosis can be treated by using a special case of anisotropy - transversal isotropy.

  9. Biomechanics of the human intervertebral disc: A review of testing techniques and results.

    Science.gov (United States)

    Newell, N; Little, J P; Christou, A; Adams, M A; Adam, C J; Masouros, S D

    2017-05-01

    Many experimental testing techniques have been adopted in order to provide an understanding of the biomechanics of the human intervertebral disc (IVD). The aim of this review article is to amalgamate results from these studies to provide readers with an overview of the studies conducted and their contribution to our current understanding of the biomechanics and function of the IVD. The overview is presented in a way that should prove useful to experimentalists and computational modellers. Mechanical properties of whole IVDs can be assessed conveniently by testing 'motion segments' comprising two vertebrae and the intervening IVD and ligaments. Neural arches should be removed if load-sharing between them and the disc is of no interest, and specimens containing more than two vertebrae are required to study 'adjacent level' effects. Mechanisms of injury (including endplate fracture and disc herniation) have been studied by applying complex loading at physiologically-relevant loading rates, whereas mechanical evaluations of surgical prostheses require slower application of standardised loading protocols. Results can be strongly influenced by the testing environment, preconditioning, loading rate, specimen age and degeneration, and spinal level. Component tissues of the disc (anulus fibrosus, nucleus pulposus, and cartilage endplates) have been studied to determine their material properties, but only the anulus has been thoroughly evaluated. Animal discs can be used as a model of human discs where uniform non-degenerate specimens are required, although differences in scale, age, and anatomy can lead to problems in interpretation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Isolation and identification of stem cells from degenerated human intervertebral discs and their migration characteristics.

    Science.gov (United States)

    Liu, Shuhao; Liang, Haifeng; Lee, Soo-Min; Li, Zheng; Zhang, Jian; Fei, Qinming

    2017-02-06

    Mesenchymal stem cells (MSCs) have been isolated and identified separately from the three components of intervertebral disc, i.e. annulus fibrosus (AF), nucleus pulposus (NP), and cartilage endplate (CEP). However, few studies have been carried out to compare the properties of these three kinds of stem cells, especially their migration ability which is essential for their potential clinical application. In this study, MSCs were isolated from AF, NP, and CEP, respectively, of human degenerated discs and identified by surface markers and multilineage differentiation assay at passage 3. These three types of stem cells were named as AF-MSCs, NP-MSCs, and CEP-MSCs. Then, their biological characteristics were compared in terms of proliferation, passage, colony formation, migration, and invasion capacity. Results showed that all the three types of cells were identified as MSCs and had similar characteristics in proliferation, passage, and colony formation capacity. CEP-MSCs showed the highest migration and invasion potency, while NP-MSCs showed the lowest migration ability and almost no invasion potency, suggesting that CEP-MSCs had the most powerful properties of migration and invasion when compared with AF-MSCs and NP-MSCs. It was also found that the expression of CXCR4 was higher in CEP-MSCs than in the other two, suggesting that SDF-1/CXCR4 axis may play significant roles in the migration of these cells.

  11. Ultrastructure of inclusion bodies in annulus cells in the degenerating human intervertebral disc.

    Science.gov (United States)

    Gruber, H E; Hanley, E N

    2009-06-01

    The rough endoplasmic reticulum (rER) of the cell has an architectural editing function that checks whether protein structure and three-dimensional assembly have occurred properly prior to export of newly synthesized material out of the cell. If these have been faulty, the material is retained within the rER as an inclusion body. Inclusion bodies have been identified previously in chondrocytes and osteoblasts in chondrodysplasias and osteogenesis imperfecta. Inclusion bodies in intervertebral disc cells, however, have only recently been recognized. Our objectives were to use transmission electron microscopy to analyze more fully inclusion bodies in the annulus pulposus and to study the extracellular matrix (ECM) surrounding cells containing inclusion bodies. ECM frequently encapsulated cells with inclusion bodies, and commonly contained prominent banded aggregates of Type VI collagen. Inclusion body material had several morphologies, including relatively smooth, homogeneous material, or a rougher, less homogeneous feature. Such findings expand our knowledge of the fine structure of the human disc cell and ECM during disc degeneration, and indicate the potential utility of ultrastructural identification of discs with intracellular inclusion bodies as a screening method for molecular studies directed toward identification of defective gene products in degenerating discs.

  12. Pulsed electromagnetic field stimulates cellular proliferation in human intervertebral disc cells.

    Science.gov (United States)

    Lee, Hwan-Mo; Kwon, Un-Hye; Kim, Hyang; Kim, Ho-Joong; Kim, Boram; Park, Jin-Oh; Moon, Eun-Soo; Moon, Seong-Hwan

    2010-11-01

    The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650 Ω, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [(3)H]-thymidine, and [(35)S]-sulfate incorporation. To detect phenotypical expression, reverse transcription-polymerase chain reactions (RT-PCR) were performed for aggrecan, collagen type I, and type II mRNA expression. To assess action mechanism of EMF, IVD cells were exposed to EMF with N(G)-Monomethyl-L-arginine (NMMA) and acetylsalicylic acid (ASA). There was no cytotoxicity in IVD cells with the EMF group in MTT assay. Cellular proliferation was observed in the EMF group (p EMF group and the control. Cultures with EMF showed no significant change in the expression of aggrecan, type I, and type II collagen mRNA compared to the control group. Cultures with NMMA (blocker of nitric oxide) or ASA (blocker of prostaglandin E2) exposed to EMF demonstrated decreased DNA synthesis compared to control cultures without NMMA or ASA (p EMF stimulated DNA synthesis in human IVD cells while no significant effect on proteoglycan synthesis and chondrogenic phenotype expressions. DNA synthesis was partially mediated by nitric oxide and prostaglandin E2. EMF can be utilized to stimulate proliferation of IVD cells, which may provide efficient cell amplification in cell therapy to degenerative disc disease.

  13. Age-Correlated Phenotypic Alterations in Cells Isolated from Human Degenerated Intervertebral Discs With Contained Hernias.

    Science.gov (United States)

    Molinos, Maria; Cunha, Carla; Almeida, Catarina R; Gonçalves, Raquel M; Pereira, Paulo; Silva, Pedro Santos; Vaz, Rui; Barbosa, Mário A

    2017-07-03

    Human intervertebral disc (hIVD) cells were isolated from 41 surgically excised samples and assessed for their phenotypic alterations with age. Towards the design of novel anti-ageing strategies to overcome degenerative disc disease (DDD), we investigated age-correlated phenotypic alterations that occur on primary hIVD cells. Although regenerative medicine holds great hope, much is still to be unveiled on IVD cell biology and its intrinsic signalling pathways, which can lead the way to successful therapies for IDD. A greater focus on age-related phenotypic changes at the cell level would contribute to establish more effective anti-ageing/degeneration targets. The study was subdivided in four main steps: i) optimization of primary cells isolation technique; ii) high-throughput cell morphology analysis, by imaging flow-cytometry (FC) and subsequent validation by histological analysis; iii) analysis of progenitor cell surface markers expression, by conventional FC; and iv) statistical analysis and correlation of cells morphology and phenotype with donor age. Three subsets of cells were identified based on their diameter: small (SC), large (LC) and super large cells (SLC). The frequency of SCs decreased nearly 50% with age, whereas that of LCs increased nearly 30%. Interestingly, the increased cells size was due to an enlargement of the pericellular matrix (PCM). Moreover, the expression pattern for CD90 and CD73 was a reflexion of age, where older individuals show reduced frequencies of positive cells for those markers. Nevertheless, the elevated percentages of primary positive cells for the mesenchymal stem cells (MSC) marker CD146 found, even in some older donors, bring refreshed hope for the hypothetical activation of the self-renewal potential of the IVD. These findings highlight the remarkable morphological alterations that occur on hIVD cells with ageing and degeneration, while reinforcing previous reports on the gradual disappearance of an endogenous progenitor

  14. Influences of Nutrition Supply and Pathways on the Degenerative Patterns in Human Intervertebral Disc.

    Science.gov (United States)

    Zhu, Qiaoqiao; Gao, Xin; Levene, Howard B; Brown, Mark D; Gu, Weiyong

    2016-04-01

    Investigation of the effects of the impairment of different nutritional pathways on the intervertebral disc degeneration patterns in terms of spatial distributions of cell density, glycosaminoglycan content, and water content. The aim of this study was to test the hypothesis that impairment of different nutritional pathways would result in different degenerative patterns in human discs. Impairment of nutritional pathways has been found to affect cell viability in the disc. However, details on how impairment of different nutritional pathways affects the disc degeneration patterns are unknown. A 3D finite element model was used for this study. This finite element method was based on the cell-activity coupled mechano-electrochemical theory for cartilaginous tissues. Impairment of the nutritional pathways was simulated by lowering the nutrition level at the disc boundaries. Effects of the impartment of cartilaginous endplate-nucleus pulposus (CEP-NP) pathway only (Case 1), annulus fibrosus (AF) pathway only (Case 2), and both pathways (Case 3) on disc degeneration patterns were studied. The predicted critical levels of nutrition for Case 1, Case 2, and Case 3 were around 30%, 20%, and 50% of the reference values, respectively. Below this critical level, the disc degeneration would occur. Disc degeneration appeared mainly in the NP for Case 1, in the outer AF for Case 2, and in both the NP and inner to middle AF for Case 3. For Cases 1 and 3, the loss of water content was primarily located in the mid-axial plane, which is consistent with the horizontal gray band seen in some T2-weighted magnetic resonance imaging (MRI). For the disc geometry used in this study, it was predicted that there existed a high-intensity zone (for Case 3), as seen in some T2-weighted MRI images. Impairment of different nutrition pathways results in different degenerative patterns. N/A.

  15. Expression of the two pore domain potassium channel TREK-1 in human intervertebral disc cells.

    Science.gov (United States)

    Sharma, Pankaj; Hughes, Stephen; El Haj, Alicia; Maffulli, Nicola

    2012-07-01

    Potassium channels play a major role in intracellular homeostasis and regulation of cell volume. Intervertebral disc cells respond to mechanical loading in a complex manner. Mechanical loading may play a role in disc degeneration. Lumbar intervertebral disc samples from 5 patients (average age: 47 years, range: 25-64 years) were used for this study, investigating cells from the nucleus pulposus and the annulus fibrosus duplicate samples to determine RNA expression and protein expression. Analysis of mRNA expression by RT-PCR demonstrated that TREK 1 was expressed by nucleus pulposus (n=5) and annulus fibrosus (n=5) cells. Currently, TREK-1 is the only potassium channel known to be activated by intracellular acidosis, and responds to mechanical and chemical stimuli. Whilst the precise role of potassium channels in cellular homeostasis remains to be determined, TREK-1 may be important to protect disc cells against ischaemic damage, and subsequent disc degeneration, and may also play a role in effecting mechanotransduction. Further research is required to fully elucidate the role of the TREK-1 ion channel in intervertebral disc cells.

  16. The relationship between pregnancy-associated plasma protein-A (PAPP-A) and human intervertebral disc degeneration.

    Science.gov (United States)

    Gruber, Helen E; Buchanan, Laura; Ingram, Jane A; Zinchenko, Natalia; Norton, H James; Hanley, Edward N

    2010-11-01

    Pregnancy-associated plasma protein-A (PAPP-A), a metalloproteinase expressed by a number of cell types, has the important role of cleaving insulin-like growth factor (IGF)-binding protein-2, -4 and -5 in the extracellular matrix and thus freeing up IGF and making it available to cells. The objective of the present study was to utilize immunocytochemical analysis to determine the proportion of PAPP-A-positive cells in a large group of disc specimens which covered the spectrum of changes from relatively healthy Thompson grade II discs to extremely degenerate grade V discs. Work was approved by our institutional human subjects review board. Seventy-two intervertebral disc specimens were assessed for immunocytochemical localization of PAPP-A and the proportion of positive cells determined in the outer annulus, inner annulus and nucleus pulposus. The percentage of PAPP-A positive cells in both the outer and inner annulus correlated significantly with increasing stages of disc degeneration in a fashion which was not dependent upon subject age. There was no significant difference in the percentage of PAPP-A positive cells in the inner annulus of herniated vs non-herniated sites, or in the outer annulus of herniated vs non-herniated sites. Data reported here point to the importance of additional work to elucidate the role of PAPP-A in intervertebral disc aging and degeneration.

  17. The presence and absence of lymphatic vessels in the adult human intervertebral disc: relation to disc pathology

    Energy Technology Data Exchange (ETDEWEB)

    Kliskey, Karolina; Williams, Kelly; Yu, J.; Urban, Jill; Athanasou, Nick [University of Oxford, Nuffield Department of Orthopaedic, Rheumatology and Musculoskeletal Science, Oxford (United Kingdom); Jackson, David [Weatherall Institute of Molecular Medicine, Human Immunology Unit, Oxford (United Kingdom)

    2009-12-15

    Although the normal adult human intervertebral disc is considered to be avascular, vascularised cellular fibrous tissue can be found in pathological conditions involving the disc such as disc herniation. Whether lymphatics vessels form a component of this reparative tissue is not known as the presence or absence of lymphatics in herniated and normal disc tissue is not known. We examined spinal tissues and discectomy specimens for the presence of lymphatics. The examination used immunohistochemistry to identify the specific lymphatic endothelial cell markers, podoplanin and LYVE1. Lymphatic vessels were not found in the nucleus pulposus or annulus fibrosus of intact, non-herniated lumbar and thoracic discs but were present in the surrounding ligaments. Ingrowth of fibrous tissue was seen in 73% of herniated disc specimens of which 36% contained LYVE1+/podoplanin + lymphatic vessels. Lymphatic vessels were not seen in the sacrum and coccyx or biopsies of four sacrococcygeal chordomas, but they were noted in surrounding extra-osseous fat and fibrous tissue at the edge of the infiltrating tumour. Our findings indicate that lymphatic vessels are not present in the normal adult intervertebral disc but that, when there is extrusion of disc material into surrounding soft tissue, there is ingrowth of reparative fibrous tissue containing lymphatic vessels. Our findings also indicate that chordoma, a tumour of notochordal origin, spreads to regional lymph nodes via lymphatics in para-spinal soft tissues. (orig.)

  18. 1988 Volvo award in basic science. Proteoglycan synthesis in the human intervertebral disc. Variation with age, region and pathology.

    Science.gov (United States)

    Bayliss, M T; Johnstone, B; O'Brien, J P

    1988-09-01

    Slices of human annulus fibrosus were cultured under conditions that controlled their hydration and prevented loss of proteoglycans from the extracellular matrix. A quantitative analysis of proteoglycan synthesis was carried out. Both the absolute rate of synthesis and the topographical variation in chondrocyte activity changed with age; the most active cells in the adult were found in the mid-annulus region, whereas in the fetal disc the cells in the inner annulus were the most active. The conditions under which the tissue was stored, and changes in hydration during culture, had considerable effects on synthesis. Pathological discs had a wide range of biological activity that reflected the heterogeneous properties of these specimens. It is suggested that this culture method provides a means of investigating the way in which the synthesis of the macromolecular components of the intervertebral disc are coordinated and subsequently incorporated into the extracellular matrix.

  19. Human-induced pluripotent stem cells generated from intervertebral disc cells improve neurologic functions in spinal cord injury.

    Science.gov (United States)

    Oh, Jinsoo; Lee, Kang-In; Kim, Hyeong-Taek; You, Youngsang; Yoon, Do Heum; Song, Ki Yeong; Cheong, Eunji; Ha, Yoon; Hwang, Dong-Youn

    2015-06-24

    Induced pluripotent stem cells (iPSCs) have emerged as a promising cell source for immune-compatible cell therapy. Although a variety of somatic cells have been tried for iPSC generation, it is still of great interest to test new cell types, especially those which are hardly obtainable in a normal situation. In this study, we generated iPSCs by using the cells originated from intervertebral disc which were removed during a spinal operation after spinal cord injury. We investigated the pluripotency of disc cell-derived iPSCs (diPSCs) and neural differentiation capability as well as therapeutic effect in spinal cord injury. The diPSCs displayed similar characteristics to human embryonic stem cells and were efficiently differentiated into neural precursor cells (NPCs) with the capability of differentiation into mature neurons in vitro. When the diPSC-derived NPCs were transplanted into mice 9 days after spinal cord injury, we detected a significant amelioration of hindlimb dysfunction during follow-up recovery periods. Histological analysis at 5 weeks after transplantation identified undifferentiated human NPCs (Nestin(+)) as well as early (Tuj1(+)) and mature (MAP2(+)) neurons derived from the transplanted NPCs. Furthermore, NPC transplantation demonstrated a preventive effect on spinal cord degeneration resulting from the secondary injury. This study revealed that intervertebral discs removed during surgery for spinal stabilization after spinal cord injury, previously considered a "waste" tissue, may provide a unique opportunity to study iPSCs derived from difficult-to-access somatic cells and a useful therapeutic resource for autologous cell replacement therapy in spinal cord injury.

  20. Cisto intraespinal em comunicação com o disco intervertebral na coluna lombar: relato de um caso e revisão da literatura Quiste intraespinhal en comunicación con el disco intervertebral em la columna lumbar: reporte de caso y revisión de la literatura Intraspinal cyst communicating with the intervertebral disk in the lumbar spine: case report and literature review

    Directory of Open Access Journals (Sweden)

    Mauricio Marteleto Filho

    2012-12-01

    ículo se describen las características de esta entidad clínica, incluyendo el aspecto clínico, radiológico e histológico, para discutir la posible patogénesis y tratamiento.Herniated lumbar disc is an important as well as the most common cause of low back pain and sciatica. Many cases can be readily diagnosed by simple semiological examination. Magnetic resonance imaging (MRI provides a definitive diagnosis even in an outpatient basis. Several types of intraspinal cysts with different pathogenesis have been reported in the past, such as perineural cysts, synovial cysts, arachnoid cysts, and ganglion cysts, diseases that are difficult to differentiate from lumbar disc herniation. Recently, the authors have observed one case of intraspinal cyst communicating with the corresponding intervertebral disk, presenting clinical symptoms, signs, and even some radiographic findings undistinguishable from those of herniated disks. The diagnosis established by MRI and confirmed at surgery. This paper describes the features of this distinct clinical condition, including clinical findings, images, and histological aspects, to discuss possible pathogenesis and management.

  1. 1997 Volvo Award winner in basic science studies. Immunohistologic markers for age-related changes of human lumbar intervertebral discs.

    Science.gov (United States)

    Nerlich, A G; Schleicher, E D; Boos, N

    1997-12-15

    The authors performed a correlative macroscopic, histologic, and immunohistochemical investigation on human lumbar intervertebral discs using complete motion segment slices, including all age groups and stages of degeneration. To identify markers for age-related changes of human lumbar intervertebral discs. In particular, to investigate changes in the distribution pattern of collagen Types I, II, III, IV, V, VI, IX, and X. In addition, to study posttranslational protein modification by the immunolocalization of N-(carboxylmethyl)lysine (CML), which is regarded as a biomarker for oxidative stress. Data on a correlation of age-related changes in disc morphology and disc matrix composition is sparse. So far, no comprehensive analysis considered a correlation of macroscopic, histologic, and biochemical age-related alterations using complete sections of intervertebral discs (i.e., including nucleus pulposus, anulus fibrosus, endplates, and vertebral bodies). In addition, there is need for specific markers for these disc changes to allow for a better correlation with disc function. After photodocumentation of the macroscopic appearance, 229 sagittal lumbar motion segments obtained from 47 individuals (fetal to 86 years) during routine autopsy were processed for histologic and immunohistochemical analysis. All slices were investigated for histologic alterations of disc degeneration. A randomly selected subset of these specimens (n = 45) was used for a correlative analysis of interstitial collagens and molecular modifications of matrix proteins. The presence of CML-modification of extracellular matrix proteins, mainly collagen, was observed first in the nucleus pulposus of a 13-year-old individual and increased significantly with age. In elderly people, both the nucleus pulposus and the anulus fibrosus showed extensive CML deposition. This CML deposition was accentuated in areas of macroscopic and histologic disc degeneration. After the occurrence of CML in the nucleus

  2. Best paper NASS 2013: link-N can stimulate proteoglycan synthesis in the degenerated human intervertebral discs.

    Science.gov (United States)

    Gawri, Rahul; Antoniou, John; Ouellet, Jean; Awwad, Waleed; Steffen, Thomas; Roughley, Peter; Haglund, Lisbet; Mwale, Fackson

    2013-09-11

    Intervertebral disc (IVD) degeneration is the most common cause of back pain. Presently there is no medical treatment, leaving surgery as the only offered option. Here we evaluate the potential of Link-N to promote extracellular matrix regeneration in human IVDs. Human disc cells cultured in alginate and intact human discs were exposed to a combination of Link-N and ³⁵SO₄ in the presence or absence of interleukin (IL)-1, and the effect on proteoglycan synthesis was evaluated. In addition, message levels of aggrecan, matrix metalloproteinase (MMP)-3, MMP-13, a Disintegrin And Metalloproteinase with Thrombospondin Motifs (ADAMTS)-4 and ADAMTS-5 were evaluated in alginate cultures. Human disc cells responded in a dose dependent manner with maximal proteoglycan synthesis at 1 µg/mL Link-N. Link-N treatment also induced proteoglycan synthesis in intact human discs, and a prolonged effect was found up to one week after Link-N treatment. Message levels of proteinases were decreased by Link-N in the presence of IL-1. Thus, Link-N can promote proteoglycan synthesis and deplete proteinase expression in adult human discs. Link-N could therefore be a promising candidate for biologically-induced disc repair, and could provide an alternative to surgical intervention for early stage disc degeneration.

  3. Interleukin-2 is upregulated in patients with a prolapsed lumbar intervertebral disc and modulates cell proliferation, apoptosis and extracellular matrix metabolism of human nucleus pulposus cells

    Science.gov (United States)

    WANG, ZHIRONG; WANG, GENLIN; ZHU, XUESONG; GENG, DECHUN; YANG, HUILIN

    2015-01-01

    Previous studies have demonstrated that the expression levels of cytokines are increased in degenerated intervertebral disc tissues, and several cytokines are associated with the pathogenesis of intervertebral disc degeneration. However, the role of interleukin (IL)-2 in the cellular functions of intervertebral disc tissues remains unreported. The present study aimed to determine the expression levels of IL-2 in the nucleus pulposus (NP) tissues of patients with a prolapsed lumbar intervertebral disc; and to observe the changes in cell proliferation, apoptosis, extracellular matrix (ECM) metabolism and p38 mitogen-activated protein kinase (MAPK) signaling in human NP cells (HNPCs) following treatment with IL-2. The present study demonstrated that IL-2 expression levels were upregulated in the NP tissues of patients with a prolapsed lumbar intervertebral disc; and a subsequent MTT assay demonstrated that IL-2 inhibits the proliferation of HNPCs in a dose-dependent manner. Furthermore, as demonstrated by the increased protein expression levels of Fas cell surface death receptor and the induction of caspase-8 and caspase-3 activity, the death receptor pathway was activated by IL-2 in the HNPCs in order to promote cell apoptosis. In addition, IL-2 promoted ECM degradation in the HNPCs, as demonstrated by an increase in the expression levels of type I collagen, a disintegrin and metalloproteinase with thrombospondin motifs and matrix metalloproteinases, and decreased aggrecan and type II collagen expression levels. Furthermore, phosphorylated-p38 was significantly increased in the HNPCs following IL-2 treatment. In conclusion, the present study demonstrated that IL-2 inhibits cell proliferation, and induces cell apoptosis and ECM degradation, accompanied by the activation of p38 MAPK signaling in HNPCs. Therefore, IL-2 may be a potential therapeutic agent for the treatment of degenerative disc disease. PMID:26668654

  4. MR imaging of spondylolytic spondylolisthesis: changes of intervertebral foramen and nerve root compression

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Hyung [Ajou Univ. College of Medicine, Seoul (Korea, Republic of); Chung, Tae Sub; Kim, Young Soo [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-08-01

    To evaluate the factors affecting intervertebral foramen stenosis and nerve root compression in spondylolytic spondylolisthesis. We investigated 120 intervertebral foramina of 60 patients with spondylolytic spondylolisthesis who had undergone lumbar MRI. A retrospective review of their MR images revealed the degree of intervertebral foramen stenosis and causes of nerve root compression. The relationship between disk height diminution following spondylolysis and degree of intervertebral foramen stenosis was also evaluated. Forty eight of 60 patients showed a similar degree of intervertebral foramen stenosis, and in 12 patients the degree of stenosis was different. In 110 intervertebral foramina, stenosis of both the superior and inferior compartments of intervertebral foramina was demonstrated. In 37 of 120 cases (30.8%), stenosis was mild ; in 44 of 120 (36.7%) it was modcrate, and in 29 of 120 (24.2%) it was severe. Stenosis of the inferior compartment was demonstrated in ten of 120 intervertebral foramina (8.3%). Nerve root compression was caused by posterior bulging of the intervertebral disk (65/120), descent of the pedicle (51/120), an isthmic bony segment above the site of spondylolytic (44/120), a bony spur formed at a spondylolytic site (11/120), and fibrocartilaginous callus at a spondylolytic site (5/48). In all cases there was degenerative change of the intervertebral disk at the affected level. There was no relationship between degree of disk height diminution and degree of intervertebral foramen stenosis (p > 0.05). The degree of intervertebral foramen stenosis and causes of nerve root compression in spondylolytic spondylolisthesis are variable, and MRI demonstrates them precisely. There was no positive relationship between degree of nerve root compression at an intervertebral foramen and degree of spondylolysis and degeneration of an intervertebral foramen. The degree of nerve root compression is believed to be another criterion for describing

  5. Comparison of outcomes between minimally invasive transforaminal lumbar interbody fusion and traditional posterior lumbar intervertebral fusion in obese patients with lumbar disk prolapse

    OpenAIRE

    Wang YP; An JL; Sun YP; Ding WY; Shen Y; Zhang W.

    2017-01-01

    Ya-Peng Wang,* Ji-Long An,* Ya-Peng Sun,* Wen-Yuan Ding, Yong Shen, Wei Zhang Department of Spinal Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China *These authors contributed equally to this work Objective: The aim of this study was to compare the curative effect between minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and the posterior lumbar interbody fusion (PLIF) in obese patients with lumbar disk prolap...

  6. Intervertebral disc degeneration in dogs

    NARCIS (Netherlands)

    Bergknut, N.

    2011-01-01

    Back pain is common in both dogs and humans, and is often associated with intervertebral disc (IVD) degeneration. The IVDs are essential structures of the spine and degeneration can ultimately result in diseases such as IVD herniation or spinal instability. In order to design new treatments halting

  7. Intervertebral disc degeneration in dogs

    NARCIS (Netherlands)

    Bergknut, Niklas

    Back pain is common in both dogs and humans, and is often associated with intervertebral disc (IVD) degeneration. The IVDs are essential structures of the spine and degeneration can ultimately result in diseases such as IVD herniation or spinal instability. In order to design new treatments halting

  8. Glycosaminoglycan chemical exchange saturation transfer in human lumbar intervertebral discs: Effect of saturation pulse and relationship with low back pain.

    Science.gov (United States)

    Wada, Tatsuhiro; Togao, Osamu; Tokunaga, Chiaki; Funatsu, Ryohei; Yamashita, Yasuo; Kobayashi, Kouji; Nakamura, Yasuhiko; Honda, Hiroshi

    2017-03-01

    To evaluate the dependence of saturation pulse power and duration on glycosaminoglycan chemical exchange saturation transfer (gagCEST) imaging and assess the degeneration of human lumbar intervertebral discs (IVDs) using this method. All images were acquired on a 3T magnetic resonance imaging (MRI) scanner. The CEST effects were measured in the glycosaminoglycan (GAG) phantoms with different concentrations. In the human study, CEST effects were measured in the nucleus pulposus of IVD. We compared the CEST effects among the different saturation pulse powers (0.4, 0.8, and 1.6 μT) or durations (0.5, 1.0, and 2.0 sec) at each Pfirrmann grade (I-V). The relationship between the CEST effects and low back pain was also evaluated. The phantom study showed high correlations between the CEST effects and GAG concentration (R 2  = 0.863, P low back pain were significantly lower than those in the groups without pain (P pain (P = 0.0216). The contrast of gagCEST imaging in the lumbar IVDs varied with saturation pulse power and duration. GagCEST imaging may serve as a tool for evaluating IVD degeneration in the lumbar spine. 2 J. Magn. Reson. Imaging 2017;45:863-871. © 2016 International Society for Magnetic Resonance in Medicine.

  9. Comparison of Preoperative Quantitative Magnetic Resonance Imaging and Clinical Assessment of Deep Pain Perception as Prognostic Tools for Early Recovery of Motor Function in Paraplegic Dogs with Intervertebral Disk Herniations.

    Science.gov (United States)

    Wang-Leandro, A; Siedenburg, J S; Hobert, M K; Dziallas, P; Rohn, K; Stein, V M; Tipold, A

    2017-05-01

    Prognostic tools to predict early postoperative motor function recovery (MFR) after thoracolumbar intervertebral disk herniation (IVDH) in paraplegic dogs represent an opportunity to timely implement novel therapies that could shorten recovery times and diminish permanent neurological dysfunctions. Fractional anisotropy (FA) values obtained using diffusion tensor imaging have a higher prognostic value than a lesion extension ratio in T2-weighted images (T2W-LER) and clinical assessment of deep pain perception (DPP) for MFR. Thirty-five paraplegic dogs with diagnosis of acute or subacute thoracolumbar IVDH. Prospective, descriptive observational study. At admission, absence or presence of DPP, T2W-LER, and FA values was evaluated. MFR was assessed within 4 weeks after decompressive surgery. Values of T2W-LER and FA of dogs with and without MFR were compared using t-tests. All 3 methods were evaluated for their sensitivity and specificity as a prognostic factor. No differences were found between groups regarding T2W-LER. FA values differed statistically when measured caudally of lesion epicenter being higher in dogs without MFR compared to dogs with MFR (P = .023). Logistic regression analysis revealed significance in FA values measured caudally of the lesion epicenter (P = .033, area under the curve = 0.72). Using a cutoff value of FA = 0.660, the technique had a sensitivity of 80% and a specificity of 55%. Evaluation of DPP had a sensitivity of 73.3% and specificity of 75% (P = .007). Evaluation of DPP showed a similar sensitivity and a better specificity predicting early MFR than quantitative magnetic resonance imaging. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  10. The Effect of the Acupuncture Therapy in Combination with Soyeom Pharmacopuncture Therapy on the Improvement of the Symptoms of the Patients with Herniated Intervertebral Disk of L-spine in His Initial Stage of Hospitalization

    Directory of Open Access Journals (Sweden)

    Song Hyong-gun

    2009-12-01

    Full Text Available Objectives: Herniated Intervertebral Disk(HIVD of L-spine is one of the most common diseases that cause back pain and radiating pain. The aim of this study is to find out if the acupuncture therapy combined with Soyeom Pharmacopuncture therapy can improve the symptoms of the patients suffering from the disease more effectively than the acupuncture only therapy. Methods: We separated 30 patients into two groups. Group A was treated with the acupuncture only therapy, and Group B was treated with Soyeom Pharmacopuncture therapy in addition to the acupuncture therapy. We have observed patients for 7 days. We checked the Visual Analog Scale(VAS for 4 times and did Straight Leg Raising Test(SLRT twice. Results: 1. For 7 days from the admission day, the VAS score has been decreased significantly in both Group A and Group B. 2. For 7 days from the admission day, the VAS score of Group B has been appeared signifi cantly lower than that of Group A, so that we can know that patients in Group B has more rapidly improved than patients in Group A 3. From the admission day to the 3rd hospital day, the improvement index of VAS scroe of Group B has appeared significantly higher than that of Group A, but after 5th hospital day, there was no significance between the improvement index of VAS score of Group A and that of Group B. 4. For 7 days from the admission day, the SLRT(degree has been improved significantly in both Group A and B, but there was no significance between the SLRT(degree of Group A and that of Group B. Conclusion: We can use Soyeom Pharmacopuncture therapy with acupuncture therapy to make the patients suffering from back pain and radiating pain improve more rapidly.

  11. Effect of the Degenerative State of the Intervertebral Disc on the Impact Characteristics of Human Spine Segments

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    Sara eWilson

    2013-12-01

    Full Text Available Models of the dynamic response of the lumbar spine have been used to examine vertebral fractures during falls and whole body vibration transmission in the occupational setting. Although understanding the viscoelastic stiffness or damping characteristics of the lumbar spine are necessary for modeling the dynamics of the spine, little is known about the effect of intervertebral disc degeneration on these characteristics at high loading rates. We hypothesize that disc degeneration significantly affects the viscoelastic response of spinal segments to high loading rate. We additionally hypothesize the lumbar spine stiffness and damping characteristics are a function of the degree of preload. A custom, pendulum impact tester was used to impact 19 L1-L3 human spine segments with an end mass of 20.9kg under increasing preloads with the resulting force response measured. A Kelvin–Voigt model, fitted to the frequency and decay response of the post-impact oscillations was used to compute stiffness and damping constants. The spine segments exhibited a second-order, underdamped response with stiffness and damping values of 17.9 - 754.5kN/m and 133.6 - 905.3Ns/m respectively. Regression models demonstrated that stiffness, but not damping, significantly correlated with preload (p

  12. Regenerative and immunogenic characteristics of cultured nucleus pulposus cells from human cervical intervertebral discs.

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    Stefan Stich

    Full Text Available Cell-based regenerative approaches have been suggested as primary or adjuvant procedures for the treatment of degenerated intervertebral disc (IVD diseases. Our aim was to evaluate the regenerative and immunogenic properties of mildly and severely degenerated cervical nucleus pulposus (NP cells with regard to cell isolation, proliferation and differentiation, as well as to cell surface markers and co-cultures with autologous or allogeneic peripheral blood mononuclear cells (PBMC including changes in their immunogenic properties after 3-dimensional (3D-culture. Tissue from the NP compartment of 10 patients with mild or severe grades of IVD degeneration was collected. Cells were isolated, expanded with and without basic fibroblast growth factor and cultured in 3D fibrin/poly (lactic-co-glycolic acid transplants for 21 days. Real-time reverse-transcription polymerase chain reaction (RT-PCR showed the expression of characteristic NP markers ACAN, COL1A1 and COL2A1 in 2D- and 3D-culture with degeneration- and culture-dependent differences. In a 5,6-carboxyfluorescein diacetate N-succinimidyl ester-based proliferation assay, NP cells in monolayer, regardless of their grade of degeneration, did not provoke a significant proliferation response in T cells, natural killer (NK cells or B cells, not only with donor PBMC, but also with allogeneic PBMC. In conjunction with low inflammatory cytokine expression, analyzed by Cytometric Bead Array and fluorescence-activated cell sorting (FACS, a low immunogenicity can be assumed, facilitating possible therapeutic approaches. In 3D-culture, however, we found elevated immune cell proliferation levels, and there was a general trend to higher responses for NP cells from severely degenerated IVD tissue. This emphasizes the importance of considering the specific immunological alterations when including biomaterials in a therapeutic concept. The overall expression of Fas receptor, found on cultured NP cells, could have

  13. A Constitutive Model for the Annulus of Human Intervertebral Disc: Implications for Developing a Degeneration Model and Its Influence on Lumbar Spine Functioning

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    J. Cegoñino

    2014-01-01

    Full Text Available The study of the mechanical properties of the annulus fibrosus of the intervertebral discs is significant to the study on the diseases of lumbar intervertebral discs in terms of both theoretical modelling and clinical application value. The annulus fibrosus tissue of the human intervertebral disc (IVD has a very distinctive structure and behaviour. It consists of a solid porous matrix, saturated with water, which mainly contains proteoglycan and collagen fibres network. In this work a mathematical model for a fibred reinforced material including the osmotic pressure contribution was developed. This behaviour was implemented in a finite element (FE model and numerical characterization and validation, based on experimental results, were carried out for the normal annulus tissue. The characterization of the model for a degenerated annulus was performed, and this was capable of reproducing the increase of stiffness and the reduction of its nonlinear material response and of its hydrophilic nature. Finally, this model was used to reproduce the degeneration of the L4L5 disc in a complete finite element lumbar spine model proving that a single level degeneration modifies the motion patterns and the loading of the segments above and below the degenerated disc.

  14. Regional variations in certain cellular characteristics in human lumbar intervertebral discs, including the presence of alpha-smooth muscle actin.

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    Hastreiter, D; Ozuna, R M; Spector, M

    2001-07-01

    An evaluation of the regional variation of certain cellular features in the human intervertebral disc (IVD) could lead to a better understanding of site-specific properties relative to degradation, response to injury, and healing processes. The objective of this study was to determine how cell density, cell morphology, cell grouping, and expression of a specific actin isoform varied with location and degeneration in the human disc. A total of 41 human L4-L5 and L5-S1 discs removed postmortem from 21 individuals were analyzed. The discs were graded for degeneration based on the Thompson scale and processed for evaluation. Microtomed sections from paraffin-embedded specimens were stained with hematoxylin and eosin or a monoclonal antibody to alpha-smooth muscle actin (alpha-SMA), an actin isoform often associated with contraction. A significant regional dependence was found for most of the measured parameters. A fourfold increase in cell density was found in proceeding from the nucleus pulposus (NP) to the outer annulus (OA) of the IVD. Approximately 30% of the cells in the NP were present in groups. Virtually all of the cells in the NP and 40% of those in the OA were round. Moreover, notable percentages (12-15%) of the cells in the NP and inner annulus (IA) contained alpha-SMA. Only pair density was found to be correlated with Thompson grade, with more degenerated specimens having higher values. A greater effect was also observed on the percentage of cells in groups. These findings provide the basis for future work to investigate the importance of cells in groups, the role of alpha-SMA in the disc, and the changes in these cellular characteristics in pathological disc conditions.

  15. Stability of housekeeping genes in human intervertebral disc, endplate and articular cartilage cells in multiple conditions for reliable transcriptional analysis.

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    Lopa, S; Ceriani, C; Cecchinato, R; Zagra, L; Moretti, M; Colombini, A

    2016-05-27

    Quantitative gene expression analysis is widely used to evaluate the expression of specific tissue markers. To obtain reliable data it is essential to select stable housekeeping genes whose expression is not influenced by the anatomical origin of cells or by the culture conditions. No studies have evaluated housekeeping gene stability in intervertebral disc (IVD) cells and only few studies using cartilaginous endplate (CEP) and articular cartilage (AC) cells are present in the literature. We analysed the stability of four candidate housekeeping genes (GAPDH, TBP, YWHAZ and RPL13A) in human cells isolated from nucleus pulposus (NP) and annulus fibrosus (AF), CEP and AC. Cell isolation, expansion, cryoconservation, and differentiation in 3D pellets were tested. GeNorm, NormFinder, BestKeeper tools and the comparative ΔCt method were used to evaluate housekeeping gene stability. In each cell population, TBP alone or combined with YWHAZ was identified as the best normaliser in both monolayer and 3D pellets. GAPDH was the best performer only for AC cells in monolayer. In most culture conditions considering groups of two or more cell types, TBP was the most stable and YWHAZ was the second choice. GAPDH was the best performer only in 3D pellets with factors for AC and AF combined with CEP cells. RPL13A was the most stable only for AF with CEP cells at isolation. Our findings will be useful to properly design the experimental set-up of studies involving IVD, CEP or AC cells in different culture conditions, in order to obtain accurate and high quality data from quantitative gene expression analysis.

  16. Stem cell therapy for intervertebral disc regeneration: review article

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    Mohsen Sheykhhasan

    2017-02-01

    Full Text Available Intervertebral disks (IVD acts as shock absorber between each of the vertebrae in the spinal column by keeping the vertebrae separated when the shock caused by the action. They also serve to protect the nerves that run down the middle of the spine and intervertebral disks. The disks are made of fibrocartilaginous material. The outside of the disk is made of a strong material called the annulus fibrosus. Inside this protective covering is a jelly-like substance known as mucoprotein gel. This interior is known as the nucleus pulposus. The nucleus pulposus consists of large vacuolated notochord cells, small chondrocyte-like cells, collagen fibrils, and aggrecan, a proteoglycan that aggregates by binding to hyaluronan. Attached to each aggrecan molecule are glycosaminoglycan (GAG chains of chondroitin sulfate and keratan sulfate. Intervertebral disks degeneration is frequently associated with low back and neck pain, which accounts as a disability. Despite the known outcomes of the Intervertebral disks degeneration cascade, the treatment of IVD degeneration is limited in that available conservative and surgical treatments do not reverse the pathology or restore the IVD tissue. Regenerative medicine for IVD degeneration, by injection of Intervertebral disks cells, chondrocytes or stem cells, has been extensively studied in the past decade in various animal models of induced IVD degeneration, and has progressed to clinical trials in the treatment of various spinal disease. Despite preliminary results showing positive effects of cell-injection strategies for IVD regeneration, detailed basic research on Intervertebral disks cells and their niche demonstrates that transplanted cells are unable to survive and adapt in the avascular niche of the IVD. For this therapeutic strategy to succeed, the indications for its use and the patients who would benefit need to be better defined. To surmount these obstacles, the solution will be identified only by focused

  17. Influence of facet joint angles and asymmetric disk collapse on degenerative olisthesis of the cervical spine.

    Science.gov (United States)

    Pellengahr, C; Pfahler, M; Kuhr, M; Hohmann, D

    2000-07-01

    This study examined the facet angles of the joint facets of the intervertebral joints, the anterior and posterior heights of the intervertebral disks, and cervical lordosis as possible parameters of olisthesis. Lateral radiographs of the cervical spine in 123 patients were examined, and parameters were correlated to anterolisthesis and retrolisthesis in each segment. Results indicate anterolisthesis is caused by a decrease of the facet angles of the caudal joint facets. This process is favored by loss of anterior height of the intervertebral disks and a flattened position of the cervical spine. Loss of posterior height of the intervertebral disks promotes retrolisthesis.

  18. Avaliação dos resultados clínicos após cirurgia descompressiva em cães com doença de disco intervertebral Evaluation of clinical results of decompressive surgery in dogs with degenerative disk disease

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    M.V.B. Arias

    2007-12-01

    Full Text Available Avaliaram-se os resultados clínicos após realização de cirurgia descompressiva em 45 cães com doença do disco intervertebral cervical ou toracolombar. Após a cirurgia, 35 cães (77,8% recuperaram-se totalmente, oito (17,8% parcialmente e dois (4,4% não apresentaram alteração do quadro inicial. Em oito cães com paraplegia e perda da sensibilidade dolorosa profunda houve completa melhora do quadro clínico, com recuperação total em 62,5% dos casos. Em quatro cães com tetraparesia, a cirurgia foi eficaz. A cirurgia descompressiva (slot cervical e hemilaminectomia toracolombar, com a retirada do material do disco do interior do canal vertebral, foi uma forma efetiva de gerar melhora do quadro funcional.Clinical results after decompressive surgery were evaluated in 45 dogs with cervical or thoracolumbar intervertebral disk disease. After surgery, 35 dogs recovered totally, eight (17.8% partially, and two (4.4% did not present any change in clinical findings. Eight dogs with paraplegy and loss of deep pain perception showed improvement, with total recovering in 62.5% of cases. Surgery was effective in four dogs with tetraparesy. Decompressive surgery (cervical slot or hemilaminectomy, with removal of disk material from inside the vertebral canal, was an effective form to produce functional improvement in dogs with this disease.

  19. Surface Characterization and Human Stem Cell Behaviors of Zirconia Implant Disks Biomimetic-Treated in Simulated Body Fluid.

    Science.gov (United States)

    Quan, Hongxuan; Park, Yoon-Kyung; Kim, Seong-Kyun; Heo, Seong-Joo; Koak, Jai-Young; Han, Jung-Suk; Lee, Joo-Hee

    2016-01-01

    This study investigated the effects of biomimetic deposition on a zirconia surface in simulated body fluid (SBF) and assessed the proliferation and differentiation of human bone marrow mesenchymal stem cells on the SBF-treated zirconia disks. Corrected SBF was prepared according to Kokubo's recipe. Eighty yttrium oxide-stabilized tetragonal zirconia polycrystalline disks were prepared and divided into two groups: (1) the test group with SBF-treated disks and (2) the control group with nontreated disks. Zirconia disks were soaked in SBF for 1, 4, 7, and 14 days at 36.5°C, and the hydroxyapatite (HA) precipitation was verified by analyzing the surface morphology. For more in-depth validation of HA formation, the surface roughness, composition, and crystallization of the 7-day treated disks were analyzed. Human bone marrow mesenchymal stem cells were used to further evaluate cell proliferation, alkaline phosphatase activity, and osteoblast gene expression on the 7-day treated zirconia disks. Disks showed different surface morphologies after soaking for different time periods. As the SBF soaking time increased, the amount of HA coverage increased gradually, uniformly covering the disks by day 7. There was no difference in surface roughness between the two groups (P > .05). Cell proliferation was higher on the SBF-treated disks (P .05). This study demonstrated that biomimetic deposition has an effect on the formation of HA on zirconia disks. The cell attachment, proliferation, and differentiation of SBF-treated zirconia disks was superior to that of nontreated disks, which indicates that SBF-treated zirconia implants have long-term clinical value.

  20. Native nucleus pulposus tissue matrix promotes notochordal differentiation of human induced pluripotent stem cells with potential for treating intervertebral disc degeneration.

    Science.gov (United States)

    Liu, Yongxing; Fu, Susan; Rahaman, Mohamed N; Mao, Jeremy J; Bal, B Sonny

    2015-03-01

    Native porcine nucleus pulposus (NP) tissue harbors a number of notochordal cells (NCs). Whether the native NP matrix supports the homeostasis of notochordal cells is poorly understood. We hypothesized the NP matrix alone may contain sufficient regulatory factors and can serve as stimuli to generate notochordal cells (NCs) from human pluripotent stem cells. NCs are a promising cell sources for cell-based therapy to treat some types of intervertebral disc (IVD) degeneration. One major limitation of this emerging technique is the lack of available NCs as a potential therapeutic cell source. Human pluripotent stem cells derived from reprogramming or somatic cell nuclear transfer technique may yield stable and unlimited source for therapeutic use. We devised a new method to use porcine NP matrix to direct notochordal differentiation of human induced pluripotent stem cells (hiPSCs). The results showed that hiPSCs successfully differentiated into NC-like cells under the influence of devitalized porcine NP matrix. The NC-like cells expressed typical notochordal marker genes including brachyury (T), cytokeratin-8 (CK-8) and cytokeratin-18 (CK-18), and they displayed the ability to generate NP-like tissue in vitro, which was rich in aggrecan and collagen type II. These findings demonstrated the proof of concept for using native NP matrix to direct notochordal differentiation of hiPSCs. It provides a foundation for further understanding the biology of NCs, and eventually towards regenerative therapies for disc degeneration. © 2014 Wiley Periodicals, Inc.

  1. The species-specific regenerative effects of notochordal cell-conditioned medium on chondrocyte-like cells derived from degenerated human intervertebral discs.

    NARCIS (Netherlands)

    Bach, FC; de Vries, S A H; Krouwels, A; Creemers, L B; Ito, K; Meij, B P; Tryfonidou, M A

    2015-01-01

    During intervertebral disc (IVD) maturation, the main cell type shifts from notochordal cells (NCs) to chondrocyte-like cells (CLCs). NCs secrete factors with regenerative potential, making them an interesting focus for regenerative treatments. During initial development, these strategies preferably

  2. The species-specific regenerative effects of notochordal cell-conditioned medium on chondrocyte-like cells derived from degenerated human intervertebral discs

    NARCIS (Netherlands)

    Bach, F C; de Vries, S A; Krouwels, A; Creemers, L B; Ito, K; Meij, B P; Tryfonidou, M A

    2015-01-01

    During intervertebral disc (IVD) maturation, the main cell type shifts from notochordal cells (NCs) to chondrocyte-like cells (CLCs). NCs secrete factors with regenerative potential, making them an interesting focus for regenerative treatments. During initial development, these strategies preferably

  3. Role of hypoxia and growth and differentiation factor-5 on differentiation of human mesenchymal stem cells towards intervertebral nucleus pulposus-like cells.

    Science.gov (United States)

    Stoyanov, J V; Gantenbein-Ritter, B; Bertolo, A; Aebli, N; Baur, M; Alini, M; Grad, S

    2011-06-20

    There is evidence that mesenchymal stem cells (MSCs) can differentiate towards an intervertebral disc (IVD)-like phenotype. We compared the standard chondrogenic protocol using transforming growth factor beta-1 (TGFß) to the effects of hypoxia, growth and differentiation factor-5 (GDF5), and coculture with bovine nucleus pulposus cells (bNPC). The efficacy of molecules recently discovered as possible nucleus pulposus (NP) markers to differentiate between chondrogenic and IVD-like differentiation was evaluated. MSCs were isolated from human bone marrow and encapsulated in alginate beads. Beads were cultured in DMEM (control) supplemented with TGFß or GDF5 or under indirect coculture with bNPC. All groups were incubated at low (2 %) or normal (20 %) oxygen tension for 28 days. Hypoxia increased aggrecan and collagen II gene expression in all groups. The hypoxic GDF5 and TGFß groups demonstrated most increased aggrecan and collagen II mRNA levels and glycosaminoglycan accumulation. Collagen I and X were most up-regulated in the TGFß groups. From the NP markers, cytokeratin-19 was expressed to highest extent in the hypoxic GDF5 groups; lowest expression was observed in the TGFß group. Levels of forkhead box F1 were down-regulated by TGFß and up-regulated by coculture with bNPC. Carbonic anhydrase 12 was also down-regulated in the TGFß group and showed highest expression in the GDF5 group cocultured with bNPC under hypoxia. Trends in gene expression regulation were confirmed on the protein level using immunohistochemistry. We conclude that hypoxia and GDF5 may be suitable for directing MSCs towards the IVD-like phenotype.

  4. Improving the Process of Adjusting the Parameters of Finite Element Models of Healthy Human Intervertebral Discs by the Multi-Response Surface Method.

    Science.gov (United States)

    Gómez, Fátima Somovilla; Lorza, Rubén Lostado; Bobadilla, Marina Corral; García, Rubén Escribano

    2017-09-21

    The kinematic behavior of models that are based on the finite element method (FEM) for modeling the human body depends greatly on an accurate estimate of the parameters that define such models. This task is complex, and any small difference between the actual biomaterial model and the simulation model based on FEM can be amplified enormously in the presence of nonlinearities. The current paper attempts to demonstrate how a combination of the FEM and the MRS methods with desirability functions can be used to obtain the material parameters that are most appropriate for use in defining the behavior of Finite Element (FE) models of the healthy human lumbar intervertebral disc (IVD). The FE model parameters were adjusted on the basis of experimental data from selected standard tests (compression, flexion, extension, shear, lateral bending, and torsion) and were developed as follows: First, three-dimensional parameterized FE models were generated on the basis of the mentioned standard tests. Then, 11 parameters were selected to define the proposed parameterized FE models. For each of the standard tests, regression models were generated using MRS to model the six stiffness and nine bulges of the healthy IVD models that were created by changing the parameters of the FE models. The optimal combination of the 11 parameters was based on three different adjustment criteria. The latter, in turn, were based on the combination of stiffness and bulges that were obtained from the standard test FE simulations. The first adjustment criteria considered stiffness and bulges to be equally important in the adjustment of FE model parameters. The second adjustment criteria considered stiffness as most important, whereas the third considered the bulges to be most important. The proposed adjustment methods were applied to a medium-sized human IVD that corresponded to the L3-L4 lumbar level with standard dimensions of width = 50 mm, depth = 35 mm, and height = 10 mm. Agreement between the

  5. Improving the Process of Adjusting the Parameters of Finite Element Models of Healthy Human Intervertebral Discs by the Multi-Response Surface Method

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    Fátima Somovilla Gómez

    2017-09-01

    Full Text Available The kinematic behavior of models that are based on the finite element method (FEM for modeling the human body depends greatly on an accurate estimate of the parameters that define such models. This task is complex, and any small difference between the actual biomaterial model and the simulation model based on FEM can be amplified enormously in the presence of nonlinearities. The current paper attempts to demonstrate how a combination of the FEM and the MRS methods with desirability functions can be used to obtain the material parameters that are most appropriate for use in defining the behavior of Finite Element (FE models of the healthy human lumbar intervertebral disc (IVD. The FE model parameters were adjusted on the basis of experimental data from selected standard tests (compression, flexion, extension, shear, lateral bending, and torsion and were developed as follows: First, three-dimensional parameterized FE models were generated on the basis of the mentioned standard tests. Then, 11 parameters were selected to define the proposed parameterized FE models. For each of the standard tests, regression models were generated using MRS to model the six stiffness and nine bulges of the healthy IVD models that were created by changing the parameters of the FE models. The optimal combination of the 11 parameters was based on three different adjustment criteria. The latter, in turn, were based on the combination of stiffness and bulges that were obtained from the standard test FE simulations. The first adjustment criteria considered stiffness and bulges to be equally important in the adjustment of FE model parameters. The second adjustment criteria considered stiffness as most important, whereas the third considered the bulges to be most important. The proposed adjustment methods were applied to a medium-sized human IVD that corresponded to the L3–L4 lumbar level with standard dimensions of width = 50 mm, depth = 35 mm, and height = 10 mm

  6. Mechanotransduction in intervertebral discs.

    Science.gov (United States)

    Tsai, Tsung-Ting; Cheng, Chao-Min; Chen, Chien-Fu; Lai, Po-Liang

    2014-12-01

    Mechanotransduction plays a critical role in intracellular functioning--it allows cells to translate external physical forces into internal biochemical activities, thereby affecting processes ranging from proliferation and apoptosis to gene expression and protein synthesis in a complex web of interactions and reactions. Accordingly, aberrant mechanotransduction can either lead to, or be a result of, a variety of diseases or degenerative states. In this review, we provide an overview of mechanotransduction in the context of intervertebral discs, with a focus on the latest methods of investigating mechanotransduction and the most recent findings regarding the means and effects of mechanotransduction in healthy and degenerative discs. We also provide some discussion of potential directions for future research and treatments. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  7. Human fetal osteoblast behavior on zirconia dental implants and zirconia disks with microstructured surfaces. An experimental in vitro study.

    Science.gov (United States)

    Delgado-Ruíz, Rafael Arcesio; Gomez Moreno, Gerardo; Aguilar-Salvatierra, Antonio; Markovic, Aleksa; Mate-Sánchez, Jose Eduardo; Calvo-Guirado, José Luis

    2016-11-01

    To measure the lateral surface area of microgrooved zirconia implants, to evaluate the cell geometry and cell density of human fetal osteoblasts seeded on zirconia microgrooved implants, to describe the surface roughness and chemistry, and to evaluate the activity of human fetal osteoblasts seeded on zirconia microgrooved disks. This experimental in vitro study used 62 zirconia implants and 130 zirconia disks. Two experimental groups were created for the implants: 31 non-microgrooved implants (Control) and 31 microgrooved implants (Test); two experimental groups were created for the disks: 65 non-microgrooved disks (Control) and 65 microgrooved disks (Test). The following evaluations of the implants were made: lateral surface area (LSA), cell morphology, and density of human fetal osteoblasts seeded on implant surfaces. On the disks, surface parameters (roughness and chemistry) and cell activity (alkaline phosphatase - ALP and alizarin red - ALZ) were evaluated at 7 and 15 days. LSA was lower for control implants (62.8 mm) compared with test implants (128.74 mm) (P implants presented cells rich in lamellipodia prolongations, attached to the inner walls or to the borders of the microgrooves and in the flat areas between the microgrooves. Cell density was higher in the test group compared with controls (P implants with microgrooves. (ii) The LSA of microgrooved zirconia implants is greater and provides more available surface compared with implants of the same dimensions without microgrooves. (iii) Microgrooves on zirconia implants modify the morphology and guide the size and alignment of human fetal osteoblasts. (iv) Zirconia surfaces with microgrooves of 30 μm width and 70 μm separation between grooves enhance ALP and ALZ expression by human fetal osteoblasts. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. MRI evaluation of spontaneous intervertebral disc degeneration in the alpaca cervical spine.

    Science.gov (United States)

    Stolworthy, Dean K; Bowden, Anton E; Roeder, Beverly L; Robinson, Todd F; Holland, Jacob G; Christensen, S Loyd; Beatty, Amanda M; Bridgewater, Laura C; Eggett, Dennis L; Wendel, John D; Stieger-Vanegas, Susanne M; Taylor, Meredith D

    2015-12-01

    Animal models have historically provided an appropriate benchmark for understanding human pathology, treatment, and healing, but few animals are known to naturally develop intervertebral disc degeneration. The study of degenerative disc disease and its treatment would greatly benefit from a more comprehensive, and comparable animal model. Alpacas have recently been presented as a potential large animal model of intervertebral disc degeneration due to similarities in spinal posture, disc size, biomechanical flexibility, and natural disc pathology. This research further investigated alpacas by determining the prevalence of intervertebral disc degeneration among an aging alpaca population. Twenty healthy female alpacas comprised two age subgroups (5 young: 2-6 years; and 15 older: 10+ years) and were rated according to the Pfirrmann-grade for degeneration of the cervical intervertebral discs. Incidence rates of degeneration showed strong correlations with age and spinal level: younger alpacas were nearly immune to developing disc degeneration, and in older animals, disc degeneration had an increased incidence rate and severity at lower cervical levels. Advanced disc degeneration was present in at least one of the cervical intervertebral discs of 47% of the older alpacas, and it was most common at the two lowest cervical intervertebral discs. The prevalence of intervertebral disc degeneration encourages further investigation and application of the lower cervical spine of alpacas and similar camelids as a large animal model of intervertebral disc degeneration. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  9. [Individualized treatment of lumbar intervertebral disc herniation].

    Science.gov (United States)

    Han, Jian; Tang, Yong-an; Yin, Zhan-hai

    2009-04-01

    To investigate the necessity, practicability for individualized treatment of lumbar intervertebral disc herniation and analyze its clinical effect. Five hundred and three cases of lumbar intervertebral disc herniation from March 2005 to March 2008 were individually treated by conservative treatment, minimal surgical procedures, open operation according to the protrusible size, rupture status of annular fibrosus, liberation or prolapse of disk tissue, accompanying conditions like spinal stenosis, spondylolisthesis or nerve involvement. Three hundred and ninety-three cases (male 189, female 204) were followed with an average age of 44.6 years old (range from 23 to 76). Among them, 210 cases were treated by conservative method, 145 cases by minimal surgical procedures and 38 cases by open operation. Therapeutic effect was evaluated by Macnab criteria. The mean follow-up duration was 16 months (range from 3 months to 3 years). Therapeutic effect was noted as 346 of excellence, 29 of effective, 18 of ineffective. Excellence rate was 88%(346/393) and effective rate was 95% (375/393). No severe complication was found. The recurrence rate of conservative treatment, minimal surgical procedures, open operation was respectively 18.1% (38/210), 9.6% (14/145), 5.3% (2/38). Conservative treatment is generally applied, its effect is reliable for patients of mild symptom. Minimal surgical procedures is applied more and more wide, the method will become prevalent. The indications for open operation became stricter and traditional surgical methods was challenged by less invasive methods. Individualized treatment basing on indication judgment was the most importance to improve therapeutic effect.

  10. Assembly of the cardiac intercalated disk during pre- and postnatal development of the human heart.

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    Arnold Vreeker

    Full Text Available In cardiac muscle, the intercalated disk (ID at the longitudinal cell-edges of cardiomyocytes provides as a macromolecular infrastructure that integrates mechanical and electrical coupling within the heart. Pathophysiological disturbance in composition of this complex is well known to trigger cardiac arrhythmias and pump failure. The mechanisms underlying assembly of this important cellular domain in human heart is currently unknown.We collected 18 specimens from individuals that died from non-cardiovascular causes. Age of the specimens ranged from a gestational age of 15 weeks through 11 years postnatal. Immunohistochemical labeling was performed against proteins comprising desmosomes, adherens junctions, the cardiac sodium channel and gap junctions to visualize spatiotemporal alterations in subcellular location of the proteins.Changes in spatiotemporal localization of the adherens junction proteins (N-cadherin and ZO-1 and desmosomal proteins (plakoglobin, desmoplakin and plakophilin-2 were identical in all subsequent ages studied. After an initial period of diffuse and lateral labelling, all proteins were fully localized in the ID at approximately 1 year after birth. Nav1.5 that composes the cardiac sodium channel and the gap junction protein Cx43 follow a similar pattern but their arrival in the ID is detected at (much later stages (two years for Nav1.5 and seven years for Cx43, respectively.Our data on developmental maturation of the ID in human heart indicate that generation of the mechanical junctions at the ID precedes that of the electrical junctions with a significant difference in time. In addition arrival of the electrical junctions (Nav1.5 and Cx43 is not uniform since sodium channels localize much earlier than gap junction channels.

  11. MR imaging findings of lumbar scheuermann's disease: correlation with disk pathologies

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    Kim, Jong Yeol; Lee, Sang Kwon; Kim, Byung Ki; Kim, Yong Woon; Kim, Tae Hyun; Kim, Yong Joo; Kang, Duk Sik [Kyungpook National University College of Medicine, Taegu (Korea, Republic of)

    1999-02-01

    To describe the MR imaging findings of lumber Scheuermann's disease and to determine the relationship between various MR imaging findings of this disease and disk pathologies. We retrospectively evaluated the MR imaging findings of 13 patients under the age of 20 with lumbar Scheuermann's disease. One hundred and four vertebral bodies and 91 intervertebral disks were included in the study. The imaging findings were analyzed with particular emphasis on the wedging of vertebral bodies, Schmorl's nodes, and the height of intervertebral disks. The relationship between these findings and disk degeneration or herniation was evaluated. Lumbar Scheuermann's disease was classified into two types according to Blumenthal's classification. Seven patients were type 1 and six were type 2. Disk degeneration and herniation were identified in 28.6%(26/91) and 20.9%(19/91), respectively, of intervertebral disks. In type 1, wedging of the vertebral bodies was noted in 48.2% of cases(27/56) and degeneration and herniation of adjacent disks were identified in 24.1%(7/29) and 13.8%(4/29), respectively. Central Schmorl's nodes were identified in 29.5%(33/112) of end-plates and degeneration and herniation of adjacent disks in 34.8%(8/23) and 17.4%(4/23), respectively. In type 2, anterior Schmorl's nodes were found in 11.5%(11/96) of end-plates and degeneration and herniation of adjacent disks in 100%(10/10) and 70%(7/10), respectively. Decreased height of intervertebral disks was noted adjacent to the anterior Schmorl's nodes ; all were related to disk degeneration and 70%(7/10) to disk herniation. There was statistically significant correlation between anterior Schmorl's node, decreased height of intervertebral disk and adjacent disk pathologies(p < 0.05), but wedged vertebra and central Schmorl's node were not related to disk pathologies(p > 0.05). In lumbar Scheuermann's disease, anterior Schmorl's node and decreased height of

  12. A CLINICAL STUDY OF OPERATIVE TREATMENT FOR LUMBAR INTERVERTEBRAL DISC PROLAPSE

    OpenAIRE

    Anilkumar S. D

    2016-01-01

    BACKGROUND Amongst painful diseases, sciatica occupies a foremost place by reason of its prevalence, its production by a great variety of conditions, the great disablement it may produce and its tending to relapse all of which have led to its recognition as one of the great scourges of humanity. Intervertebral disc prolapse is the important and common cause of low back pain and sciatica. Here, the subject of laminectomy and discectomy in the treatment of proven intervertebral disc...

  13. Cervical Total Disk Arthroplasty.

    Science.gov (United States)

    Roberts, Timothy T; Filler, Ryan J; Savage, Jason W; Benzel, Edward C

    2018-02-01

    In the United States, cervical total disk arthroplasty (TDA) is US Federal Drug Administration (FDA) approved for use in both 1 and 2-level constructions for cervical disk disease resulting in myelopathy and/or radiculopathy. TDA designs vary in form, function, material composition, and even performance in?vivo. However, the therapeutic goals are the same: to remove the painful degenerative/damaged elements of the intervertebral discoligamenous joint complex, to preserve or restore the natural range of spinal motion, and to mitigate stresses on adjacent spinal segments, thereby theoretically limiting adjacent segment disease (ASDis). Cervical vertebrae exhibit complex, coupled motions that can be difficult to artificially replicate. Commonly available TDA designs include ball-and-socket rotation-only prostheses, ball-and-trough rotation and anterior-posterior translational prostheses, as well as unconstrained elastomeric disks that can rotate and translate freely in all directions. Each design has its respective advantages and disadvantages. At this time, available clinical evidence does not favor 1 design philosophy over another. The superiority of cervical TDA over the gold-standard anterior cervical discectomy and fusion is a subject of great controversy. Although most studies agree that cervical TDA is at least as effective as anterior cervical discectomy and fusion at reducing or eliminating preoperative pain and neurological symptoms, the clinical benefits of motion preservation- that is, reduced incidence of ASDis-are far less clear. Several short-to-mid-term studies suggest that disk arthroplasty reduces the radiographic incidence of adjacent segment degeneration; however, the degree to which this is clinically significant is disputed. At this time, TDA has not been clearly demonstrated to reduce symptomatic?ASDis.

  14. Hernia of intervertebral disk in the lumbar vertebral column

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, H.K.; Uhlenbrock, D.; Steiner, G.

    1986-02-01

    Degenerations of the spinal disc especially in the lumbar region are the most frequent degenerative diseases in orthopedics. As diagnostic proceedings to discover disc herniation myelography and computerized tomography have been proven to be very useful. Each of those methods show a high sensitivity and accuracy. Computerized tomography seems to be the first procedure because of the lac of any risk. Myelography has been reserved for the second approach, if there is any doubt in diagnosis. This paper will especially discuss advantages and disadvantages of MRI-tomography for the diagnosis of disc herniation. In MRI-tomography we have no radiation, there is no risk for the patient and we have the possibility of slices in different orientations with the sagittal orientation having priority in diagnosis of disc herniation. A more pronounced contrast in MRI relatively to the computerized tomography with nearly the same spatial resolution is an other important fact in favour for MRI. The value of MRI diagnosis of the spine depends however mainly on the use of special surface coils and on the use of high magnetic fields which provides a good signal to noise relation and which would permit us to use a thin-slice technique. The main disadvantage by now are the relative high costs.

  15. Optimization of Spinal Anesthesia in Surgery of Intervertebral Disks

    Directory of Open Access Journals (Sweden)

    V. I. Gorbachev

    2006-01-01

    Full Text Available The paper gives the data of preoperative evaluation of autonomous nervous system tone and its correction, pharmacokinetics of local anesthetics in the subarachnoidal space, as well as the optimization of a procedure for spinal anesthesia in patients operated on for lumbosacral radiculitis. 

  16. Intervertebral Disk Disease in 3 Striped Skunks (Mephitis mephitis)

    NARCIS (Netherlands)

    Krauss, M.W.; Benato, L.; McDonnell, J.; Schoemaker, N.J.; Westerhof, I.; Bronson, E.; Gielen, I.; van Caelenberg, A.; Hellebuyck, T.; Meij, B.P.; de Decker, S.

    Objective To describe diagnostic findings, surgical technique, and outcome in 3 striped skunks (Mephitis mephitis) with a history of paraparesis. Study Design Case series. Animals Skunks (n = 3) with paraparesis. Methods Neurologic examination revealed upper motor neuron disease (T2–L2) in 2 skunks

  17. Intervertebral disc calcifications in children.

    Science.gov (United States)

    Beluffi, G; Fiori, P; Sileo, C

    2009-03-01

    This study was done to assess the presence of both asymptomatic and symptomatic intervertebral disc calcifications in a large paediatric population. We retrospectively reviewed the radiographs taken during the past 26 years in children (age 0-18 years) undergoing imaging of the spine or of other body segments in which the spine was adequately depicted, to determine possible intervertebral disc calcifications. The following clinical evaluation was extrapolated from the patients' charts: presence of spinal symptoms, history of trauma, suspected or clinically evident scoliosis, suspected or clinically evident syndromes, bone dysplasias, and pre- or postoperative chest or abdominal X-rays. We detected intervertebral disc calcifications in six patients only. Five calcifications were asymptomatic (one newborn baby with Patau syndrome; three patients studied to rule out scoliosis, hypochondroplasia and syndromic traits; one for dyspnoea due to sunflower seeds inhalation). Only one was symptomatic, with acute neck pain. Calcifications varied in number from one in one patient to two to five in the others. Apart from the calcification in the patient with cervical pain, all calcifications were asymptomatic and constituted an incidental finding (particularly those detected at the thoracic level in the patient studied for sunflower-seed inhalation). Calcification shapes were either linear or round. Our series confirms that intervertebral disc calcifications are a rare finding in childhood and should not be a source of concern: symptomatic calcifications tend to regress spontaneously within a short time with or without therapy and immobilisation, whereas asymptomatic calcifications may last for years but disappear before the age of 20 years. Only very few cases, such as those of medullary compression or severe dysphagia due to anterior herniation of cervical discs, may require surgical procedures.

  18. Galaxy Disks

    NARCIS (Netherlands)

    van der Kruit, P. C.; Freeman, K. C.

    The disks of disk galaxies contain a substantial fraction of their baryonic matter and angular momentum, and much of the evolutionary activity in these galaxies, such as the formation of stars, spiral arms, bars and rings, and the various forms of secular evolution, takes place in their disks. The

  19. Herniated Lumbar Disks: Real-time MR Imaging Evaluation during Continuous Traction.

    Science.gov (United States)

    Chung, Tae-Sub; Yang, Hea-Eun; Ahn, Sung Jun; Park, Jung Hyun

    2015-06-01

    To assess the morphologic changes in herniated lumbar intervertebral disks and surrounding structures during lumbar traction by using real-time magnetic resonance (MR) imaging. This prospective study was approved by the institutional review board, and written informed consent was obtained from all participants. Forty-eight consecutive patients with lumbar disk herniation (13 men and 35 women) were treated with continuous lumbar traction by using a nonmagnetic traction device. Real-time MR imaging of the lumbar spine was performed before the initiation of traction and at 10-minute intervals during 30 minutes of 30 kg of continuous traction. Sagittal and axial MR images were analyzed to determine qualitative changes during lumbar traction. Quantitative changes caused by traction on the lumbar spine were determined by measurement of lumbar vertebral column elongation and the disk reduction ratio. Continuous traction on herniated lumbar disks and surrounding structures resulted in change in disk shape, disk reduction with opening in the intervertebral disk, reduction of herniated disk volume, separation of the disk and adjoining nerve root, and widening of the facet joint. Both the mean lumbar vertebral column length (elongation of 1.45% after 30 minutes, P traction, respectively) increased with time of traction. The results of this study demonstrated that the real-time effects of continuous traction on herniated lumbar intervertebral disks and their surrounding structures can be visualized by using MR imaging. RSNA, 2015

  20. Magnetic resonance imaging of intervertebral disc degeneration

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Hiroshi; Noguchi, Masao (Kitakyushu City Yahata Hospital, Fukuoka (Japan)); Kira, Hideaki; Fujiki, Hiroshi; Shimokawa, Isao; Hinoue, Kaichi

    1993-02-01

    The aim of this study was to correlate the degree of lumbar intervertebral disc degeneration with findings of magnetic resonance imaging (MRI). Seventeen autopsied (from 7 patients) and 21 surgical (from 20 patients) intervertebral discs were used as specimens for histopathological examination. In addition, 21 intervertebral discs were examined on T2-weighted images. Histopathological findings from both autopsied and surgical specimens were well correlated with MRI findings. In particular, T2-weighted images reflected increased collagen fibers and rupture within the fibrous ring accurately. However, when severely degenerated intervertebral discs and hernia protruding the posterior longitudinal ligament existed, histological findings were not concordant well with T2-weighted images. Morphological appearances of autopsy specimens, divided into four on T2-weighted images, were well consistent with histological degeneration. This morphological classification, as shown on T2-weighted images, could also be used in the evaluation of intervertebral disc degeneration. (N.K.).

  1. Pseudoenhancement of intervertebral disc herniation

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Y.; Ootani, M.; Furukawa, T.; Tsukaguchi, I. (Dept. of Radiology, Osaka Rosai Hospital (Japan)); Mitomo, M. (Dept. of Radiology, Osaka Univ. Medical School (Japan))

    1992-08-01

    Two patients with intervertebral disc herniation appeared to demonstrate abnormally diffuse and intense enhancement of the disc after intravenous administration of gadolinium-DTPA for MRI. Surgery disclosed a dilated epidural venous plexus in one and vascular granulation tissue in the other, associated with the herniated disc material. The mechanism of this 'pseudoenhancement' of the disc appears to be a partial volume effect of disc material and the adjacent veins or granulation tissue. Pseudoenhancement of a herniated disc should be included in the differential diagnosis of a diffusely enhancing epidural mass. (orig.).

  2. On the relative relevance of subject-specific geometries and degeneration-specific mechanical properties for the study of cell death in human intervertebral disc models

    Directory of Open Access Journals (Sweden)

    Andrea eMalandrino

    2015-02-01

    Full Text Available Capturing patient- or condition-specific intervertebral disc (IVD properties in finite element models is outmost important in order to explore how biomechanical and biophysical processes may interact in spine diseases. However, disc degenerative changes are often modelled through equations similar to those employed for healthy organs, which might not be valid. As for the simulated effects of degenerative changes, they likely depend on specific disc geometries. Accordingly, we explored the ability of continuum tissue models to simulate disc degenerative changes. We further used the results in order to assess the interplay between these simulated changes and particular IVD morphologies, in relation to disc cell nutrition, a potentially important actor in disc tissue regulation. A protocol to derive patient-specific computational models from clinical images was applied to different spine specimens. In vitro IVD creep tests were used to optimize poro-hyperelastic input material parameters in these models, in function of the IVD degeneration grade. The use of condition-specific tissue model parameters in the specimen-specific geometrical models was validated against independent kinematic measurements in vitro. Then, models were coupled to a transport-cell viability model in order to assess the respective effects of tissue degeneration and disc geometry on cell viability. While classic disc poromechanical models failed in representing known degenerative changes, additional simulation of tissue damage allowed model validation and gave degeneration-dependent material properties related to osmotic pressure and water loss, and to increased fibrosis. Surprisingly, nutrition-induced cell death was independent of the grade-dependent material properties, but was favoured by increased diffusion distances in large IVDs. Our results suggest that in situ geometrical screening of IVD morphology might help to anticipate particular mechanisms of disc degeneration.

  3. Progranulin derived engineered protein Atsttrin suppresses TNF-α-mediated inflammation in intervertebral disc degenerative disease.

    Science.gov (United States)

    Ding, Hong; Wei, Jianlu; Zhao, Yunpeng; Liu, Yi; Liu, Lian; Cheng, Lei

    2017-12-12

    Atsttrin, an engineered molecule composed of three fragments of progranulin(PGRN), exerts comparable anti-inflammation ability. Intervertebral disc degeneration (IDD) is involved in inflammation in which TNF-α plays a key role. This study aims to examine the effect and the mechanism of Atsttrin in the pathogenesis of intervertebral disc degeneration. For this purpose, we took advantage of murine and human intervertebral disc (IVD) and examined the expression of TNF-α in IVD tissues using immunohistochemistry and TNF-α level in peripheral sera by ELISA assay. Moreover, murine IVD was taken to undergo the Safranin O and HE staining. Furthermore, primary human nucleus pulposus cells were used for immunohistochemistry staining, fluorescent staining, Western Blot, ELISA assay and RT-PCR assay. Herein we found TNF-α expression was elevated in intervertebral disc and peripheral sera in patients with IDD. Interestingly, Atsttrin effectively inhibited TNF-α-mediated catabolism in murine disc by ex vivo study. TNF-α-induced inflammatory cytokines were strongly reduced in presence of Atsttrin in primary human disc. Mechanism study indicated Atsttrin protected against intervertebral disc degeneration by inhibiting TNF-α-induced inflammation. These findings show that Atsttrin is a potential molecular target for disc degenerative diseases.

  4. Analysis Of 1058 Lumbar Prolapsed Intervertebral Disc Cases In Two Tertiary Care Hospitals Of Pakistan.

    Science.gov (United States)

    Junaid, Muhammad; Rashid, Mamoon Ur; Afsheen, Afeera; Bukhari, Syed Sarmad; Kalsoom, Anisa

    2016-01-01

    Characteristics of Prolapsed Intervertebral Disc (PID) in two tertiary care hospitals of Pakistan. The objective of this was to study the demographic characteristics of lumbar PID by age, gender, clinical presentation, levels of spinal column involvement, treatment options and post-operative complications for lumber disc prolapse. One thousand and fifty eight cases (708 males, 350 females) of prolapsed intervertebral disc over six years between January 2009 and December 2014 were studied for location of prolapsed disks, gender, age, clinical presentation, treatment options and complications of surgery. Of the determined locations L5/S1 was the commonest (34.6%), followed by L4/L5 (33.4%). 24.2%of the patients had prolapsed disks at 2 levels (L3/L4, L4/L5 andL4/L5, L5/S1). Prolapsed disc was commonest in the 31-49 year age group. Male were mostly affected with male to female ratio of 2.02%. Most common surgery performed was discectomy with fenestration (60.64% of total surgeries performed) and most common postoperative complication being mechanical backache (4.8%). Prolapsed intervertebral disc is common in the lower lumbar region at the level of L4/L5 and L5/S1. The outcome of the patients who underwent surgery is very good with 92.19% of patients, being free of postoperative complications.

  5. Microendoscopic discectomy for prolapsed lumbar intervertebral disc

    OpenAIRE

    Ranjan Alok; Lath Rahul

    2006-01-01

    Background: Lumbar disc prolapse is a common problem and the current surgical standard for its treatment is a microsurgical discectomy. Microendoscopic discectomy (MED) is a minimally invasive spinal procedure being done successfully for prolapsed intervertebral disc disease. Aims: We report the technique, outcome and complications seen in 107 cases of prolapsed lumbar intervertebral disc who underwent MED. Setting and Design: The study was carried out at the Department of Neurosurgery, ...

  6. Regression of lumbar disk herniation

    Directory of Open Access Journals (Sweden)

    G. Yu Evzikov

    2015-01-01

    Full Text Available Compression of the spinal nerve root, giving rise to pain and sensory and motor disorders in the area of its innervation is the most vivid manifestation of herniated intervertebral disk. Different treatment modalities, including neurosurgery, for evolving these conditions are discussed. There has been recent evidence that spontaneous regression of disk herniation can regress. The paper describes a female patient with large lateralized disc extrusion that has caused compression of the nerve root S1, leading to obvious myotonic and radicular syndrome. Magnetic resonance imaging has shown that the clinical manifestations of discogenic radiculopathy, as well myotonic syndrome and morphological changes completely regressed 8 months later. The likely mechanism is inflammation-induced resorption of a large herniated disk fragment, which agrees with the data available in the literature. A decision to perform neurosurgery for which the patient had indications was made during her first consultation. After regression of discogenic radiculopathy, there was only moderate pain caused by musculoskeletal diseases (facet syndrome, piriformis syndrome that were successfully eliminated by minimally invasive techniques. 

  7. [Imaging study of lumbar intervertebral disc herniation and asymptomatic lumbar intervertebral disc herniation].

    Science.gov (United States)

    Yu, Qing-yang; Yang, Cun-rui; Yu, Lang-tao

    2009-04-01

    Using regional assignment to forked method to study lumbar intervertebral disc hemiation (bugle, hernia, prolapse) dependablity and reason of lumbar intervertebral disc herniation and asymptomatic lumbar intervertebral disc herniation. From March 2005 to October 2006, 120 patients of match condition from orthopaedics dept and rehabilitative dept of the Boai hospital of Longyan were studied. All patients were equally divided into two groups according to whether or not accompany with symptom of lumbar intervertebral disc herniation. There was not statistical difference in sex, age, course of disease, segment of intervertebral disc between two groups. Sixty patients of symptomatic lumbar intervertebral disc herniation were equally divided into three groups according to (bugle, hernia, prolapse) image on CT. Sixty patients of asymptomatic lumbar intervertebral disc herniation were equally divided into three groups according to (bugle, hernia, prolapse) image on CT. The age was 20-59 years old with an average of 38.5 years. Using regional assignment to give a mark respectively for every group. The sagittal diameter index (SI), anterior diastema of flaval ligaments, the width of superior outlet of latero-crypt, anteroposterior diameter of dura sac were respectively measured by sliding caliper. CT value and protrusible areas were respectively evaluated by computer tomography. Adopting mean value to measure three times. (1) There were not statistical difference in SI, CT value, hernia areas, anteroposterior diameter of dura sac between two groups (symptomatic lumbar intervertebral disc herniation and asymptomatic lumbar intervertebral disc herniation). There were statistical difference in the width of superior outlet of latero-crypt, anterior diastema of flaval ligaments between two groups (symptomatic lumbar intervertebral disc herniation and asymptomatic lumbar intervertebral disc herniation). (2) There were statistical difference in protrusible type,protrusible segment

  8. Spectroscopic Parameters of Lumbar Intervertebral Disc Material

    Science.gov (United States)

    Terbetas, G.; Kozlovskaja, A.; Varanius, D.; Graziene, V.; Vaitkus, J.; Vaitkuviene, A.

    2009-06-01

    There are numerous methods of investigating intervertebral disc. Visualization methods are widely used in clinical practice. Histological, imunohistochemical and biochemical methods are more used in scientific research. We propose that a new spectroscopic investigation would be useful in determining intervertebral disc material, especially when no histological specimens are available. Purpose: to determine spectroscopic parameters of intervertebral disc material; to determine emission spectra common for all intervertebral discs; to create a background for further spectroscopic investigation where no histological specimen will be available. Material and Methods: 20 patients, 68 frozen sections of 20 μm thickness from operatively removed intervertebral disc hernia were excited by Nd:YAG microlaser STA-01-TH third harmonic 355 nm light throw 0, 1 mm fiber. Spectrophotometer OceanOptics USB2000 was used for spectra collection. Mathematical analysis of spectra was performed by ORIGIN multiple Gaussian peaks analysis. Results: In each specimen of disc hernia were found distinct maximal spectral peaks of 4 types supporting the histological evaluation of mixture content of the hernia. Fluorescence in the spectral regions 370-700 nm was detected in the disc hernias. The main spectral component was at 494 nm and the contribution of the components with the peak wavelength values at 388 nm, 412 nm and 435±5 nm were varying in the different groups of samples. In comparison to average spectrum of all cases, there are 4 groups of different spectral signatures in the region 400-500 nm in the patient groups, supporting a clinical data on different clinical features of the patients. Discussion and Conclusion: besides the classical open discectomy, new minimally invasive techniques of treating intervertebral disc emerge (PLDD). Intervertebral disc in these techniques is assessed by needle, no histological specimen is taken. Spectroscopic investigation via fiber optics through the

  9. Curcuma DMSO extracts and curcumin exhibit an anti-inflammatory and anti-catabolic effect on human intervertebral disc cells, possibly by influencing TLR2 expression and JNK activity

    Science.gov (United States)

    2012-01-01

    Background As proinflammatory cytokines seem to play a role in discogenic back pain, substances exhibiting anti-inflammatory effects on intervertebral disc cells may be used as minimal-invasive therapeutics for intradiscal/epidural injection. The purpose of this study was to investigate the anti-inflammatory and anti-catabolic potential of curcuma, which has been used in the Indian Ayurvedic medicine to treat multiple ailments for a long time. Methods Human disc cells were treated with IL-1β to induce an inflammatory/catabolic cascade. Different extracts of curcuma as well as curcumin (= a component selected based on results with curcuma extracts and HPLC/MS analysis) were tested for their ability to reduce mRNA expression of proinflammatory cytokines and matrix degrading enzymes after 6 hours (real-time RT-PCR), followed by analysis of typical inflammatory signaling mechanisms such as NF-κB (Western Blot, Transcription Factor Assay), MAP kinases (Western Blot) and Toll-like receptors (real-time RT-PCR). Quantitative data was statistically analyzed using a Mann Whitney U test with a significance level of p curcuma DMSO extract significantly reduced levels of IL-6, MMP1, MMP3 and MMP13. The DMSO-soluble component curcumin, whose occurrence within the DMSO extract was verified by HPLC/MS, reduced levels of IL-1β, IL-6, IL-8, MMP1, MMP3 and MMP13 and both caused an up-regulation of TNF-α. Pathway analysis indicated that curcumin did not show involvement of NF-κB, but down-regulated TLR2 expression and inhibited the MAP kinase JNK while activating p38 and ERK. Conclusions Based on its anti-inflammatory and anti-catabolic effects, intradiscal injection of curcumin may be an attractive treatment alternative. However, whether the anti-inflammatory properties in vitro lead to analgesia in vivo will need to be confirmed in an appropriate animal model. PMID:22909087

  10. Microendoscopic discectomy for prolapsed lumbar intervertebral disc.

    Science.gov (United States)

    Ranjan, Alok; Lath, Rahul

    2006-06-01

    Lumbar disc prolapse is a common problem and the current surgical standard for its treatment is a microsurgical discectomy. Microendoscopic discectomy (MED) is a minimally invasive spinal procedure being done successfully for prolapsed intervertebral disc disease. We report the technique, outcome and complications seen in 107 cases of prolapsed lumbar intervertebral disc who underwent MED. The study was carried out at the Department of Neurosurgery, at a tertiary hospital in South India and the data was collected prospectively. 107 patients with prolapsed lumbar intervertebral disc who were seen at our institution between November 2002 and January 2006 were included in the study. Data was collected prospectively. The METRx system (Medtronic Sofamor Danek, Memphis,TN) was used to perform MED. Outcome assessment was done by the modified Macnab criteria. 107 patients (67 males, 40 females) underwent MED for prolapsed lumbar intervertebral disc. Follow up ranged from 2 to 40 months with a mean follow up 12.9 months. Seventy six patients had an excellent outcome, 22 patients had a good outcome, 5 patients had a fair outcome and 3 patients had a poor outcome. One patient with a long dural tear required conversion to a standard microdiscectomy and was excluded from outcome assessment. Complications included dural puncture with K-wire (1), dural tear (2), superficial wound infection (1), discitis (1) and recurrent disc prolapse (2). Microendoscopic Discectomy (MED) is a safe and effective procedure for the treatment of prolapsed lumbar intervertebral disc.

  11. -How does one question a patient who is suffering still after lumbar disk surgery, before using computed tomography or MRI of the spine?-.

    Science.gov (United States)

    Wybier, M; Parlier, C; Champsaur, P; Laredo, J D

    1997-01-01

    Interrogation of patients still painful after lumbar intervertebral disk surgery provides with a series of informations each of them having only an indicative value, while they altogether compound a score helping assess the presence or the absence of a recurring disk herniation.

  12. [Research advances in animal models of intervertebral disc degeneration].

    Science.gov (United States)

    Zhang, Wenli; Liu, Hao; Li, Tanzhu

    2007-11-01

    To review the research advances in animal models of human disc degeneration. The relative articles in recent years were extensively reviewed. Studies both at home and abroad were analyzed and classified. The advantages and disadvantages of each method were compared. Studies were classified as either experimentally induced models or spontaneous models. The induced models were subdivided as mechanical (alteration of forces on the normal disc), structural (injury or chemical alteration) and genetically induced models. Spontaneous models included those animals that naturally developed degenerative disc disease. Animal model of intervertebral disc degeneration is an important path for revealing the pathogenesis of human disc degeneration, and play an important role in testing novel interventions. With recent advances in the relevance of animal models and humans, it has a great prospect in study of human disc degeneration.

  13. Relationship between Initial Telomere Length, Initial Telomerase Activity, Age, and Replicative Capacity of Nucleus Pulposus Chondrocytes in Human Intervertebral Discs: What Is a Predictor of Replicative Potential?

    Science.gov (United States)

    Lee, Jun-Seok; Jeong, Seo-Won; Cho, Sung-Wook; Juhn, Joon-Pyo; Kim, Ki-Won

    2015-01-01

    There is evidence that telomere length (TL), telomerase activity (TA), and age are related to the replicative potential of human nucleus pulposus chondrocytes (NPCs). However, it has not yet been established if any of these factors can serve as predictors of the replicative potential of NPCs. To establish predictors of the replicative potential of NPCs, we evaluated potential relationships between replicative capacity of NPCs, initial TL (telomere length at the first passage), initial TA (telomerase activity at the first passage), and age. Nucleus pulposus specimens were obtained from 14 patients of various ages undergoing discectomy. NPCs were serially cultivated until the end of their replicative lifespans. Relationships among cumulative population doubling level (PDL), initial TL, initial TA, and age were analyzed. Initial TA was negatively correlated with age (r = -0.674, P = 0.008). However, no correlation between initial TL and age was observed. Cumulative PDL was also negatively correlated with age (r = -0.585, P = 0.028). Although the cumulative PDL appeared to increase with initial TL or initial TA, this trend was not statistically significant. In conclusion, age is the sole predictor of the replicative potential of human NPCs, and replicative potential decreases with age. Initial TL and initial TA are not predictors of replicative potential, and can serve only as reference values.

  14. Engineering alginate for intervertebral disc repair

    NARCIS (Netherlands)

    Bron, Johannes L.; Vonk, Lucienne A.; Smit, Theodoor H.; Koenderink, Gijsje H.

    2011-01-01

    Alginate is frequently studied as a scaffold for intervertebral disc (IVD) repair, since it closely mimics mechanical and cell-adhesive properties of the nucleus pulposus (NP) of the IVD. The aim of this study was to assess the relation between alginate concentration and scaffold stiffness and find

  15. Intervertebral disc herniation: prevalence and association with ...

    African Journals Online (AJOL)

    Background: Low back pain is one of the common health problems encountered in life with intervertebral disc herniation being a common cause of its occurrence. Magnetic resonance imaging has emerged the gold standard for diagnosing a herniated disc. Aims and Objectives: To assess the frequency and pattern of ...

  16. Can Exercise Positively Influence the Intervertebral Disc?

    NARCIS (Netherlands)

    Belavý, Daniel L.; Albracht, Kirsten; Bruggemann, Gert Peter; Vergroesen, Pieter Paul A; van Dieën, Jaap H.

    2016-01-01

    To better understand what kinds of sports and exercise could be beneficial for the intervertebral disc (IVD), we performed a review to synthesise the literature on IVD adaptation with loading and exercise. The state of the literature did not permit a systematic review; therefore, we performed a

  17. Inflammatory profiles in canine intervertebral disc degeneration

    NARCIS (Netherlands)

    Willems, Nicole; Tellegen, Anna R.; Bergknut, Niklas; Creemers, Laura B.; Wolfswinkel, Jeannette; Freudigmann, Christian; Benz, Karin; Grinwis, Guy C M; Tryfonidou, Marianna A.; Meij, Björn P.

    2016-01-01

    BACKGROUND: Intervertebral disc (IVD) disease is a common spinal disorder in dogs and degeneration and inflammation are significant components of the pathological cascade. Only limited studies have studied the cytokine and chemokine profiles in IVD degeneration in dogs, and mainly focused on gene

  18. Lumbar disk herniation: do MR imaging findings predict recurrence after surgical diskectomy?

    Science.gov (United States)

    Dora, Claudio; Schmid, Marius R; Elfering, Achim; Zanetti, Marco; Hodler, Juerg; Boos, Norbert

    2005-05-01

    To retrospectively evaluate if the degree of disk degeneration and disk herniation volume at magnetic resonance (MR) imaging are risk factors for recurrent disk herniation. The institutional review board permits such retrospective studies, and individual informed consent was not required. MR imaging findings obtained before initial diskectomy in 30 patients (mean age, 42.8 years; 10 women, 20 men) with recurrent disk herniation (study group) and 30 patients (mean age, 42.2 years; nine women, 21 men) without recurrence for at least 2 years after surgery (control group) were compared. Disk degeneration was assessed on T2-weighted sagittal MR images with a five-point grading system (grade I indicated no degeneration; grade II, horizontal hypointense bands within disk; grade III, inhomogeneous disk with intermediate signal intensity; grade IV, no distinction between inner and outer parts of disk; and grade V, collapsed hypointense disk). Disk herniation was classified as representing protrusion, extrusion, or sequestration. The volume of both the affected intervertebral disk and the herniated disk material was measured. Qualitative and quantitative analyses were performed by two readers. The chi(2) test was used for comparison of categorical variables. For comparison of disk degeneration and volumes between patients with and those without recurrence, a paired two-tailed t test was used. Odds ratios based on the extent of disk degeneration were calculated for the entire sample. Advanced disk degeneration (grades IV and V) was significantly less frequent in the study group than in the control group (P < .006). The risk of recurrent disk herniation decreased by a factor of 3.4 for each increase in grade of disk degeneration (odds ratio: 3.58; 95% confidence interval: 1.3, 9.6; P = .011). Mean disk herniation volume as a percentage of intervertebral disk volume was 10.59% +/- 3.41 in the study group and 11.56% +/- 3.84 in the control group. This difference was not

  19. Cell therapy for the degenerating intervertebral disc.

    Science.gov (United States)

    Tong, Wei; Lu, Zhouyu; Qin, Ling; Mauck, Robert L; Smith, Harvey E; Smith, Lachlan J; Malhotra, Neil R; Heyworth, Martin F; Caldera, Franklin; Enomoto-Iwamoto, Motomi; Zhang, Yejia

    2017-03-01

    Spinal conditions related to intervertebral disc (IVD) degeneration cost billions of dollars in the US annually. Despite the prevalence and soaring cost, there is no specific treatment that restores the physiological function of the diseased IVD. Thus, it is vital to develop new treatment strategies to repair the degenerating IVD. Persons with IVD degeneration without back pain or radicular leg pain often do not require any intervention. Only patients with severe back pain related to the IVD degeneration or biomechanical instability are likely candidates for cell therapy. The IVD progressively degenerates with age in humans, and strategies to repair the IVD depend on the stage of degeneration. Cell therapy and cell-based gene therapy aim to address moderate disc degeneration; advanced stage disease may require surgery. Studies involving autologous, allogeneic, and xenogeneic cells have all shown good survival of these cells in the IVD, confirming that the disc niche is an immunologically privileged site, permitting long-term survival of transplanted cells. All of the animal studies reviewed here reported some improvement in disc structure, and 2 studies showed attenuation of local inflammation. Among the 50 studies reviewed, 25 used some type of scaffold, and cell leakage is a consistently noted problem, though some studies showed reduced cell leakage. Hydrogel scaffolds may prevent cell leakage and provide biomechanical support until cells can become established matrix producers. However, these gels need to be optimized to prevent this leakage. Many animal models have been leveraged in this research space. Rabbit is the most frequently used model (28 of 50), followed by rat, pig, and dog. Sheep and goat IVDs resemble those of humans in size and in the absence of notochordal cells. Despite this advantage, there were only 2 sheep and 1 goat studies of 50 studies in this cohort. It is also unclear if a study in large animals is needed before clinical trials since

  20. EVALUATION OF TERMINAL VERTEBRAL PLATE ON CERVICAL SPINE AT DIFFERENT AGE GROUPS AND ITS CORRELATION WITH INTERVERTEBRAL DISC THICKNESS.

    Science.gov (United States)

    Luiz Vieira, Juliano Silveira; da Silva Herrero, Carlos Fernando Pereira; Porto, Maximiliano Aguiar; Nogueira Barbosa, Marcello Henrique; Garcia, Sérgio Britto; Zambelli Ramalho, Leandra Náira; Aparecido Defino, Helton Luiz

    2009-01-01

    To evaluate, by means of histomorphometry, terminal vertebral plate thickness, intervertebral disc thickness and its correlation on different age groups, seeking to identify its correlation. C4-C5 and C5-C6 cervical segments removed from human cadavers of both genders were assessed and divided into five groups of 10-year age intervals, from 21 years old. TVP and intervertebral disc thickness evaluation was made by means of histomorphometry of histological slides stained with hematoxylin and eosyn. Lower C4 TVP, upper C5 TVP, and upper C6 TVP de were compared between each other and to the interposed intervertebral disc thickness between relevant TVP. The thickness of terminal vertebral plates adjacent to the same ID did not show statistic differences. However, the comparison of upper and lower vertebral plates thickness on the same cervical vertebra (C5), showed statistical difference on all age groups studied. We found a statistical correlation coefficient above 80% between terminal vertebral plate and adjacent intervertebral disc, with a proportional thickness reduction of both structures on the different cervical levels studied, and also on the different age groups assessed. Terminal vertebral plate shows a morphologic correlation with the intervertebral disc next to it, and does not show correlation with the terminal vertebral plate on the same vertebra.

  1. Analysis of trace element in intervertebral disc by Atomic Absorption Spectrometry techniques in degenerative disc disease in the Polish population

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    Andrzej Nowakowski

    2015-05-01

    Full Text Available Objective. Although trace elements are regarded crucial and their content has been determined in number of tissue there are only few papers addressing this problem in intervertebral disc in humans. Most of the trace elements are important substrates of enzymes influencing metabolism and senescence process. Others are markers of environmental pollution. Therefore the aim of the research was to analyzed of the trace element content in the intervertebral disc, which may be a vital argument recognizing the background of degenerative changes to be the effect of the environment or metabolic factors. Materials and methods. Material consist of 18 intervertebral disc from 15 patients, acquired in surgical procedure of due to the degenerative disease with Atomic Absorption Spectrometry content of Al, Cd, Co, Pb, Cu, Ni, Mo, Mg, Zn was evaluated. Results. Only 4 of the trace elements were detected in all samples. The correlation analysis showed significant positive age correlation with Al and negative in case of Co. Among elements significant positive correlation was observed between Al/Pb, Co/Mo, Al/Mg, Al/Zn Pb/Zn and Mg/Zn. Negative correlation was observed in Al/Co, Cd/Mg, Co/Mg, Mo/Mg, Co/Zn and Mo/Zn. Conclusions. This study is the first to our knowledge that profiles the elements in intervertebral disc in patients with degenerative changes. We have confirmed significant differences between the trace element contents in intervertebral disc and other tissue. It can be ground for further investigation.

  2. Dynamic mobilisations in cervical flexion: Effects on intervertebral angulations.

    Science.gov (United States)

    Clayton, H M; Kaiser, L J; Lavagnino, M; Stubbs, N C

    2010-11-01

    Based upon human data, it is probable that many conditions associated with neck pain in horses may benefit from performing mobilisation exercises as part of the rehabilitation protocol. To compare sagittal plane intervertebral angulations in a neutral standing position with the angulations at end range of motion in 3 dynamic mobility exercises performed in cervical flexion. Sagittal plane motion of the head, neck and back were measured in 8 sound horses standing in a neutral position and in 3 end-of-range neck flexion positions: chin-to-chest, chin-between-carpi, and chin-between-fore fetlocks. Skin markers on the head, transverse processes of C1-C6, and dorsal spinous processes of T6, T8, T10, T16, L2, L6, S2 and S4 were tracked and adjacent markers connected to form rigid segments. Intersegmental angles, measured between segments on the ventral surface, in the 4 positions were compared using repeated measures ANOVA with Bonferroni post hoc tests (Pneck. The angle at C1 was significantly more extended for chin-between-carpi (98 ± 11°) and chin-between-fetlocks (132 ± 11°) than for the neutral position (86 ± 8°) or chin-to-chest (92 ± 8°) positions. The intersegmental angle at C6 indicated progressive lowering of the neck from neutral through chin-to-chest and chin-between-carpi to chin-between-fetlocks. The intersegmental angles from T6-L1 were more flexed by 3-7° in the cervical flexions compared with the neutral position with the differences being significant for at least one of the dynamic mobilisations at each vertebral level. The articulations at the extremities of the cervical vertebral column are primarily responsible for sagittal plane position and orientation of the head and neck. Dynamic cervical flexion also flexes the thoracic intervertebral joints. The results indicate that dynamic mobilisation exercises performed in cervical flexion have applications in mobilising the cervical and thoracic intervertebral joints, which may have some clinical

  3. A method for quantitative measurement of lumbar intervertebral disc structures

    DEFF Research Database (Denmark)

    Tunset, Andreas; Kjær, Per; Samir Chreiteh, Shadi

    2013-01-01

    There is a shortage of agreement studies relevant for measuring changes over time in lumbar intervertebral disc structures. The objectives of this study were: 1) to develop a method for measurement of intervertebral disc height, anterior and posterior disc material and dural sac diameter using MRI...

  4. A slowly progressive and reproducible animal model of intervertebral disc degeneration characterized by MRI, X-ray, and histology.

    Science.gov (United States)

    Sobajima, Satoshi; Kompel, John F; Kim, Joseph S; Wallach, Corey J; Robertson, Douglas D; Vogt, Molly T; Kang, James D; Gilbertson, Lars G

    2005-01-01

    The progression of intervertebral disc degeneration following anterolateral "stab" of adult rabbit lumbar discs by 16-gauge hypodermic needle to a limited (5-mm) depth was studied for up to 24 weeks using magnetic resonance imaging, radiograph, and histologic outcome measures. To develop a slowly progressive, reproducible rabbit model of intervertebral disc degeneration suitable for studying pathogenesis and pathophysiology of intervertebral disc degeneration and testing safety and efficacy of novel approaches to the treatment of intervertebral disc degeneration (e.g., growth factors, gene therapy, cell therapy, and tissue engineering). Numerous animal models of intervertebral disc degeneration have been proposed in the literature, each with attendant advantages and disadvantages. The classic "stab model," involving full-thickness stab of anterior anulus fibrosus of adult rabbit lumbar discs by a number 11 scalpel blade, appears to produce changes in certain biochemical and histologic outcome measures that are similar to changes seen in human intervertebral disc degeneration. However, the immediate herniation of nucleus pulposus on full-thickness stab renders this model less suitable for 1) studying effects of less precipitous changes in nucleus pulposus and anulus fibrosus that may be important in the onset and progression of intervertebral disc degeneration and 2) testing novel therapeutic approaches that target the processes of early intervertebral disc degeneration. The L2-L3, L3-L4, and L4-L5 lumbar intervertebral discs of 18 skeletally mature female New Zealand White rabbits were stabbed by 16-gauge hypodermic needle to a depth of 5 mm in the left anterolateral anulus fibrosus. Serial magnetic resonance imaging scans of the stabbed discs and intact L1-L2 and L5-L6 control discs were performed at 3, 6, 12, and 24 weeks post surgery and compared with preoperative magnetic resonance images. Supplemental radiograph and histologic analyses were performed. The

  5. Influence of degenerative changes of intervertebral disc

    Directory of Open Access Journals (Sweden)

    WANG Yi

    2012-04-01

    Full Text Available 【Abstract】Objective: To investigate the material properties of normal and degenerated intervertebral discs (IVDs and examine the effect of degenerative changes on IVD pathology. Methods: A computer-based online search was under-taken to identify English articles about material properties of IVDs published from January 1950 to 2011 in PubMed database. The retrieved keywords included material properties, intervertebral disc and degeneration. Based on the principles of reliability, advancement and efficiency, the obtained data were primarily examined, and the original source was retrieved to read the full-text. Repetitive articles were excluded. The data of material properties of normal and degenerated IVDs were summarized and analyzed by meta-analysis. Results: The data of Young's modulus, Poisson's ratio, shear modulus, hydraulic permeability and intradiscal pres-sure of normal and degenerated IVDs were obtained. Com-pared with normal IVDs, the Young's modulus and shear modulus of annulus fibrosus and nucleus pulposus were higher in degenerated IVDs, the Poisson's ratio was lower while the hydraulic permeability and intradiscal pressure were higher. Besides, the degeneration-related alterations in IVDs had an influence both on itself and other spinal structures, leading to diseases such as bulging disc, discogenic pain and spinal stenosis. Meanwhile, the heavy mechanical loading and injury indicated important pathways to IVD degeneration. Conclusions: To a certain extent, the degenerative changes of IVD influence its material properties. And the degeneration-related alterations of composition can cause structural failure of IVDs, leading to injuries and diseases. Key words: Intervertebral disc; Mechanical phenomena; Degeneration; Elastic modulus; Permeability; Pathology

  6. Modelización del disco intervertebral

    OpenAIRE

    Campo i Mombiela, Oriol

    2008-01-01

    Con la intención de obtener más información sobre el comportamiento biomecánico de la columna vertebral y conocer así más a fondo las causas del dolor de espalda, se ha intentado modelizar por elementos finitos un disco intervertebral degenerado. En un inicio se realizo ensayos mecánicos a un disco proveniente de un cadáver varón de 75 años que como principal degeneración presenta osteochondrosis. Estos ensayos mecánicos pretenden reproducir los esfuerzos sufridos en la columna...

  7. Cells and Biomaterials for Intervertebral Disc Regeneration

    CERN Document Server

    Grad, Sibylle

    2010-01-01

    Disorders related to the intervertebral disc (IVD) are common causes of morbidity and of severe life quality deterioration. IVD degeneration, although in many cases asymptomatic, is often the origin of painful neck and back diseases. In Western societies IVD related pain and disability account for enormous health care costs as a result of work absenteeism and thus lost production, disability benefits, medical and insurance expenses. Although only a small percentage of patients with disc disorders finally will undergo surgery, spinal surgery has been one of the fastest growing disciplines in th

  8. A CLINICAL STUDY OF OPERATIVE TREATMENT FOR LUMBAR INTERVERTEBRAL DISC PROLAPSE

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    Anilkumar S. D

    2016-09-01

    Full Text Available BACKGROUND Amongst painful diseases, sciatica occupies a foremost place by reason of its prevalence, its production by a great variety of conditions, the great disablement it may produce and its tending to relapse all of which have led to its recognition as one of the great scourges of humanity. Intervertebral disc prolapse is the important and common cause of low back pain and sciatica. Here, the subject of laminectomy and discectomy in the treatment of proven intervertebral disc prolapse in the lower lumbar region is reviewed and its results examined. AIM OF STUDY This study was undertaken in order to evaluate the following objectives. PRIMARY Analysis of clinical parameters and per operative findings of lumbar intervertebral disc prolapse. SECONDARY Analysis of clinical parameters and surgical outcome in lumbar intervertebral disc prolapse with respect to improvement in pain and neurological status. MATERIALS AND METHODS The study was undertaken in 22 patients who attended the Orthopaedic Department of Mount Zion Medical College, Adoor, between August 2014 to July 2015. All of them were suffering from a prolapsed lumbar vertebral disc as shown by clinical examination and investigations. Lumbar laminectomy and discectomy constituted the operative procedure for all of them. RESULTS In acute onset cases and cases with short duration, results were good. By six months, 80% of patients recorded of good pain relief, 80% of patients returned to work within six 6 months, 60% of patients showed good neurological recovery by 6 months. Laminectomy and discectomy in proven cases of lumbar intervertebral disc prolapse is a rewarding procedure. LT definitely relieved pain in all cases and improved morbidity and neurological deficits in most of the cases. CONCLUSION 1. Laminectomy and discectomy is an effective method of treatment in herniation of lumbar intervertebral disc. 2. The procedure is ideally done in those with the disc prolapse proved with the

  9. Estudo comparativo dos mecanorreceptores dos discos intervertebrais normais e degenerados da coluna lombar de humanos pela radiografia, ressonância magnética e estudo anatomopatológico Comparative study of normal and degenerated intervertebral discs' mechanoreceptors of human lumar spine X-ray, magnetic resonance and anatomopathologic study

    Directory of Open Access Journals (Sweden)

    Valdeci Manoel de Oliveira

    2007-01-01

    Full Text Available Os autores fizeram um estudo da coluna lombar de humanos, objetivando avaliar e determinar os diferentes tipos de fibras nervosas no disco intervertebral normal e no degenerado. Foram usadas dez colunas lombares de cadáveres com aproximadamente 48 a 72 horas de óbito. As peças foram submetidas a exames de radiografia simples e ressonância magnética. Após os exames, os discos foram classificados em normais e degenerados. Em seguida, foram dissecados, divididos em regiões anterior e posterior, incluídos em parafina e realizado estudo de imuno-histoquímica com a proteína S100. Com o auxílio de um programa de computador Image-Pro Plus (media cybernetics®, as fibras nervosas tiveram seu diâmetro medidos em micrômetros e classificadas em quatro tipos de fibras. Foram encontrados quatro tipos de fibras nervosas nas diferentes regiões discais. O número e o tipo de fibras variaram de acordo com a região e grau de degeneração do disco intervertebral. Concluíram que as fibras do tipo III são mais freqüentes na região anterior; as fibras dos tipos II e IV são mais freqüentes na região posterior, e as fibras do tipo I não apresentaram diferenças entre a região anterior e a posterior; além disso, o disco degenerado tem mais fibras nervosas que o disco normal.The authors conducted a study on human lumbar spine, aiming to assess and determine the different kinds of nervous fibers in normal and degenerated intervertebral discs. Ten cadaver’s lumbar spines with approximately 48 - 72 of death have been used. The pieces were submitted to simple X-ray and magnetic resonance tests. Subsequently to the tests, discs were divided into normal and degenerated. Then, they were dissected, divided into anterior and posterior according to the region, included in paraffin and an immunohistochemical study with S100 protein was performed. With the aid of Image-Pro Plus computer software (media cybernetics ®, nervous fibers’ diameters were

  10. Intervertebral Disc Characteristic on Progressive Neurological Deficit

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    Farid Yudoyono

    2017-09-01

    Full Text Available Objective: To examine the intervertebral disc characteristic on magnetic resonance imaging (MRI in lumbar herniated disc (LHD patients with progressive neurological deficit. Methods: Patients were collected retrospectively from Dr. Hasan Sadikin General Hospital Database from 2011–2013 with LHD, had neurological deficit such as radiculopathy and cauda equine syndrome for less than four weeks with a positive sign confirmed by neurological examination and confirmatory with MRI examination. Results: A total of 14 patients with lumbar herniated disc disease (10 males, 4 females suffered from progressive neurological deficit with an average age of (52.07±10.9 years old. Early disc height was 9.38±0.5 mm and progressive neurological deficit state disc height was 4.03±0.53 mm, which were significantly different statisticaly (p<0.01. Symptoms of radiculopathy were seen in 11 patients and cauda equine syndrome in three patients. Modic changes grade 1 was found in five patients, grade 2 in eight patients,grade 3 in one patient, Pfirmman grade 2 in eleven patients and grade 3 in three patients. Thecal sac compression 1/3 compression was seen in four patients and 2/3 compression in ten patients. Conclusions: Neurosurgeon should raise concerns on the characteristic changes of intervertebral disc in magnetic resonance imaging examination to avoid further neural injury in lumbar herniated disc patients.

  11. INTERVERTEBRAL SIZE MEASUREMENT WITH ANTHROPOMETRIC METHOD

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    Zmago Turk

    2004-04-01

    Full Text Available Background. There is a positive correlation between the size of intervertebral disc (IVD and the incidence of Low Back Pain (LBP. Columbini evaluated the size of IVD anthropometricaly but how this measurement correlates with radiologic measurements of IVD square size is steel unknown.Objective. The aim of the study was to search for non-invasive method and cheap and fast evaluation of IVD size with the modification of Columbini’s antropometric formula.Materials and methods. The measurements (anthropometrics, X-ray, CT with range of interest measurement [ROI] were done on 40 bus-drivers. The realibility test was done on 65 bus-drivers.Results. CT measurement of the size of the intervertebral disc was done using ROI (Range of Interest. Using the statistical analysis based on linear regression, correlation, curve fitting and realibility the author made the modification of Columbini’s formula. The incidence of Low Back Pain was statistically significantly higher in people with smaller IVD, particularly in men.Conclusions. With the Columbini’s method of anthropometric measurement of the size of IVD modified by Turk it is possible to make the right measurement prognosis in 89% of cases. Consequently, there is no need to use invasive and costly diagnostic radiologic methods.

  12. Oscillations of disks

    CERN Document Server

    Kato, Shoji

    2016-01-01

    This book presents the current state of research on disk oscillation theory, focusing on relativistic disks and tidally deformed disks. Since the launch of the Rossi X-ray Timing Explorer (RXTE) in 1996, many high-frequency quasiperiodic oscillations (HFQPOs) have been observed in X-ray binaries. Subsequently, similar quasi-periodic oscillations have been found in such relativistic objects as microquasars, ultra-luminous X-ray sources, and galactic nuclei. One of the most promising explanations of their origin is based on oscillations in relativistic disks, and a new field called discoseismology is currently developing. After reviewing observational aspects, the book presents the basic characteristics of disk oscillations, especially focusing on those in relativistic disks. Relativistic disks are essentially different from Newtonian disks in terms of several basic characteristics of their disk oscillations, including the radial distributions of epicyclic frequencies. In order to understand the basic processes...

  13. Senescent intervertebral disc cells exhibit perturbed matrix homeostasis phenotype.

    Science.gov (United States)

    Ngo, Kevin; Patil, Prashanti; McGowan, Sara J; Niedernhofer, Laura J; Robbins, Paul D; Kang, James; Sowa, Gwendolyn; Vo, Nam

    2017-09-01

    Aging greatly increases the risk for intervertebral disc degeneration (IDD) as a result of proteoglycan loss due to reduced synthesis and enhanced degradation of the disc matrix proteoglycan (PG). How disc matrix PG homeostasis becomes perturbed with age is not known. The goal of this study is to determine whether cellular senescence is a source of this perturbation. We demonstrated that disc cellular senescence is dramatically increased in the DNA repair-deficient Ercc1(-/Δ) mouse model of human progeria. In these accelerated aging mice, increased disc cellular senescence is closely associated with the rapid loss of disc PG. We also directly examine PG homeostasis in oxidative damage-induced senescent human cells using an in vitro cell culture model system. Senescence of human disc cells treated with hydrogen peroxide was confirmed by growth arrest, senescence-associated β-galactosidase activity, γH2AX foci, and acquisition of senescence-associated secretory phenotype. Senescent human disc cells also exhibited perturbed matrix PG homeostasis as evidenced by their decreased capacity to synthesize new matrix PG and enhanced degradation of aggrecan, a major matrix PG. of the disc. Our in vivo and in vitro findings altogether suggest that disc cellular senescence is an important driver of PG matrix homeostatic perturbation and PG loss. Published by Elsevier B.V.

  14. Genetic and functional studies of the intervertebral disc: a novel murine intervertebral disc model.

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    Dominic W Pelle

    Full Text Available Intervertebral disc (IVD homeostasis is mediated through a combination of micro-environmental and biomechanical factors, all of which are subject to genetic influences. The aim of this study is to develop and characterize a genetically tractable, ex vivo organ culture model that can be used to further elucidate mechanisms of intervertebral disc disease. Specifically, we demonstrate that IVD disc explants (1 maintain their native phenotype in prolonged culture, (2 are responsive to exogenous stimuli, and (3 that relevant homeostatic regulatory mechanisms can be modulated through ex-vivo genetic recombination. We present a novel technique for isolation of murine IVD explants with demonstration of explant viability (CMFDA/propidium iodide staining, disc anatomy (H&E, maintenance of extracellular matrix (ECM (Alcian Blue staining, and native expression profile (qRT-PCR as well as ex vivo genetic recombination (mT/mG reporter mice; AdCre following 14 days of culture in DMEM media containing 10% fetal bovine serum, 1% L-glutamine, and 1% penicillin/streptomycin. IVD explants maintained their micro-anatomic integrity, ECM proteoglycan content, viability, and gene expression profile consistent with a homeostatic drive in culture. Treatment of genetically engineered explants with cre-expressing adenovirus efficaciously induced ex vivo genetic recombination in a variety of genetically engineered mouse models. Exogenous administration of IL-1ß and TGF-ß3 resulted in predicted catabolic and anabolic responses, respectively. Genetic recombination of TGFBR1fl/fl explants resulted in constitutively active TGF-ß signaling that matched that of exogenously administered TGF-ß3. Our results illustrate the utility of the murine intervertebral disc explant to investigate mechanisms of intervertebral disc degeneration.

  15. Genetic and Functional Studies of the Intervertebral Disc: A Novel Murine Intervertebral Disc Model

    Science.gov (United States)

    Pelle, Dominic W.; Peacock, Jacqueline D.; Schmidt, Courtney L.; Kampfschulte, Kevin; Scholten, Donald J.; Russo, Scott S.; Easton, Kenneth J.; Steensma, Matthew R.

    2014-01-01

    Intervertebral disc (IVD) homeostasis is mediated through a combination of micro-environmental and biomechanical factors, all of which are subject to genetic influences. The aim of this study is to develop and characterize a genetically tractable, ex vivo organ culture model that can be used to further elucidate mechanisms of intervertebral disc disease. Specifically, we demonstrate that IVD disc explants (1) maintain their native phenotype in prolonged culture, (2) are responsive to exogenous stimuli, and (3) that relevant homeostatic regulatory mechanisms can be modulated through ex-vivo genetic recombination. We present a novel technique for isolation of murine IVD explants with demonstration of explant viability (CMFDA/propidium iodide staining), disc anatomy (H&E), maintenance of extracellular matrix (ECM) (Alcian Blue staining), and native expression profile (qRT-PCR) as well as ex vivo genetic recombination (mT/mG reporter mice; AdCre) following 14 days of culture in DMEM media containing 10% fetal bovine serum, 1% L-glutamine, and 1% penicillin/streptomycin. IVD explants maintained their micro-anatomic integrity, ECM proteoglycan content, viability, and gene expression profile consistent with a homeostatic drive in culture. Treatment of genetically engineered explants with cre-expressing adenovirus efficaciously induced ex vivo genetic recombination in a variety of genetically engineered mouse models. Exogenous administration of IL-1ß and TGF-ß3 resulted in predicted catabolic and anabolic responses, respectively. Genetic recombination of TGFBR1fl/fl explants resulted in constitutively active TGF-ß signaling that matched that of exogenously administered TGF-ß3. Our results illustrate the utility of the murine intervertebral disc explant to investigate mechanisms of intervertebral disc degeneration. PMID:25474689

  16. New method for the speciation of ruthenium-based chemotherapeutics in human serum by conjoint liquid chromatography on affinity and anion-exchange monolithic disks.

    Science.gov (United States)

    Martinčič, Anže; Milačič, Radmila; Vidmar, Janja; Turel, Iztok; Keppler, Bernhard K; Sčančar, Janez

    2014-12-05

    An important step in pharmacological characterisation of a candidate drug is the study of the drugs interactions with serum proteins. In the present work, conjoint liquid chromatography (CLC) was used for separation of ruthenium (Ru)-based drug candidates in human serum. CIM Protein G and CIM DEAE disks were assembled together in a single housing forming a CLC monolithic column. By applying isocratic elution with Tris-HCl-NaHCO3 buffer (pH 7.4) in the first min, followed by gradient elution with 1 mol L(-1) NH4Cl (pH 7.4) in the next 9 min, immunoglobulins (IgG) were retained by the Protein G disk enabling subsequent separation of unbound Ru species from Ru species bound to human serum transferrin (Tf) and albumin (HSA) on the CIM DEAE disk. Finally, elution with acetic acid (AcOH) in the next 3 min allowed separation of Ru species associated with IgG. Protein elution was followed on-line with UV detection at 278nm, while the separated Ru species were quantified by post-column isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS). The instrumental set-up enabled fast two-dimensional separation by affinity and ion-exchange modes to be carried out in a single chromatographic run. Two Ru-based chemotherapeutics: a newly synthesised compound chlorido(η6-p-cymene)(nalidixicato-κ2O,O)Ru(II) (1) and (H2im)[trans-Ru(III)Cl4(Him)2] (2; KP418), which is currently undergoing preclinical studies, were investigated. The CLC procedure applied is sensitive with low limit of detection (LOD) (0.027 μg Ru mL(-1) for (1)) and good method repeatability (RSD±3.5%). The experimental data revealed that it enables investigation of the kinetics of interaction of positively charged and neutral complexes of metallodrugs with serum proteins as well as the distribution of metallodrug species in human serum. However, negatively charged metallic complexes co-eluted with Tf and HSA and thus hindered their speciation analysis. An example of successful application of the

  17. PDGF-BB inhibits intervertebral disc cell apoptosis in vitro.

    Science.gov (United States)

    Presciutti, Steven M; Paglia, David N; Karukonda, Teja; Soung, Do Yu; Guzzo, Rosa; Drissi, Hicham; Moss, Isaac L

    2014-09-01

    Degeneration of the intervertebral disc (IVD) results in deterioration of the spinal motion segment and can lead to debilitating back pain. Given the established mitotic and anti-apoptotic effects of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) in a variety of cell types we postulated that rhPDGF-BB might delay disc cell degeneration through inhibition of apoptosis. To address this hypothesis, we treated human IVD cells isolated from five independent patients with rhPDGF-BB in monolayer and 3D pellet cultures. The anti-apoptotic potential, cell proliferative capacity, morphology/pellet differentiation, and gene expression of PDGF-treated IVD cells were evaluated via flow cytometry/immunohistochemistry, MTT assays, histology, and quantitative RT-PCR, respectively. We found that rhPDGF-BB treatment significantly inhibited cell apoptosis, increased cell proliferation and matrix production, and maintained mRNA expression of critical extracellular matrix genes. This study suggests two possible mechanisms for the anti-degenerative effects of rhPDGF-BB on human IVD cells. First, PDGF treatment strongly inhibited IVD cell apoptosis in 3D cultures. Second, rhPDGF-BB acts as an anabolic agent, promoting maintenance of IVD cell phenotype in 3D culture, based on the molecular and protein expression analysis. We speculate that rhPDGF-BB may be used as a biologic treatment to target early degenerative IVD disease in the future. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  18. Axial T2* mapping in intervertebral discs: a new technique for assessment of intervertebral disc degeneration

    Energy Technology Data Exchange (ETDEWEB)

    Hoppe, Sven; Quirbach, Sebastian; Krause, Fabian G.; Benneker, Lorin M. [Inselspital, Berne University Hospital, Department of Orthopaedic Surgery, Berne (Switzerland); Mamisch, Tallal C. [Inselspital, Berne University Hospital, Department of Radiology, Berne (Switzerland); Werlen, Stefan [Clinic Sonnenhof, Department of Radiology, Berne (Switzerland)

    2012-09-15

    To demonstrate the potential benefits of biochemical axial T2* mapping of intervertebral discs (IVDs) regarding the detection and grading of early stages of degenerative disc disease using 1.5-Tesla magnetic resonance imaging (MRI) in a clinical setting. Ninety-three patients suffering from lumbar spine problems were examined using standard MRI protocols including an axial T2* mapping protocol. All discs were classified morphologically and grouped as ''healthy'' or ''abnormal''. Differences between groups were analysed regarding to the specific T2* pattern at different regions of interest (ROIs). Healthy intervertebral discs revealed a distinct cross-sectional T2* value profile: T2* values were significantly lower in the annulus fibrosus compared with the nucleus pulposus (P = 0.01). In abnormal IVDs, T2* values were significantly lower, especially towards the centre of the disc representing the expected decreased water content of the nucleus (P = 0.01). In herniated discs, ROIs within the nucleus pulposus and ROIs covering the annulus fibrosus showed decreased T2* values. Axial T2* mapping is effective to detect early stages of degenerative disc disease. There is a potential benefit of axial T2* mapping as a diagnostic tool, allowing the quantitative assessment of intervertebral disc degeneration. circle Axial T2* mapping effective in detecting early degenerative disc disease. (orig.)

  19. Disk Storage Server

    CERN Multimedia

    This model was a disk storage server used in the Data Centre up until 2012. Each tray contains a hard disk drive (see the 5TB hard disk drive on the main disk display section - this actually fits into one of the trays). There are 16 trays in all per server. There are hundreds of these servers mounted on racks in the Data Centre, as can be seen.

  20. Biomechanical analysis of the camelid cervical intervertebral disc

    Directory of Open Access Journals (Sweden)

    Dean K. Stolworthy

    2015-01-01

    Full Text Available Chronic low back pain (LBP is a prevalent global problem, which is often correlated with degenerative disc disease. The development and use of good, relevant animal models of the spine may improve treatment options for this condition. While no animal model is capable of reproducing the exact biology, anatomy, and biomechanics of the human spine, the quality of a particular animal model increases with the number of shared characteristics that are relevant to the human condition. The purpose of this study was to investigate the camelid (specifically, alpaca and llama cervical spine as a model of the human lumbar spine. Cervical spines were obtained from four alpacas and four llamas and individual segments were used for segmental flexibility/biomechanics and/or morphology/anatomy studies. Qualitative and quantitative data were compared for the alpaca and llama cervical spines, and human lumbar specimens in addition to other published large animal data. Results indicate that a camelid cervical intervertebral disc (IVD closely approximates the human lumbar disc with regard to size, spinal posture, and biomechanical flexibility. Specifically, compared with the human lumbar disc, the alpaca and llama cervical disc size are approximately 62%, 83%, and 75% with regard to area, depth, and width, respectively, and the disc flexibility is approximately 133%, 173%, and 254%, with regard to range of motion (ROM in axial-rotation, flexion-extension, and lateral-bending, respectively. These results, combined with the clinical report of disc degeneration in the llama lower cervical spine, suggest that the camelid cervical spine is potentially well suited for use as an animal model in biomechanical studies of the human lumbar spine.

  1. Spontaneous Regression of a Cervical Disk Herniation

    Directory of Open Access Journals (Sweden)

    Emre Delen

    2014-03-01

    Full Text Available A 54 years old female patient was admitted to our outpatient clinic with a two months history of muscle spasms of her neck and pain radiating to the left upper extremity. Magnetic resonance imaging had shown a large left-sided paracentral disk herniation at the C6-C7 disk space (Figure 1. Neurological examination showed no obvious neurological deficit. She received conservative treatment including bed rest, rehabilitation, and analgesic drugs. After 13 months, requested by the patient, a second magnetic resonance imaging study showed resolution of the disc herniation.(Figure 2 Although the literature contains several reports about spontaneous regression of herniated lumbar disc without surgical intervention, that of phenomenon reported for herniated cervical level is rare, and such reports are few[1]. In conclusion, herniated intervertebral disc have the potential to spontaneously regress independently from the spine level. With further studies, determining the predictive signs for prognostic evaluation for spontaneous regression which would yield to conservative treatment would be beneficial.

  2. Angiogenesis in the degeneration of the lumbar intervertebral disc

    Science.gov (United States)

    David, Gh; Iencean, SM; Mohan, A

    2010-01-01

    The goal of the study is to show the histological and biochemical changes that indicate the angiogenesis of the intervertebral disc in lumbar intervertebral disc hernia and the existence of epidemiological correlations between these changes and the risk factors of lumbar intervertebral disc hernia, as well as the patient's quality of life (QOL). We have studied 50 patients aged between 18 and 73 years old, who have undergone lumbar intervertebral disc hernia surgery, making fibroblast growth factor and vascular endothelial growth factor level measurements, as elements in the process of appreciating the disc angiogenesis. Also, pre–surgery and post–surgery QOL has been measured, as well as the intensity of the pain syndrome. We have identified factors capable of stimulating vascular endothelial growth (VEGF, FGF–2) for the examined disc material, but histological examination did not show angiogenesis. The process of angiogenesis at the degenerated intervertebral disc level affects the patient's quality of life both pre and postoperatively, and may be a predictive factor for the post–operative results. Patients can prevent the appearance of angiogenesis type degenerative processes of the intervertebral disc by avoiding angiogenesis correlated factors (weight control, physical effort, and smoking). PMID:20968201

  3. HNC IN PROTOPLANETARY DISKS

    Energy Technology Data Exchange (ETDEWEB)

    Graninger, Dawn; Öberg, Karin I.; Qi, Chunhua [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Kastner, Joel, E-mail: dgraninger@cfa.harvard.edu [Center for Imaging Science, School of Physics and Astronomy, and Laboratory for Multiwavelength Astrophysics, Rochester Institute of Technology, 54 Lomb Memorial Drive, Rochester, NY 14623 (United States)

    2015-07-01

    The distributions and abundances of small organics in protoplanetary disks are potentially powerful probes of disk physics and chemistry. HNC is a common probe of dense interstellar regions and the target of this study. We use the Submillimeter Array (SMA) to observe HNC 3–2 toward the protoplanetary disks around the T Tauri star TW Hya and the Herbig Ae star HD 163296. HNC is detected toward both disks, constituting the first spatially resolved observations of HNC in disks. We also present SMA observations of HCN 3–2 and IRAM 30 m observations of HCN and HNC 1–0 toward HD 163296. The disk-averaged HNC/HCN emission ratio is 0.1–0.2 toward both disks. Toward TW Hya, the HNC emission is confined to a ring. The varying HNC abundance in the TW Hya disk demonstrates that HNC chemistry is strongly linked to the disk physical structure. In particular, the inner rim of the HNC ring can be explained by efficient destruction of HNC at elevated temperatures, similar to what is observed in the ISM. However, to realize the full potential of HNC as a disk tracer requires a combination of high SNR spatially resolved observations of HNC and HCN and disk-specific HNC chemical modeling.

  4. Determination of selected persistent organochlorine pollutants in human milk using solid phase disk extraction and narrow bore capillary GC-MS

    Energy Technology Data Exchange (ETDEWEB)

    Covaci, A.; Schepens, P. [Antwerp Univ., Wilrijk (Belgium). Toxicological Center; Hura, C. [Royal Inst. of Public Administration (RIPA), Reading (United Kingdom). Health Operational Research Unit

    2001-08-01

    A simple and rapid procedure based on solid phase disk extraction (SPDE), adsorption chromatography on acidified silica gel and GC-MS analysis was developed for the determination of 8 organochlorine pesticides and 19 PCB congeners in human milk. By using the SPDE procedure, a high throughput and parallel sample processing could be achieved. Method variables were optimized on whole cow's milk (3.5% fat) fortified at levels close to concentrations found in human milk. Recoveries of target analytes were acceptable and ranged from 69 to 102% and 86 to 120% for whole and skimmed milk, respectively. By the use of two stage clean-up and narrow bore capillary columns, detection limits as low as 20 pg mL{sup -1} could be obtained. The method was used for the determination of organochlorine pollutants in human milk from 19 individuals from Romania. The concentrations of PCBs were low, whereas those of organochlorine pesticides were higher than the values reported from other European countries. (orig.)

  5. The occurrence and regional distribution of DR4 on herniated disc cells: a potential apoptosis pathway in lumbar intervertebral disc.

    Science.gov (United States)

    Zhang, Liang; Niu, Tao; Yang, Shang-You; Lu, Zhenhua; Chen, Bohua

    2008-02-15

    Intervertebral discs surgically obtained from 60 herniated patients and 5 normal individuals were examined to correlate the regional distribution of DR4-receptor and apoptosis. To explore the role of a tumor necrosis factor superfamily member DR4 and the TRAIL/DR4 mediated apoptosis in the human lumbar intervertebral disc. The pathogenesis of lumbar degenerative intervertebral discs remains not completely understood. In herniated lumbar disc tissues, increased apoptosis and higher expression of Fas/Fas ligand and caspase-3 have been reported, suggesting a pivotal role of apoptotic mechanisms in intervertebral disc degeneration. However, it is not clear that apoptosis mediators such as TRAIL and Death Receptor 4 (DR4), which often represent different apoptosis signal pathways, contribute to the apoptosis process during the development of the degenerated intervertebral discs. Apoptosis was determined by poly(ADP-ribose) polymerase (PARP) p85 immunohistochemistry. Expression of DR4 was revealed by immunohistochemistry analysis. Statistical difference among groups was analyzed using one-way ANOVA with LSD post hoc multiple comparisons and the bivariate correlations. Apoptotic cells were detected in the nucleus pulposus and anulus fibrosus of all samples. However, the number of apoptotic cells was significantly higher in the nucleus compared with the anulus. Further, there were significantly more apoptotic cells in the herniated discs compared with the normal discs. Within herniated discs, a remarkably higher percentage of positive staining cells were detected in the uncontained discs than the contained ones. Strong expression of DR4 was detected in all samples of degenerative herniated discs, whereasmuch weaker expression was sporadically identified in normal discs. In addition, the prevalence of apoptosis positively correlated with the severity of disc degeneration. The concomitant increase of DR4 expression in the regions of heavy apoptotic cell aggregation suggests

  6. Bovine explant model of degeneration of the intervertebral disc

    Directory of Open Access Journals (Sweden)

    Sivan Sarit

    2008-02-01

    Full Text Available Abstract Background Many new treatments for degeneration of the intervertebral disc are being developed which can be delivered through a needle. These require testing in model systems before being used in human patients. Unfortunately, because of differences in anatomy, there are no ideal animal models of disc degeneration. Bovine explant model systems have many advantages but it is not possible to inject any significant volume into an intact disc. Therefore we have attempted to mimic disc degeneration in an explant bovine model via enzymatic digestion. Methods Bovine coccygeal discs were incubated with different concentrations of the proteolytic enzymes, trypsin and papain, and maintained in culture for up to 3 weeks. A radio-opaque solution was injected to visualise cavities generated. Degenerative features were monitored histologically and biochemically (water and glycosaminoglycan content, via dimethylmethylene blue. Results and Conclusion The central region of both papain and trypsin treated discs was macro- and microscopically fragmented, with severe loss of metachromasia. The integrity of the surrounding tissue was mostly in tact with cells in the outer annulus appearing viable. Biochemical analysis demonstrated greatly reduced glycosaminoglycan content in these compared to untreated discs. We have shown that bovine coccygeal discs, treated with proteolytic enzymes can provide a useful in vitro model system for developing and testing potential new treatments of disc degeneration, such as injectable implants or biological therapies.

  7. Exploring Disks Around Planets

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    Giant planets are thought to form in circumstellar disks surrounding young stars, but material may also accrete into a smaller disk around the planet. Weve never detected one of these circumplanetary disks before but thanks to new simulations, we now have a better idea of what to look for.Image from previous work simulating a Jupiter-mass planet forming inside a circumstellar disk. The planet has its own circumplanetary disk of accreted material. [Frdric Masset]Elusive DisksIn the formation of giant planets, we think the final phase consists of accretion onto the planet from a disk that surrounds it. This circumplanetary disk is important to understand, since it both regulates the late gas accretion and forms the birthplace of future satellites of the planet.Weve yet to detect a circumplanetary disk thus far, because the resolution needed to spot one has been out of reach. Now, however, were entering an era where the disk and its kinematics may be observable with high-powered telescopes (like the Atacama Large Millimeter Array).To prepare for such observations, we need models that predict the basic characteristics of these disks like the mass, temperature, and kinematic properties. Now a researcher at the ETH Zrich Institute for Astronomy in Switzerland, Judit Szulgyi, has worked toward this goal.Simulating CoolingSzulgyi performs a series of 3D global radiative hydrodynamic simulations of 1, 3, 5, and 10 Jupiter-mass (MJ) giant planets and their surrounding circumplanetary disks, embedded within the larger circumstellar disk around the central star.Density (left column), temperature (center), and normalized angular momentum (right) for a 1 MJ planet over temperatures cooling from 10,000 K (top) to 1,000 K (bottom). At high temperatures, a spherical circumplanetary envelope surrounds the planet, but as the planet cools, the envelope transitions around 64,000 K to a flattened disk. [Szulgyi 2017]This work explores the effects of different planet temperatures and

  8. ISSLS Prize Winner: Dynamic Loading-Induced Convective Transport Enhances Intervertebral Disc Nutrition

    NARCIS (Netherlands)

    Gullbrand, S.E.; Peterson, J.; Ahlborn, J.; Mastropolo, R.; Fricker, A.; Roberts, T.T.; Abousayed, M.; Lawrence, J.P.; Glennon, J.C.; Ledet, E.H.

    2015-01-01

    STUDY DESIGN: Experimental animal study of convective transport in the intervertebral disc. OBJECTIVE: To quantify the effects of mechanical loading rate on net transport into the healthy and degenerative intervertebral disc in vivo. SUMMARY OF BACKGROUND DATA: Intervertebral disc degeneration is

  9. Isolated unilateral disk edema

    Directory of Open Access Journals (Sweden)

    Varner P

    2011-07-01

    Full Text Available Paul VarnerJohn J Pershing VAMC, Poplar Bluff, MO, USAAbstract: Isolated unilateral disk edema is a familiar clinical presentation with myriad associations. Related, non-consensus terminology is a barrier to understanding a common pathogenesis. Mechanisms for the development of disk edema are reviewed, and a new framework for clinical differentiation of medical associations is presented.Keywords: disk edema, axoplasmic flow, clinical multiplier, optic neuritis, ischemic optic neuropathy, papilledema

  10. Effect of a novel compressible artificial disk on biomechanical performance of cervical spine: A finite element study

    Directory of Open Access Journals (Sweden)

    Jou-Wen Chen

    2015-08-01

    Full Text Available Spinal interbody fusion is the most common surgery for treatment of disk degeneration, but the increased stress on adjacent level has been noted. Disk replacement has become an alternative strategy for dealing with problem of disk degeneration. Compressibility of an intact intervertebral disk is contributive to protect spinal structure, but certain mechanism has seldom been preserved in most of the commercial products of ball-and-socket-styled artificial disks. A novel compressible artificial disk design for cervical spine has been developed and compared the biomechanical behaviors with intact and incompressible models by finite element method. Physiological loadings have been applied for evaluating the biomechanical performances in different implant designs. Compressible mechanism represented a similar kinematic behavior to intact cervical spine model. Greater mobility and larger facet joint contact force were observed in incompressible disk model. Biomechanical performances of cervical artificial disk with compressible mechanism may be better reproduced to those of intact cervical spine under physiological loadings. With adequate assigned structural stiffness of the compressible mechanism in the artificial disk, the concept is worth considering for further cervical artificial disk designs.

  11. Total disc replacement using a tissue-engineered intervertebral disc in vivo: new animal model and initial results

    OpenAIRE

    Gebhard, Harry; Bowles, Robby; Dyke, Jonathan; Saleh, Tatianna; Doty, Stephen; Bonassar, Lawrence; Härtl, Roger; H?rtl, Roger

    2010-01-01

    Study type: ?Basic science Introduction: ?Chronic back pain due to degenerative disc disease (DDD) is among the most important medical conditions causing morbidity and significant health care costs. Surgical treatment options include disc replacement or fusion surgery, but are associated with significant short- and long-term risks.1 Biological tissue-engineering of human intervertebral discs (IVD) could offer an important alternative.2 Recent in vitro data from our group have shown successful...

  12. Towards the Scale up of Tissue Engineered Intervertebral Discs for Clinical Application.

    Science.gov (United States)

    Gullbrand, Sarah E; Kim, Dong Hwa; Bonnevie, Edward; Ashinsky, Beth G; Smith, Lachlan J; Elliott, Dawn M; Mauck, Robert L; Smith, Harvey E

    2018-02-07

    Replacement of the intervertebral disc with a viable, tissue-engineered construct that mimics native tissue structure and function is an attractive alternative to fusion or mechanical arthroplasty for the treatment of disc pathology. While a number of engineered discs have been developed, the average size of these constructs remains a fraction of the size of human intervertebral discs. In this study, we fabricated medium (3 mm height x 10 mm diameter) and large (6 mm height x 20 mm diameter) sized disc-like angle ply structures (DAPS), encompassing size scales from the rabbit lumbar spine to the human cervical spine. Maturation of these engineered discs was evaluated over 15 weeks in culture by quantifying cell viability and metabolic activity, construct biochemical content, MRI T2 values, and mechanical properties. To assess the performance of the DAPS in the in vivo space, pre-cultured DAPS were implanted subcutaneously in athymic rats for 5 weeks. Our findings show that both sized DAPS matured functionally and compositionally during in vitro culture, as evidenced by increases in mechanical properties and biochemical content over time, yet large DAPS under-performed compared to medium DAPS. Subcutaneous implantation resulted in reductions in NP cell viability and GAG content at both size scales, with little effect on AF biochemistry or metabolic activity. These findings demonstrate that engineered discs at large size scales will mature during in vitro culture, however, future work will need to address the challenges of reduced cell viability and heterogeneous matrix distribution throughout the construct. Statement of Significance This work establishes, for the first time, tissue-engineered intervertebral discs for total disc replacement at large, clinically relevant length scales. Clinical translation of tissue-engineered discs will offer an alternative to mechanical disc arthroplasty and fusion procedures, and may contribute to a paradigm shift in the clinical

  13. A role for TNFα in intervertebral disc degeneration: A non-recoverable catabolic shift

    Energy Technology Data Exchange (ETDEWEB)

    Purmessur, D.; Walter, B.A. [Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Roughley, P.J. [Shriners Hospital for Children, Montreal, QC (Canada); Laudier, D.M.; Hecht, A.C. [Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States); Iatridis, James, E-mail: james.iatridis@mssm.edu [Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 (United States)

    2013-03-29

    Highlights: ► TNFα induced catabolic changes similar to human intervertebral disc degeneration. ► The metabolic shift induced by TNFα was sustained following removal. ► TNFα induced changes suggestive of cell senescence without affecting cell viability. ► Interventions are required to stimulate anabolism and increase cell proliferation. -- Abstract: This study examines the effect of TNFα on whole bovine intervertebral discs in organ culture and its association with changes characteristic of intervertebral disc degeneration (IDD) in order to inform future treatments to mitigate the chronic inflammatory state commonly found with painful IDD. Pro-inflammatory cytokines such as TNFα contribute to disc pathology and are implicated in the catabolic phenotype associated with painful IDD. Whole bovine discs were cultured to examine cellular (anabolic/catabolic gene expression, cell viability and senescence using β-galactosidase) and structural (histology and aggrecan degradation) changes in response to TNFα treatment. Control or TNFα cultures were assessed at 7 and 21 days; the 21 day group also included a recovery group with 7 days TNFα followed by 14 days in basal media. TNFα induced catabolic and anti-anabolic shifts in the nucleus pulposus (NP) and annulus fibrosus (AF) at 7 days and this persisted until 21 days however cell viability was not affected. Data indicates that TNFα increased aggrecan degradation products and suggests increased β-galactosidase staining at 21 days without any recovery. TNFα treatment of whole bovine discs for 7 days induced changes similar to the degeneration processes that occur in human IDD: aggrecan degradation, increased catabolism, pro-inflammatory cytokines and nerve growth factor expression. TNFα significantly reduced anabolism in cultured IVDs and a possible mechanism may be associated with cell senescence. Results therefore suggest that successful treatments must promote anabolism and cell proliferation in

  14. disk historie

    DEFF Research Database (Denmark)

    Feldt, Jakob Egholm

    2012-01-01

    Review essay om nye værker indenfor jødisk kulturhistorie. Diskussion af værker af Jay Geller, Boaz Neumann og Daniel Greene......Review essay om nye værker indenfor jødisk kulturhistorie. Diskussion af værker af Jay Geller, Boaz Neumann og Daniel Greene...

  15. Inflammatory Processes Associated with Canine Intervertebral Disc Herniation

    Directory of Open Access Journals (Sweden)

    Marie Monchaux

    2017-12-01

    Full Text Available Intervertebral disc herniation (IVDH is an important pathology in humans and also in dogs. While the molecular disease mechanisms are well investigated in humans, little is known about the inflammatory mediators in naturally occurring canine IVDH. The objective of this study was to investigate whether the involved proinflammatory cytokines in human IVDH are also key cytokines in canine IVDH and thus to elucidate the suitability of the dog as a model for human trials. 59 samples from 25 dogs with surgically confirmed thoracolumbar IVDH were collected and classified in three subgroups: herniated (H, affected non-herniated (NH disc, and adjacent non-affected (NA disc. Discs from 11 healthy dogs acted as controls (C. Samples were analyzed for IL-1, IL-6, IL-8, and TNF-α expression (qPCR/ELISA as well as cell infiltration and activation of the MAP kinase pathways (immunohistochemistry. Gene and protein expression of all key cytokines could be detected in IVDH affected dogs. Canine IVDH was significantly associated with a higher gene expression of IL-6 (H > C, NH > C and TNF-α (H > C, NH > C, NA > C and a significant down-regulation of IL-1β (H < C. Dogs with spontaneous pain had significantly higher IL-6 mRNA compared to those with pain arising only upon palpation. An inter-donor comparison (H and HN relative to NA revealed a significant increase of IL-6 gene expression (H > NA, NH > NA. IL-8 (H > C, NA > C and TNF-α (NH > C protein levels were significantly increased in diseased dogs while inversely, IL-6 protein levels were significantly higher in patients with better clinical outcome. Aside from resident IVD cells, mostly monocytes and macrophages were found in extruded material, with concomitant activation of extracellular signal-regulated kinase p38 in the majority of samples. Dogs with spontaneous IVDH might provide a useful model for human disc diseases. Although the expression of key cytokines

  16. Classification of age-related changes in lumbar intervertebral discs: 2002 Volvo Award in basic science.

    Science.gov (United States)

    Boos, Norbert; Weissbach, Sabine; Rohrbach, Helmut; Weiler, Christoph; Spratt, Kevin F; Nerlich, Andreas G

    2002-12-01

    A histologic study on age-related changes of the human lumbar intervertebral disc was conducted. To investigate comprehensively age-related temporospatial histologic changes in human lumbar intervertebral disc, and to develop a practicable and reliable classification system for age-related histologic disc alteration. No comprehensive microscopic analysis of age-related disc changes is available. There is no conceptual morphologic framework for classifying age-related disc changes as a reference basis for more sophisticated molecular biologic analyses of the causative factors of disc aging or premature aging (degeneration). A total of 180 complete sagittal lumbar motion segment slices obtained from 44 deceased individuals (fetal to 88 years of age) were analyzed with regard to 11 histologic variables for the intervertebral disc and endplate, respectively. In addition, 30 surgical specimens (3 regions each) were investigated with regard to five histologic variables. Based on the semiquantitative analyses of 20,250 histologic variable assessments, a classification system was developed and tested in terms of validity, practicability, and reliability. The classification system was applied to cadaveric and surgical disc specimens not included in the development of the classification system, and the scores were assessed by two additional independent raters. A semiquantitative analyses provided clear histologic evidence for the detrimental effect of a diminished blood supply on the endplate, resulting in the tissue breakdown beginning in the nucleus pulposus and starting in the second life decade. Significant temporospatial variations in the presence and abundance of histologic disc alterations were observed across levels, regions, macroscopic degeneration grades, and age groups. A practicable classification system for age-related histologic disc alterations was developed, resulting in moderate to excellent reliability (kappa values, 0.49-0.98) depending on the histologic

  17. Sudden progression of lumbar disk protrusion during vertebral axial decompression traction therapy.

    Science.gov (United States)

    Deen, H Gordon; Rizzo, Thomas D; Fenton, Douglas S

    2003-12-01

    Vertebral axial decompression (VAX-D) is a form of spinal traction that is widely promoted as an effective and safe treatment of degenerated and herniated lumbar intervertebral disks. Information targeted at the general public emphasizes that the treatment is completely risk-free. We describe a patient with a large lumbar disk protrusion who experienced sudden, severe exacerbation of radicular pain during a VAX-D therapy session. Follow-up magnetic resonance imaging of the lumbar region showed marked enlargement of the disk protrusion, and urgent microdiskectomy was required. To our knowledge, this is the first reported complication of VAX-D therapy. This case shows that VAX-D therapy has the potential to cause sudden deterioration requiring urgent surgical intervention.

  18. A statistical model for intervertebral disc degeneration: determination of the optimal T2 cut-off values.

    Science.gov (United States)

    Nagy, S A; Juhasz, I; Komaromy, H; Pozsar, K; Zsigmond, I; Perlaki, G; Orsi, G; Schwarcz, A; Walter, N; Doczi, T; Bogner, P

    2014-12-01

    The aim of this study was to investigate the possibility of quantitative classification in intervertebral disc degeneration using spin-spin relaxation time (T2) cut-off values with regard to morphological classifications. Lumbar magnetic resonance (MR) imaging was performed on 21 subjects (a total of 104 lumbar disks). The T2 relaxation time was measured in the nucleus pulposus using a sagittal multi-echo spin-echo sequence. The morphological classification of disc degeneration was assessed independently by three experienced neuroradiologists according to the Pfirrmann and Schneiderman classifications. Receiver operating characteristic analysis was performed among grades to determine T2 cut-off values in each classification. Intra- and interobserver differences were calculated using kappa statistics. Moderate overall interobserver agreement was found between observers in both the Pfirrmann and Schneiderman classification schemes (kappa 0.46 and 0.51), while intraobserver reliability was substantial to almost perfect. The interobserver reliability was only fair in Pfirrmann grades III and IV (kappa 0.33 and 0.36), but the T2 cut-off values still indicated a significant difference between grades (pcut-off values seem to be a more reliable method to define the degree of disc degeneration, which may help staging intervertebral disc degeneration (IVDD) even if the interobserver reliability is low.

  19. FoxC2 Enhances BMP7-Mediated Anabolism in Nucleus Pulposus Cells of the Intervertebral Disc.

    Science.gov (United States)

    Wang, Zheng; Fu, Changfeng; Chen, Yong; Xu, Feng; Wang, Zhenyu; Qu, Zhigang; Liu, Yi

    2016-01-01

    Bone-morphogenetic protein-7 (BMP-7) is a growth factor that plays a major role in mediating anabolism and anti-catabolism of the intervertebral disc matrix and cell homeostasis. In osteoblasts, Forkhead box protein C2 (FoxC2) is a downstream target of BMPs and promotes cell proliferation and differentiation. However, the role FoxC2 may play in degenerative human intervertebral disc tissue and the relationship between FoxC2 and BMP-7 in nucleus pulposus (NP) cells remain to be elucidated. This study aims to investigate the presence and signaling mechanisms of FoxC2 in degenerative human intervertebral disc tissue and NP cells. Western blot and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) analyses were used to measure FoxC2 expression in the NP tissue and cells. Transfections were carried out to measure the effect of FoxC2 on BMP-7-mediated extracellular matrix upregulation. Adenoviral knock-down of Smad1 was performed to investigate the mechanism of BMP-7-induced FoxC2 expression. In degenerative NP tissue, FoxC2 was markedly upregulated and positively correlated with increased disc degeneration. Induction of NP cell proliferation was confirmed by using cell counting kit-8 assay, immunocytochemistry and real-time qRT-PCR for Ki67. FoxC2 led to decreased noggin expression and increased Smad1/5/8 phosphorylation. During combined treatment with BMP-7, FoxC2 greatly potentiated anabolism through synergistic mechanisms on ECM formation. Combination therapy using BMP-7 and FoxC2 may be beneficial to the treatment of intervertebral disc degeneration.

  20. Thick Disks of Lenticular Galaxies

    OpenAIRE

    Pohlen, M.; Balcells, M.; Luetticke, R.; Dettmar, R. -J.

    2004-01-01

    Thick disks are faint and extended stellar components found around several disk galaxies including our Milky Way. The Milky Way thick disk, the only one studied in detail, contains mostly old disk stars (~10 Gyr), so that thick disks are likely to trace the early stages of disk evolution. Previous detections of thick disk stellar light in external galaxies have been originally made for early-type, edge-on galaxies but detailed 2D thick/thin disk decompositions have been reported for only a sc...

  1. 21 CFR 888.3060 - Spinal intervertebral body fixation orthosis.

    Science.gov (United States)

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3060 Spinal intervertebral... each of a series of vertebral bodies. An eye-type screw is inserted in a hole in the center of each of the plates. A braided cable is threaded through each eye-type screw. The cable is tightened with a...

  2. Potential regenerative treatment strategies for intervertebral disc degeneration in dogs

    NARCIS (Netherlands)

    Bach, Frances C|info:eu-repo/dai/nl/369494954; Willems, Nicole; Penning, Louis C|info:eu-repo/dai/nl/110369181; Ito, Keita; Meij, Björn P|info:eu-repo/dai/nl/164045805; Tryfonidou, Marianna A|info:eu-repo/dai/nl/24306599X

    Pain due to spontaneous intervertebral disc (IVD) disease is common in dogs. In chondrodystrophic (CD) dogs, IVD disease typically develops in the cervical or thoracolumbar spine at about 3-7 years of age, whereas in non-chondrodystrophic (NCD) dogs, it usually develops in the caudal cervical or

  3. Molecular changes in the degenerated goat intervertebral disc

    NARCIS (Netherlands)

    Hoogendoorn, R.; Doulabi, B.Z.; Huang, C.L.; Wuisman, P.I.; Bank, R.A.; Helder, M.N.

    2008-01-01

    Study Design. Caprine lumbar intervertebral discs (IVD) were collected from previous studies and categorized as normal, mildly, or severely degenerated. The biochemical composition and the RNA profiles present in both the nucleus pulposus (NP) and the anulus fibrosus (AF) were analyzed. Objective.

  4. Delivery systems for the treatment of degenerated intervertebral discs

    NARCIS (Netherlands)

    Blanquer, Sebastien; Grijpma, Dirk W.; Poot, Andreas A.

    2015-01-01

    The intervertebral disc (IVD) is the most avascular and acellular tissue in the body and therefore prone to degeneration. During IVD degeneration, the balance between anabolic and catabolic processes in the disc is deregulated, amongst others leading to alteration of extracellular matrix production,

  5. Delivery systems for the treatment of degenerated intervertebral discs

    NARCIS (Netherlands)

    Blanquer, S. B. G.; Grijpma, D. W.; Poot, A. A.

    The intervertebral disc (ND) is the most avascular and acellular tissue in the body and therefore prone to degeneration. During IVD degeneration, the balance between anabolic and catabolic processes in the disc is deregulated, amongst others leading to alteration of extracellular matrix production,

  6. 1991 Volvo Award in basic sciences. Collagen types around the cells of the intervertebral disc and cartilage end plate: an immunolocalization study.

    Science.gov (United States)

    Roberts, S; Menage, J; Duance, V; Wotton, S; Ayad, S

    1991-09-01

    Several types of collagen are known to exist in the intervertebral disc in addition to the fibrillar collagens, Types I and II. Although they constitute only a small percentage of the total collagen content, these minor collagens may have important functions. This study was designed to investigate the presence of Types I, II, III, IV, VI, and IX collagens in the intervertebral disc and cartilage end plate by immunohistochemistry, thereby establishing their location within the tissues. Types III and VI collagen have a pericellular distribution in animal and human tissue. No staining for Type IX collagen was present in normal human disc, but in rat and bovine intervertebral disc, it was also located pericellularly. These results show that cells of the intervertebral disc and cartilage end plate sit in fibrous capsules, forming chondrons similar to those described in articular cartilage. In pathologic tissue the amount and distribution of the collagen types, and the organization of the pericellular capsule, differ from that seen in control material.

  7. Genetic Alterations in Intervertebral Disc Disease

    Directory of Open Access Journals (Sweden)

    Nikolay L. Martirosyan

    2016-11-01

    Full Text Available Background: Intervertebral disc degeneration (IVDD is considered a multifactorial disease. The last two decades of research strongly demonstrate that genetic factors contribute about 75% of the IVDD etiology. Recent total genome sequencing studies have shed light on the various single nucleotide polymorphisms (SNPs that are associated with IVDD.Aim: This review explores and presents updated information about the diversity of genetic factors in the inflammatory, degradative, homeostatic, and structural systems involved in the IVDD.Results: SNPs in the genes coding for structural proteins linked with IVDD or disc bulging include the Sp1 polymorphism of COL1A1, Trp3 polymorphism of COL9A3, several polymorphisms of COL11A1 and COL11A2, and a variable number tandem repeat polymorphism of ACAN. The rs4148941 SNP of CHST3 coding for an aggrecan sulfation enzyme is also associated with IVDD. The FokI, TaqI, and ApaI SNPs of the vitamin D receptor gene that is involved in chondrocyte functioning are also associated with IVDD. SNPs relevant to cytokine imbalance in IVDD include 889C/T of IL1a and 15T/A, as well as other SNPs (rs1800795, rs1800796, and rs1800797, of IL6, with effects limited to certain genders and populations. SNPs in collagenase genes include -1605G/D (guanine insertion/deletion of MMP1, -1306C/T of MMP2, -1562C/T and a 5-adenosine (5A variant (in the promotor region of MMP3, -1562C/T of MMP9, and -378T/C of MMP-14. SNPs in aggrecanase genes include 1877T/U of ADAMTS-4 and rs162509 of ADAMTS-5. Among the apoptosis-mediating genes, 1595T/C of the caspase 9 gene, 1525A/G and 1595T/C of the TRAIL gene, and 626C/G of the death receptor 4 gene (DR4 are SNPs associated with IVDD. Among the growth factors involved in disc homeostasis, the rs4871857 SNP of GDF5 was associated with IVDD. VEGF SNPs -2578C/A and -634G/C could foster neovascularization observed in IVDD.Conclusion: Improved understanding of the numerous genetic variants behind various

  8. Gas in Protoplanetary Disks

    Science.gov (United States)

    Roberge, Aki

    2008-01-01

    Gas makes up the bulk of the mass in a protoplanetary disk, but it is much more difficult to observe than the smaller dust component. The l ifetime of gas in a disk has far-reaching consequences. including lim iting the time available for giant planet formation and controlling t he migration of planetary bodies of all sizes, from Jupiters to meter-sized planetesimals. Here I will discuss what is known about the gas component of protoplanetary disks, highlighting recent results from i nfrared studies with the Spitzer Space Telescope. Exciting upcoming o pportunities for gas studies will also be discussed. In particular, the first large far-IR survey of gas tracers from young disks will be p erformed using the Herschel Space Observatory, as part of the "Gas in Protoplanetary Systems" (GASPS) Open Time Key Project.

  9. Disk Defect Data

    Data.gov (United States)

    National Aeronautics and Space Administration — How Data Was Acquired: The data presented is from a physical simulator that simulated engine disks. Sample Rates and Parameter Description: All parameters are...

  10. Verbatim Floppy Disk

    CERN Multimedia

    1976-01-01

    Introduced under the name "Verbatim", Latin for "literally", these disks that sized more than 5¼ inches have become almost universal on dedicated word processing systems and personal computers. This format was replaced more slowly by the 3½-inch format, introduced for the first time in 1982. Compared to today, these large format disks stored very little data. In reality, they could only contain a few pages of text.

  11. The Natural Polyphenol Epigallocatechin Gallate Protects Intervertebral Disc Cells from Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Olga Krupkova

    2016-01-01

    Full Text Available Oxidative stress-related phenotypic changes and a decline in the number of viable cells are crucial contributors to intervertebral disc degeneration. The polyphenol epigallocatechin 3-gallate (EGCG can interfere with painful disc degeneration by reducing inflammation, catabolism, and pain. In this study, we hypothesized that EGCG furthermore protects against senescence and/or cell death, induced by oxidative stress. Sublethal and lethal oxidative stress were induced in primary human intervertebral disc cells with H2O2 (total n=36. Under sublethal conditions, the effects of EGCG on p53-p21 activation, proliferative capacity, and accumulation of senescence-associated β-galactosidase were tested. Further, the effects of EGCG on mitochondria depolarization and cell viability were analyzed in lethal oxidative stress. The inhibitor LY249002 was applied to investigate the PI3K/Akt pathway. EGCG inhibited accumulation of senescence-associated β-galactosidase but did not affect the loss of proliferative capacity, suggesting that EGCG did not fully neutralize exogenous radicals. Furthermore, EGCG increased the survival of IVD cells in lethal oxidative stress via activation of prosurvival PI3K/Akt and protection of mitochondria. We demonstrated that EGCG not only inhibits inflammation but also can enhance the survival of disc cells in oxidative stress, which makes it a suitable candidate for the development of novel therapies targeting disc degeneration.

  12. Physiological effects of physical therapy interventions on lumbar intervertebral discs: A systematic review.

    Science.gov (United States)

    Mitchell, Ulrike H; Helgeson, Kevin; Mintken, Paul

    2017-09-01

    The use of physical therapy has been recommended in the treatment of low back pain based on primarily mechanical and neurophysiological effects. Recent studies have measured the physiological effects of physical therapy interventions, including manual therapy and traction, on the intervertebral discs (IVD), and these findings may have implications for the long-term management or even prevention of low back pain. The objective of this systematic review is to investigate the literature regarding possible physiological effects of physical therapy interventions on the intervertebral disc (IVD). Systematic Review. A literature search of published articles through December 2014 resulted in the retrieval of 8 clinical studies assessing the influence of physical therapy interventions on the physiology of the IVD. Three studies, including two using animal models, investigated the effects of 30-minute intermittent traction on disc height. One in vivo animal study and two studies using human subjects assessed changes of disc height associated with static traction. Three studies investigated the effects of lumbar spine manipulation and mobilization on changes in water diffusion within the IVD. All studies confirmed, either directly or indirectly, that their respective intervention influenced disc physiology primarily through water flow. Physical therapy interventions may have an effect on the physiology of the IVD, primarily through water diffusion and molecular transport, which are important for the health of the IVD.

  13. 2TB hard disk drive

    CERN Multimedia

    This particular object was used up until 2012 in the Data Centre. It slots into one of the Disk Server trays. Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes (link is external). They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product). They later became known as "hard disks" to distinguish them from "floppy disks (link is external)." Hard disks have a hard platter that holds the magnetic medium, as opposed to the flexible plastic film found in tapes and floppies.

  14. Running Exercise Alleviates Pain and Promotes Cell Proliferation in a Rat Model of Intervertebral Disc Degeneration

    Directory of Open Access Journals (Sweden)

    Shuo Luan

    2015-01-01

    Full Text Available Chronic low back pain accompanied by intervertebral disk degeneration is a common musculoskeletal disorder. Physical exercise, which is clinically recommended by international guidelines, has proven to be effective for degenerative disc disease (DDD patients. However, the mechanism underlying the analgesic effects of physical exercise on DDD remains largely unclear. The results of the present study showed that mechanical withdrawal thresholds of bilateral hindpaw were significantly decreased beginning on day three after intradiscal complete Freund’s adjuvant (CFA injection and daily running exercise remarkably reduced allodynia in the CFA exercise group beginning at day 28 compared to the spontaneous recovery group (controls. The hindpaw withdrawal thresholds of the exercise group returned nearly to baseline at the end of experiment, but severe pain persisted in the control group. Histological examinations performed on day 70 revealed that running exercise restored the degenerative discs and increased the cell densities of the annulus fibrosus (AF and nucleus pulposus (NP. Furthermore, immunofluorescence labeling revealed significantly higher numbers of 5-bromo-2-deoxyuridine (BrdU-positive cells in the exercise group on days 28, 42, 56 and 70, which indicated more rapid proliferation compared to the control at the corresponding time points. Taken together, these results suggest that running exercise might alleviate the mechanical allodynia induced by intradiscal CFA injection via disc repair and cell proliferation, which provides new evidence for future clinical use.

  15. Premixed direct injection disk

    Science.gov (United States)

    York, William David; Ziminsky, Willy Steve; Johnson, Thomas Edward; Lacy, Benjamin; Zuo, Baifang; Uhm, Jong Ho

    2013-04-23

    A fuel/air mixing disk for use in a fuel/air mixing combustor assembly is provided. The disk includes a first face, a second face, and at least one fuel plenum disposed therebetween. A plurality of fuel/air mixing tubes extend through the pre-mixing disk, each mixing tube including an outer tube wall extending axially along a tube axis and in fluid communication with the at least one fuel plenum. At least a portion of the plurality of fuel/air mixing tubes further includes at least one fuel injection hole have a fuel injection hole diameter extending through said outer tube wall, the fuel injection hole having an injection angle relative to the tube axis. The invention provides good fuel air mixing with low combustion generated NOx and low flow pressure loss translating to a high gas turbine efficiency, that is durable, and resistant to flame holding and flash back.

  16. Lupus Alma Disk Survey

    Science.gov (United States)

    Ansdell, Megan

    2016-07-01

    We present the first unbiased ALMA survey of both dust and gas in a large sample of protoplanetary disks. We surveyed 100 sources in the nearby (150-200 pc), young (1-2 Myr) Lupus region to constrain M_dust to 2 M_Mars and M_gas to 1 M_Jup. Most disks have masses < MMSN and gas-to-dust ratios < ISM. Such rapid gas depletion may explain the prevalence of super-Earths in the exoplanet population.

  17. Notochord Cells in Intervertebral Disc Development and Degeneration

    Directory of Open Access Journals (Sweden)

    Matthew R. McCann

    2016-01-01

    Full Text Available The intervertebral disc is a complex structure responsible for flexibility, multi-axial motion, and load transmission throughout the spine. Importantly, degeneration of the intervertebral disc is thought to be an initiating factor for back pain. Due to a lack of understanding of the pathways that govern disc degeneration, there are currently no disease-modifying treatments to delay or prevent degenerative disc disease. This review presents an overview of our current understanding of the developmental processes that regulate intervertebral disc formation, with particular emphasis on the role of the notochord and notochord-derived cells in disc homeostasis and how their loss can result in degeneration. We then describe the role of small animal models in understanding the development of the disc and their use to interrogate disc degeneration and associated pathologies. Finally, we highlight essential development pathways that are associated with disc degeneration and/or implicated in the reparative response of the tissue that might serve as targets for future therapeutic approaches.

  18. Disks around young stellar objects

    Indian Academy of Sciences (India)

    ... large groundbased telescopes, mm and radiowave interferometry have been used to image disks around a large number of YSOs revealing disk structure with ever-increasing detail and variety. The disks around YSOs are believed to be the sites of planet formation and a few such associations have now been confirmed.

  19. Identifying Likely Disk-hosting M dwarfs with Disk Detective

    Science.gov (United States)

    Silverberg, Steven; Wisniewski, John; Kuchner, Marc J.; Disk Detective Collaboration

    2018-01-01

    M dwarfs are critical targets for exoplanet searches. Debris disks often provide key information as to the formation and evolution of planetary systems around higher-mass stars, alongside the planet themselves. However, less than 300 M dwarf debris disks are known, despite M dwarfs making up 70% of the local neighborhood. The Disk Detective citizen science project has identified over 6000 new potential disk host stars from the AllWISE catalog over the past three years. Here, we present preliminary results of our search for new disk-hosting M dwarfs in the survey. Based on near-infrared color cuts and fitting stellar models to photometry, we have identified over 500 potential new M dwarf disk hosts, nearly doubling the known number of such systems. In this talk, we present our methodology, and outline our ongoing work to confirm systems as M dwarf disks.

  20. Brown dwarf disks with ALMA

    Energy Technology Data Exchange (ETDEWEB)

    Ricci, L.; Isella, A. [Department of Astronomy, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Testi, L.; De Gregorio-Monsalvo, I. [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching (Germany); Natta, A. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy); Scholz, A., E-mail: lricci@astro.caltech.edu [School of Cosmic Physics, Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland)

    2014-08-10

    We present Atacama Large Millimeter/submillimeter Array continuum and spectral line data at 0.89 mm and 3.2 mm for three disks surrounding young brown dwarfs and very low mass stars in the Taurus star forming region. Dust thermal emission is detected and spatially resolved for all the three disks, while CO(J = 3-2) emission is seen in two disks. We analyze the continuum visibilities and constrain the disks' physical structure in dust. The results of our analysis show that the disks are relatively large; the smallest one has an outer radius of about 70 AU. The inferred disk radii, radial profiles of the dust surface density, and disk to central object mass ratios lie within the ranges found for disks around more massive young stars. We derive from our observations the wavelength dependence of the millimeter dust opacity. In all the three disks, data are consistent with the presence of grains with at least millimeter sizes, as also found for disks around young stars, and confirm that the early stages of the solid growth toward planetesimals occur also around very low-mass objects. We discuss the implications of our findings on models of solids evolution in protoplanetary disks, the main mechanisms proposed for the formation of brown dwarfs and very low-mass stars, as well as the potential of finding rocky and giant planets around very low-mass objects.

  1. Exploring Our Galaxy's Thick Disk

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    What is the structure of the Milky Ways disk, and how did it form? A new study uses giant stars to explore these questions.A View from the InsideSchematic showing an edge-on, not-to-scale view of what we think the Milky Ways structurelookslike. The thick disk is shown in yellow and the thin disk is shown in green. [Gaba p]Spiral galaxies like ours are often observed to have disks consisting of two components: a thin disk that lies close to the galactic midplane, and a thick disk that extends above and below this. Past studies have suggested that the Milky Ways disk hosts the same structure, but our position embedded in the Milky Way makes this difficult to confirm.If we can measure the properties of a broad sample of distant tracer stars and use this to better understand the construction of the Milky Ways disk, then we can start to ask additional questions like, how did the disk components form? Formation pictures for the thick disk generally fall into two categories:Stars in the thick disk formed within the Milky Way either in situ or by migrating to their current locations.Stars in the thick disk formed in satellite galaxies around the Milky Way and then accreted when the satellites were disrupted.Scientists Chengdong Li and Gang Zhao (NAO Chinese Academy of Sciences, University of Chinese Academy of Sciences) have now used observations of giant stars which can be detected out to great distances due to their brightness to trace the properties of the Milky Ways thick disk and address the question of its origin.Best fits for the radial (top) and vertical (bottom) metallicity gradients of the thick-disk stars. [Adapted from Li Zhao 2017]Probing OriginsLi and Zhao used data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) in China to examine a sample of 35,000 giant stars. The authors sorted these stars into different disk components halo, thin disk, and thick disk based on their kinematic properties, and then explored how the orbital and

  2. Vibration of imperfect rotating disk

    Directory of Open Access Journals (Sweden)

    Půst L.

    2011-12-01

    Full Text Available This study is concerned with the theoretical and numerical calculations of the flexural vibrations of a bladed disk. The main focus of this study is to elaborate the basic background for diagnostic and identification methods for ascertaining the main properties of the real structure or an experimental model of turbine disks. The reduction of undesirable vibrations of blades is proposed by using damping heads, which on the experimental model of turbine disk are applied only on a limited number of blades. This partial setting of damping heads introduces imperfection in mass, stiffness and damping distribution on the periphery and leads to more complicated dynamic properties than those of a perfect disk. Calculation of FEM model and analytic—numerical solution of disk behaviour in the limited (two modes frequency range shows the splitting of resonance with an increasing speed of disk rotation. The spectrum of resonance is twice denser than that of a perfect disk.

  3. MRI and discography in traumatic intervertebral disc lesions

    Energy Technology Data Exchange (ETDEWEB)

    Ghanem, Nadir; Uhl, Markus; Elgeti, Florian; Pache, Gregor; Kotter, Elmar; Langer, Mathias [University Hospital Freiburg, Departments of Diagnostic Radiology, Freiburg (Germany); Mueller, Christoph; Markmiller, Max [University Hospital Freiburg, Traumatology, Freiburg (Germany)

    2006-11-15

    In this study we evaluated magnetic resonance imaging (MRI) in trauma patients for assessing traumatised adjacent discs of fractured vertebrae before dorsoventral stabilisation. In a prospective study, MRI of 54 discs was performed with a 1.5-T MRI unit. The preoperative MRI with sagittal T1-W-SE and T2-W-TSE was compared to intraoperative discography, which was carried out on both intervertebral discs adjacent to the fractured vertebrae. Signal alterations, morphological changes in the adjacent discs, fractured vertebrae and associated ligament injuries were evaluated. In 47/54 (87%) of the intervertebral discs, the results of both imaging findings were concordant. The discs adjoining vertebral fractures were normal in 18 cases. Regarding the positive concordant imaging findings, MRI and discography revealed traumatised adjacent cranial and caudal discs in 22 discs. In 7 cases, only the cranial adjacent disc was affected. Moreover, 17 cases of intradiscal bleeding, 13 intraosseous herniations into the fractured vertebrae and 20 anuluar tears were visualised in MRI. Associated ligament injuries were detected in 18 cases. Findings were discordant in eight discs. In six discs, MRI was abnormal, demonstrating signal alterations suggestive of positive imaging findings, whereas discography demonstrated no disc injury. MRI failed to detect disc injury in two discs, whereas discography was positive, showing an irregular intradiscal contrast media distribution. MRI, as a non-invasive method for assessing fractures of the thoraco-lumbar spine, may detect traumatised adjacent intervertebral discs. MRI is superior to intraoperative discography. The performance of MRI of the thoraco-lumbar spine is recommended before dorsoventral stabilisation in trauma patients, as it can reveal additional preoperative information such as fractures, disc and associated ligament injuries. (orig.)

  4. DVD - digital versatile disks

    Energy Technology Data Exchange (ETDEWEB)

    Gaunt, R.

    1997-05-01

    An international standard has emerged for the first true multimedia format. Digital Versatile Disk (by its official name), you may know it as Digital Video Disks. DVD has applications in movies, music, games, information CD-ROMS, and many other areas where massive amounts of digital information is needed. Did I say massive amounts of data? Would you believe over 17 gigabytes on a single piece of plastic the size of an audio-CD? That`s the promise, at least, by the group of nine electronics manufacturers who have agreed to the format specification, and who hope to make this goal a reality by 1998. In this major agreement, which didn`t come easily, the manufacturers will combine Sony and Phillip`s one side double-layer NMCD format with Toshiba and Matsushita`s double sided Super-Density disk. By Spring of this year, they plan to market the first 4.7 gigabyte units. The question is: Will DVD take off? Some believe that read-only disks recorded with movies will be about as popular as video laser disks. They say that until the eraseable/writable DVD arrives, the consumer will most likely not buy it. Also, DVD has a good market for replacement of CD- Roms. Back in the early 80`s, the international committee deciding the format of the audio compact disk decided its length would be 73 minutes. This, they declared, would allow Beethoven`s 9th Symphony to be contained entirely on a single CD. Similarly, today it was agreed that playback length of a single sided, single layer DVD would be 133 minutes, long enough to hold 94% of all feature-length movies. Further, audio can be in Dolby`s AC-3 stereo or 5.1 tracks of surround sound, better than CD-quality audio (16-bits at 48kHz). In addition, there are three to five language tracks, copy protection and parental ``locks`` for R rated movies. DVD will be backwards compatible with current CD-ROM and audio CD formats. Added versatility comes by way of multiple aspect rations: 4:3 pan-scan, 4:3 letterbox, and 16:9 widescreen. MPEG

  5. Hidroxiapatita en la estabilización y fusión intervertebral cervical baja

    Directory of Open Access Journals (Sweden)

    Ramiro Pereira Riverón

    1997-12-01

    Full Text Available Se realizó ensayo clínico el cual incluyó a 10 pacientes con lesiones cervicales bajas (C3/7, traumáticas o degenerativas y que requirieron implantes para sustituir discos intervertebrales, y en los que se utilizaron láminas de hidroxiapatita de 3 y 6 mm de espesor y porosidad de 50 %, de fabricación nacional. En 9 casos se obtuvo estabilidad y osteoconducción adecuadas, evaluadas por medio de controles clínicos y radiológicos. Se verificó en nuestro medio, la eficacia de la hidroxiapatita como implante para lograr la fusión intersomática vertebral, como sustituta eficiente de los injertos óseos autógenos, al evitar sus complicaciones habituales. Se recomienda su empleo y la fabricación de implantes de hidroxiapatita de configuración y dimensiones más específicasIt was conducted a clinical assay of 10 patients with cervical low (C3/7, traumatic or degenerative injuries that required implants to substitute intervertebral disks. Hydroxyapatite laminae 3-6 mm thick with a porosity of 50% made in Cuba were used. Adequate stability and osteoconduction were attained in 9 cases that were evaluated by clinical and radiological controls. The efficiency of hydroxyapatite as an implant to achieve the intersomatic vertebral fusion, and as an efficient substitute of the autogenous bone grafts, was verified in our environment, on preventing its habitual complications. It is recommended its use and the making of hydroxyapatite implants of more specific configuration and dimensions

  6. Comparison of the T2 relaxation time of the temporomandibular joint articular disk between patients with temporomandibular disorders and asymptomatic volunteers.

    Science.gov (United States)

    Kakimoto, N; Shimamoto, H; Chindasombatjaroen, J; Tsujimoto, T; Tomita, S; Hasegawa, Y; Murakami, S; Furukawa, S

    2014-07-01

    T2 relaxation time is a quantitative MR imaging parameter used to detect degenerated cartilage in the knee and lumbar intervertebral disks. We measured the T2 relaxation time of the articular disk of the temporomandibular joint in patients with temporomandibular disorders and asymptomatic volunteers to demonstrate an association between T2 relaxation time and temporomandibular disorder MR imaging findings. One hundred forty-four patients with temporomandibular disorders and 17 volunteers were enrolled in this study. An 8-echo spin-echo sequence for measuring the T2 relaxation times was performed in the closed mouth position, and the T2 relaxation time of the entire articular disk was measured. Patients were classified according to the articular disk location and function, articular disk configuration, presence of joint effusion, osteoarthritis, and bone marrow abnormalities. The T2 relaxation time of the entire articular disk was 29.3 ± 3.8 ms in the volunteer group and 30.7 ± 5.1 ms in the patient group (P = .177). When subgroups were analyzed, however, the T2 relaxation times of the entire articular disk in the anterior disk displacement without reduction group, the marked or extensive joint effusion group, the osteoarthritis-positive group, and the bone marrow abnormality-positive group were significantly longer than those in the volunteer group (P temporomandibular joint in patients with progressive temporomandibular disorders were longer than those of healthy volunteers. © 2014 by American Journal of Neuroradiology.

  7. Intervertebral disc cells produce tumor necrosis factor alpha, interleukin-1beta, and monocyte chemoattractant protein-1 immediately after herniation: an experimental study using a new hernia model.

    Science.gov (United States)

    Yoshida, Masakazu; Nakamura, Takafumi; Sei, Akira; Kikuchi, Taro; Takagi, Katsumasa; Matsukawa, Akihiro

    2005-01-01

    A new hernia model that simulates human disc herniations was developed in rabbits. The herniated discs were examined by gross appearance and histology and production of tumor necrosis factor alpha, interleukin-1beta, and monocyte chemoattractant protein-1 was investigated. To clarify the early mechanism of spontaneous herniated disc resorption. Macrophage infiltration in herniated discs is essential for disc resorption. However, surgically removed human herniated disc tissues and existing animal hernia models are not suitable for analyzing the mechanism of macrophage infiltration. Recently, we have demonstrated that intervertebral disc cells are capable of producing monocyte chemoattractant protein-1, a potent macrophage chemoattractant, after stimulation with tumor necrosis factor alpha and interleukin-1beta. Intervertebral disc herniations were surgically developed in rabbits using a new technique. The herniated discs were excised at appropriate time intervals after the surgery, and the size and histologic findings were examined. Expressions of tumor necrosis factor alpha, interleukin-1beta, and monocyte chemoattractant protein-1 in herniated discs were investigated immunohistochemically. A new rabbit model of disc herniation was established. The herniated discs spontaneously reduced in size by 12 weeks postsurgery. Infiltrating cells, mainly composed of macrophages, were observed from day 3. Immunohistochemically, intervertebral disc cells in the herniated discs produced tumor necrosis factor alpha and interleukin-1beta on day 1, followed by monocyte chemoattractant protein-1 on day 3. The new hernia model appears to be very useful for studying herniated disc resorption. Intervertebral disc cells may produce inflammatory cytokines/chemokine immediately after the onset of disc herniation, possibly triggering subsequent macrophage infiltration that leads to disc resorption.

  8. Audit: Automated Disk Investigation Toolkit

    Directory of Open Access Journals (Sweden)

    Umit Karabiyik

    2014-09-01

    Full Text Available Software tools designed for disk analysis play a critical role today in forensics investigations. However, these digital forensics tools are often difficult to use, usually task specific, and generally require professionally trained users with IT backgrounds. The relevant tools are also often open source requiring additional technical knowledge and proper configuration. This makes it difficult for investigators without some computer science background to easily conduct the needed disk analysis. In this paper, we present AUDIT, a novel automated disk investigation toolkit that supports investigations conducted by non-expert (in IT and disk technology and expert investigators. Our proof of concept design and implementation of AUDIT intelligently integrates open source tools and guides non-IT professionals while requiring minimal technical knowledge about the disk structures and file systems of the target disk image.

  9. Identification of ventrolateral intramedullary intervertebral disc herniation in a dog

    Directory of Open Access Journals (Sweden)

    Masato Kitagawa

    2012-09-01

    Full Text Available A 10-year-old male cross-breed dog was brought to Nihon University Animal Hospital with a history of acute onset of paralysis in the pelvic limbs 13 days previously. Magnetic resonance imaging revealed an intramedullary linear tract in the spinal cord at the thoracic vertebrae 12–13 region, which appeared hyperintense on T2-weighted images, but was hypointense and isointense on T1-weighted images when compared with normal parenchyma of the spinal cord. A hemilaminectomy was performed and a blob of what appeared to be fibrous tissue was found adhering to the surface of the dura mater. The diameter of the blob was about 4 mm. A durotomy was performed over the affected area and chondroid material was found within the spinal cord. Material from the nucleus pulposus penetrated the dura mater from the ventral aspect of the spinal cord in previously reported intramedullary intervertebral disc herniation cases, but, in this case, penetration occurred from the left ventrolateral aspect and progressed through to the right lateral aspect, forming a visible blob of what appeared to be fibrous tissue on the surface of the dura mater at the exit point. To the best of our knowledge, this was the first case report of an intramedullary intervertebral disc herniation originating from the ventrolateral aspect of the spinal cord in a dog.

  10. A radiological study on lumbar herniated intervertebral disc diseases

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Hae Soon [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1974-10-15

    During 5 years and 8 months, from September 1968 to May 1974, myelographic studies followed by operation were carried out on 118 cases of lumbar HIVD at Seoul National University Hospital. The myelographic findings and operative findings were analyzed and following conclusions were obtained. 1. The sex ratio wa 75 males to 43 females. 2. Among the 118 cases, myelographic findings were consisted of the unilateral defect; 78 cases (67.0%), central defect: 30 cases (25.5%), and, bilateral defects; 10 cases (8.5%) respectively. 3. Among the 118 cases, the greatest incidence was L4-L5 disc space: 87 cases (73.7%) and next incidence was L5-S1 disc space: 25 cases (21.2%). 4. Among the 118 cases of lumbar herniated intervertebral disc disease, the false positive was 8 cases (6.8%) and diagnostic accuracy of myelography was 91.5%. 5. Plain radiography has little value in diagnosis of lumbar herniated intervertebral disc disease among 118 cases, about 30% show significant sign in plain film study.

  11. IBM 3390 Hard Disk Platter

    CERN Multimedia

    1991-01-01

    The 3390 disks rotated faster than those in the previous model 3380. Faster disk rotation reduced rotational delay (ie. the time required for the correct area of the disk surface to move to the point where data could be read or written). In the 3390's initial models, the average rotational delay was reduced to 7.1 milliseconds from 8.3 milliseconds for the 3380 family.

  12. Intraobserver, interobserver, and intermethod agreement for results of myelography, computed tomography-myelography, and low-field magnetic resonance imaging in dogs with disk-associated wobbler syndrome.

    Science.gov (United States)

    De Decker, Steven; Gielen, Ingrid M V L; Duchateau, Luc; Corzo-Menéndez, Nuria; van Bree, Henri J J; Kromhout, Kaatje; Bosmans, Tim; Van Ham, Luc M L

    2011-06-15

    To determine intraobserver, interobserver, and intermethod agreement for results of myelography, computed tomography-myelography (CTM), and low-field magnetic resonance imaging (MRI) in dogs with disk-associated wobbler syndrome (DAWS). Prospective cross-sectional study. 22 dogs with DAWS. All dogs underwent myelography, CTM, and low-field MRI. Each imaging study was interpreted twice by 4 observers who were blinded to signalment and clinical information of the patients. The following variables were assessed by all 3 techniques: number, site, and direction of spinal cord compressions; narrowed intervertebral disk spaces; vertebral body abnormalities; spondylosis deformans; and abnormal articular facets. Intervertebral foraminal stenosis was assessed on CTM and MRI images. Intraobserver, interobserver, and intermethod agreement were calculated by κ and weighted κ statistics. There was very good to good intraobserver agreement for most variables assessed by myelography and only moderate intraobserver agreement for most variables assessed by CTM and low-field MRI. There was moderate to fair interobserver and intermethod agreement for most variables assessed by the 3 diagnostic techniques. There was very good or good intraobserver, interobserver, or intermethod agreement for the site and direction of the worst spinal cord compression as assessed by all the imaging modalities; abnormal articular facets and intervertebral foraminal stenosis were the least reliably assessed variables, with poor interobserver agreement regardless of imaging modality used. There was considerable variation in image interpretation among observers and between use of various imaging modalities; these imaging techniques should be considered complementary in assessment of dogs with DAWS.

  13. Disk storage at CERN

    CERN Document Server

    Mascetti, L; Chan, B; Espinal, X; Fiorot, A; Labrador, H Gonz; Iven, J; Lamanna, M; Presti, G Lo; Mościcki, JT; Peters, AJ; Ponce, S; Rousseau, H; van der Ster, D

    2015-01-01

    CERN IT DSS operates the main storage resources for data taking and physics analysis mainly via three system: AFS, CASTOR and EOS. The total usable space available on disk for users is about 100 PB (with relative ratios 1:20:120). EOS actively uses the two CERN Tier0 centres (Meyrin and Wigner) with 50:50 ratio. IT DSS also provide sizeable on-demand resources for IT services most notably OpenStack and NFS-based clients: this is provided by a Ceph infrastructure (3 PB) and few proprietary servers (NetApp). We will describe our operational experience and recent changes to these systems with special emphasis to the present usages for LHC data taking, the convergence to commodity hardware (nodes with 200-TB each with optional SSD) shared across all services. We also describe our experience in coupling commodity and home-grown solution (e.g. CERNBox integration in EOS, Ceph disk pools for AFS, CASTOR and NFS) and finally the future evolution of these systems for WLCG and beyond.

  14. Disks around young stellar objects

    Indian Academy of Sciences (India)

    (1734), Immanuel Kant (1755) and by Pierre-Simon Laplace (1796) in the 18th century. 4. The circumstantial evidence for circumstellar disks. Till around early 1980s, the evidence for the existence of circumstellar disks around YSOs had been indirect, based on the interpretation of optical-infrared spectral energy distribu-.

  15. The impact of the artificial intervertebral disc on functioning the lumbar spine

    Directory of Open Access Journals (Sweden)

    Mańsko M.

    2015-12-01

    Full Text Available In the hereby thesis the anatomy of the lumbar vertebra and intervertebral disc were presented. Functioning and kinematics of the spine and intervertebral forces were described.Full three – dimensional model of the lumbar vertebrae L2 – L4 was created. On the basis of it model of artificial intervertebral disc was constructed (between L2 and L3. The simplified model of vertebra L2 was formulated via finite elements method. Processed model has been used for biomechanical analysis.Strength calculations were made and appropriate conclusions were drawn. Presented results show behavior influenced of three – dimensional model of the lumbar vertebra with artificial intervertebral disc by operation of loads.

  16. Aging and degeneration of the intervertebral disc: review of basic science

    Directory of Open Access Journals (Sweden)

    Josemberg da Silva Baptista

    2015-06-01

    Full Text Available Currently there is a growing interest in the study of intervertebral discs due to loss of manpower brought to society by low back and neck pains. These papers seek to delineate the difference between normal aging and disc degeneration, trying to understand what factor would be determining for the second condition. Thus, the morphology field was expanded and knowledge on the structure of intervertebral discs currently uses the research field of cell and molecular biology, and genetics. The results indicate that regardless of age or condition, the intervertebral disc undergoes long and extensive remodeling of its constituents, which are influenced by several factors: environmental, soluble, cell growth and extracellular matrix. In this literature review we describe the biological characteristics of the cervical and lumbar intervertebral disc with a focus on basic science of aging and degeneration, selecting the latest findings and discussions of the area, which influence future research and clinical thoughts.

  17. Protective Effect of Ligustrazine on Lumbar Intervertebral Disc Degeneration of Rats Induced by Prolonged Upright Posture

    Directory of Open Access Journals (Sweden)

    Qian-Qian Liang

    2014-01-01

    Full Text Available Most chronic low back pain is the result of degeneration of the lumbar intervertebral disc. Ligustrazine, an alkaloid from Chuanxiong, reportedly is able to relieve pain, suppress inflammation, and treat osteoarthritis and it has the protective effect on cartilage and chondrocytes. Therefore, we asked whether ligustrazine could reduce intervertebral disc degeneration. To determine the effect of ligustrazine on disc degeneration, we applied a rat model. The intervertebral disc degeneration of the rats was induced by prolonged upright posture. We found that pretreatment with ligustrazine for 1 month recovered the structural distortion of the degenerative disc; inhibited the expression of type X collagen, matrix metalloproteinase (MMP-13, and MMP3; upregulated type II collagen; and decreased IL-1β, cyclooxygenase (COX-2, and inducible nitric oxide synthase (iNOS expression. In conclusion, ligustrazine is a promising agent for treating lumbar intervertebral disc degeneration disease.

  18. Biomechanical and rheological characterization of mild intervertebral disc degeneration in a large animal model

    NARCIS (Netherlands)

    Detiger, Suzanne E. L.; Hoogendoorn, Roel J. W.; van der Veen, Albert J.; van Royen, Barend J.; Helder, Marco N.; Koenderink, Gijsje H.; Smit, Theo H.

    2013-01-01

    Biomechanical properties of healthy and degenerated nucleus pulposus (NP) are thought to be important for future regenerative strategies for intervertebral disc (IVD) repair. However, which properties are pivotal as design criteria when developing NP replacement materials is ill understood.

  19. Disk Modeling: Arts and Phenomenology

    Science.gov (United States)

    Gayley, K. G.; Porter, J. M.

    2005-11-01

    This article summarizes the focus session on disk modeling arts and phenomenology, which was devoted to the types of interesting physics a disk modeler may wish to include, and how best to include it. It is assumed that the modeling goal is to guide the process of falsification of various hypotheses with data accessible by existing and planned observations. Appropriate modeling choices depend on the conditions and aspects of the problem under study, but the expectation is that observations will yield to correct interpretation only when the key physics is properly understood, and effectively simulated in the models. This focus review first sketches several potentially relevant phenomena that disk modelers may wish to incorporate, especially in regard to the role of magnetic vs. inertial support of disks, and the source of disk angular momentum. It then concludes with some comments on effective numerical modeling strategies for incorporating these effects.

  20. Association between apparent diffusion coefficient and intervertebral disc degeneration in patients with ankylosing spondylitis

    OpenAIRE

    Resorlu, Mustafa; Gokmen,Ferhat; Resorlu, Hatice; Adam, Gurhan; Akbal, Ayla; Cevizci, Sibel; Sariyildirim, Abdullah; Savas, Yilmaz; Guven, Mustafa; Aras, Adem Bozkurt

    2015-01-01

    Purpose: To assess the relation between ankylosing spondylitis (AS) and degenerative disc disease emerging in association with various intrinsic and extrinsic factors and to evaluate the correlation between degree of degeneration in intervertebral discs and apparent diffusion coefficient (ADC) values. Methods: Thirty-five patients with AS and a control group of 35 patients were included in the study. Three hundred fifty intervertebral discs were assessed in terms of degeneration by analyzing ...

  1. [Mistakes and countermeasures in diagnosis and treatment of prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Xu, Lin-bo

    2007-06-01

    The mistakes in clinical diagnosis and treatment due to dealing with symptoms, signs and imaging data in isolation, and unclear differentiation of relative diseases are found by reviewing definition and cause of disease and pathogenesis of prolapse of lumbar intervertebral disc, so as to probe into mistakes and countermeasures in diagnosis and treatment of prolapse of lumbar intervertebral disc. Only combined analysis of clinical symptoms, signs and imaging data, can correct diagnosis and treatment be made.

  2. Indigo carmine for the selective endoscopic intervertebral nuclectomy.

    Science.gov (United States)

    Kim, Inn-Se; Kim, Kyung-Hoon; Shin, Sang-Wook; Kim, Tae-Kyun; Kim, Jeung-Il

    2005-08-01

    This study was undertaken to prove that the selectively infiltrated parts of nucleus pulposus with indigo carmine was degenerated parts of nucleus pulposus. This study was done, between August and October 2002, in 5 patients, who received endoscopic discectomy, due to intervertebral disc herniation. Discogram was done with mixture of indigo carmine and radioactive dye. Blue discolored part was removed through endoscope, and small undiscolored part was removed together for the control. The two parts were stained with hematoxylin and eosin and compared under the microscope. Undiscolored part was normal nucleus pulposus, composed of chondrocytes with a matrix of type II collagen and proteoglycan, mainly aggrecan. However, in discolored part, slits with destruction of collagen fiber array and ingrowth of vessel and nerve were observed. Using indigo carmine in endoscopic discectomy gives us selective removal of degenerated disc.

  3. Matrisome Profiling During Intervertebral Disc Development And Ageing.

    Science.gov (United States)

    Caldeira, Joana; Santa, Cátia; Osório, Hugo; Molinos, Maria; Manadas, Bruno; Gonçalves, Raquel; Barbosa, Mário

    2017-09-14

    Intervertebral disc (IVD) degeneration is often the cause of low back pain. Degeneration occurs with age and is accompanied by extracellular matrix (ECM) depletion, culminating in nucleus pulpous (NP) extrusion and IVD destruction. The changes that occur in the disc with age have been under investigation. However, a thorough study of ECM profiling is needed, to better understand IVD development and age-associated degeneration. As so, iTRAQ LC-MS/MS analysis of foetus, young and old bovine NPs, was performed to define the NP matrisome. The enrichment of Collagen XII and XIV in foetus, Fibronectin and Prolargin in elder NPs and Collagen XI in young ones was independently validated. This study provides the first matrisome database of healthy discs during development and ageing, which is key to determine the pathways and processes that maintain disc homeostasis. The factors identified may help to explain age-associated IVD degeneration or constitute putative effectors for disc regeneration.

  4. Bovine annulus fibrosus cell lines isolated from intervertebral discs

    Directory of Open Access Journals (Sweden)

    Petra Kraus

    2016-12-01

    Full Text Available The adult bovine (Bos taurus intervertebral disc is primarily comprised of two major tissue types: The outer annulus fibrosus (AF and the central nucleus pulposus (NP. We isolated several primary cell lineages of passage (P 0 cells from the AF tissue omitting typically used enzymatic tissue digestion protocols. The cells grow past p10 without signs of senescence in DMEM + 10% FCS on 0.1% gelatin coated/uncoated surfaces of standard cell culture plates and survive freeze-thawing. Preliminary analysis of the AF derived cells for expression of the two structural genes Col1a1 and Col2a1 was performed by PISH recapitulating the expression observed in vivo.

  5. Comparison of Multi Disk Exponential Gas Distribution vs. Single Disk

    Science.gov (United States)

    Rao, Erica; O'Brien, James

    2013-04-01

    In fitting galactic rotation curves to data, most standard theories make use of a single exponential disk approximation of the gas distribution to account for the HI synthesis data observed at various radio telescope facilities. We take a sample of surface brightness profiles from The HI Nearby Galaxy Survey (THINGS), and apply both single disk exponentials and Multi-Disk exponentials, and use these various models to see how the modelling procedure changes the Newtonian prediction of the mass of the galaxy. Since the missing mass problem has not been fully explained in large spiral galaxies, different modelling procedures could account for some of the missing matter.

  6. Heparanase isoform expression and extracellular matrix remodeling in intervertebral disc degenerative disease

    Directory of Open Access Journals (Sweden)

    Luciano Miller Reis Rodrigues

    2011-01-01

    Full Text Available OBJECTIVE: To determine the molecules involved in extracellular matrix remodeling and to identify and quantify heparanase isoforms present in herniated and degenerative discs. INTRODUCTION: Heparanase is an endo-beta-glucuronidase that specifically acts upon the heparan sulfate chains of proteoglycans. However, heparanase expression in degenerative intervertebral discs has not yet been evaluated. Notably, previous studies demonstrated a correlation between changes in the heparan sulfate proteoglycan pattern and the degenerative process associated with intervertebral discs. METHODS: Twenty-nine samples of intervertebral degenerative discs, 23 samples of herniated discs and 12 samples of non-degenerative discs were analyzed. The expression of both heparanase isoforms (heparanase-1 and heparanase-2 was evaluated using immunohistochemistry and real-time RT-PCR analysis. RESULTS: Heparanase-1 and heparanase-2 expression levels were significantly higher in the herniated and degenerative discs in comparison to the control tissues, suggesting a possible role of these proteins in the intervertebral degenerative process. CONCLUSION: The overexpression of heparanase isoforms in the degenerative intervertebral discs and the herniated discs suggests a potential role of both proteins in the mediation of inflammatory processes and in extracellular matrix remodeling. The heparanase-2 isoform may be involved in normal metabolic processes, as evidenced by its higher expression in the control intervertebral discs relative to the expression of heparanase-1.

  7. A developmental transcriptomic analysis of Pax1 and Pax9 in embryonic intervertebral disc development

    Directory of Open Access Journals (Sweden)

    V. Sivakamasundari

    2017-02-01

    Full Text Available Pax1 and Pax9 play redundant, synergistic functions in the patterning and differentiation of the sclerotomal cells that give rise to the vertebral bodies and intervertebral discs (IVD of the axial skeleton. They are conserved in mice and humans, whereby mutation/deficiency of human PAX1/PAX9 has been associated with kyphoscoliosis. By combining cell-type-specific transcriptome and ChIP-sequencing data, we identified the roles of Pax1/Pax9 in cell proliferation, cartilage development and collagen fibrillogenesis, which are vital in early IVD morphogenesis. Pax1 is up-regulated in the absence of Pax9, while Pax9 is unaffected by the loss of Pax1/Pax9. We identified the targets compensated by a single- or double-copy of Pax9. They positively regulate many of the cartilage genes known to be regulated by Sox5/Sox6/Sox9 and are connected to Sox5/Sox6 by a negative feedback loop. Pax1/Pax9 are intertwined with BMP and TGF-B pathways and we propose they initiate expression of chondrogenic genes during early IVD differentiation and subsequently become restricted to the outer annulus by the negative feedback mechanism. Our findings highlight how early IVD development is regulated spatio-temporally and have implications for understanding kyphoscoliosis.

  8. Intervertebral disc classification by its degree of degeneration from T2-weighted magnetic resonance images.

    Science.gov (United States)

    Castro-Mateos, Isaac; Hua, Rui; Pozo, Jose M; Lazary, Aron; Frangi, Alejandro F

    2016-09-01

    The primary goal of this article is to achieve an automatic and objective method to compute the Pfirrmann's degeneration grade of intervertebral discs (IVD) from MRI. This grading system is used in the diagnosis and management of patients with low back pain (LBP). In addition, biomechanical models, which are employed to assess the treatment on patients with LBP, require this grading value to compute proper material properties. T2-weighted MR images of 48 patients were employed in this work. The 240 lumbar IVDs were divided into a training set (140) and a testing set (100). Three experts manually classified the whole set of IVDs using the Pfirrmann's grading system and the ground truth was selected as the most voted value among them. The developed method employs active contour models to delineate the boundaries of the IVD. Subsequently, the classification is achieved using a trained Neural Network (NN) with eight designed features that contain shape and intensity information of the IVDs. The classification method was evaluated using the testing set, resulting in a mean specificity (95.5 %) and sensitivity (87.3 %) comparable to those of every expert with respect to the ground truth. Our results show that the automatic method and humans perform equally well in terms of the classification accuracy. However, human annotations have inherent inter- and intra-observer variabilities, which lead to inconsistent assessments. In contrast, the proposed automatic method is objective, being only dependent on the input MRI.

  9. Hydrogen Cyanide In Protoplanetary Disks

    Science.gov (United States)

    Walker, Ashley L.; Oberg, Karin; Cleeves, L. Ilsedore

    2018-01-01

    The chemistry behind star and planet formation is extremely complex and important in the formation of habitable planets. Life requires molecules containing carbon, oxygen, and importantly, nitrogen. Hydrogen cyanide, or HCN, one of the main interstellar nitrogen carriers, is extremely dangerous here on Earth. However, it could be used as a vital tool for tracking the chemistry of potentially habitable planets. As we get closer to identifying other habitable planets, we must understand the beginnings of how those planets are formed in the early protoplanetary disk. This project investigates HCN chemistry in different locations in the disk, and what this might mean for forming planets at different distances from the star. HCN is a chemically diverse molecule. It is connected to the formation for other more complex molecules and is commonly used as a nitrogen tracer. Using computational chemical models we look at how the HCN abundance changes at different locations. We use realistic and physically motivated conditions for the gas in the protoplanetary disk: temperature, density, and radiation (UV flux). We analyze the reaction network, formation, and destruction of HCN molecules in the disk environment. The disk environment informs us about stability of habitable planets that are created based on HCN molecules. We reviewed and compared the difference in the molecules with a variety of locations in the disk and ultimately giving us a better understanding on how we view protoplanetary disks.

  10. 8-inch IBM floppy disk

    CERN Multimedia

    1971-01-01

    The 8-inch floppy disk was a magnetic storage disk for the data introduced commercially by IBM in 1971. It was designed by an IBM team as an inexpensive way to load data into the IBM System / 370. Plus it was a read-only bare disk containing 80 KB of data. The first read-write version was introduced in 1972 by Memorex and could contain 175 KB on 50 tracks (with 8 sectors per track). Other improvements have led to various coatings and increased capacities. Finally, it was surpassed by the mini diskette of 5.25 inches introduced in 1976.

  11. Clinical outcome following DIAM implantation for symptomatic lumbar internal disk disruption: a 3-year retrospective analysis

    Directory of Open Access Journals (Sweden)

    Lu K

    2016-10-01

    Full Text Available Kang Lu,1 Po-Chou Liliang,1 Hao-Kuang Wang,1 Jui-Sheng Chen,1 Te-Yuan Chen,1 Ruyi Huang,2 Han-Jung Chen1,3 1Department of Neurosurgery, E-Da Hospital, 2Department of Family Medicine, E-Da Hospital, 3Department of Neurosurgery, E-Da Cancer Hospital, College of Medicine, I-Shou University, Kaohsiung, Taiwan Background/objective: Internal disk disruption (IDD, an early event of lumbar disk degeneration, is the most common cause of low back pain. Since increased intradiskal pressure (IDP is associated with symptoms and progression of disk degeneration, unloading a painful disk with an interspinous process device (IPD is a rational treatment option. The goal of this study was to evaluate the effectiveness of dynamic stabilization with an IPD in the treatment of symptomatic IDD of the lumbar spine. Patients and methods: Patients with symptomatic IDD were treated with implantation of an IPD, the device for intervertebral assisted motion (DIAM. Diagnosis of IDD was based on typical MRI finding of posterior annular high-intensity zone and positive provocative test on discography. IDP was analyzed intraoperatively. Axial back and leg pain was evaluated with visual analog scale, functional status with Oswestry Disability Index, and final clinical outcomes with Odom criteria. Data from 34 patients followed up for at least 3 years were collected. Results: DIAM implantation significantly reduced IDP (n=11, P<0.0001. All 34 patients reported symptom relief. Thirty-one patients (91% remained symptom free until the last follow-ups. Three patients (9% experienced recurrence of pain, of which the causes were unrelated to the IDD or surgery. Disk status at the DIAM-implanted segments remained stable. Segmental flexion/extension mobility was preserved in 27 of 30 patients with preoperative mobility. No proximal or distal adjacent segment degeneration was observed. The final clinical outcomes were excellent/good in 31 and fair/poor in three patients. Conclusion: For

  12. The Tilt between Acretion Disk and Stellar Disk

    Indian Academy of Sciences (India)

    ... large sample of Type 2 AGNs selected from Sloan Digital Sky Survey (SDSS, York et al. 2000) to a control galaxy sample. Given that the Type 2 AGN fraction is in the range of 70–90 percent for low luminosity AGNs as a priori, we find that the mean tilt between the accretion disk and stellar disk is ∼ 30 degrees (Shen et al.

  13. Rabbit model of intervertebral disc degeneration by external compression device characterized by X-ray, MRI, histology, and cell viability

    Directory of Open Access Journals (Sweden)

    Ismail Ismail

    2006-12-01

    Full Text Available Appropriate experimental animal models, which mimic the degenerative process occurring in human intervertebral disc (IVD breakdown and can be used for new treatment studies such as tissue engineering or disc distraction are lacking. We studied the external compression device that used by Kroeber et al to create intervertebral disc degeneration in rabbit model characterized by X-ray, MRI, Histology, and Cell Viability. Ten NZW rabbit were randomly assigned to one of five groups. Intervertebral disc VL4-L5 are compressed using an external loading device, 1.9 MPa. First group rabbit are loaded for 14 days, second loaded for 28 days, thirth group are loaded for 14 days, and unloaded for 14 days, fourth group loaded for 28 days and unloaded for 28 days. The fifth group, rabbits underwent a sham operation. Additional, rabbits were used as sample for cell viability study. In disc height : sample in group one have biggest decreasing of disc height, that is 23.9 unit. In MRI assessment, the worst grade is grade 3. In histological score, the worst group is group three (58.69, and the best is group 4 (45.69. Group one have the largest dead cell, that are 403.5, and the smallest is group four (124.75. Trypan blue staining showed that group four have better viable cell (91.1 compare than group three (86.4. The study conclude disc degeneration can be created by external axial loading for 14 days in rabbit intervertebral disc. Duration of 28 days unloading gave better result for cells to recover. (Med J Indones 2006; 15:199-207  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Keywords: Rabbit model –intervertebral disc degeneration- external compression device-X-ray, MRI, Histology, and Cell viabilty /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso

  14. Link-N: The missing link towards intervertebral disc repair is species-specific.

    Directory of Open Access Journals (Sweden)

    Frances C Bach

    Full Text Available Degeneration of the intervertebral disc (IVD is a frequent cause for back pain in humans and dogs. Link-N stabilizes proteoglycan aggregates in cartilaginous tissues and exerts growth factor-like effects. The human variant of Link-N facilitates IVD regeneration in several species in vitro by inducing Smad1 signaling, but it is not clear whether this is species specific. Dogs with IVD disease could possibly benefit from Link-N treatment, but Link-N has not been tested on canine IVD cells. If Link-N appears to be effective in canines, this would facilitate translation of Link-N into the clinic using the dog as an in vivo large animal model for human IVD degeneration.This study's objective was to determine the effect of the human and canine variant of Link-N and short (s Link-N on canine chondrocyte-like cells (CLCs and compare this to those on already studied species, i.e. human and bovine CLCs. Extracellular matrix (ECM production was determined by measuring glycosaminoglycan (GAG content and histological evaluation. Additionally, the micro-aggregates' DNA content was measured. Phosphorylated (p Smad1 and -2 levels were determined using ELISA.Human (sLink-N induced GAG deposition in human and bovine CLCs, as expected. In contrast, canine (sLink-N did not affect ECM production in human CLCs, while it mainly induced collagen type I and II deposition in bovine CLCs. In canine CLCs, both canine and human (sLink-N induced negligible GAG deposition. Surprisingly, human and canine (sLink-N did not induce Smad signaling in human and bovine CLCs. Human and canine (sLink-N only mildly increased pSmad1 and Smad2 levels in canine CLCs.Human and canine (sLink-N exerted species-specific effects on CLCs from early degenerated IVDs. Both variants, however, lacked the potency as canine IVD regeneration agent. While these studies demonstrate the challenges of translational studies in large animal models, (sLink-N still holds a regenerative potential for humans.

  15. Growth and Differentiation Factor-5 Contributes to the Structural and Functional Maintenance of the Intervertebral Disc

    Directory of Open Access Journals (Sweden)

    Chencheng Feng

    2015-01-01

    Full Text Available Intervertebral disc degeneration (IDD is a widely recognized contributor to low back pain (LBP. The Prevention or reversal of IDD is a potential treatment for LBP. Unfortunately, current treatments for IDD are aimed at relieving symptoms rather than regenerating disc structure or function. Recently, the injection of growth factors and mesenchymal stem cell (MSC transplantation have been shown to be promising biological therapies for IDD. Growth factors stimulate the proliferation of and matrix synthesis by intervertebral disc (IVD cells, leading to the regeneration of degenerative discs. Growth factors, hypoxia and co-culture with nucleus pulposus (NP cells induce MSCs to differentiate toward an NP-like phenotype, which can increase the number of functional cells in the IVD or enhance the function of endogenous disc cells to facilitate IVD regeneration. Therefore, the emerging roles of growth factors in IVD regeneration have piqued the interest of researchers. Growth factors including transforming growth factor-β (TGF-β, fibroblast growth factor (FGF, insulin-like growth factor-1 (IGF-1 and growth and differentiation factor-5 (GDF-5, among others, have been demonstrated to enhance anabolism in IVD cells and to induce NP-like differentiation of MSCs. However, the injection of TGF, IGF and FGF into human IVDs may induce unwanted blood vessel ingrowth, which accelerates the process of IDD, the injection of GDF-5 may not have the same effect. This finding suggests that GDF-5 is a preferable growth factor for use in IDD treatment compared with TGF, IGF and FGF. The GDF-5 gene is one of the few growth factor genes that have been found to be associated with IDD thus far; moreover, the GDF-5 gene defects lead to collagen and proteoglycan abnormalities in discs in mice, suggesting that GDF-5 contributes to the structural and functional maintenance of the IVD. This review is focused on the functions of GDF-5 in the IVD and on the association between GDF

  16. [Application of the puncture laser diskectomy in the treatment of multiple hernias of sacro-iliac intervertebral disks].

    Science.gov (United States)

    Pedachenko, E G; Khizhniak, M V; Tanaseĭchuk, A F; Kulikov, V D

    2000-05-01

    In 144 patients with discogenic lumbosacralic radiculitis the puncture laser discectomy was performed on several levels independently or in combination with open operative intervention. High efficacy of treatment was noted.

  17. Heating of protostellar accretion disks

    Science.gov (United States)

    de Campos, R. R.; Jatenco-Pereira, V.

    2017-07-01

    The magneto-rotational instability (MRI) is believed to be the mechanism responsible for a magneto-hydrodynamic turbulence that could lead to the accretion observed in protoplanetary disks. The need of a minimum amount of ionization in protostellar accretion disks is necessary for the MRI to take place. There are in the literature several studies that include the damping of Alfvén waves as an additional heating source besides the viscous heating mechanism in a geometrically thin and optically thick disk. The damping of the waves transfers energy to the disk increasing the temperature and consequently its ionization fraction, making possible the presence of the MRI in a large part of the disk. We analyzed the contribution of non-ideal effects such as Ohmic and ambipolar diffusion for the disk heating and compare these heating rates with those obtained by damping of Alfvén waves. In order to study these non-ideal effects, we have estimated the radiation emission of each effect through the energy conservation equation, and associated each emission with a black body radiation, which enabled us to assign a temperature contribution of each effect. Using the ATHENA code we were able to simulate the disk at different radial distances, and estimate the electric current density needed to calculate the radiation emission associated with each effect. Once we have those data, we were able to compare the results with other heating sources, like viscosity and Alfvén waves damping, and we concluded that the Ohmic and ambipolar diffusions do not heat the disk in any significant way.

  18. Acid-sensing ion channel 1a regulates the survival of nucleus pulposus cells in the acidic environment of degenerated intervertebral discs

    Directory of Open Access Journals (Sweden)

    Feng Cai

    2016-08-01

    Conclusion: The present findings suggest that further understanding of ASIC1a functionality may provide not only a novel insight into intervertebral disc biology but also a novel therapeutic target for intervertebral disc degeneration.

  19. Intervertebral foramen size and volume changes in low grade, low dysplasia isthmic spondylolisthesis.

    Science.gov (United States)

    Spivak, Jeffrey M; Kummer, Frederick J; Chen, Deyu; Quirno, Martin; Kamerlink, Jonathan R

    2010-09-15

    Anatomic study. The purpose of this study is to determine the effect of the slip amount, slip angle, and disc height on the geometry of the L5 foramen in low-grade, low-dysplasia isthmic L5 spondylolisthesis using a human cadaveric model. Radicular pain and varying degrees of nerve root dysfunction are present in many adult isthmic spondylolisthesis patients and can be the result of compression of the L5 root within its foramen. The intervertebral foramens of six L5 vertebra and sacrum cadaver specimens had a standardized pars defect created and were mounted on an adjustable frame. Plasticene molds of the foramens were made by varying sagittal translocation (0%, 12.5%, 25%, and 50%), slip angle (kyphotic 10° and lordotic 0°, 10°, 20°, and 30°), and disc height (0, 5, and 10 mm). The volume of each mold was measured. The surface area was determined by sagittally slicing on a microtome the mold and each section's face was measured by computer image analysis. The area and volume of the foramen at a sagittal slip of 0%, slip angle of 0°, and 0 mm disc height were used as a control. As disc height decreased from 10 to 5 mm, 10 to 0 mm, and 5 to 0 mm, the foramen area and volume significantly decreased (P spondylolisthesis. Slip angle changes affected foramen area to a lesser degree. Surgical treatment strategies should consider restoration of disc height in cases with foraminal stenosis.

  20. Covering and piercing disks with two centers

    KAUST Repository

    Ahn, Heekap

    2013-04-01

    We give exact and approximation algorithms for two-center problems when the input is a set D of disks in the plane. We first study the problem of finding two smallest congruent disks such that each disk in D intersects one of these two disks. Then we study the problem of covering the set D by two smallest congruent disks. © 2012 Elsevier B.V.

  1. Covering and piercing disks with two centers

    KAUST Repository

    Ahn, Heekap

    2011-01-01

    We consider new versions of the two-center problem where the input consists of a set D of disks in the plane. We first study the problem of finding two smallest congruent disks such that each disk in intersects one of these two disks. Then we study the problem of covering the set D by two smallest congruent disks. We give exact and approximation algorithms for these versions. © 2011 Springer-Verlag.

  2. Association Between Measures of Vertebral Endplate Morphology and Lumbar Intervertebral Disc Degeneration.

    Science.gov (United States)

    Duran, Semra; Cavusoglu, Mehtap; Hatipoglu, Hatice Gul; Sozmen Cılız, Deniz; Sakman, Bulent

    2017-05-01

    The aim of this study was to evaluate the association between vertebral endplate morphology and the degree of lumbar intervertebral disc degeneration via magnetic resonance imaging (MRI). In total, 150 patients who met the inclusion criteria and were 20-60 years of age were retrospectively evaluated. Patients were evaluated for the presence of intervertebral disc degeneration or herniation, and the degree of degeneration was assessed at all lumbar levels. Vertebral endplate morphology was evaluated based on the endplate sagittal diameter, endplate sagittal concave angle (ECA), and endplate sagittal concave depth (ECD) on sagittal MRI. The association between intervertebral disc degeneration or herniation and endplate morphological measurements was analysed. In MRI, superior endplates (ie, inferior endplates of the superior vertebra) were concave and inferior endplates (ie, superior endplates of the inferior vertebra) were flat at all disc levels. A decrease in ECD and an increase in ECA were detected at all lumbar levels as disc degeneration increased (P herniated lumbar discs (P lumbar disc degeneration or herniation and endplate sagittal diameter at lumbar intervertebral levels (P > .05). At all levels, ECD of women was significantly lesser than that of men and ECA of women was significantly greater than that of men (P lumbar intervertebral disc degeneration. Vertebral endplates at the degenerated disc level become flat; the severity of this flattening is correlated with the degree of disc degeneration. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  3. CT-guided percutaneous drainage within intervertebral space for pyogenic spondylodiscitis with psoas abscess

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Tomohiro; Morishita, Hiroyuki; Lida, Shigeharu; Asai, Shunsuke; Masui, Koji; Sato, Osamu (Department of Diagnostic Radiology, Japanese Red Cross Kyoto Daiichi Hospital, Kyoto (Japan)), Email: t-matsu@koto.kpu-m.ac.jp; Yamagami, Takuji; Nishimura, Tsunehiko (Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto (Japan)); Yamazoe, Shoichi (Department of Orthopedic Surgery, Japanese Red Cross Kyoto Daiichi Hospital, Kyoto (Japan))

    2012-02-15

    Background. Reports on CT-guided percutaneous drainage within the intervertebral space for pyogenic spondylodiscitis with a secondary psoas abscess are limited. Purpose. To evaluate CT-guided percutaneous drainage within the intervertebral space for pyogenic spondylodiscitis and a secondary psoas abscess in which the two sites appear to communicate. Material and Methods. Eight patients with pyogenic spondylodiscitis and a secondary psoas abscess showing communication with the intradiscal abscess underwent CT-guided percutaneous drainage within the intervertebral space. The clinical outcome was retrospectively assessed. Results. An 8-French pigtail catheter within the intervertebral space was successfully placed in all patients. Seven patients responded well to this treatment. The one remaining patient who had developed septic shock before the procedure died on the following day. The mean duration of drainage was 32 days (13-70 days). Only one patient with persistent back pain underwent surgery for stabilization of the spine after the improvement of inflammation. Among seven patients responding well, long-term follow-up (91-801 days, mean 292 days) was conducted in six patients excluding one patient who died of asphyxiation due to aspiration unrelated to the procedure within 30 days after the procedure. In these six patients, no recurrence of either pyogenic spondylodiscitis or the psoas abscess was noted. Conclusion. CT-guided percutaneous drainage within the intervertebral space can be effective for patients with pyogenic spondylodiscitis and a secondary psoas abscess if the psoas abscess communicates with the intradiscal abscess

  4. Measurement of lumbar spine intervertebral motion in the sagittal plane using videofluoroscopy.

    Science.gov (United States)

    Harvey, Steven; Hukins, David; Smith, Francis; Wardlaw, Douglas; Kader, Deiary

    2016-08-10

    Static radiographic techniques are unable to capture the wealth of kinematic information available from lumbar spine sagittal plane motion. Demonstration of a viable non-invasive technique for acquiring and quantifying intervertebral motion of the lumbar spine in the sagittal plane. Videofluoroscopic footage of sagittal plane lumbar spine flexion-extension in seven symptomatic volunteers (mean age = 48 yrs) and one asymptomatic volunteer (age = 54 yrs) was recorded. Vertebral bodies were digitised using customised software employing a novel vertebral digitisation scheme that was minimally affected by out-of-plane motion. Measurement errors in intervertebral rotation (± 1°) and intervertebral displacement (± 0.5 mm) compare favourably with the work of others. Some subjects presenting with an identical condition (disc prolapse) exhibited a similar column vertebral flexion-extension relative to S1 (L3: max. 5.9°, min. 5.6°), while in others (degenerative disc disease) there was paradoxically a significant variation in this measurement (L3: max. 28.1°, min. 0.7°). By means of a novel vertebral digitisation scheme and customised digitisation/analysis software, sagittal plane intervertebral motion data of the lumbar spine data has been successfully extracted from videofluoroscopic image sequences. Whilst the intervertebral motion signatures of subjects in this study differed significantly, the available sample size precluded the inference of any clinical trends.

  5. Current trends in biologics delivery to restore intervertebral disc anabolism.

    Science.gov (United States)

    Fontana, Gianluca; See, Eugene; Pandit, Abhay

    2015-04-01

    Low back pain is generally attributed to intervertebral disc (IVD) degeneration. This is a multifactorial disease induced by genetic and environmental factors and that progresses with aging. Disc degeneration is characterized by a limited ability of IVD cells to produce functional matrix while producing abnormal amounts of matrix-degrading enzymes. The prolonged imbalance between anabolism and catabolism in degenerative discs alters their composition and hydration. In turn, this results in increased angiogenesis and the loss of the disc's ability to maintain its aneural condition. Inflammation in the IVD, in particular the presence of pro-inflammatory cytokines, was found to favor innervation and also sensitization of the nociceptive pathways, thereby exacerbating degenerative symptoms. In this review, we discuss anti-inflammatory approaches to encounter disc catabolism, potential treatments to lower discogenic pain and pro-anabolic approaches in the form of protein delivery, gene therapy and cell delivery, to trigger regeneration in the IVD. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Lumbar artificial intervertebral disc replacement: a systematic review.

    Science.gov (United States)

    Thavaneswaran, Prema; Vandepeer, Meegan

    2014-03-01

    Low back pain represents a significant disease burden in Australia. Lumbar artificial intervertebral disc replacement (AIDR) has emerged as an alternative surgical option to lumbar fusion for patients suffering from axial low back pain as a result of degenerative disc disease. The aim of this review was to assess the safety and effectiveness of lumbar AIDR for patients suffering from significant axial back pain and/or radicular (nerve root) pain, secondary to disc degeneration or prolapse, who have failed non-operative treatment. A systematic search of several electronic databases was conducted between January 2005 and April 2012 to identify relevant randomized controlled trials and non-randomized comparative studies. Inclusion of studies was established through the application of a predetermined protocol by two independent reviewers. Six randomized controlled trials (comprising nine studies) and one non-randomized comparative study comparing lumbar AIDR with lumbar fusion were included in this review. For the majority of adverse events reported, there were no obvious differences in incidence rates between the two treatment groups, and serious adverse events were rare in both groups. Following lumbar AIDR, effectiveness outcomes including Oswestry Disability Index scores, procedural success rates, pain scores, narcotic medication use and patient satisfaction were generally significantly better than, or equivalent to, outcomes achieved following lumbar fusion. In the short to medium term, the safety and effectiveness of lumbar AIDR appears to be comparable to that of lumbar fusion. © 2013 Royal Australasian College of Surgeons.

  7. Obesity and recurrent intervertebral disc prolapse after lumbar microdiscectomy.

    Science.gov (United States)

    Quah, C; Syme, G; Swamy, G N; Nanjayan, S; Fowler, A; Calthorpe, D

    2014-03-01

    The primary aim of this study was to investigate the relationship between obesity and recurrent intervertebral disc prolapse (IDP) following lumbar microdiscectomy. A retrospective review of case notes from 2008 to 2012 was conducted for all patients who underwent single level lumbar microdiscectomy performed by a single surgeon. All patients were followed up at two weeks and six weeks following surgery, and given an open appointment for a further six months. A total of 283 patients were available for analysis: 190 (67%) were in the non-obese group and 93 (32.9%) in the obese group. There was no statistical difference in postoperative infection, dural tear or length of stay between the non-obese and obese groups. Recurrent symptomatic IDP was seen in 27 patients (9.5%) confirmed by magnetic resonance imaging. Nineteen (10.0%) were in the non-obese group and eight (8.6%) in the obese group (p>0.8). In our study, obesity was not a predictor of recurrent IDP following lumbar microdiscectomy. Our literature review confirmed that this study reports the largest series to date analysing the relationship between obesity and recurrent IDP following lumbar microdiscectomy in the British population.

  8. Analysis of trace element in intervertebral disc by Atomic Absorption Spectrometry techniques in degenerative disc disease in the Polish population

    Directory of Open Access Journals (Sweden)

    Andrzej Nowakowski

    2015-05-01

    This study is the first to our knowledge that profiles the elements in intervertebral disc in patients with degenerative changes. We have confirmed significant differences between the trace element contents in intervertebral disc and other tissue. It can be ground for further investigation.

  9. Simultaneity on the Rotating Disk

    Science.gov (United States)

    Koks, Don

    2017-04-01

    The disk that rotates in an inertial frame in special relativity has long been analysed by assuming a Lorentz contraction of its peripheral elements in that frame, which has produced widely varying views in the literature. We show that this assumption is unnecessary for a disk that corresponds to the simplest form of rotation in special relativity. After constructing such a disk and showing that observers at rest on it do not constitute a true rotating frame, we choose a "master" observer and calculate a set of disk coordinates and spacetime metric pertinent to that observer. We use this formalism to resolve the "circular twin paradox", then calculate the speed of light sent around the periphery as measured by the master observer, to show that this speed is a function of sent-direction and disk angle traversed. This result is consistent with the Sagnac Effect, but constitutes a finer analysis of that effect, which is normally expressed using an average speed for a full trip of the periphery. We also use the formalism to give a resolution of "Selleri's paradox".

  10. Blocking the Function of Inflammatory Cytokines and Mediators by Using IL-10 and TGF-β: A Potential Biological Immunotherapy for Intervertebral Disc Degeneration in a Beagle Model

    Directory of Open Access Journals (Sweden)

    Wei Li

    2014-09-01

    Full Text Available The debilitating effects of lower back pain are a major health issue worldwide. A variety of factors contribute to this, and oftentimes intervertebral disk degeneration (IDD is an underlying cause of this disorder. Inflammation contributes to IDD, and inflammatory cytokines such as tumor necrosis factor (TNF-α and interleukin (IL-1β, play key roles in the pathology of IDD. Therefore, the development of treatments that inhibit the expression and/or effects of TNF-α and IL-1β in IDD patients should be a promising therapeutic approach to consider. This study characterized the potential to suppress inflammatory cytokine production in degenerative intervertebral disc (NP cells by treatment with IL-10 and TGF-β in a canine model of IDD. IDD was induced surgically in six male beagles, and degenerative NP cells were isolated and cultured for in vitro studies on cytokine production. Cultured degenerative NP cells were divided into four experimental treatment groups: untreated control, IL-10-treated, TGF-β-treated, and IL-10- plus TGF-β-treated cells. Cultured normal NP cells served as a control group. TNF-α expression was evaluated by fluorescence activated cell sorting (FACS analysis and enzyme-linked immunosorbent assay (ELISA; moreover, ELISA and real-time PCR were also performed to evaluate the effect of IL-10 and TGF-β on NP cell cytokine expression in vitro. Our results demonstrated that IL-10 and TGF-β treatment suppressed the expression of IL-1β and TNF-α and inhibited the development of inflammatory responses. These data suggest that IL-10 and TGF-β should be evaluated as therapeutic approaches for the treatment of lower back pain mediated by IDD.

  11. Design Concepts of Polycarbonate-Based Intervertebral Lumbar Cages: Finite Element Analysis and Compression Testing

    Directory of Open Access Journals (Sweden)

    J. Obedt Figueroa-Cavazos

    2016-01-01

    Full Text Available This work explores the viability of 3D printed intervertebral lumbar cages based on biocompatible polycarbonate (PC-ISO® material. Several design concepts are proposed for the generation of patient-specific intervertebral lumbar cages. The 3D printed material achieved compressive yield strength of 55 MPa under a specific combination of manufacturing parameters. The literature recommends a reference load of 4,000 N for design of intervertebral lumbar cages. Under compression testing conditions, the proposed design concepts withstand between 7,500 and 10,000 N of load before showing yielding. Although some stress concentration regions were found during analysis, the overall viability of the proposed design concepts was validated.

  12. Acute pyogenic discitis in a degenerative intervertebral disc in an adult

    Directory of Open Access Journals (Sweden)

    Masamitsu Tanaka

    2010-08-01

    Full Text Available Masamitsu Tanaka1,2, Hiroshi Shimizu2, Yoshiyuki Yato1, Takashi Asazuma1, Koichi Nemoto11Department of Orthopedic Surgery, National Defense Medical College, Tokorozawa, Saitama; 2Department of Orthopedic Surgery, Self Defense Force Fukuoka Hospital, Kasuga, Fukuoka, JapanAbstract: A 35-year-old male who had been receiving conservative treatment for L4 isthmic spondylolisthesis suffered from pyogenic spondylodiscitis in the degenerative L4/L5 intervertebral disc space, which could be identified by comparison with previous images. Symptoms improved with conservative antibiotic treatment. Neovascularization may occur in the annulus fibrosus of a degenerative intervertebral disc, which may increase the risk of hematogenous infection, leading to “discitis” even in adults.Keywords: spondylodiscitis, spondylitis, discitis, isthmic spondylolisthesis, spondylolysis, intervertebral disc degeneration

  13. Spinning Disk Confocal System

    National Research Council Canada - National Science Library

    Schoenbach, Karl H

    2006-01-01

    ... of this proposal serving as Pi of the MURI. Experimental studies in which human cells were exposed to pulsed electric fields of up to 300 kV/cm amplitude, with durations as short as 10 ns, have confirmed that these pulses have strong effects...

  14. Dust in protoplanetary disks: observations*

    Directory of Open Access Journals (Sweden)

    Waters L.B.F.M.

    2015-01-01

    Full Text Available Solid particles, usually referred to as dust, are a crucial component of interstellar matter and of planet forming disks surrounding young stars. Despite the relatively small mass fraction of ≈1% (in the solar neighborhood of our galaxy; this number may differ substantially in other galaxies that interstellar grains represent of the total mass budget of interstellar matter, dust grains play an important role in the physics and chemistry of interstellar matter. This is because of the opacity dust grains at short (optical, UV wavelengths, and the surface they provide for chemical reactions. In addition, dust grains play a pivotal role in the planet formation process: in the core accretion model of planet formation, the growth of dust grains from the microscopic size range to large, cm-sized or larger grains is the first step in planet formation. Not only the grain size distribution is affected by planet formation. Chemical and physical processes alter the structure and chemical composition of dust grains as they enter the protoplanetary disk and move closer to the forming star. Therefore, a lot can be learned about the way stars and planets are formed by observations of dust in protoplanetary disks. Ideally, one would like to measure the dust mass, the grain size distribution, grain structure (porosity, fluffiness, the chemical composition, and all of these as a function of position in the disk. Fortunately, several observational diagnostics are available to derive constrains on these quantities. In combination with rapidly increasing quality of the data (spatial and spectral resolution, a lot of progress has been made in our understanding of dust evolution in protoplanetary disks. An excellent review of dust evolution in protoplanetary disks can be found in Testi et al. (2014.

  15. Tracing notochord-derived cells using a Noto-cre mouse: implications for intervertebral disc development

    Directory of Open Access Journals (Sweden)

    Matthew R. McCann

    2012-01-01

    Back pain related to intervertebral disc degeneration is the most common musculoskeletal problem, with a lifetime prevalence of 82%. The lack of effective treatment for this widespread problem is directly related to our limited understanding of disc development, maintenance and degeneration. The aim of this study was to determine the developmental origins of nucleus pulposus cells within the intervertebral disc using a novel notochord-specific Cre mouse. To trace the fate of notochordal cells within the intervertebral disc, we derived a notochord-specific Cre mouse line by targeting the homeobox gene Noto. Expression of this gene is restricted to the node and the posterior notochord during gastrulation [embryonic day 7.5 (E7.5-E12.5]. The Noto-cre mice were crossed with a conditional lacZ reporter for visualization of notochord fate in whole-mount embryos. We performed lineage-tracing experiments to examine the contribution of the notochord to spinal development from E12.5 through to skeletally mature mice (9 months. Fate mapping studies demonstrated that, following elongation and formation of the primitive axial skeleton, the notochord gives rise to the nucleus pulposus in fully formed intervertebral discs. Cellular localization of β-galactosidase (encoded by lacZ and cytokeratin-8 demonstrated that both notochordal cells and chondrocyte-like nucleus pulposus cells are derived from the embryonic notochord. These studies establish conclusively that notochordal cells act as embryonic precursors to all cells found within the nucleus pulposus of the mature intervertebral disc. This suggests that notochordal cells might serve as tissue-specific progenitor cells within the disc and establishes the Noto-cre mouse as a unique tool to interrogate the contribution of notochordal cells to both intervertebral disc development and disc degeneration.

  16. CT Fluoroscopy-Guided Transsacral Intervertebral Drainage for Pyogenic Spondylodiscitis at the Lumbosacral Junction

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Tomohiro, E-mail: t-matsu@tokai-u.jp; Mine, Takahiko, E-mail: mine@tsc.u-tokai.ac.jp; Hayashi, Toshihiko, E-mail: t.hayashi@tokai.ac.jp [Tokai University School of Medicine, Department of Radiology, Tokai University Hachioji Hospital (Japan); Kamono, Masahiro, E-mail: kamono@tsc.u-tokai.ac.jp; Taoda, Akiko, E-mail: acco@is.icc.u-tokai.ac.jp; Higaki, Megumu, E-mail: higaki@hachioji-hosp.tokai.ac.jp [Tokai University School of Medicine, Department of General Internal Medicine, Tokai University Hachioji Hospital (Japan); Hasebe, Terumitsu, E-mail: hasebe@tokai-u.jp [Tokai University School of Medicine, Department of Radiology, Tokai University Hachioji Hospital (Japan)

    2017-01-15

    PurposeTo retrospectively describe the feasibility and efficacy of CT fluoroscopy-guided transsacral intervertebral drainage for pyogenic spondylodiscitis at the lumbosacral junction with a combination of two interventional radiological techniques—CT-guided bone biopsy and abscess drainage.Materials and methodsThree patients with pyogenic spondylodiscitis at the lumbosacral junction were enrolled in this study between July 2013 and December 2015. The procedure of CT fluoroscopy-guided transsacral intervertebral drainage for pyogenic spondylodiscitis at the lumbosacral junction was as follows: the sacrum at S1 pedicle was penetrated with an 11-gauge (G) bone biopsy needle to create a path for an 8-French (F) pigtail drainage catheter. The bone biopsy needle was withdrawn, and an 18-G needle was inserted into the intervertebral space of the lumbosacral junction. Then, a 0.038-inch guidewire was inserted into the intervertebral space. Finally, the 8-F pigtail drainage catheter was inserted over the guidewire until its tip reached the intervertebral space. All patients received six-week antibiotics treatment.ResultsSuccessful placement of the drainage catheter was achieved for each patient without procedural complications. The duration of drainage was 17–33 days. For two patients, specific organisms were isolated; thus, definitive medical therapy was possible. All patients responded well to the treatment.ConclusionsCT fluoroscopy-guided transsacral intervertebral drainage for pyogenic spondylodiscitis at the lumbosacral junction is feasible and can be effective with a combination of two interventional techniques—CT fluoroscopy-guided bone biopsy and abscess drainage.

  17. Enhancing intervertebral disc repair and regeneration through biology: platelet-rich plasma as an alternative strategy

    Science.gov (United States)

    2013-01-01

    Intervertebral disc degeneration (IDD) is a common orthopedic disease associated with mechanical changes that may result in significant pain. Current treatments for IDD mainly depend on conservative therapies and spinal surgeries that are only able to relieve the symptoms but do not address the cause of the degeneration and even accelerate the degeneration of adjacent segments. This has prompted research to improve our understanding of the biology of intervertebral disc healing and into methods to enhance the regenerative process. Recently, biological therapies, including active substances, gene therapy and tissue engineering based on certain cells, have been attracting more attention in the field of intervertebral disc repair and regeneration. Early selection of suitable biological treatment is an ideal way to prevent or even reverse the progressive trend of IDD. Growth factors have been enjoying more popularity in the field of regeneration of IDD and many have been proved to be effective in reversing the degenerative trend of the intervertebral disc. Identification of these growth factors has led to strategies to deliver platelet-derived factors to the intervertebral disc for regeneration. Platelet-rich plasma (PRP) is the latest technique to be evaluated for promoting intervertebral disc healing. Activation of the PRP leads to the release of growth factors from the α-granules in the platelet cytoplasm. These growth factors have been associated with the initiation of a healing cascade that leads to cellular chemotaxis, angiogenesis, synthesis of collagen matrix, and cell proliferation. This review describes the current understanding of IDD and related biological therapeutic strategies, especially the promising prospects of PRP treatment. Future limitations and perspectives of PRP therapy for IDD are also discussed. PMID:24165687

  18. Biomechanical evaluation of a metal-on-metal cervical intervertebral disc prosthesis.

    Science.gov (United States)

    Colle, Kyle O; Butler, John B; Reyes, Phillip M; Newcomb, Anna G U S; Theodore, Nicholas; Crawford, Neil R

    2013-11-01

    In vitro nondestructive flexibility testing of the CerviCore total disc replacement (TDR) was performed. It was hypothesized that TDR would not significantly alter biomechanics relative to intact, whereas rigid fixation would cause significant changes. To assess the ability of a cervical metal-on-metal saddle-shaped TDR to replicate normal biomechanics in vitro. Human cadaveric flexibility experiment. Nine human cadaveric C3-T1 specimens were tested intact, after TDR and after anterior plating. Flexion, extension, lateral bending, and axial rotation were induced by pure moments; flexion-extension was then repeated using a simplified muscle force model with 70-N follower load. Optical markers measured three-dimensional intervertebral motion, and eight points of laminar surface strain were recorded near the left and right C5-C6 facet joints. Biomechanical parameters studied included range of motion (ROM), lax zone (LZ), angular coupling pattern, sagittal instantaneous axis of rotation (IAR), and facet loads normal to the facet joint plane. Mean values of parameters were compared statistically using repeated measures analysis of variance and Holm-Sidak tests. Total disc replacement caused significant reduction in ROM during extension (p=.004) and significant reduction in LZ during lateral bending (p=.01). However, plating significantly reduced both ROM and LZ during flexion, extension, and lateral bending (p.05) and 6.5 mm after plating (p>.05). Coupled axial rotation/degree lateral bending was 99% of intact after TDR but 76% of intact after plating (p=.15). Coupled lateral bending/degree axial rotation was 95% of intact after TDR but 85% of intact after plating (p=.43). Neither construct altered facet loads from intact. With regard to ROM, LZ, IAR, and coupling, deviations from intact biomechanics were less substantial after TDR than after plating. Facet load alterations were minimal with either construct. Our results show that this particular TDR permits ROM and

  19. Why Do Disks Form Jets?

    Science.gov (United States)

    Lynden-Bell, D.

    It is argued that jet modelers have given insufficient study to the natural magneto-static configurations of field wound up in the presence of a confining general pressure. Such fields form towers whose height grows with each twist at a velocity comparable to the circular velocity of the accretion disk that turns them. A discussion of the generation of such towers is preceded by a brief history of the idea that quasars, active galaxies, and galactic nuclei contain giant black holes with accretion disks.

  20. The Disk Mass Project: breaking the disk-halo degeneracy

    NARCIS (Netherlands)

    Verheijen, Marc A. W.; Bershady, Matthew A.; Swaters, Rob A.; Andersen, David R.; Westfall, Kyle B.; DE JONG, R. S.

    2007-01-01

    Little is known about the content and distribution of dark matter in spiral galaxies. To break the degeneracy in galaxy rotation curve decompositions, which allows a wide range of dark matter halo density profiles, an independent measure of the mass surface density of stellar disks is needed. Here,

  1. Genome-Wide Association Study in Dachshund: Identification of a Major Locus Affecting Intervertebral Disc Calcification

    DEFF Research Database (Denmark)

    Mogensen, Mette Sloth; Karlskov-Mortensen, Peter; Proschowsky, Helle Friis

    2011-01-01

    with intervertebral disc calcification in Dachshund through a genome-wide association (GWA) study. Based on thorough radiographic examinations, 48 cases with >= 6 disc calcifications or surgically treated for disc herniation and 46 controls with 0-1 disc calcifications were identified. GWA using the Illumina Canine......HD BeadChip identified a locus on chromosome 12 from 36.8 to 38.6 Mb with 36 markers reaching genome-wide significance (P-genome = 0.00001-0.026). This study suggests that a major locus on chromosome 12 harbors genetic variations affecting the development of intervertebral disc calcification in Dachshund....

  2. Standards of practice: quality assurance guidelines for percutaneous treatments of intervertebral discs.

    Science.gov (United States)

    Kelekis, Alexis D; Filippiadis, Dimitris K; Martin, Jean-Baptiste; Brountzos, Elias

    2010-10-01

    Percutaneous treatments are used in the therapy of small- to medium-sized hernias of intervertebral discs to reduce the intradiscal pressure in the nucleus and theoretically create space for the herniated fragment to implode inward, thus reducing pain and improving mobility and quality of life. These techniques involve the percutaneous removal of the nucleus pulposus by using a variety of chemical, thermal, or mechanical techniques and consist of removal of all or part of nucleus pulposus to induce more rapid healing of the abnormal lumbar disc. These guidelines are written to be used in quality improvement programs for assessing fluoroscopy- and/or computed tomography-guided percutaneous intervertebral disc ablative techniques.

  3. Wear assessments of a new cervical spinal disk prosthesis: Influence of loading and kinematic patterns during in vitro wear simulation.

    Science.gov (United States)

    Wu, Wenjie; Lyu, Jingtong; Liu, Hao; Rong, Xin; Wang, Beiyu; Hong, Ying; Gong, Quan; Li, Tao; Liu, Limin; Song, Yueming; Cai, Yong; Xu, Wenli

    2015-09-01

    Surgical treatment is one of the effective methods of treatment in cervical spondylosis. The traditional method of operation is decompression fusion; however, this surgery results in restricted movement of cervical vertebra and adjacent segment degeneration. Due to the deficiency of traditional surgery, scholars have widely carried out artificial cervical disk replacement surgery and have achieved good clinical effects. Comparing to the characteristics of the common artificial cervical disk which is used frequently, we developed a new artificial cervical intervertebral disk prosthesis. The purpose of this study was to determine the wear behavior in a cervical total disk replacement system. The total disk replacement system tested consists of a ultra-high-molecular-weight polyethylene inlay articulating between a Ti6Al4V alloy superior plate and an inferior plate, using a spine wear simulator, per the ISO 18192-1:2011 standard test methods. Three rotations and axial force were applied on each station. The specimens were removed at 5 × 10(5) and 10(6) cycles and at intervals of 10(6) cycles thereafter to determine the actual mass loss. The serum was replaced every 5 × 10(5) cycles. The specimens were changed periodically among the different stations. A mean ultrahigh molecular weight polyethylene inlay wear rate of 0.53 mg per million cycles (standard = 0.13 mg per 10(6) cycles) was found after 10(7) cycles. All inferior plates showed slight scratching after 10(7) cycles. The impingement wear simulation introduced here proved to be suitable to predict in vivo impingement behavior in regard to the contact pattern seen on retrieved devices of the Pretic-I disk arthroplasty design in a preclinical test. © IMechE 2015.

  4. Evaluation of intravertebral changes associated with the disk degeneration based on the MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Natoru [Dokkyo Univ. School of Medicine, Mibu, Tochigi (Japan)

    2000-03-01

    The magnetic resonance images (MRI) of 441 vertebral bodies of the 199 patients with intravertebral abnormality associated with adjacent disk degeneration were evaluated according to the Modic classification and a new geographic classification. They were also evaluated in relation with the various factors including disk space narrowing, vacuum phenomenon, disk herniation, Schmorl's node, ostephyte formation and spondylolisthesis. The new geographic classification is based on the three factors; depth of invasion: stage 1 (thin layer along the end-plate), stage 2 (less than a half of the vertebral height) and stage 3 (more than a half of the vertebral height), shape: end-plate type, Schmorl's node type, triangle type, meniscus type and band type, location: front type, center type, rear type, front and rear type and whole type. Only about a half of the vertebral bodies with intervertebral abnormality showed bilateral invasion adjacent to the degenerative disks on both sides and the superior edges were much more frequently involved than the inferior ones. There was relatively higher incidence (7%) of Modic Type I degeneration defined as high signal intensity (HSI) on T2 weighted spin-echo images (T2WI) and low signal intensity (LSI) on T1 weighted spin-echo images (T1WI) representing vascularized fibrous tissue than those previously reported. On the other hand there was relatively lower incidence (5%) of Modic Type II degeneration defined as high or iso intensity on T1WI and HSI on T2WI. Triangle front type was seen in almost a half of the vertebrae in stage 2 and stage 3, and the rest was divided into meniscus type and band type almost evenly. The end plate front type must be a precursor of the triangle front type. The Schmorl's node type was considered to be a precursor of the meniscus type as well as band type in some but many must stay in its form transformed to Type II degeneration. In general, the intravertebral abnormality may not be necessary to

  5. Effects of Training and Overtraining on Intervertebral Disc Proteoglycans.

    Science.gov (United States)

    Ueta, Renato H S; Tarini, Victor A F; Franciozi, Carlos E S; Tamaoki, Marcel J S; Medeiros, Valquíria P; Nader, Helena B; Faloppa, Flávio

    2018-01-01

    Animal experimental study. Evaluate the effect of physical activity and overtraining condition on glycosaminoglycan concentration on the intervertebral disc (IVD) using a rat running model. Some guidelines recommend the implementation of a physical exercise program as treatment for low back pain; however, cyclic loading impact on the health of the IVD and whether there is a dose-response relationship is still incompletely understood. Thirty-two rats ages 8 weeks were divided into four groups with eight animals each. The first 8 weeks were the adaptive phase, the overtraining phase was from the ninth to the eleventh week, which consisted of increasing the number of daily training sessions from 1 to 4 and the recovery phase was represented by the 12th and 13th weeks without training. Control group 1 (CG1) did not undergo any kind of training. Control group 2 (CG2) completed just the adaptive phase. Overtraining group 1 (OT1) completed the overtraining phase. Overtraining group 2 (OT2) completed the recovery phase. Running performance tests were used to assess the "overtraining" status of the animals. IVD glycosaminoglycans were extracted and quantified, and identified by electrophoresis. Glycosaminoglycans showed a distribution between chondroitin sulfate and dermatan sulfate. Glycosaminoglycans quantification showed decreasing concentration at the following order: OT1 > CG2 > OT2 > CG1. Increased expression of dermatan sulfate was verified at the groups submitted to any training. Overtraining condition, as assessed by muscle and cardiovascular endurance did not lessen glycosaminoglycan concentration in the IVD. In fact, physical exercise increased glycosaminoglycan concentration in the IVD in proportion to the training load, even at overtraining condition, returning to normal levels after the recovery phase and glycosaminoglycan production is a reversible acute positive response for mechanical stimulation of the IVD. N/A.

  6. Organ culture stability of the intervertebral disc: rat versus rabbit.

    Science.gov (United States)

    Seol, Dongrim; Choe, Hyeonghun; Ramakrishnan, Prem S; Jang, Keewoong; Kurriger, Gail L; Zheng, Hongjun; Lim, Tae-Hong; Martin, James A

    2013-06-01

    There is a need to develop mechanically active culture systems to better understand the role of mechanical stresses in intervertebral disc (IVD) degeneration. Motion segment cultures that preserve the native IVD structure and adjacent vertebral bodies are preferred as model systems, but rapid ex vivo tissue degeneration limits their usefulness. The stability of rat and rabbit IVDs is of particular interest, as their small size makes them otherwise suitable for motion segment culture. The goal of this study was to determine if there are substantial differences in the susceptibility of rat and rabbit IVDs to culture-induced degeneration. Lumbar IVD motion segments were harvested from young adult male Sprague-Dawley rats and New Zealand White rabbits and cultured under standard conditions for 14 days. Biochemical assays and safranin-O histology showed that while glycosaminoglycan (GAG) loss was minimal in rabbit IVDs, it was progressive and severe in rat IVDs. In the rat IVD, GAG loss was concomitant with the loss of notochordal cells and the migration of endplate (EP) cells into the nucleus pulposus (NP). None of these changes were evident in the rabbit IVDs. Compared to rabbit IVDs, rat IVDs also showed increased matrix metalloproteinase-3 (MMP-3) and sharply decreased collagen type I and II collagen expression. Together these data indicated that the rabbit IVD was dramatically more stable than the rat IVD, which showed culture-related degenerative changes. Based on these findings we conclude that the rabbit motion segments are a superior model for mechanobiologic studies. Copyright © 2013 Orthopaedic Research Society.

  7. Discectomy for primary and recurrent prolapse of lumbar intervertebral discs.

    Science.gov (United States)

    Ahsan, Kamrul; Najmus-Sakeb; Hossain, Alamgir; Khan, Shahidul Islam; Awwal, M A

    2012-04-01

    To reviewed 416 patients who underwent discectomy for primary or recurrent prolapse of lumbar intervertebral discs (PLID). Records of 296 men and 102 women aged 19 to 60 (mean, 39) years who underwent discectomy for a primary PLID, and 14 men and 4 women aged 28 to 50 (mean, 40) years who underwent revision discectomy for a recurrent ipsilateral (n=14) or contralateral (n=4) PLID at L4-5 (n=14), L5-S1 (n=3), or L3-4 (n=1) were reviewed. The pain-free interval, side and degree of herniation, operating time, length of hospital stay, and pre- and post-operative visual analogue score (VAS) for pain were recorded. Clinical outcomes were evaluated using the modified Macnab criteria and the Oswestry Disability Index. Patients were followed up for one to 4 years. The mean operating time was significantly longer in revision discectomy (65 vs. 141 minutes, p<0.001, unpaired t-test). There was no significant difference between revision and primary discectomy in terms of length of hospital stay or clinical improvement rates. Age, gender, smoking, profession, level and extent of herniation, and pain-free interval did not affect clinical outcomes. In the 18 revision cases, the mean pain-free interval until recurrence was 31 (range, 1-42) months. At the one-year follow-up, results were excellent in 8, good in 6, fair in 3, and poor in one. Three of the patients had persistent pain despite taking analgesics. 14 of the patients had returned to their normal daily activities. Complications included foot drop (n=1), dural tear (n=3), and superficial wound infection (n=1). Discectomy achieved satisfactory results for both primary and recurrent PLIDs.

  8. Disk Operating System User's Guide

    Science.gov (United States)

    1972-05-01

    This document serves the purpose of bringing together in one place most of the information a user needs to use the DDP-516 Disk Operating System, (DOS). DOS is a core resident, one user, console-oriented operating system which allows the user to cont...

  9. Three types of galaxy disks

    NARCIS (Netherlands)

    Pohlen, M.; Erwin, P.; Trujillo, I.; Beckman, J. E.; Knapen, JH; Mahoney, TJ; Vazdekis, A

    2008-01-01

    We present our new scheme for the classification of radial stellar surface brightness profiles for disk galaxies. We summarize the current theoretical attempts to understand their origin and give an example of an application by comparing local galaxies with their counterparts at high redshift (z

  10. Does a herniated nucleus pulposus contribute significantly to a decrease in height of the intervertebral disc? Quantitative volumetrich MRI

    Energy Technology Data Exchange (ETDEWEB)

    Holodny, A.I.; Kisza, P.S.; Contractor, S.; Liu, W.C. [Department of Radiology, UMDNJ-New Jersey Medical School, University Hospital C-320, 150 Bergen Street, Newark, NJ 07103-2714 (United States)

    2000-06-01

    A lumbar intervertebral disc with a herniated nucleus pulposus (HNP) often exhibits a decrease in the height of the intervertebral space. Our purpose was to ascertain whether the loss of volume of an HNP is sufficient to cause a perceptible decrease in the height of the intervertebral space. MRI of 44 patients with 51 HNPs were reviewed. The volumes of the herniated material and of the intervertebral discs were calculated for every level from L 1-2 to L 5-S 1. The average volume of the HNP was 503{+-}301 mm{sup 3}. The average volumes of all 220 intervertebral discs and of the 127 normal-appearing discs were 14442{+-}4200 mm{sup 3} and 17476{+-}2885 mm{sup 3} respectively. The average volume of the HNP represented 3.5% of the parent disc. An average HNP caused a decrease in intervertebral space height of 0.35 mm (0.56 pixels). Therefore, the loss of the volume of the HNP does not cause a significant decrease in the intervertebral space height. The average calculated decrease in the disc height is less than that reported in normal diurnal variation. (orig.)

  11. Optimization of the Processing of Mo Disks

    Energy Technology Data Exchange (ETDEWEB)

    Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, Dominique [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakhtang [Argonne National Lab. (ANL), Argonne, IL (United States); Harvey, James [NorthStar Medical Technologies, LLC, Madison, WI (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-01

    The objective of this work is to decrease the processing time for irradiated disks of enriched Mo for the production of 99Mo. Results are given for the dissolution of nonirradiated Mo disks, optimization of the process for large-scale dissolution of sintered disks, optimization of the removal of the main side products (Zr and Nb) from dissolved targets, and dissolution of irradiated Mo disks.

  12. Cadmium Removal Performances of Different Dye Ligands Attached Cryogel Disks

    Directory of Open Access Journals (Sweden)

    Burak Keleş

    2015-07-01

    Full Text Available Poly(HEMA cryogel disks were synthesized by free radical polymerization of 2-hydroxy-ethylmethacrylate (HEMA, and then Cibacron Blue F3GA (CB, Reactive Green 19 (RG and Congo Red (CR were immobilized as dye ligands. Disks were characterized by Fourier transform infrared spectroscopy (FTIR, scanning electron microscope (SEM and swelling degree, porosity calculations. Cd2+ adsorption experiments were performed for 60 min. Maximum adsorption capacities were determined as 25.5 mg/g; 48.0 mg/g and 28.5 mg/g at pH = 7.0 for poly(HEMA-CB; poly(HEMA-RG and poly(HEMA-CR, respectively. Langmuir isotherm fitted best with the adsorption data and adsorption thermodynamics showed that Cd2+ adsorption is thermodynamically favorable and a physisorption process. A great majority of adsorbed Cd2+ desorbed with 1 M NaCl and cryogel disks can be re-used in adsorption experiments. Cd2+ removal efficiencies of disks from human plasma are approximately 45 %. Dye-attached cryogel disks synthesized in this study have potential in use for environmental and therapeutic applications.

  13. The influence of slouching and lumbar support on iliolumbar ligaments, intervertebral discs and sacroiliac joints.

    Science.gov (United States)

    Snijders, Chris J; Hermans, Paul F G; Niesing, Ruud; Spoor, Cornelis W; Stoeckart, Rob

    2004-05-01

    To investigate lumbopelvic kinematics when moving into a slouch. A biomechanical model was developed. Load tests in vitro verified the model. The precise mechanism causing disc herniation and back sprain is still debated. Most biomechanical studies have focused on lifting in a stooped posture. Previous studies address instability situations due to Euler buckling of the spine under axial load. However, no studies address lumbosacral, iliolumbar and sacroiliac kinematics in slouching, i.e. flexing the spine in situations with negligible compressive spinal load. Modeling started with the click-clack movement, i.e. the transition from lumbar lordosis to lumbar kyphosis by the combination of backward rotation of the pelvis and ventral flexion of the spine. The flexed spine was compared with a crowbar which uses the iliolumbar ligaments as fulcrum and pivot. To analyse the click-clack movement in sitting, unembalmed erect human trunks were moved from a forward position to a backward position, recording angular changes between L5, sacrum and ilium. When moving the trunk stepwise backward with support at shoulder level, L5 showed forward rotation with respect to the sacrum, but rotation of the sacrum with respect to the iliac bones was reversed (i.e. counternutation). L5 showed displacement in ventral direction with respect to the ilium. Measurements were in agreement with prediction from the crowbar model of the spine. Backward rotation of the pelvis combined with flexion of the spine, i.e. slouching, results in backward rotation of the sacrum with respect to the ilium, dorsal widening of the intervertebral disc L5-S1 and strain on the iliolumbar ligaments when protection from back muscles against lumbar flexion is absent. Lumbar backrest support almost eliminates lumbosacral and sacroiliac movement. Understanding why the iliolumbar ligaments are loaded in slouching contributes to the understanding of the biomechanics of low back pain in everyday situations with small or

  14. Biomechanical and Endplate Effects on Nutrient Transport in the Intervertebral Disc.

    Science.gov (United States)

    Giers, Morgan B; Munter, Bryce T; Eyster, Kyle J; Ide, George D; Newcomb, Anna G U S; Lehrman, Jennifer N; Belykh, Evgenii; Byvaltsev, Vadim A; Kelly, Brian P; Preul, Mark C; Theodore, Nicholas

    2017-03-01

    Physical data are lacking on nutrient transport in human intervertebral discs (IVDs), which support regeneration. Our objective was to study nutrient transport in porcine IVDs to determine the effects of biomechanical and physiological factors. In vitro testing of whole porcine IVDs was performed under different loading conditions. Fifty cervical, thoracic, and lumbar discs with attached end plates were removed from 4 Yorkshire pigs (90-150 lbs). Discs were placed in Safranin O or Fast Green FCF histological stains in diffusion or diurnal compression-tested groups. The end plate was studied by the use of polyurethane to block it. Traction was studied with a mechanical testing frame. Discs were cut transversely and photographed. Images were analyzed for depth of annulus fibrosus (AF) stained. The nucleus pulposus (NP) was assigned a staining score. Results showed no difference in AF staining between the 2 stains (P = 0.60). The depth of AF staining did not increase (P = 0.60) due to convection or disc height change via diurnal loading. The NP in all open end plate samples was stained completely by day 3. NP staining was decreased in blocked end plate samples (P = 0.07) and AF staining was significantly less in traction samples than in diffusion-only samples (P = 0.04). This method showed that most small molecule nutrient transport occurs via the end plate. Compressive load was a negligible benefit or hindrance to transport. Traction hindered transport in the short term. This method can be used to study strategies for increasing nutrient transport in IVDs. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Growing and moving planets in disks

    NARCIS (Netherlands)

    Paardekooper, Sijme-Jan

    2006-01-01

    Planets form in disks that are commonly found around young stars. The intimate relationship that exists between planet and disk can account for a lot of the exotic extrasolar planetary systems known today. In this thesis we explore disk-planet interaction using numerical hydrodynamical simulations.

  16. Basics of Videodisc and Optical Disk Technology.

    Science.gov (United States)

    Paris, Judith

    1983-01-01

    Outlines basic videodisc and optical disk technology describing both optical and capacitance videodisc technology. Optical disk technology is defined as a mass digital image and data storage device and briefly compared with other information storage media including magnetic tape and microforms. The future of videodisc and optical disk is…

  17. Microporous Carbon Disks For Sorption Refrigerators

    Science.gov (United States)

    Munukutla, Lakshmi V.; Moore, Mark R.

    1993-01-01

    Slow, carefully controlled pyrolysis found to turn polyvinylidene chloride disks into carbon disks having small pores and large surface areas. Disks exhibit high adsorptivities making them useful in krypton-sorption refrigerators. Carbons made from polyvinylidene chloride have greater adsorptive capacities. Thermal instability controlled and variability of product reduced by careful control of rates of heating, heating times, and rate of final cooling.

  18. Experimental model of intervertebral disc degeneration by needle puncture in Wistar rats

    Energy Technology Data Exchange (ETDEWEB)

    Issy, A.C.; Castania, V.; Castania, M. [Departamento de Morfologia, Fisiologia e Patologia Básica, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Salmon, C.E.G. [Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Nogueira-Barbosa, M.H. [Divisão de Radiologia, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Bel, E. Del [Departamento de Morfologia, Fisiologia e Patologia Básica, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Defino, H.L.A. [Departamento de Biomecânica, Medicina e Reabilitação do Sistema Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2013-03-15

    Animal models of intervertebral disc degeneration play an important role in clarifying the physiopathological mechanisms and testing novel therapeutic strategies. The objective of the present study is to describe a simple animal model of disc degeneration involving Wistar rats to be used for research studies. Disc degeneration was confirmed and classified by radiography, magnetic resonance and histological evaluation. Adult male Wistar rats were anesthetized and submitted to percutaneous disc puncture with a 20-gauge needle on levels 6-7 and 8-9 of the coccygeal vertebrae. The needle was inserted into the discs guided by fluoroscopy and its tip was positioned crossing the nucleus pulposus up to the contralateral annulus fibrosus, rotated 360° twice, and held for 30 s. To grade the severity of intervertebral disc degeneration, we measured the intervertebral disc height from radiographic images 7 and 30 days after the injury, and the signal intensity T2-weighted magnetic resonance imaging. Histological analysis was performed with hematoxylin-eosin and collagen fiber orientation using picrosirius red staining and polarized light microscopy. Imaging and histological score analyses revealed significant disc degeneration both 7 and 30 days after the lesion, without deaths or systemic complications. Interobserver histological evaluation showed significant agreement. There was a significant positive correlation between histological score and intervertebral disc height 7 and 30 days after the lesion. We conclude that the tail disc puncture method using Wistar rats is a simple, cost-effective and reproducible model for inducing disc degeneration.

  19. Piperine mediates LPS induced inflammatory and catabolic effects in rat intervertebral disc.

    Science.gov (United States)

    Li, Yan; Li, Kang; Hu, Yiqin; Xu, Bo; Zhao, Jie

    2015-01-01

    Piperine is an exact of the active phenolic component from Black pepper. It has been reported to have many biological activities including anti-oxidant, anti-inflammatory and anti-tumor effects. Intervertebral disc degeneration (IDD) is a degenerative disease closely relate to inflammation of nucleus pulposus (NP) cells. This study aimed to assess the anti-inflammatory and anti-catabolic effects of piperine in rat intervertebral disc using in vitro and ex vivo analyzes. We demonstrated that piperine could inhibit LPS induced expression and production of inflammatory factors and catabolic proteases in NP cells culture model. It significantly inhibited multiple inflammatory factors and oxidative stress-associated genes (IL-1β, TNF-α, IL-6, iNOS), MMPs (MMP-3, MMP-13), ADAMTS (ADAMTS-4, ADAMTS-5) mRNA expression and NO production in a concentration-dependent manner. Moreover, piperine could reverse the LPS-induced inhibition of gene expression of aggrecan and collagen-II. Histologic and dimethylmethylene blue analysis indicated piperine could also against LPS induced proteoglycan (PG) depletion in a rat intervertebral disc culture model. Western blot results showed that piperine inhibited the LPS-mediated phosphorylation of JNK and activation of NF-κB. Finally, our results demonstrated the ability of piperine to antagonize LPS-mediated inflammation of NP cells and suppression of PG in rat intervertebral disc, suggesting a potential agent for treatment of IDD in future.

  20. Clinical effects of acupuncture after surgical operation in patients with prolapse of the lumbar intervertebral disc.

    Science.gov (United States)

    Zhao, Bin-xiu; Wang, Kun-zheng; Zhao, Jie-Xiu; Wang, Chun-sheng; Huang, Xiang-hui; Shu-qiang, Ma; Qiang, Hui

    2008-12-01

    To investigate the clinical effects of acupuncture after surgical operation in patients with prolapse of the lumbar intervertebral disc (PLID). Sixty-nine patients in this series, who had undergone the removal of nucleus pulposus and the intervertebral fusion as well, were randomly divided into a treatment group of 35 cases and a control group of 34 cases. The former was treated by acupuncture and conventional rehabilitation therapy, and the latter only by the rehabilitation therapy. The therapeutic effects were evaluated according to the scoring system stipulated by Japanese Orthopedics Association (JOA). In the treatment group, the average functional recovery rates in 3-month, 6-month and one-year periods were respectively 49.93%, 90.31% and 95.08%; while the rates were repesctively 26.24%, 63.42% and 71.36% in the control group, showing statistically significant difference between the two groups (Pprolapse of the lumbar intervertebral disc after surgical removal of nucleus pulposus and with intervertebral fusion.

  1. Quantitative analysis of changes in cervical intervertebral foramen size with vertebral translation.

    Science.gov (United States)

    Ebraheim, Nabil A; Liu, Jiayong; Shafiq, Qaiser; Lu, Jike; Pataparla, Sravanthy; Yeasting, Richard A; Woldenberg, Lee

    2006-02-01

    Simulated translation of the C5 vertebra was performed in 20 embalmed cadaveric cervical spines, and cross-sectional areas of the C4-C5 and C5-C6 intervertebral foramina were measured and compared before and after translation of the C5 vertebra. To determine the relationship of cross-sectional intervertebral foraminal areas to the degrees of vertebral translation. The common feature of clinical instability and adjacent diseases of the cervical spine is malalignment of the cervical spine (i.e., there is ventral and dorsal translation of vertebral body with respect to the adjacent upper and lower vertebral body, respectively). To our knowledge, no previous study has analyzed the quantitative effect of vertebral translation on the size of the intervertebral foramina. The cross-sectional areas of the intervertebral foramina at C4-C5 and C5-C6 were measured on computerized tomography. The images were then transferred to the personal computer, where consecutive dorsal translations of C5 vertebrae with a 1-mm increment from 1 to 5-mm displacements were performed using Microsoft paint software (Microsoft, Corp., Redmond, WA). National Institutes of Health (Bethesda, MD) Image J software (V1.33m) was then used to measure the areas of both sides of C4-C5 and C4-C6 foramina at normal and each displacement level in the computer. Following dorsal translation of C5 vertebra, anterolisthesis of C4 relative to C5 and retrolisthesis of C5 relative to C6 was noted. No significant difference was found between the measured values using Aquarius Image software (Microsoft, Corp.) on computerized tomography and National Institutes of Health image J software on the desktop computer (P > 0.05). When compared with normal values, there was an increase in the C4-C5 intervertebral foraminal area (i.e., 6%, 14%, 18%, 21%, and 26% with anterolisthesis of C4 relative to C5 following 1, 2, 3, 4, and 5-mm dorsal translation of the C5 vertebra, respectively). There was a 12% decrease in the C5-C6

  2. Intervertebral disc (IVD): Structure, degeneration, repair and regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Whatley, Benjamin R.; Wen Xuejun, E-mail: xjwen@clemson.edu

    2012-02-01

    Low back pain affects a large portion of the population, resulting in high care costs for therapy and treatment. One primary cause of low back pain is the degeneration of the intervertebral disc (IVD) resulting in the compression of the spinal nerves and adjacent vertebrae. Exact causes of degeneration are unknown, but it is thought that natural aging, and both biological and genetic factors may play a significant role in the degenerative process. Conventional methods to alleviate low back pain include spinal fusion and artificial disc replacement. Traditional treatments through spinal fusion may eliminate pain yet do not restore disc function and lead to further degeneration of adjacent levels by altering disc biomechanics and natural kinematics. Recently, artificial IVD replacements have started to gain interest, with two IVD implants currently approved in the United States. Although these implants facilitate the preservation of motions and disc space height, they are unable to sustain compressive forces due to their lack of elasticity. In addition, the implants may produce wear debris that can cause osteolysis and other deleterious effects. As an alternative to these conventional approaches, tissue engineered IVD constructs offer the advantage of biointegration while preserving the essential attributes of natural motion and disc space restoration. There is a great need for the development of tissue engineered scaffolds that simulate the natural 3D morphology and microenvironment of the targeted tissue. Scaffolds should facilitate biological transport to satisfy nutrition and waste removal requirements within the IVD. The discrete tissue architectures of the nucleus pulposus (NP) and annulus fibrosus (AF) have posed great challenges to IVD tissue engineering. Current attempts have not been able to satisfy the biological functions and/or mechanical properties of native tissue. Therefore, these current scaffolds are far from satisfactory. This review highlights the

  3. * In Vitro Generated Intervertebral Discs: Toward Engineering Tissue Integration.

    Science.gov (United States)

    Iu, Jonathan; Massicotte, Eric; Li, Shu-Qiu; Hurtig, Mark B; Toyserkani, Ehsan; Santerre, J Paul; Kandel, Rita A

    2017-09-01

    The intervertebral disc (IVD) is composed of nucleus pulposus (NP) surrounded by multilamellated annulus fibrosus (AF), and is located between the vertebral bodies. Current treatments for chronic neck or low back pain do not completely restore the functionality of degenerated IVDs. Thus, developing biological disc replacements is an approach of great interest. Given the complex structure of the IVD, tissue engineering of the individual IVD components and then combining them together may be the only way to achieve this. The engineered disc must then be able to integrate into the host spine to ensure mechanical stability. The goal of this study was to generate an integrated model of an IVD in vitro. Multilamellated AF tissues were generated in vitro using aligned nanofibrous polycarbonate urethane scaffolds and AF cells. After 3 weeks in culture, it was placed around NP tissue formed on and integrated with a porous bone substitute material (calcium polyphosphate). The two tissues were cocultured to fabricate the IVD model. The AF tissue composed of six lamellae containing type I collagen-rich extracellular matrix (ECM) and the NP tissue had type II collagen- and aggrecan-rich ECM. Immunofluorescence studies showed both type I and II collagen at the AF-NP interface. There was evidence of integration of the tissues. The peel test for AF lamellae showed an interlamellar shear stress of 0.03 N/mm. The AF and NP were integrated as the pushout test demonstrated that the AF-NP interface had significantly increased mechanical stability by 2 weeks of coculture. To evaluate if these tissues remained integrated, allogeneic IVD model constructs were implanted into defects freshly made in the NP-inner AF and bone of the bovine coccygeal spine. One month postimplantation, the interfaces between the AF lamellae remained intact and there was integration with the host AF tissue. No inflammatory reaction was noted at this time period. In summary, an engineered IVD implant with

  4. Evaluation of the intervertebral neck injury criterion using simulated rear impacts.

    Science.gov (United States)

    Panjabi, Manohar M; Ito, Shigeki; Ivancic, Paul C; Rubin, Wolfgang

    2005-08-01

    The Intervertebral Neck Injury Criterion (IV-NIC) is based on the hypothesis that intervertebral motion beyond the physiological limit may injure spinal soft tissues during whiplash, while the Neck Injury Criterion (NIC) hypothesizes that sudden changes in spinal fluid pressure may cause neural injury. Goals of the present study, using a biofidelic whole cervical spine model with muscle force replication, were to correlate IV-NIC with soft-tissue injury, determine the IV-NIC injury threshold, and compare IV-NIC and NIC. Using a bench-top apparatus, rear-impacts were simulated at 3.5, 5, 6.5, and 8 g horizontal accelerations of the T1 vertebra. Pre- and post-whiplash flexibility tests measured the soft tissue injury threshold, i.e. significant increases in the intervertebral neutral zone (NZ) or range of motion (ROM) above corresponding baseline values. Extension IV-NIC peaks correlated well with NZ and ROM increases at C0-C1 and at C3-C4 through C7-T1 (r=0.64 and 0.62 respectively, pNIC injury thresholds (95% confidence limits) varied among the intervertebral levels and ranged between 1.5 (1.1, 1.9) at C5-C6 and 3.4 (2.4, 4.4) at C7-T1. The NIC injury threshold was 8.7 (7.7, 9.7) m2/s2, substantially less than the proposed threshold of 15 m2/s2. Results support the use of IV-NIC for determining the cervical spine injury threshold and injury severity. Advantages of IV-NIC include the ability to predict the intervertebral level, mode, severity, and time of the cervical spine soft-tissue injury.

  5. Small vertebral cross-sectional area and tall intervertebral disc in adolescent idiopathic scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Ponrartana, Skorn; Fisher, Carissa L.; Aggabao, Patricia C. [Keck School of Medicine, University of Southern California, Department of Radiology, Children' s Hospital Los Angeles, Los Angeles, CA (United States); Chavez, Thomas A. [Keck School of Medicine, University of Southern California, Department of Pediatrics, Children' s Hospital Los Angeles, Los Angeles, CA (United States); Broom, Alexander M.; Wren, Tishya A.L.; Skaggs, David L. [Keck School of Medicine, University of Southern California, Department of Orthopaedic Surgery, Children' s Hospital Los Angeles, Los Angeles, CA (United States); Gilsanz, Vicente [Keck School of Medicine, University of Southern California, Department of Radiology, Children' s Hospital Los Angeles, Los Angeles, CA (United States); Keck School of Medicine, University of Southern California, Department of Pediatrics, Children' s Hospital Los Angeles, Los Angeles, CA (United States); Keck School of Medicine, University of Southern California, Department of Orthopaedic Surgery, Children' s Hospital Los Angeles, Los Angeles, CA (United States)

    2016-09-15

    When compared to boys, girls have smaller vertebral cross-sectional area, which conveys a greater spinal flexibility, and a higher prevalence of adolescent idiopathic scoliosis. To test the hypothesis that small vertebral cross-sectional area and tall intervertebral disc height are structural characteristics of patients with adolescent idiopathic scoliosis. Using multiplanar imaging techniques, measures of vertebral cross-sectional area, vertebral height and intervertebral disc height in the lumbar spine were obtained in 35 pairs of girls and 11 pairs of boys with and without adolescent idiopathic scoliosis of the thoracic spine matched for age, height and weight. Compared to adolescents without spinal deformity, girls and boys with adolescent idiopathic scoliosis had, on average, 9.8% (6.68 ± 0.81 vs. 7.40 ± 0.99 cm{sup 2}; P = 0.0007) and 13.9% (8.22 ± 0.84 vs. 9.55 ± 1.61 cm{sup 2}; P = 0.009) smaller vertebral cross-sectional dimensions, respectively. Additionally, patients with adolescent idiopathic scoliosis had significantly greater values for intervertebral disc heights (9.06 ± 0.85 vs. 7.31 ± 0.62 mm and 9.09 ± 0.87 vs. 7.61 ± 1.00 mm for girls and boys respectively; both P ≤ 0.011). Multiple regression analysis indicated that the presence of scoliosis was negatively associated with vertebral cross-sectional area and positively with intervertebral disc height, independent of sex, age and body mass index. We provide new evidence that girls and boys with adolescent idiopathic scoliosis have significantly smaller vertebral cross-sectional area and taller intervertebral disc heights - two major structural determinants that influence trunk flexibility. With appropriate validation, these findings may have implications for the identification of children at the highest risk for developing scoliosis. (orig.)

  6. A Pulsar and a Disk

    Science.gov (United States)

    Kohler, Susanna

    2016-07-01

    Recent, unusual X-ray observations from our galactic neighbor, the Small Magellanic Cloud, have led to an interesting model for SXP 214, a pulsar in a binary star system.Artists illustration of the magnetic field lines of a pulsar, a highly magnetized, rotating neutron star. [NASA]An Intriguing BinaryAn X-ray pulsar is a magnetized, rotating neutron star in a binary system with a stellar companion. Material is fed from the companion onto the neutron star, channeled by the objects magnetic fields onto a hotspot thats millions of degrees. This hotspot rotating past our line of sight is what produces the pulsations that we observe from X-ray pulsars.Located in the Small Magellanic Cloud, SXP 214 is a transient X-ray pulsar in a binary with a Be-type star. This star is spinning so quickly that material is thrown off of it to form a circumstellar disk.Recently, a team of authors led by JaeSub Hong (Harvard-Smithsonian Center for Astrophysics) have presented new Chandra X-ray observations of SXP 214, tracking it for 50 ks (~14 hours) in January 2013. These observations reveal some very unexpected behavior for this pulsar.X-ray PuzzleThe energy distribution of the X-ray emission from SXP 214 over time. Dark shades or blue colors indicate high counts, and light shades or yellow colors indicate low counts. Lower-energy X-ray emission appeared only later, after about 20 ks. [Hong et al. 2016]Three interesting pieces of information came from the Chandra observations:SXP 214s rotation period was measured to be 211.5 s an increase in the spin rate since the discovery measurement of a 214-second period. Pulsars usually spin down as they lose angular momentum over time so what caused this one to spin up?Its overall X-ray luminosity steadily increased over the 50 ks of observations.Its spectrum became gradually softer (lower energy) over time; in the first 20 ks, the spectrum only consisted of hard X-ray photons above 3 keV, but after 20 ks, softer X-ray photons below 2 ke

  7. Separate the Sheep from the Goats: Use and Limitations of Large Animal Models in Intervertebral Disc Research.

    Science.gov (United States)

    Reitmaier, Sandra; Graichen, Friedmar; Shirazi-Adl, Aboulfazl; Schmidt, Hendrik

    2017-10-04

    Approximately 5,168 large animals (pigs, sheep, goats, and cattle) were used for intervertebral disc research in identified studies published between 1985 and 2016. Most of the reviewed studies revealed a low scientific impact, a lack of sound justifications for the animal models, and a number of deficiencies in the documentation of the animal experimentation. The scientific community should take suitable measures to investigate the presumption that animal models have translational value in intervertebral disc research. Recommendations for future investigations are provided to improve the quality, validity, and usefulness of animal studies for intervertebral disc research. More in vivo studies are warranted to comprehensively evaluate the suitability of animal models in various applications and help place animal models as an integral, complementary part of intervertebral disc research.

  8. Perceptions and use of passive intervertebral motion assessment of the spine: a survey among physiotherapists specializing in manual therapy.

    NARCIS (Netherlands)

    Trijffel, E. van; Oostendorp, R.A.B.; Lindeboom, R.; Bossuyt, P.M.; Lucas, C.

    2009-01-01

    Manual therapists commonly use passive intervertebral motion (PIVM) assessment within physical examination. Data describing the use and interpretation of this manual diagnostic procedure, as well as therapists' perception of related importance and confidence, are lacking. A survey was conducted

  9. Study of the influence of degenerative intervertebral disc changes on the deformation behavior of the cervical spine segment in flexion

    Science.gov (United States)

    Kolmakova, Tatyana V.

    2016-11-01

    The paper describes the model of the cervical spine segment (C3-C4) and the calculation results of the deformation behavior of the segment under degenerative changes of the intervertebral disc. The segment model was built based on the experimental literature data taking into account the presence of the cortical and cancellous bone tissue of vertebral bodies. The calculation results show that degenerative changes of the intervertebral disc cause the immobility of the C3 vertebra at flexion.

  10. Characterization of the age-dependent intervertebral disc changes in rabbit by correlation between MRI, histology and gene expression

    OpenAIRE

    Gauthier Olivier; Fellah Borhane H; Lesoeur Julie; Masson Martial; Grimandi Gaël; Pot-Vaucel Marianne; Clouet Johann; Fusellier Marion; Cherel Yan; Maugars Yves; Guicheux Jérôme; Vinatier Claire

    2011-01-01

    Abstract Background The present study was conducted to address whether the intervertebral disc of rabbit could be considered (i) as a valuable model to provide new insights into the tissue and cellular changes of Nucleus pulposus aging and (ii) as an appropriate tool to investigate the efficacy of Nucleus pulposus cell-based biotherapies. Methods Lumbar intervertebral disc from rabbits with increasing ages (1, 6 and 30 month-old) were compared by MRI and histological observation using Pfirrma...

  11. The Effect of Intervertebral Cartilage on Neutral Posture and Range of Motion in the Necks of Sauropod Dinosaurs

    OpenAIRE

    Taylor, Michael P.; Mathew J Wedel

    2013-01-01

    The necks of sauropod dinosaurs were a key factor in their evolution. The habitual posture and range of motion of these necks has been controversial, and computer-aided studies have argued for an obligatory sub-horizontal pose. However, such studies are compromised by their failure to take into account the important role of intervertebral cartilage. This cartilage takes very different forms in different animals. Mammals and crocodilians have intervertebral discs, while birds have synovial joi...

  12. Foundations of Black Hole Accretion Disk Theory.

    Science.gov (United States)

    Abramowicz, Marek A; Fragile, P Chris

    2013-01-01

    This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion disks might reveal some of the unique signatures of strong gravity: the event horizon, the innermost stable circular orbit, and the ergosphere. We then review, from a first-principles perspective, the physical processes at play in accretion disks. This leads us to the four primary accretion disk models that we review: Polish doughnuts (thick disks), Shakura-Sunyaev (thin) disks, slim disks, and advection-dominated accretion flows (ADAFs). After presenting the models we discuss issues of stability, oscillations, and jets. Following our review of the analytic work, we take a parallel approach in reviewing numerical studies of black hole accretion disks. We finish with a few select applications that highlight particular astrophysical applications: measurements of black hole mass and spin, black hole vs. neutron star accretion disks, black hole accretion disk spectral states, and quasi-periodic oscillations (QPOs).

  13. Foundations of Black Hole Accretion Disk Theory

    Directory of Open Access Journals (Sweden)

    Marek A. Abramowicz

    2013-01-01

    Full Text Available This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion disks might reveal some of the unique signatures of strong gravity: the event horizon, the innermost stable circular orbit, and the ergosphere. We then review, from a first-principles perspective, the physical processes at play in accretion disks. This leads us to the four primary accretion disk models that we review: Polish doughnuts (thick disks, Shakura-Sunyaev (thin disks, slim disks, and advection-dominated accretion flows (ADAFs. After presenting the models we discuss issues of stability, oscillations, and jets. Following our review of the analytic work, we take a parallel approach in reviewing numerical studies of black hole accretion disks. We finish with a few select applications that highlight particular astrophysical applications: measurements of black hole mass and spin, black hole vs. neutron star accretion disks, black hole accretion disk spectral states, and quasi-periodic oscillations (QPOs.

  14. Thoracic mobilisation and periscapular soft tissue manipulations in the management of chronic Prolapsed Intervertebral Disc (PIVD - An innovative manual therapy approach

    Directory of Open Access Journals (Sweden)

    Raj Kiran

    2017-10-01

    Full Text Available Background The most common cause of CLBP is discogenic lower back pain. Researches haveshown that connective tissue remodelling occurs in CLBP and thoracic spinal mobility and thoracolumbar mobility have higher correlations with LBP. Aims To see the effect of upper back fascia and periscapular muscles stretching and thoracic mobilisation to reduce symptoms in subjects with CLBP due to lumbar disk herniation. Methods A total of 40 subjects with CLBP due to Prolapsed Intervertebral Disc (PIVD were recruited and randomly distributed in two groups. Group 1 was given stretching of upper back fascia and periscapular muscles and thoracic mobilization along with conventional exercises (Cyriax listing correction -I followed by repeated McKenzie back extension exercise and Core muscle strengthening. Group 2 received only conventional exercises. Outcome Measures: visual analog scale, Oswestry Disability Index and Modified Schober's Test. Measurements were taken before and after three weeks of treatment, for five days/week. Results Overall results of the study, both Group 1 and Group 2 showed improvement in pain, function and lumbar Range of Motion (ROM after three weeks of intervention. However, Group 1 improved significantly to a greater extent in pain, ROM and function than the Group 2. Conclusion Stretching of periscapular muscles and fascia of the upper back and mobilisation of upper thoracic spine is found to be effective for the management of chronic low back pain due to PIVD.

  15. Secular Evolution in Disk Galaxies

    Science.gov (United States)

    Kormendy, John

    2013-10-01

    Self-gravitating systems evolve toward the most tightly bound configuration that is reachable via the evolution processes that are available to them. They do this by spreading -- the inner parts shrink while the outer parts expand -- provided that some physical process efficiently transports energy or angular momentum outward. The reason is that self-gravitating systems have negative specific heats. As a result, the evolution of stars, star clusters, protostellar and protoplanetary disks, black hole accretion disks and galaxy disks are fundamentally similar. How evolution proceeds then depends on the evolution processes that are available to each kind of self-gravitating system. These processes and their consequences for galaxy disks are the subjects of my lectures and of this Canary Islands Winter School. I begin with a review of the formation, growth and death of bars. Then I review the slow (`secular') rearrangement of energy, angular momentum, and mass that results from interactions between stars or gas clouds and collective phenomena such as bars, oval disks, spiral structure and triaxial dark haloes. The `existence-proof' phase of this work is largely over: we have a good heuristic understanding of how nonaxisymmetric structures rearrange disk gas into outer rings, inner rings and stuff dumped onto the centre. The results of simulations correspond closely to the morphology of barred and oval galaxies. Gas that is transported to small radii reaches high densities. Observations confirm that many barred and oval galaxies have dense central concentrations of gas and star formation. The result is to grow, on timescales of a few Gyr, dense central components that are frequently mistaken for classical (elliptical-galaxy-like) bulges but that were grown slowly out of the disk (not made rapidly by major mergers). The resulting picture of secular galaxy evolution accounts for the richness observed in galaxy structure. We can distinguish between classical and pseudo

  16. Extraforaminal ligament attachments of human lumbar nerves.

    Science.gov (United States)

    Kraan, G A; Delwel, E J; Hoogland, P V J M; van der Veen, M R; Wuisman, P I J M; Stoeckart, R; Kleinrensink, G J; Snijders, C J

    2005-03-15

    An anatomic study of the extraforaminal attachments of the lumbar spinal nerves was performed using human lumbar spinal columns. To identify and describe the existence of ligamentous structures at each lumbar level that attach lumbar spinal nerves to structures at the level of the extraforaminal region. During the last 120 years, several mechanisms to protect the spinal nerve against traction have been described. All these structures involved are located in the spinal canal, proximal to the intervertebral foramen. Five embalmed human lumbar spines (T12-S1) were used. Bilaterally, the extraforaminal region was dissected to describe and measure anatomic structures and their relationships. Histology was performed with staining on the sites of attachment and along the ligament. The levels T12-L2 show bilaterally 2 ligaments, a superior extraforaminal ligament and an inferior extraforaminal ligament. The superior extraforaminal ligament emerges from the joint capsule of the facet joints and inserts in both, the intervertebral disc and the ventral crista of the intervertebral foramen, passing the spinal nerve laterally. In one specimen on level L2-L3, the superior extraforaminal ligament is not attached to the spinal nerve. The inferior extraforaminal ligament emerges from the intervertebral disc, passing the nerve medially and attaching the spinal nerve. At the levels L2-L5, the inferior extraforaminal ligaments are only attached to the intervertebral disc, not to the joint capsule. Histologically, the ligaments consisted of mainly collagenous structures. Ligamentous connections exist between lumbar extraforaminal spinal nerves and nearby structures.

  17. An Observational Perspective of Transitional Disks

    Science.gov (United States)

    Espaillat, C.; Muzerolle, J.; Najita, J.; Andrews, S.; Zhu, Z.; Calvet, N.; Kraus, S.; Hashimoto, J.; Kraus, A.; D'Alessio, P.

    Transitional disks are objects whose inner disk regions have undergone substantial clearing. The Spitzer Space Telescope produced detailed spectral energy distributions (SEDs) of transitional disks that allowed us to infer their radial dust disk structure in some detail, revealing the diversity of this class of disks. The growing sample of transitional disks also opened up the possibility of demographic studies, which provided unique insights. There now exist (sub)millimeter and infrared images that confirm the presence of large clearings of dust in transitional disks. In addition, protoplanet candidates have been detected within some of these clearings. Transitional disks are thought to be a strong link to planet formation around young stars and are a key area to study if further progress is to be made on understanding the initial stages of planet formation. Here we provide a review and synthesis of transitional disk observations to date with the aim of providing timely direction to the field, which is about to undergo its next burst of growth as the Atacama Large Millimeter/submillimeter Array (ALMA) reaches its full potential. We discuss what we have learned about transitional disks from SEDs, color-color diagrams, and imaging in the (sub)millimeter and infrared. We note the limitations of these techniques, particularly with respect to the sizes of the clearings currently detectable, and highlight the need for pairing broadband SEDs with multi-wavelength images to paint a more detailed picture of transitional disk structure. We review the gas in transitional disks, keeping in mind that future observations with ALMA will give us unprecedented access to gas in disks, and also observed infrared variability pointing to variable transitional disk structure, which may have implications for disks in general. We then distill the observations into constraints for the main disk-clearing mechanisms proposed to date (i.e., photoevaporation, grain growth, and companions) and

  18. Why Do Disks Form Jets?

    OpenAIRE

    Lynden-Bell, D.

    2002-01-01

    It is argued that jet modelers have given insufficient study to the natural magneto-static configurations of field wound up in the presence of a confining general pressure. Such fields form towers whose height grows with each twist at a velocity comparable to the circular velocity of the accretion disk that turns them. A discussion of the generation of such towers is preceded by a brief history of the idea that quasars, active galaxies, and galactic nuclei contain giant black holes with accre...

  19. Astrophysical disks Collective and Stochastic Phenomena

    CERN Document Server

    Fridman, Alexei M; Kovalenko, Ilya G

    2006-01-01

    The book deals with collective and stochastic processes in astrophysical discs involving theory, observations, and the results of modelling. Among others, it examines the spiral-vortex structure in galactic and accretion disks , stochastic and ordered structures in the developed turbulence. It also describes sources of turbulence in the accretion disks, internal structure of disk in the vicinity of a black hole, numerical modelling of Be envelopes in binaries, gaseous disks in spiral galaxies with shock waves formation, observation of accretion disks in a binary system and mass distribution of luminous matter in disk galaxies. The editors adaptly brought together collective and stochastic phenomena in the modern field of astrophysical discs, their formation, structure, and evolution involving the methodology to deal with, the results of observation and modelling, thereby advancing the study in this important branch of astrophysics and benefiting Professional Researchers, Lecturers, and Graduate Students.

  20. Erasing Data and Recycling of Optical Disks

    Directory of Open Access Journals (Sweden)

    T Fujita

    2007-03-01

    Full Text Available Optical disks, DVDs and CDs, are convenient recording media on which to safely store data for a long period of time. However, the complete data erasure from recorded media is also important for the security of the data. After erasure of data from optical disks, recycling the material is needed in order to recover the valuable components of the optical disks. Here, data erasure methods for optical disks are discussed in the view of material recycling. The main finding of the study is that the explosion of optical disks in water is a very suitable method for complete erasure of data on the disks as well as recycling of their materials.

  1. Structure of the Kuiper Belt Dust Disk

    Science.gov (United States)

    Liou, J.-C.; Kaufmann, D. E.

    An overview of the Kuiper belt dust disk is provided in this chapter. Mutual collisions among Kuiper belt objects should produce a dust disk in the outer solar system similar to the observed circumstellar dust disks. As the Kuiper belt dust particles migrate toward the Sun due to Poynting-Robertson drag, they are perturbed by the giant planets. Mean-motion resonances with Neptune and gravitational scattering by Saturn and Jupiter alter their orbital evolution dramatically. Asa result, large-scale structures are created in the disk. Descriptions of the dynamics involved, and the numerical simulations required to unveil the disk features, are included. Implications for extrasolar planet detection from circumstellar dust disk modeling are also discussed.

  2. Thermal continua of AGN accretion disks

    Science.gov (United States)

    Shields, G. A.; Coleman, H. H.

    1994-01-01

    We have computed the thermal continuum energy distribution of thermal radiation from the atmospheres of supermassive accretion disks around supermassive black holes. Non-LTE radiative transfer is combined with a model of the vertical structure at each radius appropriate to the low effective gravities of these disks. Locally, the Lyman edge of H can be in emission or absorption. When the emission is summed over the disk with Doppler and gravitational redshifts taken into account, the observed continuum typically shows little sign of a discontinuity near the Lyman edge. For relatively cool disks, the Lyman edge is in absorption, but it appears as a slope change extending over several hundred angstroms, rather than an abrupt discontinuity. Disks around Kerr black holes can explain the observed range of soft X-ray luminosities of AGN, but disks around Schwarzschild holes are much too faint in soft X-rays.

  3. Theory of Disk Accretion onto Magnetic Stars

    Directory of Open Access Journals (Sweden)

    Lai Dong

    2014-01-01

    Full Text Available Disk accretion onto magnetic stars occurs in a variety of systems, including accreting neutron stars (with both high and low magnetic fields, white dwarfs, and protostars. We review some of the key physical processes in magnetosphere-disk interaction, highlighting the theoretical uncertainties. We also discuss some applications to the observations of accreting neutron star and protostellar systems, as well as possible connections to protoplanetary disks and exoplanets.

  4. Intervertebral discitis caused by nontypeable Haemophilus influenzae in an adult: Case report

    Science.gov (United States)

    Boulton, R.; Swayamprakasam, A.; Raza, M.

    2012-01-01

    INTRODUCTION: Haemophilus influenzae is a common cause of bacterial meningitis in children and can cause upper respiratory tract infections in adults, but has yet to be reported solely involving intervertebral discitis. PRESENTATION OF CASE: A 67-year-old builder presenting with fever, myalgia and back pain is found to have intervertebral discitis (confirmed on MRI) caused by H. influenzae (identified on blood cultures). DISCUSSION: A nontypeable form of H. influenzae has not been reported causing discitis. We describe a case in a relatively fit individual who was treated successfully with antimicrobial treatment. A preceding upper respiratory tract infection is the presumed source of infection, predisposed by long-term low-dose steroid therapy. CONCLUSION: H. influenzae is a rare, but treatable cause of discitis. PMID:22466113

  5. Continuous lumbar hemilaminectomy for intervertebral disc disease in an Amur tiger (Panthera tigris altaica).

    Science.gov (United States)

    Flegel, Thomas; Böttcher, Peter; Alef, Michaele; Kiefer, Ingmar; Ludewig, Eberhard; Thielebein, Jens; Grevel, Vera

    2008-09-01

    A 13-yr-old Amur tiger (Panthera tigris altaica) was presented for an acute onset of paraplegia. Spinal imaging that included plain radiographs, myelography, and computed tomography performed under general anesthesia revealed lateralized spinal cord compression at the intervertebral disc space L4-5 caused by intervertebral disc extrusion. This extrusion was accompanied by an extensive epidural hemorrhage from L3 to L6. Therefore, a continuous hemilaminectomy from L3 to L6 was performed, resulting in complete decompression of the spinal cord. The tiger was ambulatory again 10 days after the surgery. This case suggests that the potential benefit of complete spinal cord decompression may outweigh the risk of causing clinically significant spinal instability after extensive decompression.

  6. Regression of a symptomatic thoracic disc herniation with a calcified intervertebral disc component

    Directory of Open Access Journals (Sweden)

    Hidayet Sari

    2016-12-01

    Full Text Available There were only a few cases describing spontaneous regression of calcified thoracic disc herniation in the literature. We present a 38-year-old male office worker who had left paramedian-foraminal extruded disc at T7–T8 with calcifications of the T7–T8 and T8–T9 intervertebral discs. This case was unique in that the non-calcified extruded disc material regressed almost completely in 5 months while the calcified intervertebral discs remained the same during the process of regression. This report stresses that regression of the herniated material of the thoracic discs with subsidence of the symptoms is still possible even if the disc material is calcified.

  7. [Comparative study on Chinese medicine and western medicine for treatment of prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Qin, Xin-yan; Li, Xiao-xia; Suteanu, Stefan

    2007-05-01

    To compare therapeutic effects, safety and tolerance of TCM, western medicine and integrated Chinese and western medicine for treatment of acute lumbosacral pain induced by prolapse of lumbar intervertebral disc. Ninety cases were randomly divided into 3 groups, 30 cases in each group. They were treated respectively with western medicine, TCM and combined TCM and western medicine, and the pain intensity, activity, muscular tension, and other indexes were monitored after 7 days and 30 days of treatment. After treatment of 7 days, the combined treatment group in improvement of VAS scores of lumbosacral pain and radiating pain of the lower limbs was superior to the TCM group with no significant difference between the two groups, and in improvement of VAS scores of lumbosacral pain and radiating pain of the lower limbs, Lasegue's sign, activity of spinal column (Schober test and distance from finger tip to floor), etc. were superior to the western medicine group (P prolapse of lumbar intervertebral disc.

  8. [Comparative observation of corresponding channel point selection for treatment of prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Tang, Hua-Sheng

    2008-08-01

    To compare clinical therapeutic effects of acupuncture along channel and routine acupuncture on prolapse of lumbar intervertebral disc. One hundred and sixty-five cases were randomly divided into an observation group (n=85) and a control group (n=80). The observation group were treated with acupuncture at corresponding channel points according to types of the Gallbladder Channel and the Bladder Channel, and the control group were treated with acupuncture at routinely selected acupoints. Their therapeutic effects after treatment of 4 courses and their recurrence rates half a year later were observed. The cured and markedly effective rate of 88.2% and the recurrence rate of 24.0% in the observation group were significantly better than 72.5% and 41.4% in the control group, with significant differences between the two groups (both Pprolapse of lumbar intervertebral disc has significant short-term and long-term therapeutic effects.

  9. [Observation on therapeutic effect of deeply needling Qiangji 4 points on prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    She, Rui-ping

    2008-05-01

    To compare therapeutic effects of deeply needling Qiangji 4 points and routine acupuncture therapy on prolapse of lumbar intervertebral disc. Two hundred and seventy-nine cases were randomly divided into 2 groups, deeply needling group (n=140) and routine acupuncture group (n=139). The deeply needling group were treated with deeply needling Qiangji 4 points, and the routine acupuncture group with acupuncture at Qihaishu (BL 24), Dachangshu (BL 25), Guanyuanshu (BL 26), Xiaochangshu (BL 27) into routine deep. Their therapeutic effects were compared. At the end of the first therapeutic course, the cured rate was 42.1% in the deeply needling group and 28.1% in the routine acupuncture group with significant difference between the two groups (Pprolapse of lumbar intervertebral disc is significantly better than that of routine acupuncture.

  10. [Therapeutic effect of acupuncture on postoperative recovery of prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Li, Yan-qing; Liu, Yan-qing

    2006-08-01

    To evaluate therapeutic effect of comprehensive therapy of acupuncture as main in postoperative recovery of prolapse of lumbar intervertebral disc. Seventy-seven cases were randomly divided into an observation group (n = 40) and a control group (n = 37). The observation group were treated with acupuncture at Shenshu (BL 23), Dachangshu (BL 25), Baliao (BL 31, BL32, BL33, BL 34), Zhibian (BL 54) combined with polarized light, and the control group with western medicine dikeleke 75 mg, once daily. They were treated for 1 month. The cure-markedly effective rate was 95.0% in the observation group and 75.7% in the control group with a significant difference between the two groups (Pprolapse of lumbar intervertebral disc.

  11. [Controlled observation on catgut implantation at acupoint for treatment of prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Xia, Fen-xian; Li, Lin-xing; Sun, Xiao-ying

    2006-03-01

    To compare therapeutic effects of catgut implantation at acupoint and routine acupuncture on prolapse of lumbar intervertebral disc. One hundred and forty cases were randomly divided into a treatment group and a control group, 70 cases in each group. The treatment group were treated with catgut implantation at acupoint, once each week, 3 sessions constituting one course, and the control group with routine acupuncture, once every other day, 10 sessions constituting one course. The effective rate was 95.6% after treatment of one course and 88.2% 3 months later in the treatment group, which were better than 84.6% and 72.3% in the control group, respectively (Both P prolapse of lumbar intervertebral disc, with lower cost.

  12. [Observation on the therapeutic effect of warming needle moxibustion on prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    He, Xing-Wei; Huang, Jian-Hua; Zeng, Li-Yuan

    2007-04-01

    To observe the therapeutic effect of warming needle moxibustion on prolapse of lumbar intervertebral disc. Seventy-eight cases were randomly divided into a test group and a control group, 39 cases in each group. The control group were treated with acupuncture at Shenshu (BIL 23), Mingmen (GV 4), Yaoyangguan (GV 3) and Weizhong (BL, 40), etc. , and the test group with acupuncture at the same acupoints as in the control group plus warming needle moxibustion at Mingmen (GV 4), Yaoyangguan (GV 3) and Weizhong (BL 40). The total effective rate of 94.9% in the test group was significantly better than 71.8% in the control group (P prolapse of lumbar intervertebral disc.

  13. [Control study on analgesic effect of single-point electroacupuncture on prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Huang, Shi-Rong; Shi, Yin-Yu; Zhan, Hong-sheng

    2006-05-01

    To explore an effective method for electroacupuncture treatment of pain in waist and lower extremities due to prolapse of lumbar intervertebral disc. All 98 cases of such disease were randomly divided into a treatment group (n = 53) and a control group (n = 45). The treatment group were treated with local single-point electroacupuncture stimulation, and the control group with routine electroacupuncture stimulation for 8 sessions. The pain in waist and lower extremities in the two groups were continuously evaluated with short-form of McGill pain questionnaire (SF-MPQ). After first treatment, SF-MPQ scores in the two groups were significantly different from those before treatment (P prolapse of lumbar intervertebral disc.

  14. HD 76582's Circumstellar Debris Disk

    Science.gov (United States)

    Marshall, J. P.

    2016-01-01

    The debris disk host star HD 76582 was observed at 450 μm and 850 μm as part of the JCMT/SCUBA-2 debris disk legacy survey `Sub-millimetre Observations of Nearby Stars' (SONS). The sub-millimetre data are inconsistent with a disk undergoing a steady-state collisional cascade. Combining the sub-millimetre (sub-mm) measurements with mid- and far-infrared measurements from Spitzer and Herschel, we simultaneously model the disk's thermal emission and radial extent in a self-consistent manner.

  15. Dust Migration in Gravitationally Active Protoplanetary Disks

    Science.gov (United States)

    Backus, I.; Quinn, T.

    2017-05-01

    Solid growth and planet formation may require dense regions of dust. I investigate dust migration concentration, in gravitationally active protoplanetary disks using high resolution, 3D SPH simulations.

  16. Evaluation of powder metallurgy superalloy disk materials

    Science.gov (United States)

    Evans, D. J.

    1975-01-01

    A program was conducted to develop nickel-base superalloy disk material using prealloyed powder metallurgy techniques. The program included fabrication of test specimens and subscale turbine disks from four different prealloyed powders (NASA-TRW-VIA, AF2-1DA, Mar-M-432 and MERL 80). Based on evaluation of these specimens and disks, two alloys (AF2-1DA and Mar-M-432) were selected for scale-up evaluation. Using fabricating experience gained in the subscale turbine disk effort, test specimens and full scale turbine disks were formed from the selected alloys. These specimens and disks were then subjected to a rigorous test program to evaluate their physical properties and determine their suitability for use in advanced performance turbine engines. A major objective of the program was to develop processes which would yield alloy properties that would be repeatable in producing jet engine disks from the same powder metallurgy alloys. The feasibility of manufacturing full scale gas turbine engine disks by thermomechanical processing of pre-alloyed metal powders was demonstrated. AF2-1DA was shown to possess tensile and creep-rupture properties in excess of those of Astroloy, one of the highest temperature capability disk alloys now in production. It was determined that metallographic evaluation after post-HIP elevated temperature exposure should be used to verify the effectiveness of consolidation of hot isostatically pressed billets.

  17. Hard disks with SCSI interface

    CERN Document Server

    Denisov, O Yu

    1999-01-01

    The testing of 20 models of hard SCSI-disks is carried out: the Fujitsu MAE3091LP; the IBM DDRS-39130, DGHS-318220, DNES-318350, DRHS-36V and DRVS-18V; the Quantum Atlas VI 18.2; the Viking 11 9.1; the Seagate ST118202LW, ST118273LW, ST118273W, ST318203LW, ST318275LW, ST34520W, ST39140LW and ST39173W; and the Western Digital WDE9100-0007, WDE9100-AV0016, WDE9100-AV0030 and WDE9180-0048. All tests ran under the Windows NT 4.0 workstation operating system with Service Pack 4, under video mode with 1024*768 pixel resolution, 32- bit colour depth and V-frequency equal to 85 Hz. The detailed description and characteristics of SCSI stores are presented. Test results (ZD Winstone 99 and ZD WinBench 99 tests) are given in both table and diagram (disk transfer rate) forms. (0 refs).

  18. Kinematics in the Circumnuclear Disk

    Science.gov (United States)

    Mills, Elisabeth; Casey-Clyde, J. Andrew; Rodriguez, Julio; Kruijssen, Diederik; Martin, Sergio; Moser, Lydia; Riquelme, Denise; Harada, Nanase; Zhao, Jun-Hui; Lu, Hauyu

    2018-01-01

    The Circumnuclear Disk (CND) extends from 1.5-5pc in radius around our Galaxy's central supermassive black hole, Sagittarius A*. New ALMA observations reveal that the CND is a more complex system than previously thought, containing multiple streams, filaments and other structures inconsistent with the uniform circular rotation that is typically assumed for this source. We will present position-position-velocity maps of this region using the HNC 3-2 and HCN 3-2 transitions, which reveal line of sight velocities that are highly discontinuous in several regions, suggesting the CND consists of several overlapping and possibly interacting clouds, rather than one continuous and circularized disk. In particular, we single out a uniquely linear stream on the eastern side of this region, which is continuous in both position and velocity, with a size of 3 x 0.1 pc and velocities ranging from -50 to 100 km/s. For this stream, we will also present the results of recently performed orbital fitting, establishing its 3 dimensional position in the central potential around Sagittarius A*.

  19. Changes of proteoglycan and collagen II of the adjacent intervertebral disc in the cervical instability models.

    Science.gov (United States)

    Wu, Bin; Meng, Chunyang; Wang, Haibin; Jia, Cunling; Zhao, Yifeng

    2016-12-01

    Post-operation of cervical decompression fusion and internal fixation (CDF) accelerated adjacent segment disc degeneration (ASD). It is not clear that whether instability of one single segmental accelerates the degeneration of adjacent segment disc. This study aims to explore the effect of cervical instability on the change of morphology and biochemistry in adjective segment (above) in the L5/6 cervical instability rabbit models. Thirty-two mature New Zealand white rabbits (3000±250g) were randomly divided into two groups, control group (n=8) and model group (n=24). The animal models were established by destruction of partly annulus fibrosus and suction of nucleus pulposus. ASD was detected by X-ray after 4, 8 or 12 weeks surgery (8 model rabbits of each time). Animals were then euthanatized for cervical intervertebral disc tissue samples separation. Histomorphology, proteoglycan and collagen II of samples were detected. Histomorphology data showed that notochord cells were decreased in C4/5 cervical nucleus pulposus and were replaced by fibroblast-like cells; a small amount cartilage cells were emerged; intervertebral disc anulus fibrosus becomes rough, disorganized, hyaline degeneration and pigmentation, in which contained fibrocartilage cells and cracks between the inner and outer layers. Proteoglycan content of nucleus pulposus was significantly decreased. Meanwhile, type II collagen of nucleus pulposus and annulus was also apparently reduced. Cervical instability can alter morphology and reduce the content of proteoglycan and collagen II in adjacent intervertebral disc, thereby contributes adjacent intervertebral disc degeneration. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Preliminary results of a soft novel lumbar intervertebral prothesis (DIAM) in the degenerative spinal pathology.

    Science.gov (United States)

    Mariottini, A; Pieri, S; Giachi, S; Carangelo, B; Zalaffi, A; Muzii, F V; Palma, L

    2005-01-01

    The authors report a series of 43 patients suffering from lower limb pain, almost constantly associated with chronic or acute backpain, treated by microsurgical nerve root decompression and by implantation of a soft intervertebral prothesis (DIAM). Satisfying results were obtained in 97% of cases, inducing the authors to consider the device a reliable tool for curing low-back pain and sciatica. Selection criteria are exposed and discussed.

  1. Quantifying the effect of intervertebral cartilage on neutral posture in the necks of sauropod dinosaurs

    OpenAIRE

    Taylor, Michael P.

    2014-01-01

    Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises) the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the ...

  2. Imaging of degenerative lumbar intervertebral discs; linking anatomy, pathology and imaging.

    Science.gov (United States)

    Adams, Ashok; Roche, Oran; Mazumder, Asif; Davagnanam, Indran; Mankad, Kshitij

    2014-09-01

    Low back pain is a common medical condition that has significant implications for healthcare providers and the UK economy. Low back pain can be classified as 'specific' in which an underlying pathophysiological mechanism is identified (eg, herniated intervertebral disc). Advanced imaging should be performed in this situation and in those patients in whom systemic disease is strongly suspected. In the majority (approximately 90%), low back pain in 'non specific' and there is a weak correlation with imaging abnormalities. This is an area of ongoing research and remains controversial in terms of imaging approach and treatment (eg, theory of discogenic pain, interpretation and treatment of endplate changes). With regards Modic endplate changes, current research suggests that an infective component may be involved that may identify novel potential treatments in patients with chronic low back pain refractory to other treatment modalities. MRI is the imaging modality of choice for the assessment of degenerative changes in intervertebral discs. MRI has superior soft tissue contrast resolution when compared to other imaging modalities (eg, plain radiography, CT). An understanding of normal anatomy and MR appearances of intervertebral discs, particularly with regards to how these appearances change with advancing age, is required to aid image interpretation. Knowledge of the spectrum of degenerative processes that may occur in the intervertebral discs is required in order to identify and explain abnormal MRI appearances. As the communication of MRI findings may guide therapeutic decision making and surgical intervention, the terminology used by radiologists must be accurate and consistent. Therefore, description of degenerative disc changes in the current paper is based on the most up-to-date recommendations, the aim being to aid reporting by radiologists and interpretation of reports by referring clinicians. Published by the BMJ Publishing Group Limited. For permission to

  3. Anti-inflammatory Chitosan/Poly-γ-glutamic acid nanoparticles control inflammation while remodeling extracellular matrix in degenerated intervertebral disc.

    Science.gov (United States)

    Teixeira, Graciosa Q; Leite Pereira, Catarina; Castro, Flávia; Ferreira, Joana R; Gomez-Lazaro, Maria; Aguiar, Paulo; Barbosa, Mário A; Neidlinger-Wilke, Cornelia; Goncalves, Raquel M

    2016-09-15

    Intervertebral disc (IVD) degeneration is one of the most common causes of low back pain (LBP), the leading disorder in terms of years lived with disability. Inflammation can play a role in LPB, while impairs IVD regeneration. In spite of this, different inflammatory targets have been purposed in the context of IVD regeneration. Anti-inflammatory nanoparticles (NPs) of Chitosan and Poly-(γ-glutamic acid) with a non-steroidal anti-inflammatory drug, diclofenac (Df), were previously shown to counteract a pro-inflammatory response of human macrophages. Here, the effect of intradiscal injection of Df-NPs in degenerated IVD was evaluated. For that, Df-NPs were injected in a bovine IVD organ culture in pro-inflammatory/degenerative conditions, upon stimulation with needle-puncture and interleukin (IL)-1β. Df-NPs were internalized by IVD cells, down-regulating IL-6, IL-8, MMP1 and MMP3, and decreasing PGE2 production, compared with IL-1β-stimulated IVD punches. Interestingly, at the same time, Df-NPs promoted an up-regulation of extracellular matrix (ECM) proteins, namely collagen type II and aggrecan. Allover, this study suggests that IVD treatment with Df-NPs not only reduces inflammation, but also delays and/or decreases ECM degradation, opening perspectives to new intradiscal therapies for IVD degeneration, based on the modulation of inflammation. Degeneration of the IVD is an age-related progressive process considered to be the major cause of spine disorders. The pro-inflammatory environment and biomechanics of the degenerated IVD is a challenge for regenerative therapies. The novelty of this work is the intradiscal injection of an anti-inflammatory therapy based on Chitosan (Ch)/Poly-(γ-glutamic acid) (γ-PGA) nanoparticles (NPs) with an anti-inflammatory drug (diclofenac, Df), previously developed by us. This drug delivery system was tested in a pro-inflammatory/degenerative intervertebral disc ex vivo model. The main findings support the success of an anti

  4. ADAMTS5 Deficiency Protects Mice From Chronic Tobacco Smoking-induced Intervertebral Disc Degeneration.

    Science.gov (United States)

    Ngo, Kevin; Pohl, Pedro; Wang, Dong; Leme, Adriana S; Lee, Joon; Di, Peter; Roughley, Peter; Robbins, Paul D; Niedernhofer, Laura J; Sowa, Gwendolyn; Kang, James D; Shapiro, Steven S; Vo, Nam V

    2017-10-15

    ADAMTS5-deficient and wild type (WT) mice were chronically exposed to tobacco smoke to investigate effects on intervertebral disc degeneration (IDD). The aim of this study was to demonstrate a role for ADAMTS5 in mediating tobacco smoking-induced IDD. We previously demonstrated that chronic tobacco smoking causes IDD in mice because, in part, of proteolytic destruction of disc aggrecan. However, it was unknown which matrix proteinase(s) drive these detrimental effects. Three-month-old WT (C57BL/6) and ADAMTS5 mice were chronically exposed to tobacco smoke (four cigarettes/day, 5 day/week for 6 months). ADAMTS-mediated cleavage of disc aggrecan was analyzed by Western blot. Disc total glycosaminoglycan (GAG) content was assessed by dimethyl methylene blue assay and safranin O/fast green histology. Vertebral osteoporosity was measured by microcomputed tomography. Human nucleus pulposus (hNP) cell cultures were also exposed directly to tobacco smoke extract (TSE), a condensate containing the water-soluble compounds inhaled by smokers, to measure ADAMTS5 expression and ADAMTS-mediated cleavage of aggrecan. Activation of nuclear factor (NF)-κB, a family of transcription factors essential for modulating the cellular response to stress, was measured by immunofluorescence assay. Genetic depletion of ADAMTS5 prevented vertebral bone loss, substantially reduced loss of disc GAG content, and completely obviated ADAMTS-mediated proteolysis of disc aggrecan within its interglobular domain (IGD) in mice following exposure to tobacco smoke. hNP cell cultures exposed to TSE also resulted in upregulation of ADAMTS5 protein expression and a concomitant increase in ADAMTS-mediated cleavage within aggrecan IGD. Activation of NF-κB, known to be required for ADAMTS5 gene expression, was observed in both TSE-treated hNP cell cultures and disc tissue of tobacco smoke-exposed mice. The findings demonstrate that ADAMTS5 is the primary aggrecanase mediating smoking-induced disc

  5. Protective effects of cannabidiol on lesion-induced intervertebral disc degeneration.

    Directory of Open Access Journals (Sweden)

    João W Silveira

    Full Text Available Disc degeneration is a multifactorial process that involves hypoxia, inflammation, neoinnervation, accelerated catabolism, and reduction in water and glycosaminoglycan content. Cannabidiol is the main non-psychotropic component of the Cannabis sativa with protective and anti-inflammatory properties. However, possible therapeutic effects of cannabidiol on intervertebral disc degeneration have not been investigated yet. The present study investigated the effects of cannabidiol intradiscal injection in the coccygeal intervertebral disc degeneration induced by the needle puncture model using magnetic resonance imaging (MRI and histological analyses. Disc injury was induced in the tail of male Wistar rats via a single needle puncture. The discs selected for injury were punctured percutaneously using a 21-gauge needle. MRI and histological evaluation were employed to assess the results. The effects of intradiscal injection of cannabidiol (30, 60 or 120 nmol injected immediately after lesion were analyzed acutely (2 days by MRI. The experimental group that received cannabidiol 120 nmol was resubmitted to MRI examination and then to histological analyses 15 days after lesion/cannabidiol injection. The needle puncture produced a significant disc injury detected both by MRI and histological analyses. Cannabidiol significantly attenuated the effects of disc injury induced by the needle puncture. Considering that cannabidiol presents an extremely safe profile and is currently being used clinically, these results suggest that this compound could be useful in the treatment of intervertebral disc degeneration.

  6. Protective effects of cannabidiol on lesion-induced intervertebral disc degeneration.

    Science.gov (United States)

    Silveira, João W; Issy, Ana Carolina; Castania, Vitor A; Salmon, Carlos E G; Nogueira-Barbosa, Marcello H; Guimarães, Francisco S; Defino, Helton L A; Del Bel, Elaine

    2014-01-01

    Disc degeneration is a multifactorial process that involves hypoxia, inflammation, neoinnervation, accelerated catabolism, and reduction in water and glycosaminoglycan content. Cannabidiol is the main non-psychotropic component of the Cannabis sativa with protective and anti-inflammatory properties. However, possible therapeutic effects of cannabidiol on intervertebral disc degeneration have not been investigated yet. The present study investigated the effects of cannabidiol intradiscal injection in the coccygeal intervertebral disc degeneration induced by the needle puncture model using magnetic resonance imaging (MRI) and histological analyses. Disc injury was induced in the tail of male Wistar rats via a single needle puncture. The discs selected for injury were punctured percutaneously using a 21-gauge needle. MRI and histological evaluation were employed to assess the results. The effects of intradiscal injection of cannabidiol (30, 60 or 120 nmol) injected immediately after lesion were analyzed acutely (2 days) by MRI. The experimental group that received cannabidiol 120 nmol was resubmitted to MRI examination and then to histological analyses 15 days after lesion/cannabidiol injection. The needle puncture produced a significant disc injury detected both by MRI and histological analyses. Cannabidiol significantly attenuated the effects of disc injury induced by the needle puncture. Considering that cannabidiol presents an extremely safe profile and is currently being used clinically, these results suggest that this compound could be useful in the treatment of intervertebral disc degeneration.

  7. Treatment of intervertebral disc degenerative disease using percutaneous nucleotomy–an overview of less invasive procedures

    Directory of Open Access Journals (Sweden)

    Miran Jeromel

    2014-04-01

    Full Text Available Background: Less invasive treatment methods for intervertebral disc disease and decompression of neural structures as a consequence of contained disc herniation represent an alternative to surgical procedure. Percutaneus nucleotomy uses a percutaneous approach to the intervertebral disc. The article presents the evolution of numerous procedureds in clinical practice.Methods: Percutaneous nucleoplasty is a fluoroscopy-guided procedure which enables controlled and safe entrance into the intervertebral disc. The procedure is performed under strict aseptic conditions, using a local anaesthesia with the patient under analgosedation. Based on the principle of therapeutic intradiscal action, the procedures can be divided into three groups: chemical (chemonucleolysis with chimopapain, alcohol, ozone, mechanical (automated percutaneous lumbar discectomy – APLD, arthroscopic discectomy and thermical methods (laser, radiofrequency ablation, intradiscal electrothermal annuloplasty – IDET, Coblation®.Results: Percutaneous nucleotomy by the majority of the mentioned procedures results in a therapeutic effect (reduction of pain and decompression of neural structures. Fast recovery represents a major advantage of less invasive treatment.Conclusions: Less invasive method (nucleotomy using different procedures represents a successful alternative approach to surgical discectomy. Proper patient selection and safe technique are mandatory in order to achieve a good clinical outcome.

  8. Role of interleukin-17 in chondrocytes of herniated intervertebral lumbar discs.

    Science.gov (United States)

    Tian, Peng; Li, Zhi-Jun; Fu, Xin; Ma, Xin-Long

    2015-07-01

    Lumbar disc herniation (LDH) is a common cause of lumbosacral radiculopathy. An autoimmune response to a herniated nucleus pulposus (NP) has been suggested to play an important role in the initiation of radiculopathy. Interleukin-17 (IL-17) is a cytokine associated with inflammation and autoimmunity. The presence of IL-17 has been studied in patients with LDH; however, extensive investigation into the expression of IL-17 in different disc pathologies of LDH has not yet been conducted. The aim of the present study was to investigate the role of neovascularization and hypertrophic chondrocytes in herniated intervertebral lumbar discs. Fifty-two intervertebral lumbar disc specimens were extracted from 46 patients with LDH and were subsequently classified as either contained or non-contained disc herniation (CDH and NCDH, respectively). The specimens were stained with hematoxylin and eosin or toluidine blue, or were immunostained with polyclonal antibodies to IL-17 using the streptavidin-peroxidase method. The neovascular tissue and staining results were graded to establish the histological differences between the two herniation types. The intervertebral discs (IVDs) obtained from patients with NCDH showed significantly more neovascularization and granulation tissue than the discs obtained from patients with CDH (Pherniated IVDs.

  9. Magnetic resonance imaging for each type of herniated cervical intervertebral disc

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ham Gyum [Ansan 1 College, Ansan (Korea, Republic of)

    2000-04-15

    The classification of herniated intervertebral cervical disc types are clinically important, as treatment methods would be slightly different according to the specific type of the herniated disc. 423 patients who suffered from herniated intervertebral cervical discs were tested with Magnetic Resonance Imaging (MRI), to distinguish the type of the herniated discs. The following are the results: The age of the patients tested ranged from 16 to 75 years old and the mean age of the patients was 41.4 years of age. There were twice as many male patients with a ratio of 288: 135 men to women. 101 patients suffered from single herniated discs while 322 patients suffered from multi-herniated discs. Of single herniated disc injuries. 52 patients had protruded discs (52%) while 25 patients had extruded discs (25%). 21 Patients (21%) had herniated intervertebral discs between C{sub 4} {approx} C{sub 5} and 51 patients (50%) and had the same injury between C{sub 5} and C{sub 6}. Of multi-herniated disc injuries. 140 patients had protruded discs (44%). while 45 patients had extruded discs (14%). 54 patients had both protruded and extruded discs (17%). 36 patients (11%). herniated discs C{sub 3} {approx} C{sub 6}: 69 patients (21%). herniated discs C{sub 3} {approx} C{sub 7}: 47 patients (15%) herniated discs C{sub 4} {approx} C{sub 6} and 67 patients (20%) herniated discs C{sub 5} {approx} C{sub 7}.

  10. Comparison between cranial thoracic intervertebral disc herniations in German Shepherd dogs and other large breed dogs.

    Science.gov (United States)

    Gaitero, Luis; Nykamp, Stephanie; Daniel, Rob; Monteith, Gabrielle

    2013-01-01

    Cranial thoracic intervertebral disc herniations have been reported to be rare in dogs due to the presence of the intercapital ligament, however some studies have proposed they may not be uncommon in German Shepherd dogs. The purpose of this retrospective study was to compare cranial thoracic intervertebral disc herniations in German Shepherd dogs and other large breed dogs (control group). Medical records at the Ontario Veterinary College were searched for German Shepherd dogs and other large breed dogs that had magnetic resonance imaging studies including the T1-T9 region. For each dog and each disc space from T1-T9, three variables (compression, disc degeneration, and herniation) were recorded and graded based on review of sagittal T2-weighted images. Twenty-three German Shepherd dogs and 47 other large breed dogs met inclusion criteria. The German Shepherd dog group had higher scores than the control group for compression (P = 0.0099) and herniation (P dog group, intervertebral discs T2-T3 and T4-T5 had an increased risk for compression and T3-T4 had an increased risk for compression and herniation. Findings from this study indicated that German Shepherd dogs may be more likely than other large breed dogs to have spinal cord compression due to cranial thoracic disc herniations. Imaging of the cranial thoracic spine, including T2-T3, is recommended for German Shepherd dogs with T3-L3 neurological signs. © 2012 Veterinary Radiology & Ultrasound.

  11. Structure, function, aging and turnover of aggrecan in the intervertebral disc.

    Science.gov (United States)

    Sivan, Sarit Sara; Wachtel, Ellen; Roughley, Peter

    2014-10-01

    Aggrecan is the major non-collagenous component of the intervertebral disc. It is a large proteoglycan possessing numerous glycosaminoglycan chains and the ability to form aggregates in association with hyaluronan. Its abundance and unique molecular features provide the disc with its osmotic properties and ability to withstand compressive loads. Degradation and loss of aggrecan result in impairment of disc function and the onset of degeneration. This review summarizes current knowledge concerning the structure and function of aggrecan in the normal intervertebral disc and how and why these change in aging and degenerative disc disease. It also outlines how supplementation with aggrecan or a biomimetic may be of therapeutic value in treating the degenerate disc. Aggrecan abundance reaches a plateau in the early twenties, declining thereafter due to proteolysis, mainly by matrix metalloproteinases and aggrecanases, though degradation of hyaluronan and non-enzymic glycation may also participate. Aggrecan loss is an early event in disc degeneration, although it is a lengthy process as degradation products may accumulate in the disc for decades. The low turnover rate of the remaining aggrecan is an additional contributing factor, preventing protein renewal. It may be possible to retard the degenerative process by restoring the aggrecan content of the disc, or by supplementing with a bioimimetic possessing similar osmotic properties. This review provides a basis for scientists and clinicians to understand and appreciate the central role of aggrecan in the function, degeneration and repair of the intervertebral disc. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Matrix Remodeling During Intervertebral Disc Growth and Degeneration Detected by Multichromatic FAST Staining

    Science.gov (United States)

    Leung, Victor Y.L.; Chan, Wilson C.W.; Hung, Siu-Chun; Cheung, Kenneth M.C.; Chan, Danny

    2009-01-01

    Various imaging techniques have been used to assess degeneration of the intervertebral disc, including many histological methods, but cartilage-oriented histological stains do not clearly show the comparatively complex structures of the disc. In addition, there is no integrated method to assess efficiently both the compartmental organization and matrix composition in disc samples. In this study, a novel histological method, termed FAST staining, has been developed to investigate disc growth and degeneration by sequential staining with fast green, Alcian blue, Safranin-O, and tartrazine to generate multichromatic histological profiles (FAST profiles). This identifies the major compartments of the vertebra-disc region, including the cartilaginous endplate and multiple zones of the annulus fibrosus, by specific FAST profile patterns. A disc degeneration model in rabbit established using a previously described puncture method showed gradual but profound alteration of the FAST profile during disc degeneration, supporting continual alteration of glycosaminoglycan. Changes of the FAST profile pattern in the nucleus pulposus and annulus fibrosus of the postnatal mouse spine suggested matrix remodeling activity during the growth of intervertebral discs. In summary, we developed an effective staining method capable of defining intervertebral disc compartments in detail and showing matrix remodeling events within the disc. The FAST staining method may be used to develop a histopathological grading system to evaluate disc degeneration or malformation. (J Histochem Cytochem 57:249–256, 2009) PMID:19001641

  13. [Manipulative reduction for lumbar intervertebral disc herniation: a controlled clinical trial].

    Science.gov (United States)

    Zhang, Wei-bin; Cao, Yu; Sun, Yong-an; Wang, Chun-sheng; Wang, Ying; Dong, Shi-long; Ren, Guo-zhong; Yang, Ying-xin; Zhang, Jing-zhong

    2008-04-01

    To investigate the effects of manipulative reduction on pain and clinical curative effect in patients with lumbar intervertebral disc herniation. Eleven thousands one hundred and twenty-eight patients with lumbar intervertebral disc herniation from our hospital were enrolled from November 1986 to June 2007. They were randomly divided into control group and treatment group. Patients of the control group received lumbar traction and various physiotherapies. Patients of the treatment group received manipulative reduction, besides the treatment in the control group. The treatment was performed once a day,ten times as a course. Curative effects were assessed three courses later. Pain was evaluated by visual analogue scale before and after the treatment. No significant difference in the score of visual analogue scale was found before the treatment in the two groups (P > 0.05). As compared with the score before treatment,it was decreased by 4.73 points after treatment in the control group, and decreased by 6.37 points in the treatment group. The decrease was more significant in the treatment group than the control group (P Manipulative reduction for lumbar intervertebral disc herniation can remarkably relieve lumbar pain and improve clinical curative effect.

  14. Improving the thin-disk models of circumstellar disk evolution. The 2+1-dimensional model

    Science.gov (United States)

    Vorobyov, Eduard I.; Pavlyuchenkov, Yaroslav N.

    2017-09-01

    Context. Circumstellar disks of gas and dust are naturally formed from contracting pre-stellar molecular cores during the star formation process. To study various dynamical and chemical processes that take place in circumstellar disks prior to their dissipation and transition to debris disks, the appropriate numerical models capable of studying the long-term disk chemodynamical evolution are required. Aims: We improve the frequently used 2D hydrodynamical model for disk evolution in the thin-disk limit by employing a better calculation of the disk thermal balance and adding a reconstruction of the disk vertical structure. Together with the hydrodynamical processes, the thermal evolution is of great importance since it influences the strength of gravitational instability and the chemical evolution of the disk. Methods: We present a new 2+1-dimensional numerical hydrodynamics model of circumstellar disk evolution, where the thin-disk model is complemented with the procedure for calculating the vertical distributions of gas volume density and temperature in the disk. The reconstruction of the disk vertical structure is performed at every time step via the solution of the time-dependent radiative transfer equations coupled to the equation of the vertical hydrostatic equilibrium. Results: We perform a detailed comparison between circumstellar disks produced with our previous 2D model and with the improved 2+1D approach. The structure and evolution of resulting disks, including the differences in temperatures, densities, disk masses, and protostellar accretion rates, are discussed in detail. Conclusions: The new 2+1D model yields systematically colder disks, while the in-falling parental clouds are warmer. Both effects act to increase the strength of disk gravitational instability and, as a result, the number of gravitationally bound fragments that form in the disk via gravitational fragmentation as compared to the purely 2D thin-disk simulations with a simplified

  15. The effect of degenerative morphological changes of the intervertebral disc on the lumbar spine biomechanics: a poroelastic finite element investigation.

    Science.gov (United States)

    Galbusera, Fabio; Schmidt, Hendrik; Neidlinger-Wilke, Cornelia; Wilke, Hans-Joachim

    2011-08-01

    Intervertebral disc degeneration involves changes in the spinal anatomical structures. The mechanical relevance of the following changes was investigated: disc height, endplate sclerosis, disc water content, permeability and depressurisation. A poroelastic nonlinear finite element model of the L4-L5 human spine segments was employed. Loads represented a daily cycle (500 N compression combined with flexion-extension motion for 16 h followed by 200 N compression for 8 h). In non-degenerative conditions, the model predicted a diurnal axial displacement of 1.32 mm and a peak intradiscal pressure of 0.47 MPa. Axial displacement, facet force and range of motion in flexion-extension are decreased by decreasing disc height. By decreasing the initial water content, axial displacement, facet force and fluid loss were all reduced. Endplate sclerosis did not have a significant influence on the calculated results. Depressurisation determined an increase of the disc effective stress, possibly inducing failure. Degenerative instability was not calculated in any simulations.

  16. Protective effect of p53 on the viability of intervertebral disc nucleus pulposus cells under low glucose condition.

    Science.gov (United States)

    Xiong, Xifeng; Dai, Libing; Liang, Weiguo; Zhang, Jinli; Qin, Shengnan; Cao, Wenjuan; Ye, Dongping; Liang, Peihong; Liu, Zhihe

    2017-09-02

    P53 is a famous cancer suppressor and plays key roles in metabolism. Intervertebral disc (IVD) is the largest avascular cartilaginous structure in humans and its degeneration is a common cause of spine diseases initiated from damaged nucleus pulposus (NP) cells. The potential cause of disc degeneration has been attributed to aging, genetic factors, mechanical factors and nutrition. In this study, we found that p53 decreased and leaked to the cytoplasm in NP cells as the glucose level decreases, in contrast to cancer cells in which p53 increases and concentrates to the nuclei. Comparing with in p53 knockdown NP cells, relative high p53 expression in normal control NP cells inhibited autophagy and the pentose phosphate pathway. Furthermore, the expression of Sox 9 and type II collagen were higher in p53 normal control than p53 knockdown NP cells. Based on these results, we believe that relative high p53 facilitates NP cell viability and integrity. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Precision of lumbar intervertebral measurements: does a computer-assisted technique improve reliability?

    Science.gov (United States)

    Pearson, Adam M; Spratt, Kevin F; Genuario, James; McGough, William; Kosman, Katherine; Lurie, Jon; Sengupta, Dilip K

    2011-04-01

    Comparison of intra- and interobserver reliability of digitized manual and computer-assisted intervertebral motion measurements and classification of "instability." To determine if computer-assisted measurement of lumbar intervertebral motion on flexion-extension radiographs improves reliability compared with digitized manual measurements. Many studies have questioned the reliability of manual intervertebral measurements, although few have compared the reliability of computer-assisted and manual measurements on lumbar flexion-extension radiographs. Intervertebral rotation, anterior-posterior (AP) translation, and change in anterior and posterior disc height were measured with a digitized manual technique by three physicians and by three other observers using computer-assisted quantitative motion analysis (QMA) software. Each observer measured 30 sets of digital flexion-extension radiographs (L1-S1) twice. Shrout-Fleiss intraclass correlation coefficients for intra- and interobserver reliabilities were computed. The stability of each level was also classified (instability defined as >4 mm AP translation or 10° rotation), and the intra- and interobserver reliabilities of the two methods were compared using adjusted percent agreement (APA). Intraobserver reliability intraclass correlation coefficients were substantially higher for the QMA technique THAN the digitized manual technique across all measurements: rotation 0.997 versus 0.870, AP translation 0.959 versus 0.557, change in anterior disc height 0.962 versus 0.770, and change in posterior disc height 0.951 versus 0.283. The same pattern was observed for interobserver reliability (rotation 0.962 vs. 0.693, AP translation 0.862 vs. 0.151, change in anterior disc height 0.862 vs. 0.373, and change in posterior disc height 0.730 vs. 0.300). The QMA technique was also more reliable for the classification of "instability." Intraobserver APAs ranged from 87 to 97% for QMA versus 60% to 73% for digitized manual

  18. Observational constraints on Acrretion disk formation

    Science.gov (United States)

    Harsono, Daniel; Jørgensen, Jes; van Dishoeck, Ewine; Hogerheijde, Michiel; Bruderer, Simon; Persson, Magnus; Mottram, Joseph

    2013-07-01

    Stable rotationally supported disks (RSDs) are important for the star and planet formation process. The structure and stability of the RSDs are linked to the accretion process onto the star and the evolution of the protostellar system. Additionally, these disks are composed of infalling material that encounter a wide range of physical conditions. The history of these changes affect the chemical structure and evolution of the accretion disk and, thus, the material out of which planets are formed. The formation of RSDs is not well understood and it is unclear from the existing data at which stage the young disks are rotationally supported. Here, we present new PdBI observations of 13CO and C18O toward 4 Class I YSOs with higher spatial resolution and significantly higher sensitivity than previously possible. The high quality data allow us to constrain the physical structure of the young embedded disks which are rotationally supported within the inner 100 AU radius. Furthermore, the extent of the RSD is smaller than that of the dust disk. The observed physical structure of embedded disks are compared to semi-analytical disk formation models which suggests that the formation process is consistent with inside-out formation. ALMA is needed to confirm the extent of the rotationally supported structure.

  19. Scaling Ratios and Triangles in Siegel Disks

    DEFF Research Database (Denmark)

    Buff, Xavier; Henriksen, Christian

    1999-01-01

    Let f(z)=e^{2i\\pi \\theta} + z^2, where \\theta is a quadratic irrational. McMullen proved that the Siegel disk for f is self-similar about the critical point, and we show that if \\theta = (\\sqrt{5}-1)/2 is the golden mean, then there exists a triangle contained in the Siegel disk, and with one...

  20. 10 MB disk platter from CDC 7638

    CERN Multimedia

    1974-01-01

    This magnetic disk was one of three which interfaced with various Control Data machines. This single platter came from a Control Data 7638 Disk Storage Subsystem and could contain up to 10MB - about the size of a few MP4's on your iPod.

  1. The Transitional Disks Associated With Herbig Stars

    Science.gov (United States)

    Grady, C.; Fukagawa, M.; Maruta, Y.; Ohta, Y.; Wisniewski, J.; Lomax, J.; Hashimoto, J.; Currie, T.; Okamoto, Y.; Momose, M.; hide

    2015-01-01

    As part of the Strategic Exploration of Exoplanets and Disks with Subaru YSO survey, we have surveyed a number of Herbig B-F stars mainly at H-band using Polarimetric Differential Imaging + Angular differential imaging. Historically, Herbig stars have been sorted by the shape of the IR SEDs into those which can be fit by power laws over 1-200 micrometers (Meeus et al. 2001, group II), and those which can be interpreted as a power law + a blackbody component (Meeus group I) or as transitional or pre-transitional disks (Maaskant et al. 2013). Meeus group II disks, when imaged with HiCIAO show featureless disks with depolarization along the projection of the disk semi-minor axis (Kusakabe et al. 2012). This is what we had expected to see for the Meeus group I disks, except for the addition of wide gaps or central cavities. Instead we find wild diversity, suggesting that transitional disks are highly perturbed compared to Meeus group II disks. To date, similar structure continues to be observed as higher Strehl ratio imagery becomes available.

  2. Angular Momentum Transport in Accretion Disks

    DEFF Research Database (Denmark)

    E. Pessah, Martin; Chan, Chi-kwan; Psaltis, Dimitrios

    2007-01-01

    if the resolution were set equal to the natural dissipation scale in astrophysical disks. We conclude that, in order for MRI-driven turbulent angular momentum transport to be able to account for the large value of the effective alpha viscosity inferred observationally, the disk must be threaded by a significant...

  3. The Kinematics of Galactic Stellar Disks

    NARCIS (Netherlands)

    Merrifield, M. R.; Kuijken, K.

    1998-01-01

    Abstract: The disks of galaxies are primarily stellar systems, and fundamentally dynamical entities. Thus, to fully understand galactic disks, we must study their stellar kinematics as well as their morphologies. Observational techniques have now advanced to a point where quite detailed

  4. Protoplanetary disks and exoplanets in scattered light

    NARCIS (Netherlands)

    Stolker, T.

    2017-01-01

    High-contrast imaging facilitates the direct detection of protoplanetary disks in scattered light and self-luminous exoplanets on long-period orbits. The combined power of extreme adaptive optics and differential imaging techniques delivers high spatial resolution images of disk morphologies down to

  5. Dissecting disks around B-type protostars

    NARCIS (Netherlands)

    Sanchez-Monge, Alvaro; Cesaroni, Riccardo; Beltran, Maite; Kumar, M. S. Nanda; Stanke, Thomas; Zinnecker, Hans; Etoka, Sandra; Galli, Daniele; Hummel, Christian A.; Moscadelli, Luca; Preibisch, Thomas; Ratzka, Thorsten; van der Tak, Floris; Vig, Sarita; Walmsley, C. Malcolm; Wang, Kuo-Song

    Recent theoretical models indicate that OB-type stars could form through disk-mediated accretion, like their low mass counterparts. However, on the observational side, circumstellar disks appear still elusive, especially around the most massive (proto)stars. As for early B-type (proto)stars, an ever

  6. Circumstellar disks around binary stars in Taurus

    Energy Technology Data Exchange (ETDEWEB)

    Akeson, R. L. [NASA Exoplanet Science Institute, IPAC/Caltech, Pasadena, CA 91125 (United States); Jensen, E. L. N. [Swarthmore College, Department of Physics and Astronomy, Swarthmore, PA 19081 (United States)

    2014-03-20

    We have conducted a survey of 17 wide (>100 AU) young binary systems in Taurus with the Atacama Large Millimeter Array (ALMA) at two wavelengths. The observations were designed to measure the masses of circumstellar disks in these systems as an aid to understanding the role of multiplicity in star and planet formation. The ALMA observations had sufficient resolution to localize emission within the binary system. Disk emission was detected around all primaries and 10 secondaries, with disk masses as low as 10{sup –4} M {sub ☉}. We compare the properties of our sample to the population of known disks in Taurus and find that the disks from this binary sample match the scaling between stellar mass and millimeter flux of F{sub mm}∝M{sub ∗}{sup 1.5--2.0} to within the scatter found in previous studies. We also compare the properties of the primaries to those of the secondaries and find that the secondary/primary stellar and disk mass ratios are not correlated; in three systems, the circumsecondary disk is more massive than the circumprimary disk, counter to some theoretical predictions.

  7. Disk Evolution and the Fate of Water

    Science.gov (United States)

    Hartmann, Lee; Ciesla, Fred; Gressel, Oliver; Alexander, Richard

    2017-10-01

    We review the general theoretical concepts and observational constraints on the distribution and evolution of water vapor and ice in protoplanetary disks, with a focus on the Solar System. Water is expected to freeze out at distances greater than 1-3 AU from solar-type central stars; more precise estimates are difficult to obtain due to uncertainties in the complex processes involved in disk evolution, including dust growth, settling, and radial drift, and the level of turbulence and viscous dissipation within disks. Interferometric observations are now providing constraints on the positions of CO snow lines, but extrapolation to the unresolved regions where water ice sublimates will require much better theoretical understanding of mass and angular momentum transport in disks as well as more refined comparison of observations with sophisticated disk models.

  8. Disk accretion onto a magnetized star

    Directory of Open Access Journals (Sweden)

    Istomin Ya. N.

    2014-01-01

    Full Text Available The problem of interaction of the rotating magnetic field, frozen to a star, with a thin well conducting accretion disk is solved exactly. It is shown that a disk pushes the magnetic field lines towards a star, compressing the stellar dipole magnetic field. At the point of corotation, where the Keplerian rotation frequency coincides with the frequency of the stellar rotation, the loop of the electric current appears. The electric currents flow in the magnetosphere only along two particular magnetic surfaces, which connect the corotation region and the inner edge of a disk with the stellar surface. It is shown that the closed current surface encloses the magnetosphere. Rotation of a disk is stopped at some distance from the stellar surface, which is 0.55 of the corotation radius. Accretion from a disk spins up the stellar rotation. The angular momentum transferred to the star is determined.

  9. Reverberation Mapping of AGN Accretion Disks

    Science.gov (United States)

    Fausnaugh, Michael; AGN STORM Collaboration

    2017-01-01

    I will discuss new reverberation mapping results that allow us to investigate the temperature structure of AGN accretion disks. By measuring time-delays between broad-band continuum light curves, we can determine the size of the disk as a function of wavelength. I will discuss the detection of continuum lags in NGC 5548 reported by the AGN STORM project and implications for the accretion disk. I will also present evidence for continuum lags in two other AGN for which we recently measured black hole masses from continuum-Hbeta reverberations. The mass measurements allow us to compare the continuum lags to predictions from standard thin disk theory, and our results indicate that the accretion disks are larger than the simplest expectations.

  10. Continuum Reverberation Mapping of AGN Accretion Disks

    Directory of Open Access Journals (Sweden)

    Michael M. Fausnaugh

    2017-12-01

    Full Text Available We show recent detections of inter-band continuum lags in three AGN (NGC 5548, NGC 2617, and MCG+08-11-011, which provide new constraints on the temperature profiles and absolute sizes of the accretion disks. We find lags larger than would be predicted for standard geometrically thin, optically thick accretion disks by factors of 2.3–3.3. For NGC 5548, the data span UV through optical/near-IR wavelengths, and we are able to discern a steeper temperature profile than the T ~ R−3/4 expected for a standard thin disk. Using a physical model, we are also able to estimate the inclinations of the disks for two objects. These results are similar to those found from gravitational microlensing of strongly lensed quasars, and provide a complementary approach for investigating the accretion disk structure in local, low luminosity AGN.

  11. Development of Powered Disk Type Sugar Cane Stubble Saver

    Directory of Open Access Journals (Sweden)

    Radite P.A.S.

    2009-04-01

    Full Text Available The objective of this research was to design, fabricate and test a prototype of sugar cane stubble saver based on powered disk mechanism. In this research, a heavy duty disk plow or disk harrow was used as a rotating knife to cut the sugarcane stubble. The parabolic disk was chosen because it is proven reliable as soil working tools and it is available in the market as spare part of disk plow or disk harrow unit. The prototype was mounted on the four wheel tractor’s three point hitch, and powered by PTO of the tractor. Two kinds of disks were used in these experiments, those were disk with regular edge or plain disk and disk with scalloped edge or scalloped disk. Both disks had diameter of 28 inch. Results of field test showed that powered disk mechanism could satisfy cut sugar cane’s stubble. However, scalloped disk type gave smoother stubble cuts compared to that of plain disk. Plain disk type gave broken stubble cut. Higher rotation (1000 rpm resulted better cuts as compared to lower rotation (500 rpm both either on plain disk and scalloped disk. The developed prototype could work below the soil surface at depth of 5 to 10 cm. With tilt angle setting 20O and disk angle 45O the width of cut was about 25 cm.

  12. Outbursts and Disk Variability in Be Stars

    Science.gov (United States)

    Labadie-Bartz, Jonathan; Chojnowski, S. Drew; Whelan, David G.; Pepper, Joshua; McSwain, M. Virginia; Borges Fernandes, Marcelo; Wisniewski, John P.; Stringfellow, Guy S.; Carciofi, Alex C.; Siverd, Robert J.; Glazier, Amy L.; Anderson, Sophie G.; Caravello, Anthoni J.; Stassun, Keivan G.; Lund, Michael B.; Stevens, Daniel J.; Rodriguez, Joseph E.; James, David J.; Kuhn, Rudolf B.

    2018-02-01

    In order to study the growth and evolution of circumstellar disks around classical Be stars, we analyze optical time-series photometry from the KELT survey with simultaneous infrared and visible spectroscopy from the Apache Point Observatory Galactic Evolution Experiment survey and Be Star Spectra database for a sample of 160 Galactic classical Be stars. The systems studied here show variability including transitions from a diskless to a disk-possessing state (and vice versa), and persistent disks that vary in strength, being replenished at either regularly or irregularly occurring intervals. We detect disk-building events (outbursts) in the light curves of 28% of our sample. Outbursts are more commonly observed in early- (57%), compared to mid- (27%) and late-type (8%) systems. A given system may show anywhere between 0 and 40 individual outbursts in its light curve, with amplitudes ranging up to ∼0.5 mag and event durations between ∼2 and 1000 days. We study how both the photometry and spectroscopy change together during active episodes of disk growth or dissipation, revealing details about the evolution of the circumstellar environment. We demonstrate that photometric activity is linked to changes in the inner disk, and show that, at least in some cases, the disk growth process is asymmetrical. Observational evidence of Be star disks both growing and clearing from the inside out is presented. The duration of disk buildup and dissipation phases are measured for 70 outbursts, and we find that the average outburst takes about twice as long to dissipate as it does to build up in optical photometry. Our analysis hints that dissipation of the inner disk occurs relatively slowly for late-type Be stars.

  13. Extragalactic Thick Disks: Implications for Early Galaxy Evolution

    OpenAIRE

    Dalcanton, Julianne J.; Seth, Anil; Yoachim, Peter

    2005-01-01

    I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low metallicities, long scale lengths, and moderately flattened axial ratios, much like the thick disk of the Milky Way. However, the properties of thick disks change systematically with the mass of the galaxy. The thick disks of low mass galaxies are more prominent and somewhat more metal-poor than those surrounding massiv...

  14. The intervertebral disc contains intrinsic circadian clocks that are regulated by age and cytokines and linked to degeneration.

    Science.gov (United States)

    Dudek, Michal; Yang, Nan; Ruckshanthi, Jayalath Pd; Williams, Jack; Borysiewicz, Elzbieta; Wang, Ping; Adamson, Antony; Li, Jian; Bateman, John F; White, Michael R; Boot-Handford, Raymond P; Hoyland, Judith A; Meng, Qing-Jun

    2017-03-01

    The circadian clocks are internal timing mechanisms that drive ∼24-hour rhythms in a tissue-specific manner. Many aspects of the physiology of the intervertebral disc (IVD) show clear diurnal rhythms. However, it is unknown whether IVD tissue contains functional circadian clocks and if so, how their dysregulation is implicated in IVD degeneration. Clock gene dynamics in ex vivo IVD explants (from PER2:: luciferase (LUC) reporter mice) and human disc cells (transduced with lentivirus containing Per2::luc reporters) were monitored in real time by bioluminescence photon counting and imaging. Temporal gene expression changes were studied by RNAseq and quantitative reverse transcription (qRT)-PCR. IVD pathology was evaluated by histology in a mouse model with tissue-specific deletion of the core clock gene Bmal1. Here we show the existence of the circadian rhythm in mouse IVD tissue and human disc cells. This rhythm is dampened with ageing in mice and can be abolished by treatment with interleukin-1β but not tumour necrosis factor α. Time-series RNAseq revealed 607 genes with 24-hour patterns of expression representing several essential pathways in IVD physiology. Mice with conditional knockout of Bmal1 in their disc cells demonstrated age-related degeneration of IVDs. We have established autonomous circadian clocks in mouse and human IVD cells which respond to age and cytokines, and control key pathways involved in the homeostasis of IVDs. Genetic disruption to the mouse IVD molecular clock predisposes to IVD degeneration. These results support the concept that disruptions to circadian rhythms may be a risk factor for degenerative IVD disease and low back pain. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. A Murine Model for Human ECO Syndrome Reveals a Critical Role of Intestinal Cell Kinase in Skeletal Development.

    Science.gov (United States)

    Ding, Mengmeng; Jin, Li; Xie, Lin; Park, So Hyun; Tong, Yixin; Wu, Di; Chhabra, A Bobby; Fu, Zheng; Li, Xudong

    2017-11-02

    An autosomal-recessive inactivating mutation R272Q in the human intestinal cell kinase (ICK) gene caused profound multiplex developmental defects in human endocrine-cerebro-osteodysplasia (ECO) syndrome. ECO patients exhibited a wide variety of skeletal abnormalities, yet the underlying mechanisms by which ICK regulates skeletal development remained largely unknown. The goal of this study was to understand the structural and mechanistic basis underlying skeletal anomalies caused by ICK dysfunction. Ick R272Q knock-in transgenic mouse model not only recapitulated major ECO skeletal defects such as short limbs and polydactyly but also revealed a deformed spine with defective intervertebral disk. Loss of ICK function markedly reduced mineralization in the spinal column, ribs, and long bones. Ick mutants showed a significant decrease in the proliferation zone of long bones and the number of type X collagen-expressing hypertrophic chondrocytes in the spinal column and the growth plate of long bones. These results implicate that ICK plays an important role in bone and cartilage development by promoting chondrocyte proliferation and maturation. Our findings provided new mechanistic insights into the skeletal phenotype of human ECO and ECO-like syndromes.

  16. WL 17: A Young Embedded Transition Disk

    Science.gov (United States)

    Sheehan, Patrick D.; Eisner, Josh A.

    2017-05-01

    We present the highest spatial resolution ALMA observations to date of the Class I protostar WL 17 in the ρ Ophiuchus L1688 molecular cloud complex, which show that it has a 12 au hole in the center of its disk. We consider whether WL 17 is actually a Class II disk being extincted by foreground material, but find that such models do not provide a good fit to the broadband spectral energy distribution (SED) and also require such high extinction that it would presumably arise from dense material close to the source, such as a remnant envelope. Self-consistent models of a disk embedded in a rotating collapsing envelope can nicely reproduce both the ALMA 3 mm observations and the broadband SED of WL 17. This suggests that WL 17 is a disk in the early stages of its formation, and yet even at this young age the inner disk has been depleted. Although there are multiple pathways for such a hole to be created in a disk, if this hole was produced by the formation of planets it could place constraints on the timescale for the growth of planets in protoplanetary disks.

  17. Numerical simulations of dissipationless disk accretion

    Science.gov (United States)

    Bogovalov, S. V.; Tronin, I. V.

    2017-09-01

    Our goal is to study the regime of disk accretion in which almost all of the angular momentum and energy is carried away by the wind outflowing from the disk in numerical experiments. For this type of accretion the kinetic energy flux in the outflowing wind can exceed considerably the bolometric luminosity of the accretion disk, what is observed in the plasma flow from galactic nuclei in a number of cases. In this paper we consider the nonrelativistic case of an outflow from a cold Keplerian disk. All of the conclusions derived previously for such a system in the self-similar approximation are shown to be correct. The numerical results agree well with the analytical predictions. The inclination angle of the magnetic field lines in the disk is less than 60°, which ensures a free wind outflow from the disk, while the energy flux per wind particle is greater than the particle rotation energy in its Keplerian orbit by several orders of magnitude, provided that the ratio r A/ r ≫ 1, where r A is the Alfvénic radius and r is the radius of the Keplerian orbit. In this case, the particle kinetic energy reaches half the maximum possible energy in the simulation region. The magnetic field collimates the outflowing wind near the rotation axis and decollimates appreciably the wind outflowing from the outer disk periphery.

  18. SPH simulations of structures in protoplanetary disks

    Science.gov (United States)

    Demidova, T. V.; Grinin, V. P.

    2017-02-01

    Using the GADGET-2 code modified by us, we have computed hydrodynamic models of a protoplanetary disk perturbed by a low-mass companion. We have considered the cases of circular and eccentric orbits coplanar with the disk and inclined relative to its midplane. During our simulations we computed the column density of test particles on the line of sight between the central star and observer. On this basis we computed the column density of circumstellar dust by assuming the dust and gas to be well mixed with a mass ratio of 1: 100. To study the influence of the disk orientation relative to the observer on the interstellar extinction, we performed our computations for four inclinations of the line of sight to the disk plane and eight azimuthal directions. The column densities in the circumstellar disk of the central star and the circumbinary disk were computed separately. Our computations have shown that periodic column density oscillations can arise in both inner and circumbinary disks. The amplitude and shape of these oscillations depend on the system's parameters (the orbital eccentricity and inclination, the component mass ratio) and its orientation in space. The results of our simulations can be used to explain the cyclic brightness variations of young UX Ori stars.

  19. Lunar and Meteorite Sample Disk for Educators

    Science.gov (United States)

    Foxworth, Suzanne; Luckey, M.; McInturff, B.; Allen, J.; Kascak, A.

    2015-01-01

    NASA Johnson Space Center (JSC) has the unique responsibility to curate NASA's extraterrestrial samples from past and future missions. Curation includes documentation, preservation, preparation and distribution of samples for research, education and public outreach. Between 1969 and 1972 six Apollo missions brought back 382 kilograms of lunar rocks, core and regolith samples, from the lunar surface. JSC also curates meteorites collected from a US cooperative effort among NASA, the National Science Foundation (NSF) and the Smithsonian Institution that funds expeditions to Antarctica. The meteorites that are collected include rocks from Moon, Mars, and many asteroids including Vesta. The sample disks for educational use include these different samples. Active relevant learning has always been important to teachers and the Lunar and Meteorite Sample Disk Program provides this active style of learning for students and the general public. The Lunar and Meteorite Sample Disks permit students to conduct investigations comparable to actual scientists. The Lunar Sample Disk contains 6 samples; Basalt, Breccia, Highland Regolith, Anorthosite, Mare Regolith and Orange Soil. The Meteorite Sample Disk contains 6 samples; Chondrite L3, Chondrite H5, Carbonaceous Chondrite, Basaltic Achondrite, Iron and Stony-Iron. Teachers are given different activities that adhere to their standards with the disks. During a Sample Disk Certification Workshop, teachers participate in the activities as students gain insight into the history, formation and geologic processes of the moon, asteroids and meteorites.

  20. Latest advances in high brightness disk lasers

    Science.gov (United States)

    Kuhn, Vincent; Gottwald, Tina; Stolzenburg, Christian; Schad, Sven-Silvius; Killi, Alexander; Ryba, Tracey

    2015-02-01

    In the last decade diode pumped solid state lasers have become an important tool for many industrial materials processing applications. They combine ease of operation with efficiency, robustness and low cost. This paper will give insight in latest progress in disk laser technology ranging from kW-class CW-Lasers over frequency converted lasers to ultra-short pulsed lasers. The disk laser enables high beam quality at high average power and at high peak power at the same time. The power from a single disk was scaled from 1 kW around the year 2000 up to more than 10 kW nowadays. Recently was demonstrated more than 4 kW of average power from a single disk close to fundamental mode beam quality (M²=1.38). Coupling of multiple disks in a common resonator results in even higher power. As an example we show 20 kW extracted from two disks of a common resonator. The disk also reduces optical nonlinearities making it ideally suited for short and ultrashort pulsed lasers. In a joint project between TRUMPF and IFSW Stuttgart more than 1.3 kW of average power at ps pulse duration and exceptionally good beam quality was recently demonstrated. The extremely low saturated gain makes the disk laser ideal for internal frequency conversion. We show >1 kW average power and >6 kW peak power in multi ms pulsed regime from an internally frequency doubled disk laser emitting at 515 nm (green). Also external frequency conversion can be done efficiently with ns pulses. >500 W of average UV power was demonstrated.

  1. Regeneration of a spinal ligament after total lumbar disk arthroplasty in primates.

    Science.gov (United States)

    Cunningham, Bryan W; Berven, Sigurd H; Hu, Nianbin; Beatson, Helen J; De Deyne, Patrick G; McAfee, Paul C

    2009-01-01

    Total disk arthroplasty (TDA) is a new procedure that replaces the intervertebral disk space with an artificial motion segment and necessitates the resection of the anterior longitudinal ligament (ALL). We assessed whether a collagen-based graft made from porcine small-intestine submucosa (SIS) can be used as a regenerative scaffold to restore the function and structure of the ALL in the lumbar spine. A total of 10 mature male baboons underwent TDA at L5-L6 using one of two treatments: (1) TDA only (n = 5) or (2) TDA combined with SIS (n = 5). Six months postoperatively, mock revision surgery was performed to assess tissue adhesions followed by non-destructive multidirectional flexibility testing of the spinal segment. The vertebral segments were then processed for histology. The tissue adhesion score was 2.8 +/- 0.8 in the TDA only group and 1.8 +/- 1.4 in the TDA-SIS group (p = 0.2). Segmental range of motion and the length of the neutral zone were similar in both groups. Histology showed that the SIS scaffold led to an organized ligamentous structure with a significantly (p = 0.027) higher thickness (2.18 +/- 0.25 mm) compared to the connective tissue structure in the TDA-only group (1.66 +/- 0.33 mm). We concluded that using a SIS bioscaffold after TDA did not lead to increased great vessel adhesion while its use facilitated the formation of highly organized ligamentous tissues. However, the SIS- induced and newly formed ligamentous tissue anterior to the spinal segment did not lead to a measurable limitation of spinal extension. 2009 S. Karger AG, Basel.

  2. Equilibrium large vortex state in ferromagnetic disks

    Science.gov (United States)

    Metlov, Konstantin L.

    2013-06-01

    Magnetic vortices in soft ferromagnetic nano-disks have been extensively studied for at least several decades both for their applied (non-volatile information storage) as well as fundamental value. Here, it is shown that there is another vortex ground state with large radius-dependent core profile in nano-scale ferromagnetic disks of several exchange lengths in size. Its energy is computed numerically and its stability is studied analytically, which allows to plot it on magnetic phase diagram. Large vortices may exist on par with the classical ones, while being separated by an energy barrier, controllable by tuning the geometry and material of ferromagnetic disk.

  3. Application of a semiautomatic classifier for modic and disk hernia changes in magnetic resonance

    Directory of Open Access Journals (Sweden)

    Eduardo López Arce Vivas

    2015-03-01

    Full Text Available OBJECTIVE: Early detection of degenerative changes in lumbar intervertebral disc by magnetic resonance imaging in a semiautomatic classifier for prevention of degenerative disease. METHOD: MRIs were selected with a diagnosis of degenerative disc disease or back pain from January to May 2014, with a sample of 23 patients and a total of 170 disks evaluated by sagittal T2 MRI image, first evaluated by a specialist physician in training and them were introduced into the software, being the results compared. RESULTS: One hundred and fifteen discs were evaluated by a programmed semiautomatic classifier to identify MODIC changes and hernia, which produced results "normal or MODIC" and "normal or abnormal", respectively. With a total of 230 readings, of which 141 were correct, 84 were reading errors and 10 readings were undiagnosed, the semiautomatic classifier is a useful tool for early diagnosis or established disease and is easy to apply because of the speed and ease of use; however, at this early stage of development, software is inferior to clinical observations and the results were from around 65% to 60% certainty for MODIC rating and 61% to 58% for disc herniation, compared with clinical evaluations. CONCLUSION: The comparative results between the two doctors were 94 consistent results and only 21 errors, which represents 81% certainty.

  4. Does Opioid Pain Medication Use Affect the Outcome of Patients with Lumbar Disk Herniation?

    Science.gov (United States)

    Radcliff, Kris; Freedman, Mitchell; Hilibrand, Alan; Isaac, Roman; Lurie, Jon D.; Zhao, Wenyan; Vaccaro, Alex; Albert, Todd; Weinstein, James

    2013-01-01

    Study Design Subgroup analysis of prospective, randomized cohort Objective To review the results of patients who received opioid pain medications during treatment compared to patients who did not receive opioid medications. Summary of Background Data The SPORT trial is a prospective, multicenter study of surgical treatment versus nonoperative treatment for lumbar intervertebral disk herniation (IDH). Methods The study population includes patients enrolled in SPORT for treatment of IDH in combined randomized and observational cohorts. Patients who received opioid medications at baseline (Opioid) were compared to those who did not. (No-Opioid) Results There were 520 patients in the Non-Opioid group and 542 patients in the Opioid group. Among the opioid medication group there were significantly (popioid medication group with the perception of worsening symptoms and neurological deficit (popioid patients received surgery (popioid and non-opioid medication patients. Opioid medications were associated with increased crossover to surgical treatment (p=0.005) and decreased surgical avoidance. (p=0.01)The incidence of opioid use at four years was 16% among patients who were using opioids at baseline and 5% among patients who were not using opioids at baseline. Conclusion Patients who were treated with opioids had significantly worse baseline pain and quality of life. At final follow-up, there was no long term difference in outcome associated with opioid pain medication use. Opioid medications were not associated with surgical avoidance. The majority of patients who use opioids during the study did not continue usage at four years. PMID:23591657

  5. Accuracy of manual palpation vs ultrasound for identifying the L3-L4 intervertebral space level in children.

    Science.gov (United States)

    Hayes, Jason; Borges, Bruno; Armstrong, Derek; Srinivasan, Ilavajady

    2014-05-01

    Insertion of needles into the spinal or epidural space is an important component of modern anesthetic practice. Needles are usually inserted at or below the L3-L4 intervertebral space to minimize the risk of spinal cord injury. Manual palpation is the most common method for identifying intervertebral spaces. However, anesthesiologists are increasingly using ultrasonography to guide the placement of regional, including neuraxial, anesthetic, and analgesic blocks. We undertook an observational study to compare the accuracy of manual palpation and ultrasound for determining the L3-L4 intervertebral space level. Thirty children 0-12 years of age undergoing lumbar puncture were enrolled. For each subject, an anesthesiologist, using the landmark palpation method, determined the point on a radio-opaque ruler that corresponded to the L3-L4 intervertebral space. A different anesthesiologist using the ultrasound method repeated this measurement. Fluoroscopy was then used to confirm the accuracy of each technique. The proportion of inaccurate measurements and the effects of anesthesiologists' experience, patient age, and size on the accuracy of each technique were compared. Thirty-seven percent of measurements by the landmark palpation method were inaccurate by ≥1 levels cephalad to the L3-L4 intervertebral space. However, less experienced anesthesiologists (residents and fellows) made a disproportionate number of inaccurate measurements compared to consultants. Twenty-three percent of measurements by the ultrasound method were inaccurate by ≥1 cephalad levels. The BMI-for-age percentile/weight-for-length percentile was higher in patients in whom either technique was inaccurate. This observational study found no difference in the accuracy of landmark palpation, when performed by a consultant anesthesiologist, and ultrasound for determining the L3-L4 intervertebral space in children. © 2014 John Wiley & Sons Ltd.

  6. Healing of a painful intervertebral disc should not be confused with reversing disc degeneration: implications for physical therapies for discogenic back pain.

    Science.gov (United States)

    Adams, Michael A; Stefanakis, Manos; Dolan, Patricia

    2010-12-01

    Much is known about intervertebral disc degeneration, but little effort has been made to relate this information to the clinical problem of discogenic back pain, and how it might be treated. We re-interpret the scientific literature in order to provide a rationale for physical therapy treatments for discogenic back pain. Intervertebral discs deteriorate over many years, from the nucleus outwards, to an extent that is influenced by genetic inheritance and metabolite transport. Age-related deterioration can be accelerated by physical disruption, which leads to disc "degeneration" or prolapse. Degeneration most often affects the lower lumbar discs, which are loaded most severely, and it is often painful because nerves in the peripheral anulus or vertebral endplate can be sensitised by inflammatory-like changes arising from contact with blood or displaced nucleus pulposus. Surgically-removed human discs show an active inflammatory process proceeding from the outside-in, and animal studies confirm that effective healing occurs only in the outer anulus and endplate, where cell density and metabolite transport are greatest. Healing of the disc periphery has the potential to relieve discogenic pain, by re-establishing a physical barrier between nucleus pulposus and nerves, and reducing inflammation. Physical therapies should aim to promote healing in the disc periphery, by stimulating cells, boosting metabolite transport, and preventing adhesions and re-injury. Such an approach has the potential to accelerate pain relief in the disc periphery, even if it fails to reverse age-related degenerative changes in the nucleus. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. Effects of torsion on intervertebral disc gene expression and biomechanics, using a rat tail model.

    Science.gov (United States)

    Barbir, Ana; Godburn, Karolyn E; Michalek, Arthur J; Lai, Alon; Monsey, Robert D; Iatridis, James C

    2011-04-15

    In vitro and in vivo rat tail model to assess effects of torsion on intervertebral disc biomechanics and gene expression. Investigate effects of torsion on promoting biosynthesis and producing injury in rat caudal intervertebral discs. Torsion is an important loading mode in the disc and increased torsional range of motion is associated with clinical symptoms from disc disruption. Altered elastin content is implicated in disc degeneration, but its effects on torsional loading are unknown. Although effects of compression have been studied, the effect of torsion on intervertebral disc gene expression is unknown. In vitro biomechanical tests were performed in torsion on rat tail motion segments subjected to 4 treatments: elastase, collagenase, genipin, control. In vivo tests were performed on rats with Ilizarov-type fixators implanted to caudal motion segments with five 90 minute loading groups: 1 Hz cyclic torsion to ± 5 ± 15° and ± 30°, static torsion to + 30°, and sham. Anulus and nucleus tissues were separately analyzed using qRT-PCR for gene expression of anabolic, catabolic, and proinflammatory cytokine markers. In vitro tests showed decreased torsional stiffness following elastase treatment and no changes in stiffness with frequency. In vivo tests showed no significant changes in dynamic stiffness with time. Cyclic torsion upregulated elastin expression in the anulus fibrosus. Up regulation of TNF-α and IL-1β was measured at ±30°. We conclude that strong differences in the disc response to cyclic torsion and compression are apparent with torsion increasing elastin expression and compression resulting in a more substantial increase in disc metabolism in the nucleus pulposus. Results highlight the importance of elastin in torsional loading and suggest that elastin remodels in response to shearing. Torsional loading can cause injury to the disc at excessive amplitudes that are detectable biologically before they are biomechanically.

  8. CT and MRI Determination of Intermuscular Space within Lumbar Paraspinal Muscles at Different Intervertebral Disc Levels

    Science.gov (United States)

    Wang, Shidong; Zhang, Yu; Han, Hui; Zheng, Dengquan; Ding, Zihai; Wong, Kelvin K. L.

    2015-01-01

    Background Recognition of the intermuscular spaces within lumbar paraspinal muscles is critically important for using the paramedian muscle-splitting approach to the lumbar spine. As such, it is important to determine the intermuscular spaces within the lumbar paraspinal muscles by utilizing modern medical imaging such as computed tomography (CT) and magnetic resonance imaging (MRI). Methods A total of 30 adult cadavers were studied by sectional anatomic dissection, and 60 patients were examined using CT (16 slices, 3-mm thickness, 3-mm intersection gap, n = 30) and MRI (3.0T, T2-WI, 5-mm thickness, 1-mm intersection gap, n = 30). The distances between the midline and the superficial points of the intermuscular spaces at different intervertebral disc levels were measured. Results Based on study of our cadavers, the mean distances from the midline to the intermuscular space between multifidus and longissimus, from intervertebral disc levels L1–L2 to L5–S1, were 0.9, 1.1, 1.7, 3.0, and 3.5 cm, respectively. Compared with the upper levels (L1–L3), the superficial location at the lower level (L4–S1) is more laterally to the midline (Pspine showing a low discontinuous density in CT and a high signal in MRI. There were no significant differences between the observations in cadavers and those made using CT and MRI. Conclusion The intermuscular spaces within the paraspinal muscles vary at different intervertebral disc levels. Preoperative CT and MRI can facilitate selection of the muscle-splitting approach to the lumbar spine. This paper demonstrates the efficacy of medical imaging techniques in surgical planning. PMID:26458269

  9. Prevalence and breed predisposition for thoracolumbar intervertebral disc disease in cats.

    Science.gov (United States)

    De Decker, Steven; Warner, Anne-Sophie; Volk, Holger A

    2017-04-01

    Objectives The objective was to evaluate the prevalence and possible breed predilections for thoracolumbar intervertebral disc disease (IVDD) in cats. Methods Medical records and imaging studies of cats diagnosed with thoracolumbar IVDD between January 2008 and August 2014 were retrospectively reviewed and compared with the general hospital population. The association between type of IVDD (ie, intervertebral disc extrusion [IVDE] or intervertebral disc protrusion [IVDP]) and breed, age, sex, and duration and severity of clinical signs was also evaluated. Results Of 12,900 cats presented during the study period, 31 (0.24%) were diagnosed with IVDD, including 17 purebred and 14 non-purebred cats. Of all presented purebred cats, 0.52% were diagnosed with thoracolumbar IVDD. More specifically, 1.29% of all British Shorthairs and 1.83% of all presented Persians were diagnosed with IVDD. Compared with the general hospital population, purebred cats ( P = 0.0001), British Shorthairs ( P cats were younger than affected non-purebred cats ( P = 0.02). Of 31 cats with IVDD, 19 were diagnosed with IVDE and 12 with IVDP. Cats with IVDE had a significantly shorter duration of clinical signs ( P = 0.0002) and demonstrated more severe neurological deficits ( P = 0.04) than cats with IVDP. Conclusions and relevance Although thoracolumbar IVDD is an uncommon condition in cats, purebred cats, British Shorthairs and Persians, were overrepresented. It is currently unclear if this represents a true breed predisposition or a higher likelihood of owners of purebred cats seeking referral for advanced diagnostic imaging procedures.

  10. CT and MRI Determination of Intermuscular Space within Lumbar Paraspinal Muscles at Different Intervertebral Disc Levels.

    Directory of Open Access Journals (Sweden)

    Xuefei Deng

    Full Text Available Recognition of the intermuscular spaces within lumbar paraspinal muscles is critically important for using the paramedian muscle-splitting approach to the lumbar spine. As such, it is important to determine the intermuscular spaces within the lumbar paraspinal muscles by utilizing modern medical imaging such as computed tomography (CT and magnetic resonance imaging (MRI.A total of 30 adult cadavers were studied by sectional anatomic dissection, and 60 patients were examined using CT (16 slices, 3-mm thickness, 3-mm intersection gap, n = 30 and MRI (3.0T, T2-WI, 5-mm thickness, 1-mm intersection gap, n = 30. The distances between the midline and the superficial points of the intermuscular spaces at different intervertebral disc levels were measured.Based on study of our cadavers, the mean distances from the midline to the intermuscular space between multifidus and longissimus, from intervertebral disc levels L1-L2 to L5-S1, were 0.9, 1.1, 1.7, 3.0, and 3.5 cm, respectively. Compared with the upper levels (L1-L3, the superficial location at the lower level (L4-S1 is more laterally to the midline (P<0.05. The intermuscular space between sacrospinalis and quadratus lumborum, and that between longissimus and iliocostalis did not exist at L4-S1. The intermuscular spaces in patients also varied at different levels of the lumbar spine showing a low discontinuous density in CT and a high signal in MRI. There were no significant differences between the observations in cadavers and those made using CT and MRI.The intermuscular spaces within the paraspinal muscles vary at different intervertebral disc levels. Preoperative CT and MRI can facilitate selection of the muscle-splitting approach to the lumbar spine. This paper demonstrates the efficacy of medical imaging techniques in surgical planning.

  11. LASER BIOLOGY AND MEDICINE: Effect of repetitive laser pulses on the electrical conductivity of intervertebral disc tissue

    Science.gov (United States)

    Omel'chenko, A. I.; Sobol', E. N.

    2009-03-01

    The thermomechanical effect of 1.56-μm fibre laser pulses on intervertebral disc cartilage has been studied using ac conductivity measurements with coaxial electrodes integrated with an optical fibre for laser radiation delivery to the tissue. The observed time dependences of tissue conductivity can be interpreted in terms of hydraulic effects and thermomechanical changes in tissue structure. The laserinduced changes in the electrical parameters of the tissue are shown to correlate with the structural changes, which were visualised using shadowgraph imaging. Local ac conductivity measurements in the bulk of tissue can be used to develop a diagnostic/monitoring system for laser regeneration of intervertebral discs.

  12. 1980 Volvo award winner in basic science. Nutritional pathways of the intervertebral disc. An experimental study using hydrogen washout technique.

    Science.gov (United States)

    Ogata, K; Whiteside, L A

    1981-01-01

    The pathways of material transfer to the intervertebral disc were studied in adult dogs by measuring diffusion of hydrogen molecules in the nucleus pulposus before and after disruption of the route through the annulus fibrosus and before and after disruption of the end-plate route. The interfaces was only in the central two-thirds of one side, caused significantly greater decrease in the rate of hydrogen washout than the disruption of the annulus route. Histologically, the bone-cartilage interface was frequently perforated by marrow cavity and vascular buds. These findings suggest that the end-plate route is a major pathway for material transfer to the intervertebral disc.

  13. Clinical efficacy of bone cement injectable pedicle screw system combined with intervertebral fusion in treatment of lumbar spondylolysis and osteoporosis

    Directory of Open Access Journals (Sweden)

    Peng-yi DAI

    2016-10-01

    Full Text Available Objective  To observe the therapeutic effect of bone cement injectable pedicle screw system combined with intervertebral fusion for lumbar spondylolysis and osteoporosis. Methods  The clinical data were analyzed retrospectively of 21 patients with lumbar spondylolysis and osteoporosis who received treatment of bone cement injectable pedicle screw system and intervertebral fusion from Aug. 2013 to Nov. 2015. The 21 patients (9 males and 12 females aged from 60 to 80 years (mean 64 years old; 6 of them presented degenerative spondylolysis, 15 with isthmic spondylolisthesis; 2 cases had I degree slippage, 13 had Ⅱdegree slippage, 6 had Ⅲdegree slippage, and all the cases were unisegmental slippage including 9 cases in L4 and 12 cases in L5. Bone mineral density of lumbar vertebrae (L2-L5 was measured with dual-energy X-ray absorptiometry, and T values conforming to the diagnostic criteria of osteoporosis were less than or equal to -2.5; All patients were operated with whole lamina resection for decompression, bone cement injectable pedicle screws system implantation, propped open reduction and fixation intervertebral fusion. The clinical outcomes were determined by the radiographic evaluation including intervertebral height, height of intervertebral foramen, slip distance, slip rate and slip angle, and Oswestry disability index (ODI on preoperative, 3 months after operation and the end of the time, and the interbody fusion were followed up. Results  Cerebrospinal fluid leakage of incision was observed in two cases after operation, compression and dressing to incision, Trendelenburg position, dehydration and other treatments were taken, and the stitches of incisions were taken out on schedule. Slips in the 21 patients were reset to different extent, and lumbar physiological curvatures were recovered. The intervertebral height and height of intervertebral foramen were obviously higher 3 months after operation than that before operation (P0

  14. [Observation on therapeutic effect of acupuncture and moxibustion combined with sacral injection on prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Liu, Yi-jun; Zhou, You-long

    2005-02-01

    To search for an effective method for treatment of prolapse of lumbar intervertebral disc. Ninety-four cases were randomly divided into a treatment group of 48 cases and a control group of 46 cases. The treatment group were treated by acupuncture and moxibustion combined with sacral injection and the control group with simple sacral injection. Their therapeutic effects were compared. The cured and total effective rates were 64.6% and 97.9% in the treatment group, and 37.0% and 89.1% in the control group, with statistically significant differences between the two groups (both P prolapse of lumbar intervertebral disc.

  15. Expression of NG2 proteoglycan in the degenerated intervertebral disc in dachshunds.

    Science.gov (United States)

    Abdel-Hakiem, Mohammed; Yamashita, Ayuko; Atiba, Ayman; Okamura, Yasuhiko; Katayama, Masaaki; Youssef, Haroun; Isomura, Hiroshi; Uzuka, Yuji

    2016-01-01

    The pathogenesis of intervertebral disc (IVD) degeneration is not fully understood. The biomolecular signaling pathways involved in the IVD degeneration require further investigation. The aim of this study was to investigate the expression of NG2 proteoglycan in the degenerated IVD. IVD samples were obtained from 16 Dachshunds that were confirmed to have IVD herniation and subsequently underwent hemilaminectomy. The samples were subjected to histological and immunohistochemical (IHC) examinations. IHC revealed positive results for the expression of NG2 proteoglycan in all examined samples. The results showed the expression of NG2 proteoglycan by the degenerated IVDs.

  16. Successful medical management of lumbar intervertebral disc prolapse in a ferret.

    Science.gov (United States)

    Srugo, I; Chai, O; Yaakov, D; Sharon, L; Shamir, M H

    2010-08-01

    Thoracolumbar disc herniation was diagnosed in a two-year-old ferret using a myelogram followed by a computed tomography scan. The ferret was paraplegic with no control over urination and defecation. Conservative treatment that included cage rest and passive range of motion exercises for three weeks followed by extensive physiotherapy and hydrotherapy resulted in full recovery two months after the onset of treatment. Although intervertebral disc disease has been reported previously in four ferrets, this is the first report in which a postmyelogram computed tomography was used to demonstrate the herniated disc, and physiotherapy was used as principal treatment modality.

  17. Disk MHD Conversion System for Nerva Reactor

    National Research Council Canada - National Science Library

    Jackson, W

    1992-01-01

    The principal results of the study have been to: (1) confirm that cesium seeded hydrogen plasma disk MHD generator can meet its expected performance while operating in a stable plasma regime; and (2...

  18. Foundations of Black Hole Accretion Disk Theory

    National Research Council Canada - National Science Library

    Abramowicz, Marek A; Fragile, P. Chris

    2013-01-01

    This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves...

  19. Exact Relativistic Magnetized Haloes around Rotating Disks

    Directory of Open Access Journals (Sweden)

    Antonio C. Gutiérrez-Piñeres

    2015-01-01

    Full Text Available The study of the dynamics of magnetic fields in galaxies is one of important problems in formation and evolution of galaxies. In this paper, we present the exact relativistic treatment of a rotating disk surrounded by a magnetized material halo. The features of the halo and disk are described by the distributional energy-momentum tensor of a general fluid in canonical form. All the relevant quantities and the metric and electromagnetic potentials are exactly determined by an arbitrary harmonic function only. For instance, the generalized Kuzmin-disk potential is used. The particular class of solutions obtained is asymptotically flat and satisfies all the energy conditions. Moreover, the motion of a charged particle on the halo is described. As far as we know, this is the first relativistic model describing analytically the magnetized halo of a rotating disk.

  20. Internal and external resonances of dielectric disks

    NARCIS (Netherlands)

    Dettmann, C. P.; Morozov, G. V.; Sieber, M.; Waalkens, H.

    Circular microresonators (microdisks) are micron size dielectric disks embedded in a material of lower refractive index. They possess modes with complex eigenvalues (resonances) which are solutions of analytically given transcendental equations. The behavior of such eigenvalues in the small opening

  1. ON THE TRANSITIONAL DISK CLASS: LINKING OBSERVATIONS OF T TAURI STARS AND PHYSICAL DISK MODELS

    Energy Technology Data Exchange (ETDEWEB)

    Espaillat, C.; Andrews, S.; Qi, C.; Wilner, D. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-78, Cambridge, MA 02138 (United States); Ingleby, L.; Calvet, N. [Department of Astronomy, University of Michigan, 830 Dennison Building, 500 Church Street, Ann Arbor, MI 48109 (United States); Hernandez, J. [Centro de Investigaciones de Astronomia (CIDA), Merida 5101-A (Venezuela, Bolivarian Republic of); Furlan, E. [National Optical Astronomy Observatory, 950 N. Cherry Ave., Tucson, AZ 85719 (United States); D' Alessio, P. [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, 58089 Morelia, Michoacan (Mexico); Muzerolle, J., E-mail: cespaillat@cfa.harvard.edu, E-mail: sandrews@cfa.harvard.edu, E-mail: cqi@cfa.harvard.edu, E-mail: dwilner@cfa.harvard.edu, E-mail: lingleby@umich.edu, E-mail: ncalvet@umich.edu, E-mail: jesush@cida.ve, E-mail: Elise.Furlan@jpl.nasa.gov, E-mail: p.dalessio@crya.unam.mx, E-mail: muzerol@stsci.edu [Space Telescope Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2012-03-10

    Two decades ago 'transitional disks' (TDs) described spectral energy distributions (SEDs) of T Tauri stars with small near-IR excesses, but significant mid- and far-IR excesses. Many inferred this indicated dust-free holes in disks possibly cleared by planets. Recently, this term has been applied disparately to objects whose Spitzer SEDs diverge from the expectations for a typical full disk (FD). Here, we use irradiated accretion disk models to fit the SEDs of 15 such disks in NGC 2068 and IC 348. One group has a 'dip' in infrared emission while the others' continuum emission decreases steadily at all wavelengths. We find that the former have an inner disk hole or gap at intermediate radii in the disk and we call these objects 'transitional disks' and 'pre-transitional disks' (PTDs), respectively. For the latter group, we can fit these SEDs with FD models and find that millimeter data are necessary to break the degeneracy between dust settling and disk mass. We suggest that the term 'transitional' only be applied to objects that display evidence for a radical change in the disk's radial structure. Using this definition, we find that TDs and PTDs tend to have lower mass accretion rates than FDs and that TDs have lower accretion rates than PTDs. These reduced accretion rates onto the star could be linked to forming planets. Future observations of TDs and PTDs will allow us to better quantify the signatures of planet formation in young disks.

  2. LMC Microlensing and Very Thick Disks

    OpenAIRE

    Gyuk, Geza; Gates, Evalyn

    1998-01-01

    We investigate the implications of a very thick (scale height 1.5 - 3.0 kpc) disk population of MACHOs. Such a population represents a reasonable alternative to standard halo configurations of a lensing population. We find that very thick disk distributions can lower the lens mass estimate derived from the microlensing data toward the LMC, although an average lens mass substantially below $0.3\\Msol$ is unlikely. Constraints from direct searches for such lenses imply very low luminosity object...

  3. Dissecting disks around B-type protostars

    Science.gov (United States)

    Sanchez-Monge, Alvaro; Cesaroni, Riccardo; Beltran, Maite; Kumar, M. S. Nanda; Stanke, Thomas; Zinnecker, Hans; Etoka, Sandra; Galli, Daniele; Hummel, Christian A.; Moscadelli, Luca; Preibisch, Thomas; Ratzka, Thorsten; van der Tak, Floris F. S.; Vig, Sarita; Walmsley, C. Malcolm; Wang, Kuo-Song

    2013-07-01

    Recent theoretical models indicate that OB-type stars could form through disk-mediated accretion, like their low mass counterparts. However, on the observational side, circumstellar disks appear still elusive, especially around the most massive (proto)stars. As for early B-type (proto)stars, an ever growing number of disk candidates has been proposed, but only very few of these present evidence for Keplerian rotation. The advent of ALMA provides us with the necessary sensitivity and angular resolution to assess the existence of such disks and possibly establish their rotation curves. With this in mind, we have performed ALMA observations with the highest possible resolution (~0.4") at 350 GHz to search for circumstellar disks in a couple of presumably massive young stellar objects with luminosities of ~10000 Lsun and associated with bipolar nebulosities suggestive of the presence of disk/outflow systems. By observing simultaneously core and jet tracers, we could reveal molecular cores with velocity gradients perpendicular to the corresponding jets. In at least one case (G35.20-0.74 N), the core structure appears resolved and the velocity field can be fitted with an almost edge-on Keplerian disk rotating about a central mass of 18 Msun. This finding is consistent with the results of a recent study of the CO first overtone bandhead emission at 2.3mum towards G35.20-0.74 N. The disk radius and mass are >2500 au and 3 Msun. To reconcile the observed bolometric luminosity (3x10^4 Lsun) with the estimated stellar mass of 18 Msun, we propose that the latter is the total mass of a binary system.

  4. YottaYotta announces new world record set for TCP disk-to-disk bulk transfer

    CERN Multimedia

    2002-01-01

    The Yottabyte NetStorage(TM) Company, today announced a new world record for TCP disk-to-disk data transfer using the company's NetStorager(R) System. The record-breaking demonstration transferred 5 terabytes of data between Chicago, Il. to Vancouver, BC and Ottawa, ON, at a sustained average throughput of 11.1 gigabits per second. Peak throughput exceeded 11.6 gigabits per second, more than 15-times faster than previous records for TCP transfer from disk-to-disk (1 page).

  5. Empirical Temperature Measurement in Protoplanetary Disks

    Science.gov (United States)

    Weaver, Erik; Isella, Andrea; Boehler, Yann

    2018-02-01

    The accurate measurement of temperature in protoplanetary disks is critical to understanding many key features of disk evolution and planet formation, from disk chemistry and dynamics, to planetesimal formation. This paper explores the techniques available to determine temperatures from observations of single, optically thick molecular emission lines. Specific attention is given to issues such as the inclusion of optically thin emission, problems resulting from continuum subtraction, and complications of real observations. Effort is also made to detail the exact nature and morphology of the region emitting a given line. To properly study and quantify these effects, this paper considers a range of disk models, from simple pedagogical models to very detailed models including full radiative transfer. Finally, we show how the use of the wrong methods can lead to potentially severe misinterpretations of data, leading to incorrect measurements of disk temperature profiles. We show that the best way to estimate the temperature of emitting gas is to analyze the line peak emission map without subtracting continuum emission. Continuum subtraction, which is commonly applied to observations of line emission, systematically leads to underestimation of the gas temperature. We further show that once observational effects such as beam dilution and noise are accounted for, the line brightness temperature derived from the peak emission is reliably within 10%–15% of the physical temperature of the emitting region, assuming optically thick emission. The methodology described in this paper will be applied in future works to constrain the temperature, and related physical quantities, in protoplanetary disks observed with ALMA.

  6. Rhodopsin mutant P23H destabilizes rod photoreceptor disk membranes.

    Directory of Open Access Journals (Sweden)

    Mohammad Haeri

    Full Text Available Mutations in rhodopsin cause retinitis pigmentosa in humans and retinal degeneration in a multitude of other animals. We utilized high-resolution live imaging of the large rod photoreceptors from transgenic frogs (Xenopus to compare the properties of fluorescently tagged rhodopsin, Rho-EGFP, and Rho(P23H-EGFP. The mutant was abnormally distributed both in the inner and outer segments (OS, accumulating in the OS to a concentration of ∼0.1% compared to endogenous opsin. Rho(P23H-EGFP formed dense fluorescent foci, with concentrations of mutant protein up to ten times higher than other regions. Wild-type transgenic Rho-EGFP did not concentrate in OS foci when co-expressed in the same rod with Rho(P23H-EGFP. Outer segment regions containing fluorescent foci were refractory to fluorescence recovery after photobleaching, while foci in the inner segment exhibited recovery kinetics similar to OS regions without foci and Rho-EGFP. The Rho(P23H-EGFP foci were often in older, more distal OS disks. Electron micrographs of OS revealed abnormal disk membranes, with the regular disk bilayers broken into vesiculotubular structures. Furthermore, we observed similar OS disturbances in transgenic mice expressing Rho(P23H, suggesting such structures are a general consequence of mutant expression. Together these results show that mutant opsin disrupts OS disks, destabilizing the outer segment possibly via the formation of aggregates. This may render rods susceptible to mechanical injury or compromise OS function, contributing to photoreceptor loss.

  7. THE SPITZER INFRARED SPECTROGRAPH SURVEY OF PROTOPLANETARY DISKS IN ORION A. I. DISK PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K. H. [Korea Astronomy and Space Science Institute (KASI), 776, Daedeokdae-ro, Yuseong-gu, Daejeon 305-348 (Korea, Republic of); Watson, Dan M.; Manoj, P.; Forrest, W. J. [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States); Furlan, Elise [Infrared Processing and Analysis Center, Caltech, 770 S. Wilson Avenue, Pasadena, CA 91125 (United States); Najita, Joan [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Sargent, Benjamin [Center for Imaging Science and Laboratory for Multiwavelength Astrophysics, Rochester Institute of Technology, 54 Lomb Memorial Dr., Rochester, NY 14623 (United States); Hernández, Jesús [Centro de Investigaciones de Astronomía, Apdo. Postal 264, Mérida 5101-A (Venezuela, Bolivarian Republic of); Calvet, Nuria [Department of Astronomy, University of Michigan, 830 Dennison Building, 500 Church Street, Ann Arbor, MI 48109 (United States); Adame, Lucía [Facultad de Ciencias Físico-Matemáticas, Universidad Autónoma de Nuevo León, Av. Universidad S/N, San Nicolás de los Garza, Nuevo León, C.P. 66451, México (Mexico); Espaillat, Catherine [Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States); Megeath, S. T. [Ritter Astrophysical Research Center, Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft St., Toledo, OH 43606 (United States); Muzerolle, James, E-mail: quarkosmos@kasi.re.kr [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); and others

    2016-09-01

    We present our investigation of 319 Class II objects in Orion A observed by Spitzer /IRS. We also present the follow-up observations of 120 of these Class II objects in Orion A from the Infrared Telescope Facility/SpeX. We measure continuum spectral indices, equivalent widths, and integrated fluxes that pertain to disk structure and dust composition from IRS spectra of Class II objects in Orion A. We estimate mass accretion rates using hydrogen recombination lines in the SpeX spectra of our targets. Utilizing these properties, we compare the distributions of the disk and dust properties of Orion A disks with those of Taurus disks with respect to position within Orion A (Orion Nebular Cluster [ONC] and L1641) and with the subgroups by the inferred radial structures, such as transitional disks (TDs) versus radially continuous full disks (FDs). Our main findings are as follows. (1) Inner disks evolve faster than the outer disks. (2) The mass accretion rates of TDs and those of radially continuous FDs are statistically significantly displaced from each other. The median mass accretion rate of radially continuous disks in the ONC and L1641 is not very different from that in Taurus. (3) Less grain processing has occurred in the disks in the ONC compared to those in Taurus, based on analysis of the shape index of the 10 μ m silicate feature ( F {sub 11.3}/ F {sub 9.8}). (4) The 20–31 μ m continuum spectral index tracks the projected distance from the most luminous Trapezium star, θ {sup 1} Ori C. A possible explanation is UV ablation of the outer parts of disks.

  8. Apparent diffusion coefficient in normal and abnormal pattern of intervertebral lumbar discs: initial experience☆

    Science.gov (United States)

    Niu, Gang; Yu, Xuewen; Yang, Jian; Wang, Rong; Zhang, Shaojuan; Guo, Youmin

    2011-01-01

    The aim of the present study was to compare the relationship of morphologically defined non-bulging/herniated, bulging and herniated intervertebral lumbar discs with quantitative apparent diffusion coefficient (ADC). Thirty-two healthy volunteers and 28 patients with back pain or sciatica were examined by MRI. All intervertebral lumbar discs from L1 to S1 were classified according to morphological abnormality and degenerated grades. The ADC values of nucleus pulposus (NP) were measured and recorded. The significant differences about mean ADC values of NP were found between non-bulging/herniated discs and bulging discs as well as herniated discs (P herniated discs (P > 0.05). Moreover, statistically significant relationship was found in the mean ADC values of NP between “non-bulging/herniated and non-degenerated discs” and “non-bulging/herniated degenerated discs” as well as herniated discs (P disc level revealed an inverse correlation (r = -0.18). The ADC map of the NP is a potentially useful tool for the quantitative assessment of componential and molecular alterations accompanied with lumbar disc abnormalities. PMID:23554690

  9. Towards an affordable deep learning system: automated intervertebral disc detection in x-ray images

    Science.gov (United States)

    Sa, Ruhan; Owens, William; Wiegand, Raymond; Chaudhary, Vipin

    2017-03-01

    Adult Spinal Deformity is a prominent medical issue with about 68% of the elderly population suffering from the disease.1 Detailed biomechanical assessment is needed both in the presurgical planning of structural spinal deformity as well as in early functional biomechanical compensation in ambulatory spinal pain patients. When considering automation of this process, we have to look at photographic intervertebral disc detection technique as a way to produce a detailed model of the spine with appropriate measurements required to make efficient and accurate decisions on patient care. Deep convolutional neural network (CNN) has given remarkable results in object recognition tasks in recent years. However, massive training data, computational resources and long training time is needed for both training a deep network from scratch or finetuning a network. Using pretrained model as feature extractor has shown promising result for moderate sized medical data.2 However, most work have extracted features from the last layer and little has been explored in terms of the number of convolutional layers needed for best performance. In this work we trained Support Vector Machine (SVM) classifiers on different layers of CaffeNet3 features to show that deeper the better concept does not hold for task such as intervertebral disc detection. Furthermore, our experimental results show the potential of using very small training data, such as 15 annotated medical images in our experiment, to yield satisfactory classification performance with accuracy up to 97.2%.

  10. Polyetheretherketone (PEEK) intervertebral cage as a cause of chronic systemic allergy: a case report.

    Science.gov (United States)

    Maldonado-Naranjo, Andres L; Healy, Andrew T; Kalfas, Iain H

    2015-07-01

    Polyetheretherketone (PEEK) is an organic polymer thermoplastic with strong mechanical and chemical resistance properties. It has been used in industry to fabricate items for demanding applications such as bearings, piston parts, compressor plate valves, and cable insulation. Since the early 1980s, polyetheretherketone polymers have been increasingly used in orthopedic and spinal surgery applications. Numerous studies and years of clinical experience have confirmed the biocompatibility of this material. The purpose of the study was to report a case of chronic systemic allergy after anterior cervical decompression and fusion (ACDF) and implantation of an intervertebral PEEK cage, with resolution of symptoms after removal of PEEK cage. This study is a case report with clinical evidence for allergy to PEEK. The methods involve clinical findings and review of current literature. After ACDF and implantation of an intervertebral PEEK cage, the patient had developed an angioedema-like picture marked by severe redness, itching, swelling of his tongue, and skin thickening. A skin patch test was positive for PEEK. Removal of the implant resulted in the resolution of his allergy symptoms shortly after surgery. Tissue reactions to PEEK are extremely rare. Herein, we present the first report of a chronic allergic response to interbody PEEK material. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Quantifying the effect of intervertebral cartilage on neutral posture in the necks of sauropod dinosaurs.

    Science.gov (United States)

    Taylor, Michael P

    2014-01-01

    Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises) the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the cartilage thickness divided by the height of the zygapophyseal facets over the centre of rotation. Applying this formula to published measurements of well-known sauropod specimens suggests that if the thickness of cartilage were equal to 4.5%, 10% or 18% of centrum length, the neutral pose of the Apatosaurus louisae holotype CM 3018 would be extended by an average of 5.5, 11.8 or 21.2 degrees, respectively, at each intervertebral joint. For the Diplodocus carnegii holotype CM 84, the corresponding angles of additional extension are even greater: 8.4, 18.6 or 33.3 degrees. The cartilaginous neutral postures (CNPs) calculated for 10% cartilage-the most reasonable estimate-appear outlandish. But it must be remembered that these would not have been the habitual life postures, because tetrapods habitually extend the base of their neck and flex the anterior part, yielding the distinctive S-curve most easily seen in birds.

  12. Quantifying the effect of intervertebral cartilage on neutral posture in the necks of sauropod dinosaurs

    Directory of Open Access Journals (Sweden)

    Michael P. Taylor

    2014-12-01

    Full Text Available Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the cartilage thickness divided by the height of the zygapophyseal facets over the centre of rotation. Applying this formula to published measurements of well-known sauropod specimens suggests that if the thickness of cartilage were equal to 4.5%, 10% or 18% of centrum length, the neutral pose of the Apatosaurus louisae holotype CM 3018 would be extended by an average of 5.5, 11.8 or 21.2 degrees, respectively, at each intervertebral joint. For the Diplodocus carnegii holotype CM 84, the corresponding angles of additional extension are even greater: 8.4, 18.6 or 33.3 degrees. The cartilaginous neutral postures (CNPs calculated for 10% cartilage—the most reasonable estimate—appear outlandish. But it must be remembered that these would not have been the habitual life postures, because tetrapods habitually extend the base of their neck and flex the anterior part, yielding the distinctive S-curve most easily seen in birds.

  13. Low Intensity Pulsed Ultrasound (LIPUS) for the treatment of intervertebral disc degeneration

    Science.gov (United States)

    Horne, Devante; Jones, Peter; Salgaonkar, Vasant; Adams, Matt; Ozilgen, B. Arda; Zahos, Peter; Tang, Xinyan; Liebenberg, Ellen; Coughlin, Dezba; Lotz, Jeffrey; Diederich, Chris

    2017-02-01

    Discogenic back pain presents a major public health issue, with current therapeutic interventions limited to short-term symptom relief without providing regenerative remedies for diseased intervertebral discs (IVD). Many of these interventions are invasive and can diminish the biomechanical integrity of the IVDs. Low intensity pulsed ultrasound (LIPUS) is a potential treatment option that is both non-invasive and regenerative. LIPUS has been shown to be a clinically effective method for the enhancement of wound and fracture healing. Recent in vitro studies have shown that LIPUS stimulation induces an upregulation functional matrix proteins and downregulation of inflammatory factors in cultured IVD cells. However, we do not know the effects of LIPUS on an in vivo model for intervertebral disc degeneration. The objective of this study was to show technical feasibility of building a LIPUS system that can target the rat tail IVD and apply this setup to a model for acute IVD degeneration. A LIPUS exposimetry system was built using a 1.0 MHz planar transducer and custom housing. Ex vivo intensity measurements demonstrated LIPUS delivery to the center of the rat tail IVD. Using an established stab-incision model for disc degeneration, LIPUS was applied for 20 minutes daily for five days. For rats that displayed a significant injury response, LIPUS treatment caused significant upregulation of Collagen II and downregulation of Tumor Necrosis Factor - α gene expression. Our preliminary studies indicate technical feasibility of targeted delivery of ultrasound to a rat tail IVD for studies of LIPUS biological effects.

  14. Strategies for replicating anatomical cartilaginous tissue gradient in engineered intervertebral disc.

    Science.gov (United States)

    Bhattacharjee, Maumita; Chameettachal, Shibu; Pahwa, Shikha; Ray, Alok R; Ghosh, Sourabh

    2014-01-08

    A critical challenge in fabricating a load bearing tissue, such as an intervertebral disc, is to simulate cellular and matrix alignment and anisotropy, as well as a specific biochemical gradient. Towards this goal, multilamellar silk fibroin scaffolds having criss-cross fibrous orientation were developed, where silk fibers in inner layers were crosslinked with bioactive molecule chondroitin sulfate. Upon culturing goat articular chondrocytes under static and dynamic conditions, lamellar scaffold architecture guided alignment of cells and the newly synthesized extracellular matrix (ECM) along the silk fibers. The dynamic culture conditions further improved the cellular metabolic rate and ECM production. Further the synergistic effect of chemical composition of scaffold and hydrodynamic environment of bioreactor contributed in developing a tissue gradient within the constructs, with an inner region rich in collagen II, glycosaminoglycan (GAG), and stiffer in compression, whereas an outer region rich in collagen I and stiffer in tension. Therefore, a unique combination of chemical and physical parameters of engineered constructs and dynamic culture conditions provides a promising starting point to further improve the system towards replicating the anatomical structure, composition gradient, and function of intervertebral disc tissue.

  15. Ranges of Cervical Intervertebral Disc Deformation During an In Vivo Dynamic Flexion-Extension of the Neck.

    Science.gov (United States)

    Yu, Yan; Mao, Haiqing; Li, Jing-Sheng; Tsai, Tsung-Yuan; Cheng, Liming; Wood, Kirkham B; Li, Guoan; Cha, Thomas D

    2017-06-01

    While abnormal loading is widely believed to cause cervical spine disc diseases, in vivo cervical disc deformation during dynamic neck motion has not been well delineated. This study investigated the range of cervical disc deformation during an in vivo functional flexion-extension of the neck. Ten asymptomatic human subjects were tested using a combined dual fluoroscopic imaging system (DFIS) and magnetic resonance imaging (MRI)-based three-dimensional (3D) modeling technique. Overall disc deformation was determined using the changes of the space geometry between upper and lower endplates of each intervertebral segment (C3/4, C4/5, C5/6, and C6/7). Five points (anterior, center, posterior, left, and right) of each disc were analyzed to examine the disc deformation distributions. The data indicated that between the functional maximum flexion and extension of the neck, the anterior points of the discs experienced large changes of distraction/compression deformation and shear deformation. The higher level discs experienced higher ranges of disc deformation. No significant difference was found in deformation ranges at posterior points of all the discs. The data indicated that the range of disc deformation is disc level dependent and the anterior region experienced larger changes of deformation than the center and posterior regions, except for the C6/7 disc. The data obtained from this study could serve as baseline knowledge for the understanding of the cervical spine disc biomechanics and for investigation of the biomechanical etiology of disc diseases. These data could also provide insights for development of motion preservation surgeries for cervical spine.

  16. TGFβ regulates Galectin-3 expression through canonical Smad3 signaling pathway in nucleus pulposus cells: implications in intervertebral disc degeneration.

    Science.gov (United States)

    Tian, Ye; Yuan, Wen; Li, Jun; Wang, Hua; Hunt, Maxwell G; Liu, Chao; Shapiro, Irving M; Risbud, Makarand V

    2016-03-01

    Galectin-3 is highly expressed in notochordal nucleus pulposus (NP) and thought to play important physiological roles; however, regulation of its expression remains largely unexplored. The aim of the study was to investigate if TGFβ regulates Galectin-3 expression in NP cells. TGFβ treatment resulted in decreased Galectin-3 expression. Bioinformatic analysis using JASPAR and MatInspector databases cross-referenced with published ChIP-Seq data showed nine locations of highly probable Smad3 binding in the LGALS3 proximal promoter. In NP cells, TGFβ treatment resulted in decreased activity of reporters harboring several 5' deletions of the proximal Galectin-3 promoter. While transfection of NP cells with constitutively active (CA)-ALK5 resulted in decreased promoter activity, DN-ALK5 blocked the suppressive effect of TGFβ on the promoter. The suppressive effect of Smad3 on the Galectin-3 promoter was confirmed using gain- and loss-of-function studies. Transfection with DN-Smad3 or Smad7 blocked TGFβ mediated suppression of promoter activity. We also measured Galectin-3 promoter activity in Smad3 null and wild type cells. Noteworthy, promoter activity was suppressed by TGFβ only in wild type cells. Likewise, stable silencing of Smad3 in NP cells using sh-Smad3 significantly blocked TGFβ-dependent decrease in Galectin-3 expression. Treatment of human NP cells isolated from tissues with different grades of degeneration showed that Galectin-3 expression was responsive to TGF-β-mediated suppression. Importantly, Galectin-3 synergized effects of TNF-α on inflammatory gene expression by NP cells. Together these studies suggest that TGFβ, through Smad3 controls Galectin-3 expression in NP cells and may have implications in the intervertebral disc degeneration. Copyright © 2015 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

  17. Thermal Test on Target with Pressed Disks

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dalmas, Dale Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chemerisov, Sergey [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gromov, Roman [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lowden, Rick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-27

    A thorough test of the thermal performance of a target for Mo99 production using solid Mo100 target to produce the Mo99 via a gamma-n reaction has previously been conducted at Argonne National Laboratory (ANL). The results are reported in “Zero Degree Line Mo Target Thermal Test Results and Analysis,” LANL report Number LA-UR-15-23134 dated 3/27/15. This target was comprised of 25 disks 1 mm thick and 12 mm in diameter, separated by helium coolant gaps 0.5 mm wide. The test reported in the above referenced report was conducted with natural Mo disks all cut from commercial rod. The production plant will have Mo100 disks pressed and sintered using a process being developed at Oak Ridge National Laboratory (ORNL). The structural integrity of press-and-sinter disks is of some concern. The test reported herein included 4 disks made by the ORNL process and placed in the high heat, and therefore high thermal stress, region of the target. The electron beam energy was 23 MeV for these tests. Beam spot size was 3.5 mm horizontal and 3 mm vertical, FWHM. The thermal stress test of pressed-and-sintered disks resulted in no mechanical failures. The induced thermal stresses were below yield stress for natural Mo, indicating that up to that stress state no inherent deficiencies in the mechanical properties of the fabricated disks were evident.

  18. Ultraviolet Echoes of Quasar Accretion Disks

    Science.gov (United States)

    Trump, Jonathan

    2017-08-01

    We propose a novel ultraviolet monitoring campaign with WFC3/UVIS to measure quasar accretion disk structure. The bulk of supermassive black hole growth occurs in luminous quasar phases of rapid accretion, yet the governing physics remains poorly understood. Continuum reverberation mapping (RM) measures the accretion disk size via the time lag between short- and long-wavelength emission: the proposed UV monitoring forms the foundation for simultaneous optical observations (expected to continue for our quasars through 2019). Currently only 4 Seyfert AGNs have UV/optical RM accretion-disk sizes, all low-luminosity and at z<0.02. We propose to monitor 5 new quasars, spanning an order of magnitude higher accretion rate and out to z 1. The 5 quasar targets are drawn from SDSS-RM, a pioneering multi-object spectroscopic RM campaign, and have been monitored with optical photometry and spectroscopy since 2014. The higher luminosity and accurate RM masses of our sample enable the first measurements of accretion-rate effects on accretion-disk size, with UV monitoring directly probing changes in the inner disk suggested by theory and previous indirect observations. Our proposed HST monitoring campaign is unusually efficient, targeting 5 quasars per orbit using the DASH method with UVIS subarray readouts. We use simulations to demonstrate that our 2-day cadence over 32 epochs will accurately measure continuum lags and accretion-disk structure. Ultraviolet monitoring of these 5 quasars will enable critical new measurements of accretion-disk structure during the rapid accretion mode that dominates black hole growth.

  19. Characterization of the age-dependent intervertebral disc changes in rabbit by correlation between MRI, histology and gene expression

    Directory of Open Access Journals (Sweden)

    Gauthier Olivier

    2011-07-01

    Full Text Available Abstract Background The present study was conducted to address whether the intervertebral disc of rabbit could be considered (i as a valuable model to provide new insights into the tissue and cellular changes of Nucleus pulposus aging and (ii as an appropriate tool to investigate the efficacy of Nucleus pulposus cell-based biotherapies. Methods Lumbar intervertebral disc from rabbits with increasing ages (1, 6 and 30 month-old were compared by MRI and histological observation using Pfirrmann's grading and Boos' scoring respectively. The expression of transcripts (COL2A1, AGC1, COL1A1, MMP13, BMP2, MGP and p21 in Nucleus pulposus cells were analysed by quantitative real-time PCR. Results MRI analysis indicated an early age-dependent increase in the Pfirrmann's grading. Histological Boos' scoring was also increased. The analysis of transcript expression levels showed that COL2A1 and AGC1 were down-regulated as a function of age. Conversely, COL1A1, MMP-13, BMP-2, MGP and p21 were significantly up-regulated in the Nucleus pulposus cells of aged rabbit intervertebral disc. Conclusions Our study describes the consistency of the rabbit as a model of intervertebral disc changes as a function of age by correlating tissue alteration with cellular modification measured.

  20. The formation of rings and gaps in protoplanetary disks by magnetic disk winds

    Science.gov (United States)

    Suriano, Scott; Li, Zhi-Yun; Krasnopolsky, Ruben; Shang, Hsien

    2018-01-01

    ALMA observations of protoplanetary disks have revealed previously unresolved radial substructure. These observations, along with the need to fully understand the effects of magnetic fields on the angular momentum transport and global evolution of disks, motivate the study of radial substructure formation in protoplanetary disks. Through 2D-axisymmetric, resistive MHD simulations, we show that rings and gaps can be formed in disks purely through MHD processes in one of two ways: (1) from the removal of angular momentum via a disk wind if the wind torque (and, therefore, the wind-driven mass accretion rate) varies as a function of disk radius, and (2) via the transport of mass through so-called “avalanche accretion streams,” which are a manifestation of the magnetorotational instability (MRI) channel flows in two dimensions. When including ambipolar diffusion (AD), we find that the bulk of the accretion in AD-dominated regions of the disk is concentrated in a thin current sheet near the midplane. Accretion through this current sheet drags magnetic field lines inward with the flow, resulting in a pronounced radial pinch of the magnetic field. Eventually, this radial pinch becomes elongated enough for the magnetic field to reconnect, forming a poloidal magnetic field loop where mass can be concentrated into a dense ring. These mechanisms provide plausible explanations for the radial substructure observed in protoplanetary disks on the tens of au scale.

  1. Cold disks : Spitzer spectroscopy of disks around young stars with large gaps

    NARCIS (Netherlands)

    Blake, G. A.; Dullemond, C. P.; Merin, B.; Augereau, J. C.; Boogert, A. C. A.; Evans, N. J.; Geers, V. C.; Lahuis, F.; Kessler-Silacci, J. E.; Pontoppidan, K. M.; van Dishoeck, E. F.; Brown, J.M.

    2007-01-01

    We have identified four circumstellar disks with a deficit of dust emission from their inner 15-50 AU. All four stars have F-G spectral type and were uncovered as part of the Spitzer Space Telescope "Cores to Disks" Legacy Program Infrared Spectrograph (IRS) first-look survey of similar to 100 pre -

  2. Equilibrium configuration of a stratus floating above accretion disks: Full-disk calculation

    Science.gov (United States)

    Itanishi, Yusuke; Fukue, Jun

    2017-06-01

    We examine floating strati above a luminous accretion disk, supported by the radiative force from the entire disk, and calculate the equilibrium locus, which depends on the disk luminosity and the optical depth of the stratus. Due to the radiative transfer effect (albedo effect), the floating height of the stratus with a finite optical depth generally becomes high, compared with the particle case. In contrast to the case of the near-disk approximation, moreover, the floating height becomes yet higher in the present full-disk calculation, since the intense radiation from the inner disk is taken into account. As a result, when the disk luminosity normalized by the Eddington luminosity is ˜0.3 and the stratus optical depth is around unity, the stable configuration disappears at around r ˜ 50 rg, rg being the Schwarzschild radius, and the stratus would be blown off as a cloudy wind consisting of many strati with appropriate conditions. This luminosity is sufficiently smaller than the Eddington one, and the present results suggest that the radiation-driven cloudy wind can be easily blown off from the sub-Eddington disk, and this can explain various outflows observed in ultra-fast outflow objects as well as in broad-absorption-line quasars.

  3. The Tilt between Acretion Disk and Stellar Disk Shiyin Shen1,2 ...

    Indian Academy of Sciences (India)

    to a control galaxy sample. Given that the Type 2 AGN fraction is in the range of 70–90 percent for low luminosity AGNs as a priori, we find that the mean tilt between the accretion disk and stellar disk is ∼ 30 degrees. (Shen et al. 2010). Key words. Galaxies: statistics—galaxies: Seyfert—galaxies: nuclei— galaxies: spiral. 1.

  4. Influence of Porcine Intervertebral Disc Matrix on Stem Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Hans-Lothar Fuchsbauer

    2011-08-01

    Full Text Available For back disorders, cell therapy is one approach for a real regeneration of a degenerated nucleus pulposus. Human mesenchymal stem cells (hMSC could be differentiated into nucleus pulposus (NP-like cells and used for cell therapy. Therefore it is necessary to find a suitable biocompatible matrix, which supports differentiation. It could be shown that a differentiation of hMSC in a microbial transglutaminase cross-linked gelatin matrix is possible, but resulted in a more chondrocyte-like cell type. The addition of porcine NP extract to the gelatin matrix caused a differentiation closer to the desired NP cell phenotype. This concludes that a hydrogel containing NP extract without any other supplements could be suitable for differentiation of hMSCs into NP cells. The NP extract itself can be cross-linked by transglutaminase to build a hydrogel free of NP atypical substrates. As shown by side-specific biotinylation, the NP extract contains molecules with free glutamine and lysine residues available for the transglutaminase.

  5. Manipulation of magnetic vortex parameters in disk-on-disk nanostructures with various geometry.

    Science.gov (United States)

    Stebliy, Maxim E; Kolesnikov, Alexander G; Ognev, Alexey V; Samardak, Alexander S; Chebotkevich, Ludmila A

    2015-01-01

    Magnetic nanostructures in the form of a sandwich consisting of two permalloy (Py) disks with diameters of 600 and 200 nm separated by a nonmagnetic interlayer are studied. Magnetization reversal of the disk-on-disk nanostructures depends on the distance between centers of the small and big disks and on orientation of an external magnetic field applied during measurements. It is found that manipulation of the magnetic vortex chirality and the trajectory of the vortex core in the big disk is only possible in asymmetric nanostructures. Experimentally studied peculiarities of a motion path of the vortex core and vortex parameters by the magneto-optical Kerr effect (MOKE) magnetometer are supported by the magnetic force microscopy imaging and micromagnetic simulations.

  6. Manipulation of magnetic vortex parameters in disk-on-disk nanostructures with various geometry

    Directory of Open Access Journals (Sweden)

    Maxim E. Stebliy

    2015-03-01

    Full Text Available Magnetic nanostructures in the form of a sandwich consisting of two permalloy (Py disks with diameters of 600 and 200 nm separated by a nonmagnetic interlayer are studied. Magnetization reversal of the disk-on-disk nanostructures depends on the distance between centers of the small and big disks and on orientation of an external magnetic field applied during measurements. It is found that manipulation of the magnetic vortex chirality and the trajectory of the vortex core in the big disk is only possible in asymmetric nanostructures. Experimentally studied peculiarities of a motion path of the vortex core and vortex parameters by the magneto-optical Kerr effect (MOKE magnetometer are supported by the magnetic force microscopy imaging and micromagnetic simulations.

  7. Probing Protoplanetary Disks: From Birth to Planets

    Science.gov (United States)

    Guilfoil Cox, Erin

    2018-01-01

    Disks are very important in the evolution of protostars and their subsequent planets. How early disks can form has implications for early planet formation. In the youngest protostars (i.e., Class 0 sources) magnetic fields can control disk growth. When the field is parallel to the collapsing core’s rotation axis, infalling material loses angular momentum and disks form in later stages. Sub-/millimeter polarization continuum observations of Class 0 sources at ~1000 au resolution support this idea. However, in the inner (~100 au), denser regions, it is unknown if the polarization only traces aligned dust grains. Recent theoretical studies have shown that self-scattering of thermal emission in the disk may contribute significantly to the polarization. Determining the scattering contribution in these sources is important to disentangle the magnetic field. At older times (the Class II phase), the disk structure can both act as a modulator and signpost of planet formation, if there is enough of a mass reservoir. In my dissertation talk, I will present results that bear on disk evolution at both young and late ages. I will present 8 mm polarization results of two Class 0 protostars (IRAS 4A and IC348 MMS) from the VLA at ~50 au resolution. The inferred magnetic field of IRAS 4A has a circular morphology, reminiscent of material being dragged into a rotating structure. I will show results from SOFIA polarization data of the area surrounding IRAS 4A at ~4000 au. I will also present ALMA 850 micron polarization data of ten protostars in the Perseus Molecular Cloud. Most of these sources show very ordered patterns and low (~0.5%) polarization in their inner regions, while having very disordered patterns and high polarization patterns in their extended emission that may suggest different mechanisms in the inner/outer regions. Finally, I will present results from our ALMA dust continuum survey of protoplanetary disks in Rho Ophiuchus; we measured both the sizes and fluxes of

  8. Theory of Disk-to-Vesicle Transformation

    Science.gov (United States)

    Li, Jianfeng; Shi, An-Chang

    2009-03-01

    Self-assembled membranes from amphiphilic molecules, such as lipids and block copolymers, can assume a variety of morphologies dictated by energy minimization of system. The membrane energy is characterized by a bending modulus (κ), a Gaussian modulus (κG), and the line tension (γ) of the edge. Two basic morphologies of membranes are flat disks that minimize the bending energy at the cost of the edge energy, and enclosed vesicles that minimize the edge energy at the cost of bending energy. In our work, the transition from disk to vesicle is studied theoretically using the string method, which is designed to find the minimum energy path (MEP) or the most probable transition path between two local minima of an energy landscape. Previous studies of disk-to-vesicle transition usually approximate the transitional states by a series of spherical cups, and found that the spherical cups do not correspond to stable or meta-stable states of the system. Our calculation demonstrates that the intermediate shapes along the MEP are very different from spherical cups. Furthermore, some of these transitional states can be meta-stable. The disk-to-vesicle transition pathways are governed by two scaled parameters, κG/κ and γR0/4κ, where R0 is the radius of the disk. In particular, a meta-stable intermediate state is predicted, which may correspond to the open morphologies observed in experiments and simulations.

  9. Disk-Jet Connection in Active Supermassive Black Holes in the Standard Accretion Disk Regime

    Science.gov (United States)

    Inoue, Yoshiyuki; Doi, Akihiro; Tanaka, Yasuyuki T.; Sikora, Marek; Madejski, Grzegorz M.

    2017-05-01

    We study the disk-jet connection in supermassive black holes by investigating the properties of their optical and radio emissions utilizing the SDSS DR7 and the NVSS catalogs. Our sample contains 7017 radio-loud quasars with detection both at 1.4 GHz and SDSS optical spectra. Using this radio-loud quasar sample, we investigate the correlation among the jet power ({P}{jet}), the bolometric disk luminosity ({L}{disk}), and the black hole mass ({M}{BH}) in the standard accretion disk regime. We find that the jet powers correlate with the bolometric disk luminosities as {log}{P}{jet}=(0.96+/- 0.012){log}{L}{disk}+(0.79+/- 0.55). This suggests the jet production efficiency of {η }{jet}≃ {1.1}-0.76+2.6 × {10}-2 assuming the disk radiative efficiency of 0.1, implying low black hole spin parameters and/or low magnetic flux for radio-loud quasars. But it can be also due to the dependence of this efficiency on the geometrical thickness of the accretion flow, which is expected to be small for quasars accreting at the disk Eddington ratios 0.01≲ λ ≲ 0.3. This low jet production efficiency does not significantly increase even if we set the disk radiative efficiency to be 0.3. We also investigate the fundamental plane in our samples among {P}{jet}, {L}{disk}, and {M}{BH}. We could not find a statistically significant fundamental plane for radio-loud quasars in the standard accretion regime.

  10. Formulas for Radial Transport in Protoplanetary Disks

    Science.gov (United States)

    Desch, Steven J.; Estrada, Paul R.; Kalyaan, Anusha; Cuzzi, Jeffrey N.

    2017-05-01

    The quantification of the radial transport of gaseous species and solid particles is important to many applications in protoplanetary disk evolution. An especially important example is determining the location of the water snow lines in a disk, which requires computing the rates of outward radial diffusion of water vapor and the inward radial drift of icy particles; however, the application is generalized to evaporation fronts of all volatiles. We review the relevant formulas using a uniform formalism. This uniform treatment is necessary because the literature currently contains at least six mutually exclusive treatments of radial diffusion of gas, only one of which is correct. We derive the radial diffusion equations from first principles using Fick's law. For completeness, we also present the equations for radial transport of particles. These equations may be applied to studies of diffusion of gases and particles in protoplanetary and other accretion disks.

  11. Random Number Generators in Secure Disk Drives

    Directory of Open Access Journals (Sweden)

    Hars Laszlo

    2009-01-01

    Full Text Available Abstract Cryptographic random number generators seeded by physical entropy sources are employed in many embedded security systems, including self-encrypting disk drives, being manufactured by the millions every year. Random numbers are used for generating encryption keys and for facilitating secure communication, and they are also provided to users for their applications. We discuss common randomness requirements, techniques for estimating the entropy of physical sources, investigate specific nonrandom physical properties, estimate the autocorrelation, then mix reduce the data until all common randomness tests pass. This method is applied to a randomness source in disk drives: the always changing coefficients of an adaptive filter for the read channel equalization. These coefficients, affected by many kinds of physical noise, are used in the reseeding process of a cryptographic pseudorandom number generator in a family of self encrypting disk drives currently in the market.

  12. Subaru SEEDS Survey of Exoplanets and Disks

    Science.gov (United States)

    McElwain, Michael W.

    2012-01-01

    The Strategic Exploration of Exoplanets and Disks at Subaru (SEEDS) is the first strategic observing program (SSOPs) awarded by the National Astronomical Observatory of Japan (NAOJ). SEEDS targets a broad sample of stars that span a wide range of masses and ages to explore the formation and evolution of planetary systems. This survey has been awarded 120 nights over five years time to observe nearly 500 stars. Currently in the second year, SEEDS has already produced exciting new results for the protoplanetary disk AB Aur, transitional disk LkCa15, and nearby companion to GJ 758. We present the survey architecture, performance, recent results, and the projected sample. Finally, we will discuss planned upgrades to the high contrast instrumentation at the Subaru Telescope

  13. Heating and cooling processes in disks

    Science.gov (United States)

    Woitke, Peter

    2015-09-01

    This chapter summarises current theoretical concepts and methods to determine the gas temperature structure in protoplanetary disks by balancing all relevant heating and cooling rates. The processes considered are non-LTE line heating/cooling based on the escape probability method, photo-ionisation heating and recombination cooling, free-free heating/cooling, dust thermal accommodation and high-energy heating processes such as X-ray and cosmic ray heating, dust photoelectric and PAH heating, a number of particular follow-up heating processes starting with the UV excitation of H2, and the release of binding energy in exothermal reactions. The resulting thermal structure of protoplanetary disks is described and discussed. 10th Lecture from Summer School "Protoplanetary Disks: Theory and Modelling Meet Observations"

  14. Toshiba Optical Disk Stores 15000 CT Images

    Science.gov (United States)

    Kato, Haruo; Kita, Kouichi

    1984-08-01

    The Toshiba computed tomography scanner system TCT60A/500X is equipped with an optical disk data storage device for image data archiving. One optical disk stores 3.6 gigabytes of data, or 15000 CT images on both sides. When writing on an optical disk, one spiral of data pits is produced with a semiconductor laser by evaporating the Te-C film coated on the PMMA (poly(methyl methacrylate)) substrate. The pits are read by the same laser at a lower power along with CRC (cyclic redundancy code) error correction. A bit error rate of 1.0E-12 was attained. The IEEE488 interface bus (GPIB) is used to communicate with a host computer. The mean data transfer rate through the bus is 100 kilobytes per second.

  15. Simulating a Thin Accretion Disk Using PLUTO

    Science.gov (United States)

    Phillipson, Rebecca; Vogeley, Michael S.; Boyd, Patricia T.

    2017-08-01

    Accreting black hole systems such as X-ray binaries and active galactic nuclei exhibit variability in their luminosity on many timescales ranging from milliseconds to tens of days, and even hundreds of days. The mechanism(s) driving this variability and the relationship between short- and long-term variability is poorly understood. Current studies on accretion disks seek to determine how the changes in black hole mass, the rate at which mass accretes onto the central black hole, and the external environment affect the variability on scales ranging from stellar-mass black holes to supermassive black holes. Traditionally, the fluid mechanics equations governing accretion disks have been simplified by considering only the kinematics of the disk, and perhaps magnetic fields, in order for their phenomenological behavior to be predicted analytically. We seek to employ numerical techniques to study accretion disks including more complicated physics traditionally ignored in order to more accurately understand their behavior over time. We present a proof-of-concept three dimensional, global simulation using the astrophysical hydrodynamic code PLUTO of a simplified thin disk model about a central black hole which will serve as the basis for development of more complicated models including external effects such as radiation and magnetic fields. We also develop a tool to generate a synthetic light curve that displays the variability in luminosity of the simulation over time. The preliminary simulation and accompanying synthetic light curve demonstrate that PLUTO is a reliable code to perform sophisticated simulations of accretion disk systems which can then be compared to observational results.

  16. Moving groups in the Galactic thin disk

    Science.gov (United States)

    Ramya, P.; Reddy, Bacham Eswar

    Apart from the large scale structures named as thick disk and thin disk, many small scale structures or overdensities are observed in the velocity fields of disk stars in the solar neighborhood. Such structures include open clusters, OB associations, stellar streams etc. Stellar streams or moving groups are kinematically coherent groups of stars which are gravitationally unbound and are seen scattered all over the sky. Although they have been known and studied for long, their origin is not well understood. The most popular scenarios explaining the origin of moving groups are cluster disruption, dynamical perturbations within the Galaxy and the tidal disruption of satellite galaxies by the Galaxy. Arcturus stream is a well known example of streams in the thick disk, while Hercules stream, Sirius stream, Hyades stream etc, are the popular ones in the thin disk of the Galaxy. Here, we present the results of our analysis of three streams -Sirius, Hercules and Hyades. Candidate members for each of the streams were chosen based on the kinematic classification provided in the literature. The kinematic motion (U, V, W) of the sample stars, and the probability with which stars belong to the Galactic thin disk are calculated. Main focus of our study is to understand the chemistry of the stream members. The detailed chemical composition is obtained through high resolution spectroscopy and the results are compared with the abundance patterns of different Galactic components. We do not find chemical homogeneity among the stream members. It appears that the member stars are of different origin. Although, the abundance patterns in these streams favour dynamical perturbations within the Galaxy, the association of Hyades stream with Hyades cluster has been discussed.

  17. Reoperation rate after surgery for lumbar herniated intervertebral disc disease: nationwide cohort study.

    Science.gov (United States)

    Kim, Chi Heon; Chung, Chun Kee; Park, Choon Seon; Choi, Boram; Kim, Min Jung; Park, Byung Joo

    2013-04-01

    Retrospective cohort study using national health insurance data. To provide a longitudinal reoperation rate after surgery for lumbar herniated intervertebral disc (HIVD) disease, and to compare the reoperation rates of surgical methods. Herniated intervertebral disc disease is the most common cause of lumbar spinal surgery. Despite improved surgical techniques and instrumentation, reoperation cannot be avoided. The reoperation rates were in the range of 6% to 24% in previous studies. A population-based study is less subject to bias; hence, a nationwide longitudinal analysis was warranted. A national health insurance database was used to identify a cohort of patients who underwent first surgery for herniated intervertebral disc disease in 2003 and 18,590 patients were selected. Individual patients were followed for at least 5 years through their encrypted unique resident registration number. The primary endpoint was any type of second lumbar surgery. After adjusting for confounding factors, 5 surgical methods (fusion, laminectomy, open discectomy, endoscopic discectomy, and nucleolysis [including mechanical nucleus decompression]) were compared. Open discectomy was used as the reference method. Open discectomy was the most common procedure (68.9%) followed by endoscopic discectomy (16.1%), laminectomy (7.9%), fusion (3.9%), and nucleolysis (3.2%). The cumulative reoperation rate was 5.4% at 3 months, 7.4% at 1 year, 9% at 2 years, 10.5% at 3 years, 12.1% at 4 years, and 13.4% at 5 years. The reoperation rates were 18.6%, 14.7%, 13.8%, 12.4%, and 11.8% after laminectomy, nucleolysis, open discectomy, endoscopic discectomy, and fusion, respectively. Compared with open discectomy, the reoperation rate was higher after laminectomy at 3 months, whereas the other surgical methods had similar rates. The cumulative reoperation rate after 5 years was 13.4% and half of the reoperations occurred during the first postoperative year. With the exception of laminectomy, the

  18. Topical vancomycine and bacterial culture from intervertebral herniated disc prevent postoperative osteodiscitis

    Directory of Open Access Journals (Sweden)

    Adam1 Danil

    2014-12-01

    Full Text Available Osteodiscitis represents a serious complication of lumbar disc herniation operations. The treatment of osteodiscitis is controversial and expensive to society. It extends over a period of several months from diagnosis. Reducing postoperative osteodiscitis by using simple measures may limit patient's suffering and reduce costs. The purpose of this study is to evaluate the early diagnosis of bacterial infections of the intervertebral disc by isolating germs located in the herniated disc fragment and topical Vancomycine powder application, along with the conventional anti-infective therapy. Medical files of patients who were operated on for lumbar disc herniations during 01.01.2013 - 30.06.2014 were reviewed. The diagnosis of lumbar disc herniation was established based on the clinical evaluation, confirmed by MRI results. The surgical intervention was performed by mini-open approach: fenestration and foraminotomy completed with removal of the herniated disc fragment and disc remnants from the intervertebral space. A group of 162 patients (group A received conventional therapy for prevention of post-operative infections with 2 doses of cephalosporin. In the second group of 137 patients (group B, after the removal of the herniated disc fragments, 1g of Vancomycine powder was topically applied and the disc fragments were bacteriologically analyzed. They received the conventional treatment of preventing post-operative infections with cephalosprin - 2 doses. The two groups of patients were similar in terms of demographic characteristics: age, sex, operative level. Out of the 162 patients of group A, one patient developed postoperative osteodiscitis and was treated for 3 months with antibiotics. Regarding patients in group B, in four cases Staphylococcus was isolated from the disc fragments. Postoperative treatment for these patients with prolonged antibiotic therapy over the standard period avoided the developement of the clinical picture of

  19. Bupivacaine decreases cell viability and matrix protein synthesis in an intervertebral disc organ model system.

    Science.gov (United States)

    Wang, Dong; Vo, Nam V; Sowa, Gwendolyn A; Hartman, Robert A; Ngo, Kevin; Choe, So Ra; Witt, William T; Dong, Qing; Lee, Joon Y; Niedernhofer, Laura J; Kang, James D

    2011-02-01

    Bupivacaine is a local anesthetic commonly used for back pain management in interventional procedures. Cytotoxic effects of bupivacaine have been reported in articular cartilage and, recently, in intervertebral disc cell culture. However, the relevance of these effects to discs in vivo remains unclear. This study examines the effect of bupivacaine on disc cell metabolism using an organotypic culture model system that mimics the in vivo environment. To assess the effect of bupivacaine on disc cell viability and matrix protein synthesis using an organotypic model system and to determine whether this anesthetic has toxic effects. Mouse intervertebral discs were isolated and maintained ex vivo in an organotypic culture then exposed to clinically relevant concentrations of bupivacaine, and the impact on disc cell viability and matrix proteoglycan (PG) and collagen syntheses were measured in the presence and absence of the drug. Mouse functional spine units (FSUs) were isolated from the lumbar spines of 10-week-old mice. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Total PG and collagen syntheses were determined by measuring the incorporation of radioactive (35)S-sulfate and (3)H-l-proline into PG and collagen, respectively. Organotypic cultures of mouse FSUs were exposed to different concentrations (0%-0.5%) of bupivacaine for variable amounts of time (0-2 hours). Cell viability within disc tissue was quantified by MTT staining and histologic assay. Matrix protein synthesis was measured by incorporation of radioactive (35)S-sulfate (for PG synthesis) and (3)H-l-proline (for collagen synthesis). Untreated mouse disc organs were maintained in culture for up to 1 month with minimal changes in tissue histology, cell viability, and matrix protein synthesis. Exposure to bupivacaine decreased cell viability in a dose- and time-dependent manner. Exposure to bupivacaine at concentrations less than or equal to 0.25% did

  20. Capillary condensation between disks in two dimensions

    DEFF Research Database (Denmark)

    Gil, Tamir; Ipsen, John Hjorth

    1997-01-01

    Capillary condensation between two two-dimensional wetted circular substrates (disks) is studied by an effective free energy description of the wetting interface. The interfacial free-energy potential is developed on the basis of the theory for the wetting of a single disk, where interfacial...... capillary fluctuations play a dominant role. A simple approximative analytical expression of the interfacial free energy is developed and is validated numerically. The capillary condensation is characterized by the analysis of the coverage of the condensed phase, its stability, and asymptotic behaviors...

  1. Protogalaxies. [with early disk and spheroid systems

    Science.gov (United States)

    Cowie, Lennox L.

    1988-01-01

    It is argued that the observed sample of flat-spectrum galaxies seen in recent deep surveys must contain both early disk systems and early spheroid systems in order to match observed number counts if q sub 0 = 0.5. The low average density of neutral hydrogen in damped L-alpha systems at z = 2 - 3 separates the disk formation at z less than about 2 from spheroid formation at z greater than about 3. Based on color arguments, the period of spheroid formation is assigned to z = 4.

  2. Winds from disks in compact binaries

    Energy Technology Data Exchange (ETDEWEB)

    Mauche, C.W.

    1993-10-27

    We herein present an observational and theoretical review of the winds of compact binaries. After a brief consideration of the accretion disk coronae and winds of X-ray binaries, the review concentrates on the winds of cataclysmic variables (CVs). Specifically, we consider the related problems of the geometry and mass-loss rate of the winds of CVs, their ionization state and variability, and the results from studies of eclipsing CVs. Finally, the properties of bona fide accretion disk wind models are reviewed.

  3. The Rossby wave instability in protoplanetary disks

    Directory of Open Access Journals (Sweden)

    Meheut H.

    2013-04-01

    Full Text Available The Rossby wave instability has been proposed as a mechanism to transport angular momentum in the dead zone of protoplanetary disks and to form vortices. These vortices are of particular interest to concentrate solids in their centres and eventually to form planetesimals. Here we summarize some recent results concerning the growth and structure of this instability in radially and vertically stratified disks, its saturation and non-linear evolution. We also discuss the concentration of solids in the Rossby vortices including vertical settling.

  4. Debris Disks in Aggregate: Using Hubble Space Telescope Coronagraphic Imagery to Understand the Scattered-Light Disk Detection Rate

    Science.gov (United States)

    Grady, Carol A.

    2011-01-01

    Despite more than a decade of coronagraphic imaging of debris disk candidate stars, only 16 have been imaged in scattered light. Since imaged disks provide our best insight into processes which sculpt disks, and can provide signposts of the presence of giant planets at distances which would elude radial velocity and transit surveys, we need to understand under what conditions we detect the disks in scattered light, how these disks differ from the majority of debris disks, and how to increase the yield of disks which are imaged with 0.1" angular resolution. In this talk, I will review what we have learned from a shallow HSTINICMOS NIR survey of debris disks, and present first results from our on-going HST /STIS optical imaging of bright scattered-light disks.

  5. Fomalhaut's Debris Disk and Planet: Constraining the Mass of Formalhaut B from Disk Morphology

    Science.gov (United States)

    Chiang, E.; Kite, E.; Kalas, P.; Graham, J. R.; Clampin, M.

    2008-01-01

    Following the optical imaging of exoplanet candidate Fomalhaut b (Fom b), we present a numerical model of how Fomalhaut's debris disk is gravitationally shaped by a single interior planet. The model is simple, adaptable to other debris disks, and can be extended to accommodate multiple planets. If Fom b is the dominant perturber of the belt, then to produce the observed disk morphology it must have a mass M(sub pl) 101.5AU, and an orbital eccentricity e(sub pl) = 0.11 - 0.13. These conclusions are independent of Fom b's photometry. To not disrupt the disk, a greater mass for Fom b demands a smaller orbit farther removed from the disk; thus, future astrometric measurement of Fom b's orbit, combined with our model of planet-disk interaction, can be used to determine the mass more precisely. The inner edge of the debris disk at a approximately equals 133AU lies at the periphery of Fom b's chaotic zone, and the mean disk eccentricity of e approximately equals 0.11 is secularly forced by the planet, supporting predictions made prior to the discovery of Fom b. However, previous mass constraints based on disk morphology rely on several oversimplifications. We explain why our constraint is more reliable. It is based on a global model of the disk that is not restricted to the planet's chaotic zone boundary. Moreover, we screen disk parent bodies for dynamical stability over the system age of approximately 100 Myr, and model them separately from their dust grain progeny; the latter's orbits are strongly affected by radiation pressure and their lifetimes are limited to approximately 0.1 Myr by destructive grain-grain collisions. The single planet model predicts that planet and disk orbits be apsidally aligned. Fomalhaut b's nominal space velocity does not bear this out, but the astrometric uncertainties are difficult to quantify. Even if the apsidal misalignment proves real, our calculated upper mass limit of 3 M(sub J) still holds. Parent bodies are evacuated from mean

  6. Development of a method for quantitative measures of lumbar intervertebral disc structures

    DEFF Research Database (Denmark)

    Tunset, Andreas; Kjær, Per; Chreiteh, Shadi Samir

    2013-01-01

    applicable description of quantitative methods for measuring lumbar disc herniations and related structures on sagittal MRIs. The objectives of this study were: 1) to develop methods for quantitative measures of intervertebral discs, lumbar disc herniations and dural sac/spinal canal using MRIs, 2......Background: Detailed information about the development of disc morphology over time could provide valuable knowledge about disc health when compared with clinical measures such as pain and activity limitation. However, a review of the available literature did not reveal any detailed and directly......) to evaluate the agreement of these methods, and 3) to identify factors in the measurement procedures that may compromise agreement. Methods: In this intra- and inter-rater agreement study, lumbar quantitative measurements were performed on magnetic resonance images from 32 participants from a study cohort...

  7. Conservative therapy for lumbar intervertebral disc hernia. Intradiscal compressive injection and MRI findings

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Tohru; Nanba, Hiromichi; Kasai, Tsutomu; Ohta, Susumu [Yoshida Orthopaedic Hospital, Toyota, Aichi (Japan)

    1996-01-01

    To herniating intervertebral discs, 3-20 ml physiological saline was pressurized and injected. To avoid excessive force, the injection pressure was set at less than 3 kg/cm{sup 2}. Between January 1993 and December 1994, 380 cases were studied (286 men and 94 women with a mean age of 45.5 years). After the compressive injection there were 259 (68.2%) effective cases in which symptoms were relieved and 121 ineffective cases (31.8%). The proportion of effective cases was higher in women than in men and in older than in younger patients. After intradiscal pressurized injection, the effective cases were investigated with MRI and a tendency to relatively early shrinkage of herniated mass was noted. (author).

  8. Hydrogel-Based Platforms for the Regeneration of Osteochondral Tissue and Intervertebral Disc

    Directory of Open Access Journals (Sweden)

    Luigi Ambrosio

    2012-09-01

    Full Text Available Hydrogels currently represent a powerful solution to promote the regeneration of soft and hard tissues. Primarily, they assure efficient bio-molecular interactions with cells, also regulating their basic functions, guiding the spatially and temporally complex multi-cellular processes of tissue formation, and ultimately facilitating the restoration of structure and function of damaged or dysfunctional tissues. In order to overcome basic drawbacks of traditional synthesized hydrogels, many recent strategies have been implemented to realize multi-component hydrogels based on natural and/or synthetic materials with tailored chemistries and different degradation kinetics. Here, a critical review of main strategies has been proposed based on the use of hydrogels-based devices for the regeneration of complex tissues, i.e., osteo-chondral tissues and intervertebral disc.

  9. Discoscopic Findings of High Signal Intensity Zones on Magnetic Resonance Imaging of Lumbar Intervertebral Discs

    Directory of Open Access Journals (Sweden)

    Kosuke Sugiura

    2014-01-01

    Full Text Available A 32-year-old man underwent radiofrequency thermal annuloplasty (TA with percutaneous endoscopic discectomy (PED under local anesthesia for chronic low back pain. His diagnosis was discogenic pain with a high signal intensity zone (HIZ in the posterior corner of the L4-5 disc. Flexion pain was sporadic, and steroid injection was given twice for severe pain. After the third episode of strong pain, PED and TA were conducted. The discoscope was inserted into the posterior annulus and revealed a migrated white nucleus pulposus which was stained blue. Then, after moving the discoscope to the site of the HIZ, a migrated slightly red nucleus pulposus was found, suggesting inflammation and/or new vessels penetrating the mass. After removing the fragment, the HIZ site was ablated by TA. To our knowledge, this is the first report of the discoscopic findings of HIZ of the lumbar intervertebral disc.

  10. Cell and molecular biology of intervertebral disc degeneration: current understanding and implications for potential therapeutic strategies.

    Science.gov (United States)

    Wang, S Z; Rui, Y F; Lu, J; Wang, C

    2014-10-01

    Intervertebral disc degeneration (IDD) is a chronic, complex process associated with low back pain; mechanisms of its occurrence have not yet been fully elucidated. Its process is not only accompanied by morphological changes, but also by systematic changes in its histological and biochemical properties. Many cellular and molecular mechanisms have been reported to be related with IDD and to reverse degenerative trends, abnormal conditions of the living cells and altered cell phenotypes would need to be restored. Promising biological therapeutic strategies still rely on injection of active substances, gene therapy and cell transplantation. With advanced study of tissue engineering protocols based on cell therapy, combined use of seeding cells, bio-active substances and bio-compatible materials, are promising for IDD regeneration. Recently reported progenitor cells within discs themselves also hold prospects for future IDD studies. This article describes the background of IDD, current understanding and implications of potential therapeutic strategies. © 2014 John Wiley & Sons Ltd.

  11. Experiences of intervertebral motion palpation in osteopathic practice - A qualitative interview study among Swedish osteopaths.

    Science.gov (United States)

    Sposato, Niklas S; Bjerså, Kristofer

    2017-01-01

    Assessment in manual therapy includes quantitative and qualitative procedures, and intervertebral motion palpation (IMP) is one of the core assessment methods in osteopathic practice. The aim of this study was to explore osteopathic practitioners' experiences of clinical decision-making and IMP as a diagnostic tool for planning and evaluation of osteopathic interventions. The study was conducted with semi-structured interviews that included eight informants. Content analysis was used as the analytical procedure. In total, three categories emerged from the analysis: strategic decision-making, diagnostic usability of IMP, and treatment applicability of IMP. The study indicated that IMP was considered relevant and was given particular importance in cases where IMP findings confirmed clinical information attained from other stages in the diagnostic process as a whole. However, IMP findings were experienced as less important if they were not correlated to other findings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Characterisation of cytoplasm-filled processes in cells of the intervertebral disc.

    Science.gov (United States)

    Errington, R J; Puustjarvi, K; White, I R; Roberts, S; Urban, J P

    1998-04-01

    We examined cells from the nucleus pulposus and annulus fibrosus of adult bovine intervertebral discs, using confocal laser scanning microscopy on living unfixed tissue. These cells were visualised using chloromethyl fluorescein diacetate, a membrane-impermeant fluorescent dye. The organisation of cells from the outer annulus was also determined using confocal microscopy after fixation and staining the actin-filaments with FITC-phalloidin. We found that cellular processes were a dominant feature of cells from all regions of the disc including the cells of the nucleus pulposus and inner annulus. These processes were also visible in histological sections of disc examined both at the light and electron microscope level, even though cells from the nucleus and inner annulus appeared chondrocyte-like, being rounded and enclosed in a capsule. The function of these processes is at present unknown. We suggest that they may serve to sense mechanical strain.

  13. In-vivo T2-relaxation times of asymptomatic cervical intervertebral discs

    Energy Technology Data Exchange (ETDEWEB)

    Driscoll, Sean J.; Mao, Haiqing; Li, Guoan [Massachusetts General Hospital/Harvard Medical School, Bioengineering Laboratory, Department of Orthopaedic Surgery, Boston, MA (United States); Zhong, Weiye [Massachusetts General Hospital/Harvard Medical School, Bioengineering Laboratory, Department of Orthopaedic Surgery, Boston, MA (United States); Second Xiangya Hospital and Central South University, Department of Spinal Surgery, Changsha, Hunan (China); Torriani, Martin [Massachusetts General Hospital/Harvard Medical School, Musculoskeletal Imaging and Intervention, Department of Radiology, Boston, MA (United States); Wood, Kirkham B.; Cha, Thomas D. [Massachusetts General Hospital/Harvard Medical School, Spine Service, Department of Orthopaedic Surgery, Boston, MA (United States)

    2016-03-15

    Limited research exists on T2-mapping techniques for cervical intervertebral discs and its potential clinical utility. The objective of this research was to investigate the in-vivo T2-relaxation times of cervical discs, including C2-C3 through C7-T1. Ten asymptomatic subjects were imaged using a 3.0 T MR scanner and a sagittal multi-slice multi-echo sequence. Using the mid-sagittal image, intervertebral discs were divided into five regions-of-interest (ROIs), centered along the mid-line of the disc. Average T2 relaxation time values were calculated for each ROI using a mono-exponential fit. Differences in T2 values between disc levels and across ROIs of the same disc were examined. For a given ROI, the results showed a trend of increasing relaxation times moving down the spinal column, particularly in the middle regions (ROIs 2, 3 and 4). The C6-C7 and C7-T1 discs had significantly greater T2 values compared to superior discs (discs between C2 and C6). The results also showed spatial homogeneity of T2 values in the C3-C4, C4-C5, and C5-C6 discs, while C2-C3, C6-C7, and C7-T1 showed significant differences between ROIs. The findings indicate there may be inherent differences in T2-relaxation time properties between different cervical discs. Clinical evaluations utilizing T2-mapping techniques in the cervical spine may need to be level-dependent. (orig.)

  14. Propionibacterium acnes biofilm is present in intervertebral discs of patients undergoing microdiscectomy.

    Directory of Open Access Journals (Sweden)

    Manu N Capoor

    Full Text Available In previous studies, Propionibacterium acnes was cultured from intervertebral disc tissue of ~25% of patients undergoing microdiscectomy, suggesting a possible link between chronic bacterial infection and disc degeneration. However, given the prominence of P. acnes as a skin commensal, such analyses often struggled to exclude the alternate possibility that these organisms represent perioperative microbiologic contamination. This investigation seeks to validate P. acnes prevalence in resected disc cultures, while providing microscopic evidence of P. acnes biofilm in the intervertebral discs.Specimens from 368 patients undergoing microdiscectomy for disc herniation were divided into several fragments, one being homogenized, subjected to quantitative anaerobic culture, and assessed for bacterial growth, and a second fragment frozen for additional analyses. Colonies were identified by MALDI-TOF mass spectrometry and P. acnes phylotyping was conducted by multiplex PCR. For a sub-set of specimens, bacteria localization within the disc was assessed by microscopy using confocal laser scanning and FISH.Bacteria were cultured from 162 discs (44%, including 119 cases (32.3% with P. acnes. In 89 cases, P. acnes was cultured exclusively; in 30 cases, it was isolated in combination with other bacteria (primarily coagulase-negative Staphylococcus spp. Among positive specimens, the median P. acnes bacterial burden was 350 CFU/g (12 - ~20,000 CFU/g. Thirty-eight P. acnes isolates were subjected to molecular sub-typing, identifying 4 of 6 defined phylogroups: IA1, IB, IC, and II. Eight culture-positive specimens were evaluated by fluorescence microscopy and revealed P. acnes in situ. Notably, these bacteria demonstrated a biofilm distribution within the disc matrix. P. acnes bacteria were more prevalent in males than females (39% vs. 23%, p = 0.0013.This study confirms that P. acnes is prevalent in herniated disc tissue. Moreover, it provides the first visual

  15. Laser-treated Nucleus pulposus as an innovative model of intervertebral disc degeneration.

    Science.gov (United States)

    Lucas, Olivier; Hamel, Olivier; Blanchais, Anne; Lesoeur, Julie; Abadie, Jérôme; Fellah, Borhane Hakim; Fusellier, Marion; Gauthier, Olivier; Bord, Eric; Grimandi, Gaël; Vinatier, Claire; Guicheux, Jérôme; Clouet, Johann

    2012-11-01

    This study describes an innovative experimentally induced model of intervertebral disc degeneration. This innovative approach is based on the induction of extracellular matrix disorders in the intervertebral disc (IVD) using a diode laser. For this study, 15 one-year-old and five 30-month-old New Zealand White rabbits were used. Two procedures were tested to trigger IVD degeneration: needle aspiration (reference technique) and a laser approach. The IVD degeneration process was assessed 20, 40, 60, 90 and 120 days after surgery by X-ray radiography (IVD height), magnetic resonance imaging (MRI) (T2 intensity of IVD signal) and histological analysis using modified Boos' scoring. Our data indicate that a marked IVD degeneration was found compared with sham-operated animals regardless of the procedure tested. A significant decrease in disc height on X-ray radiographs was first demonstrated. In addition, MRI disc signals were significantly reduced in both groups. Finally, a statistically significant increase in Boos' scoring was found in both laser and aspiration-induced IVD degeneration. Interestingly, IVD degeneration induced by laser treatment was more progressive compared with aspiration. Moreover, the histological results indicated that laser-induced disc degeneration was quite similar to that obtained during the natural aging process as observed in 30-month-old rabbits. Our study describes the consistency of this innovative experimentally-induced animal model of IVD degeneration. The radiological, MRI and histological data confirm its relevance. The histological examination indicates that IVD degeneration induced by laser treatment is comparable to the degenerative process observed during the onset of spontaneous IVD degeneration. This model could be a useful tool to help us validate biomaterial-assisted, cell-based, regenerative medicine strategies for the prevention and treatment of IVD degeneration.

  16. Spinal Epidural Varices, a great Mimic of Intervertebral Disc Prolapse - A Case Series.

    Science.gov (United States)

    V, Raghavendra; Haridas, Papanaik; Kumar, Anand; K, Ajith

    2014-01-01

    Epidural venous plexus enlargement, presenting with low back pain and radiculopathy, is an uncommon cause of nerve roots impingement. This condition commonly mimics a herniated nucleus pulposus radiologically. The radiological diagnosis is often missed and the diagnosis is made during the surgery. We are hereby presenting 2 such cases of epidural varices mimicking intervertebral disc prolapse with lumbar radiculopathy. Case 1: 43 yr old female presented with acute exacerbation of low back ache and significant right L5-S1 radiculopathy without neurological deficit. MRI reported as L5-S1 disc prolapse. Intra-operatively engorged dilated epidural vein seen compressing S1 nerve root. Associated Disc bulge removed and Coagulative ablation of the dilated epidural vein was performed Case 2: 45 year old male manual labourer presented with backache with left sided sciatica since 8 months, increased in severity since past 1month associated with sensory blunting in L5 and S1 dermatomes. Neurologic examination revealed normal muscle power in his lower extremities. Sensations was blunted in L5 and S1 dermatomes. MRI was reported as L5-S1 disc prolapsed compressing left S1 nerve root. Decompression of the L5-S1 intervertebral space was performed through a left -sidelaminotomy. Large, engorged serpentine epidural veins was found in the axilla of S1 nerve root, compressing it. Coagulative ablation of the dilated epidural vein was performed. Retrospectively, features of epidural varices were noted in the preoperative magnetic resonance imaging scans. Both patients had significant improvement in radiculopathy immediate postoperatively, and sensory symptoms resolved over the next 6 weeks in second case. At recent follow up, both patients had significant relief of symptoms and no recurrent radicular symptoms. An abnormal dilated epidural venous plexus that mimics a herniated lumbar disc is a rare entity. This pathology should be always kept in mind during lumbar disc surgery

  17. Planetary Torque in 3D Isentropic Disks

    Energy Technology Data Exchange (ETDEWEB)

    Fung, Jeffrey [Department of Astronomy, University of California at Berkeley, Campbell Hall, Berkeley, CA 94720-3411 (United States); Masset, Frédéric; Velasco, David [Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad s/n, 62210 Cuernavaca, Mor. (Mexico); Lega, Elena, E-mail: jeffrey.fung@berkeley.edu [Université de la Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange UMR 7293, Nice (France)

    2017-03-01

    Planetary migration is inherently a three-dimensional (3D) problem, because Earth-size planetary cores are deeply embedded in protoplanetary disks. Simulations of these 3D disks remain challenging due to the steep resolution requirements. Using two different hydrodynamics codes, FARGO3D and PEnGUIn, we simulate disk–planet interaction for a one to five Earth-mass planet embedded in an isentropic disk. We measure the torque on the planet and ensure that the measurements are converged both in resolution and between the two codes. We find that the torque is independent of the smoothing length of the planet’s potential ( r {sub s}), and that it has a weak dependence on the adiabatic index of the gaseous disk ( γ ). The torque values correspond to an inward migration rate qualitatively similar to previous linear calculations. We perform additional simulations with explicit radiative transfer using FARGOCA, and again find agreement between 3D simulations and existing torque formulae. We also present the flow pattern around the planets that show active flow is present within the planet’s Hill sphere, and meridional vortices are shed downstream. The vertical flow speed near the planet is faster for a smaller r {sub s} or γ , up to supersonic speeds for the smallest r {sub s} and γ in our study.

  18. Scale Length of the Galactic Thin Disk

    Indian Academy of Sciences (India)

    This paper presents an analysis of the first 2MASS (The Two Micron All Sky Survey) sampler data as observed at lower Galactic latitude in our Galaxy. These new near-infrared data provide insight into the structure of the thin disk of our Galaxy, The interpretation of star counts and color distributions of stars in the ...

  19. Strength of Cracked Reinforced Concrete Disks

    DEFF Research Database (Denmark)

    Hoang, Cao Linh; Nielsen, Mogens Peter

    1999-01-01

    The paper deals with models, based on the theory of plasticity, to be used in strength assessments of reinforced concrete disks suffering from different kinds of cracking. Based on the assumption that the sliding strength of concrete is reduced in sections where cracks are located, solutions...

  20. Scale Length of the Galactic Thin Disk

    Indian Academy of Sciences (India)

    tribpo

    synthetic stellar population model, gives strong evidence that the Galactic thin disk density scale length, hR, ... be preferred to investigate the stellar distribution, specially at large distances from the. Sun. In this paper, we present ... city gradient according to age metallicity and age scale height relations. In the model, the key ...

  1. THE STELLAR KINEMATICS OF GALACTIC DISKS

    NARCIS (Netherlands)

    BOTTEMA, R

    Stellar velocity dispersion measurements of a sample of 12 galactic disks are summarized. The observed radial functionality is parameterized such that one dispersion value is assigned to each galaxy. Comparison of the galaxy dispersion with absolute magnitude and maximum rotation reveals that the

  2. The short circuit instability in protoplanetary disks

    DEFF Research Database (Denmark)

    Hubbard, A.; McNally, C.P.; Mac Low, M.M.

    2013-01-01

    We introduce a magneto-hydrodynamic instability which occurs, among other locations, in the inner, hot regions of protoplanetary disks, and which alters the way in which resistive dissipation of magnetic energy into heat proceeds. This instability can be likened to both an electrical short circui...

  3. Resolving the inner disk of UX Orionis

    Science.gov (United States)

    Kreplin, A.; Madlener, D.; Chen, L.; Weigelt, G.; Kraus, S.; Grinin, V.; Tambovtseva, L.; Kishimoto, M.

    2016-05-01

    Aims: The cause of the UX Ori variability in some Herbig Ae/Be stars is still a matter of debate. Detailed studies of the circumstellar environment of UX Ori objects (UXORs) are required to test the hypothesis that the observed drop in photometry might be related to obscuration events. Methods: Using near- and mid-infrared interferometric AMBER and MIDI observations, we resolved the inner circumstellar disk region around UX Ori. Results: We fitted the K-, H-, and N-band visibilities and the spectral energy distribution (SED) of UX Ori with geometric and parametric disk models. The best-fit K-band geometric model consists of an inclined ring and a halo component. We obtained a ring-fit radius of 0.45 ± 0.07 AU (at a distance of 460 pc), an inclination of 55.6 ± 2.4°, a position angle of the system axis of 127.5 ± 24.5°, and a flux contribution of the over-resolved halo component to the total near-infrared excess of 16.8 ± 4.1%. The best-fit N-band model consists of an elongated Gaussian with a HWHM ~ 5 AU of the semi-major axis and an axis ration of a/b ~ 3.4 (corresponding to an inclination of ~72°). With a parametric disk model, we fitted all near- and mid-infrared visibilities and the SED simultaneously. The model disk starts at an inner radius of 0.46 ± 0.06 AU with an inner rim temperature of 1498 ± 70 K. The disk is seen under an nearly edge-on inclination of 70 ± 5°. This supports any theories that require high-inclination angles to explain obscuration events in the line of sight to the observer, for example, in UX Ori objects where orbiting dust clouds in the disk or disk atmosphere can obscure the central star. Based on observations made with ESO telescopes at Paranal Observatory under program IDs: 090.C-0769, 074.C-0552.

  4. Radiation thermo-chemical models of protoplanetary disks I. Hydrostatic disk structure and inner rim

    NARCIS (Netherlands)

    Woitke, P.; Kamp, I.; Thi, W. -F.

    Context. Emission lines from protoplanetary disks originate mainly in the irradiated surface layers, where the gas is generally warmer than the dust. Therefore, interpreting emission lines requires detailed thermo-chemical models, which are essential to converting line observations into

  5. MODELING DUST EMISSION OF HL TAU DISK BASED ON PLANET–DISK INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Sheng; Ji, Jianghui [Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Li, Shengtai; Li, Hui [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Isella, Andrea [Rice University, Houston, TX (United States)

    2016-02-10

    We use extensive global two-dimensional hydrodynamic disk gas+dust simulations with embedded planets, coupled with three-dimensional radiative transfer calculations, to model the dust ring and gap structures in the HL Tau protoplanetary disk observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). We include the self-gravity of disk gas and dust components and make reasonable choices of disk parameters, assuming an already settled dust distribution and no planet migration. We can obtain quite adequate fits to the observed dust emission using three planets with masses of 0.35, 0.17, and 0.26 M{sub Jup} at 13.1, 33.0, and 68.6 AU, respectively. Implications for the planet formation as well as the limitations of this scenario are discussed.

  6. Consistent dust and gas models for protoplanetary disks. I. Disk shape, dust settling, opacities, and PAHs

    National Research Council Canada - National Science Library

    Woitke, P; Min, M; Pinte, C; Thi, W. -F; Kamp, I; Rab, C; Anthonioz, F; Antonellini, S; Baldovin-Saavea, C; Carmona, A; Dominik, C; Dionatos, O; Greaves, J; Güdel, M; Ilee, J. D; Liebhart, A; Ménard, F; Rigon, L; Waters, L. B. F. M; Aresu, G; Meijerink, R; Spaans, M

    2016-01-01

    ..., and line radiative transfer from optical to cm wavelengths. The first paper of this series focuses on the assumptions about the shape of the disk, the dust opacities, dust settling, and polycyclic aromatic hydrocarbons (PAHs...

  7. Biomechanical behavior of human intervertebral discs subjected to long lasting axial loading.

    Science.gov (United States)

    Koeller, W; Funke, F; Hartmann, F

    1984-01-01

    48 lumbar discs were tested; the creep tests lasted between 2 and 6 hours. All discs showed the known creep behavior, i.e. a decrease of height, rate of creep and axial deformability with time. In the first minutes of a test the viscoelastic behavior quickly alters so that the disc behaves more like an elastic body. Loss of mass normally observed after creep tests is due to loss of water. Creep behavior is reproducible if a disc has sufficiently recovered, i.e. if it has regained its initial height. Creep tests on "desiccated" discs revealed that creeping is possible without loss of water and recovery is possible without absorption of water. The type of loading (static or dynamic) has hardly any influence on the biomechanical behavior. Our results indicate, that creep and recovery are chiefly due to extension and contraction of the anular fibers and not to fluid flow.

  8. CN rings in full protoplanetary disks around young stars as probes of disk structure

    Science.gov (United States)

    Cazzoletti, P.; van Dishoeck, E. F.; Visser, R.; Facchini, S.; Bruderer, S.

    2018-01-01

    Aims: Bright ring-like structure emission of the CN molecule has been observed in protoplanetary disks. We investigate whether such structures are due to the morphology of the disk itself or if they are instead an intrinsic feature of CN emission. With the intention of using CN as a diagnostic, we also address to which physical and chemical parameters CN is most sensitive. Methods: A set of disk models were run for different stellar spectra, masses, and physical structures via the 2D thermochemical code DALI. An updated chemical network that accounts for the most relevant CN reactions was adopted. Results: Ring-shaped emission is found to be a common feature of all adopted models; the highest abundance is found in the upper outer regions of the disk, and the column density peaks at 30-100 AU for T Tauri stars with standard accretion rates. Higher mass disks generally show brighter CN. Higher UV fields, such as those appropriate for T Tauri stars with high accretion rates or for Herbig Ae stars or for higher disk flaring, generally result in brighter and larger rings. These trends are due to the main formation paths of CN, which all start with vibrationally excited H_2^* molecules, that are produced through far ultraviolet (FUV) pumping of H2. The model results compare well with observed disk-integrated CN fluxes and the observed location of the CN ring for the TW Hya disk. Conclusions: CN rings are produced naturally in protoplanetary disks and do not require a specific underlying disk structure such as a dust cavity or gap. The strong link between FUV flux and CN emission can provide critical information regarding the vertical structure of the disk and the distribution of dust grains which affects the UV penetration, and could help to break some degeneracies in the SED fitting. In contrast with C2H or c-C3H2, the CN flux is not very sensitive to carbon and oxygen depletion.

  9. THE VLA VIEW OF THE HL TAU DISK: DISK MASS, GRAIN EVOLUTION, AND EARLY PLANET FORMATION

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco-González, Carlos; Rodríguez, Luis F.; Galván-Madrid, Roberto [Instituto de Radioastronomía y Astrofísica UNAM, Apartado Postal 3-72 (Xangari), 58089 Morelia, Michoacán, México (Mexico); Henning, Thomas; Linz, Hendrik; Birnstiel, Til; Boekel, Roy van; Klahr, Hubert [Max-Planck-Institut für Astronomie Heidelberg, Königstuhl 17, D-69117 Heidelberg (Germany); Chandler, Claire J.; Pérez, Laura [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801-0387 (United States); Anglada, Guillem; Macias, Enrique; Osorio, Mayra [Instituto de Astrofísica de Andalucía (CSIC), Apartado 3004, E-18080 Granada (Spain); Flock, Mario [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Menten, Karl [Jansky Fellow of the National Radio Astronomy Observatory (United States); Testi, Leonardo [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching bei München (Germany); Torrelles, José M. [Institut de Ciències de l’Espai (CSIC-IEEC) and Institut de Ciències del Cosmos (UB-IEEC), Martí i Franquès 1, E-08028 Barcelona (Spain); Zhu, Zhaohuan, E-mail: c.carrasco@crya.unam.mx, E-mail: l.rodriguez@crya.unam.mx, E-mail: r.galvan@crya.unam.mx, E-mail: henning@mpia.de, E-mail: linz@mpia.de [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2016-04-10

    The first long-baseline ALMA campaign resolved the disk around the young star HL Tau into a number of axisymmetric bright and dark rings. Despite the very young age of HL Tau, these structures have been interpreted as signatures for the presence of (proto)planets. The ALMA images triggered numerous theoretical studies based on disk–planet interactions, magnetically driven disk structures, and grain evolution. Of special interest are the inner parts of disks, where terrestrial planets are expected to form. However, the emission from these regions in HL Tau turned out to be optically thick at all ALMA wavelengths, preventing the derivation of surface density profiles and grain-size distributions. Here, we present the most sensitive images of HL Tau obtained to date with the Karl G. Jansky Very Large Array at 7.0 mm wavelength with a spatial resolution comparable to the ALMA images. At this long wavelength, the dust emission from HL Tau is optically thin, allowing a comprehensive study of the inner disk. We obtain a total disk dust mass of (1–3) × 10{sup −3} M {sub ⊙}, depending on the assumed opacity and disk temperature. Our optically thin data also indicate fast grain growth, fragmentation, and formation of dense clumps in the inner densest parts of the disk. Our results suggest that the HL Tau disk may be actually in a very early stage of planetary formation, with planets not already formed in the gaps but in the process of future formation in the bright rings.

  10. MHD simulations of jet acceleration from Keplerian accretion disks. The effects of disk resistivity

    Science.gov (United States)

    Zanni, C.; Ferrari, A.; Rosner, R.; Bodo, G.; Massaglia, S.

    2007-07-01

    Context: Accretion disks and astrophysical jets are used to model many active astrophysical objects, such as young stars, relativistic stars, and active galactic nuclei. However, existing proposals for how these structures may transfer angular momentum and energy from disks to jets through viscous or magnetic torques do not yet provide a full understanding of the physical mechanisms involved. Thus, global stationary solutions have not explained the stability of these structures; and global numerical simulations that include both the disk and jet physics have so far been limited to relatively short time scales and narrow (and possibly astrophysically unlikely) ranges of viscosity and resistivity parameters that may be crucial to defining the coupling of the inflow-outflow dynamics. Aims: We present self-consistent, time-dependent simulations of supersonic jets launched from magnetized accretion disks, using high-resolution numerical techniques. In particular we study the effects of the disk's magnetic resistivity, parametrized through an α-prescription, in determining the properties of the inflow-outflow system. Moreover we analyze under which conditions steady state solutions of the type proposed in the self-similar models of Blandford & Payne can be reached and maintained in a self-consistent nonlinear stage. Methods: We used the resistive MHD FLASH code with adaptive mesh refinement (AMR), allowing us to follow the evolution of the structure on a long enough time scale to reach steady state. A detailed analysis of the initial configuration state is given. Results: We obtain the expected solutions within the axisymmetric (2.5 D) limit. Assuming a magnetic field around equipartition with the thermal pressure of the disk, we show how the characteristics of the disk-jet system, such as the ejection efficiency and the energetics, are affected by the anomalous resistivity acting inside the disk.

  11. Localization of natural modes of vibration in bladed disks

    Science.gov (United States)

    Bendiksen, O. O.; Valero, N. A.

    1987-01-01

    A study is presented of the mode localization phenomenon in imperfect blade-disk and blade-shroud-disk assemblies. The results indicate that unshrouded blades mounted on stiff disks are especially susceptible, and even small blade imperfections within manufacturing tolerances are likely to trigger mode localization. Increasing the interblade coupling by adding shrouds or reducing the disk stiffness greatly reduces the localization susceptiblity, although certain modes may still become localized if the shrouds are free to slip.

  12. Resolving the Disk-Halo Degeneracy using Planetary Nebulae

    Science.gov (United States)

    Aniyan, S.; Freeman, K. C.; Arnaboldi, M.; Gerhard, O.; Coccato, L.; Fabricius, M.; Kuijken, K.; Merrifield, M.

    2017-10-01

    The decomposition of the 21 cm rotation curve of galaxies into contribution from the disk and dark halo depends on the adopted mass to light ratio (M/L) of the disk. Given the vertical velocity dispersion (σ z ) of stars in the disk and its scale height (h z ), the disk surface density and hence the M/L can be estimated. Earlier works have used this technique to conclude that galaxy disks are submaximal. Here we address an important conceptual problem: star-forming spirals have an old (kinematically hot) disk population and a young cold disk population. Both of these populations contribute to the integrated light spectra from which σ z is measured. The measured scale height h z is for the old disk population. In the Jeans equation, σ z and h z must pertain to the same population. We have developed techniques to extract the velocity dispersion of the old disk from integrated light spectra and from samples of planetary nebulae. We present the analysis of the disk kinematics of the galaxy NGC 628 using IFU data in the inner regions and planetary nebulae as tracers in the outer regions of the disk. We demonstrate that using the scale height of the old thin disk with the vertical velocity dispersion of the same population, traced by PNe, results in a maximal disk for NGC 628. Our analysis concludes that previous studies underestimate the disk surface mass density by ~ 2, sufficient to make a maximal disk for NGC 628 appear like a submaximal disk.

  13. Fatores genéticos e ambientais envolvidos na degeneração do disco intervertebral Genetic and environmental factors involved on intervertebral disc degeneration

    Directory of Open Access Journals (Sweden)

    Francine Teresa Brioni Nunes

    2007-01-01

    Full Text Available A etiologia da degeneração do disco intervertebral (DDI ainda não está totalmente esclarecida. O gene do receptor da vitamina D (VDR tem sido apontado como um dos possíveis envolvidos no surgimento das discopatias. Por outro lado, este estudo relaciona pela primeira vez, a participação dos genes das glutatião transferases M1 e T1 (GSTT1 e GSTM1, responsáveis pela inativação dos componentes do cigarro, na DDI. Foi extraído DNA de leucócitos de 66 pacientes e 88 controles, pareados por gênero e idade. O polimorfismo VDR-FokI foi amplificado por reação em cadeia da polimerase (PCR seguido de restrição com a enzima FokI. Os polimorfismos das GSTT1/M1 foram determinados por meio da PCR multiplex. A história familial e a gravidade da doença se destacaram nos pacientes portadores do alelo f do gene VDR-FokI (P=0,000 e 0,0012, respectivamente. A idade de surgimento da doença mostrou-se precoce nos indivíduos com genótipo _/f (média de 26 anos. Foi encontrada associação do polimorfismo FokI com a degeneração precoce e gravidade da DDI, sendo que o hábito de fumar também interferiu nesse processo, independente da presença ou não do genótipo favorável para GSTT1/M1.The etiology of intervertebral disc degeneration (IDD has not been fully clarified yet. Vitamin D receptor’s gene (VDR has been suggested as one of the potential entities involved in disc pathologies onset. On the other hand, this study correlates, for the first time, glutathione transferases M1 and T1 genes (GSTT1 and GSTM1 participation, which are responsible for cigarette components’ inactivation, in IDD. DNA was extracted from leukocytes of 66 patients and 88 controls, paired by gender and age. The VDR-Fokl polymorphism was amplified by polymerase chain reaction (PCR followed by restriction with Fokl enzyme. GSTT1/M1 polymorphisms were determined by means of PCR multiplex. Family history and disease severity were highlighted in patients carrying the f

  14. Tomographic Sounding of Protoplanetary and Transitional Disks: Using Inner Disk Variability at Near to Mid-IR Wavelengths to Probe Conditions in the Outer Disk

    Science.gov (United States)

    Grady, C. A.; Sitko, M.L.

    2013-01-01

    Spitzer synoptic monitoring of young stellar associations has demonstrated that variability among young stars and their disks is ubiquitous. The Spitzer studies have been limited by target visibility windows and cover only a short temporal baseline in years. A complementary approach is to focus on stars chosen for high-value observations (e.g. high-contrast imaging, interferometry, or access to wavelengths which are difficult to achieve from the ground) where the synoptic data can augment the imagery or interferometry as well as probing disk structure. In this talk, we discuss how synoptic data for two protoplanetary disks, MWC 480 and HD 163296, constrain the dust disk scale height, account for variable disk illumination, and can be used to locate emission features, such as the IR bands commonly associated with PAHs in the disk, as part of our SOFIA cycle 1 study. Similar variability is now known for several pre-transitional disks, where synoptic data can be used to identify inner disks which are not coplanar with the outer disk, and which may be relicts of giant planet-giant planet scattering events. Despite the logistical difficulties in arranging supporting, coordinated observations in tandem with high-value observations, such data have allowed us to place imagery in context, constrained structures in inner disks not accessible to direct imagery, and may be a tool for identifying systems where planet scattering events have occurred.

  15. The Design of a High-Integrity Disk Management Subsystem

    NARCIS (Netherlands)

    Oey, M.A.

    2005-01-01

    This dissertation describes and experimentally evaluates the design of the Logical Disk, a disk management subsystem that guarantees the integrity of data stored on disk even after system failures, while still providing performance competitive to other storage systems. Current storage systems that

  16. Imaging polarimetry of protoplanetary disks: feasibility and usability

    NARCIS (Netherlands)

    Min, M.; Jeffers, S.V.; Rodenhuis, M.; Canovas, H.; Buenzli, E.; Keller, C.U.; Waters, L.B.F.M.; Dominik, C.

    2010-01-01

    Imaging polarimetry is one of the most promising tools to map the structure of faint protoplanetary disks. In order to assess the feasibility of imaging polarimetry of protoplanetary disks and the usability to answer the scientific questions in the field we perform numerical simulations of disks of

  17. Failure analysis and shock protection of external hard disk drive ...

    African Journals Online (AJOL)

    Technology for processing and storage of data in portable external storage hard disks has increasingly improved over the years. Currently, terabytes of data can be stored in one portable external storage hard disk drive. Storing such amount of data on a single disk on itself is a risk. Several instances of data lost by big ...

  18. failure analysis and shock protection of external hard disk drive

    African Journals Online (AJOL)

    user

    Technology for processing and storage of data in portable external storage hard disks has increasingly improved over the years. Currently, terabytes of data can be stored in one portable external storage hard disk drive. Storing such amount of data on a single disk on itself is a risk. Several instances of data lost by big ...

  19. Water Vapor in the Protoplanetary Disk of DG Tau

    NARCIS (Netherlands)

    Podio, L.; Kamp, I.; Codella, C.; Cabrit, S.; Nisini, B.; Dougados, C.; Sandell, G.; Williams, J. P.; Testi, L.; Thi, W. -F.; Woitke, P.; Meijerink, R.; Spaans, M.; Aresu, G.; Menard, F.; Pinte, C.

    2013-01-01

    Water is key in the evolution of protoplanetary disks and the formation of comets and icy/water planets. While high-excitation water lines originating in the hot inner disk have been detected in several T Tauri stars (TTSs), water vapor from the outer disk, where most water ice reservoirs are

  20. On the Solar System-Debris Disk Connecction

    OpenAIRE

    Moro-Martin, Amaya

    2007-01-01

    This paper emphasizes the connection between solar and extra-solar debris disks: how models and observations of the Solar System are helping us understand the debris disk phenomenon, and vice versa, how debris disks are helping us place our Solar System into context.

  1. Change of barometric pressure influences low back pain in patients with vacuum phenomenon within lumbar intervertebral disc.

    Science.gov (United States)

    Kasai, Yuichi; Takegami, Kenji; Uchida, Atsumasa

    2002-08-01

    The present study investigates whether changes in barometric pressure influence low back pain in patients with vacuum phenomenon within lumbar intervertebral discs. Twenty-four patients with low back pain were examined: 12 with vacuum phenomenon within the intervertebral discs (VP [+] group) and 12 without the vacuum phenomenon (VP [-] group). All patients consented to an evaluation of low back pain in a hyperbaric oxygen chamber. In the VP (+) group, low back pain became more severe in one patient when atmospheric pressure was elevated, and in eight patients when atmospheric pressure was decreased. In the VP (-) group, two patients experienced more severe low back pain when atmospheric pressure was decreased. Our study demonstrated that low back pain might be aggravated by atmosphere depression in patients with lumbar disease associated with the vacuum phenomenon.

  2. [Clinical study on analgesic effect of Huaisanzhen on the nerve root pain due to prolapse of lumbar intervertebral disc].

    Science.gov (United States)

    Zhou, You-Long; Liu, Yi-Jun; Chen, Jian-Hui; Hu, Bin; Zhang, Shi-Qing; Sun, Guo-Sheng

    2005-01-01

    To search for an effective therapy for the nerve root pain caused by prolapse of lumbar intervertebral disc. One hundred and ninety-two cases were randomly divided into a Huaisanzhen group of 96 cases, a drug control group of 48 cases and an acupuncture control group of 48 cases. The Huaisanzhen group were treated by Huaisanzhen therapy, the drug control group by intramuscular injection of aspirin-DL-lysine and the acupuncture control group by routine acupuncture. The time inducing analgesic effect was shorter, the effect-lasting time was longer, and the analgesic effect and the comprehensive therapeutic effect were better in the treatment group as compared with the two control groups with very significant differences (P prolapse of lumbar intervertebral disc.

  3. A computational study of intervertebral disc degeneration in relation to changes in regional tissue composition and disc nutrition

    OpenAIRE

    Ruiz Wills, Carlos

    2015-01-01

    Up to 85% of the world population suffers from low back pain, a clinical condition often related to the intervertebral disc (IVD) degeneration (DD). Altered disc cell nutrition affects cell viability and can generate catabolic cascades that degrade the extracellular matrix (ECM). Also, a major degenerative biochemical change in the disc is the proteoglycan (PG) loss, which affects the osmotic pressure and hydration that is critical for cell nutrition. However, the relationship between biochem...

  4. Soft Stabilization With an Artificial Intervertebral Ligament in Grade I Degenerative Spondylolisthesis: Comparison With Instrumented Posterior Lumbar Interbody Fusion

    OpenAIRE

    Shim, Chan Shik; Lee, Sang-Ho; Park, Sun-Hee; Whang, Ji-Hee

    2007-01-01

    Background The purpose of this retrospective study was to evaluate the efficacy of soft stabilization with an artificial intervertebral ligament after microdecompression for the treatment of grade I degenerative spondylolisthesis. Methods From a total of 54 patients with degenerative spondylolisthesis who were treated surgically from May 2000 to April 2003, 36 patients who showed grade I spondylolisthesis without evidence of concomitant disc herniation necessitating discectomy were enrolled i...

  5. Inflammatory and catabolic signalling in intervertebral discs: The roles of NF-B and MAP Kinases

    OpenAIRE

    K Wuertz; N Vo; D Kletsas; N Boos

    2012-01-01

    Painful intervertebral disc disease is characterised not only by an imbalance between anabolic (i.e., matrix synthesis) and catabolic (i.e., matrix degradation) processes, but also by inflammatory mechanisms. The increased expression and synthesis of matrix metalloproteinases and inflammatory factors is mediated by specific signal transduction, in particular the nuclear factor-kappaB (NF-kB) and mitogen-activated protein kinase (MAPK)-mediated pathways. NF-kB and MAPK have been identified as ...

  6. THE NATURE OF TRANSITION CIRCUMSTELLAR DISKS. II. SOUTHERN MOLECULAR CLOUDS

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Gisela A.; Schreiber, Matthias R.; Rebassa-Mansergas, Alberto [Departamento de Fisica y Astronomia, Universidad de Valparaiso, Valparaiso (Chile); Cieza, Lucas A. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Merin, Bruno [Herschel Science Centre, ESAC (ESA), P.O. Box 78, 28691 Villanueva de la Canada, Madrid (Spain); Smith Castelli, Analia V. [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Rivadavia 1917, C1033AAJ Buenos Aires (Argentina); Allen, Lori E. [Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721-0065 (United States); Morrell, Nidia [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile)

    2012-04-10

    Transition disk objects are pre-main-sequence stars with little or no near-IR excess and significant far-IR excess, implying inner opacity holes in their disks. Here we present a multifrequency study of transition disk candidates located in Lupus I, III, IV, V, VI, Corona Australis, and Scorpius. Complementing the information provided by Spitzer with adaptive optics (AO) imaging (NaCo, VLT), submillimeter photometry (APEX), and echelle spectroscopy (Magellan, Du Pont Telescopes), we estimate the multiplicity, disk mass, and accretion rate for each object in our sample in order to identify the mechanism potentially responsible for its inner hole. We find that our transition disks show a rich diversity in their spectral energy distribution morphology, have disk masses ranging from {approx}<1 to 10 M{sub JUP}, and accretion rates ranging from {approx}<10{sup -11} to 10{sup -7.7} M{sub Sun} yr{sup -1}. Of the 17 bona fide transition disks in our sample, three, nine, three, and two objects are consistent with giant planet formation, grain growth, photoevaporation, and debris disks, respectively. Two disks could be circumbinary, which offers tidal truncation as an alternative origin of the inner hole. We find the same heterogeneity of the transition disk population in Lupus III, IV, and Corona Australis as in our previous analysis of transition disks in Ophiuchus while all transition disk candidates selected in Lupus V, VI turned out to be contaminating background asymptotic giant branch stars. All transition disks classified as photoevaporating disks have small disk masses, which indicates that photoevaporation must be less efficient than predicted by most recent models. The three systems that are excellent candidates for harboring giant planets potentially represent invaluable laboratories to study planet formation with the Atacama Large Millimeter/Submillimeter Array.

  7. Herschel-PACS observation of the 10 Myr old T Tauri disk TW Hya : Constraining the disk gas mass

    NARCIS (Netherlands)

    Thi, W. -F.; Mathews, G.; Menard, F.; Woitke, P.; Meeus, G.; Riviere-Marichalar, P.; Pinte, C.; Howard, C. D.; Roberge, A.; Sandell, G.; Pascucci, I.; Riaz, B.; Grady, C. A.; Dent, W. R. F.; Kamp, I.; Duchene, G.; Augereau, J. -C.; Pantin, E.; Vandenbussche, B.; Tilling, I.; Williams, J. P.; Eiroa, C.; Barrado, D.; Alacid, J. M.; Andrews, S.; Ardila, D. R.; Aresu, G.; Brittain, S.; Ciardi, D. R.; Danchi, W.; Fedele, D.; de Gregorio-Monsalvo, I.; Heras, A.; Huelamo, N.; Krivov, A.; Lebreton, J.; Liseau, R.; Martin-Zaidi, C.; Mendigutia, I.; Montesinos, B.; Mora, A.; Morales-Calderon, M.; Nomura, H.; Phillips, N.; Podio, L.; Poelman, D. R.; Ramsay, S.; Rice, K.; Solano, E.; White, G. J.; Wright, G.; Walker, H.

    2010-01-01

    Planets are formed in disks around young stars. With an age of similar to 10 Myr, TW Hya is one of the nearest T Tauri stars that is still surrounded by a relatively massive disk. In addition a large number of molecules has been found in the TW Hya disk, making TW Hya the perfect test case in a

  8. A systematic approach to clinical determinations of causation in symptomatic spinal disk injury following motor vehicle crash trauma.

    Science.gov (United States)

    Freeman, Michael D; Centeno, Christopher J; Kohles, Sean S

    2009-10-01

    Clinical determinations of causation in cases of intervertebral disk (IVD) injury after a motor vehicle crash (MVC) are often disputed in medicolegal settings. No published systematic guidelines exist for making such determinations, which has resulted in infringement by nonclinical personnel into injury causation evaluations, a traditionally clinical activity. The result is causal determinations that are potentially disconnected from clinical observations of injury. The purpose of this review was to evaluate the current literature on causation, causal determinations after trauma and IVD injury after MVC, and to develop a practicable, logical, and literature-based approach to causation determinations of symptomatic IVD injury after MVC. The results of the review indicate IVD injury can result from any MVC regardless of magnitude, thus meeting the first criteria of causation, biologic plausibility. Individual determinations of causation depend entirely on the temporal association between the collision and the symptom onset (the second criterion) and a lack of a more probable explanation for the symptoms (the third). When these causal elements are met, clinicians can assert causation on a "more probable than not" or "reasonable probability" basis. Because of a lack of an established or reliable relationship between collision force and the probability of IVD injury the investigation of collision parameters is not a useful adjunct to causal determinations.

  9. Molecular profile of major growth factors in lumbar intervertebral disc herniation: Correlation with patient clinical and epidemiological characteristics.

    Science.gov (United States)

    Tsarouhas, Alexandros; Soufla, Giannoula; Tsarouhas, Konstantinos; Katonis, Pavlos; Pasku, Dritan; Vakis, Antonis; Tsatsakis, Aristides M; Spandidos, Demetrios A

    2017-04-01

    The involvement of growth factors (GFs) in the pathogenesis of lumbar intervertebral disc (ID) herniation and the spontaneous resorption of herniated ID fragments remains only partially elucidated. A simultaneous assessment of the transcript levels of numerous GFs and their association with clinical and epidemiological profiles of human ID herniation would provide valuable insight into the biology and clinical course of the disease. In the present study, we examined simultaneously the transcript levels of vascular endothelial growth factor (VEGF), transforming growth factor β1 (TGF‑β1), basic fibroblast growth factor 2 (bFGF2), platelet derived growth factor (PDGF) isoforms and receptors, epidermal growth factor (EGF) and insulin growth factor‑1 (IGF‑1) in herniated and control ID specimens and investigated their correlation with the clinicopathological profiles of patients suffering from symptomatic lumbar ID herniation. GF mRNA expression levels were determined by RT-qPCR in 63 surgical specimens from lumbar herniated discs and 10 control ID specimens. Multiple positive correlations were observed between the transcript levels of the GFs examined in the ID herniation group. VEGF mRNA expression was significantly increased in the protruding compared with the extruded discs. Intense and acute pain significantly upregulated the PDGF transcript levels. Significant negative correlations were observed between the patient body mass index and the transcript levels of VEGF and PDGF receptors. Our findings support the hypothesis of the involvement of GFs in the natural history of ID herniation. GFs synergistically act in herniated IDs. Increased VEGF expression possibly induces the neovascularization process in the earliest stages of ID herniation. PDGF‑C and ‑D play a role in the acute phase of radiculopathy in a metabolic response for tissue healing. A molecular effect, in addition to the biomechanical effect of obesity in the

  10. Nonsurgical Treatment Choices by Individuals with Lumbar Intervertebral Disc Herniation in the United States: Associations with Long-term Outcomes.

    Science.gov (United States)

    Thackeray, Anne; Fritz, Julie M; Lurie, Jon D; Zhao, Wenyan; Weinstein, James N

    2017-08-01

    The objectives of this study were to (1) evaluate differences between patients with lumbar intervertebral disc herniation who received physical therapy (PT) and those who did not; (2) identify factors associated with receiving PT; and (3) examine the influence of PT on clinical outcomes over the course of 1 yr. An observational cohort study using data from the Spine Patient Outcomes Research Trial was conducted. This study included 363 patients with intervertebral disc herniation who received nonsurgical management within 6 wks of enrollment. Baseline characteristics were compared between patients who received PT and those who did not. Multivariate logistic regression examined factors predictive of patients receiving PT. Mixed effects models were used to compare primary outcomes (Short-Form Survey 36 bodily pain and physical function and modified Oswestry Index) at 3 and 6 mos and 1 yr after enrollment. Forty percent of the nonsurgical cohort received PT. Higher disability scores, neurological deficit, and patient preference predicted PT use. Compared with other nonsurgical management strategies, standard care PT was not associated with a significant difference in pain, disability, or surgery over 1 yr. Many patients with intervertebral disc herniation seek secondary care for persisting symptoms and pursue nonsurgical management. The best management strategy is unclear and further research is needed to examine appropriate sequencing and selection of treatment.

  11. Intra- and inter-observer reliability of MRI examination of intervertebral disc abnormalities in patients with cervical myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Braga-Baiak, Andresa [Center for Excellence in Surgical Outcomes, Duke University Medical Center, Durham, NC (United States); Post-graduation Program, Department of Radiology, University of Sao Paulo (Brazil); Shah, Anand [Center for Excellence in Surgical Outcomes, Duke University Medical Center, Durham, NC (United States); Pietrobon, Ricardo [Center for Excellence in Surgical Outcomes, Duke University Medical Center, Durham, NC (United States); Department of Surgery, Duke University Medical Center, Durham, NC (United States); Braga, Larissa [Center for Excellence in Surgical Outcomes, Duke University Medical Center, Durham, NC (United States); University of Nebraska Medical Center, Lincoln NE (United States); Neto, Arnolfo Carvalho [Clinica DAPI, Curitiba (Brazil); Section of Diagnostic Radiology, Department of Internal Medicine, Universidade Federal do Parana (Brazil); Cook, Chad [Center for Excellence in Surgical Outcomes, Duke University Medical Center, Durham, NC (United States); Division of Physical Therapy, Duke University Medical Center, Durham, NC (United States)], E-mail: chad.cook@duke.edu

    2008-01-15

    Purpose: Intervertebral cervical disc herniation (CDH) is a relatively common disorder that can coexist with degenerative changes to worsen cervicogenic myelopathy. Despite the frequent disc abnormalities found in asymptomatic populations, magnetic resonance imaging (MRI) is considered excellent at detecting cervical spine myelopathy (CSM) associated with disc abnormality. The objective of this study was to investigate the intra- and inter-observer reliability of MRI detection of CSM in subjects who also had co-existing intervertebral disc abnormalities. Materials and methods: Seven experienced radiologists reviewed twice the MRI of 10 patients with clinically and/or imaging determined myelopathy. MRI assessment was performed individually, with and without operational guidelines. A Fleiss Kappa statistic was used to evaluate the intra- and inter-observer agreement. Results: The study found high intra-observer percent agreement but relatively low Kappa values on selected variables. Inter-observer reliability was also low and neither observation was improved with operational guidelines. We believe that those low values may be associated with the base rate problem of Kappa. Conclusion: In conclusion, this study demonstrated high intra-observer percent agreement in MR examination for intervertebral disc abnormalities in patients with underlying cervical myelopathy, but differing levels of intra- and inter-observer Kappa agreement among seven radiologists.

  12. Quantitative in vivo MRI evaluation of lumbar facet joints and intervertebral discs using axial T2 mapping

    Energy Technology Data Exchange (ETDEWEB)

    Stelzeneder, David; Messner, Alina; Scheurecker, Georg; Goed, Sabine; Friedrich, Klaus M.; Trattnig, Siegfried [Medical University of Vienna, Department of Radiology, MR Centre-High Field MR, Vienna (Austria); Vlychou, Marianna [Medical University of Vienna, Department of Radiology, MR Centre-High Field MR, Vienna (Austria); University Hospital of Larissa, Department of Radiology, Larissa (Greece); Welsch, Goetz H. [Medical University of Vienna, Department of Radiology, MR Centre-High Field MR, Vienna (Austria); University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Pieber, Karin; Pflueger, Verena [Medical University of Vienna, Department of Physical Medicine and Rehabilitation, Vienna (Austria)

    2011-11-15

    To assess the feasibility of T2 mapping of lumbar facet joints and intervertebral discs in a single imaging slab and to compare the findings with morphological grading. Sixty lumbar spine segments from 10 low back pain patients and 5 healthy volunteers were examined by axial T2 mapping and morphological MRI at 3.0 Tesla. Regions of interest were drawn on a single slice for the facet joints and the intervertebral discs (nucleus pulposus, anterior and posterior annulus fibrosus). The Weishaupt grading was used for facet joints and the Pfirrmann score was used for morphological disc grading (''normal'' vs. ''abnormal'' discs). The inter-rater agreement was excellent for the facet joint T2 evaluation (r = 0.85), but poor for the morphological Weishaupt grading (kappa = 0.15). The preliminary results show similar facet joint T2 values in segments with normal and abnormal Pfirrmann scores. There was no difference in mean T2 values between facet joints in different Weishaupt grading groups. Facet joint T2 values showed a weak correlation with T2 values of the posterior annulus (r = 0.32) This study demonstrates the feasibility of a combined T2 mapping approach for the facet joints and intervertebral discs using a single axial slab. (orig.)

  13. Measurement of Intervertebral Cervical Motion by Means of Dynamic X-Ray Image Processing and Data Interpolation

    Directory of Open Access Journals (Sweden)

    Paolo Bifulco

    2013-01-01

    Full Text Available Accurate measurement of intervertebral kinematics of the cervical spine can support the diagnosis of widespread diseases related to neck pain, such as chronic whiplash dysfunction, arthritis, and segmental degeneration. The natural inaccessibility of the spine, its complex anatomy, and the small range of motion only permit concise measurement in vivo. Low dose X-ray fluoroscopy allows time-continuous screening of cervical spine during patient’s spontaneous motion. To obtain accurate motion measurements, each vertebra was tracked by means of image processing along a sequence of radiographic images. To obtain a time-continuous representation of motion and to reduce noise in the experimental data, smoothing spline interpolation was used. Estimation of intervertebral motion for cervical segments was obtained by processing patient’s fluoroscopic sequence; intervertebral angle and displacement and the instantaneous centre of rotation were computed. The RMS value of fitting errors resulted in about 0.2 degree for rotation and 0.2 mm for displacements.

  14. Research on the Influence of the Properties of Intervertebral Disc Stiffness of the Lumbar Spine on the Displacement of Veretbrae

    Directory of Open Access Journals (Sweden)

    Artūras Linkel

    2015-03-01

    Full Text Available The article proposes the method for evaluating angular and linear changes in intervertebral discs of the spine depending on linear and nonlinear intervertebral disc stiffness. A dynamic made of 5 solid bodies connected by damping and stiffness components and applied for 2-D 10 degrees of freedom of the lumbar spine has been used for calculations. The system of the equation has been written in a matrix form. Lumbar intervertebral discs stiffness and damping properties have been selected from scientific articles and make from 200 N/mm to 1200 N/mm and from 229 Ns / mm to 5100 Ns/mm respectively for non-linear calculation and 800 N / mm – 2637 Ns/mm for linear displacement calculation. External loads applied to the model are 1648 N, 2957 N, 3863 N and 4542 N. The basic task of the paper is to calculate the biggest difference in linear and angular displacement considering 2 cases: linear and non-linear stiffness value. The greatest estimated difference, under the highest load, makes 0.6 mm for linear and 0.95 degrees for angular displacement. Because of the fast response of the model to the load, the damping value could not affect displacement.

  15. Surgical management of first caudal nerve root foraminal compression secondary to intervertebral disc disease in a Cocker Spaniel.

    Science.gov (United States)

    de Vicente, F; Pinilla, M; McConnell, J F; Bernard, F

    2012-01-01

    A nine-year-old spayed female Cocker Spaniel was investigated for an eight week history of licking and rubbing at the tail base, dullness, and signs of pain on manipulation of the tail. Left-sided intraforaminal compression of the first caudal nerve root due to intervertebral disc disease was diagnosed by radiographic, computed tomography, and magnetic resonance imaging examinations. The dog was nonresponsive to conservative medical therapy. A decompressive left-sided first-second caudal (Cd1-Cd2) foraminotomy was performed. Postoperative computed tomography confirmed surgical decompression of the involved nerve root. At the one month follow-up examination there was marked improvement in clinical signs. At two months, clinical signs were completely resolved and there was not any evidence of recurrence twelve months after surgery. Intervertebral disc disease should be considered as a differential diagnosis in dogs with discomfort at the tail base or signs of pain on manipulation of the tail. Surgical decompression may be indicated for management of these cases. This is the first report of diagnosis and surgical management of caudal intervertebral disc disease by foraminotomy in the dog. Surgical decompression by foraminotomy may therefore be a treatment option for this condition.

  16. Osteological and morphometric observations on intervertebral joints in the canine pre-diaphragmatic thoracic spine (Th1-Th9).

    Science.gov (United States)

    Breit, S

    2002-11-01

    The incidence of facet aplasia was investigated in three groups of pure-bred dogs. We examined large breeds (Rough Collies, Doberman Pinschers, Rottweilers, Bernese Mountain Dogs, German Shepherd Dogs), chondrodystrophic breeds (Dachshunds, Pekinese dogs), and small breeds (Yorkshire Terriers, Maltese dogs). Uni- or bilateral aplasia of zygapophyseal (facet) joints was exclusively found in juvenile and adult small dogs, in which the incidence of aplasia ranged from between 26% (Th1) and 63% (Th8). There was no evidence that aplasia of zygapophyseal joints increases the risk of developing intervertebral disc disease or deformative spondylosis in small breeds. By applying the findings of previous empirical studies on intervertebral disc geometry and its biomechanical behaviour on the present morphometric results, there was an indication that the intervertebral disc may well compensate for the functional loss of aplastic zygapophyseal joints in small dogs. Biomechanical factors and their potential role as inducing agents of facet aplasia in the pre-diaphragmatic thoracic spine are also discussed. Copyright 2002 Published by Elsevier Science Ltd.

  17. Validation of genome-wide intervertebral disc calcification associations in Dachshund and further investigation of the chromosome 12 susceptibility locus

    Directory of Open Access Journals (Sweden)

    Mette Sloth eMogensen

    2012-11-01

    Full Text Available Herniation of the intervertebral disc is a common cause of neurological dysfunction in the dog, particularly in the Dachshund. Using the Illumina CanineHD BeadChip, we have previously identified a major locus on canine chromosome 12 nucleotide positions 36,750,205-38,524,449 that strongly associates with intervertebral disc calcification in Danish wire-haired Dachshunds. In this study, targeted resequencing identified two synonymous variants in MB21D1 and one in the 5’-untranslated region of KCNQ5 that associates with intervertebral disc calcification in an independent sample of wire-haired Dachshunds. Haploview identified seven linkage disequilibrium blocks across the disease associated region. The effect of haplotype windows on disc calcification shows that all haplotype windows are significantly associated with disc calcification. However, our predictions imply that the causal variant(s are most likely to be found between nucleotide 36,750,205-37,494,845 as this region explains the highest proportion of variance in the dataset. Finally, we develop a risk prediction model for wire-haired Dachshunds.We validated the association of the chromosome 12 locus with disc calcification in an independent sample of wire-haired Dachshunds and identify potential risk variants. Additionally, we estimated haplotype effects and set up a model for prediction of disc calcifications in wire-haired dachshunds based on genotype data. This genetic prediction model may prove useful in selection of breeding animals in future breeding programs

  18. [The synergistic effect of amygdalin and HSYA on the IL-1beta induced endplate chondrocytes of rat intervertebral discs].

    Science.gov (United States)

    Niu, Kai; Zhao, Yong-Jian; Zhang, Lei; Li, Chen-Guang; Wang, Yong-Jun; Zheng, Wei-Chao

    2014-08-01

    The effect of amygdalin joint hydroxysafflor yellow A (HSYA) on the endplate chondrocytes derived from intervertebral discs of rats induced by IL-1beta and the possible mechanism were studied and explored. Chondrocytes were obtained from endplate of one-month SD rat intervertebral discs and cultured primary endplate chondrocytes. After identification, they were divided into normal group, induced group, amygdalin group, HSYA group and combined group. CCK-8 kit was adopted to detect the proliferation of the endplate chondrocytes. FCM was measured to detect the apoptosis. Real-time PCR method was adopted to observe the mRNA expression of Aggrecan, Col 2 alpha1, Col 10 alpha1, MMP-13 and the inflammatory cytokines IL-1beta. The protein expression of Col II, Col X was tested through immunofluorescence. Compared with the normal group, the proliferation of the endplate chondrocytes decreased while the apoptosis increased (P amygdalin group, HSYA group, the combined group could inhibit the apoptosis and promote the proliferation (P amygdalin and HSYA. Amygdalin joint HSYA could inhibit the degeneration of the endplate chondrocytes derived from intervertebral discs of rats induced by IL-1beta and better than the single use of amygdalin or HSYA.

  19. Distraction-fusion for caudal cervical spondylomyelopathy using an intervertebral cage and locking plates in 14 dogs.

    Science.gov (United States)

    Steffen, Frank; Voss, Katja; Morgan, Joe P

    2011-08-01

    To evaluate clinical and radiographic outcome in dogs with caudal cervical spondylomyelopathy (CCSM) treated with an intervertebral fusion cage and locking plates. Prospective clinical study. Large breed dogs (n=14) with CCSM. Dogs had single level cervical spine distraction/fusion performed using an intervertebral cage with a hollow center filled with cancellous autograft and 2 ventrally applied locking plates. Outcome was measured using neurologic scores and radiographic interpretation 6 weeks, 6 months, and 12 months postoperatively. The surgical procedure was well tolerated in all dogs. Final outcome at 12 months was available in 9 dogs. Five dogs were judged excellent, 1 dog was good, 2 dogs were satisfactory, and 2 dogs were poor because of adjacent segment disease. Four dogs died for reasons unrelated to the procedure. Radiographically, implants remained stable over the entire follow-up period. The disc space continued to fill with an immature pattern of new bone, which showed progressive increase in opacity and quantity. Subsidence of the cage (median 2 m) was detected in 9 dogs at 6 weeks and remained unchanged in those that could be followed further. Distraction-fusion of single level CCSM in dogs with a combination of intervertebral cage and ventral locking plates is clinically effective and results in successful bony fusion. © Copyright 2011 by The American College of Veterinary Surgeons.

  20. Localized venous plexi in the spine simulating prolapse of an intervertebral disc: a report of six cases.

    Science.gov (United States)

    Hammer, Alan; Knight, Ian; Agarwal, Anand

    2003-01-01

    Six cases are reported in which the clinical presentation of a prolapsed intervertebral disc was found to be caused by a localized venous plexus. To emphasize the fact that the clinical presentation of a localized plexus of epidural veins in the lumbar spine can resemble that of an acute disc prolapse. The finding of enlarged epidural veins during lumbar disc decompression is relatively common, but it is only recently that they have been implicated as the cause of the presenting symptoms. Six individuals presented with severe pain in the lower back accompanied by sciatica, which had begun acutely. Physical examination in most of these patients showed the presence of neurologic signs in the affected leg. The initial clinical assessment was that of an acute prolapse of a lumbar disc. This diagnosis appeared to be borne out by the MRI scans, which demonstrated a "prolapsed disc" at the relevant level of the spine. However, at surgery, the intervertebral disc appeared to be relatively normal, but at the spine was found a large, localized plexus of epidural veins whose configuration matched the MRI image. The symptoms were relieved by decompression of the spine and ablation of the veins. Any pathologic process in the lumbar spine compressing a nerve root can cause localized pain in the back accompanied by sciatica. Most of these conditions can be differentiated by means of an MRI scan. The MRI image of a localized plexus of epidural veins, however, closely resembles that of a prolapsed intervertebral disc, which may be diagnostically misleading.

  1. Constraining a Thin Dark Matter Disk with Gaia

    OpenAIRE

    Schutz, Katelin; Lin, Tongyan; Safdi, Benjamin R.; Wu, Chih-Liang

    2017-01-01

    If a component of the dark matter has dissipative interactions, it could collapse to form a thin dark disk in our Galaxy that is coplanar with the baryonic disk. It has been suggested that dark disks could explain a variety of observed phenomena, including periodic comet impacts. Using the first data release from the Gaia space observatory, we search for a dark disk via its effect on stellar kinematics in the Milky Way. Our new limits disfavor the presence of a thin dark matter disk, and we p...

  2. Reading the Signatures of Extrasolar Planets in Debris Disks

    Science.gov (United States)

    Kuchner, Marc J.

    2009-01-01

    An extrasolar planet sculpts the famous debris dish around Fomalhaut; probably ma ny other debris disks contain planets that we could locate if only we could better recognize their signatures in the dust that surrounds them. But the interaction between planets and debris disks involves both orbital resonances and collisions among grains and rocks in the disks --- difficult processes to model simultanemus]y. I will describe new 3-D models of debris disk dynamics that incorporate both collisions and resonant trapping of dust for the first time, allowing us to decode debris disk images and read the signatures of the planets they contain.

  3. TW Hydrae: multi-wavelength interferometry of a transition disk

    Science.gov (United States)

    Menu, J.; van Boekel, R.; Henning, T.; Benisty, M.; Chandler, C. J.; Linz, H.; Waelkens, C.; Andrews, S. M.; Calvet, N.; Carpenter, J. M.; Corder, S. A.; Deller, A. T.; Dullemond, C. P.; Greaves, J. S.; Harris, R. J.; Isella, A.; Kwon, W.; Lazio, J.; Mundy, L. G.; Perez, L. M.; Ricci, L.; Sargent, A. I.; Storm, S.; Testi, L.; Wilner, D. J.

    2014-01-01

    For over a decade, the structure of the inner ``hole'' in the transition disk around TW Hydrae has been a subject of debate. To probe the innermost regions of the protoplanetary disk, observations at the highest possible spatial resolution are required. We present new interferometric data of TW Hya from near-infrared to millimeter wavelengths. We confront existing models of the disk structure with the complete data set and develop a new, detailed radiative-transfer model. This model is characterized by: 1) a spatial separation of the largest grains from the small disk grains; and 2) a smooth inner rim structure, rather than a sharp disk edge.

  4. Neutron fluence spectrometry using disk activation

    Energy Technology Data Exchange (ETDEWEB)

    Loevestam, Goeran [EC-JRC-Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium)], E-mail: goeran.loevestam@ec.europa.eu; Hult, Mikael; Fessler, Andreas; Gasparro, Joel; Kockerols, Pierre; Okkinga, Klaas [EC-JRC-Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium); Tagziria, Hamid [EC-JRC-Institute for the Protection and the Security of the Citizen (IPSC), Via E. Fermi 1, I-21020 Ispra (Vatican City State, Holy See,) (Italy); Vanhavere, Filip [SCK-CEN, Boeretang, 2400 Mol (Belgium); Wieslander, J.S. Elisabeth [EC-JRC-Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, B-2440 Geel (Belgium); Department of Physics, P.O. Box 35 (YFL), FIN-40014, University of Jyvaeskylae (Finland)

    2009-01-15

    A simple and robust detector for spectrometry of environmental neutrons has been developed. The technique is based on neutron activation of a series of different metal disks followed by low-level gamma-ray spectrometry of the activated disks and subsequent neutron spectrum unfolding. The technique is similar to foil activation but here the applied neutron fluence rates are much lower than usually in the case of foil activation. The detector has been tested in quasi mono-energetic neutron fields with fluence rates in the order of 1000-10000 cm{sup -2} s{sup -1}, where the obtained spectra showed good agreement with spectra measured using a Bonner sphere spectrometer. The detector has also been tested using an AmBe source and at a neutron fluence rate of about 40 cm{sup -2} s{sup -1}, again, a good agreement with the assumed spectrum was achieved.

  5. Collinear technology for a holographic versatile disk

    Science.gov (United States)

    Horimai, Hideyoshi; Tan, Xiaodi

    2006-02-01

    A novel reading and writing technology for a holographic versatile disk (HVD) system called collinear technology is developed. With this method a two-dimensional data page can be recorded as volumetric holograms generated by a reference beam and a signal beam that are bundled on the same axis and that are irradiated on the recording medium through a single objective lens. The multiplex recording and reconstruction process is demonstrated, and it is shown that the optical configuration and the dichroic medium disk structure are suitable for a compact system. With the HVD's special structure, the system can use a servo to focus, track, and locate the reading and writing addresses. A unique selectable-capacity recording format of a HVD and its standardization activity are also introduced. This method will enable us to construct a small HVD system with CD and DVD upper compatibilities.

  6. Dead Zone Accretion Flows in Protostellar Disks

    Science.gov (United States)

    Turner, Neal; Sano, T.

    2008-01-01

    Planets form inside protostellar disks in a dead zone where the electrical resistivity of the gas is too high for magnetic forces to drive turbulence. We show that much of the dead zone nevertheless is active and flows toward the star while smooth, large-scale magnetic fields transfer the orbital angular momentum radially outward. Stellar X-ray and radionuclide ionization sustain a weak coupling of the dead zone gas to the magnetic fields, despite the rapid recombination of free charges on dust grains. Net radial magnetic fields are generated in the magnetorotational turbulence in the electrically conducting top and bottom surface layers of the disk, and reach the midplane by ohmic diffusion. A toroidal component to the fields is produced near the midplane by the orbital shear. The process is similar to the magnetization of the solar tachocline. The result is a laminar, magnetically driven accretion flow in the region where the planets form.

  7. Residual stresses in Inconel 718 engine disks

    Directory of Open Access Journals (Sweden)

    Dahan Yoann

    2014-01-01

    Full Text Available Aubert&Duval has developed a methodology to establish a residual stress model for Inconel 718 engine discs. To validate the thermal, mechanical and metallurgical parts of the model, trials on lab specimens with specific geometry were carried out. These trials allow a better understanding of the residual stress distribution and evolution during different processes (quenching, ageing, machining. A comparison between experimental and numerical results reveals the residual stresses model accuracy. Aubert&Duval has also developed a mechanical properties prediction model. Coupled with the residual stress prediction model, Aubert&Duval can now propose improvements to the process of manufacturing in Inconel 718 engine disks. This model enables Aubert&Duval customers and subcontractors to anticipate distortions issues during machining. It could also be usedt to optimise the engine disk life.

  8. Line-Driven Ablation of Circumstellar Disks

    Science.gov (United States)

    Kee, Nathaniel Dylan; Owocki, Stan; Kuiper, Rolf; Sundqvist, Jon

    2017-11-01

    Mass is a key parameter in understanding the evolution and eventual fate of hot, luminous stars. Mass loss through a wind driven by UV-scattering forces is already known to reduce the mass of such stars by 10-10 - 10-4 M⊙/yr over the course of their lifetimes. However, high-mass stars already drive such strong winds while they are still in their accretion epoch. Therefore, stellar UV-scattering forces will efficiently ablate material off the surface of their circumstellar disks, perhaps even shutting off the final accretion through the last several stellar radii and onto a massive protostar. By using a three-dimensional UV-scattering prescription, we here quantify the role of radiative ablation in controlling the disk's accretion rate onto forming high-mass stars. Particular emphasis is given to the potential impact of this process on the stellar upper mass limit.

  9. Effective gluon interactions from superstring disk amplitudes

    Energy Technology Data Exchange (ETDEWEB)

    Oprisa, D.

    2006-05-15

    In this thesis an efficient method for the calculation of the N-point tree-level string amplitudes is presented. Furthermore it is shown that the six-gluon open-superstring disk amplitude can be expressed by a basis of six triple hypergeometric functions, which encode the full {alpha}' dependence. In this connection material for obtaining the {alpha}' expansion of these functions is derived. Hereby many Euler-Zagier sums are calculated including multiple harmonic series. (HSI)

  10. Cryogenic Yb: YAG Thin-Disk Laser

    Science.gov (United States)

    2016-09-09

    R2. The two mirrors are separated by the mirror separation, L. The higher order radial Gaussian modes and a Gaussian multimode beam grow in size...transverse modes oscillating. Yb at the center of the disk is inverted prior to the periphery. As the pump power increases more modes reach the threshold...coupler optic is in place in order to eliminate lasing. A 50µm multimode fiber is placed near the surface so as to capture emission emitted vertically

  11. Ocular ultrasound findings in optic disk melanocytoma

    Directory of Open Access Journals (Sweden)

    Andrés Lisker-Cervantes

    2017-11-01

    Conclusion: Melanocytomas are small, benign tumors that are highly assessable by ocular ultrasound when their elevation surpasses 0.5 mm. In our study, the internal reflectivity ranged from high to very high, unlike other malignancies such as choroidal melanoma which tend to present with low internal reflectivity. The avascularity of the tumor is a common finding. Ultrasound is a remarkable tool that helps detect benign characteristics in a pigmented optic disk tumor and helps establish a more reliable diagnosis.

  12. Debris disks in open stellar clusters

    Science.gov (United States)

    Gorlova, Nadiya Igorivna

    Indirect searches for planets (such as radial velocity studies) show that their formation may be quite common. The planets are however too small and faint to be seen against the glare of their host stars; therefore, their direct detection is limited to the nearest systems. Alternatively one can study planets by studying their "by-product"---dust. We see raw material available for planets around young stars, and debris dust around old stars betraying planet-induced activity. Dust has a larger surface area per unit mass compared with a large body; it can be spread over a larger solid angle, intercepting more starlight and emitting much more light via reprocessing. By studying dusty disks we can infer the presence of planets at larger distances. Here we present results of a survey conducted with the Spitzer Space Telescope of debris disks in three open clusters. With ages of 30--100 Myrs, these clusters are old enough that the primordial dust should have accreted into planetesimals, fallen onto the star, or been blown away due to a number of physical processes. The dust we observe must come from collisions or sublimation of larger bodies. The purpose of this study is to investigate the dust evolution in the terrestrial planet zone, analogous to the Zodiacal cloud in our Solar system. We are most sensitive to this zone because the peak of a 125 K black body radiation falls into the primary pass-band of our survey---24mm. We investigate the fraction and amount of the infra-red excesses around intermediate- to solar-mass stars in open stellar clusters with well defined ages. The results are analyzed in the context of disk studies at other wavelengths and ages, providing an understanding of the time-scale for disk dissipation and ultimately planet building and frequency.

  13. The SEEDS of Planet Formation: Observations of Transitional Disks

    Science.gov (United States)

    Grady, Carol A.

    2011-01-01

    As part of its 5-year study, the Strategic Exploration of Exoplanets and Disk Systems (SEEDS) has already observed a number of YSOs with circumstellar disks, including 13 0.5-8 Myr old A-M stars with indications that they host wide gaps or central cavities in their circumstellar disks in millimeter or far-IR observations, or from deficits in warm dust thermal emission. For 8 of the disks, the 0.15" inner working angle of HiCIAO+A0188 samples material in the millimeter or mid-IR identified cavity. In one case we report detection of a previously unrecognized wide gap. For the remaining 4 stars, the SEEDS data sample the outer disk: in 3 cases, we present the first NIR imagery of the disks. The data for the youngest sample members 1-2 Myr) closely resemble coeval primordial disks. After approximately 3 Myr, the transitional disks show a wealth of structure including spiral features, rings, divots, and in some cases, largely cleared gaps in the disks which are not seen in coeval primordial disks. Some of these structural features are predicted consequences of Jovian-mass planets having formed in the disk, while others are novel features. We discuss the implications for massive planet formation timescales and mechanisms.

  14. Weakly Accreting Circumplanetary Disks and Satellites in Resonant Orbits

    Science.gov (United States)

    Fujii, Yuri I.; Kobayashi, Hiroshi; Takahashi, Sanemichi Z.; Gressel, Oliver

    2017-10-01

    During the formation phase of gas giants, circumplanetary gaseous disks form around the planets. Circumplanetary disks are important not only for mass supply to gas giants but also for formation of regular satellites. The size-scale of circumplanetary disks is smaller than that of protoplanetary disks and this makes magnetic diffusion quicker. Thus, it is more difficult to sustain the magnetorotational instability (MRI) in circumplanetary disks. In the absence of significant angular momentum transport, continuous mass flow from the parental protoplanetary disk leads to the formation of a massive circumplanetary disk. We have developed an evolutionary disk model for this scenario and have estimated the orbital evolution of moons within the disk. In a certain temperature range, we find that inward migration of a satellite can be stopped by a disk structure resulting from the opacity transitions. We also find that the second and third migrating satellites can be captured in mean motion resonances. In this way, a compact system in Laplace resonance, which are similar to inner three bodies of Galilean satellites, can be formed in our disk models.

  15. MIGRATION TRAPS IN DISKS AROUND SUPERMASSIVE BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    Bellovary, Jillian M.; Low, Mordecai-Mark Mac; McKernan, Barry; Ford, K. E. Saavik [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, NY 10024 (United States)

    2016-03-10

    Accretion disks around supermassive black holes (SMBHs) in active galactic nuclei (AGNs) contain stars, stellar mass black holes, and other stellar remnants, which perturb the disk gas gravitationally. The resulting density perturbations exert torques on the embedded masses causing them to migrate through the disk in a manner analogous to planets in protoplanetary disks. We determine the strength and direction of these torques using an empirical analytic description dependent on local disk gradients, applied to two different analytic, steady-state disk models of SMBH accretion disks. We find that there are radii in such disks where the gas torque changes sign, trapping migrating objects. Our analysis shows that major migration traps generally occur where the disk surface density gradient changes sign from positive to negative, around 20–300R{sub g}, where R{sub g} = 2GM/c{sup 2} is the Schwarzschild radius. At these traps, massive objects in the AGN disk can accumulate, collide, scatter, and accrete. Intermediate mass black hole formation is likely in these disk locations, which may lead to preferential gap and cavity creation at these radii. Our model thus has significant implications for SMBH growth as well as gravitational wave source populations.

  16. WFIRST: CGI Detection and Characterization of Circumstellar Disks

    Science.gov (United States)

    Debes, John; Chen, Christine; Dawson, Bekki; Douglas, Ewan S.; Duchene, Gaspard; Jang-Condell, Hannah; hines, Dean C.; Lewis, Nikole K.; Macintosh, Bruce; Mazoyer, Johan; Meshkat, Tiffany; Nemati, Bijan; Patel, Rahul; Perrin, Marshall; Poteet, Charles; Pueyo, Laurent; Ren, Bin; Rizzo, Maxime; Roberge, Aki; Stark, Chris; Turnbull, Margaret

    2018-01-01

    The WFIRST Coronagraphic Instrument (CGI) will be capable of obtaining up to 5×10-9 contrast to an inner working angle of ~150 mas for a selection of medium band visible light filters using shaped pupil coronagraph and hybrid Lyot coronagraph designs. We present initial work at defining the scientific capabilities of the CGI with respect to different types of circumstellar disks, including warm exo-zodiacal disks, cold debris disks, and protoplanetary disks. With the above designs, CGI will be able to detect bright protoplanetary and debris disks with sizes of >100 AU beyond 500 pc. Additionally, it will be able to discover warm exozodiacal dust disks ten times more massive than that of the Solar System for over 100 nearby solar-type stars. Finally, it will be able to characterize resolved circumstellar dust disks in multiple filters of visible light, providing constraints on the size, shape, and composition of the dust.

  17. Orbital Evolution of Moons in Weakly Accreting Circumplanetary Disks

    Science.gov (United States)

    Fujii, Yuri I.; Kobayashi, Hiroshi; Takahashi, Sanemichi Z.; Gressel, Oliver

    2017-04-01

    We investigate the formation of hot and massive circumplanetary disks (CPDs) and the orbital evolution of satellites formed in these disks. Because of the comparatively small size-scale of the sub-disk, quick magnetic diffusion prevents the magnetorotational instability (MRI) from being well developed at ionization levels that would allow MRI in the parent protoplanetary disk. In the absence of significant angular momentum transport, continuous mass supply from the parental protoplanetary disk leads to the formation of a massive CPD. We have developed an evolutionary model for this scenario and have estimated the orbital evolution of satellites within the disk. We find, in a certain temperature range, that inward migration of a satellite can be stopped by a change in the structure due to the opacity transitions. Moreover, by capturing second and third migrating satellites in mean motion resonances, a compact system in Laplace resonance can be formed in our disk models.

  18. Pathogenesis and clinical implications of optic disk hemorrhage in glaucoma.

    Science.gov (United States)

    Suh, Min Hee; Park, Ki Ho

    2014-01-01

    The association between optic disk hemorrhage and glaucoma has been studied for many years. Recently, randomized clinical trials have confirmed that disk hemorrhage is a risk factor for development and progression of glaucoma. Disk hemorrhage is more commonly detected in open-angle glaucoma with normal tension than in open-angle glaucoma with high tension. Development of disk hemorrhage possibly is associated with the biomechanical properties of the lamina cribrosa and surrounding tissues, including the intraocular pressure (IOP)-cerebrospinal pressure gradient, arterial pressure, and venous pressure. Disk hemorrhage may be a marker of rapid glaucoma progression, in that localized subclinical structural change predisposes to disk hemorrhage, after which subsequent disease progression is accelerated, and recurrent optic disk hemorrhages are related to rapid structural progression of glaucomatous damage. IOP-lowering therapy can be helpful in halting post-hemorrhage glaucoma progression. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Research overview on vibration damping of mistuned bladed disk assemblies

    Directory of Open Access Journals (Sweden)

    Liang ZHANG

    2016-04-01

    Full Text Available Bladed disk assemblies are very important parts in auto engine and gas turbine, and is widely used in practical engineering. The mistuning existing commonly in the bladed disk assemblies can destroy the vibration characteristics of the bladed disk assemblies, which is one of the reasons for the high cycle fatigue failure of bladed disk assemblies, so it is necessary to research how to reduce the vibration of the bladed disk assemblies. On the basis of the review of relevant research at home and abroad, the mistuning vibration mechanism of the bladed disk assemblies is introduced, and the main technical methods of the vibration damping of bladed disk assemblies are reviewed, such as artificially active mistuning, collision damping, friction damping and optimization of the blade position. Some future research directions are presented.

  20. Axisymmetric instabilities between coaxial rotating disks

    Science.gov (United States)

    Pécheux, Jean; Foucault, E.

    2006-09-01

    This paper concerns the stability of the von Kármán swirling flow between coaxial disks. A linear stability analysis shows that for moderate Reynolds numbers (Re≤50) and for any rotation ratio sin[-1,1[ there is a radial location r_{pc} from which the self-similar von Kármán solutions become unstable to axisymmetric disturbances. When the disks are moderately counter-rotating (sin[-0.56,0[), two different disturbances (types I and II) appear at the same critical radius. A spatio-temporal analysis shows that, at a very short distance from this critical radius, the first disturbance (type I) becomes absolutely unstable whereas the second (type II) remains convectively unstable. Outside this range of aspect ratios, all the disturbances examined are found to be absolutely unstable. The flow between two coaxial rotating disks enclosed in a stationary sidewall is then numerically investigated. For sufficently large aspect ratios, the cavity flow is found to be globally unstable for axisymmetric disturbances similar to that calculated with the self-similar solutions. The flow in cavities with aspect ratios smaller than R {≈} 10.3 (and Re {≤} 50) is not destabilized by these axisymmetric disturbances. An experimental investigation conducted for a cavity with aspect ratio R {=} 15 confirms the numerical results. Axisymmetric disturbances similar to those calculated for the same cavity are detected and three-dimensional modes can also be observed near the sidewall.

  1. Disk-averaged synthetic spectra of Mars.

    Science.gov (United States)

    Tinetti, Giovanna; Meadows, Victoria S; Crisp, David; Fong, William; Velusamy, Thangasamy; Snively, Heather

    2005-08-01

    The principal goal of the NASA Terrestrial Planet Finder (TPF) and European Space Agency's Darwin mission concepts is to directly detect and characterize extrasolar terrestrial (Earthsized) planets. This first generation of instruments is expected to provide disk-averaged spectra with modest spectral resolution and signal-to-noise. Here we use a spatially and spectrally resolved model of a Mars-like planet to study the detectability of a planet's surface and atmospheric properties from disk-averaged spectra. We explore the detectability as a function of spectral resolution and wavelength range, for both the proposed visible coronograph (TPFC) and mid-infrared interferometer (TPF-I/Darwin) architectures. At the core of our model is a spectrum-resolving (line-by-line) atmospheric/surface radiative transfer model. This model uses observational data as input to generate a database of spatially resolved synthetic spectra for a range of illumination conditions and viewing geometries. The model was validated against spectra recorded by the Mars Global Surveyor-Thermal Emission Spectrometer and the Mariner 9-Infrared Interferometer Spectrometer. Results presented here include disk-averaged synthetic spectra, light curves, and the spectral variability at visible and mid-infrared wavelengths for Mars as a function of viewing angle, illumination, and season. We also considered the differences in the spectral appearance of an increasingly ice-covered Mars, as a function of spectral resolution, signal-to-noise and integration time for both TPF-C and TPFI/ Darwin.

  2. Herschel-PACS observation of the 10 Myr old T Tauri disk TW Hya: Constraining the disk gas mass

    OpenAIRE

    Thi, W.-F; Ardila,D. R.; Ciardi, D. R.

    2010-01-01

    Planets are formed in disks around young stars. With an age of ~10 Myr, TW Hya is one of the nearest T Tauri stars that is still surrounded by a relatively massive disk. In addition a large number of molecules has been found in the TWHya disk, making TWHya the perfect test case in a large survey of disks with Herschel–PACS to directly study their gaseous component. We aim to constrain the gas and dust mass of the circumstellar disk around TW Hya. We observed the fine-structure lines of [O_...

  3. Infrared Observational Studies of Gas Molecules in Disks

    Science.gov (United States)

    Salyk, C.

    2011-12-01

    There remain many fundamental unanswered questions about protoplanetary disks, including how (and if?) they form planets, how mass is transferred through the disk and onto the star, and how they ultimately disperse. Also, a major goal of protoplanetary disk studies is to understand the relationship between disk properties and the physical and chemical properties of planetary systems. IR molecular spectroscopy is a particularly powerful tool for probing the conditions and physical process in protoplanetary disks, which are too small and close to their parent stars to be imaged with ease. I will discuss the suite of infrared molecular transitions observed to date, which highlight the following three techniques of IR spectroscopy. Firstly, line shapes and strengths can be used as tracers of disk physics, including volatile condensation/evaporation, photo-processes, grain growth and turbulence. Secondly, observations of multiple molecular abundances provide constraints for disk chemical models, which may ultimately help explain the great diversity of planetary bodies. Finally, resolved line shapes and spectro-astrometry provide a means to study disk structure on extremely small size scales. Because IR observations are typically sensitive to radii of a few AU or smaller, the processes and structures being probed are relevant to the birth and growth of terrestrial and giant planets. Recent results that I will highlight include the discovery of a multitude of molecules in disks around sun-like stars (including H2O, OH, HCN, C2H2 and CO2), with detection rates that depend on stellar mass, constraints on gas mass and location in transitional disks, detection and characterization of `snow lines', measurements of inner disk rims, and detections of inner disk asymmetries. I will also discuss how IR spectroscopy will remain relevant even with the emergence of facilities such as ALMA, as it allows us to connect the conditions in terrestrial-planet-forming regions with those in

  4. [Treatment of lumbar intervertebral disc herniation and sciatica with percutaneous transforaminal endoscopic technique].

    Science.gov (United States)

    Jiang, Yi; Song, Hua-Wei; Wang, Dong; Yang, Ming-Lian

    2013-10-01

    To analyze the clinical effects of percutaneous transforaminal endoscopic technique in treating lumbar intervertebral disc herniation and sciatica. From June 2011 to January 2012,the clinical data of 46 patients with lumbar intervertebral disc herniation and sciatica underwent percutaneous transforaminal endoscopic technique were retrospectively analyzed. There were 28 males and 18 females,ranging in age from 11 to 77 years old with an average of (39.7_ 15.3) years old,20 cases were L5S1 and 26 cases were L4,5. All patients had the symptoms such as lumbago and sciatica and their straight-leg raising test were positive. Straight-leg raising test of patients were instantly repeated after operation;operative time,volume of blood loss,complication, length of stay and duration of back to work or daily life were recorded. The clinical effects were assessed according to the VAS,JOA and JOABPEQ score. All operations were successful,postoperative straight-leg raising test were all negative. Operative time,volume of blood loss,length of stay,duration of back to work or daily life,follow-up time were (93.0+/-28.0) min, (20.0+/-9.0)ml, (3.1+/-1.5) d, (11.6+/-4.2) d, (13.9+/-1.6) months,respectively. VAS score of lumbar before operation and at the 1st and 3rd,6th,12th month after operation were 5.3+/-1.2,1.9+/-1.1,1.0+/-0.8,0.9+/-0.8,0.8+/-0.6,respectively;VAS score of leg before operation and at the 1st and 3rd,6th,12th month after operation were 7.2+ 1.2,0.8+/-1.2,0.5+/-0.8,0.5+/-0.8,0.3+/-0.8,respectively. Five factors of JOABPEQ score,including lumbar pain,lumbar function, locomotor activity,social life viability and mental status,were respectively 27.0+/-30.6,37.3+/-27.4,38.5+/-26.6,33.0+/-13.7,55.4+/-19.0 before operation and 83.6+/-24.8,89.4+/-15.7,87.0+/-17.9,58.4+/-14.6,79.5+/-13.4 at final follow-up. Preoperative and postoperative JOA score were 9.1+/-2.6 and 27.3+/- 1.7, respectively. The postoperative VAS,JOA and JOABPEQ score had significantly improved (Psciatica

  5. Correlation between lumbar intervertebral disc height and lumbar spine sagittal alignment among asymptomatic Asian young adults.

    Science.gov (United States)

    Zhang, Feng; Zhang, Kai; Tian, Hai-Jun; Wu, Ai-Min; Cheng, Xiao-Fei; Zhou, Tang-Jun; Zhao, Jie

    2018-02-12

    To investigate the distribution and characteristics of the lumbar intervertebral disc height (IDH) in asymptomatic Asian population and to determine whether the lumbar IDH is related to the lumbar spine sagittal alignment. A cohort of 169 cases of asymptomatic volunteers was enrolled from January 2014 to July 2016. All participants underwent magnetic resonance imaging of the lumbar spine and panoramic radiography of the spine. Panoramic radiographs of the spine were taken to evaluate pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT) using Surgimap® software. Roussouly classification was utilized to categorize all subjects according to the four subtypes of sagittal alignment. The IDH was measured on the MRI mid-saggital section of the vertebral body. The relationships between lumbar IDH and spine-pelvic parameters were also assessed using the Spearman correlation analysis. The reference value ranges of IDH in asymptomatic Asian volunteers between L1/2, L2/3, L3/4, L4/5, and L5/S1 were (6.25, 10.99), (6.97, 12.08), (7.42, 13.3), (7.76, 14.57),and (7.11, 13.12) mm, respectively. Based on the above reference value, the high lumbar intervertebral space is defined as more than 14 mm. According to the Roussouly Classification, there are 33 cases in type I, 48 in type II, 66 in type III, and 22 in type IV. According to the definition of the high IDH, there are two cases in type I, three in type II, nine in type III, and eight in type IV. The results indicated that people in the Roussouly III and IV subtypes had greater values for IDH compared to those of Roussouly I and II subtypes, and the spinopelvic parameters were partly correlated with IDH in different subtypes. In addition, levels L4-L5 showed the highest IDH for all four groups followed by the L3-L4 and L5-S1 levels, and the value of L3-L4 is equivalent to that of L5-S1. All type groups showed moderate and positive correlations between the PI and IDH except the level of L1-L2 in type IV. The IDH may

  6. Assessment of mechanical properties of isolated bovine intervertebral discs from multi-parametric magnetic resonance imaging

    Science.gov (United States)

    2012-01-01

    Background The treatment planning of spine pathologies requires information on the rigidity and permeability of the intervertebral discs (IVDs). Magnetic resonance imaging (MRI) offers great potential as a sensitive and non-invasive technique for describing the mechanical properties of IVDs. However, the literature reported small correlation coefficients between mechanical properties and MRI parameters. Our hypothesis is that the compressive modulus and the permeability of the IVD can be predicted by a linear combination of MRI parameters. Methods Sixty IVDs were harvested from bovine tails, and randomly separated in four groups (in-situ, digested-6h, digested-18h, digested-24h). Multi-parametric MRI acquisitions were used to quantify the relaxation times T1 and T2, the magnetization transfer ratio MTR, the apparent diffusion coefficient ADC and the fractional anisotropy FA. Unconfined compression, confined compression and direct permeability measurements were performed to quantify the compressive moduli and the hydraulic permeabilities. Differences between groups were evaluated from a one way ANOVA. Multi linear regressions were performed between dependent mechanical properties and independent MRI parameters to verify our hypothesis. A principal component analysis was used to convert the set of possibly correlated variables into a set of linearly uncorrelated variables. Agglomerative Hierarchical Clustering was performed on the 3 principal components. Results Multilinear regressions showed that 45 to 80% of the Young’s modulus E, the aggregate modulus in absence of deformation HA0, the radial permeability kr and the axial permeability in absence of deformation k0 can be explained by the MRI parameters within both the nucleus pulposus and the annulus pulposus. The principal component analysis reduced our variables to two principal components with a cumulative variability of 52-65%, which increased to 70-82% when considering the third principal component. The

  7. Glycosaminoglycan chemical exchange saturation transfer of lumbar intervertebral discs in patients with spondyloarthritis.

    Science.gov (United States)

    Schleich, Christoph; Müller-Lutz, Anja; Matuschke, Felix; Sewerin, Philipp; Sengewein, Ruben; Schmitt, Benjamin; Ostendorf, Benedikt; Wittsack, Hans-Jörg; Stanke, Karolin; Antoch, Gerald; Miese, Falk

    2015-10-01

    To assess glycosaminoglycan (GAG) content of lumbar intervertebral discs (IVD) in patients with spondyloarthritis (SpA) using glycosaminoglycan chemical exchange saturation transfer (gagCEST). Ninety lumbar intervertebral discs of nine patients with SpA and nine age-matched healthy controls (eight patients with ankylosing spondylitis; one patient with spondylitis related to inflammatory bowel disease; mean age: 44.1 ± 14.0 years; range: 27-72 years) were examined with a 3T magnetic resonance imaging (MRI) scanner in this prospective study. The MRI protocol included standard morphological, sagittal T2 -weighted (T2 w) images to assess Pfirrmann score of the five lumbar IVDs (L1 to S1) and biochemical imaging with gagCEST to calculate a region of interest analysis of nucleus pulposus (NP) and annulus fibrosus (AF). Prior to statistical testing of gagCEST effects (MTRasym values in percent) in patients and controls, IVDs were classified according to the Pfirrmann score. Significantly lower gagCEST values of NP and AF were found in SpA patients compared with healthy volunteers (NP: 1.41% ± 0.41%, P = 0.001; 95% confidence interval, CI [0.600%-2.226%]; AF: 1.19% ± 0.32%, P < 0.001; CI [0.560%-1.822%]) by comparing the differences of the means. Pooled nondegenerative IVDs (Pfirrmann 1 and 2) had significantly lower gagCEST effects in patients suffering from SpA compared with healthy controls in NP (P < 0.001; CI [1.176%-2.337%]) and AF (P < 0.001; CI [0.858%-1.779%]). No significant difference of MTRasym values was found in degenerative IVDs between patients and controls in NP (P = 0.204; CI [-0.504%-2.170%]). GagCEST analysis of morphologically nondegenerative IVDs (Pfirrmann score 1 and 2) in T2 w images demonstrated significantly lower GAG values in patients with spondyloarthritis in NP and AF, possibly representing a depletion of GAG in spondyloarthritis in the absence of morphologic degeneration. © 2015 Wiley Periodicals, Inc.

  8. Low rate loading-induced convection enhances net transport into the intervertebral disc in vivo.

    Science.gov (United States)

    Gullbrand, Sarah E; Peterson, Joshua; Mastropolo, Rosemarie; Roberts, Timothy T; Lawrence, James P; Glennon, Joseph C; DiRisio, Darryl J; Ledet, Eric H

    2015-05-01

    The intervertebral disc primarily relies on trans-endplate diffusion for the uptake of nutrients and the clearance of byproducts. In degenerative discs, diffusion is often diminished by endplate sclerosis and reduced proteoglycan content. Mechanical loading-induced convection has the potential to augment diffusion and enhance net transport into the disc. The ability of convection to augment disc transport is controversial and has not been demonstrated in vivo. To determine if loading-induced convection can enhance small molecule transport into the intervertebral disc in vivo. Net transport was quantified via postcontrast enhanced magnetic resonance imaging (MRI) into the discs of the New Zealand white rabbit lumbar spine subjected to in vivo cyclic low rate loading. Animals were administered the MRI contrast agent gadodiamide intravenously and subjected to in vivo low rate loading (0.5 Hz, 200 N) via a custom external loading apparatus for either 2.5, 5, 10, 15, or 20 minutes. Animals were then euthanized and the lumbar spines imaged using postcontrast enhanced MRI. The T1 constants in the nucleus, annulus, and cartilage endplates were quantified as a measure of gadodiamide transport into the loaded discs compared with the adjacent unloaded discs. Microcomputed tomography was used to quantify subchondral bone density. Low rate loading caused the rapid uptake and clearance of gadodiamide in the nucleus compared with unloaded discs, which exhibited a slower rate of uptake. Relative to unloaded discs, low rate loading caused a maximum increase in transport into the nucleus of 16.8% after 5 minutes of loading. Low rate loading increased the concentration of gadodiamide in the cartilage endplates at each time point compared with unloaded levels. Results from this study indicate that forced convection accelerated small molecule uptake and clearance in the disc induced by low rate mechanical loading. Low rate loading may, therefore, be therapeutic to the disc as it

  9. Reducing subsidence risk by using rapid manufactured patient-specific intervertebral disc implants.

    Science.gov (United States)

    de Beer, Neal; Scheffer, Cornie

    2012-11-01

    Intervertebral disc implant size, shape, and position during total disc replacement have been shown to affect the risk of implant subsidence or vertebral fracture. Rapid manufacturing has been successfully applied to produce patient-specific implants for craniomaxillofacial, dental, hip, and knee requirements, but very little has been published on its application for spinal implants. This research was undertaken to investigate the improved load distribution and stiffness that can be achieved when using implants with matching bone interface geometry as opposed to implants with flat end plate geometries. The study design comprises a biomechanical investigation and comparison of compressive loads applied to cadaveric vertebrae when using two different end plate designs. Four spines from male cadavers (ages 45-65 years, average 52 years), which had a total of n=88 vertebrae (C3-L5), were considered during this study. Bone mineral density scans on each spine revealed only one to be eligible for this study. Twenty remaining vertebrae (C3-L3) were potted and subjected to nondestructive compression tests followed by destructive compression tests. Custom-made nonfunctional implants were designed for this experiment. Ten implants were designed with matching end plate-to-bone interface geometry, whereas the other 10 were designed with flat end plates. Testing did not incorporate the use of a keel in either design type. I-Scan pressure sensors (Tekscan, Inc., MA, USA) were used during the nondestructive tests to assess the load distribution and percentage surface contact. Average percent contact area measured during nondestructive tests was 45.27% and 10.49% for conformal and flat implants, respectively-a difference that is statistically significant (pbone end plate. Subsidence depends in part on the stiffness of the implant-bone construct, and with a 137% increase in stiffness, the results of this study show that there are indeed significant potential benefits that can be

  10. FUNCTIONAL OUTCOME IN PATIENTS WHO UNDERWENT LUMBAR MICRODISCECTOMY FOR INTERVERTEBRAL DISC PROLAPSE (IVDP

    Directory of Open Access Journals (Sweden)

    Sudheer Urampath

    2016-11-01

    Full Text Available BACKGROUND Intervertebral Disc Prolapse (IVDP is a very common cause for low backache in younger population. When conservative treatment fails or when patient develops complications like neurological deficit, then the treatment is surgical discectomy. Open laminectomy and microdiscectomy are the modes of surgical interventions for such patients. There is a lot of morbidity for open laminectomy when compared to microdiscectomy to assess the functional outcome of patients underwent lumbar microdiscectomy. METHODS A prospective study was done among 30 patients with Intervertebral Disc Prolapse (IVDP who did not respond to conservative treatment were undergone the surgical procedure microdiscectomy. The patients were re-evaluated for pre and postoperative neurological deficit and postoperative pain relief at 1 week, 6 weeks, 6 months, 12 months and 24 months after surgery. RESULTS Out of 30 patients in 15 (50% patients, microdiscectomy was done in hip flexion and in the remaining half (15 patients it was done without hip flexion. There were 18 men and 12 women with a mean age of 39.4. All patients 30 (100% is presented with preoperative neurological impairment had a positive Lasegue sign, 20 (66.67% had motor deficits and 18 (60% had sensory deficits. In this study group, the vertebral levels mainly affected were L4-L5 in 18 (60% patients and L5-S1 in 12 (40% patients. After microdiscectomy, motor deficit was reduced from 66.67% to 20% out of 30 patients by the end of one year. Similarly, a reduction in sensory deficit was also seen from 60% to 20%. Pain relief was also found to be excellent in 86.6% patients at the end of 24 months. CONCLUSION Early postoperative mobilisation and earlier pain relief are the most important advantages of this novel technique. Lesser blood loss, low surgical time, least destabilisation of spine are other merits of this procedure and can be recommended as the gold standard surgical method for patients with IVDP who

  11. Total disc replacement using a tissue-engineered intervertebral disc in vivo: new animal model and initial results.

    Science.gov (United States)

    Gebhard, Harry; Bowles, Robby; Dyke, Jonathan; Saleh, Tatianna; Doty, Stephen; Bonassar, Lawrence; Härtl, Roger

    2010-08-01

     Basic science Introduction:  Chronic back pain due to degenerative disc disease (DDD) is among the most important medical conditions causing morbidity and significant health care costs. Surgical treatment options include disc replacement or fusion surgery, but are associated with significant short- and long-term risks.1 Biological tissue-engineering of human intervertebral discs (IVD) could offer an important alternative.2 Recent in vitro data from our group have shown successful engineering and growth of ovine intervertebral disc composites with circumferentially aligned collagen fibrils in the annulus fibrosus (AF) (Figure 1).3 Figure 1 Tissue-engineered composite disc a Experimental steps to generate composite tissue-engineered IVDs3b Example of different AF formulations on collagen alignment in the AF. Second harmonic generation and two-photon excited fluorescence images of seeded collagen gels (for AF) of 1 and 2.5 mg/ml over time. At seeding, cells and collagen were homogenously distributed in the gels. Over time, AF cells elongated and collagen aligned parallel to cells. Less contraction and less alignment is noted after 3 days in the 2.5 mg/mL gel. c Imaging-based creation of a virtual disc model that will serve as template for the engineered disc. Total disc dimensions (AF and NP) were retrieved from micro-computer tomography (CT) (left images), and nucleus pulposus (NP) dimensions alone were retrieved from T2-weighted MRI images (right images). Merging of MRI and micro-CT models revealed a composite disc model (middle image)-Software: Microview, GE Healthcare Inc., Princeton, NJ; and slicOmatic v4.3, TomoVision, Montreal, Canada. d Flow chart describing the process for generating multi-lamellar tissue engineered IVDs. IVDs are produced by allowing cell-seeded collagen layers to contract around a cell-seeded alginate core (NP) over time Objective:  The next step is to investigate if biological disc implants survive, integrate, and restore function

  12. Disk-to-Disk network transfers at 100 Gb/s

    Science.gov (United States)

    Barczyk, Artur; Gable, Ian; Hay, Marilyn; Leavett-Brown, Colin; Legrand, Iosif; Lewall, Kim; McKee, Shawn; McWilliam, Donald; Mughal, Azher; Newman, Harvey; Rozsa, Sandor; Savard, Yvan; Sobie, Randall J.; Tam, Thomas; Voicu, Ramiro

    2012-12-01

    A 100 Gbps network was established between the California Institute of Technology conference booth at the Super Computing 2011 conference in Seattle, Washington and the computing center at the University of Victoria in Canada. A circuit was established over the BCNET, CANARIE and Super Computing (SCInet) networks using dedicated equipment. The small set of servers at the endpoints used a combination of 10GE and 40GE technologies, and SSD drives for data storage. The configuration of the network and the server configuration are discussed. We will show that the system was able to achieve disk-to-disk transfer rates of 60 Gbps and memory-to-memory rates in excess of 180 Gbps across the WAN. We will discuss the transfer tools, disk configurations, and monitoring tools used in the demonstration.

  13. Intervertebral disc and stem cells cocultured in biomimetic extracellular matrix stimulated by cyclic compression in perfusion bioreactor.

    Science.gov (United States)

    Tsai, Tsung-Lin; Nelson, Brenton C; Anderson, Paul A; Zdeblick, Thomas A; Li, Wan-Ju

    2014-09-01

    Intervertebral disc (IVD) degeneration often causes back pain. Current treatments for disc degeneration, including both surgical and nonsurgical approaches, tend to compromise the disc movement and cannot fully restore functions of the IVD. Instead, cell-based IVD tissue engineering seems promising as an ultimate therapy for IVD degeneration. To tissue-engineer an IVD ex vivo as a biological substitute to replace degenerative IVD. An extracellular matrix (ECM) structure-mimetic scaffold, cocultured human IVD cells and human mesenchymal stem cells (hMSCs), and mechanical stimulation were used to biofabricate a tissue-engineered IVD. An optimal ratio of human annulus fibrosus (hAF) cells to hMSCs for AF generation within aligned nanofibers, and that of human nucleus pulposus (hNP) cells to hMSCs for NP generation within hydrogels were first determined after comparing different coculture ratios of hAF or hNP cells to hMSCs. Nanofibrous strips seeded with cocultured hAF cells/hMSCs were constructed into multilayer concentric rings, enclosing an inner core of hydrogel seeded with hNP cells/hMSCs. A piece of nonwoven nanofibrous mat seeded with hMSC-derived osteoblasts was assembled on the top of the cellular nanofiber/hydrogel assembly, as an interface layer between the cartilagenous end plate and vertebral body. The final assembled construct was then maintained in an osteochondral cocktail medium and stimulated with compressive loading to further enhance the hAF and hNP cells differentiation and increase the IVD ECM production. Among all cocultured groups, hAF cells and hMSCs in the ratio of 2:1 cultured in nanofibers showed the closest mRNA expression levels of AF-related markers to positive control hAF cells, whereas hNP cells and hMSCs in the ratio of 1:2 cultured in hydrogels showed the closest expression levels of NP-related markers to positive control hNP cells. The effects of compressive loading on chondrogenesis of hAF or hNP cell and hMSC coculture were

  14. An Optimal Strategy for Accurate Bulge-to-disk Decomposition of Disk Galaxies

    Science.gov (United States)

    Gao, Hua; Ho, Luis C.

    2017-08-01

    The development of two-dimensional (2D) bulge-to-disk decomposition techniques has shown their advantages over traditional one-dimensional (1D) techniques, especially for galaxies with non-axisymmetric features. However, the full potential of 2D techniques has yet to be fully exploited. Secondary morphological features in nearby disk galaxies, such as bars, lenses, rings, disk breaks, and spiral arms, are seldom accounted for in 2D image decompositions, even though some image-fitting codes, such as GALFIT, are capable of handling them. We present detailed, 2D multi-model and multi-component decomposition of high-quality R-band images of a representative sample of nearby disk galaxies selected from the Carnegie-Irvine Galaxy Survey, using the latest version of GALFIT. The sample consists of five barred and five unbarred galaxies, spanning Hubble types from S0 to Sc. Traditional 1D decomposition is also presented for comparison. In detailed case studies of the 10 galaxies, we successfully model the secondary morphological features. Through a comparison of best-fit parameters obtained from different input surface brightness models, we identify morphological features that significantly impact bulge measurements. We show that nuclear and inner lenses/rings and disk breaks must be properly taken into account to obtain accurate bulge parameters, whereas outer lenses/rings and spiral arms have a negligible effect. We provide an optimal strategy to measure bulge parameters of typical disk galaxies, as well as prescriptions to estimate realistic uncertainties of them, which will benefit subsequent decomposition of a larger galaxy sample.

  15. An Optimal Strategy for Accurate Bulge-to-disk Decomposition of Disk Galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Gao Hua [Department of Astronomy, School of Physics, Peking University, Beijing 100871 (China); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)

    2017-08-20

    The development of two-dimensional (2D) bulge-to-disk decomposition techniques has shown their advantages over traditional one-dimensional (1D) techniques, especially for galaxies with non-axisymmetric features. However, the full potential of 2D techniques has yet to be fully exploited. Secondary morphological features in nearby disk galaxies, such as bars, lenses, rings, disk breaks, and spiral arms, are seldom accounted for in 2D image decompositions, even though some image-fitting codes, such as GALFIT, are capable of handling them. We present detailed, 2D multi-model and multi-component decomposition of high-quality R -band images of a representative sample of nearby disk galaxies selected from the Carnegie-Irvine Galaxy Survey, using the latest version of GALFIT. The sample consists of five barred and five unbarred galaxies, spanning Hubble types from S0 to Sc. Traditional 1D decomposition is also presented for comparison. In detailed case studies of the 10 galaxies, we successfully model the secondary morphological features. Through a comparison of best-fit parameters obtained from different input surface brightness models, we identify morphological features that significantly impact bulge measurements. We show that nuclear and inner lenses/rings and disk breaks must be properly taken into account to obtain accurate bulge parameters, whereas outer lenses/rings and spiral arms have a negligible effect. We provide an optimal strategy to measure bulge parameters of typical disk galaxies, as well as prescriptions to estimate realistic uncertainties of them, which will benefit subsequent decomposition of a larger galaxy sample.

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