A multi-cell, multi-scale model of vertebrate segmentation and somite formation.

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Susan D Hester

2011-10-01

Full Text Available Somitogenesis, the formation of the body's primary segmental structure common to all vertebrate development, requires coordination between biological mechanisms at several scales. Explaining how these mechanisms interact across scales and how events are coordinated in space and time is necessary for a complete understanding of somitogenesis and its evolutionary flexibility. So far, mechanisms of somitogenesis have been studied independently. To test the consistency, integrability and combined explanatory power of current prevailing hypotheses, we built an integrated clock-and-wavefront model including submodels of the intracellular segmentation clock, intercellular segmentation-clock coupling via Delta/Notch signaling, an FGF8 determination front, delayed differentiation, clock-wavefront readout, and differential-cell-cell-adhesion-driven cell sorting. We identify inconsistencies between existing submodels and gaps in the current understanding of somitogenesis mechanisms, and propose novel submodels and extensions of existing submodels where necessary. For reasonable initial conditions, 2D simulations of our model robustly generate spatially and temporally regular somites, realistic dynamic morphologies and spontaneous emergence of anterior-traveling stripes of Lfng. We show that these traveling stripes are pseudo-waves rather than true propagating waves. Our model is flexible enough to generate interspecies-like variation in somite size in response to changes in the PSM growth rate and segmentation-clock period, and in the number and width of Lfng stripes in response to changes in the PSM growth rate, segmentation-clock period and PSM length.

Brothers with hypospadias, vertebral segmentation defects, and intellectual disability: new syndrome?

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Phadke, Shubha R; Ranganath, Prajnya; Boggula, Vijay Raju; Gupta, Divya; Phadke, Rajendra V; Sloman, Melissa; Turnpenny, Peter D

2012-12-01

We report on two brothers (born to nonconsanguineous parents) with short stature, hypospadias, scoliosis, vertebral segmentation defects of "spondylocostal dysostosis" type, and intellectual disability. Results of cytogenetic and molecular genetic tests performed, including routine karyotype, MLPA (multiplex ligation-dependent probe amplification) for common microdeletions and subtelomeric copy number variants, microarray-CGH analysis, and sequencing of four Notch signaling pathway genes (DLL3, MESP2, LFNG, and HES7), were all normal. We present a comparison of the condition in the two boys with known syndromes and suggest that they may represent a hitherto unreported syndrome, most likely following autosomal recessive inheritance, though X-linked inheritance is not excluded. Copyright © 2012 Wiley Periodicals, Inc.

Bilateral segmental regression of the carotid and vertebral arteries with rete compensation in a Western patient

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Mahadevan, J.; Batista, L.; Alvarez, H.; Lasjaunias, P. [Service de Neuroradiologie Diagnostique et Therapeutique, Hopital de Bicetre, 94275 Le Kremlin Bicetre, 94275, Le Kremlin Bicetre (France); Bravo-Castro, E. [Instituto De Neurocirugia Asenjo, c/Jose Manuel Infante, Santiago (Chile)

2004-06-01

We report a case of symptomatic symmetrical, bilateral absence of the cavernous internal carotid (ICA) and transdural vertebral artery (VA) segments with formation of a rete mirabile. There have been similar reports in Asian patients; ours is the first in the Western population. A 29- year-old woman presented with recurrent temporary blindness and an episode of minor subarachnoid haemorrhage. Angiography demonstrated absence of the C5 and C6 segments of the ICA and the C1/2 segments of the VA bilaterally, with typical carotid rete mirabile formation to reconstitute the distal flow. Comparative anatomy and embryology show retia in several species and point to their secondary origin. The anomalies of the ICA cannot be called agenesis but rather absence since they are likely to result from perinatal disappearance of the artery rather its failure to develop. (orig.)

Midterm Follow-Up of Vertebral Geometry and Remodeling of the Vertebral Bidisk Unit (VDU) After Percutaneous Vertebroplasty of Osteoporotic Vertebral Fractures

International Nuclear Information System (INIS)

Pitton, Michael Bernhard; Koch, Ulrike; Drees, Philip; Dueber, Christoph

2009-01-01

The purpose of this study was to investigate geometrical stability and preservation of height gain of vertebral bodies after percutaneous vertebroplasty during 2 years' follow-up and to elucidate the geometric remodeling process of the vertebral bidisk unit (VDU) of the affected segment. Patients with osteoporotic vertebral compression fractures with pain resistant to analgetic drugs were treated with polymethylmethacrylate vertebroplasty. Mean ± standard error cement volume was 5.1 ± 2.0 ml. Vertebral geometry was documented by sagittal and coronal reformations from multidetector computed tomography data sets: anterior, posterior, and lateral vertebral heights, end plate angles, and compression index (CI = anterior/posterior height). Additionally, the VDU (vertebral bodies plus both adjacent disk spaces) was calculated from the multidetector computed tomography data sets: anterior, posterior, and both lateral aspects. Patients were assigned to two groups: moderate compression with CI of >0.75 (group 1) and severe compression with CI of o vs. -1.0 ± 2.7 o , P o , P < 0.01) and compression indices (+0.11 ± 0.15, P < 0.01). Thus, posterior height loss of vertebrae and adjacent intervertebral disk spaces contributed to a remodeling of the VDU, resulting in some compensation of the kyphotic malposition of the affected vertebral segment. Vertebroplasty improved vertebral geometry during midterm follow-up. In severe vertebral compression, significant height gain and improvement of end plate angles were achieved. The remodeling of the VDUs contributes to reduction of kyphosis and an overall improvement of the statics of the spine.

Volume of Lytic Vertebral Body Metastatic Disease Quantified Using Computed Tomography–Based Image Segmentation Predicts Fracture Risk After Spine Stereotactic Body Radiation Therapy

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Thibault, Isabelle [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Department of Radiation Oncology, Centre Hospitalier de L' Universite de Québec–Université Laval, Quebec, Quebec (Canada); Whyne, Cari M. [Orthopaedic Biomechanics Laboratory, Sunnybrook Research Institute, Department of Surgery, University of Toronto, Toronto, Ontario (Canada); Zhou, Stephanie; Campbell, Mikki [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Atenafu, Eshetu G. [Department of Biostatistics, University Health Network, University of Toronto, Toronto, Ontario (Canada); Myrehaug, Sten; Soliman, Hany; Lee, Young K. [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Ebrahimi, Hamid [Orthopaedic Biomechanics Laboratory, Sunnybrook Research Institute, Department of Surgery, University of Toronto, Toronto, Ontario (Canada); Yee, Albert J.M. [Division of Orthopaedic Surgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Sahgal, Arjun, E-mail: arjun.sahgal@sunnybrook.ca [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)

2017-01-01

Purpose: To determine a threshold of vertebral body (VB) osteolytic or osteoblastic tumor involvement that would predict vertebral compression fracture (VCF) risk after stereotactic body radiation therapy (SBRT), using volumetric image-segmentation software. Methods and Materials: A computational semiautomated skeletal metastasis segmentation process refined in our laboratory was applied to the pretreatment planning CT scan of 100 vertebral segments in 55 patients treated with spine SBRT. Each VB was segmented and the percentage of lytic and/or blastic disease by volume determined. Results: The cumulative incidence of VCF at 3 and 12 months was 14.1% and 17.3%, respectively. The median follow-up was 7.3 months (range, 0.6-67.6 months). In all, 56% of segments were determined lytic, 23% blastic, and 21% mixed, according to clinical radiologic determination. Within these 3 clinical cohorts, the segmentation-determined mean percentages of lytic and blastic tumor were 8.9% and 6.0%, 0.2% and 26.9%, and 3.4% and 15.8% by volume, respectively. On the basis of the entire cohort (n=100), a significant association was observed for the osteolytic percentage measures and the occurrence of VCF (P<.001) but not for the osteoblastic measures. The most significant lytic disease threshold was observed at ≥11.6% (odds ratio 37.4, 95% confidence interval 9.4-148.9). On multivariable analysis, ≥11.6% lytic disease (P<.001), baseline VCF (P<.001), and SBRT with ≥20 Gy per fraction (P=.014) were predictive. Conclusions: Pretreatment lytic VB disease volumetric measures, independent of the blastic component, predict for SBRT-induced VCF. Larger-scale trials evaluating our software are planned to validate the results.

Investigation of biomechanical behavior of lumbar vertebral segments with dynamic stabilization device using finite element approach

Science.gov (United States)

Deoghare, Ashish B.; Kashyap, Siddharth; Padole, Pramod M.

2013-03-01

Degenerative disc disease is a major source of lower back pain and significantly alters the biomechanics of the lumbar spine. Dynamic stabilization device is a remedial technique which uses flexible materials to stabilize the affected lumbar region while preserving the natural anatomy of the spine. The main objective of this research work is to investigate the stiffness variation of dynamic stabilization device under various loading conditions under compression, axial rotation and flexion. Three dimensional model of the two segment lumbar spine is developed using computed tomography (CT) scan images. The lumbar structure developed is analyzed in ANSYS workbench. Two types of dynamic stabilization are considered: one with stabilizing device as pedicle instrumentation and second with stabilization device inserted around the inter-vertebral disc. Analysis suggests that proper positioning of the dynamic stabilization device is of paramount significance prior to the surgery. Inserting the device in the posterior region indicates the adverse effects as it shows increase in the deformation of the inter-vertebral disc. Analysis executed by positioning stabilizing device around the inter-vertebral disc yields better result for various stiffness values under compression and other loadings. [Figure not available: see fulltext.

Automatic segmentation of vertebrae from radiographs

DEFF Research Database (Denmark)

Mysling, Peter; Petersen, Peter Kersten; Nielsen, Mads

2011-01-01

Segmentation of vertebral contours is an essential task in the design of automatic tools for vertebral fracture assessment. In this paper, we propose a novel segmentation technique which does not require operator interaction. The proposed technique solves the segmentation problem in a hierarchical...... is constrained by a conditional shape model, based on the variability of the coarse spine location estimates. The technique is evaluated on a data set of manually annotated lumbar radiographs. The results compare favorably to the previous work in automatic vertebra segmentation, in terms of both segmentation...

STUDY OF VERTEBRAL MORPHOGENESIS OF COBIA LARVAE, (Rachycentron canadum BY DOUBLE STAINING METHODS

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Afifah Nasukha

2012-12-01

Full Text Available Vertebral development is one of the main indicators of organism growth. The aim of this study was to know the vertebral development of cobia Rachycentron canadum in larval stage (20 day post hatch. Vertebral assay was done with double staining methods. The result showed that cobia larvae from 0 dph up to 5 dph did not have cartilage. On 5 dph up to 10 dph had pre cartilage phase composed by calcium and on 10 dph up to 18 dph were cartilage phase and marked with blue color by alcian blue. Vertebral was formed perfectly as bones on 18 dph marked with red color by alizarin red. On 20 dph, cartilage had been fully transformed to bones, and the segment of vertebral was clearly formed. Measurement showed that length of cobia vertebrae was 20.20±3.90 mm, vertebrae segment was 0.91±0.11 mm and number of vertebral segments were between 25-26 segments.

Excess entropy scaling for the segmental and global dynamics of polyethylene melts.

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Voyiatzis, Evangelos; Müller-Plathe, Florian; Böhm, Michael C

2014-11-28

The range of validity of the Rosenfeld and Dzugutov excess entropy scaling laws is analyzed for unentangled linear polyethylene chains. We consider two segmental dynamical quantities, i.e. the bond and the torsional relaxation times, and two global ones, i.e. the chain diffusion coefficient and the viscosity. The excess entropy is approximated by either a series expansion of the entropy in terms of the pair correlation function or by an equation of state for polymers developed in the context of the self associating fluid theory. For the whole range of temperatures and chain lengths considered, the two estimates of the excess entropy are linearly correlated. The scaled bond and torsional relaxation times fall into a master curve irrespective of the chain length and the employed scaling scheme. Both quantities depend non-linearly on the excess entropy. For a fixed chain length, the reduced diffusion coefficient and viscosity scale linearly with the excess entropy. An empirical reduction to a chain length-independent master curve is accessible for both dynamic quantities. The Dzugutov scheme predicts an increased value of the scaled diffusion coefficient with increasing chain length which contrasts physical expectations. The origin of this trend can be traced back to the density dependence of the scaling factors. This finding has not been observed previously for Lennard-Jones chain systems (Macromolecules, 2013, 46, 8710-8723). Thus, it limits the applicability of the Dzugutov approach to polymers. In connection with diffusion coefficients and viscosities, the Rosenfeld scaling law appears to be of higher quality than the Dzugutov approach. An empirical excess entropy scaling is also proposed which leads to a chain length-independent correlation. It is expected to be valid for polymers in the Rouse regime.

Osmotic and Heat Stress Effects on Segmentation.

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Julian Weiss

Full Text Available During vertebrate embryonic development, early skin, muscle, and bone progenitor populations organize into segments known as somites. Defects in this conserved process of segmentation lead to skeletal and muscular deformities, such as congenital scoliosis, a curvature of the spine caused by vertebral defects. Environmental stresses such as hypoxia or heat shock produce segmentation defects, and significantly increase the penetrance and severity of vertebral defects in genetically susceptible individuals. Here we show that a brief exposure to a high osmolarity solution causes reproducible segmentation defects in developing zebrafish (Danio rerio embryos. Both osmotic shock and heat shock produce border defects in a dose-dependent manner, with an increase in both frequency and severity of defects. We also show that osmotic treatment has a delayed effect on somite development, similar to that observed in heat shocked embryos. Our results establish osmotic shock as an alternate experimental model for stress, affecting segmentation in a manner comparable to other known environmental stressors. The similar effects of these two distinct environmental stressors support a model in which a variety of cellular stresses act through a related response pathway that leads to disturbances in the segmentation process.

The evolutionary origin of the vertebrate body plan: the problem of head segmentation.

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Onai, Takayuki; Irie, Naoki; Kuratani, Shigeru

2014-01-01

The basic body plan of vertebrates, as typified by the complex head structure, evolved from the last common ancestor approximately 530 Mya. In this review, we present a brief overview of historical discussions to disentangle the various concepts and arguments regarding the evolutionary development of the vertebrate body plan. We then explain the historical transition of the arguments about the vertebrate body plan from merely epistemological comparative morphology to comparative embryology as a scientific treatment on this topic. Finally, we review the current progress of molecular evidence regarding the basic vertebrate body plan, focusing on the link between the basic vertebrate body plan and the evolutionarily conserved developmental stages (phylotypic stages).

Distal vertebral artery reconstruction when managing vertebrobasilar insufficiency

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D. M. Galaktionov

2017-11-01

Full Text Available This article presents a literature review devoted to the reconstruction of the distal vertebral artery and a clinical case of successful surgical treatment of a patient suffering from vertebrobasilar insufficiency caused by occlusion of the vertebral artery in a proximal segment. The external carotid artery-distal vertebral artery bypass was performed by using the radial artery.Received 27 February 2017. Revised 25 July 2017. Accepted 3 August 2017.Funding: The study did not have sponsorship.Conflict of interest: The authors declare no conflict of interest. 

Automatic detection of osteoporotic vertebral fractures in routine thoracic and abdominal MDCT

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Baum, Thomas; Dobritz, Martin; Rummeny, Ernst J.; Noel, Peter B. [Technische Universitaet Muenchen, Institut fuer Radiologie, Klinikum rechts der Isar, Muenchen (Germany); Bauer, Jan S. [Technische Universitaet Muenchen, Abteilung fuer Neuroradiologie, Klinikum rechts der Isar, Muenchen (Germany); Klinder, Tobias; Lorenz, Cristian [Philips Research Laboratories, Hamburg (Germany)

2014-04-15

To develop a prototype algorithm for automatic spine segmentation in MDCT images and use it to automatically detect osteoporotic vertebral fractures. Cross-sectional routine thoracic and abdominal MDCT images of 71 patients including 8 males and 9 females with 25 osteoporotic vertebral fractures and longitudinal MDCT images of 9 patients with 18 incidental fractures in the follow-up MDCT were retrospectively selected. The spine segmentation algorithm localised and identified the vertebrae T5-L5. Each vertebra was automatically segmented by using corresponding vertebra surface shape models that were adapted to the original images. Anterior, middle, and posterior height of each vertebra was automatically determined; the anterior-posterior ratio (APR) and middle-posterior ratio (MPR) were computed. As the gold standard, radiologists graded vertebral fractures from T5 to L5 according to the Genant classification in consensus. Using ROC analysis to differentiate vertebrae without versus with prevalent fracture, AUC values of 0.84 and 0.83 were obtained for APR and MPR, respectively (p < 0.001). Longitudinal changes in APR and MPR were significantly different between vertebrae without versus with incidental fracture (ΔAPR: -8.5 % ± 8.6 % versus -1.6 % ± 4.2 %, p = 0.002; ΔMPR: -11.4 % ± 7.7 % versus -1.2 % ± 1.6 %, p < 0.001). This prototype algorithm may support radiologists in reporting currently underdiagnosed osteoporotic vertebral fractures so that appropriate therapy can be initiated. circle This spine segmentation algorithm automatically localised, identified, and segmented the vertebrae in MDCT images. (orig.)

Clinical application of multislice spiral CT angiography in evaluation of anomalous vertebral artery

International Nuclear Information System (INIS)

Hua Rui; Liu Jun; Zhang Yu

2008-01-01

Objective: To evaluate the diagnostic value of 16-slice spiral computed tomography angiography (MSCTA) in evaluation of anomalous vertebral artery. Methods: MSCTA data from 32 patients with anomalous vertebral artery were retrospectively analyzed. Results: 22 cases had vertebral artery course variation (bended into the C 5 , C 4 or C 3 foramen transversarium), 7 cases had variation in the prevertebral segments of vertebral arteries, 15 patients had unilateral vertebral congenital stenosis, 1 case had double vertebral artery branch, 1 case had vertebral arterial fenestration, and 2 cases had vertebral artery in one side that did not converged upon basilar artery and unilateral vertebral artery formed basilar artery. Conclusion: MSCTA is a useful noninvasive imaging tool for the diagnosis of vertebral artery variations. (authors)

Built for speed: strain in the cartilaginous vertebral columns of sharks.

Science.gov (United States)

Porter, M E; Diaz, Candido; Sturm, Joshua J; Grotmol, Sindre; Summers, A P; Long, John H

2014-02-01

In most bony fishes vertebral column strain during locomotion is almost exclusively in the intervertebral joints, and when these joints move there is the potential to store and release strain energy. Since cartilaginous fishes have poorly mineralized vertebral centra, we tested whether the vertebral bodies undergo substantial strain and thus may be sites of energy storage during locomotion. We measured axial strains of the intervertebral joints and vertebrae in vivo and ex vivo to characterize the dynamic behavior of the vertebral column. We used sonomicrometry to directly measure in vivo and in situ strains of intervertebral joints and vertebrae of Squalus acanthias swimming in a flume. For ex vivo measurements, we used a materials testing system to dynamically bend segments of vertebral column at frequencies ranging from 0.25 to 1.00 Hz and a range of physiologically relevant curvatures, which were determined using a kinematic analysis. The vertebral centra of S. acanthias undergo strain during in vivo volitional movements as well as in situ passive movements. Moreover, when isolated segments of vertebral column were tested during mechanical bending, we measured the same magnitudes of strain. These data support our hypothesis that vertebral column strain in lateral bending is not limited to the intervertebral joints. In histological sections, we found that the vertebral column of S. acanthias has an intracentral canal that is open and covered with a velum layer. An open intracentral canal may indicate that the centra are acting as tunics around some sections of a hydrostat, effectively stiffening the vertebral column. These data suggest that the entire vertebral column of sharks, both joints and centra, is mechanically engaged as a dynamic spring during locomotion. Copyright © 2013 Elsevier GmbH. All rights reserved.

Segmental torso masses in adolescent idiopathic scoliosis.

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Keenan, Bethany E; Izatt, Maree T; Askin, Geoffrey N; Labrom, Robert D; Pettet, Graeme J; Pearcy, Mark J; Adam, Clayton J

2014-08-01

Adolescent idiopathic scoliosis is the most common type of spinal deformity whose aetiology remains unclear. Studies suggest that gravitational forces in the standing position play an important role in scoliosis progression, therefore anthropometric data is required to develop biomechanical models of the deformity. Few studies have analysed the trunk by vertebral level and none have performed investigations of the scoliotic trunk. The aim of this study was to determine the centroid, thickness, volume and estimated mass, for sections of the scoliotic trunk. Existing low-dose CT scans were used to estimate vertebral level-by-level torso masses for 20 female adolescent idiopathic scoliosis patients. ImageJ processing software was used to analyse the CT images and enable estimation of the segmental torso mass corresponding to each vertebral level. The patients' mean age was 15.0 (SD 2.7) years with mean major Cobb angle of 52 (SD 5.9)° and mean patient weight of 58.2 (SD 11.6) kg. The magnitude of torso segment mass corresponding to each vertebral level increased by 150% from 0.6kg at T1 to 1.5kg at L5. Similarly, segmental thickness from T1-L5 increased inferiorly from a mean 18.5 (SD 2.2) mm at T1 to 32.8 (SD 3.4) mm at L5. The mean total trunk mass, as a percentage of total body mass, was 27.8 (SD 0.5) % which was close to values reported in previous literature. This study provides new anthropometric reference data on segmental (vertebral level-by-level) torso mass in adolescent idiopathic scoliosis patients, useful for biomechanical models of scoliosis progression and treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Geometry of the vertebral bodies and the intervertebral discs in lumbar segments adjacent to spondylolysis and spondylolisthesis: pilot study.

Science.gov (United States)

Been, Ella; Li, Ling; Hunter, David J; Kalichman, Leonid

2011-07-01

The objective is to evaluate the geometric parameters of vertebral bodies and intervertebral discs in spinal segments adjacent to spondylolysis and spondylolisthesis. This pilot cross-sectional study was an ancillary project to the Framingham Heart Study. The presence of spondylolysis and spondylolisthesis as well as measurements of spinal geometry were identified on CT imaging of 188 individuals. Spinal geometry measurements included lordosis angle, wedging of each lumbar vertebra and intervertebral disc. Last measurements were used to calculate ΣB, the sum of the lumbar L1-L5 body wedge angles; and ΣD, the sum of the lumbar L1-L5 intervertebral disc angles. Using Wilcoxon-Mann-Whitney test we compared the geometric parameters between individuals with no pathology and ones with spondylolysis (with no listhesis) at L5 vertebra, ones with isthmic spondylolisthesis at L5-S1 level, and ones with degenerative spondylolisthesis at L5-S1 level. Spinal geometry in individuals with spondylolysis or listhesis at L5 shows three major patterns: In spondylolysis without listhesis, spinal morphology is similar to that of healthy individuals; In isthmic spondylolisthesis there is high lordosis angle, high L5 vertebral body wedging and very high L4-5 disc wedging; In degenerative spondylolisthesis, spinal morphology shows more lordotic wedging of the L5 vertebral body, and less lordotic wedging of intervertebral discs. In conclusion, there are unique geometrical features of the vertebrae and discs in spondylolysis or listhesis. These findings need to be reproduced in larger scale study.

USE OF CT FOR ANALYSIS OF THE VERTEBRAL FORAMEN IN THE HOSPITAL OF QUERÉTARO

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JESÚS CISNEROS LÁMBARRI

Full Text Available ABSTRACT Objective: To determine the morphology of the vertebral foramen and its distance to the midline. Methods: Twenty cervical CT scans from the radiographic record of 12 men and 8 women, 18 to 74 years old, of C1 to C6 segments were evaluated, measuring the foramen diameter and its distance to the midline. We look for anomalies of vertebral foramen morphology, using Philips Ingenuity CT equipment with Philips IntelliSpace Portal software. Results: The mean age was 47 years; the segment with the most anomalies was C1, with 10% (increase in foramen diameter, followed by C2 and C6, with 5% (vertebral foramen hypotrophy; the mean diameter of the C1 to C6 segment was 6.081 mm, and the median distance from the midline to the vertebral foramen of C2 to C6 was 13.215 mm. The largest diameter of the vertebral foramen was C2, with a mean of 6.67 mm and the smallest was C4, with a mean of 5.75 mm; the greatest distance from the midline to the vertebral foramen was C1, with a mean of 22.59 mm and the shortest was C4, with a mean of 12.13 mm. Conclusions: The mean diameter of the vertebral foramen and its distance to the midline was determined, setting a safety region for procedures. In our city, there is no study that determines the means of the vertebral foramina diameters, the distance from the midline and its anomalies. It is necessary to rely on CT scans and to make a preoperative plan to avoid complications associated with morphological alterations.

Risk of vertebral compression fractures in multiple myeloma patients

OpenAIRE

Anitha, D.; Thomas, Baum; Jan, Kirschke S.; Subburaj, Karupppasamy

2017-01-01

Abstract The purpose of this study was to develop and validate a finite element (FE) model to predict vertebral bone strength in vitro using multidetector computed tomography (MDCT) images in multiple myeloma (MM) patients, to serve as a complementing tool to assess fracture risk. In addition, it also aims to differentiate MM patients with and without vertebral compression fractures (VCFs) by performing FE analysis on vertebra segments (T1?L5) obtained from in vivo routine MDCT imaging scans....

ANOMALOUS PREVERTEBRAL COURSE OF THE LEFT VERTEBRAL ARTERY. Recorrido prevertebral anómalo de la arteria vertebral izquierda

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Prakash B Billakanti

2016-03-01

Full Text Available La arteria vertebral es una de las arterias que irriga el cerebro. El conocimiento de la anatomía normal y las variantes de la arteria vertebral adquiere importancia en la práctica clínica y la radiología vascular. El origen anómalo de la arteria vertebral del arco de la aorta o cualquiera de las arterias del cuello ha sido reportado por muchos autores. En este informe se presenta una variación del curso prevertebral de la arteria vertebral izquierda. La arteria vertebral tenía su origen habitual en la arteria subclavia con un largo curso prevertebral y entraba en el foramen transversarium de la vértebra CII. El origen y recorrido de la arteria vertebral en el lado derecho fue normal. Clínicamente es importante conocer el origen y curso del segmento prevertebral de la arteria vertebral y las posibles variaciones. El presente informe debería ser de interés para el médico vascular con respecto a las variaciones en el cuello y región torácica, y puede dar idea para dilucidar el mecanismo de desarrollo de la angiogénesis. Vertebral artery is one of the arteries supplying the brain. Knowledge of the normal and variant anatomy of the vertebral artery assumes importance in clinical practice and vascular radiology. Anomalous origins of the vertebral artery from the arch of the aorta or any one of the arteries of the neck have been reported by several authors. In this report a variation of the prevertebral course of the left vertebral artery is being presented. The Vertebral artery had usual origin from the subclavian artery and had a longer prevertebral course to enter the foramen transversarium of the CII vertebra. The origin and course of the vertebral artery on the right side was normal. It is clinically important to know the origin and course of the prevertebral segment of the vertebral artery and possible variations. The present report should be of interest for clinicians with regard to vascular variations in the neck and thoracic

Nonsurgical Corrective Union of Osteoporotic Vertebral Fracture with Once-Weekly Teriparatide

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Naohisa Miyakoshi

2015-01-01

Full Text Available Osteoporotic vertebral fractures usually heal with kyphotic deformities with subsidence of the vertebral body when treated conservatively. Corrective vertebral union using only antiosteoporotic pharmacotherapy without surgical intervention has not been reported previously. An 81-year-old female with osteoporosis presented with symptomatic fresh L1 vertebral fracture with intravertebral cleft. Segmental vertebral kyphosis angle (VKA at L1 was 20° at diagnosis. Once-weekly teriparatide administration, hospitalized rest, and application of a thoracolumbosacral orthosis alleviated symptoms within 2 months. Corrective union of the affected vertebra was obtained with these treatments. VKA at 2 months after injury was 8° (correction, 12° and was maintained as of the latest follow-up at 7 months. Teriparatide has potent bone-forming effects and has thus been expected to enhance fracture healing. Based on the clinical experience of this case, teriparatide may have the potential to allow correction of unstable vertebral fractures without surgical intervention.

Significance of angular mismatch between vertebral endplate and prosthetic endplate in lumbar total disc replacement.

Science.gov (United States)

Lee, Chong Suh; Chung, Sung Soo; Oh, Sung Kyun; You, Je Wook

2011-05-01

A retrospective study. To determine whether angular mismatch between the vertebral endplate and prosthetic endplate during lumbar total disc replacement (L-TDR) affects the radiological and clinical outcomes. A prosthesis anchored to the vertebral body by using a large central keel carries an inherent risk of angular mismatch between the vertebral endplate and prosthetic endplate at a segment with a greater degree of lordosis, such as L5-S1. Theoretically, this angular mismatch can cause several problems, such as segmental hyperlordosis, anterior positioning of the upper prosthesis, posterior prosthetic edge subsidence, decreased range of motion (ROM), and a poor clinical outcome. This study evaluated 64 prosthetic levels of 56 patients who were implanted with L-TDR between June 2002 and February 2006. There were 38 and 26 prosthetic levels at the L4-5 and L5-S1, respectively. The mean follow-up period was 25.6 (12 to 49) months. The angle of mismatch between the lower endplate of the upper vertebral body and the upper prosthetic plate, segmental flexion/extension ROM, segmental lordosis angle at extension, distance from the posterior wall of the vertebral body to the posterior prosthetic edge were measured by obtaining radiographs. Clinically, the Visual Analogue Scale and Oswestry Disability Index were also evaluated. The angular mismatches between the upper vertebra and prosthesis at L4-5 and L5-S1 were 1.6 degree and 5.6 degree, respectively (P body to the posterior edge of the prosthesis in L5-S1 were 6.8 degree (4 to 13), 12.8 degree (8 to 17), and 3.8 mm (1 to 6 mm) in patients with an angular mismatch of 0.05). Angular mismatch was more common in L5-S1 than in L4-5. L-TDR at the most lordotic level, L5-S1, and implantation of an upper prosthesis with a mismatched angle seem to be the causes of a reduced segmental ROM, increased segmental lordosis, and anterior malpositioning of the prosthesis. However, these changes do not affect the clinical outcomes of

Spontaneous dissecting aneurysm of the extracranial vertebral artery (20 cases)

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Chiras, J; Marciano, S; Vega Molina, J; Touboul, J; Poirier, B; Bories, J

1985-07-01

Spontaneous dissecting aneurysm of the vertebral artery is an infrequent cause of vertebro basilar ischemic strokes. Previously reported cases concern essentially occlusion of the basilar artery. Only 14 cases of spontaneous dissecting aneurysm concern the extracranial vertebral artery among these eight were angiographically documented. In this study based upon 15 patients (20 dissecting aneurysms), the authors discuss etiological factors, such as hypertension or fibromuscular dysplasia: on clinical findings they insist upon the diagnostic value of preliminary symptoms, cervical pain or posterior headaches; the most frequent angiographic appearance was a long and irregular stenosis of one or two segments of the vertebral artery. The prognosis of these aneurysms most often appears favourable in this group.

Spine Patterning Is Guided by Segmentation of the Notochord Sheath

NARCIS (Netherlands)

Wopat, Susan; Bagwell, Jennifer; Sumigray, Kaelyn D.; Dickson, Amy L.; Huitema, Leonie F.A.; Poss, Kenneth D.; Schulte-Merker, Stefan; Bagnat, Michel

2018-01-01

The spine is a segmented axial structure made of alternating vertebral bodies (centra) and intervertebral discs (IVDs) assembled around the notochord. Here, we show that, prior to centra formation, the outer epithelial cell layer of the zebrafish notochord, the sheath, segments into alternating

Vertebral growth modulation by hemicircumferential electrocoagulation: an experimental study in pigs.

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Caballero, Alberto; Barrios, Carlos; Burgos, Jesús; Hevia, Eduardo; Correa, Carlos

2011-08-01

This experimental study in pigs was aimed at evaluating spinal growth disorders after partial arrest of the vertebral epiphyseal plates (EP) and neurocentral cartilages (NCC). Unilateral and multisegmental single or combined lesions of the physeal structures were performed by electrocoagulation throughout a video-assisted thoracoscopical approach. Thirty 4-week-old domestic pigs (mean weight 16 kg) were included in the experiments. The superior and inferior epiphyseal plates of T5 to T9 vertebra were damaged in ten animals by hemicircumferential electrocoagulation (group I). In other ten pigs (group II), right NCC at the same T5-T9 levels were damaged. Ten other animals underwent combined lesions of the ipsilateral hemiepiphyseal plates and NCC at the T5-T9 levels. A total of 26 animals could be evaluated after 12 weeks of follow-up using conventional X-rays, CT scans and histology. The pigs with hemicircumferential EP damage developed very slight concave non-structured scoliotic deformities without vertebral rotation.(mean 12° Cobb; range10-16°). Some of the damaged vertebra showed a marked wedgening with unilateral development alteration of the vertebral body, including the adjacent discs The animals with damage of the NCC developed mild scoliotic curves (mean 19° Cobb; range 16-24°) with convexity opposite to the damaged side and loss of physiological kyphosis. The injured segments showed an asymmetric growth with hypoplasia of the pedicle and costovertebral joints at the damaged side. The pigs undergoing combined EP and NCC lesions developed minimal non-structured curves, ranging from 10 to 12° Cobb. In these animals there was a lack of growth of a vertebral hemibody and disc hypoplasia at the damaged segments. Both damage of the NCC and the EP affect the height of the vertebral body. No spinal stenosis was found in any case. In most cases, the adjacent superior and inferior vertebral EP to damaged segments had a compensatory growth that maintained the

MRI-based anatomical landmarks for the identification of thoracic vertebral levels

International Nuclear Information System (INIS)

Connor, S.E.J.; Shah, A.; Latifoltojar, H.; Lung, P.

2013-01-01

Aim: To identify soft-tissue and bony anatomical landmarks on dedicated thoracic spine magnetic resonance imaging (MRI), and to assess their detectability, reproducibility, and accuracy in predicting specific thoracic vertebral levels. Materials and methods: One hundred dedicated thoracic MRI studies were retrospectively analysed by two radiologists independently. Ten bone and soft-tissue landmarks were localized to the adjacent vertebral level. The true numerical thoracic vertebral level was subsequently determined and recorded by cross referencing with a sagittal cervico-thoracic “counting scan”. Results: Six landmarks were defined in ≥98% cases; however, there was a low interobserver percentage agreement for the defined vertebral levels (>70% for only one landmark). The most useful landmark for defining a specific vertebral level was the most superior rib (98% detection, 95% interobserver agreement, 98% at a single vertebral level, 0.07 SD). Eight landmarks localized to a specific thoracic segment in only 16–44% of cases, with a standard deviation of >0.5 vertebral levels and with a range which was greater than four vertebral levels. Conclusion: The C2 vertebra must be identified and cross referenced to the dedicated thoracic spine MRI, as other MRI-based anatomical landmarks are unreliable in determining the correct thoracic vertebral level

Vertebral deformity arising from an accelerated "creep" mechanism.

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Luo, Jin; Pollintine, Phillip; Gomm, Edward; Dolan, Patricia; Adams, Michael A

2012-09-01

Vertebral deformities often occur in patients who recall no trauma, and display no evident fracture on radiographs. We hypothesise that vertebral deformity can occur by a gradual creep mechanism which is accelerated following minor damage. "Creep" is continuous deformation under constant load. Forty-five thoracolumbar spine motion segments were tested from cadavers aged 42-92 years. Vertebral body areal BMD was measured using DXA. Specimens were compressed at 1 kN for 30 min, while creep in each vertebral body was measured using an optical MacReflex system. After 30 min recovery, each specimen was subjected to a controlled overload event which caused minor damage to one of its vertebrae. The creep test was then repeated. Vertebral body creep was measurable in specimens with BMD Creep was greater anteriorly than posteriorly (p creep by 800 % (anteriorly), 1,000 % (centrally) and 600 % (posteriorly). In 34 vertebrae with complete before-and-after data, anterior wedging occurring during the 1st creep test averaged 0.07° (STD 0.17°), and in the 2nd test (after minor damage) it averaged 0.79° (STD 1.03°). The increase was highly significant (P creep test was proportional to the severity of damage, as quantified by specimen height loss during the overload event (r (2) = 0.51, p creep to such an extent that it makes a substantial contribution to vertebral deformity.

Adaptive geodesic transform for segmentation of vertebrae on CT images

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Gaonkar, Bilwaj; Shu, Liao; Hermosillo, Gerardo; Zhan, Yiqiang

2014-03-01

Vertebral segmentation is a critical first step in any quantitative evaluation of vertebral pathology using CT images. This is especially challenging because bone marrow tissue has the same intensity profile as the muscle surrounding the bone. Thus simple methods such as thresholding or adaptive k-means fail to accurately segment vertebrae. While several other algorithms such as level sets may be used for segmentation any algorithm that is clinically deployable has to work in under a few seconds. To address these dual challenges we present here, a new algorithm based on the geodesic distance transform that is capable of segmenting the spinal vertebrae in under one second. To achieve this we extend the theory of the geodesic distance transforms proposed in1 to incorporate high level anatomical knowledge through adaptive weighting of image gradients. Such knowledge may be provided by the user directly or may be automatically generated by another algorithm. We incorporate information 'learnt' using a previously published machine learning algorithm2 to segment the L1 to L5 vertebrae. While we present a particular application here, the adaptive geodesic transform is a generic concept which can be applied to segmentation of other organs as well.

Development of the Synarcual in the Elephant Sharks (Holocephali; Chondrichthyes: Implications for Vertebral Formation and Fusion.

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Zerina Johanson

Full Text Available The synarcual is a structure incorporating multiple elements of two or more anterior vertebrae of the axial skeleton, forming immediately posterior to the cranium. It has been convergently acquired in the fossil group 'Placodermi', in Chondrichthyes (Holocephali, Batoidea, within the teleost group Syngnathiformes, and to varying degrees in a range of mammalian taxa. In addition, cervical vertebral fusion presents as an abnormal pathology in a variety of human disorders. Vertebrae develop from axially arranged somites, so that fusion could result from a failure of somite segmentation early in development, or from later heterotopic development of intervertebral bone or cartilage. Examination of early developmental stages indicates that in the Batoidea and the 'Placodermi', individual vertebrae developed normally and only later become incorporated into the synarcual, implying regular somite segmentation and vertebral development. Here we show that in the holocephalan Callorhinchus milii, uniform and regular vertebral segmentation also occurs, with anterior individual vertebra developing separately with subsequent fusion into a synarcual. Vertebral elements forming directly behind the synarcual continue to be incorporated into the synarcual through growth. This appears to be a common pattern through the Vertebrata. Research into human disorders, presenting as cervical fusion at birth, focuses on gene misexpression studies in humans and other mammals such as the mouse. However, in chondrichthyans, vertebral fusion represents the normal morphology, moreover, taxa such Leucoraja (Batoidea and Callorhinchus (Holocephali are increasingly used as laboratory animals, and the Callorhinchus genome has been sequenced and is available for study. Our observations on synarcual development in three major groups of early jawed vertebrates indicate that fusion involves heterotopic cartilage and perichondral bone/mineralised cartilage developing outside the regular

The sea lamprey meiotic map improves resolution of ancient vertebrate genome duplications.

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Smith, Jeramiah J; Keinath, Melissa C

2015-08-01

It is generally accepted that many genes present in vertebrate genomes owe their origin to two whole-genome duplications that occurred deep in the ancestry of the vertebrate lineage. However, details regarding the timing and outcome of these duplications are not well resolved. We present high-density meiotic and comparative genomic maps for the sea lamprey (Petromyzon marinus), a representative of an ancient lineage that diverged from all other vertebrates ∼550 million years ago. Linkage analyses yielded a total of 95 linkage groups, similar to the estimated number of germline chromosomes (1n ∼ 99), spanning a total of 5570.25 cM. Comparative mapping data yield strong support for the hypothesis that a single whole-genome duplication occurred in the basal vertebrate lineage, but do not strongly support a hypothetical second event. Rather, these comparative maps reveal several evolutionarily independent segmental duplications occurring over the last 600+ million years of chordate evolution. This refined history of vertebrate genome duplication should permit more precise investigations of vertebrate evolution. © 2015 Smith and Keinath; Published by Cold Spring Harbor Laboratory Press.

Statistics-based segmentation using a continuous-scale naive Bayes approach

DEFF Research Database (Denmark)

Laursen, Morten Stigaard; Midtiby, Henrik Skov; Kruger, Norbert

2014-01-01

Segmentation is a popular preprocessing stage in the field of machine vision. In agricultural applications it can be used to distinguish between living plant material and soil in images. The normalized difference vegetation index (NDVI) and excess green (ExG) color features are often used...... segmentation over the normalized vegetation difference index and excess green. The inputs to this color feature are the R, G, B, and near-infrared color wells, their chromaticities, and NDVI, ExG, and excess red. We apply the developed technique to a dataset consisting of 20 manually segmented images captured...

Characterizing the location of spinal and vertebral levels in the human cervical spinal cord.

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Cadotte, D W; Cadotte, A; Cohen-Adad, J; Fleet, D; Livne, M; Wilson, J R; Mikulis, D; Nugaeva, N; Fehlings, M G

2015-04-01

Advanced MR imaging techniques are critical to understanding the pathophysiology of conditions involving the spinal cord. We provide a novel, quantitative solution to map vertebral and spinal cord levels accounting for anatomic variability within the human spinal cord. For the first time, we report a population distribution of the segmental anatomy of the cervical spinal cord that has direct implications for the interpretation of advanced imaging studies most often conducted across groups of subjects. Twenty healthy volunteers underwent a T2-weighted, 3T MRI of the cervical spinal cord. Two experts marked the C3-C8 cervical nerve rootlets, C3-C7 vertebral bodies, and pontomedullary junction. A semiautomated algorithm was used to locate the centerline of the spinal cord and measure rostral-caudal distances from a fixed point in the brain stem, the pontomedullary junction, to each of the spinal rootlets and vertebral bodies. Distances to each location were compared across subjects. Six volunteers had 2 additional scans in neck flexion and extension to measure the effects of patient positioning in the scanner. We demonstrated that substantial variation exists in the rostral-caudal position of spinal cord segments among individuals and that prior methods of predicting spinal segments are imprecise. We also show that neck flexion or extension has little effect on the relative location of vertebral-versus-spinal levels. Accounting for spinal level variation is lacking in existing imaging studies. Future studies should account for this variation for accurate interpretation of the neuroanatomic origin of acquired MR signals. © 2015 by American Journal of Neuroradiology.

Anterior Overgrowth in Primary Curves, Compensatory Curves and Junctional Segments in Adolescent Idiopathic Scoliosis.

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Schlösser, Tom P C; van Stralen, Marijn; Chu, Winnie C W; Lam, Tsz-Ping; Ng, Bobby K W; Vincken, Koen L; Cheng, Jack C Y; Castelein, René M

2016-01-01

Although much attention has been given to the global three-dimensional aspect of adolescent idiopathic scoliosis (AIS), the accurate three-dimensional morphology of the primary and compensatory curves, as well as the intervening junctional segments, in the scoliotic spine has not been described before. A unique series of 77 AIS patients with high-resolution CT scans of the spine, acquired for surgical planning purposes, were included and compared to 22 healthy controls. Non-idiopathic curves were excluded. Endplate segmentation and local longitudinal axis in endplate plane enabled semi-automatic geometric analysis of the complete three-dimensional morphology of the spine, taking inter-vertebral rotation, intra-vertebral torsion and coronal and sagittal tilt into account. Intraclass correlation coefficients for interobserver reliability were 0.98-1.00. Coronal deviation, axial rotation and the exact length discrepancies in the reconstructed sagittal plane, as defined per vertebra and disc, were analyzed for each primary and compensatory curve as well as for the junctional segments in-between. The anterior-posterior difference of spinal length, based on "true" anterior and posterior points on endplates, was +3.8% for thoracic and +9.4% for (thoraco)lumbar curves, while the junctional segments were almost straight. This differed significantly from control group thoracic kyphosis (-4.1%; P<0.001) and lumbar lordosis (+7.8%; P<0.001). For all primary as well as compensatory curves, we observed linear correlations between the coronal Cobb angle, axial rotation and the anterior-posterior length difference (r≥0.729 for thoracic curves; r≥0.485 for (thoraco)lumbar curves). Excess anterior length of the spine in AIS has been described as a generalized growth disturbance, causing relative anterior spinal overgrowth. This study is the first to demonstrate that this anterior overgrowth is not a generalized phenomenon. It is confined to the primary as well as the

Automatic control: the vertebral column of dogfish sharks behaves as a continuously variable transmission with smoothly shifting functions.

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Porter, Marianne E; Ewoldt, Randy H; Long, John H

2016-09-15

During swimming in dogfish sharks, Squalus acanthias, both the intervertebral joints and the vertebral centra undergo significant strain. To investigate this system, unique among vertebrates, we cyclically bent isolated segments of 10 vertebrae and nine joints. For the first time in the biomechanics of fish vertebral columns, we simultaneously characterized non-linear elasticity and viscosity throughout the bending oscillation, extending recently proposed techniques for large-amplitude oscillatory shear (LAOS) characterization to large-amplitude oscillatory bending (LAOB). The vertebral column segments behave as non-linear viscoelastic springs. Elastic properties dominate for all frequencies and curvatures tested, increasing as either variable increases. Non-linearities within a bending cycle are most in evidence at the highest frequency, 2.0 Hz, and curvature, 5 m -1 Viscous bending properties are greatest at low frequencies and high curvatures, with non-linear effects occurring at all frequencies and curvatures. The range of mechanical behaviors includes that of springs and brakes, with smooth transitions between them that allow for continuously variable power transmission by the vertebral column to assist in the mechanics of undulatory propulsion. © 2016. Published by The Company of Biologists Ltd.

Variation in vertebral number and its morphological implication in Galaxias platei.

Science.gov (United States)

Barriga, J P; Milano, D; Cussac, V E

2013-11-01

Variation in the vertebral number of the puyen grande Galaxias platei was examined for specimens from 22 localities that span the entire distribution range of the species (from 40° to 55° S). The mean vertebral number (NMW ) increases towards high latitudes, i.e. Jordan's rule is applicable to this species. Owing to the wide geographic variation of the species, not only in latitude but also in altitude, the most explicative variable for NMW was mean winter air temperature, showing negative dependence. Morphological data suggest that the increment in vertebral number lies in the pre-pelvic region of the trunk and in the caudal region, but not in the segment between pelvic-fin insertion and the origin of the anal fin. As these alterations in body shape have important consequences for hydrodynamics and swimming performance, vertebral number variation in G. platei also holds implications for both individual and population fitness. © 2013 The Fisheries Society of the British Isles.

Whole vertebral bone segmentation method with a statistical intensity-shape model based approach

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Hanaoka, Shouhei; Fritscher, Karl; Schuler, Benedikt; Masutani, Yoshitaka; Hayashi, Naoto; Ohtomo, Kuni; Schubert, Rainer

2011-03-01

An automatic segmentation algorithm for the vertebrae in human body CT images is presented. Especially we focused on constructing and utilizing 4 different statistical intensity-shape combined models for the cervical, upper / lower thoracic and lumbar vertebrae, respectively. For this purpose, two previously reported methods were combined: a deformable model-based initial segmentation method and a statistical shape-intensity model-based precise segmentation method. The former is used as a pre-processing to detect the position and orientation of each vertebra, which determines the initial condition for the latter precise segmentation method. The precise segmentation method needs prior knowledge on both the intensities and the shapes of the objects. After PCA analysis of such shape-intensity expressions obtained from training image sets, vertebrae were parametrically modeled as a linear combination of the principal component vectors. The segmentation of each target vertebra was performed as fitting of this parametric model to the target image by maximum a posteriori estimation, combined with the geodesic active contour method. In the experimental result by using 10 cases, the initial segmentation was successful in 6 cases and only partially failed in 4 cases (2 in the cervical area and 2 in the lumbo-sacral). In the precise segmentation, the mean error distances were 2.078, 1.416, 0.777, 0.939 mm for cervical, upper and lower thoracic, lumbar spines, respectively. In conclusion, our automatic segmentation algorithm for the vertebrae in human body CT images showed a fair performance for cervical, thoracic and lumbar vertebrae.

Predicting vertebral bone strength by vertebral static histomorphometry

DEFF Research Database (Denmark)

Thomsen, Jesper Skovhus; Ebbesen, Ebbe Nils; Mosekilde, Lis

2002-01-01

of the entire vertebral bodies (L-2) were used for histomorphometry. The other iliac crest biopsies and the L-3 were destructively tested by compression. High correlation was found between BV/TV or Tb.Sp and vertebral bone strength (absolute value of r = 0.86 in both cases). Addition of Tb.Th significantly....... No gender-related differences were found in any of the relationships. Neither static histomorphometry nor biomechanical testing of iliac crest bone biopsies is a good predictor of vertebral bone strength.......The study investigates the relationship between static histomorphometry and bone strength of human lumbar vertebral bone. The ability of vertebral histomorphometry to predict vertebral bone strength was compared with that of vertebral densitometry, and also with histomorphometry and bone strength...

Use of a Marine Vertebrate, the Flounder, in the Physiology Teaching Laboratory

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Bruce, David S.; Linden, Donald G.

1973-01-01

Describes two experiments in physiology using a readily available marine vertebrate, the flounder. Representative results are presented from experiments which measure the effect of excess potassium on the flounder EKG, and the effect of temperature on heart rate of the starry flounder. (JR)

Computer aided vertebral visualization and analysis: a methodology using the sand rat, a small animal model of disc degeneration

Directory of Open Access Journals (Sweden)

Hanley Edward N

2003-03-01

Full Text Available Abstract Background The purpose of this study is to present an automated system that analyzes digitized x-ray images of small animal spines identifying the effects of disc degeneration. The age-related disc and spine degeneration that occurs in the sand rat (Psammomys obesus has previously been documented radiologically; selected representative radiographs with age-related changes were used here to develop computer-assisted vertebral visualization/analysis techniques. Techniques presented here have the potential to produce quantitative algorithms that create more accurate and informative measurements in a time efficient manner. Methods Signal and image processing techniques were applied to digitized spine x-ray images the spine was segmented, and orientation and curvature determined. The image was segmented based on orientation changes of the spine; edge detection was performed to define vertebral boundaries. Once vertebrae were identified, a number of measures were introduced and calculated to retrieve information on the vertebral separation/orientation and sclerosis. Results A method is described which produces computer-generated quantitative measurements of vertebrae and disc spaces. Six sand rat spine radiographs illustrate applications of this technique. Results showed that this method can successfully automate calculation and analysis of vertebral length, vertebral spacing, vertebral angle, and can score sclerosis. Techniques also provide quantitative means to explore the relation between age and vertebral shape. Conclusions This method provides a computationally efficient system to analyze spinal changes during aging. Techniques can be used to automate the quantitative processing of vertebral radiographic images and may be applicable to human and other animal radiologic models of the aging/degenerating spine.

Short segment myelitis as a first manifestation of neuromyelitis optica spectrum disorders.

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Huh, So-Young; Kim, Su-Hyun; Hyun, Jae-Won; Jeong, In Hye; Park, Min Su; Lee, Sang-Hyun; Kim, Ho Jin

2017-03-01

Some patients with neuromyelitis optica spectrum disorders (NMOSD) present with spinal cord lesions extending fewer than three vertebral segments (short transverse myelitis, STM), hindering an early diagnosis. We investigated the frequency and imaging characteristics of STM lesions in patients presenting with myelitis as an initial manifestation of NMOSD. Patients seen at three referral hospitals in Korea between June 2005 and March 2015 who met the following inclusion criteria were recruited for review: seropositivity for aquaporin-4 antibody, initial presentation with myelitis and spinal cord magnetic resonance imaging (MRI) performed within 1 month of initial myelitis onset. Of the 76 enrolled patients, 65 (85.5%) collectively had 69 longitudinally extensive transverse myelitis lesions, while the remaining 11 (14.5%) had a total of 15 STM lesions. Of the 15 STM lesions, 5 spanned 2.5 vertebral segments, 6 were continuous over two segments, 3 showed a length of 1.5 segments and 1 was confined to a single segment. On axial imaging, all of the STM lesions involved the central grey matter. These MRI findings suggested that STM does not preclude the possibility of an NMOSD diagnosis.

[Utility of nickel-titanium shape memory alloys of vertebral body reduction fixator with assisted distraction bar].

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Man, Yi; Zheng, Yue-huan; Cao, Peng; Chen, Bo; Zheng, Tao; Sun, Chang-hui; Lu, Jiong

2011-06-07

To test the nickel-titanium (Ni-Ti) shape memory alloys of vertebral body reduction fixator with assisted distraction bar for the treatment of traumatic and osteoporotic vertebral body fracture. A Ni-Ti shape memory alloys of vertebral body reduction fixator with assisted distraction bar was implanted into the compressed fracture specimens through vertebral pedicle with the radiographic monitoring to reduce the collapsed endplate as well as distract the compressed vertebral fracture. Radiographic film and computed tomographic reconstruction technique were employed to evaluate the effects of reduction and distraction. A biomechanic test machine was used to measure the fatigue and the stability of deformation of fixation segments. Relying on the effect of temperature shape memory, such an assembly could basically reduce the collapsed endplate as well as distract the compressed vertebral fracture. And when unsatisfied results of reduction and distraction occurred, its super flexibility could provide additional distraction strength. A Ni-Ti shape memory alloys of vertebral body reduction fixator with assisted distraction bar may provide effective endplate reduction, restore the vertebral height and the immediate biomechanic spinal stability. So the above assembly is indicated for the treatment of traumatic and osteoporotic vertebral body fracture.

Generation of a genetically encoded marker of rod photoreceptor outer segment growth and renewal

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John J. Willoughby

2011-10-01

Vertebrate photoreceptors are specialized light sensing neurons. The photoreceptor outer segment is a highly modified cilium where photons of light are transduced into a chemical and electrical signal. The outer segment has the typical cilary axoneme but, in addition, it has a large number of densely packed, stacked, intramembranous discs. The molecular and cellular mechanisms that contribute to vertebrate photoreceptor outer segment morphogenesis are still largely unknown. Unlike typical cilia, the outer segment is continuously regenerated or renewed throughout the life of the animal through the combined process of distal outer segment shedding and proximal outer segment growth. The process of outer segment renewal was discovered over forty years ago, but we still lack an understanding of how photoreceptors renew their outer segments and few, if any, molecular mechanisms that regulate outer segment growth or shedding have been described. Our lack of progress in understanding how photoreceptors renew their outer segments has been hampered by the difficulty in measuring rates of renewal. We have created a new method that uses heat-shock induction of a fluorescent protein that can be used to rapidly measure outer segment growth rates. We describe this method, the stable transgenic line we created, and the growth rates observed in larval and adult rod photoreceptors using this new method. This new method will allow us to begin to define the genetic and molecular mechanisms that regulate rod outer segment renewal, a crucial aspect of photoreceptor function and, possibly, viability.

Relationship between vertebral artery blood flow in different head positions and vertigo.

Science.gov (United States)

Araz Server, Ela; Edizer, Deniz Tuna; Yiğit, Özgür; Yasak, Ahmet Görkem; Erdim, Çağrı

2018-01-01

To identify the vertebral artery blood flow in different head positions in patients with positional vertigo with no specific diagnosis. Patients with history of vestibular symptoms associated with changes in head position were enrolled into the study. Healthy volunteers were evaluated as control group. Doppler ultrasonography examination of the cervical segment of the vertebral arteries was performed under three different head positions: (i) supine position, (ii) head hyperextended and rotated to the right side and (iii) head hyperextended and rotated to the left side. In the study group, right and left vertebral artery blood flow was significantly lower in the ipsilateral hyperextended position compared to standard supine position (respectively p = .014; p = .001), but did not differ significantly when compared between the standard supine and contralateral hyperextended positions (respectively = .959; p = .669). In the control group, left and right vertebral artery blood flow did not differ significantly when the head was hyperextended to the right or left sides compared to standard supine position (p > .05). Our data demonstrated that the etiology of vestibular complaints in patients with undiagnosed positional vertigo might be related to impairment in vertebral artery blood flow according to head positions.

Excessive nitrite affects zebrafish valvulogenesis through yielding too much NO signaling.

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Junbo Li

Full Text Available Sodium nitrite, a common food additive, exists widely not only in the environment but also in our body. Excessive nitrite causes toxicological effects on human health; however, whether it affects vertebrate heart valve development remains unknown. In vertebrates, developmental defects of cardiac valves usually lead to congenital heart disease. To understand the toxic effects of nitrite on valvulogenesis, we exposed zebrafish embryos with different concentrations of sodium nitrite. Our results showed that sodium nitrite caused developmental defects of zebrafish heart dose dependently. It affected zebrafish heart development starting from 36 hpf (hour post fertilization when heart initiates looping process. Comprehensive analysis on the embryos at 24 hpf and 48 hpf showed that excessive nitrite did not affect blood circulation, vascular network, myocardium and endocardium development. But development of endocardial cells in atrioventricular canal (AVC of the embryos at 48 hpf was disrupted by too much nitrite, leading to defective formation of primitive valve leaflets at 76 hpf. Consistently, excessive nitrite diminished expressions of valve progenitor markers including bmp4, has2, vcana and notch1b at 48 hpf. Furthermore, 3', 5'-cyclic guanosine monophosphate (cGMP, downstream of nitric oxide (NO signaling, was increased its level significantly in the embryos exposed with excessive nitrite and microinjection of soluble guanylate cyclase inhibitor ODQ (1H-[1], [2], [4]Oxadiazolo[4,3-a] quinoxalin-1-one, an antagonist of NO signaling, into nitrite-exposed embryos could partly rescue the cardiac valve malformation. Taken together, our results show that excessive nitrite affects early valve leaflet formation by producing too much NO signaling.

An Unusual Case of a Large Hematorrachis Associated with Multi-Level Osteoporotic Vertebral Compression Fractures; a Case Report

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T.V. Ravi Kumar

2015-04-01

Full Text Available Spinal epidural haemorrhage may present as back pain associated with radicular symptoms and can be a catastrophic clinical scenario with progression to paraplegia or even sudden death. Being a rare entity, it needs a high index ofclinical suspicion to diagnose it. Fractures have been documented as a cause of hematorrachis but such hematomas only extend to one or two vertebral segments. Large epidural hematomas are usually associated with conditions like bleeding diathesis, arterio-venous malformations, plasma cell myeloma, and non-Hodgkin’s lymphoma. Surgical management with immediate evacuation of the hematoma is the usual line of management in patients with neurological deficits. Though rare, monitored and careful conservative management can lead to recovery of neurological symptoms and resolution of the hematoma. We report a case of a very large post traumatic epidural hematorrchis extending to 11 vertebral segments from D3 to L1 vertebral bodies, who had a gradual spontaneous recovery.

Automatic segmentation of lumbar vertebrae in CT images

Science.gov (United States)

Kulkarni, Amruta; Raina, Akshita; Sharifi Sarabi, Mona; Ahn, Christine S.; Babayan, Diana; Gaonkar, Bilwaj; Macyszyn, Luke; Raghavendra, Cauligi

2017-03-01

Lower back pain is one of the most prevalent disorders in the developed/developing world. However, its etiology is poorly understood and treatment is often determined subjectively. In order to quantitatively study the emergence and evolution of back pain, it is necessary to develop consistently measurable markers for pathology. Imaging based measures offer one solution to this problem. The development of imaging based on quantitative biomarkers for the lower back necessitates automated techniques to acquire this data. While the problem of segmenting lumbar vertebrae has been addressed repeatedly in literature, the associated problem of computing relevant biomarkers on the basis of the segmentation has not been addressed thoroughly. In this paper, we propose a Random-Forest based approach that learns to segment vertebral bodies in CT images followed by a biomarker evaluation framework that extracts vertebral heights and widths from the segmentations obtained. Our dataset consists of 15 CT sagittal scans obtained from General Electric Healthcare. Our main approach is divided into three parts: the first stage is image pre-processing which is used to correct for variations in illumination across all the images followed by preparing the foreground and background objects from images; the next stage is Machine Learning using Random-Forests, which distinguishes the interest-point vectors between foreground or background; and the last step is image post-processing, which is crucial to refine the results of classifier. The Dice coefficient was used as a statistical validation metric to evaluate the performance of our segmentations with an average value of 0.725 for our dataset.

Evolution, Development and Function of Vertebrate Cone Oil Droplets

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Matthew B. Toomey

2017-12-01

Full Text Available To distinguish colors, the nervous system must compare the activity of distinct subtypes of photoreceptors that are maximally sensitive to different portions of the light spectrum. In vertebrates, a variety of adaptations have arisen to refine the spectral sensitivity of cone photoreceptors and improve color vision. In this review article, we focus on one such adaptation, the oil droplet, a unique optical organelle found within the inner segment of cone photoreceptors of a diverse array of vertebrate species, from fish to mammals. These droplets, which consist of neutral lipids and carotenoid pigments, are interposed in the path of light through the photoreceptor and modify the intensity and spectrum of light reaching the photosensitive outer segment. In the course of evolution, the optical function of oil droplets has been fine-tuned through changes in carotenoid content. Species active in dim light reduce or eliminate carotenoids to enhance sensitivity, whereas species active in bright light precisely modulate carotenoid double bond conjugation and concentration among cone subtypes to optimize color discrimination and color constancy. Cone oil droplets have sparked the curiosity of vision scientists for more than a century. Accordingly, we begin by briefly reviewing the history of research on oil droplets. We then discuss what is known about the developmental origins of oil droplets. Next, we describe recent advances in understanding the function of oil droplets based on biochemical and optical analyses. Finally, we survey the occurrence and properties of oil droplets across the diversity of vertebrate species and discuss what these patterns indicate about the evolutionary history and function of this intriguing organelle.

Operative and endovascular management of extracranial vertebral artery aneurysm in Ehlers-Danlos syndrome:a clinical dilemma--case report and literature review.

LENUS (Irish Health Repository)

Sultan, Sherif

2002-01-01

The most prevalent lesion of the vertebral artery is an atheromatous plaque located at its origin from the subclavian artery. A case of successful management of a symptomatic vertebral artery aneurysm due to Ehlers-Danlos syndrome is reported. The patient had asymptomatic posterior intracerebral artery dissection on the contralateral side. A common carotid artery to V-3 segment bypass using reversed saphenous vein graft was carried out. Avulsion of the V-2 segment occurred peroperatively and endovascular coil embolization of the vertebral artery aneurysm was performed. Endovascular equipment and training must be in the armamentarium of vascular surgeons as more complex cases are being treated, which demands new approaches for ultimate clinical success. This unique case outlines what might unexpectedly occur. Endovascular intervention as an adjuvant procedure provides a satisfactory outcome in what could have been a catastrophe.

Ancient Pbx-Hox signatures define hundreds of vertebrate developmental enhancers

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Parker Hugo J

2011-12-01

Full Text Available Abstract Background Gene regulation through cis-regulatory elements plays a crucial role in development and disease. A major aim of the post-genomic era is to be able to read the function of cis-regulatory elements through scrutiny of their DNA sequence. Whilst comparative genomics approaches have identified thousands of putative regulatory elements, our knowledge of their mechanism of action is poor and very little progress has been made in systematically de-coding them. Results Here, we identify ancient functional signatures within vertebrate conserved non-coding elements (CNEs through a combination of phylogenetic footprinting and functional assay, using genomic sequence from the sea lamprey as a reference. We uncover a striking enrichment within vertebrate CNEs for conserved binding-site motifs of the Pbx-Hox hetero-dimer. We further show that these predict reporter gene expression in a segment specific manner in the hindbrain and pharyngeal arches during zebrafish development. Conclusions These findings evoke an evolutionary scenario in which many CNEs evolved early in the vertebrate lineage to co-ordinate Hox-dependent gene-regulatory interactions that pattern the vertebrate head. In a broader context, our evolutionary analyses reveal that CNEs are composed of tightly linked transcription-factor binding-sites (TFBSs, which can be systematically identified through phylogenetic footprinting approaches. By placing a large number of ancient vertebrate CNEs into a developmental context, our findings promise to have a significant impact on efforts toward de-coding gene-regulatory elements that underlie vertebrate development, and will facilitate building general models of regulatory element evolution.

Parallel fuzzy connected image segmentation on GPU

OpenAIRE

Zhuge, Ying; Cao, Yong; Udupa, Jayaram K.; Miller, Robert W.

2011-01-01

Purpose: Image segmentation techniques using fuzzy connectedness (FC) principles have shown their effectiveness in segmenting a variety of objects in several large applications. However, one challenge in these algorithms has been their excessive computational requirements when processing large image datasets. Nowadays, commodity graphics hardware provides a highly parallel computing environment. In this paper, the authors present a parallel fuzzy connected image segmentation algorithm impleme...

Evolution of vertebrate adaptive immunity: immune cells and tissues, and AID/APOBEC cytidine deaminases.

Science.gov (United States)

Hirano, Masayuki

2015-08-01

All surviving jawed vertebrate representatives achieve diversity in immunoglobulin-based B and T cell receptors for antigen recognition through recombinatorial rearrangement of V(D)J segments. However, the extant jawless vertebrates, lampreys and hagfish, instead generate three types of variable lymphocyte receptors (VLRs) through a template-mediated combinatorial assembly of different leucine-rich repeat (LRR) sequences. The clonally diverse VLRB receptors are expressed by B-like lymphocytes, while the VLRA and VLRC receptors are expressed by lymphocyte lineages that resemble αβ and γδ T lymphocytes, respectively. These findings suggest that three basic types of lymphocytes, one B-like and two T-like, are an essential feature of vertebrate adaptive immunity. Around 500 million years ago, a common ancestor of jawed and jawless vertebrates evolved a genetic program for the development of prototypic lymphoid cells as a foundation for an adaptive immune system. This acquisition preceded the convergent evolution of alternative types of clonally diverse receptors for antigens in all vertebrates, as reviewed in this article. © 2015 WILEY Periodicals, Inc.

Three-dimensional motion pattern of the caudal lumbar and lumbosacral portions of the vertebral column of dogs.

Science.gov (United States)

Benninger, Monika I; Seiler, Gabriela S; Robinson, Leanne E; Ferguson, Stephen J; Bonél, Harald M; Busato, André R; Lang, Johann

2004-05-01

To evaluate the 3-dimensional motion pattern including main and coupled motions of the caudal lumbar and lumbosacral portions of the vertebral column of dogs. Vertebral columns of 9 German Shepherd Dogs (GSDs) and 16 dogs of other breeds with similar body weights and body conditions. Main and coupled motions of the caudal lumbar and lumbosacral portions of the vertebral column (L4 to S1) were determined by use of a testing apparatus that permitted precise application of known pure moments to the vertebral column. Motion was compared between GSDs and dogs of other breeds. All specimens had a similar motion pattern consisting of main motion and a certain amount of coupled motion including translation. Vertebral columns of GSDs had significantly less main motion in all directions than that of dogs of other breeds. Translation was similar in GSDs and dogs of other breeds and was smallest at the lumbosacral motion segment. Results indicated that motion in the caudal lumbar and lumbosacral portions of the vertebral column of dogs is complex and provided a basis for further studies evaluating abnormal vertebral columns.

Treatment Challenges of a Primary Vertebral Artery Aneurysm Causing Recurrent Ischemic Strokes

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Davide Strambo

2017-01-01

Full Text Available Background. Extracranial vertebral artery aneurysms are a rare cause of embolic stroke; surgical and endovascular therapy options are debated and long-term complication may occur. Case Report. A 53-year-old man affected by neurofibromatosis type 1 (NF1 came to our attention for recurrent vertebrobasilar embolic strokes, caused by a primary giant, partially thrombosed, fusiform aneurysm of the left extracranial vertebral artery. The aneurysm was treated by endovascular approach through deposition of Guglielmi Detachable Coils in the proximal segment of the left vertebral artery. Six years later the patient presented stroke recurrence. Cerebral angiography and Color Doppler Ultrasound well characterized the unique hemodynamic condition developed over the years responsible for the new embolic event: the aneurysm had been revascularized from its distal portion by reverse blood flow coming from the patent vertebrobasilar axis. A biphasic Doppler signal in the left vertebral artery revealed a peculiar behavior of the blood flow, alternately directed to the aneurysm and backwards to the basilar artery. Surgical ligation of the distal left vertebral artery and excision of the aneurysm were thus performed. Conclusion. This is the first described case of NF1-associated extracranial vertebral artery aneurysm presenting with recurrent embolic stroke. Complete exclusion of the aneurysm from the blood circulation is advisable to achieve full resolution of the embolic source.

Three-dimensional vertebral wedging in mild and moderate adolescent idiopathic scoliosis.

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Sophie-Anne Scherrer

Full Text Available Vertebral wedging is associated with spinal deformity progression in adolescent idiopathic scoliosis. Reporting frontal and sagittal wedging separately could be misleading since these are projected values of a single three-dimensional deformation of the vertebral body. The objectives of this study were to determine if three-dimensional vertebral body wedging is present in mild scoliosis and if there are a preferential vertebral level, position and plane of deformation with increasing scoliotic severity.Twenty-seven adolescent idiopathic scoliotic girls with mild to moderate Cobb angles (10° to 50° participated in this study. All subjects had at least one set of bi-planar radiographs taken with the EOS® X-ray imaging system prior to any treatment. Subjects were divided into two groups, separating the mild (under 20° from the moderate (20° and over spinal scoliotic deformities. Wedging was calculated in three different geometric planes with respect to the smallest edge of the vertebral body.Factorial analyses of variance revealed a main effect for the scoliosis severity but no main effect of vertebral Levels (apex and each of the three vertebrae above and below it (F = 1.78, p = 0.101. Main effects of vertebral Positions (apex and above or below it (F = 4.20, p = 0.015 and wedging Planes (F = 34.36, p<0.001 were also noted. Post-hoc analysis demonstrated a greater wedging in the inferior group of vertebrae (3.6° than the superior group (2.9°, p = 0.019 and a significantly greater wedging (p≤0.03 along the sagittal plane (4.3°.Vertebral wedging was present in mild scoliosis and increased as the scoliosis progressed. The greater wedging of the inferior group of vertebrae could be important in estimating the most distal vertebral segment to be restrained by bracing or to be fused in surgery. Largest vertebral body wedging values obtained in the sagittal plane support the claim that scoliosis could be initiated

Vertebral compression fractures after spine irradiation using conventional fractionation in patients with metastatic colorectal cancer

Energy Technology Data Exchange (ETDEWEB)

Ree, Woo Joong; Kim, Kyung Hwan; Chang, Jee Suk; Kim, Hyun Ju; Choi, Seo Hee; Koom, Woong Sub [Dept.of Radiation Oncology, Yonsei Cancer Center, Yonsei University Health System, Seoul (Korea, Republic of)

2014-12-15

To evaluate the risk of vertebral compression fracture (VCF) after conventional radiotherapy (RT) for colorectal cancer (CRC) with spine metastasis and to identify risk factors for VCF in metastatic and non-metastatic irradiated spines. We retrospectively reviewed 68 spinal segments in 16 patients who received conventional RT between 2009 and 2012. Fracture was defined as a newly developed VCF or progression of an existing fracture. The target volume included all metastatic spinal segments and one additional non-metastatic vertebra adjacent to the tumor-involved spines. The median follow-up was 7.8 months. Among all 68 spinal segments, there were six fracture events (8.8%) including three new VCFs and three fracture progressions. Observed VCF rates in vertebral segments with prior irradiation or pre-existing compression fracture were 30.0% and 75.0% respectively, compared with 5.2% and 4.7% for segments without prior irradiation or pre-existing compression fracture, respectively (both p < 0.05). The 1-year fracture-free probability was 87.8% (95% CI, 78.2-97.4). On multivariate analysis, prior irradiation (HR, 7.30; 95% CI, 1.31-40.86) and pre-existing compression fracture (HR, 18.45; 95% CI, 3.42-99.52) were independent risk factors for VCF. The incidence of VCF following conventional RT to the spine is not particularly high, regardless of metastatic tumor involvement. Spines that received irradiation and/or have pre-existing compression fracture before RT have an increased risk of VCF and require close observation.

Interplay between a Wnt-dependent organiser and the Notch segmentation clock regulates posterior development in Periplaneta americana

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John E. Chesebro

2012-12-01

Sequential addition of segments in the posteriorly growing end of the embryo is a developmental mechanism common to many bilaterians. However, posterior growth and patterning in most animals also entails the establishment of a ‘posterior organiser’ that expresses the Caudal and Wnt proteins and has been proposed to be an ancestral feature of animal development. We have studied the functional relationships between the Wnt-driven organiser and the segmentation mechanisms in a basal insect, the cockroach Periplaneta americana. Here, posteriorly-expressed Wnt1 promotes caudal and Delta expression early in development to generate a growth zone from which segments will later bud off. caudal maintains the undifferentiated growth zone by dampening Delta expression, and hence Notch-mediated segmentation occurs just outside the caudal domain. In turn, Delta expression maintains Wnt1, maintaining this posterior gene network until all segments have formed. This feedback between caudal, Wnt and Notch-signalling in regulating growth and segmentation seems conserved in other arthropods, with some aspects found even in vertebrates. Thus our findings not only support an ancestral Wnt posterior organiser, but also impinge on the proposals for a common origin of segmentation in arthropods, annelids and vertebrates.

Extensive molecular differences between anterior- and posterior-half-sclerotomes underlie somite polarity and spinal nerve segmentation

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Keynes Roger J

2009-05-01

Full Text Available Abstract Background The polarization of somite-derived sclerotomes into anterior and posterior halves underlies vertebral morphogenesis and spinal nerve segmentation. To characterize the full extent of molecular differences that underlie this polarity, we have undertaken a systematic comparison of gene expression between the two sclerotome halves in the mouse embryo. Results Several hundred genes are differentially-expressed between the two sclerotome halves, showing that a marked degree of molecular heterogeneity underpins the development of somite polarity. Conclusion We have identified a set of genes that warrant further investigation as regulators of somite polarity and vertebral morphogenesis, as well as repellents of spinal axon growth. Moreover the results indicate that, unlike the posterior half-sclerotome, the central region of the anterior-half-sclerotome does not contribute bone and cartilage to the vertebral column, being associated instead with the development of the segmented spinal nerves.

The segmentation of the human brain; a message to the neuroimaging community from an adjacent domain of the neurosciences

NARCIS (Netherlands)

Nieuwenhuys, R.

2018-01-01

Morphological and genoarchitectonic studies have conclusively shown that the human brain (and that of all vertebrates) is segmented i. e. is fundamentally composed of a number of rostrocaudally arranged brain segments or neuromeres. However in the current neuroimaging literature the term

Are spinal or paraspinal anatomic makers helpful for vertebral numbering and diagnosing lumbosacral transitional vertebrae?

Energy Technology Data Exchange (ETDEWEB)

Tokgoz, Nil; Ucar, Murat; Erdogan, Aylin Billur; Killic, Koray; Ozcan, Cahide [Dept. of Radiology, Gazi University School of Medicine, Ankara (Turkmenistan)

2014-04-15

To evaluate the value of spinal and paraspinal anatomic markers in both the diagnosis of lumbosacral transitional vertebrae (LSTVs) and identification of vertebral levels on lumbar MRI. Lumbar MRI from 1049 adult patients were studied. By comparing with the whole-spine localizer, the diagnostic errors in numbering vertebral segments on lumbar MRI were evaluated. The morphology of S1-2 disc, L5 and S1 body, and lumbar spinous processes (SPs) were evaluated by using sagittal MRI. The positions of right renal artery (RRA), superior mesenteric artery, aortic bifurcation (AB) and conus medullaris (CM) were described. The diagnostic error for evaluation of vertebral segmentation on lumbar MRI alone was 14.1%. In lumbarization, all patients revealed a well-formed S1-2 disc with squared S1 body. A rhombus-shaped L5 body in sacralization and a rectangular-shaped S1 body in lumbarization were found. The L3 had the longest SP. The most common sites of spinal and paraspinal structures were: RRA at L1 body (53.6%) and L1-2 disc (34.1%), superior mesenteric artery at L1 body (55.1%) and T12-L1 disc (31.6%), and AB at L4 body (71.1%). CM had variable locations, changing from the T12-L1 disc to L2 body. They were located at higher sacralization and lower lumbarization. The spinal morphologic features and locations of the spinal and paraspinal structures on lumbar MRI are not completely reliable for the diagnosis of LSTVs and identification on the vertebral levels.

Angioplasty or Stenting of Extra- and Intracranial Vertebral Artery Stenoses

International Nuclear Information System (INIS)

Hauth, Elke A.M.; Gissler, H. Martin; Drescher, Robert; Jansen, Christian; Jaeger, Horst J.; Mathias, Klaus D.

2004-01-01

Purpose: To determine the feasibility and safety of angioplasty or angioplasty and stenting of extra- and intracranial vertebral artery (VA) stenosis. Methods: In 16 consecutive patients (9 men, 7 women; mean age 61 years, range 49-74 years) 16 stenotic VAs were treated with angioplasty orangioplasty and stenting. Eleven stenoses were localized in V1 segment,1 stenosis in V2 segment and 4 stenoses in V4 segment of VA. Fourteen VA stenoses were symptomatic, 2 asymptomatic. The etiology of the stenoses was atherosclerotic in all cases. Results:Angioplasty was performed in 8 of 11 V1 and 2 of 4 V4 segments of the VA. In 3 of 11 V1 segments and 2 of 4 V4 segments of the VA we combined angioplasty with stenting. The procedures were successfully performed in 14 of 16 VAs (87%). Complications were asymptomatic vessel dissection resulting in vessel occlusion in 1 of 11 V1 segments and asymptomatic vessel dissection in 2 of 4 V4 segments of the VA. One patient died in the 24-hr period after the procedure because of subarachnoid hemorrhage as a complication following vessel perforation of the treated V4 segment. Conclusion: Angioplasty orangioplasty and stenting of extracranial VA stenoses can be performed with a high technical success rate and a low complication rate. In intracranial VA stenosis the procedure is technically feasible but complications can be life-threatening. The durability and procedural complication rates of primary stenting without using predilation in extra- and intracranial VA stenosis should be defined in the future

Delayed vertebral diagnosed L4 pincer vertebral fracture, L2-L3 ruptured vertebral lumbar disc hernia, L5 vertebral wedge fracture - Case report

OpenAIRE

Balasa D; Schiopu M; Tunas A; Baz R; Hancu Anca

2016-01-01

An association between delayed ruptured lumbar disc hernia, L5 vertebral wedge fracture and posttraumaticL4 pincer vertebral fracture (A2.3-AO clasification) at different levels is a very rare entity. We present the case of a 55 years old male who falled down from a bicycle. 2 months later because of intense and permanent vertebral lumbar and radicular L2 and L3 pain (Visual Scal Autologus of Pain7-8/10) the patient came to the hospital. He was diagnosed with pincer vertebral L4 fracture (A2....

C1-C2 instability with severe occipital headache in the setting of vertebral artery facet complex erosion.

Science.gov (United States)

Taher, Fadi; Bokums, Kristaps; Aichmair, Alexander; Hughes, Alexander P

2014-05-01

An exact understanding of patient vertebral artery anatomy is essential to safely place screws at the atlanto-axial level in posterior arthrodesis. We aim to report a case of erosion of the left vertebral artery into the C1-C2 facet complex with resultant rotatory and lateral listhesis presenting with severe occipital headache. This represents a novel etiology for this diagnosis and our report illustrates technical considerations when instrumenting the C1-C2 segment. We report a case of severe occipital headache due to C1-C2 instability with resultant left C2 nerve compression in the setting of erosion of the vertebral artery into the C1-C2 facet complex. A 68-year-old woman presented with a 12-month history of progressively debilitating headache and neck pain with atlanto-axial instability. Computed tomography (CT) angiography demonstrated erosion of the left vertebral artery into the left C1-C2 facet complex. In addition, the tortuous vertebral arteries had eroded into the C2 pedicles, eliminating the possibility for posterior pedicle screw placement. The patient underwent posterior arthrodesis of C1-C2 utilizing bilateral lateral mass fixation into C1 and bilateral trans-laminar fixation into C2 with resolution of all preoperative complaints. This study constitutes the first report of a tortuous vertebral artery causing the partial destruction of a C1-C2 facet complex, as well as instability, with the clinical presentation of severe occipital headache. It hereby presents a novel etiology for both the development of C1-C2 segment instability as well as the development of occipital headache. Careful evaluation of such lesions utilizing CT angiography is important when formulating a surgical plan.

Developmental identity versus typology: Lucy has only four sacral segments.

Science.gov (United States)

Machnicki, Allison L; Lovejoy, C Owen; Reno, Philip L

2016-08-01

Both interspecific and intraspecific variation in vertebral counts reflect the action of patterning control mechanisms such as Hox. The preserved A.L. 288-1 ("Lucy") sacrum contains five fused elements. However, the transverse processes of the most caudal element do not contact those of the segment immediately craniad to it, leaving incomplete sacral foramina on both sides. This conforms to the traditional definition of four-segmented sacra, which are very rare in humans and African apes. It was recently suggested that fossilization damage precludes interpretation of this specimen and that additional sacral-like features of its last segment (e.g., the extent of the sacral hiatus) suggest a general Australopithecus pattern of five sacral vertebrae. We provide updated descriptions of the original Lucy sacrum. We evaluate sacral/coccygeal variation in a large sample of extant hominoids and place it within the context of developmental variation in the mammalian vertebral column. We report that fossilization damage did not shorten the transverse processes of the fifth segment of Lucy's sacrum. In addition, we find that the extent of the sacral hiatus is too variable in apes and hominids to provide meaningful information on segment identity. Most importantly, a combination of sacral and coccygeal features is to be expected in vertebrae at regional boundaries. The sacral/caudal boundary appears to be displaced cranially in early hominids relative to extant African apes and humans, a condition consistent with the likely ancestral condition for Miocene hominoids. While not definitive in itself, a four-segmented sacrum accords well with the "long-back" model for the Pan/Homo last common ancestor. Am J Phys Anthropol 160:729-739, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Localization of Proliferating Cells in the Inter-Vertebral Region of the Developing and Adult Vertebrae of Lizards in Relation to Growth and Regeneration.

Science.gov (United States)

Alibardi, Lorenzo

2016-04-01

New cartilaginous tissues in lizards is formed during the regeneration of the tail or after vertebral damage. In order to understand the origin of new cartilaginous cells in the embryo and after injury of adult vertebrae we have studied the distribution of proliferating cartilaginous cells in the vertebral column of embryos and adults of the lizard Anolis lineatopus using autoradiography for H3-thymidine and light and ultrastructural immunocytochemistry for 5BrdU. Proliferating sclerotomal cells initially surround the notochord in a segmental pattern and give rise to the chondrocytes of the vertebral centrum that replace the original chordal cells. Qualitative observations show that proliferating sclerotomal cells dilute the labeling up to 13 days post-injection but a few maintain the labeling as long labeling retention cells and remain in the inter-centra and perichondrium after birth. These cells supply new chondroblasts for post-natal growth of vertebrae but can also proliferate in case of vertebral damage or tail amputation in lizards, a process that sustains tail regeneration. The lack of somitic organization in the regenerating tail impedes the re-formation of a segmental vertebral column that is instead replaced by a continuous cartilaginous tube. It is hypothesized that long labeling retaining cells might represent stem/primordial cells, and that their permanence in the inter-vertebral cartilages and the nearby perichondrium in adult lizards pre-adapt these reptiles to elicit a broad cartilage regeneration in case of injury of the vertebrae. © 2016 Wiley Periodicals, Inc.

The deformation behavior of the cervical spine segment

Science.gov (United States)

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

2017-09-01

The paper describes the model of the cervical spine segment (C3-C4) and the calculation results of its deformation behavior at flexion. 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. Degenerative changes of the intervertebral disk (IVD) were simulated through a reduction of the disc height and an increase of Young's modulus. The construction of the geometric model of the cervical spine segment and the calculations of the stress-strain state were carried out in the ANSYS software complex. The calculation results show that the biggest protrusion of the IVD in bending direction of segment is observed when IVD height is reduced. The disc protrusion is reduced with an increase of Young's modulus. The largest protrusion in the direction of flexion of the segment is the intervertebral disk with height of 4.3 mm and elastic modulus of 2.5 MPa. The results of the study can be useful to specialists in the field of biomechanics, medical materials science and prosthetics.

The cat vertebral column: stance configuration and range of motion

Science.gov (United States)

Macpherson, J. M.; Ye, Y.; Peterson, B. W. (Principal Investigator)

1998-01-01

This study examined the configuration of the vertebral column of the cat during independent stance and in various flexed positions. The range of motion in the sagittal plane is similar across most thoracic and lumbar joints, with the exception of a lesser range at the transition region from thoracic-type to lumbar-type vertebrae. The upper thoracic column exhibits most of its range in dorsiflexion and the lower thoracic and lumbar in ventroflexion. Lateral flexion is limited to less than 5 degrees at all segments. The range in torsion is almost 180 degrees and occurs primarily in the midthoracic region, T4-T11. Contrary to the depiction in most atlases, the standing cat exhibits several curvatures, including a mild dorsiflexion in the lower lumbar segments, a marked ventroflexion in the lower thoracic and upper lumbar segments, and a profound dorsiflexion in the upper thoracic (above T9) and cervical segments. The curvatures are not significantly changed by altering stance distance but are affected by head posture. During stance, the top of the scapula lies well above the spines of the thoracic vertebrae, and the glenohumeral joint is just below the bodies of vertebrae T3-T5. Using a simple static model of the vertebral column in the sagittal plane, it was estimated that the bending moment due to gravity is bimodal with a dorsiflexion moment in the lower thoracic and lumbar region and a ventroflexion moment in the upper thoracic and cervical region. Given the bending moments and the position of the scapula during stance, it is proposed that two groups of scapular muscles provide the major antigravity support for the head and anterior trunk. Levator scapulae and serratus ventralis form the lateral group, inserting on the lateral processes of cervical vertebrae and on the ribs. The major and minor rhomboids form the medial group, inserting on the spinous tips of vertebrae from C4 to T4. It is also proposed that the hypaxial muscles, psoas major, minor, and quadratus

Vertebrate sex-determining genes play musical chairs.

Science.gov (United States)

Pan, Qiaowei; Anderson, Jennifer; Bertho, Sylvain; Herpin, Amaury; Wilson, Catherine; Postlethwait, John H; Schartl, Manfred; Guiguen, Yann

2016-01-01

Sexual reproduction is one of the most highly conserved processes in evolution. However, the genetic and cellular mechanisms making the decision of whether the undifferentiated gonad of animal embryos develops either towards male or female are manifold and quite diverse. In vertebrates, sex-determining mechanisms range from environmental to simple or complex genetic mechanisms and different mechanisms have evolved repeatedly and independently. In species with simple genetic sex-determination, master sex-determining genes lying on sex chromosomes drive the gonadal differentiation process by switching on a developmental program, which ultimately leads to testicular or ovarian differentiation. So far, very few sex-determining genes have been identified in vertebrates and apart from mammals and birds, these genes are apparently not conserved over a larger number of related orders, families, genera, or even species. To fill this knowledge gap and to better explore genetic sex-determination, we propose a strategy (RAD-Sex) that makes use of next-generation sequencing technology to identify genetic markers that define sex-specific segments of the male or female genome. Copyright © 2016 Académie des sciences. All rights reserved.

V. Terrestrial vertebrates

Science.gov (United States)

Dean Pearson; Deborah Finch

2011-01-01

Within the Interior West, terrestrial vertebrates do not represent a large number of invasive species relative to invasive weeds, aquatic vertebrates, and invertebrates. However, several invasive terrestrial vertebrate species do cause substantial economic and ecological damage in the U.S. and in this region (Pimental 2000, 2007; Bergman and others 2002; Finch and...

Novel ENU-Induced Mutation in Tbx6 Causes Dominant Spondylocostal Dysostosis-Like Vertebral Malformations in the Rat.

Science.gov (United States)

Abe, Koichiro; Takamatsu, Nobuhiko; Ishikawa, Kumiko; Tsurumi, Toshiko; Tanimoto, Sho; Sakurai, Yukina; Lisse, Thomas S; Lisse, Thomas; Imai, Kenji; Serikawa, Tadao; Mashimo, Tomoji

2015-01-01

Congenital vertebral malformations caused by embryonic segmentation defects are relatively common in humans and domestic animals. Although reverse genetics approaches in mice have provided information on the molecular mechanisms of embryonic somite segmentation, hypothesis-driven approaches cannot adequately reflect human dysmorphology within the population. In a N-ethyl-N-nitrosourea (ENU) mutagenesis project in Kyoto, the Oune mutant rat strain was isolated due to a short and kinked caudal vertebra phenotype. Skeletal staining of heterozygous rats showed partial loss of the cervical vertebrae as well as hemivertebrae and fused vertebral blocks in lumbar and sacral vertebrae. In homozygous embryos, severe displacement of the whole vertebrae was observed. The Oune locus was genetically mapped to rat chromosome 1 using 202 backcross animals and 50 genome-wide microsatellite markers. Subsequently, a miss-sense mutation in the Tbx6 gene was identified in the critical region. Although the mutation is located within the T-box domain near a predicted dimmer-interface, in vitro experiments revealed that the Tbx6 variant retains normal DNA binding ability and translational efficiency. However, the variant has decreased transcriptional activation potential in response to Notch-mediated signaling. Recently, it was reported that a dominant type of familial spondylocostal dysostosis is caused by a stoploss mutation in TBX6. Thus, we propose that partial dysfunction of Tbx6 leads to similar congenital vertebral malformations in both humans and rats. The Oune strain could be a unique animal model for dominant spondylocostal dysostosis and is useful for molecular dissection of the pathology of congenital vertebral malformations in humans.

Novel ENU-Induced Mutation in Tbx6 Causes Dominant Spondylocostal Dysostosis-Like Vertebral Malformations in the Rat.

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Koichiro Abe

Full Text Available Congenital vertebral malformations caused by embryonic segmentation defects are relatively common in humans and domestic animals. Although reverse genetics approaches in mice have provided information on the molecular mechanisms of embryonic somite segmentation, hypothesis-driven approaches cannot adequately reflect human dysmorphology within the population. In a N-ethyl-N-nitrosourea (ENU mutagenesis project in Kyoto, the Oune mutant rat strain was isolated due to a short and kinked caudal vertebra phenotype. Skeletal staining of heterozygous rats showed partial loss of the cervical vertebrae as well as hemivertebrae and fused vertebral blocks in lumbar and sacral vertebrae. In homozygous embryos, severe displacement of the whole vertebrae was observed. The Oune locus was genetically mapped to rat chromosome 1 using 202 backcross animals and 50 genome-wide microsatellite markers. Subsequently, a miss-sense mutation in the Tbx6 gene was identified in the critical region. Although the mutation is located within the T-box domain near a predicted dimmer-interface, in vitro experiments revealed that the Tbx6 variant retains normal DNA binding ability and translational efficiency. However, the variant has decreased transcriptional activation potential in response to Notch-mediated signaling. Recently, it was reported that a dominant type of familial spondylocostal dysostosis is caused by a stoploss mutation in TBX6. Thus, we propose that partial dysfunction of Tbx6 leads to similar congenital vertebral malformations in both humans and rats. The Oune strain could be a unique animal model for dominant spondylocostal dysostosis and is useful for molecular dissection of the pathology of congenital vertebral malformations in humans.

Repeated adjacent-segment degeneration after posterior lumbar interbody fusion.

Science.gov (United States)

Okuda, Shinya; Oda, Takenori; Yamasaki, Ryoji; Maeno, Takafumi; Iwasaki, Motoki

2014-05-01

One of the most important sequelae affecting long-term results is adjacent-segment degeneration (ASD) after posterior lumbar interbody fusion (PLIF). Although several reports have described the incidence rate, there have been no reports of repeated ASD. The purpose of this report was to describe 1 case of repeated ASD after PLIF. A 62-year-old woman with L-4 degenerative spondylolisthesis underwent PLIF at L4-5. At the second operation, L3-4 PLIF was performed for L-3 degenerative spondylolisthesis 6 years after the primary operation. At the third operation, L2-3 PLIF was performed for L-2 degenerative spondylolisthesis 1.5 years after the primary operation. Vertebral collapse of L-1 was detected 1 year after the third operation, and the collapse had progressed. At the fourth operation, 3 years after the third operation, vertebral column resection of L-1 and replacement of titanium mesh cages with pedicle screw fixation between T-4 and L-5 was performed. Although the patient's symptoms resolved after each operation, the time between surgeries shortened. The sacral slope decreased gradually although each PLIF achieved local lordosis at the fused segment.

CT study of vertebral metastasis: re-realization of the diagnostic role of the vertebral pedicle sign

International Nuclear Information System (INIS)

Meng Quanfei; Jiang Bo; Chen Yingming; Zhang Chaohui

2000-01-01

Objective: To investigate the essence of the vertebral pedicle sign of vertebral metastasis on plain film, and to explore the useful CT signs for the diagnosis and differential diagnosis of this tumor. Methods: The CT scans of the spine obtained in 48 patients with vertebral metastases, 19 patients with vertebral tuberculosis, and 11 with vertebral myeloma, were analyzed. The CT findings were correlated with the abnormalities seen on plain films in 34 of the 48 patients (66 vertebrae involved) with vertebral metastasis. Results: 66 vertebrae were involved in the group of metastasis. Of the 28 vertebrae whose vertebral body were completely destroyed, 15 were seen bilateral pedicles destruction; Of the 22 vertebrae with lateral destruction of the body, 16 were noticed unilateral pedicle destruction which located posterior to the involved side of the body. Of the 62 micro-metastatic foci, 56 were scattered in the vertebral body. In the 19 para-spinal soft-tissue masses of vertebral tuberculosis, 5 were noticed calcifications and 12 with postcontrast rings enhancement. The rates of vertebral pedicle destruction of vertebral metastasis and myeloma were not statistically different (X 2 = 0.03, P > 0.50). The locations of destruction of vertebral body in vertebral metastasis and myeloma had no statistical difference (X 2 = 3.52, P > 0.10), but they differed from that in tuberculosis (X 2 = 39.32, P < 0.001). The distribution of lesions within the vertebrae of metastasis and tuberculosis was similar, but was quite different from myeloma. Conclusion: The vertebral metastasis initially occurs in the vertebral body. The vertebral pedicle sign on plain film of vertebral metastasis is the outcome of the posterior invasion of the tumor in the vertebral body, which is of no differential significance for vertebral metastasis and myeloma. Para-spinal soft tissue mass, location of destruction of vertebral body, and the distribution of lesions within the vertebrae may help

Mielodisplasia segmentar múltipla em gato Multiple segmental myelodysplasia in cat

Directory of Open Access Journals (Sweden)

Eduardo Alberto Tudury

2000-06-01

Full Text Available Relata-se o caso de uma gata Siamês de seis meses de idade que desde o nascimento apresentava paraplegia espástica associada à incontinência fecal e urinária. No exame neurológico, exibia paralisia, analgesia, hiperreflexia e perda das reações posturais nos membros posteriores. Radiografias simples e contrastadas (mielografia da coluna vertebral toracolombar evidenciaram estreitamentos do canal vertebral na região lombar e da medula espinhal, vértebras torácicas e lombares. Na necropsia e exame histopatológico, verificou-se hipoplasia segmentar caracterizada pelo afinamento localizado da medula espinhal em T4-T6 e L2-L3, depleção neuronal na substância cinzenta e filetes nervosos interligando as partes craniais e caudais, todos recobertos por dura mater íntegra e espessada. Essas alterações permitiram concluir o diagnóstico de mielodisplasia segmentar múltipla.A 6 month old female siamese cat presented since birth spastic paraplegy associated to urinary and fecal incontinence. The neurological examination showed paralysis, analgesia, increased reflexes and damage of the postural reaction in pelvic limbs. Simple and contrasted (myelography radiography of the thoracolumbar vertebral column showed a lumbar vertebral canal stenosis and narrowing of the spinal cord on thoracic and lumbar vertebrae. On necropsy and histopathology examination it was observed a segmental hypoplasia characterized for narrowing of the spinal cord in T4-T6 and L2-L3, neuronal depletion in gray substance, and nervous filaments connecting the cranial and caudal parts that was covered for entire and dense dura mater. This alteration characteristic a multiple segmental myelodysplasia.

Vertebral derotation in adolescent idiopathic scoliosis causes hypokyphosis of the thoracic spine

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Watanabe Kota

2012-06-01

Full Text Available Abstract Background The purpose of this study was to test the hypothesis that direct vertebral derotation by pedicle screws (PS causes hypokyphosis of the thoracic spine in adolescent idiopathic scoliosis (AIS patients, using computer simulation. Methods Twenty AIS patients with Lenke type 1 or 2 who underwent posterior correction surgeries using PS were included in this study. Simulated corrections of each patient’s scoliosis, as determined by the preoperative CT scan data, were performed on segmented 3D models of the whole spine. Two types of simulated extreme correction were performed: 1 complete coronal correction only (C method and 2 complete coronal correction with complete derotation of vertebral bodies (C + D method. The kyphosis angle (T5-T12 and vertebral rotation angle at the apex were measured before and after the simulated corrections. Results The mean kyphosis angle after the C + D method was significantly smaller than that after the C method (2.7 ± 10.0° vs. 15.0 ± 7.1°, p  Conclusions In the 3D simulation study, kyphosis was reduced after complete correction of the coronal and rotational deformity, but it was maintained after the coronal-only correction. These results proved the hypothesis that the vertebral derotation obtained by PS causes hypokyphosis of the thoracic spine.

Vertebral osteomyelitis without disc involvement

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Kamani, I.; Syed, I.; Saifuddin, A. E-mail: asaifuddin@aol.com; Green, R.; MacSweeney, F

2004-10-01

Vertebral osteomyelitis is most commonly due to pyogenic or granulomatous infection and typically results in the combined involvement of the intervertebral disc and adjacent vertebral bodies. Non-infective causes include the related conditions of chronic recurrent multifocal osteomyelitis (CRMO) and SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome. Occasionally, these conditions may present purely within the vertebral body, resulting in various combinations of vertebral marrow oedema and sclerosis, destructive lesions of the vertebral body and pathological vertebral collapse, thus mimicking neoplastic disease. This review illustrates the imaging features of vertebral osteomyelitis without disc involvement, with emphasis on magnetic resonance imaging (MRI) findings.

Primary Ewing's sarcoma of the vertebral column

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Ilaslan, Hakan; Sundaram, Murali [Department of Radiology, Mayo Clinic, Ch2-290 200 First Street, SW, Rochester, 55905, MN (United States); Unni, K.Krishnan [Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 First Street, SW, 55905, Rochester, MN (United States); Dekutoski, Mark B. [Department of Orthopedic Surgery, Mayo Clinic, 200 First Street, SW, 55905, Rochester, MN (United States)

2004-09-01

To determine the demographics, imaging findings, clinical symptoms, and prognosis of primary vertebral Ewing's sarcoma (PVES). A retrospective review of medical records and radiological studies of patients diagnosed with PVES from 1936 through 2001 in our institution and Department of Pathology consultation files was undertaken. Metastatic and soft tissue Ewing's sarcoma cases were excluded. From a total of 1,277 cases of Ewing's sarcoma, 125 (9.8%) had a primary vertebral origin. There were 48 females and 76 males. Patient ages ranged from 4 to 54 (mean 19.3, standard deviation 10.7, median 16) years. Vertebral column distribution was four cervical (3.2%), 13 thoracic (10.5%), 31 lumbar (25%), and 67 sacrum (53.2%). More than one vertebral segment was involved in ten cases (8%). Satisfactory imaging studies were available in 51 patients: 49 radiographs, 27 computerized tomography (CT), and 23 magnetic resonance imaging (MRI) studies. The majority of tumors were lytic (93%). Three cases were mixed lytic and sclerotic (6%) and one sclerotic. In the nonsacral spine, the majority of lesions (12/20) involved the posterior elements with extension into the vertebral body. Five cases were centered in the vertebral body with extension into the posterior elements. Two cases were limited to the posterior elements, and one case solely involved the vertebral body. Ala was the most frequently affected site in the sacrum (18/26). Spinal canal invasion was frequent (91%). Detailed clinical information was available in 53 patients. Duration of symptoms ranged from 1 to 30 (mean 7) months. Local pain was the first symptom and seen in all cases. Neurological deficits were present in 21 (40%) cases. All patients received radiation in various dosages; 70% additionally received chemotherapy. Twenty-five patients had surgery, and two patients received bone marrow transplantation. Forty-five patients had follow-up; the five-year disease-free survival probability is 0

Improving vertebra segmentation through joint vertebra-rib atlases

Science.gov (United States)

Wang, Yinong; Yao, Jianhua; Roth, Holger R.; Burns, Joseph E.; Summers, Ronald M.

2016-03-01

Accurate spine segmentation allows for improved identification and quantitative characterization of abnormalities of the vertebra, such as vertebral fractures. However, in existing automated vertebra segmentation methods on computed tomography (CT) images, leakage into nearby bones such as ribs occurs due to the close proximity of these visibly intense structures in a 3D CT volume. To reduce this error, we propose the use of joint vertebra-rib atlases to improve the segmentation of vertebrae via multi-atlas joint label fusion. Segmentation was performed and evaluated on CTs containing 106 thoracic and lumbar vertebrae from 10 pathological and traumatic spine patients on an individual vertebra level basis. Vertebra atlases produced errors where the segmentation leaked into the ribs. The use of joint vertebra-rib atlases produced a statistically significant increase in the Dice coefficient from 92.5 +/- 3.1% to 93.8 +/- 2.1% for the left and right transverse processes and a decrease in the mean and max surface distance from 0.75 +/- 0.60mm and 8.63 +/- 4.44mm to 0.30 +/- 0.27mm and 3.65 +/- 2.87mm, respectively.

Estudo experimental do sequenciamento das manobras da ligamentotaxia na descompressão do canal vertebral Experimental study of ligamentotaxis maneuvers sequencing in vertebral canal decompression

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Ilton José Carrilho de Castro

2008-01-01

Full Text Available A descompressão do canal vertebral, para aliviar as estruturas nervosas, pode ser realizada por meio da ligamentotaxia. O objetivo foi analisar a influência da seqüência de realização da ligamentotaxia sobre a descompressão do canal vertebral. Foram utilizados segmentos de vértebras de suínos (Landrace. Um equipamento especialmente desenvolvido foi utilizado para produção de fratura do tipo explosão. Após a tomografia computadorizada, 10 espécimes que melhores apresentavam fraturas do tipo explosão foram fixados com fixador interno (Synthes. Foram formados dois grupos. No primeiro (n=5 foi realizada a lordose e depois a distração. Posteriormente, foram submetidos à nova compressão por meio de morsa até o retorno da fratura à posição inicial, a seguir foram novamente submetidos à distração e lordose. No segundo grupo (n=5 foi realizada a distração e depois a lordose. Após cada manobra era realizado o exame tomográfico para medir o diâmetro do canal vertebral. Os deslocamentos dos fragmentos dos corpos vertebrais fraturados foram mensurados e comparados utilizando t de Student (pVertebral canal decompression, intended to provide relief to nervous structures, may be performed by means of legamentotaxis. The objective of this study was to assess the influence of the ligamentotaxis sequence on vertebral canal decompression. Vertebral segments of Landrace swine specimens were used. A device especially developed for producing a burst-type fracture was employed. Subsequently to the computerized tomography scan, 10 specimens that best showed a burst-type fracture were fixated with internal fixator (Synthes. Two groups were formed. On the first group (n=5, lordosis followed by distraction were performed. Then, they were submitted to distraction and lordosis. On the second group (n=5, distraction was provided first, and then lordosis was performed. After each maneuver, vertebral canal was measured by tomography scan

Transitional lumbosacral vertebral anomaly in the dog: a radiographic study

International Nuclear Information System (INIS)

Morgan, J.P.

1999-01-01

Transitional lumbosacral vertebral anomalies have for some time been suggested as a possible cause of cauda equina syndrome (especially in the German shepherd dog [GSD]), a condition recently thought to be inherited. The frequency of this condition within a large clinical population and the radiographic features used in its detection are reported. In a group of 143 patients, the sexes were similarly represented and the GSD was greatly over represented. The anomaly is characterised by separation of the first sacral segment that was identified on the lateral view by the presence of a radiolucent disc space between what are normally the first and second sacral segments. On the ventrodorsal view, the anomaly was characterised by separation of the spinous processes between what are normally the first and second sacral segments. In the presence of the transitional segment, the nature of the sacroiliac joint at the level of the anomalous segment varies from a strong ilial attachment, with the presence of a wing-like lateral process, to a weakened ilial attachment because of the presence of a lateral process, shaped as that seen on a lumbar segment. These patterns were present unilaterally or bilaterally and result in symmetrical or asymmetrical patterns. The effect of the weakening of the sacroiliac attachment was thought to result in premature disc degeneration, which, together with spinal canal stenosis, resulted in potential compression of the overlying spinal nerves and creation of a cauda equina syndrome. The condition is thought to have clinical significance and should be selected against in breeding, especially in the GSD

Normal reference values for vertebral artery flow volume by color Doppler sonography in Korean adults

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Hong, Hyun Sook; Cha, Jang Gyu; Park, Seong Jin; Joh, Joon Hee; Park, Jai Soung; Kim, Dae Ho; Lee, Hae Kyung; Ahn, Hyun Cheol [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

2003-09-15

Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume. This study was to establish the reference values for the flow volume of the vertebral artery using color Doppler sonography in the normal Korea adults. Thirty five normal Korea adults without any underlying disease including hypertension, hyperlipidemia, diabetes, heart disease, obesity (body mas index>30), or carotid artery stenosis was included. There were 17 males and 18 females, age ranged from 20 to 53 years (average=32.86 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segment, usually at C5-6 level, bilaterally. The flow volume (Q) was calculated. (Q=time averaged mean velocity x cross sectional area of vessel) A lower Flow velocity and smaller vessel diameter were measured on the right side compared to those of the left side, resulting in a lower flow volume. The calculated flow volumes using the equation were 77.0 +- 39.7 ml/min for the right side and 127.6 +- 71.0 ml/min for the left side (p=0.0001) while the net vertebral artery flow volume was 204.6 +- 81.8 ml/min. Decrease in the vertebral artery flow volume was statistically significant with advanced age. (r=-0.36, p=0.032). Vertebral artery blood flow volume was 191.20 +- 59.19 ml/min in male, and 217.28 +- 98.67 ml/min in female (p=0.6). The normal range for the net vertebral artery flow volume defined by the 5th to 95th percentiles was between 110.06 and 364.1 ml/min. The normal range for the net vertebral artery flow volume was between 110.06 and 364.1 ml/min. Vertebral artery flow volume decreased with the increase of age. However, gender did not affect the blood flow volume.

Normal reference values for vertebral artery flow volume by color Doppler sonography in Korean adults

International Nuclear Information System (INIS)

Hong, Hyun Sook; Cha, Jang Gyu; Park, Seong Jin; Joh, Joon Hee; Park, Jai Soung; Kim, Dae Ho; Lee, Hae Kyung; Ahn, Hyun Cheol

2003-01-01

Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume. This study was to establish the reference values for the flow volume of the vertebral artery using color Doppler sonography in the normal Korea adults. Thirty five normal Korea adults without any underlying disease including hypertension, hyperlipidemia, diabetes, heart disease, obesity (body mas index>30), or carotid artery stenosis was included. There were 17 males and 18 females, age ranged from 20 to 53 years (average=32.86 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segment, usually at C5-6 level, bilaterally. The flow volume (Q) was calculated. (Q=time averaged mean velocity x cross sectional area of vessel) A lower Flow velocity and smaller vessel diameter were measured on the right side compared to those of the left side, resulting in a lower flow volume. The calculated flow volumes using the equation were 77.0 ± 39.7 ml/min for the right side and 127.6 ± 71.0 ml/min for the left side (p=0.0001) while the net vertebral artery flow volume was 204.6 ± 81.8 ml/min. Decrease in the vertebral artery flow volume was statistically significant with advanced age. (r=-0.36, p=0.032). Vertebral artery blood flow volume was 191.20 ± 59.19 ml/min in male, and 217.28 ± 98.67 ml/min in female (p=0.6). The normal range for the net vertebral artery flow volume defined by the 5th to 95th percentiles was between 110.06 and 364.1 ml/min. The normal range for the net vertebral artery flow volume was between 110.06 and 364.1 ml/min. Vertebral artery flow volume decreased with the increase of age. However, gender did not affect the blood flow volume.

Delayed vertebral diagnosed L4 pincer vertebral fracture, L2-L3 ruptured vertebral lumbar disc hernia, L5 vertebral wedge fracture - Case report

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Balasa D

2016-08-01

Full Text Available An association between delayed ruptured lumbar disc hernia, L5 vertebral wedge fracture and posttraumaticL4 pincer vertebral fracture (A2.3-AO clasification at different levels is a very rare entity. We present the case of a 55 years old male who falled down from a bicycle. 2 months later because of intense and permanent vertebral lumbar and radicular L2 and L3 pain (Visual Scal Autologus of Pain7-8/10 the patient came to the hospital. He was diagnosed with pincer vertebral L4 fracture (A2.3-AO clasification and L2-L3 right ruptured lumbar disc hernia in lateral reces. The patient was operated (L2-L3 right fenestration, and resection of lumbar disc hernia, bilateral stabilisation, L3-L4-L5 with titan screws and postero-lateral bone graft L4 bilateral harvested from iliac crest.

Interactive-cut: Real-time feedback segmentation for translational research.

Science.gov (United States)

Egger, Jan; Lüddemann, Tobias; Schwarzenberg, Robert; Freisleben, Bernd; Nimsky, Christopher

2014-06-01

In this contribution, a scale-invariant image segmentation algorithm is introduced that "wraps" the algorithm's parameters for the user by its interactive behavior, avoiding the definition of "arbitrary" numbers that the user cannot really understand. Therefore, we designed a specific graph-based segmentation method that only requires a single seed-point inside the target-structure from the user and is thus particularly suitable for immediate processing and interactive, real-time adjustments by the user. In addition, color or gray value information that is needed for the approach can be automatically extracted around the user-defined seed point. Furthermore, the graph is constructed in such a way, so that a polynomial-time mincut computation can provide the segmentation result within a second on an up-to-date computer. The algorithm presented here has been evaluated with fixed seed points on 2D and 3D medical image data, such as brain tumors, cerebral aneurysms and vertebral bodies. Direct comparison of the obtained automatic segmentation results with costlier, manual slice-by-slice segmentations performed by trained physicians, suggest a strong medical relevance of this interactive approach. Copyright © 2014 Elsevier Ltd. All rights reserved.

Surgical-Orthodontic Treatment of Gummy Smile with Vertical Maxillary Excess

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Sumit Kumar Yadav

2014-01-01

Full Text Available Vertical maxillary excess is a well-defined clinical entity with several treatment options available. Treatment of the condition requires extremely well-coordinated orthodontic and surgical treatment planning and execution. This case report describes a multidisciplinary approach in the successful management of a patient with severe vertical maxillary excess. Careful selection and good execution of a surgical-orthodontic treatment plan in the management of vertical maxillary excess provided the superior esthetic and functional results in this case. Maxillary Le Forte 1 procedure was performed for vertical maxillary impaction along with anterior segmental setback. The presented technique was unique as it shortened the treatment time and esthetic results in smile and vertical proportions were achieved.

Imaging the vertebral artery

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Tay, Keng Yeow; U-King-Im, Jean Marie; Trivedi, Rikin A.; Higgins, Nicholas J.; Cross, Justin J.; Antoun, Nagui M. [Addenbrooke' s Hospital and University of Cambridge, Department of Radiology, Cambridge (United Kingdom); Davies, John R.; Weissberg, Peter L. [Addenbrooke' s Hospital and University of Cambridge, Division of Cardiovascular Medicine, Cambridge (United Kingdom); Gillard, Jonathan H. [Addenbrooke' s Hospital and University of Cambridge, Department of Radiology, Cambridge (United Kingdom); Addenbrooke' s Hospitald, University Department of Radiology, Cambridge (United Kingdom)

2005-07-01

Although conventional intraarterial digital subtraction angiography remains the gold standard method for imaging the vertebral artery, noninvasive modalities such as ultrasound, multislice computed tomographic angiography and magnetic resonance angiography are constantly improving and are playing an increasingly important role in diagnosing vertebral artery pathology in clinical practice. This paper reviews the current state of vertebral artery imaging from an evidence-based perspective. Normal anatomy, normal variants and a number of pathological entities such as vertebral atherosclerosis, arterial dissection, arteriovenous fistula, subclavian steal syndrome and vertebrobasilar dolichoectasia are discussed. (orig.)

Imaging the vertebral artery

International Nuclear Information System (INIS)

Tay, Keng Yeow; U-King-Im, Jean Marie; Trivedi, Rikin A.; Higgins, Nicholas J.; Cross, Justin J.; Antoun, Nagui M.; Davies, John R.; Weissberg, Peter L.; Gillard, Jonathan H.

2005-01-01

Although conventional intraarterial digital subtraction angiography remains the gold standard method for imaging the vertebral artery, noninvasive modalities such as ultrasound, multislice computed tomographic angiography and magnetic resonance angiography are constantly improving and are playing an increasingly important role in diagnosing vertebral artery pathology in clinical practice. This paper reviews the current state of vertebral artery imaging from an evidence-based perspective. Normal anatomy, normal variants and a number of pathological entities such as vertebral atherosclerosis, arterial dissection, arteriovenous fistula, subclavian steal syndrome and vertebrobasilar dolichoectasia are discussed. (orig.)

Quantitative dual-energy CT for phantomless evaluation of cancellous bone mineral density of the vertebral pedicle: correlation with pedicle screw pull-out strength

Energy Technology Data Exchange (ETDEWEB)

Wichmann, Julian L.; Booz, Christian; Bauer, Ralf W.; Kerl, J.M.; Fischer, Sebastian; Lehnert, Thomas; Vogl, Thomas J.; Khan, M.F. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Wesarg, Stefan [Fraunhofer IGD, Cognitive Computing and Medical Imaging, Darmstadt (Germany); Kafchitsas, Konstantinos [Spine Center, Asklepios Klinik Lindenlohe, Schwandorf (Germany)

2015-06-01

To evaluate quantitative dual-energy computed tomography (DECT) for phantomless analysis of cancellous bone mineral density (BMD) of vertebral pedicles and to assess the correlation with pedicle screw pull-out strength. Twenty-nine thoracic and lumbar vertebrae from cadaver specimens were examined with DECT. Using dedicated post-processing software, a pedicle screw vector was mapped (R1, intrapedicular segment of the pedicle vector; R2, intermediate segment; R3, intracorporal segment; global, all segments) and BMD was calculated. To invasively evaluate pedicle stability, pedicle screws were drilled through both pedicles and left pedicle screw pull-out strength was measured. Resulting values were correlated using the paired t test and Pearson's linear correlation. Average pedicle screw vector BMD (R1, 0.232 g/cm{sup 3}; R2, 0.166 g/cm{sup 3}; R3, 0.173 g/cm{sup 3}; global, 0.236 g/cm{sup 3}) showed significant differences between R1-R2 (P < 0.002) and R1-R3 (P < 0.034) segments while comparison of R2-R3 did not reach significance (P > 0.668). Average screw pull-out strength (639.2 N) showed a far stronger correlation with R1 (r = 0.80; P < 0.0001) than global BMD (r = 0.42; P = 0.025), R2 (r = 0.37; P = 0.048) and R3 (r = -0.33; P = 0.078) segments. Quantitative DECT allows for phantomless BMD assessment of the vertebral pedicle. BMD of the intrapedicular segment shows a significantly stronger correlation with pedicle screw pull-out strength than other segments. (orig.)

Age distribution of human gene families shows significant roles of both large- and small-scale duplications in vertebrate evolution.

Science.gov (United States)

Gu, Xun; Wang, Yufeng; Gu, Jianying

2002-06-01

The classical (two-round) hypothesis of vertebrate genome duplication proposes two successive whole-genome duplication(s) (polyploidizations) predating the origin of fishes, a view now being seriously challenged. As the debate largely concerns the relative merits of the 'big-bang mode' theory (large-scale duplication) and the 'continuous mode' theory (constant creation by small-scale duplications), we tested whether a significant proportion of paralogous genes in the contemporary human genome was indeed generated in the early stage of vertebrate evolution. After an extensive search of major databases, we dated 1,739 gene duplication events from the phylogenetic analysis of 749 vertebrate gene families. We found a pattern characterized by two waves (I, II) and an ancient component. Wave I represents a recent gene family expansion by tandem or segmental duplications, whereas wave II, a rapid paralogous gene increase in the early stage of vertebrate evolution, supports the idea of genome duplication(s) (the big-bang mode). Further analysis indicated that large- and small-scale gene duplications both make a significant contribution during the early stage of vertebrate evolution to build the current hierarchy of the human proteome.

Management of osteoporotic vertebral fractures

OpenAIRE

Dionyssiotis, Yannis

2010-01-01

Yannis DionyssiotisRhodes General Hospital, Rhodes, GreeceAbstract: Osteoporotic vertebral fractures are associated with considerable reduction of quality of life, morbidity, and mortality. The management of patients with vertebral fractures should include treatment for osteoporosis and measures to reduce pain and improve mobility. This article provides information for management and rehabilitation of vertebral fractures based on clinical experience and literature.Keywords: vertebral fracture...

Pnrc2 regulates 3'UTR-mediated decay of segmentation clock-associated transcripts during zebrafish segmentation.

Science.gov (United States)

Gallagher, Thomas L; Tietz, Kiel T; Morrow, Zachary T; McCammon, Jasmine M; Goldrich, Michael L; Derr, Nicolas L; Amacher, Sharon L

2017-09-01

Vertebrate segmentation is controlled by the segmentation clock, a molecular oscillator that regulates gene expression and cycles rapidly. The expression of many genes oscillates during segmentation, including hairy/Enhancer of split-related (her or Hes) genes, which encode transcriptional repressors that auto-inhibit their own expression, and deltaC (dlc), which encodes a Notch ligand. We previously identified the tortuga (tor) locus in a zebrafish forward genetic screen for genes involved in cyclic transcript regulation and showed that cyclic transcripts accumulate post-splicing in tor mutants. Here we show that cyclic mRNA accumulation in tor mutants is due to loss of pnrc2, which encodes a proline-rich nuclear receptor co-activator implicated in mRNA decay. Using an inducible in vivo reporter system to analyze transcript stability, we find that the her1 3'UTR confers Pnrc2-dependent instability to a heterologous transcript. her1 mRNA decay is Dicer-independent and likely employs a Pnrc2-Upf1-containing mRNA decay complex. Surprisingly, despite accumulation of cyclic transcripts in pnrc2-deficient embryos, we find that cyclic protein is expressed normally. Overall, we show that Pnrc2 promotes 3'UTR-mediated decay of developmentally-regulated segmentation clock transcripts and we uncover an additional post-transcriptional regulatory layer that ensures oscillatory protein expression in the absence of cyclic mRNA decay. Copyright © 2017 Elsevier Inc. All rights reserved.

Anthropometric measurements and vertebral deformities. European Vertebral Osteoporosis Study (EVOS) Group.

Science.gov (United States)

Johnell, O; O'Neill, T; Felsenberg, D; Kanis, J; Cooper, C; Silman, A J

1997-08-15

To investigate the association between anthropometric indices and morphometrically determined vertebral deformity, the authors carried out a cross-sectional study using data from the European Vertebral Osteoporosis Study (EVOS), a population-based study of vertebral osteoporosis in 36 European centers from 19 countries. A total of 16,047 EVOS subjects were included in this analysis, of whom 1,973 subjects (915 males, 1,058 females) (12.3%) aged 50 years or over had one or more vertebral deformities ("cases"). The cases were compared with the 14,074 subjects (6,539 males, 7,535 females) with morphometrically normal spines ("controls"). Data were collected on self-reported height at age 25 years and minimum weight after age 25 years, as well as on current measured height and weight. Body mass index (BMI) and height and weight change were calculated from these data. The relations between these variables and vertebral deformity were examined separately by sex with logistic regression adjusting for age, smoking, and physical activity. In females, there was a significant trend of decreasing risk with increasing quintile of current weight, current BMI, and weight gain since age 25 years. In males, subjects in the lightest quintile for these measures were at increased risk but there was no evidence of a trend. An ecologic analysis by country revealed a negative correlation between mean BMI and the prevalence of deformity in females but not in males. The authors conclude that low body weight is associated with presence of vertebral deformity.

Height gain of vertebral bodies and stabilization of vertebral geometry over one year after vertebroplasty of osteoporotic vertebral fractures

International Nuclear Information System (INIS)

Pitton, Michael B.; Morgen, Nadine; Herber, Sascha; Dueber, Christoph; Drees, Philipp; Boehm, Bertram

2008-01-01

The height gain of vertebral bodies after vertebroplasty and geometrical stability was evaluated over a one-year period. Osteoporotic fractures were treated with vertebroplasty. The vertebral geometry and disc spaces were analysed using reformatted computed tomography (CT) images: heights of the anterior, posterior, and lateral vertebral walls, disc spaces, endplate angles, and minimal endplate distances. Vertebrae were assigned to group I [severe compression (anterior height/posterior height) 0.75). A total of 102 vertebral bodies in 40 patients (12 men, 28 women, age 70.3 ± 9.5) were treated with vertebroplasty and prospectively followed for 12 months. Group I showed a greater benefit compared with group II with respect to anterior height gain (+2.1 ± 1.9 vs +0.7 ± 1.6 mm, P < 0.001), reduction of endplate angle (-3.6 ± 4.2 vs -0.8 ± 2.3 , P < 0.001), and compression index (+0.09 ± 0.11 vs +0.01 ± 0.06, P < 0.001). At one-year follow-up, group I demonstrated preserved anterior height gain (+1.5 ± 2.8 mm, P < 0.015) and improved endplate angle (-3.4 ± 4.9 , P < 0.001). In group II, the vertebral heights returned to and were fixed at the pre-interventional levels. Vertebroplasty provided vertebral height gain over one year, particularly in cases with severe compression. Vertebrae with moderate compression were fixed and stabilized at the pre-treatment level over one year. (orig.)

Evolution of endothelin receptors in vertebrates.

Science.gov (United States)

Braasch, Ingo; Schartl, Manfred

2014-12-01

Endothelin receptors are G protein coupled receptors (GPCRs) of the β-group of rhodopsin receptors that bind to endothelin ligands, which are 21 amino acid long peptides derived from longer prepro-endothelin precursors. The most basal Ednr-like GPCR is found outside vertebrates in the cephalochordate amphioxus, but endothelin ligands are only present among vertebrates, including the lineages of jawless vertebrates (lampreys and hagfishes), cartilaginous vertebrates (sharks, rays, and chimaeras), and bony vertebrates (ray-finned fishes and lobe-finned vertebrates including tetrapods). A bona fide endothelin system is thus a vertebrate-specific innovation with important roles for regulating the cardiovascular system, renal and pulmonary processes, as well as for the development of the vertebrate-specific neural crest cell population and its derivatives. Expectedly, dysregulation of endothelin receptors and the endothelin system leads to a multitude of human diseases. Despite the importance of different types of endothelin receptors for vertebrate development and physiology, current knowledge on endothelin ligand-receptor interactions, on the expression of endothelin receptors and their ligands, and on the functional roles of the endothelin system for embryonic development and in adult vertebrates is very much biased towards amniote vertebrates. Recent analyses from a variety of vertebrate lineages, however, have shown that the endothelin system in lineages such as teleost fish and lampreys is more diverse and is divergent from the mammalian endothelin system. This diversity is mainly based on differential evolution of numerous endothelin system components among vertebrate lineages generated by two rounds of whole genome duplication (three in teleosts) during vertebrate evolution. Here we review current understanding of the evolutionary history of the endothelin receptor family in vertebrates supplemented with surveys on the endothelin receptor gene complement of

Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath.

Science.gov (United States)

Wang, Shou; Kryvi, Harald; Grotmol, Sindre; Wargelius, Anna; Krossøy, Christel; Epple, Mattias; Neues, Frank; Furmanek, Tomasz; Totland, Geir K

2013-08-01

We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. © 2013 Anatomical Society.

New dual-energy X-ray absorptiometry equipment in the assessment of vertebral fractures: technical limits and software accuracy

Energy Technology Data Exchange (ETDEWEB)

Bazzocchi, Alberto; Diano, Danila; Battista, Giuseppe [University of Bologna, Sant' Orsola - Malpighi Hospital, Imaging Division, Clinical Department of Radiological and Histocytopathological Sciences, Bologna (Italy); Albisinni, Ugo [Rizzoli Orthopaedic Institute, Department of Radiology, Bologna (Italy); Rossi, Cristina [University of Parma, Section of Radiological Sciences, Department of Clinic Sciences, Parma (Italy); Guglielmi, Giuseppe [University of Foggia, Department of Radiology, Foggia (Italy); Department of Radiology, Scientific Institute Hospital ' ' Casa Sollievo della Sofferenza' ' , San Giovanni Rotondo (Italy)

2012-07-15

The aim of this study was to investigate software accuracy and influence of body mass index on image quality of Lunar iDXA (Lunar, Madison, WI, USA; software enCORE 12.0) in vertebral fracture (VFs) assessment. We enrolled 65 normal or overweight patients (group 1) and 64 obese patients (group 2) with indication for morphometric evaluation of the spine. Patients underwent iDXA, with scans performed in the standard manner by an expert technologist. Lateral images of the spine were subsequently evaluated by a musculoskeletal radiologist as the gold standard. Our analysis considered five points: vertebral bodies missed or not assessable or wrongly labeled on T4-L4 segment, diagnostic performance of the automatic morphometric point-positioning system in the detection of VFs, upgrading and downgrading of fractures, radiologist intervention rate, and BMI influence. In group 1, 57/845 (6.7%) vertebral bodies and 34/832 (4.1%) in group 2 were not assessable - the upper thoracic spine. enCORE failed to recognize vertebral levels in 5.4% of the patients (7.7% in group 1 vs. 3.1% in group 2). On a lesion-based analysis sensitivity, specificity and accuracy of the software were 81.4, 93.8, and 93.1% in group 1 and 69.1, 88.3, and 86.7% in group 2, respectively. For 52.7% of the vertebrae in group 1 (51/8 upgraded/downgraded) and 70.0% in group 2 (96/26 upgraded/downgraded), a point correction was necessary and this changed the diagnosis respectively in 29.2 and 50.0% of the patients. Differences in diagnostic performance and point correction rate were significantly different between the two groups; however, BMI did not significantly affect vertebral level labeling and was correlated with a better visualization of the whole T4-L4 spine segment. This study provides new and interesting information about the accuracy, reliability, and imaging quality provided by iDXA in the assessment of VFs. (orig.)

Vertebral stabilization using positively threaded profile pins and polymethylmethacrylate, with or without laminectomy, for spinal canal stenosis and vertebral instability caused by congenital thoracic vertebral anomalies.

Science.gov (United States)

Aikawa, Takeshi; Kanazono, Shinichi; Yoshigae, Yuki; Sharp, Nicholas J H; Muñana, Karen R

2007-07-01

To describe diagnostic findings, surgical technique, and outcome in dogs with thoracic spinal canal stenosis and vertebral instability secondary to congenital vertebral anomalies. Retrospective clinical study. Dogs (n=9) with thoracic spinal canal stenosis. Medical records (1995-1996; 2000-2006) of 9 dogs with a myelographic diagnosis of spinal canal stenosis and/or vertebral instability secondary to congenital vertebral anomaly that were surgically managed by vertebral stabilization with or without laminectomy were reviewed. Data on pre- and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes were retrieved. Follow-up evaluations were performed at 1, 2, and 6 months. Long-term outcome was assessed by means of clinical examination or owner telephone interviews. Spinal cord compression was confirmed by myelography, and in 2 dogs, dynamic compression by stress myelography. Eight dogs regained the ability to ambulate postoperatively. One dog with a partial recovery regained voluntary movement but did not become ambulatory. Spinal cord injury secondary to congenital vertebral anomaly may have a good outcome when treated by vertebral stabilization with or without laminectomy. Adequate stabilization of the vertebrae and improved neurologic outcome were achieved in most dogs. Vertebral stabilization using positively threaded profile pins and polymethylmethacrylate with or without laminectomy is an effective treatment for spinal canal stenosis and vertebral instability secondary to congenital thoracic vertebral anomalies.

Extracranial vertebral artery rupture likely secondary to "cupping therapy" superimposed on spontaneous dissection.

Science.gov (United States)

Choi, Jae Young; Huh, Chae Wook; Choi, Chang Hwa; Lee, Jae Il

2016-12-01

The extracranial vertebral artery (VA) is vulnerable to dissection and the V3 segment is the most common location for dissection. Dissection accounts for about 2% of all ischemic strokes and can occur after trauma or chiropractic neck maneuvers. We report an extremely rare case of spontaneous extracranial VA dissection presenting with posterior neck hematoma aggravated after cupping therapy, a treatment in traditional Oriental medicine. We treated the patient successfully by endovascular treatment without any complication. © The Author(s) 2016.

MIA-Clustering: a novel method for segmentation of paleontological material

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Christopher J. Dunmore

2018-02-01

Full Text Available Paleontological research increasingly uses high-resolution micro-computed tomography (μCT to study the inner architecture of modern and fossil bone material to answer important questions regarding vertebrate evolution. This non-destructive method allows for the measurement of otherwise inaccessible morphology. Digital measurement is predicated on the accurate segmentation of modern or fossilized bone from other structures imaged in μCT scans, as errors in segmentation can result in inaccurate calculations of structural parameters. Several approaches to image segmentation have been proposed with varying degrees of automation, ranging from completely manual segmentation, to the selection of input parameters required for computational algorithms. Many of these segmentation algorithms provide speed and reproducibility at the cost of flexibility that manual segmentation provides. In particular, the segmentation of modern and fossil bone in the presence of materials such as desiccated soft tissue, soil matrix or precipitated crystalline material can be difficult. Here we present a free open-source segmentation algorithm application capable of segmenting modern and fossil bone, which also reduces subjective user decisions to a minimum. We compare the effectiveness of this algorithm with another leading method by using both to measure the parameters of a known dimension reference object, as well as to segment an example problematic fossil scan. The results demonstrate that the medical image analysis-clustering method produces accurate segmentations and offers more flexibility than those of equivalent precision. Its free availability, flexibility to deal with non-bone inclusions and limited need for user input give it broad applicability in anthropological, anatomical, and paleontological contexts.

MIA-Clustering: a novel method for segmentation of paleontological material.

Science.gov (United States)

Dunmore, Christopher J; Wollny, Gert; Skinner, Matthew M

2018-01-01

Paleontological research increasingly uses high-resolution micro-computed tomography (μCT) to study the inner architecture of modern and fossil bone material to answer important questions regarding vertebrate evolution. This non-destructive method allows for the measurement of otherwise inaccessible morphology. Digital measurement is predicated on the accurate segmentation of modern or fossilized bone from other structures imaged in μCT scans, as errors in segmentation can result in inaccurate calculations of structural parameters. Several approaches to image segmentation have been proposed with varying degrees of automation, ranging from completely manual segmentation, to the selection of input parameters required for computational algorithms. Many of these segmentation algorithms provide speed and reproducibility at the cost of flexibility that manual segmentation provides. In particular, the segmentation of modern and fossil bone in the presence of materials such as desiccated soft tissue, soil matrix or precipitated crystalline material can be difficult. Here we present a free open-source segmentation algorithm application capable of segmenting modern and fossil bone, which also reduces subjective user decisions to a minimum. We compare the effectiveness of this algorithm with another leading method by using both to measure the parameters of a known dimension reference object, as well as to segment an example problematic fossil scan. The results demonstrate that the medical image analysis-clustering method produces accurate segmentations and offers more flexibility than those of equivalent precision. Its free availability, flexibility to deal with non-bone inclusions and limited need for user input give it broad applicability in anthropological, anatomical, and paleontological contexts.

GPU accelerated fuzzy connected image segmentation by using CUDA.

Science.gov (United States)

Zhuge, Ying; Cao, Yong; Miller, Robert W

2009-01-01

Image segmentation techniques using fuzzy connectedness principles have shown their effectiveness in segmenting a variety of objects in several large applications in recent years. However, one problem of these algorithms has been their excessive computational requirements when processing large image datasets. Nowadays commodity graphics hardware provides high parallel computing power. In this paper, we present a parallel fuzzy connected image segmentation algorithm on Nvidia's Compute Unified Device Architecture (CUDA) platform for segmenting large medical image data sets. Our experiments based on three data sets with small, medium, and large data size demonstrate the efficiency of the parallel algorithm, which achieves a speed-up factor of 7.2x, 7.3x, and 14.4x, correspondingly, for the three data sets over the sequential implementation of fuzzy connected image segmentation algorithm on CPU.

Neurorehabilitation in stroke produced by vertebral artery dissection: case presentation

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Stanescu Ioana

2018-02-01

Full Text Available Arterial dissections are a common cause of stroke in the young (mean age 44 to 46 years. Primary lesion is a tear of the arterial intima, which promotes platelet aggregation, thrombus formation, which further produced vessel stenosis / occlusion, distal embolism or vessel wall rupture. Vertebral artery (VA dissection appear most commonly in extracranial segments V2 and V3, and could be spontaneous (with underlying predispositions or triggered by various traumatisms. Clinicaly, VA dissection produces an ischemic stroke or transient ischemic attack , preceded by local symptoms such as neck pain or headache. The diagnosis is confirmed by neurovascular imaging. Treatment of symptomatic VA dissections respect indications of treatment in ischemic strokes. Prognosis is mostly favorable in extracranial dissections. We present the case of a left VA dissection in V2 segment, produced by physical effort (swimming, which causes 2 ischemic lesions, one in the territory of the left posterior cerebral artery and the other in the territory of the left posterolateral chorroidal artery. Patient’s treatment included antiplatelet agents, statines, and an adapted physical rehabilitation program. At three months he showed significant clinical improvement with regain of autonomy and partial recanalisation at angio-MRI of the V2 segment of the dissected artery.

The shape of the human lumbar vertebral canal A forma do canal vertebral lombar humano

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Edmundo Zarzur

1996-09-01

Full Text Available Literature on the anatomy of the human vertebral column characterizes the shape of the lumbar vertebral canal as triangular. The purpose of the present study was to determine the precise shape of the lumbar vertebral canal. Ten lumbar vertebral columns of adult male cadavers were dissected. Two transverse sections were performed in the third lumbar vertebra. One section was performed at the level of the lower border of the ligamenta flava, and the other section was performed at the level of the pedicles. The shape of the lumbar vertebral canal at the level of the pedicles tends to be oval or circular, whereas the shape of the lumbar vertebral canal at the level of the lower border of the ligamenta flava is triangular. Thus, the shape of the human lumbar vertebral canal is not exclusively triangular, as reported in the literature. It is related to the level of the transversal section performed on the lumbar vertebra. This finding should be taken into consideration among factors involved in the spread of solutions introduced into the epidural space.A literatura sobre a anatomia da coluna vertebral descreve como sendo triangular o formato do canal vertebral na região lombar. O objetivo deste estudo é determinar a real forma do canal da coluna vertebral lombar.Dez colunas vertebrais de cadáveres de homens adultos foram dissecadas. Dois cortes transversais foram executados na terceira vértebra lombar. Um corte foi feito no nível das bordas inferiores de dois ligamentos amarelos vizinhos e o outro corte foi transversal, no nível dos pedículos. A forma do canal vertebral variou: no nível dos pedículos ela tende a ser oval ou circular e junto às bordas inferiores dos ligamentos amarelos passa a ser triangular. Portanto, a forma do canal vertebral lombar não é somente triangular; ela depende do nível em que se faz o corte transversal da vértebra. Estes achados devem ser levados em consideração entre os fatores envolvidos na difusão das

Loss of col8a1a Function during Zebrafish Embryogenesis Results in Congenital Vertebral Malformations

Science.gov (United States)

Gray, Ryan S.; Wilm, Thomas; Smith, Jeff; Bagnat, Michel; Dale, Rodney M.; Topczewski, Jacek; Johnson, Stephen L.; Solnica-Krezel, Lilianna

2014-01-01

Congenital vertebral malformations (CVM) occur in 1 in 1,000 live births and in many cases can cause spinal deformities, such as scoliosis, and result in disability and distress of affected individuals. Many severe forms of the disease, such as spondylocostal dystostosis, are recessive monogenic traits affecting somitogenesis, however the etiologies of the majority of CVM cases remain undetermined. Here we demonstrate that morphological defects of the notochord in zebrafish can generate congenital-type spine defects. We characterize three recessive zebrafish leviathan/col8a1a mutant alleles (m531, vu41, vu105) that disrupt collagen type VIII alpha1a (col8a1a), and cause folding of the embryonic notochord and consequently adult vertebral column malformations. Furthermore, we provide evidence that a transient loss of col8a1a function or inhibition of Lysyl oxidases with drugs during embryogenesis was sufficient to generate vertebral fusions and scoliosis in the adult spine. Using periodic imaging of individual zebrafish, we correlate focal notochord defects of the embryo with vertebral malformations (VM) in the adult. Finally, we show that bends and kinks in the notochord can lead to aberrant apposition of osteoblasts normally confined to well-segmented areas of the developing vertebral bodies. Our results afford a novel mechanism for the formation of VM, independent of defects of somitogenesis, resulting from aberrant bone deposition at regions of misshapen notochord tissue. PMID:24333517

Vertebral Compression Fracture in a Patient with Hyperthyroidism

Directory of Open Access Journals (Sweden)

Ayhan Kul

2016-12-01

Full Text Available Osteoporosis in men is an important public health problem, and its prevalence is increasing as the population ages. Although it is traditionally considered as a women’s health issue, osteoporosis-related mortality and morbidity rates are higher in men. Although the lifetime risk of the hip fracture is lower in men than women, men are twice as likely to die after a hip fracture. All men diagnosed with osteoporosis should be evaluated for secondary causes of bone loss, such as hypogonadism, the use of corticosteroid, smoking, excessive alcohol consumption, low calcium intake, vitamin D deficiency and hypothyroidism. Here, we aimed to present a male patient in whom osteoporotic a vertebral fracture was detected and who was diagnosed with hyperthyroidism.

Primary extracranial vertebral artery aneurysms.

Science.gov (United States)

Morasch, Mark D; Phade, Sachin V; Naughton, Peter; Garcia-Toca, Manuel; Escobar, Guillermo; Berguer, Ramon

2013-05-01

Extracranial vertebral artery aneurysms are uncommon and are usually associated with trauma or dissection. Primary cervical vertebral aneurysms are even rarer and are not well described. The presentation and natural history are unknown and operative management can be difficult. Accessing aneurysms at the skull base can be difficult and, because the frail arteries are often afflicted with connective tissue abnormalities, direct repair can be particularly challenging. We describe the presentation and surgical management of patients with primary extracranial vertebral artery aneurysms. In this study we performed a retrospective, multi-institutional review of patients with primary aneurysms within the extracranial vertebral artery. Between January 2000 and January 2011, 7 patients, aged 12-56 years, were noted to have 9 primary extracranial vertebral artery aneurysms. All had underlying connective tissue or another hereditary disorder, including Ehler-Danlos syndrome (n=3), Marfan's disease (n=2), neurofibromatosis (n=1), and an unspecified connective tissue abnormality (n=1). Eight of 9 aneurysms were managed operatively, including an attempted bypass that ultimately required vertebral ligation; the contralateral aneurysm on this patient has not been treated. Open interventions included vertebral bypass with vein, external carotid autograft, and vertebral transposition to the internal carotid artery. Special techniques were used for handling the anastomoses in patients with Ehler-Danlos syndrome. Although endovascular exclusion was not performed in isolation, 2 hybrid procedures were performed. There were no instances of perioperative stroke or death. Primary extracranial vertebral artery aneurysms are rare and occur in patients with hereditary disorders. Operative intervention is warranted in symptomatic patients. Exclusion and reconstruction may be performed with open and hybrid techniques with low morbidity and mortality. Copyright © 2013 Elsevier Inc. All rights

Measurements of vertebral shape by radiographic morphometry: sex differences and relationships with vertebral level and lumbar lordosis

Energy Technology Data Exchange (ETDEWEB)

Cheng, X G; Sun, Y; Boonen, S; Nicholson, P H.F.; Dequeker, J [Arthritis and Metabolic Bone Disease Research Unit, U.Z. Pellenberg, Division of Rheumatology, Pellenberg (Belgium); Brys, P [Radiology Department, University Hospitals, Katholieke Universiteit Leuven, Leuven (Belgium); Felsenberg, D [Radiology Department, Freie Univ. Berlin (Germany)

1998-07-01

Objective. To examine sex-related and vertebral-level-specific differences in vertebral shape and to investigate the relationships between the lumbar lordosis angle and vertebral morphology. Design and patients. Lateral thoracic and lumbar spine radiographs were obtained with a standardized protocol in 142 healthy men and 198 healthy women over 50 years old. Anterior (Ha), central (Hc) and posterior (Hp) heights of each vertebra from T4 to L4 were measured using a digitizing technique, and the Ha/Hp and Hc/Hp ratios were calculated. The lumbar lordosis angle was measured on the lateral lumbar spine radiographs. Results. Ha/Hp and Hc/Hp ratios were smaller in men than women by 1.8% and 0.7%, respectively, and these ratios varied with vertebral level. Significant correlations were found between vertebral shape and the lumbar lordosis angle. Conclusions. These results demonstrate that vertebral shape varies significantly with sex, vertebral level and lumbar lordosis angle. Awareness of these relationships may help prevent misdiagnosis in clinical vertebral morphometry. (orig.) With 4 figs., 2 tabs., 17 refs.

V-SINEs: A New Superfamily of Vertebrate SINEs That Are Widespread in Vertebrate Genomes and Retain a Strongly Conserved Segment within Each Repetitive Unit

Science.gov (United States)

Ogiwara, Ikuo; Miya, Masaki; Ohshima, Kazuhiko; Okada, Norihiro

2002-01-01

We have identified a new superfamily of vertebrate short interspersed repetitive elements (SINEs), designated V-SINEs, that are widespread in fishes and frogs. Each V-SINE includes a central conserved domain preceded by a 5′-end tRNA-related region and followed by a potentially recombinogenic (TG)n tract, with a 3′ tail derived from the 3′ untranslated region (UTR) of the corresponding partner long interspersed repetitive element (LINE) that encodes a functional reverse transcriptase. The central domain is strongly conserved and is even found in SINEs in the lamprey genome, suggesting that V-SINEs might be ∼550 Myr old or older in view of the timing of divergence of the lamprey lineage from the bony fish lineage. The central conserved domain might have been subject to some form of positive selection. Although the contemporary 3′ tails of V-SINEs differ from one another, it is possible that the original 3′ tail might have been replaced, via recombination, by the 3′ tails of more active partner LINEs, thereby retaining retropositional activity and the ability to survive for long periods on the evolutionary time scale. It seems plausible that V-SINEs may have some function(s) that have been maintained by the coevolution of SINEs and LINEs during the evolution of vertebrates. [The sequences reported in this paper have been deposited in the DDBJ/GenBank database under accession nos. AB072981–AB073004. Supplemental figures are available online at http://www.genome.org.] PMID:11827951

Constrained vertebrate evolution by pleiotropic genes

DEFF Research Database (Denmark)

Hu, Haiyang; Uesaka, Masahiro; Guo, Song

2017-01-01

applied to vertebrates than chordates. Furthermore, we found that vertebrates' conserved mid-embryonic developmental programmes are intensively recruited to other developmental processes, and the degree of the recruitment positively correlates with their evolutionary conservation and essentiality...... for normal development. Thus, we propose that the intensively recruited genetic system during vertebrates' organogenesis period imposed constraints on its diversification through pleiotropic constraints, which ultimately led to the common anatomical pattern observed in vertebrates....

Gene order data from a model amphibian (Ambystoma: new perspectives on vertebrate genome structure and evolution

Directory of Open Access Journals (Sweden)

Voss S Randal

2006-08-01

Full Text Available Abstract Background Because amphibians arise from a branch of the vertebrate evolutionary tree that is juxtaposed between fishes and amniotes, they provide important comparative perspective for reconstructing character changes that have occurred during vertebrate evolution. Here, we report the first comparative study of vertebrate genome structure that includes a representative amphibian. We used 491 transcribed sequences from a salamander (Ambystoma genetic map and whole genome assemblies for human, mouse, rat, dog, chicken, zebrafish, and the freshwater pufferfish Tetraodon nigroviridis to compare gene orders and rearrangement rates. Results Ambystoma has experienced a rate of genome rearrangement that is substantially lower than mammalian species but similar to that of chicken and fish. Overall, we found greater conservation of genome structure between Ambystoma and tetrapod vertebrates, nevertheless, 57% of Ambystoma-fish orthologs are found in conserved syntenies of four or more genes. Comparisons between Ambystoma and amniotes reveal extensive conservation of segmental homology for 57% of the presumptive Ambystoma-amniote orthologs. Conclusion Our analyses suggest relatively constant interchromosomal rearrangement rates from the euteleost ancestor to the origin of mammals and illustrate the utility of amphibian mapping data in establishing ancestral amniote and tetrapod gene orders. Comparisons between Ambystoma and amniotes reveal some of the key events that have structured the human genome since diversification of the ancestral amniote lineage.

[Stability of ventral, dorsal and combined spondylodesis in vertebral body prosthesis implantation].

Science.gov (United States)

Vahldiek, M; Gossè, F; Panjabi, M M

2002-05-01

The purpose of this study was to evaluate the biomechanical characteristics of short-segment anterior, posterior, and combined instrumentations in lumbar spine vertebral body replacement surgery. Eight fresh frozen human cadaveric thoracolumbar spine specimens (T12-L4) were prepared for biomechanical testing. Pure moments (2.5, 5, and 7.5 Nm) of flexion-extension, left-right axial torsion, and left-right lateral bending were applied to the top vertebra in a flexibility machine and the motions of L1 vertebra with respect to L3 were recorded with an optoelectronic motion measurement system after preconditioning. One anterior, two posterior pedicle screw systems, and two combined instrumentations were tested. Load-displacement curves were recorded and neutral zone (NZ) and range of motion (ROM) were determined. The anterior instrumentation, after vertebral body replacement, showed greater motion than the intact spine, especially in axial torsion. Posterior instrumentation provided greater rigidity than the anterior instrumentation, especially in flexion-extension. The combined instrumentation provided superior rigidity in all directions compared to all other instrumentations.

Real-time tracking of vertebral body movement with implantable reference microsensors.

Science.gov (United States)

Mularski, Sven; Picht, Thomas; Kuehn, Björn; Kombos, Theodoros; Brock, Mario; Suess, Olaf

2006-05-01

In the spine, navigation techniques serve mainly to control and accurately target insertion of implants. The main source of error is that the spine is not a rigid organ, but rather a chain of semiflexible movement segments. Any intraoperative manipulation of the patient alters the geometry and volumetry as compared to the 3D volume model created from the image data. Thus, the objective of the study was to implement the theoretical principle of microsensor referencing in a model experiment and to clarify which anatomical structures are suitable for intermittent implantation of positional sensors, as illustrated with cervical vertebral bodies. Laboratory tests were conducted using 70 models of human cervical vertebral bodies. The first experiment investigated whether arbitrary movements of vertebral bodies can be tracked with the positional information from the implanted microsensors. The accuracy of this movement monitoring was determined quantitatively on the basis of positional error measurement. In the second experiment, different ventral and dorsal surgical operations were simulated on five models of the cervical spine. Quantifiable measurement values such as the spatial extension of the intervertebral space and the relative positions of the planes of the upper plates were determined. With respect to the differing anatomy of the individual vertebral bodies of the cervical spine, the sensors could be placed securely with a 5x2 mm drill. The registration error (RE) was determined as a root mean square error. The mean value was 0.9425 mm (range: 0.57-1.2 mm; median: 0.9400 mm; SD: 0.1903 mm). The precision of the movement monitoring of the vertebral body was investigated along its three main axes. The error tolerance between post-interventional 3D reconstruction and direct measurement on the model did not exceed 1.3 mm in the distance measurements or 2.5 degrees in the angular measurements. The tomograms on the system monitor could be updated in close to real time

Rapid onset aggressive vertebral haemangioma.

Science.gov (United States)

Cheung, Nicholas K; Doorenbosch, Xenia; Christie, John G

2011-03-01

Vertebral haemangiomas are generally benign asymptomatic vascular tumours seen commonly in the adult population. Presentations in paediatric populations are extremely rare, which can result in rapid onset of neurological symptoms. We present a highly unusual case of an aggressive paediatric vertebral haemangioma causing significant cord compression. A 13-year-old boy presented with only 2 weeks duration of progressive gait disturbance, truncal ataxia and loss of bladder control. Magnetic resonance imaging (MRI) of the spine revealed a large vascular epidural mass extending between T6 and T8 vertebral bodies. Associated displacement and compression of the spinal cord was present. A highly vascular bony lesion was found during surgery. Histopathology identified this tumour to be a vertebral haemangioma. We present an extremely unusual acute presentation of a paediatric vertebral haemangioma. This study highlights the need for early diagnosis, MRI for investigation and urgent surgical management. © Springer-Verlag 2011

Detection and correction of false segmental duplications caused by genome mis-assembly

Science.gov (United States)

2010-01-01

Diploid genomes with divergent chromosomes present special problems for assembly software as two copies of especially polymorphic regions may be mistakenly constructed, creating the appearance of a recent segmental duplication. We developed a method for identifying such false duplications and applied it to four vertebrate genomes. For each genome, we corrected mis-assemblies, improved estimates of the amount of duplicated sequence, and recovered polymorphisms between the sequenced chromosomes. PMID:20219098

Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fractures: Analysis of Risk Factors.

Science.gov (United States)

Xie, Weixing; Jin, Daxiang; Ma, Hui; Ding, Jinyong; Xu, Jixi; Zhang, Shuncong; Liang, De

2016-05-01

The risk factors for cement leakage were retrospectively reviewed in 192 patients who underwent percutaneous vertebral augmentation (PVA). To discuss the factors related to the cement leakage in PVA procedure for the treatment of osteoporotic vertebral compression fractures. PVA is widely applied for the treatment of osteoporotic vertebral fractures. Cement leakage is a major complication of this procedure. The risk factors for cement leakage were controversial. A retrospective review of 192 patients who underwent PVA was conducted. The following data were recorded: age, sex, bone density, number of fractured vertebrae before surgery, number of treated vertebrae, severity of the treated vertebrae, operative approach, volume of injected bone cement, preoperative vertebral compression ratio, preoperative local kyphosis angle, intraosseous clefts, preoperative vertebral cortical bone defect, and ratio and type of cement leakage. To study the correlation between each factor and cement leakage ratio, bivariate regression analysis was employed to perform univariate analysis, whereas multivariate linear regression analysis was employed to perform multivariate analysis. The study included 192 patients (282 treated vertebrae), and cement leakage occurred in 100 vertebrae (35.46%). The vertebrae with preoperative cortical bone defects generally exhibited higher cement leakage ratio, and the leakage is typically type C. Vertebrae with intact cortical bones before the procedure tend to experience type S leakage. Univariate analysis showed that patient age, bone density, number of fractured vertebrae before surgery, and vertebral cortical bone were associated with cement leakage ratio (Pcement leakage are bone density and vertebral cortical bone defect, with standardized partial regression coefficients of -0.085 and 0.144, respectively. High bone density and vertebral cortical bone defect are independent risk factors associated with bone cement leakage.

Measurements of vertebral shape by r[iographic morphometry: sex differences and relationships with vertebral level and lumbar lordosis

International Nuclear Information System (INIS)

Cheng, X.G.; Sun, Y.; Boonen, S.; Nicholson, P.H.F.; Dequeker, J.; Brys, P.; Felsenberg, D.

1998-01-01

Objective. To examine sex-related and vertebral-level-specific differences in vertebral shape and to investigate the relationships between the lumbar lordosis angle and vertebral morphology. Design and patients. Lateral thoracic and lumbar spine r[iographs were obtained with a standardized protocol in 142 healthy men and 198 healthy women over 50 years old. Anterior (Ha), central (Hc) and posterior (Hp) heights of each vertebra from T4 to L4 were measured using a digitizing technique, and the Ha/Hp and Hc/Hp ratios were calculated. The lumbar lordosis angle was measured on the lateral lumbar spine r[iographs. Results. Ha/Hp and Hc/Hp ratios were smaller in men than women by 1.8% and 0.7%, respectively, and these ratios varied with vertebral level. Significant correlations were found between vertebral shape and the lumbar lordosis angle. Conclusions. These results demonstrate that vertebral shape varies significantly with sex, vertebral level and lumbar lordosis angle. Awareness of these relationships may help prevent misdiagnosis in clinical vertebral morphometry. (orig.)

Pleural effusion segmentation in thin-slice CT

Science.gov (United States)

Donohue, Rory; Shearer, Andrew; Bruzzi, John; Khosa, Huma

2009-02-01

A pleural effusion is excess fluid that collects in the pleural cavity, the fluid-filled space that surrounds the lungs. Surplus amounts of such fluid can impair breathing by limiting the expansion of the lungs during inhalation. Measuring the fluid volume is indicative of the effectiveness of any treatment but, due to the similarity to surround regions, fragments of collapsed lung present and topological changes; accurate quantification of the effusion volume is a difficult imaging problem. A novel code is presented which performs conditional region growth to accurately segment the effusion shape across a dataset. We demonstrate the applicability of our technique in the segmentation of pleural effusion and pulmonary masses.

[Vertebrate mortality in the Guanare-Guanarito road, Portuguesa state, Venezuela].

Science.gov (United States)

Seijas, Andrés Eloy; Araujo-Quintero, Alexis; Velásquez, Nadines

2013-12-01

Roads directly or indirectly affect the structure, dynamics and function of ecosystems that they traverse. Most studies on the effect of roads on wildlife focus on the evaluation of mortality of vertebrates by vehicle collisions. Despite the extensive road network that exists in Venezuela, studies of wildlife mortality in them are scarce. In this paper, we analyzed the temporal and spatial pattern of vertebrate's collisions along the road Guanare-Guanarito, in Portuguesa state. We travelled 26 times between these towns (74 km) to localize dead vertebrates, at a speed of 50-60km/h. of those trips were conducted from March 13 to October 26, 2010, and 10 additional trips from December 7, 2009 to December 14, 2010; these ones, with the aim to include months and seasons that were insufficiently sampled during the first period. The elapsed time between trips varied from 14 to 37 days. The total distance traveled was 1 924 km. Dead animals found amounted 464 individuals, 66 of them were birds (25 identified species), 130 mammals (15 species) and 268 reptiles (18 species). The species with the highest number of individuals were the snake Leptodeira annulata (n=119), the oppossum Didelphis marsupialis (n=39) and the spectacled caiman Caiman crocodilus (n=33). Excluding domestic animals, the rate of road-killed vertebrates was 0.2282 indiv./km, a figure 28.3% higher than previous studies in the same road. Changes in the relative number of collisions for some species, respect to the numbers reported 20 years ago, were linked to the increase in traffic flow and changes in land use. Road segments with collision rates higher than expected by chance were identified. Collition by cars may be the principal cause of mortality for species like the tamandua (Tamandua tetradactyla) and the giant anteater (Myrmecophaga tridactyla), the last considered a vulnerable species. Some basic measures are proposed to reduce wildlife mortality on the road.

Evaluation of the carotid and vertebral arteries: comparison of 3D SCTA and IA-DSA-work in progress

International Nuclear Information System (INIS)

Seemann, M.D.; Minx, C.; Heuck, A.; Reiser, M.F.; Englmeier, K.H.; Schuhmann, D.R.G.; Fuerst, H.

1999-01-01

Objective: The purpose of this study was to develop a method for three-dimensional (3D) visualization of the whole vascular system of the carotid and vertebral arteries using spiral computed tomographic angiography (SCTA), that allows accurate, qualitative and quantitative evaluation, of anatomical abnormalities, including detection of additional lesions, and estimation of degree of stenosis. Materials and methods: Fifteen patients with anatomical and pathological abnormalities of the arterial vascular system detected by color-coded duplex ultrasound were studied using intraarterial digital subtraction angiography (IA-DSA) with aortic arch injection, and SCTA. The carotid and vertebral arteries were segmented using an interactive threshold interval density volume-growing method and visualized with a color-coded shaded-surface display (SSD) rendering method. The adjacent bone structures were visualized using a transparent volume rendering method. Results: In all cases, the entire volume of the vascular system of the carotid and vertebral arteries could be visualized on SCTA, and the anatomical and pathological abnormalities on 3D SCTA correlated well with that seen on IA-DSA. Conclusion: Results of 3D SCTA had a high degree of correlation with results of IA-DSA in the evaluation of the vascular system of the carotid and vertebral arteries. The 3D SCTA with a subsecond spiral CT scanner is useful for the visualization of anatomical and pathological abnormalities in the circulation in the carotid and vertebral arteries and offer a promising minimally invasive alternative compared with other diagnostic procedures. (orig.) (orig.)

Evaluation on vertebral endplate injury and adjacent intervertebral disk injury of patients with osteoporotic vertebral compression fractures by MRI and its clinical significance

International Nuclear Information System (INIS)

Shen Yu; Shen Huiliang; Fang Xiutong; Zhang Wenbo

2012-01-01

Objective: To investigate the relationship between vertebral endplate injury and adjacent intervertebral disk injury of patients with acute or sub-acute osteoporotic vertebral compression fractures (OVC-F) by MRI, and to provide basis for diagnosis of OVCF. Methods: The clinical data of a total of 66 patients with OVCF underwent vertebroplasty (76 fracture of vertebral bodies) were selected. The vertebral endplate injury and adjacent intervertebral disk injury of OVCF patients were detected by MRI. Results: There were 57 vertebral endplate injury in 76 fracture vertebral bodies (75% ). There were only 27 vertebral bodies with vertebral endplate injury in 57 fracture vertebral bodies with endplate injury (47% ), and 22 vertebral with superior and inferior vertebral endplate injury (39% ), and 8 vertebral bodies with inferior vertebral endplate injury (14% ). There were 48 vertebral bodies with intervertebral disc injury in 76 fracture vertebral bodies (63% ). There were 22 intervertebral disc injury located above the fracture of the lumbar spine in 48 vertebral bodies with intervertebral disc injury (45% ), and 19 fracture vertebral bodies with upper and lower intervertebral disc injury (40% ), and 7 intervertebral injuries located below the fracture of the lumbar spine (15% ). Conclusion: Vertebral endplate injury is frequently associated with the adjacent intervertebral disk injury. The clinical diagnosis and treatment should be emphasized in the fracture vertebral endplate damage and adjacent intervertebral disc injury. (authors)

Extension of the segment-based Wilson and NRTL models for correlation of excess molar enthalpies of polymer solutions

International Nuclear Information System (INIS)

Sadeghi, Rahmat

2005-01-01

The polymer Wilson model and the polymer NRTL model have been extended for the representation of the excess enthalpy of multicomponent polymer solutions. Applicability of obtained equations in the correlation of the excess enthalpies of polymer solutions has been examined. It is found that the both models are suitable models in representing the published excess enthalpy data for the tested polymer solutions

The lamprey: a jawless vertebrate model system for examining origin of the neural crest and other vertebrate traits.

Science.gov (United States)

Green, Stephen A; Bronner, Marianne E

2014-01-01

Lampreys are a group of jawless fishes that serve as an important point of comparison for studies of vertebrate evolution. Lampreys and hagfishes are agnathan fishes, the cyclostomes, which sit at a crucial phylogenetic position as the only living sister group of the jawed vertebrates. Comparisons between cyclostomes and jawed vertebrates can help identify shared derived (i.e. synapomorphic) traits that might have been inherited from ancestral early vertebrates, if unlikely to have arisen convergently by chance. One example of a uniquely vertebrate trait is the neural crest, an embryonic tissue that produces many cell types crucial to vertebrate features, such as the craniofacial skeleton, pigmentation of the skin, and much of the peripheral nervous system (Gans and Northcutt, 1983). Invertebrate chordates arguably lack unambiguous neural crest homologs, yet have cells with some similarities, making comparisons with lampreys and jawed vertebrates essential for inferring characteristics of development in early vertebrates, and how they may have evolved from nonvertebrate chordates. Here we review recent research on cyclostome neural crest development, including research on lamprey gene regulatory networks and differentiated neural crest fates. Copyright © 2014 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

Repeated vertebral augmentation for new vertebral compression fractures of postvertebral augmentation patients: a nationwide cohort study

Directory of Open Access Journals (Sweden)

Liang CL

2015-03-01

Full Text Available Cheng-Loong Liang,1 Hao-Kwan Wang,1 Fei-Kai Syu,2 Kuo-Wei Wang,1 Kang Lu,1 Po-Chou Liliang1 1Department of Neurosurgery, E-Da Hospital, I-Shou University, Kaohsiung City, Taiwan; 2Department of Pharmacy, China Medical University Hospital, Taichung City, Taiwan Purpose: Postvertebral augmentation vertebral compression fractures are common; repeated vertebral augmentation is usually performed for prompt pain relief. This study aimed to evaluate the incidence and risk factors of repeat vertebral augmentation.Methods: We performed a retrospective, nationwide, population-based longitudinal observation study, using the National Health Insurance Research Database (NHIRD of Taiwan. All patients who received vertebral augmentation for vertebral compression fractures were evaluated. The collected data included patient characteristics (demographics, comorbidities, and medication exposure and repeat vertebral augmentation. Kaplan–Meier and stratified Cox proportional hazard regressions were performed for analyses.Results: The overall incidence of repeat vertebral augmentation was 11.3% during the follow-up until 2010. Patients with the following characteristics were at greater risk for repeat vertebral augmentation: female sex (AOR=1.24; 95% confidence interval [CI]: 1.10–2.36, advanced age (AOR=1.60; 95% CI: 1.32–2.08, diabetes mellitus (AOR=4.31; 95% CI: 4.05–5.88, cerebrovascular disease (AOR=4.09; 95% CI: 3.44–5.76, dementia (AOR=1.97; 95% CI: 1.69–2.33, blindness or low vision (AOR=3.72; 95% CI: 2.32–3.95, hypertension (AOR=2.58; 95% CI: 2.35–3.47, and hyperlipidemia (AOR=2.09; 95% CI: 1.67–2.22. Patients taking calcium/ vitamin D (AOR=2.98; 95% CI: 1.83–3.93, bisphosphonates (AOR=2.11; 95% CI: 1.26–2.61, or calcitonin (AOR=4.59; 95% CI: 3.40–5.77 were less likely to undergo repeat vertebral augmentation; however, those taking steroids (AOR=7.28; 95% CI: 6.32–8.08, acetaminophen (AOR=3.54; 95% CI: 2.75–4.83, or nonsteroidal

Diagnosis of vertebral fractures on lateral chest X-ray: Intraobserver agreement of semi-quantitative vertebral fracture assessment

International Nuclear Information System (INIS)

Jagt-Willems, H.C. van der; Munster, B.C. van; Leeflang, M.; Beuerle, E.; Tulner, C.R.; Lems, W.F.

2014-01-01

Highlights: • (Lateral) chest X-ray's are often performed in older individuals for various reasons. • Vertebral fractures are visualized on lateral chest X-ray, but the diagnosis of vertebral fractures is until now only validated on (lateral) spine X-ray's. • This study shows that a (lateral) chest X-ray is sufficient for the diagnosis of vertebral fractures. • Older individuals with a vertebral fracture on a (lateral) chest X-ray do not need further radiography with thoracic spine X-ray or vertebral fracture assessment with DXA. - Abstract: Background: In clinical practice lateral images of the chest are performed for various reasons. As these lateral chest X rays show the vertebrae of the thoracic and thoraco-lumbar region, we wondered if these X-rays can be used for evaluation of vertebral fractures instead of separate thoracic spine X-rays. Methods: To evaluate the agreement and intraobserver reliability of the semi-quantitative method for vertebral fractures on the lateral chest X-ray (X-chest) in comparison to the lateral thoracic spine X-ray (X-Tspine), two observers scored vertebral fractures on X-Tspine and twice on X-chest, separately, blinded and in different time periods. Agreement and Cohens’ kappa were calculated for a diagnosis of any fracture on patient level and on vertebral body level. The study was done in patients visiting an outpatient geriatric day clinic, with a high prevalence of vertebral fractures. Results: 109 patients were included. The intraobserver agreement for X-chest versus X-Tspine was 95–98% for the two levels of fracturing, with a Cohen's kappa of 0.88–0.91. The intraobserver agreement and reliability of the re-test on the X-chest showed an agreement between 91 and 98% with a Cohen's kappa of 0.81–0.93. More vertebrae were visible on the X-chest, mean 10.2, SD 0.66 versus mean 9.8, SD 0.73 on the X-Tspine (p < 0.001). Conclusion: The results show good agreement and intraobserver reliability on

Diagnosis of vertebral fractures on lateral chest X-ray: Intraobserver agreement of semi-quantitative vertebral fracture assessment

Energy Technology Data Exchange (ETDEWEB)

Jagt-Willems, H.C. van der, E-mail: Hvanderjagt@spaarneziekenhuis.nl [Department of Geriatrics, Slotervaart Hospital, Amsterdam (Netherlands); Department of Internal Medicine, Spaarne Hospital, Hoofddorp (Netherlands); Munster, B.C. van [Department of Internal Medicine, Academic Medical Center, Amsterdam (Netherlands); Department of Geriatrics, Gelre Hospitals, Apeldoorn (Netherlands); Leeflang, M. [Department of Geriatrics, Gelre Hospitals, Apeldoorn (Netherlands); Beuerle, E. [Department of Radiology, Slotervaart Hospital, Amsterdam (Netherlands); Tulner, C.R. [Department of Geriatrics, Slotervaart Hospital, Amsterdam (Netherlands); Lems, W.F. [Department of Rheumatology, VU Medical Center, Amsterdam (Netherlands)

2014-12-15

Highlights: • (Lateral) chest X-ray's are often performed in older individuals for various reasons. • Vertebral fractures are visualized on lateral chest X-ray, but the diagnosis of vertebral fractures is until now only validated on (lateral) spine X-ray's. • This study shows that a (lateral) chest X-ray is sufficient for the diagnosis of vertebral fractures. • Older individuals with a vertebral fracture on a (lateral) chest X-ray do not need further radiography with thoracic spine X-ray or vertebral fracture assessment with DXA. - Abstract: Background: In clinical practice lateral images of the chest are performed for various reasons. As these lateral chest X rays show the vertebrae of the thoracic and thoraco-lumbar region, we wondered if these X-rays can be used for evaluation of vertebral fractures instead of separate thoracic spine X-rays. Methods: To evaluate the agreement and intraobserver reliability of the semi-quantitative method for vertebral fractures on the lateral chest X-ray (X-chest) in comparison to the lateral thoracic spine X-ray (X-Tspine), two observers scored vertebral fractures on X-Tspine and twice on X-chest, separately, blinded and in different time periods. Agreement and Cohens’ kappa were calculated for a diagnosis of any fracture on patient level and on vertebral body level. The study was done in patients visiting an outpatient geriatric day clinic, with a high prevalence of vertebral fractures. Results: 109 patients were included. The intraobserver agreement for X-chest versus X-Tspine was 95–98% for the two levels of fracturing, with a Cohen's kappa of 0.88–0.91. The intraobserver agreement and reliability of the re-test on the X-chest showed an agreement between 91 and 98% with a Cohen's kappa of 0.81–0.93. More vertebrae were visible on the X-chest, mean 10.2, SD 0.66 versus mean 9.8, SD 0.73 on the X-Tspine (p < 0.001). Conclusion: The results show good agreement and intraobserver reliability on

Imaging assessment of vertebral burst fracture

International Nuclear Information System (INIS)

Ding Jianlin; Liang Lihua; Wang Yujia

2006-01-01

Objective: To investigate the diagnostic value of radiography, CT and MRI in diagnosis of vertebral burst fracture. Methods: 51 patients with vertebral burst fracture were evaluated with X-ray, CT and MRI, including 3 cases in cervical vertebra, 18 cases in thoracic vertebra, and 30 cases in lumbar vertebra. The imaging features were comparatively studied. Results: Radiography showed decreased height of the vertebral body, increased antero-posterior diameter and the transverse diameter, and/or the widened interpedicle distance, the inter-spinous distance, as well as the bony fragment inserted into the vertebral canal in 28 cases(54.90%). X-ray findings similar to the compression fracture were revealed in 20 cases(39.21%). And missed diagnosis was made in 3 cases (5.88%). CT clearly demon-strated the vertebral body vertically or transversely burst crack in 49 cases (96.07%); bony fragment inserted into the vertebral canal and narrowed vertebral canal in 35 cases(68. 62% ); fracture of spinal appendix in 22 cases(43.14%). Meanwhile MRI showed abnormal signals within the spinal cord in 35 cases (68.62%),injured intervertebral disk in 29 cases(56.86% ), extradural hematoma in 12 cases(23.52% ) and torn posterior longitudinal ligament in 6 cases (11.76%). Conclusions: Radiography is the routine examination, while with limited diagnostic value in vertebral burst fracture. These patients who have nervous symptoms with simple compression fracture or unremarkable on X-ray should receive the CT or MRI examination. CT is better than MRI in demonstrating the fracture and the displaced bony fragment, while MRI is superior to CT in showing nervous injuries. CT and MRI will provide comprehensive information guiding clinical treatment of vertebral burst fracture. (authors)

Globally threatened vertebrates on islands with invasive species.

Science.gov (United States)

Spatz, Dena R; Zilliacus, Kelly M; Holmes, Nick D; Butchart, Stuart H M; Genovesi, Piero; Ceballos, Gerardo; Tershy, Bernie R; Croll, Donald A

2017-10-01

Global biodiversity loss is disproportionately rapid on islands, where invasive species are a major driver of extinctions. To inform conservation planning aimed at preventing extinctions, we identify the distribution and biogeographic patterns of highly threatened terrestrial vertebrates (classified by the International Union for Conservation of Nature) and invasive vertebrates on ~465,000 islands worldwide by conducting a comprehensive literature review and interviews with more than 500 experts. We found that 1189 highly threatened vertebrate species (319 amphibians, 282 reptiles, 296 birds, and 292 mammals) breed on 1288 islands. These taxa represent only 5% of Earth's terrestrial vertebrates and 41% of all highly threatened terrestrial vertebrates, which occur in vertebrates was available for 1030 islands (80% of islands with highly threatened vertebrates). Invasive vertebrates were absent from 24% of these islands, where biosecurity to prevent invasions is a critical management tool. On the 76% of islands where invasive vertebrates were present, management could benefit 39% of Earth's highly threatened vertebrates. Invasive mammals occurred in 97% of these islands, with Rattus sp. as the most common invasive vertebrate (78%; 609 islands). Our results provide an important baseline for identifying islands for invasive species eradication and other island conservation actions that reduce biodiversity loss.

Hormonally active phytochemicals and vertebrate evolution.

Science.gov (United States)

Lambert, Max R; Edwards, Thea M

2017-06-01

Living plants produce a diversity of chemicals that share structural and functional properties with vertebrate hormones. Wildlife species interact with these chemicals either through consumption of plant materials or aquatic exposure. Accumulating evidence shows that exposure to these hormonally active phytochemicals (HAPs) often has consequences for behavior, physiology, and fecundity. These fitness effects suggest there is potential for an evolutionary response by vertebrates to HAPs. Here, we explore the toxicological HAP-vertebrate relationship in an evolutionary framework and discuss the potential for vertebrates to adapt to or even co-opt the effects of plant-derived chemicals that influence fitness. We lay out several hypotheses about HAPs and provide a path forward to test whether plant-derived chemicals influence vertebrate reproduction and evolution. Studies of phytochemicals with direct impacts on vertebrate reproduction provide an obvious and compelling system for studying evolutionary toxicology. Furthermore, an understanding of whether animal populations evolve in response to HAPs could provide insightful context for the study of rapid evolution and how animals cope with chemical agents in the environment.

[Correlation analysis of cement leakage with volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence in percutaneous vertebroplasty for osteoporotic vertebral compression fractures].

Science.gov (United States)

Liang, De; Ye, Linqiang; Jiang, Xiaobing; Huang, Weiquan; Yao, Zhensong; Tang, Yongchao; Zhang, Shuncong; Jin, Daxiang

2014-11-01

To investigate the risk factors of cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). Between March 2011 and March 2012, 98 patients with single level OVCF were treated by PVP, and the clinical data were analyzed retrospectively. There were 13 males and 85 females, with a mean age of 77.2 years (range, 54-95 years). The mean disease duration was 43 days (range, 15-120 days), and the mean T score of bone mineral density (BMD) was -3.8 (range, -6.7- -2.5). Bilateral transpedicular approach was used in all the patients. The patients were divided into cement leakage group and no cement leakage group by occurrence of cement leakage based on postoperative CT. Single factor analysis was used to analyze the difference between 2 groups in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, preoperative vertebral body wall incompetence, cement volume, and volume ratio of intravertebral bone cement to vertebral body. All relevant factors were introduced to logistic regression analysis to analyze the risk factors of cement leakage. All procedures were performed successfully. The mean operation time was 40 minutes (range, 30-50 minutes), and the mean volume ratio of intravertebral bone cement to vertebral body was 24.88% (range, 7.84%-38.99%). Back pain was alleviated significantly in all the patients postoperatively. All patients were followed up with a mean time of 8 months (range, 6-12 months). Cement leakage occurred in 49 patients. Single factor analysis showed that there were significant differences in the volume ratio of intravertebral bone cement to vertebral body and preoperative vertebral body wall incompetence between 2 groups (P 0.05). The logistic regression analysis showed that the volume ratio of intravertebral bone cement to vertebral body (P

Evolution of the vertebrate claudin gene family: insights from a basal vertebrate, the sea lamprey.

Science.gov (United States)

Mukendi, Christian; Dean, Nicholas; Lala, Rushil; Smith, Jeramiah; Bronner, Marianne E; Nikitina, Natalya V

2016-01-01

Claudins are major constituents of tight junctions, contributing both to their intercellular sealing and selective permeability properties. While claudins and claudin-like molecules are present in some invertebrates, the association of claudins with tight junctions has been conclusively documented only in vertebrates. Here we report the sequencing, phylogenetic analysis and comprehensive spatiotemporal expression analysis of the entire claudin gene family in the basal extant vertebrate, the sea lamprey. Our results demonstrate that clear orthologues to about half of all mammalian claudins are present in the lamprey, suggesting that at least one round of whole genome duplication contributed to the diversification of this gene family. Expression analysis revealed that claudins are expressed in discrete and specific domains, many of which represent vertebrate-specific innovations, such as in cranial ectodermal placodes and the neural crest; whereas others represent structures characteristic of chordates, e.g. pronephros, notochord, somites, endostyle and pharyngeal arches. By comparing the embryonic expression of claudins in the lamprey to that of other vertebrates, we found that ancestral expression patterns were often preserved in higher vertebrates. Morpholino mediated loss of Cldn3b demonstrated a functional role for this protein in placode and pharyngeal arch morphogenesis. Taken together, our data provide novel insights into the origins and evolution of the claudin gene family and the significance of claudin proteins in the evolution of vertebrates.

Vertebral chondroblastoma

International Nuclear Information System (INIS)

Ilaslan, Hakan; Sundaram, Murali; Unni, Krishnan K.

2003-01-01

To determine the age distribution, gender, incidence, and imaging findings of vertebral chondroblastoma, and to compare our series with findings from case reports in the world literature.Design and patients Case records and imaging findings of nine histologically documented vertebral chondroblastomas were retrospectively reviewed for patient age, gender, vertebral column location and level, morphology, matrix, edema, soft tissue mass, spinal canal invasion, and metastases. Our findings were compared with a total of nine patients identified from previous publications in the world literature. The histologic findings in our cases was re-reviewed for diagnosis and specifically for features of calcification and secondary aneurysmal bone cyst (ABC). Clinical follow-up was requested from referring institutions. Nine of 856 chondroblastomas arose in vertebrae (incidence 1.4%; thoracic 5, lumbar 1, cervical 2, sacral 1). There were six males and three females ranging in age from 5 to 41 years (mean 28 years). Satisfactory imaging from seven patients revealed the tumor to arise from the posterior elements in four and the body in three. All tumors were expansive, six of seven were aggressive, and the spinal canal was significantly narrowed by bone or soft tissue mass in six. In one patient canal invasion was minimal. Calcification was pronounced in two and subtle in four. The sole nonaggressive-appearing tumor was heavily mineralized. Bony edema and secondary ABC were not seen on MR imaging. None of the cases had microscopic features of significant secondary ABC. Calcification, and specifically ''chicken wire'' calcification, was identified in two patients. Pulmonary metastases occurred in none. Vertebral chondroblastoma is a rare neoplasm that presents later in life than its appendicular counterpart. On imaging it is aggressive in appearance with bone destruction, soft tissue mass, and spinal canal invasion. The lesions contain variable amounts of mineral. Secondary

Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: An Economic Analysis.

Science.gov (United States)

2016-01-01

Untreated vertebral compression fractures can have serious clinical consequences and impose a considerable impact on patients' quality of life and on caregivers. Since non-surgical management of these fractures has limited effectiveness, vertebral augmentation procedures are gaining acceptance in clinical practice for pain control and fracture stabilization. The objective of this analysis was to determine the cost-effectiveness and budgetary impact of kyphoplasty or vertebroplasty compared with non-surgical management for the treatment of vertebral compression fractures in patients with cancer. We performed a systematic review of health economic studies to identify relevant studies that compare the cost-effectiveness of kyphoplasty or vertebroplasty with non-surgical management for the treatment of vertebral compression fractures in adults with cancer. We also performed a primary cost-effectiveness analysis to assess the clinical benefits and costs of kyphoplasty or vertebroplasty compared with non-surgical management in the same population. We developed a Markov model to forecast benefits and harms of treatments, and corresponding quality-adjusted life years and costs. Clinical data and utility data were derived from published sources, while costing data were derived using Ontario administrative sources. We performed sensitivity analyses to examine the robustness of the results. In addition, a 1-year budget impact analysis was performed using data from Ontario administrative sources. Two scenarios were explored: (a) an increase in the total number of vertebral augmentation procedures performed among patients with cancer in Ontario, maintaining the current proportion of kyphoplasty versus vertebroplasty; and (b) no increase in the total number of vertebral augmentation procedures performed among patients with cancer in Ontario but an increase in the proportion of kyphoplasties versus vertebroplasties. The base case considered each of kyphoplasty and vertebroplasty

Imaging of vertebral fracture in osteoporosis

International Nuclear Information System (INIS)

Skowronska-Jozwiak, E.; Lewinski, A.; Bieganski, T.

2008-01-01

Vertebral collapses are the most frequent fractures in osteoporosis. They are often overlooked, although their presence is a strong risk factor for development of new fractures. Lateral radiographs of the spine are the accepted standard for assessment of fractures. Qualitative (visual), semiquantitative and quantitative (morphometric) techniques are useful in determining the compressive deformities of vertebral bodies. In the present paper, the advantages and the disadvantages of these methods are discussed. The improvement of scan quality allows to use DXA technique to diagnose the fractures, in both - the visual and the morphometric way. The vertebral morphologic assessment also seems to be an important diagnostic tool in pediatric osteoporosis. Application of multidetector CT and especially MR in vertebral imaging of osteoporosis, improves the sensitivity of fracture detection and enables the differentiation of benign from malignant vertebral body collapses. (author)

Tracheal Atresia with Segmental Esophageal Duplication: An Unusual Anatomic Arrangement.

Science.gov (United States)

Gaerty, Kirsten; Thomas, Joseph T; Petersen, Scott; Tan, Edwin; Kumar, Sailesh; Gardener, Glenn; Armes, Jane

2016-01-01

An unusual anatomic configuration of segmental tracheal agenesis/atresia with esophageal duplication on autopsy in a fetus that demised in utero at 29 weeks is reported. The mother was scanned initially for a cardiac anomaly at 20 weeks and on follow-up scan at 27 weeks had polyhydramnios and underwent amnioreduction. The final autopsy diagnosis was vertebral, ano-rectal, cardiac, tracheoesophageal, renal, and limb malformations (VACTERL). We discuss the autopsy findings along with the embryological mechanisms and compare the configuration with Floyd's classification for tracheal agenesis. The difficulties in prenatal diagnosis are discussed.

Complementary striped expression patterns of NK homeobox genes during segment formation in the annelid Platynereis.

Science.gov (United States)

Saudemont, Alexandra; Dray, Nicolas; Hudry, Bruno; Le Gouar, Martine; Vervoort, Michel; Balavoine, Guillaume

2008-05-15

NK genes are related pan-metazoan homeobox genes. In the fruitfly, NK genes are clustered and involved in patterning various mesodermal derivatives during embryogenesis. It was therefore suggested that the NK cluster emerged in evolution as an ancestral mesodermal patterning cluster. To test this hypothesis, we cloned and analysed the expression patterns of the homologues of NK cluster genes Msx, NK4, NK3, Lbx, Tlx, NK1 and NK5 in the marine annelid Platynereis dumerilii, a representative of trochozoans, the third great branch of bilaterian animals alongside deuterostomes and ecdysozoans. We found that most of these genes are involved, as they are in the fly, in the specification of distinct mesodermal derivatives, notably subsets of muscle precursors. The expression of the homologue of NK4/tinman in the pulsatile dorsal vessel of Platynereis strongly supports the hypothesis that the vertebrate heart derived from a dorsal vessel relocated to a ventral position by D/V axis inversion in a chordate ancestor. Additionally and more surprisingly, NK4, Lbx, Msx, Tlx and NK1 orthologues are expressed in complementary sets of stripes in the ectoderm and/or mesoderm of forming segments, suggesting an involvement in the segment formation process. A potentially ancient role of the NK cluster genes in segment formation, unsuspected from vertebrate and fruitfly studies so far, now deserves to be investigated in other bilaterian species, especially non-insect arthropods and onychophorans.

CIRSE Guidelines on Percutaneous Vertebral Augmentation

Energy Technology Data Exchange (ETDEWEB)

Tsoumakidou, Georgia, E-mail: gtsoumakidou@yahoo.com; Too, Chow Wei, E-mail: spyder55@gmail.com; Koch, Guillaume, E-mail: guillaume.koch@gmail.com; Caudrelier, Jean, E-mail: jean.caudrelier@chru-strasbourg.fr; Cazzato, Roberto Luigi, E-mail: gigicazzato@hotmail.it; Garnon, Julien, E-mail: juliengarnon@gmail.com; Gangi, Afshin, E-mail: gangi@unistra.fr [Strasbourg University Hospital, Interventional Radiology Department (France)

2017-03-15

Vertebral compression fracture (VCF) is an important cause of severe debilitating back pain, adversely affecting quality of life, physical function, psychosocial performance, mental health and survival. Different vertebral augmentation procedures (VAPs) are used in order to consolidate the VCFs, relief pain,and whenever posible achieve vertebral body height restoration. In the present review we give the indications, contraindications, safety profile and outcomes of the existing percutaneous VAPs.

Light adaptation and the evolution of vertebrate photoreceptors.

Science.gov (United States)

Morshedian, Ala; Fain, Gordon L

2017-07-15

Lamprey are cyclostomes, a group of vertebrates that diverged from lines leading to jawed vertebrates (including mammals) in the late Cambrian, 500 million years ago. It may therefore be possible to infer properties of photoreceptors in early vertebrate progenitors by comparing lamprey to other vertebrates. We show that lamprey rods and cones respond to light much like rods and cones in amphibians and mammals. They operate over a similar range of light intensities and adapt to backgrounds and bleaches nearly identically. These correspondences are pervasive and detailed; they argue for the presence of rods and cones very early in the evolution of vertebrates with properties much like those of rods and cones in existing vertebrate species. The earliest vertebrates were agnathans - fish-like organisms without jaws, which first appeared near the end of the Cambrian radiation. One group of agnathans became cyclostomes, which include lamprey and hagfish. Other agnathans gave rise to jawed vertebrates or gnathostomes, the group including all other existing vertebrate species. Because cyclostomes diverged from other vertebrates 500 million years ago, it may be possible to infer some of the properties of the retina of early vertebrate progenitors by comparing lamprey to other vertebrates. We have previously shown that rods and cones in lamprey respond to light much like photoreceptors in other vertebrates and have a similar sensitivity. We now show that these affinities are even closer. Both rods and cones adapt to background light and to bleaches in a manner almost identical to other vertebrate photoreceptors. The operating range in darkness is nearly the same in lamprey and in amphibian or mammalian rods and cones; moreover background light shifts response-intensity curves downward and to the right over a similar range of ambient intensities. Rods show increment saturation at about the same intensity as mammalian rods, and cones never saturate. Bleaches decrease

Surgical strategy for intra- and extra-vertebral dumbbell-shaped tumors

Directory of Open Access Journals (Sweden)

SUN Li-yong

2013-12-01

Full Text Available Objective To investigate the clinical features and surgical strategy of intra- and extra-vertebral dumbbell-shaped tumors. Methods Clinical data of 39 patients with intra- and extra-vertebral tumor were retrospectively studied. The tumors were removed via posterior midline approach in 33 patients, and via posterior combined with anterior approach in 6 patients. Thirty patients underwent tumor resection and internal fixation. Lateral mass screw fixation was performed in the level of C3-7, while the pedicular screw fixation was performed in the level of C2 and thoracic and lumbar segment. Results Tumors were totally excised in all the cases. The patients were followed-up for 6 months to 5 years with an average of 18.67 months. Pain relief occured in 29 cases, of whom the average Visual Analogue Scale (VAS score decreased from (7.51 ± 1.05 before surgery to (3.17 ± 1.17 24 h after surgery (P < 0.05. The numbness area emerged or enlarged in 12 cases and was unchanged in 3 cases. The average American Spinal Injury Association (ASIA sensation score decreased from (218.67 ± 2.80 before surgery to (213.33 ± 2.16 24 h after surgery (P < 0.05, but it increased to (216.78 ± 1.47 6 months after operation (P < 0.05. The motor function improved in 18 cases, and ASIA motor function score improved from (92.33 ± 1.63 before surgery to (95.05 ± 1.41 6 months after operation (P < 0.05. No tumor recurrence and secondary spinal deformity were found. Conclusion Most cases of dumbbell-shaped intra- and extra-vertebral tumor can be totally removed with one-session microsurgery. In the cases with bony erosion caused by tumor and facetectomy, concurrent internal fixation and fusion were recommended in order to maintain spinal stability.

A Review of the Segmental Diameter of the Healthy Human Spinal Cord.

Science.gov (United States)

Frostell, Arvid; Hakim, Ramil; Thelin, Eric Peter; Mattsson, Per; Svensson, Mikael

2016-01-01

Knowledge of the average size and variability of the human spinal cord can be of importance when treating pathological conditions in the spinal cord. Data on healthy human spinal cord morphometrics have been published for more than a century using different techniques of measurements, but unfortunately, comparison of results from different studies is difficult because of the different anatomical landmarks used as reference points along the craniocaudal axis for the measurements. The aim of this review was to compute population estimates of the transverse and anteroposterior diameter of the human spinal cord by comparing and combining previously published data on a normalized craniocaudal axis. We included 11 studies presenting measurements of spinal cord cross-sectional diameters, with a combined sample size ranging from 15 to 488 subjects, depending on spinal cord level. Based on five published studies presenting data on the lengths of the segments of the spinal cord and vertebral column, we calculated the relative positions of all spinal cord neuronal segments and vertebral bony segments and mapped measurements of spinal cord size to a normalized craniocaudal axis. This mapping resulted in better alignment between studies and allowed the calculation of weighted averages and standard deviations (SDs) along the spinal cord. These weighted averages were smoothed using a generalized additive model to yield continuous population estimates for transverse and anteroposterior diameter and associated SDs. The spinal cord had the largest transverse diameter at spinal cord neuronal segment C5 (13.3 ± 2.2), decreased to segment T8 (8.3 ± 2.1), and increased slightly again to 9.4 ± 1.5 at L3. The anteroposterior diameter showed less variation in size along the spinal cord at C5 (7.4 ± 1.6), T8 (6.3 ± 2.0), and L3 (7.5 ± 1.6). All estimates are presented in millimeters ± 2 SDs. We conclude that segmental transverse and anteroposterior

An invertebrate stomach's view on vertebrate ecology

DEFF Research Database (Denmark)

Calvignac-Spencer, Sébastien; Leendertz, Fabian H.; Gilbert, Tom

2013-01-01

Recent studies suggest that vertebrate genetic material ingested by invertebrates (iDNA) can be used to investigate vertebrate ecology. Given the ubiquity of invertebrates that feed on vertebrates across the globe, iDNA might qualify as a very powerful tool for 21st century population...

Vertebral architecture in the earliest stem tetrapods.

Science.gov (United States)

Pierce, Stephanie E; Ahlberg, Per E; Hutchinson, John R; Molnar, Julia L; Sanchez, Sophie; Tafforeau, Paul; Clack, Jennifer A

2013-02-14

The construction of the vertebral column has been used as a key anatomical character in defining and diagnosing early tetrapod groups. Rhachitomous vertebrae--in which there is a dorsally placed neural arch and spine, an anteroventrally placed intercentrum and paired, posterodorsally placed pleurocentra--have long been considered the ancestral morphology for tetrapods. Nonetheless, very little is known about vertebral anatomy in the earliest stem tetrapods, because most specimens remain trapped in surrounding matrix, obscuring important anatomical features. Here we describe the three-dimensional vertebral architecture of the Late Devonian stem tetrapod Ichthyostega using propagation phase-contrast X-ray synchrotron microtomography. Our scans reveal a diverse array of new morphological, and associated developmental and functional, characteristics, including a possible posterior-to-anterior vertebral ossification sequence and the first evolutionary appearance of ossified sternal elements. One of the most intriguing features relates to the positional relationships between the vertebral elements, with the pleurocentra being unexpectedly sutured or fused to the intercentra that directly succeed them, indicating a 'reverse' rhachitomous design. Comparison of Ichthyostega with two other stem tetrapods, Acanthostega and Pederpes, shows that reverse rhachitomous vertebrae may be the ancestral condition for limbed vertebrates. This study fundamentally revises our current understanding of vertebral column evolution in the earliest tetrapods and raises questions about the presumed vertebral architecture of tetrapodomorph fish and later, more crownward, tetrapods.

Vertebrate pressure-gradient receivers

DEFF Research Database (Denmark)

Christensen-Dalsgaard, Jakob

2011-01-01

The eardrums of all terrestrial vertebrates (tetrapods) are connected through Eustachian tubes or interaural canals. In some of the animals, these connections create pressure-gradient directionality, an enhanced directionality by interaction of sound arriving at both sides of the eardrum and stro......The eardrums of all terrestrial vertebrates (tetrapods) are connected through Eustachian tubes or interaural canals. In some of the animals, these connections create pressure-gradient directionality, an enhanced directionality by interaction of sound arriving at both sides of the eardrum....... Recent vertebrates form a continuum from perfect interaural transmission (0 dB in a certain frequency band) and pronounced eardrum directionality (30-40 dB) in the lizards, over somewhat attenuated transmission and limited directionality in birds and frogs, to the strongly attenuated interaural...

Segmentation and registration duality from echographic images by use of physiological and morphological knowledge; Segmentation et recalage d`images echographiques par utilisation de connaissances physiologiques et morphologiques

Energy Technology Data Exchange (ETDEWEB)

Ionescu, G

1998-12-04

Echographic imaging could potentially play a major role in the field of Computer Assisted Surgery (CAS). For doctors and surgeons to make full use of tool in planning and executing surgical operations, they also need user-friendly automatic software based on fast, precise and reliable algorithms. The main goal of this thesis is to take advantage of the segmentation/registration duality to extract the relevant information from echo graphical images. This information will allow the precise and automatic registration both of anatomical structures contained in the pre-operative model and of per-operative data contained in echographic images. The result of registration will be further to guide a computer-assisted tool. In the first part we propose different methods for filtering, segmentation and calibration of echographic images. The development of fast, precise and reliable algorithms is emphasized. The second part concerns the segmentation-registration duality and the corrections of elastic deformations of soft tissues. High-level segmentation algorithms for echographic images were developed. They are based on results of low -level segmentation, a priori anatomical knowledge as well as on information provided by the pre-operative model. The third part deals with detailed descriptions of applications and interpretation of results. The cases studied include: screwing inside the vertebral pedicles, ilio-sacral screwing, prostatic radiotherapy and puncture of pericardial effusion. Future developments for this approach are discussed. (author)

Prevalent Vertebral Fractures in Black Women and White Women

OpenAIRE

Cauley, Jane A; Palermo, Lisa; Vogt, Molly; Ensrud, Kristine E; Ewing, Susan; Hochberg, Marc; Nevitt, Michael C; Black, Dennis M

2008-01-01

Vertebral fractures are the most common osteoporotic fracture. Hip and clinical fractures are less common in black women, but there is little information on vertebral fractures. We studied 7860 white and 472 black women ≥65 yr of age enrolled in the Study of Osteoporotic Fractures. Prevalent vertebral fractures were identified from lateral spine radiographs using vertebral morphometry and defined if any vertebral height ratio was >3 SD below race-specific means for each vertebral level. Infor...

Evolution of circadian organization in vertebrates

Directory of Open Access Journals (Sweden)

M. Menaker

1997-03-01

Full Text Available Circadian organization means the way in which the entire circadian system above the cellular level is put together physically and the principles and rules that determine the interactions among its component parts which produce overt rhythms of physiology and behavior. Understanding this organization and its evolution is of practical importance as well as of basic interest. The first major problem that we face is the difficulty of making sense of the apparently great diversity that we observe in circadian organization of diverse vertebrates. Some of this diversity falls neatly into place along phylogenetic lines leading to firm generalizations: i in all vertebrates there is a "circadian axis" consisting of the retinas, the pineal gland and the suprachiasmatic nucleus (SCN, ii in many non-mammalian vertebrates of all classes (but not in any mammals the pineal gland is both a photoreceptor and a circadian oscillator, and iii in all non-mammalian vertebrates (but not in any mammals there are extraretinal (and extrapineal circadian photoreceptors. An interesting explanation of some of these facts, especially the differences between mammals and other vertebrates, can be constructed on the assumption that early in their evolution mammals passed through a "nocturnal bottleneck". On the other hand, a good deal of the diversity among the circadian systems of vertebrates does not fall neatly into place along phylogenetic lines. In the present review we will consider how we might better understand such "phylogenetically incoherent" diversity and what sorts of new information may help to further our understanding of the evolution of circadian organization in vertebrates

Vertebral chondroblastoma

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Ilaslan, Hakan; Sundaram, Murali [Department of Radiology, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905 (United States); Unni, Krishnan K. [Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905 (United States)

2003-02-01

To determine the age distribution, gender, incidence, and imaging findings of vertebral chondroblastoma, and to compare our series with findings from case reports in the world literature.Design and patients Case records and imaging findings of nine histologically documented vertebral chondroblastomas were retrospectively reviewed for patient age, gender, vertebral column location and level, morphology, matrix, edema, soft tissue mass, spinal canal invasion, and metastases. Our findings were compared with a total of nine patients identified from previous publications in the world literature. The histologic findings in our cases was re-reviewed for diagnosis and specifically for features of calcification and secondary aneurysmal bone cyst (ABC). Clinical follow-up was requested from referring institutions. Nine of 856 chondroblastomas arose in vertebrae (incidence 1.4%; thoracic 5, lumbar 1, cervical 2, sacral 1). There were six males and three females ranging in age from 5 to 41 years (mean 28 years). Satisfactory imaging from seven patients revealed the tumor to arise from the posterior elements in four and the body in three. All tumors were expansive, six of seven were aggressive, and the spinal canal was significantly narrowed by bone or soft tissue mass in six. In one patient canal invasion was minimal. Calcification was pronounced in two and subtle in four. The sole nonaggressive-appearing tumor was heavily mineralized. Bony edema and secondary ABC were not seen on MR imaging. None of the cases had microscopic features of significant secondary ABC. Calcification, and specifically ''chicken wire'' calcification, was identified in two patients. Pulmonary metastases occurred in none. Vertebral chondroblastoma is a rare neoplasm that presents later in life than its appendicular counterpart. On imaging it is aggressive in appearance with bone destruction, soft tissue mass, and spinal canal invasion. The lesions contain variable amounts of mineral

Simplified Model Surgery Technique for Segmental Maxillary Surgeries

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Namit Nagar

2011-01-01

Full Text Available Model surgery is the dental cast version of cephalometric prediction of surgical results. Patients having vertical maxillary excess with prognathism invariably require Lefort I osteotomy with maxillary segmentation and maxillary first premolar extractions during surgery. Traditionally, model surgeries in these cases have been done by sawing the model through the first premolar interproximal area and removing that segment. This clinical innovation employed the use of X-ray film strips as separators in maxillary first premolar interproximal area. The method advocated is a time-saving procedure where no special clinical or laboratory tools, such as plaster saw (with accompanying plaster dust, were required and reusable separators were made from old and discarded X-ray films.

Factors for vertebral artery injury accompanied by cervical trauma

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Murata, Masaaki; Shingu, Hikosuke; Kimura, Isao; Nasu, Yoshiro; Shiotani, Akihide [San-in Rosai Hospital, Yonago, Tottori (Japan). Spine and Low Back Pain Center

2001-09-01

Injury of the vertebral artery with cerebellar and brain stem infarction is a complication of cervical vertebral trauma. However, the pathogenesis and etiological factors remain to be clarified. In this study, we investigated patients with cervical vertebral and cord injury. This study included 51 patients with cervical vertebral and cord injury who were treated in our department. In these patients, plain X-ray, CT, MRI, and MRA findings were examined. The incidence of vertebral arterial injury was 33.3% (17 of 51 patients with cervical vertebral trauma). In 11 of the 17 patients, dislocation fracture was noted, comprising a markedly high percentage (64.7%). Particularly, vertebral arterial injury was commonly observed in patients with a large dislocation distance and severe paralysis. Cerebellar and brain stem infarction related to vertebral arterial injury was observed in 5 of the 17 patients (29.4%). No infarction developed in patients 50 years old or younger. Infarction was detected in relatively elderly patients. Vertebral arterial injury and cerebellar/brain stem infarction related to cervical vertebral trauma were frequently observed in patients with high energy injury. However, these disorders commonly occurred in elderly patients. Therefore, age-related factors such as arteriosclerosis may also be closely involved. In the acute stage, the state of the vertebral artery should be evaluated by MRA and MRI. Among patients with vertebral arterial injury, caution is needed during follow-up those with risk factors such as high energy injury and advanced age. (author)

Factors for vertebral artery injury accompanied by cervical trauma

International Nuclear Information System (INIS)

Murata, Masaaki; Shingu, Hikosuke; Kimura, Isao; Nasu, Yoshiro; Shiotani, Akihide

2001-01-01

Injury of the vertebral artery with cerebellar and brain stem infarction is a complication of cervical vertebral trauma. However, the pathogenesis and etiological factors remain to be clarified. In this study, we investigated patients with cervical vertebral and cord injury. This study included 51 patients with cervical vertebral and cord injury who were treated in our department. In these patients, plain X-ray, CT, MRI, and MRA findings were examined. The incidence of vertebral arterial injury was 33.3% (17 of 51 patients with cervical vertebral trauma). In 11 of the 17 patients, dislocation fracture was noted, comprising a markedly high percentage (64.7%). Particularly, vertebral arterial injury was commonly observed in patients with a large dislocation distance and severe paralysis. Cerebellar and brain stem infarction related to vertebral arterial injury was observed in 5 of the 17 patients (29.4%). No infarction developed in patients 50 years old or younger. Infarction was detected in relatively elderly patients. Vertebral arterial injury and cerebellar/brain stem infarction related to cervical vertebral trauma were frequently observed in patients with high energy injury. However, these disorders commonly occurred in elderly patients. Therefore, age-related factors such as arteriosclerosis may also be closely involved. In the acute stage, the state of the vertebral artery should be evaluated by MRA and MRI. Among patients with vertebral arterial injury, caution is needed during follow-up those with risk factors such as high energy injury and advanced age. (author)

Risk of vertebral insufficiency fractures in relation to compressive strength predicted by quantitative computed tomography

International Nuclear Information System (INIS)

Biggemann, M.; Hilweg, D.; Seidel, S.; Horst, M.; Brinckmann, P.

1991-01-01

Vertebral insufficiency fractures may result from excessive loading of normal and routine loading of osteoporotic spines. Fractures occur when the mechanical load exceeds the vertebral compressive strength, i.e., the maximum load a vertebra can tolerate. Vertebral compressive strength is determined by trabecular bone density and the size of end-plate area. Both parameters can be measured non-invasively by quanti-tative computed tomography (QCT). In 75 patients compressive strength (i.e., trabecular bone density and endplate area) of the vertebra L3 was determined using QCT. In addition, conventional radiographs of the spines were analysed for the prevalence of insufficiency fractures in each case. By relating fracture prevalence to strength, 3 fracture risk groups were found: a high-risk group with strength values of L3 5 kN and a fracture risk near 0 percent. Biomechanical measurements and model calculations indicate that spinal loads of 3 to 4 kN at L3/4 will be common in everyday activities. These data and the results described above suggest that spines with strength values of L3<3 kN are at an extremely high risk of insufficiency fractures in daily life. Advantages of fracture risk assessment by strength determination over risk estimation based on clinically used trabecular bone density measurements are discussed. (author). 18 refs.; 4 figs

Bilateral Internal Carotid Artery Occlusion, External Carotid Artery Stenosis, and Vertebral Artery Kinking: May It Be Asymptomatic?

Science.gov (United States)

Fatic, Nikola; Jaffer, Usman; Ivana, Saicic; Gordana, Globarevic-Vukcevic; Markovic, Dragan; Kostic, Dusan; Davidovic, Lazar

2017-10-01

The clinical spectrum of internal carotid artery occlusion ranges from being a completely asymptomatic occlusion to a devastating stroke or death. The prevalence of asymptomatic internal carotid artery occlusion is unknown, particularly for bilateral occlusion. The distal branches of the external carotid artery anastomose with distal branches of the internal carotid artery provide important sources of collateral circulation to the brain. Stenosis of the external carotid artery with ipsilateral/bilateral internal occlusion may result in ischemic sequelae. Coiling or kinking of the vertebral artery is a rare morphological entity that is infrequently reported because it remains asymptomatic and has no clinical relevance. Currently, there is little evidence to support management strategies for this disease entity and no official recommendations for asymptomatic bilateral carotid artery occlusion. We present a case of a 62-year-old female with asymptomatic bilateral internal carotid artery occlusion, bilateral external carotid artery stenoses, and bilateral kinking of the vertebral artery at the V2 segment, who has been successfully managed conservatively for over 5 years. An individualized approach to management of patients with bilateral internal carotid artery occlusion, especially in combination with external carotid artery stenosis and elongation malformations of the vertebral artery is key to a successful strategy. Copyright © 2017 Elsevier Inc. All rights reserved.

Magnetic Resonance Enhancement Patterns at the Different Ages of Symptomatic Osteoporotic Vertebral Compression Fractures

Energy Technology Data Exchange (ETDEWEB)

You, Ja Yeon; Lee, Joon Woo; Kim, Jung Eun; Kang, Heung Sik [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

2013-06-15

To investigate the magnetic resonance (MR) enhancement patterns of symptomatic osteoporotic vertebral compression fracture (VCF) according to the fracture age, based on the successful single-level percutaneous vertebroplasty (PVP) cases. The study included 135 patients who underwent contrast-enhanced MR imaging and successful PVP from 2005 to 2010 due to a single- level osteoporotic VCF. Two radiologists blinded to the fracture age evaluated the MR enhancement patterns in consensus. The MR enhancement patterns were classified according to the enhancing proportion to the vertebral height and the presence or extent of a non-enhancing cleft within the enhancing area on sagittal plane. The Fisher' exact test, Kruskal-Wallis test and Mann-Whitney U test were performed to assess the differences in the MR enhancement patterns according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. A diffuse enhancing area can be seen in not only the hyperacute and acute VCFs but also the chronic symptomatic VCFs. Symptomatic VCFs having a segmental enhancing area were all included in the hyperacute or acute stage. Most symptomatic osteoporotic VCFs had a non-enhancing cleft in the enhanced vertebral body (128/135, 94.8%). There was no statistical difference of the enhancement pattern according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. The most common pattern is a non-enhancing cleft within a diffuse enhanced vertebra.

Magnetic Resonance Enhancement Patterns at the Different Ages of Symptomatic Osteoporotic Vertebral Compression Fractures

International Nuclear Information System (INIS)

You, Ja Yeon; Lee, Joon Woo; Kim, Jung Eun; Kang, Heung Sik

2013-01-01

To investigate the magnetic resonance (MR) enhancement patterns of symptomatic osteoporotic vertebral compression fracture (VCF) according to the fracture age, based on the successful single-level percutaneous vertebroplasty (PVP) cases. The study included 135 patients who underwent contrast-enhanced MR imaging and successful PVP from 2005 to 2010 due to a single- level osteoporotic VCF. Two radiologists blinded to the fracture age evaluated the MR enhancement patterns in consensus. The MR enhancement patterns were classified according to the enhancing proportion to the vertebral height and the presence or extent of a non-enhancing cleft within the enhancing area on sagittal plane. The Fisher' exact test, Kruskal-Wallis test and Mann-Whitney U test were performed to assess the differences in the MR enhancement patterns according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. A diffuse enhancing area can be seen in not only the hyperacute and acute VCFs but also the chronic symptomatic VCFs. Symptomatic VCFs having a segmental enhancing area were all included in the hyperacute or acute stage. Most symptomatic osteoporotic VCFs had a non-enhancing cleft in the enhanced vertebral body (128/135, 94.8%). There was no statistical difference of the enhancement pattern according to the fracture age. Symptomatic VCFs show variable MR enhancement patterns in all fracture ages. The most common pattern is a non-enhancing cleft within a diffuse enhanced vertebra.

Vertebral body spread in thoracolumbar burst fractures can predict posterior construct failure.

Science.gov (United States)

De Iure, Federico; Lofrese, Giorgio; De Bonis, Pasquale; Cultrera, Francesco; Cappuccio, Michele; Battisti, Sofia

2018-06-01

The load sharing classification (LSC) laid foundations for a scoring system able to indicate which thoracolumbar fractures, after short-segment posterior-only fixations, would need longer instrumentations or additional anterior supports. We analyzed surgically treated thoracolumbar fractures, quantifying the vertebral body's fragment displacement with the aim of identifying a new parameter that could predict the posterior-only construct failure. This is a retrospective cohort study from a single institution. One hundred twenty-one consecutive patients were surgically treated for thoracolumbar burst fractures. Grade of kyphosis correction (GKC) expressed radiological outcome; Oswestry Disability Index and visual analog scale were considered. One hundred twenty-one consecutive patients who underwent posterior fixation for unstable thoracolumbar burst fractures were retrospectively evaluated clinically and radiologically. Supplementary anterior fixations were performed in 34 cases with posterior instrumentation failure, determined on clinic-radiological evidence or symptomatic loss of kyphosis correction. Segmental kyphosis angle and GKC were calculated according to the Cobb method. The displacement of fracture fragments was obtained from the mean of the adjacent end plate areas subtracted from the area enclosed by the maximum contour of vertebral fragmentation. The "spread" was derived from the ratio between this subtraction and the mean of the adjacent end plate areas. Analysis of variance, Mann-Whitney, and receiver operating characteristic were performed for statistical analysis. The authors report no conflict of interest concerning the materials or methods used in the present study or the findings specified in this paper. No funds or grants have been received for the present study. The spread revealed to be a helpful quantitative measurement of vertebral body fragment displacement, easily reproducible with the current computed tomography (CT) imaging technologies

Initial non-weight-bearing therapy is important for preventing vertebral body collapse in elderly patients with clinical vertebral fractures

Directory of Open Access Journals (Sweden)

Kishikawa Y

2012-04-01

Full Text Available Yoichi KishikawaKishikawa Orthopaedic Clinic, Saga City, Saga, JapanPurpose: The aim of the present conventional observational study was to compare the clinical outcomes of initial non-weight-bearing therapy and conventional relative rest therapy among elderly patients with clinical vertebral fractures.Methods: In total, 196 consecutive patients with clinical vertebral fractures (mean age: 78 years who were hospitalized for treatment between January 1999 and March 2007 were analyzed. Initial non-weight-bearing therapy consisted of complete bed rest allowing rolling on the bed without any weight-bearing to the spine for 2 weeks, followed by rehabilitation wearing a soft brace. The indications for initial non-weight-bearing therapy were vertebral fracture involving the posterior portion of the vertebral body at the thoraco-lumbar spine, mild neurological deficit, instability of the fracture site, severe pain, multiple vertebral fractures arising from trauma, malalignment at the fracture site, and mild spinal canal stenosis caused by the fracture. Patients who met the indication criteria were treated with initial non-weight-bearing therapy (n = 103, while the other patients were treated with conventional relative rest (n = 93. All the patients were uniformly treated with intramuscular elcatonin to relieve pain. The primary endpoint was progression of the vertebral fracture. The secondary endpoints included bony union and subjective back pain. The follow-up period was 12 weeks.Results: Compared with the conventional relative rest group, the collapse rate of the anterior and posterior portions of the vertebral body was significantly smaller in the initial non-weight-bearing group. The bony union rate was 100% in the initial non-weight-bearing group and 97% in the conventional relative rest group. The number of patients who experienced back pain was significantly lower in the initial non-weight-bearing group than in the conventional relative rest

Vertebral morphometry by dual-energy X-ray absorptiometry

International Nuclear Information System (INIS)

Boyanov, M.

2002-01-01

Vertebral fractures are a key feature of overt osteoporosis. Different X-ray morphometric techniques have been developed for quantification of changes in vertebral body shape. In recent years, a new method was implemented based on dual-energy X-ray absorptiometry. Morphometric X-ray absorptiometry, MXA, is a source of lower radiation and there is no image distortion. Several aspects of its application are under heavy discussion: image quality, accuracy and precision, reference databases, age changes in vertebral shape. The differential diagnosis of vertebral fracture/deformity is difficult. MXA has prove its value in large epidemiological studies on prevalence of vertebral deformities, as well in assessing the effects of different diseases and medications on vertebral body architecture. MXA is a promising method for future research and clinical work. (author)

Trunk muscle activity is modified in osteoporotic vertebral fracture and thoracic kyphosis with potential consequences for vertebral health.

Directory of Open Access Journals (Sweden)

Alison M Greig

Full Text Available This study explored inter-relationships between vertebral fracture, thoracic kyphosis and trunk muscle control in elderly people with osteoporosis. Osteoporotic vertebral fractures are associated with increased risk of further vertebral fractures; but underlying mechanisms remain unclear. Several factors may explain this association, including changes in postural alignment (thoracic kyphosis and altered trunk muscle contraction patterns. Both factors may increase risk of further fracture because of increased vertebral loading and impaired balance, which may increase falls risk. This study compared postural adjustments in 24 individuals with osteoporosis with and without vertebral fracture and with varying degrees of thoracic kyphosis. Trunk muscle electromyographic activity (EMG associated with voluntary arm movements was recorded and compared between individuals with and without vertebral fracture, and between those with low and high thoracic kyphosis. Overall, elderly participants in the study demonstrated co-contraction of the trunk flexor and extensor muscles during forwards arm movements, but those with vertebral fractures demonstrated a more pronounced co-contraction than those without fracture. Individuals with high thoracic kyphosis demonstrated more pronounced alternating flexor and extensor EMG bursts than those with less kyphosis. Co-contraction of trunk flexor and extensor muscles in older individuals contrasts the alternating bursts of antagonist muscle activity in previous studies of young individuals. This may have several consequences, including altered balance efficacy and the potential for increased compressive loads through the spine. Both of these outcomes may have consequences in a population with fragile vertebrae who are susceptible to fracture.

Hemifacial spasm; The value of vertebral angiography

International Nuclear Information System (INIS)

Yang, Hak Seok; Kim, Myung Soon; Han, Yong Pyo

1992-01-01

In order to evaluate the value of vertebral angiography in assesment of hemifacial spasm, We reviewed retrospectively the vertebral angiography of 28 patients (30 cases) with surgically proved hemifacial spasm but normal CT scans of posterior fossa. There were 9 males and 19 females. Angiography revealed vascular focus of hemifacial spasm located at anterior inferior cerebellar artery , posterior inferior cerebellar artery, and vertebral artery in 19, 9, and 2 cases respectively. Right side was involved in 20 cases. All involved vessels were elongated, tortuous, and dilated. In conclusion, vertebral angiography was valuable in evaluating hemifacial spasm of vascular origin in the posterior fossa

MR imaging of tuberculous vertebral osteomyelitis: pictorial review

Energy Technology Data Exchange (ETDEWEB)

Gouliamos, A.D.; Kehagias, D.T.; Lahanis, S.; Moulopoulou, E.S.; Kalovidouris, A.A.; Trakadas, S.J.; Vlahos, L.j. [Dept. of Radiology, University of Athens (Greece); Athanassopoulou, A.A. [Dept. of Radiology, Asklipiion Hospital, Athens (Greece)

2001-04-01

Vertebral osteomyelitis is one of the most common manifestations of tuberculosis. Magnetic resonance imaging is considered the main imaging modality for the diagnosis, the demonstration of the extent of the disease, and follow-up studies. Vertebral destruction involving two consecutive levels with sparing of the intervertebral disc, disc herniation into the vertebral body, epidural involvement, and paraspinal abscess are the most common MRI findings suggestive of tuberculous vertebral osteomyelitis. (orig.)

Role of notochord cells and sclerotome-derived cells in vertebral column development in fugu, Takifugu rubripes: histological and gene expression analyses.

Science.gov (United States)

Kaneko, Takamasa; Freeha, Khalid; Wu, Xiaoming; Mogi, Makoto; Uji, Susumu; Yokoi, Hayato; Suzuki, Tohru

2016-10-01

Despite the common structure of vertebrates, the development of the vertebral column differs widely between teleosts and tetrapods in several respects, including the ossification of the centrum and the function of the notochord. In contrast to tetrapods, vertebral development in teleosts is not fully understood, particularly for large fish with highly ossified bones. We therefore examined the histology and gene expression profile of vertebral development in fugu, Takifugu rubripes, a model organism for genomic research. Ossification of the fugu centrum is carried out by outer osteoblasts expressing col1a1, col2a1, and sparc, and the growing centra completely divide the notochord into double cone-shaped segments that function as intercentral joints. In this process, the notochord basal cells produce a thick notochord sheath exhibiting Alcian-blue-reactive cartilaginous properties and composing the intercentral ligament in cooperation with the external ligament connective tissue. Synthesis of the matrix by the basal cells was ascertained by an in vitro test. Expression of twist2 indicates that this connective tissue is descended from the embryonic sclerotome. Notochord basal cells express sox9, ihhb, shh, and col2a1a, suggesting that the signaling system involved in chondrocyte proliferation and matrix production also functions in notochord cells for notochord sheath formation. We further found that the notochord expression of both ntla and shh is maintained in the fugu vertebral column, whereas it is turned off after embryogenesis in zebrafish. Thus, our results demonstrate that, in contrast to zebrafish, a dynamic morphogenesis and molecular network continues to function in fugu until the establishment of the adult vertebral column.

Organizational heterogeneity of vertebrate genomes.

Science.gov (United States)

Frenkel, Svetlana; Kirzhner, Valery; Korol, Abraham

2012-01-01

Genomes of higher eukaryotes are mosaics of segments with various structural, functional, and evolutionary properties. The availability of whole-genome sequences allows the investigation of their structure as "texts" using different statistical and computational methods. One such method, referred to as Compositional Spectra (CS) analysis, is based on scoring the occurrences of fixed-length oligonucleotides (k-mers) in the target DNA sequence. CS analysis allows generating species- or region-specific characteristics of the genome, regardless of their length and the presence of coding DNA. In this study, we consider the heterogeneity of vertebrate genomes as a joint effect of regional variation in sequence organization superimposed on the differences in nucleotide composition. We estimated compositional and organizational heterogeneity of genome and chromosome sequences separately and found that both heterogeneity types vary widely among genomes as well as among chromosomes in all investigated taxonomic groups. The high correspondence of heterogeneity scores obtained on three genome fractions, coding, repetitive, and the remaining part of the noncoding DNA (the genome dark matter--GDM) allows the assumption that CS-heterogeneity may have functional relevance to genome regulation. Of special interest for such interpretation is the fact that natural GDM sequences display the highest deviation from the corresponding reshuffled sequences.

Organizational heterogeneity of vertebrate genomes.

Directory of Open Access Journals (Sweden)

Svetlana Frenkel

Full Text Available Genomes of higher eukaryotes are mosaics of segments with various structural, functional, and evolutionary properties. The availability of whole-genome sequences allows the investigation of their structure as "texts" using different statistical and computational methods. One such method, referred to as Compositional Spectra (CS analysis, is based on scoring the occurrences of fixed-length oligonucleotides (k-mers in the target DNA sequence. CS analysis allows generating species- or region-specific characteristics of the genome, regardless of their length and the presence of coding DNA. In this study, we consider the heterogeneity of vertebrate genomes as a joint effect of regional variation in sequence organization superimposed on the differences in nucleotide composition. We estimated compositional and organizational heterogeneity of genome and chromosome sequences separately and found that both heterogeneity types vary widely among genomes as well as among chromosomes in all investigated taxonomic groups. The high correspondence of heterogeneity scores obtained on three genome fractions, coding, repetitive, and the remaining part of the noncoding DNA (the genome dark matter--GDM allows the assumption that CS-heterogeneity may have functional relevance to genome regulation. Of special interest for such interpretation is the fact that natural GDM sequences display the highest deviation from the corresponding reshuffled sequences.

Multi-segment foot kinematics and plantar fascia strain during treadmill and overground running

OpenAIRE

Sinclair, Jonathan Kenneth; Taylor, Paul John; Vincent, Hayley

2014-01-01

Although physiologically beneficial, running is known to be associated with a high incidence of chronic injuries. Excessive coronal and transverse plane motions of the foot segments and strain experienced by the plantar fascia are linked to the development of a number of chronic injuries. This study examined differences in multi-segment foot kinematics and plantar fascia strain during treadmill and overground running. Twelve male recreational runners ran at 4.0 m.s-1 in both treadmill and ove...

Short-term CT findings after osteosynthesis of fractures of the vertebral spine

International Nuclear Information System (INIS)

Schroeder, R.J.; Noor, J.; Herzog, H.; Roettgen, R.; Hidajat, N.; Felix, R.; Pflugmacher, R.; Maeurer, J.

2004-01-01

Purpose: evaluation of a correlation between surgical stabilization of fractures of the vertebral spine and postoperative short-term CT findings with special attention to degenerative changes. Materials and methods: The pre- and post-operative CT of 55 patients (43male, 12 female, age: 7 - 73 years, mean = 37.7 years) with traumatic fractures of the vertebral spine who underwent surgical stabilization using an internal fixator were analyzed retrospectively. The interval between surgical intervention and first postoperative CT control did not exceed one week. The interval to the second short-term follow-up CT ranged from 6 up to 24 months (mean: 10.3 ± 2.7 months). The consensus reading of the short-term CT by two experienced radiologists was compared to the pre- and immediately postoperative CT examinations and with the neurologic findings. Statistical analysis was done using the chi-square- or the Fisher's exact-test. Results: no statistically significant correlation (p > 0.05) was found between the patient's age and the postoperative incidence of osteoporosis, spondylarthrosis, scoliosis, spondylolisthesis or disc protrusion after posttraumatic surgical stabilization using an internal fixator. Also, there was no significant correlation between the fracture's type or location, presence of polytraumatization, the technique of surgical intervention, and the incidence of postoperative degenerative changes in the neighboring segments. The thesis has not been verified (p > 0.05) that polysegment stabilization or prior surgical interventions at the vertebral spine with scar induction are responsible for a higher rate of degeneration. The only risk factor observed for postoperative scoliosis was the burst rotation fracture type C1.3 (AO-classification). (orig.) [de

A Simple Predictive Enhancer Syntax for Hindbrain Patterning Is Conserved in Vertebrate Genomes.

Directory of Open Access Journals (Sweden)

Joseph Grice

Full Text Available Determining the function of regulatory elements is fundamental for our understanding of development, disease and evolution. However, the sequence features that mediate these functions are often unclear and the prediction of tissue-specific expression patterns from sequence alone is non-trivial. Previous functional studies have demonstrated a link between PBX-HOX and MEIS/PREP binding interactions and hindbrain enhancer activity, but the defining grammar of these sites, if any exists, has remained elusive.Here, we identify a shared sequence signature (syntax within a heterogeneous set of conserved vertebrate hindbrain enhancers composed of spatially co-occurring PBX-HOX and MEIS/PREP transcription factor binding motifs. We use this syntax to accurately predict hindbrain enhancers in 89% of cases (67/75 predicted elements from a set of conserved non-coding elements (CNEs. Furthermore, mutagenesis of the sites abolishes activity or generates ectopic expression, demonstrating their requirement for segmentally restricted enhancer activity in the hindbrain. We refine and use our syntax to predict over 3,000 hindbrain enhancers across the human genome. These sequences tend to be located near developmental transcription factors and are enriched in known hindbrain activating elements, demonstrating the predictive power of this simple model.Our findings support the theory that hundreds of CNEs, and perhaps thousands of regions across the human genome, function to coordinate gene expression in the developing hindbrain. We speculate that deeply conserved sequences of this kind contributed to the co-option of new genes into the hindbrain gene regulatory network during early vertebrate evolution by linking patterns of hox expression to downstream genes involved in segmentation and patterning, and evolutionarily newer instances may have continued to contribute to lineage-specific elaboration of the hindbrain.

Cranial thoracic vertebral canal stenosis in three juvenile large-breed brachycephalic dogs treated by unilateral hemilaminectomy.

Science.gov (United States)

Miller, Amanda; Marchevsky, Andrew

2017-05-22

To describe the surgical treatment and outcome for juvenile dogs with cranial thoracic vertebral canal stenosis treated by unilateral hemilaminectomy. Case series. Three large-breed brachycephalic dogs of various breeds (Dogue de Bordeaux, Australian Bulldog, Boerboel) with neurological signs consistent with a myelopathy of the third thoracic (T) to third lumbar (L) spinal cord segment. Information on clinical presentation, diagnostic imaging, surgical procedures, postoperative complications, recovery and outcome is described. Neurological signs were present and progressive for two to four weeks prior to surgery and ranged from mild ataxia to paralysis. Cranial thoracic vertebral canal stenosis was diagnosed with computed tomography imaging. Lateral and dorsolateral spinal cord compression was present at multiple sites between T2 and T6. Alternating left and right-sided compressions were common. Surgical treatment was by unilateral, continuous hemilaminectomy over three to six vertebral spaces. Postoperative morbidity was minimal and return of independent ambulation was rapid (median: 13.5 days, range: 2-29 days). Neurological status in one dog worsened four months after surgery due to reoccurrence of osseous compression; unilateral hemilaminectomy was repeated in this dog. Long-term follow-up ranged from six to 10 months; neurological signs had completely resolved in one dog and substantially improved in the other two dogs. Unilateral hemilaminectomy was associated with rapid return of independent ambulation and substantial improvement in neurological scores.

Acquired degenerative changes of the intervertebral segments at and suprajacent to the lumbosacral junction. A radioanatomic analysis of the nondiskal structures of the spinal column and perispinal soft tissues.

Science.gov (United States)

Jinkins, J R

2001-01-01

In earlier evolutionary times, mammals were primarily quadrupeds. However, other bipeds have also been represented during the course of the Earth's several billion year history. In many cases, either the bipedal stance yielded a large tail and hypoplastic upper extremities (e.g., Tyrannosaurus rex and the kangaroo), or it culminated in hypoplasia of the tail and further development and specialization of the upper extremities (e.g., nonhuman primates and human beings). In the human species this relatively recently acquired posture resulted in a more or less pronounced lumbosacral kyphosis. In turn, certain compensatory anatomic features have since occurred. These include the normal characteristic posteriorly directed wedge-shape of the L5 vertebral body and the L5-S1 intervertebral disk; the L4 vertebral body and the L4-L5 disk may be similarly visibly affected. These compensatory mechanisms, however, have proved to be functionally inadequate over the long term of the human life span. Upright posture also leads to increased weight bearing in humans that progressively causes excess stresses at and suprajacent to the lumbosacral junction. These combined factors result in accelerated aging and degenerative changes and a predisposition to frank biomechanical failure of the subcomponents of the spinal column in these spinal segments. One other specific problem that occurs at the lumbosacral junction that predisposes toward premature degeneration is the singular relationship that exists between a normally mobile segment of spine (i.e., the lumbar spine) and a normally immobile one (i.e., the sacrum). It is well known that mobile spinal segments adjacent to congenitally or acquired fused segments have a predilection toward accelerated degenerative changes. The only segment of the spine in which this is invariably normally true is at the lumbosacral junction (i.e., the unfused lumbar spine adjoining the fused sacrum). Nevertheless, biomechanical failures of the human spine

Parallel fuzzy connected image segmentation on GPU.

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Zhuge, Ying; Cao, Yong; Udupa, Jayaram K; Miller, Robert W

2011-07-01

Image segmentation techniques using fuzzy connectedness (FC) principles have shown their effectiveness in segmenting a variety of objects in several large applications. However, one challenge in these algorithms has been their excessive computational requirements when processing large image datasets. Nowadays, commodity graphics hardware provides a highly parallel computing environment. In this paper, the authors present a parallel fuzzy connected image segmentation algorithm implementation on NVIDIA's compute unified device Architecture (CUDA) platform for segmenting medical image data sets. In the FC algorithm, there are two major computational tasks: (i) computing the fuzzy affinity relations and (ii) computing the fuzzy connectedness relations. These two tasks are implemented as CUDA kernels and executed on GPU. A dramatic improvement in speed for both tasks is achieved as a result. Our experiments based on three data sets of small, medium, and large data size demonstrate the efficiency of the parallel algorithm, which achieves a speed-up factor of 24.4x, 18.1x, and 10.3x, correspondingly, for the three data sets on the NVIDIA Tesla C1060 over the implementation of the algorithm on CPU, and takes 0.25, 0.72, and 15.04 s, correspondingly, for the three data sets. The authors developed a parallel algorithm of the widely used fuzzy connected image segmentation method on the NVIDIA GPUs, which are far more cost- and speed-effective than both cluster of workstations and multiprocessing systems. A near-interactive speed of segmentation has been achieved, even for the large data set.

Vertebral body bone strength: the contribution of individual trabecular element morphology.

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Parkinson, I H; Badiei, A; Stauber, M; Codrington, J; Müller, R; Fazzalari, N L

2012-07-01

Although the amount of bone explains the largest amount of variability in bone strength, there is still a significant proportion unaccounted for. The morphology of individual bone trabeculae explains a further proportion of the variability in bone strength and bone elements that contribute to bone strength depending on the direction of loading. Micro-CT imaging enables measurement of bone microarchitecture and subsequently mechanical strength of the same sample. It is possible using micro-CT data to perform morphometric analysis on individual rod and plate bone trabeculae using a volumetric spatial decomposition algorithm and hence determine their contribution to bone strength. Twelve pairs of vertebral bodies (T12/L1 or L4/L5) were harvested from human cadavers, and bone cubes (10 × 10 × 10 mm) were obtained. After micro-CT imaging, a volumetric spatial decomposition algorithm was applied, and measures of individual trabecular elements were obtained. Bone strength was measured in compression, where one bone specimen from each vertebral segment was tested supero-inferiorly (SI) and the paired specimen was tested antero-posteriorly (AP). Bone volume fraction was the strongest individual determinant of SI strength (r(2) = 0.77, p body bone architecture into its constituent morphological elements shows that trabecular element morphology has specific functional roles to assist in maintaining skeletal integrity.

Lumbar Vertebral Canal Diameters in Adult Ugandan Skeletons ...

African Journals Online (AJOL)

Background: Normal values of lumbar vertebral canal diameters are useful in facilitating diagnosis of lumbar vertebral canal stenosis. Various studies have established variation on values between different populations, gender, age, and ethnic groups. Objectives: To determine the lumbar vertebral canal diameters in adult ...

Vertebral Artery Diameter and Flow: Nature or Nurture.

Science.gov (United States)

Tarnoki, Adam Domonkos; Fejer, Bence; Tarnoki, David Laszlo; Littvay, Levente; Lucatelli, Pierleone; Cirelli, Carlo; Fanelli, Fabrizio; Sacconi, Beatrice; Fagnani, Corrado; Medda, Emanuela; Farina, Filippo; Meneghetti, Giorgio; Horvath, Tamas; Pucci, Giacomo; Schillaci, Giuseppe; Stazi, Maria Antonietta; Baracchini, Claudio

2017-09-01

In contrast with the carotid arteries, the vertebral arteries (VAs) show considerable variation in length, caliber, and vessel course. This study investigated whether the variation in diameter and flow characteristics of the VAs might be inherited. A total of 172 Italian twins from Padua, Perugia, and Terni (54 monozygotic, 32 dizygotic) recruited from the Italian Twin Registry underwent B-mode and pulsed-wave Doppler ultrasound assessment of their VAs. VA diameters, peak systolic velocity (PSV) and end diastolic velocity (EDV) were assessed at the level of a horizontal V2 segment. Univariate quantitative genetic modeling was performed. Fourteen percent of the sample had VA hypoplasia. Within pair correlation in monozygotic twins was higher than in dizygotics (.552 vs. .229) for VA diameter. Age- and sex-adjusted genetic effect, under the most parsimonious model, accounted for 54.7% (95% CI: 42.2-69.1%) of the variance of VA diameter, and unshared environmental effect for 45.3% (95% CI: 30.9-57.8%). No heritability was found for the PSV of VA, but shared (34.1%; 95% CI: 16.7-53.7%) and unshared (65.9%; 95% CI: 45.9-83.1%) environmental factors determined the variance. EDV of VA is moderately genetically influenced (42.4%; 95% CI: 16.1-64.9%) and also determined by the unshared environment (57.6%; 95% CI: 34.7-83.7%). The diameter of the VAs is moderately genetically determined. Different factors influence the PSV and EDV of VAs, which may highlight the complex hemodynamic background of VA flow and help to understand the vertebral flow anomalies found by ultrasound. Copyright © 2017 by the American Society of Neuroimaging.

The shape of the human lumbar vertebral canal

OpenAIRE

Zarzur,Edmundo

1996-01-01

Literature on the anatomy of the human vertebral column characterizes the shape of the lumbar vertebral canal as triangular. The purpose of the present study was to determine the precise shape of the lumbar vertebral canal. Ten lumbar vertebral columns of adult male cadavers were dissected. Two transverse sections were performed in the third lumbar vertebra. One section was performed at the level of the lower border of the ligamenta flava, and the other section was performed at the level of t...

A Case of Duplicated Right Vertebral Artery.

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Motomura, Mayuko; Watanabe, Koichi; Tabira, Yoko; Iwanaga, Joe; Matsuuchi, Wakako; Yoshida, Daichi; Saga, Tsuyoshi; Yamaki, Koh-Ichi

2018-04-27

We encountered a case of duplicated right vertebral artery during an anatomical dissection course for medical students in 2015. Two vertebral arteries were found in the right neck of a 91-year-old female cadaver. The proximal leg of the arteries arose from the area between the right subclavian artery and the right common carotid artery that diverged from the brachiocephalic artery. The distal leg arose from the right subclavian artery as expected. The proximal leg entered the transverse foramen of the fourth cervical vertebra and the distal leg entered the transverse foramen of the sixth cervical vertebra. The two right vertebral arteries joined to form one artery just after the origin of the right vertebral artery of the brachiocephalic artery entered the transverse foramen of the fourth cervical vertebra. This artery then traveled up in the transverse foramina and became the basilar artery, joining with the left vertebral artery. We discuss the embryological origin of this case and review previously reported cases.

Innate immunity in vertebrates: an overview.

Science.gov (United States)

Riera Romo, Mario; Pérez-Martínez, Dayana; Castillo Ferrer, Camila

2016-06-01

Innate immunity is a semi-specific and widely distributed form of immunity, which represents the first line of defence against pathogens. This type of immunity is critical to maintain homeostasis and prevent microbe invasion, eliminating a great variety of pathogens and contributing with the activation of the adaptive immune response. The components of innate immunity include physical and chemical barriers, humoral and cell-mediated components, which are present in all jawed vertebrates. The understanding of innate defence mechanisms in non-mammalian vertebrates is the key to comprehend the general picture of vertebrate innate immunity and its evolutionary history. This is also essential for the identification of new molecules with applications in immunopharmacology and immunotherapy. In this review, we describe and discuss the main elements of vertebrate innate immunity, presenting core findings in this field and identifying areas that need further investigation. © 2016 John Wiley & Sons Ltd.

Assisted techniques for vertebral cementoplasty: Why should we do it?

Energy Technology Data Exchange (ETDEWEB)

Muto, M., E-mail: mutomar@tiscali.it [Department of Diagnostic Imaging, Section of Neuroradiology—“A. Cardarelli” Hospital, Naples (Italy); Marcia, S. [Section of Radiology—Santissima Trinità Hospital, Cagliari (Italy); Guarnieri, G. [Department of Diagnostic Imaging, Section of Neuroradiology—“A. Cardarelli” Hospital, Naples (Italy); Pereira, V. [Unit of Interventional Neuroradiology–HUG, Geneva (Switzerland)

2015-05-15

Assisted techniques (AT) for vertebral cementoplasty include multiple mini-invasive percutaneous systems in which vertebral augmentation is obtained through mechanical devices with the aim to reach the best vertebral height restoration. As an evolution of the vertebroplasty, the rationale of the AT-treatment is to combine the analgesic and stability effect of cement injection with the restoration of a physiological height for the collapsed vertebral body. Reduction of the vertebral body kyphotic deformity, considering the target of normal spine biomechanics, could improve all systemic potential complications evident in patient with vertebral compression fracture (VCF). Main indications for AT are related to fractures in fragile vertebral osseous matrix and non-osteoporotic vertebral lesions due to spine metastasis or trauma. Many companies developed different systems for AT having the same target but different working cannula, different vertebral height restoration system and costs. Aim of this review is to discuss about vertebral cementoplasty procedures and techniques, considering patient inclusion and exclusion criteria as well as all related minor and/or major interventional complications.

Assisted techniques for vertebral cementoplasty: Why should we do it?

International Nuclear Information System (INIS)

Muto, M.; Marcia, S.; Guarnieri, G.; Pereira, V.

2015-01-01

Assisted techniques (AT) for vertebral cementoplasty include multiple mini-invasive percutaneous systems in which vertebral augmentation is obtained through mechanical devices with the aim to reach the best vertebral height restoration. As an evolution of the vertebroplasty, the rationale of the AT-treatment is to combine the analgesic and stability effect of cement injection with the restoration of a physiological height for the collapsed vertebral body. Reduction of the vertebral body kyphotic deformity, considering the target of normal spine biomechanics, could improve all systemic potential complications evident in patient with vertebral compression fracture (VCF). Main indications for AT are related to fractures in fragile vertebral osseous matrix and non-osteoporotic vertebral lesions due to spine metastasis or trauma. Many companies developed different systems for AT having the same target but different working cannula, different vertebral height restoration system and costs. Aim of this review is to discuss about vertebral cementoplasty procedures and techniques, considering patient inclusion and exclusion criteria as well as all related minor and/or major interventional complications

Posterior-only approach for lumbar vertebral column resection and expandable cage reconstruction for spinal metastases.

Science.gov (United States)

Jandial, Rahul; Kelly, Brandon; Chen, Mike Yue

2013-07-01

The increasing incidence of spinal metastasis, a result of improved systemic therapies for cancer, has spurred a search for an alternative method for the surgical treatment of lumbar metastases. The authors report a single-stage posterior-only approach for resecting any pathological lumbar vertebral segment and reconstructing with a medium to large expandable cage while preserving all neurological structures. The authors conducted a retrospective consecutive case review of 11 patients (5 women, 6 men) with spinal metastases treated at 1 institution with single-stage posterior-only vertebral column resection and reconstruction with an expandable cage and pedicle screw fixation. For all patients, the indications for operative intervention were spinal cord compression, cauda equina compression, and/or spinal instability. Neurological status was classified according to the American Spinal Injury Association impairment scale, and functional outcomes were analyzed by using a visual analog scale for pain. For all patients, a circumferential vertebral column resection was achieved, and full decompression was performed with a posterior-only approach. Each cage was augmented by posterior pedicle screw fixation extending 2 levels above and below the resected level. No patient required a separate anterior procedure. Average estimated blood loss and duration of each surgery were 1618 ml (range 900-4000 ml) and 6.6 hours (range 4.5-9 hours), respectively. The mean follow-up time was 14 months (range 10-24 months). The median survival time after surgery was 17.7 months. Delayed hardware failure occurred for 1 patient. Preoperatively, 2 patients had intractable pain with intact lower-extremity strength and 8 patients had severe intractable pain, lower-extremity paresis, and were unable to walk; 4 of whom regained the ability to walk after surgery. Two patients who were paraplegic before decompression recovered substantial function but remained wheelchair bound, and 2 patients

Duplication of the Left Vertebral Artery Origin: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Shin, Sang Wook; Park, Dong Woo; Park, Choong Ki; Lee, Young Jun [Dept. of Radiology, College of Medicine, Hanyang University, Hanyang University Guri Hospital, Guri (Korea, Republic of)

2013-01-15

Duplication of vertebral arteries is a very rare but clinically important condition. A duplicated vertebral artery origin can influence hemodynamics, pathogenesis of vascular lesions and treatment options. In cases of vertebral artery duplication, the vertebral arteries generally enter the transverse foramen higher up than normal. Awareness of these vertebral artery variants before procedures, such as neurointervention or surgery, may be beneficial. Here, we describe a case of a 51-year-old female patient with left vertebral artery duplication which was detected incidentally.

Duplication of the Left Vertebral Artery Origin: A Case Report

International Nuclear Information System (INIS)

Shin, Sang Wook; Park, Dong Woo; Park, Choong Ki; Lee, Young Jun

2013-01-01

Duplication of vertebral arteries is a very rare but clinically important condition. A duplicated vertebral artery origin can influence hemodynamics, pathogenesis of vascular lesions and treatment options. In cases of vertebral artery duplication, the vertebral arteries generally enter the transverse foramen higher up than normal. Awareness of these vertebral artery variants before procedures, such as neurointervention or surgery, may be beneficial. Here, we describe a case of a 51-year-old female patient with left vertebral artery duplication which was detected incidentally.

Comparative micro computed tomography study of a vertebral body

Science.gov (United States)

Drews, Susanne; Beckmann, Felix; Herzen, Julia; Brunke, Oliver; Salmon, Phil; Friess, Sebastian; Laib, Andres; Koller, Bruno; Hemberger, Thomas; Müller-Gerbl, Magdalena; Müller, Bert

2008-08-01

Investigations of bony tissues are often performed using micro computed tomography based on X-rays, since the calcium distribution leads to superior contrast. Osteoporotic bone, for example, can be well compared with healthy one with respect to density and morphology. Degenerative and rheumatoid diseases usually start, however, at the bone-cartilage-interface, which is hardly accessible. The direct influence on the bone itself becomes only visible at later stage. For the development of suitable therapies against degenerative cartilage damages the exact three-dimensional description of the bone-cartilage interface is vital, as demonstrated for transplanted cartilage-cells or bone-cartilage-constructs in animal models. So far, the morphological characterization was restricted to magnetic resonance imaging (MRI) with poor spatial resolution or to time-consuming histological sectioning with appropriate spatial resolution only in two rather arbitrarily chosen directions. Therefore, one should develop μCT to extract the features of low absorbing cartilage. The morphology and the volume of the inter-vertebral cartilage disc of lumbar motion segments have been determined for one PMMA embedded specimen. Tomograms were recorded using nanotom® (Phoenix|x-ray, Wunstorf, Germany), μCT 35TM (Scanco Medical, Brütisellen, Switzerland), 1172TM and 1174TM (both Skyscan, Kontich, Belgium), as well as using the SRμCT at HASYLAB/DESY. Conventional and SRμCT can provide the morphology and the volume of cartilage between bones. Increasing the acquisition time, the signal-to-noise ratio becomes better and better but the prominent artifacts in conventional μCT as the result of inhomogeneously distributed bony tissue prevents the exact segmentation of cartilage. SRμCT allows segmenting the cartilage but requires long periods of expensive beam-time to obtain reasonable contrast.

Automatic vertebral identification using surface-based registration

Science.gov (United States)

Herring, Jeannette L.; Dawant, Benoit M.

2000-06-01

This work introduces an enhancement to currently existing methods of intra-operative vertebral registration by allowing the portion of the spinal column surface that correctly matches a set of physical vertebral points to be automatically selected from several possible choices. Automatic selection is made possible by the shape variations that exist among lumbar vertebrae. In our experiments, we register vertebral points representing physical space to spinal column surfaces extracted from computed tomography images. The vertebral points are taken from the posterior elements of a single vertebra to represent the region of surgical interest. The surface is extracted using an improved version of the fully automatic marching cubes algorithm, which results in a triangulated surface that contains multiple vertebrae. We find the correct portion of the surface by registering the set of physical points to multiple surface areas, including all vertebral surfaces that potentially match the physical point set. We then compute the standard deviation of the surface error for the set of points registered to each vertebral surface that is a possible match, and the registration that corresponds to the lowest standard deviation designates the correct match. We have performed our current experiments on two plastic spine phantoms and one patient.

Observer agreement in pediatric semiquantitative vertebral fracture diagnosis

Energy Technology Data Exchange (ETDEWEB)

Siminoski, Kerry [University of Alberta, Department of Radiology and Diagnostic Imaging and Division of Endocrinology and Metabolism, Department of Medicine, Edmonton (Canada); Lentle, Brian [University of British Columbia, Department of Radiology, Vancouver (Canada); BC Children' s Hospital, Department of Radiology, Vancouver (Canada); Matzinger, Mary Ann; Shenouda, Nazih [University of Ottawa, Department of Diagnostic Imaging, Ottawa (Canada); Children' s Hospital of Eastern Ontario, Department of Medical Imaging, Ottawa (Canada); Ward, Leanne M. [University of Ottawa, Department of Pediatrics, Children' s Hospital of Eastern Ontario, Ottawa (Canada); Children' s Hospital of Eastern Ontario, Research Institute, Ottawa (Canada); Collaboration: The Canadian STOPP Consortium

2014-04-15

The Genant semiquantitative (GSQ) method has been a standard procedure for diagnosis of vertebral fractures in adults but has only recently been shown to be of clinical utility in children. Observer agreement using the GSQ method in this age group has not been described. To evaluate observer agreement on vertebral readability and vertebral fracture diagnosis using the GSQ method in pediatric vertebral morphometry. Spine radiographs of 186 children with acute lymphoblastic leukemia were evaluated independently by three radiologists using the same GSQ methodology as in adults. A subset of 100 radiographs was evaluated on two occasions. An average of 4.7% of vertebrae were unreadable for the three radiologists. Intraobserver Cohen's kappa (κ) on readability ranged from 0.434 to 0.648 at the vertebral level and from 0.416 to 0.611 at the patient level, while interobserver κ for readability had a range of 0.330 to 0.504 at the vertebral level and 0.295 to 0.467 at the patient level. Intraobserver κ for the presence of vertebral fracture had a range of 0.529 to 0.726 at the vertebral level and was 0.528 to 0.767 at the patient level. Interobserver κ for fracture at the vertebral level ranged from 0.455 to 0.548 and from 0.433 to 0.486 at the patient level. Most κ values for both intra- and interobserver agreement in applying the GSQ method to pediatric spine radiographs were in the moderate to substantial range, comparable to the performance of the technique in adult studies. The GSQ method should be considered for use in pediatric research and clinical practice. (orig.)

Observer agreement in pediatric semiquantitative vertebral fracture diagnosis

International Nuclear Information System (INIS)

Siminoski, Kerry; Lentle, Brian; Matzinger, Mary Ann; Shenouda, Nazih; Ward, Leanne M.

2014-01-01

The Genant semiquantitative (GSQ) method has been a standard procedure for diagnosis of vertebral fractures in adults but has only recently been shown to be of clinical utility in children. Observer agreement using the GSQ method in this age group has not been described. To evaluate observer agreement on vertebral readability and vertebral fracture diagnosis using the GSQ method in pediatric vertebral morphometry. Spine radiographs of 186 children with acute lymphoblastic leukemia were evaluated independently by three radiologists using the same GSQ methodology as in adults. A subset of 100 radiographs was evaluated on two occasions. An average of 4.7% of vertebrae were unreadable for the three radiologists. Intraobserver Cohen's kappa (κ) on readability ranged from 0.434 to 0.648 at the vertebral level and from 0.416 to 0.611 at the patient level, while interobserver κ for readability had a range of 0.330 to 0.504 at the vertebral level and 0.295 to 0.467 at the patient level. Intraobserver κ for the presence of vertebral fracture had a range of 0.529 to 0.726 at the vertebral level and was 0.528 to 0.767 at the patient level. Interobserver κ for fracture at the vertebral level ranged from 0.455 to 0.548 and from 0.433 to 0.486 at the patient level. Most κ values for both intra- and interobserver agreement in applying the GSQ method to pediatric spine radiographs were in the moderate to substantial range, comparable to the performance of the technique in adult studies. The GSQ method should be considered for use in pediatric research and clinical practice. (orig.)

Developing a Procedure for Segmenting Meshed Heat Networks of Heat Supply Systems without Outflows

Science.gov (United States)

Tokarev, V. V.

2018-06-01

The heat supply systems of cities have, as a rule, a ring structure with the possibility of redistributing the flows. Despite the fact that a ring structure is more reliable than a radial one, the operators of heat networks prefer to use them in normal modes according to the scheme without overflows of the heat carrier between the heat mains. With such a scheme, it is easier to adjust the networks and to detect and locate faults in them. The article proposes a formulation of the heat network segmenting problem. The problem is set in terms of optimization with the heat supply system's excessive hydraulic power used as the optimization criterion. The heat supply system computer model has a hierarchically interconnected multilevel structure. Since iterative calculations are only carried out for the level of trunk heat networks, decomposing the entire system into levels allows the dimensionality of the solved subproblems to be reduced by an order of magnitude. An attempt to solve the problem by fully enumerating possible segmentation versions does not seem to be feasible for systems of really existing sizes. The article suggests a procedure for searching rational segmentation of heat supply networks with limiting the search to versions of dividing the system into segments near the flow convergence nodes with subsequent refining of the solution. The refinement is performed in two stages according to the total excess hydraulic power criterion. At the first stage, the loads are redistributed among the sources. After that, the heat networks are divided into independent fragments, and the possibility of increasing the excess hydraulic power in the obtained fragments is checked by shifting the division places inside a fragment. The proposed procedure has been approbated taking as an example a municipal heat supply system involving six heat mains fed from a common source, 24 loops within the feeding mains plane, and more than 5000 consumers. Application of the proposed

Vascular complications of prosthetic inter-vertebral discs

OpenAIRE

Daly, Kevin J.; Ross, E. Raymond S.; Norris, Heather; McCollum, Charles N.

2006-01-01

Five consecutive cases of prosthetic inter-vertebral disc displacement with severe vascular complications on revisional surgery are described. The objective of this case report is to warn spinal surgeons that major vascular complications are likely with anterior displacement of inter-vertebral discs. We have not been able to find a previous report on vascular complications associated with anterior displacement of prosthetic inter-vertebral discs. In all five patients the prosthetic disc had e...

Non-invasive approach towards the in vivo estimation of 3D inter-vertebral movements: methods and preliminary results.

Science.gov (United States)

Cerveri, P; Pedotti, A; Ferrigno, G

2004-12-01

A kinematical model of the lower spine was designed and used to obtain a robust estimation of the vertebral rotations during torso movements from skin-surface markers recorded by video-cameras. Markers were placed in correspondence of the anatomical landmarks of the pelvic bone and vertebral spinous and transverse processes, and acquired during flexion, lateral bending and axial motions. In the model calibration stage, a motion-based approach was used to compute the rotation axes and centres of the functional segmental units. Markers were mirrored into virtual points located on the model surface, expressed in the local reference system of coordinates. The spine motion assessment was solved into the domain of extended Kalman filters: at each frame of the acquisition, the model pose was updated by minimizing the distances between the measured 2D marker projections on the cameras and the corresponding back-projections of virtual points located on the model surface. The novelty of the proposed technique rests on the fact that the varying location of the rotation centres of the functional segmental units can be tracked directly during motion computation. In addition, we show how the effects of skin artefacts on orientation data can be taken into account. As a result, the kinematical estimation of simulated motions shows that orientation artefacts were reduced by a factor of at least 50%. Preliminary experiments on real motion confirmed the reliability of the proposed method with results in agreement with classical studies in literature.

Constrained vertebrate evolution by pleiotropic genes.

Science.gov (United States)

Hu, Haiyang; Uesaka, Masahiro; Guo, Song; Shimai, Kotaro; Lu, Tsai-Ming; Li, Fang; Fujimoto, Satoko; Ishikawa, Masato; Liu, Shiping; Sasagawa, Yohei; Zhang, Guojie; Kuratani, Shigeru; Yu, Jr-Kai; Kusakabe, Takehiro G; Khaitovich, Philipp; Irie, Naoki

2017-11-01

Despite morphological diversification of chordates over 550 million years of evolution, their shared basic anatomical pattern (or 'bodyplan') remains conserved by unknown mechanisms. The developmental hourglass model attributes this to phylum-wide conserved, constrained organogenesis stages that pattern the bodyplan (the phylotype hypothesis); however, there has been no quantitative testing of this idea with a phylum-wide comparison of species. Here, based on data from early-to-late embryonic transcriptomes collected from eight chordates, we suggest that the phylotype hypothesis would be better applied to vertebrates than chordates. Furthermore, we found that vertebrates' conserved mid-embryonic developmental programmes are intensively recruited to other developmental processes, and the degree of the recruitment positively correlates with their evolutionary conservation and essentiality for normal development. Thus, we propose that the intensively recruited genetic system during vertebrates' organogenesis period imposed constraints on its diversification through pleiotropic constraints, which ultimately led to the common anatomical pattern observed in vertebrates.

ARIES segmented gamma-ray scanner user manual

International Nuclear Information System (INIS)

Biddle, R.S.; Sheppard, G.A.; Schneider, C.M.

1998-01-01

The segmented gamma-ray scatter (SGS) designated as Win SGS at the Los Alamos Plutonium Facility has been installed and is intended for use in quantifying the radioisotope content of DOE-STD-3013-96 equivalent containers. The SGS features new software written in C and a new user interface that runs under Microsoft Windows trademark. The operation of the ARIES Segmented Gamma-ray Scanner is documented in this manual. It covers user instructions as well as hardware and software details. Additional information is found in the documentation for the commercially available components and modules that compose the SGS. The objective of the ARIES project is to demonstrate technology to dismantle plutonium pits from excess nuclear weapons, convert the plutonium to a metal ingot or an oxide powder, package the metal or oxide, and verify the contents of the package by nondestructive assay

Modulación del crecimiento vertebral mediante electrocoagulación hemicircunferencial vertebral asistida

OpenAIRE

Caballero García, Alberto

2011-01-01

Nuestro trabajo está basado en la posibilidad de controlar el desarrollo asimétrico de los cartílagos de crecimiento vertebral, mediante la realización de una fisiodesis hemivertebral, con electrocoagulación, videoasistida por toracoscópica. Se realizará en cinco niveles torácicos, con un abordaje anterior mínimamente invasivo. Por lo tanto, planteamos como hipótesis de trabajo que La destrucción de las fisis de crecimiento vertebral mediante electrocoagulación, videoasistida por vía toracosc...

SpineAnalyzer™ is an accurate and precise method of vertebral fracture detection and classification on dual-energy lateral vertebral assessment scans

International Nuclear Information System (INIS)

Birch, C.; Knapp, K.; Hopkins, S.; Gallimore, S.; Rock, B.

2015-01-01

Osteoporotic fractures of the spine are associated with significant morbidity, are highly predictive of hip fractures, but frequently do not present clinically. When there is a low to moderate clinical suspicion of vertebral fracture, which would not justify acquisition of a radiograph, vertebral fracture assessment (VFA) using Dual-energy X-ray Absorptiometry (DXA) offers a low-dose opportunity for diagnosis. Different approaches to the classification of vertebral fractures have been documented. The aim of this study was to measure the precision and accuracy of SpineAnalyzer™, a quantitative morphometry software program. Lateral vertebral assessment images of 64 men were analysed using SpineAnalyzer™ and standard GE Lunar software. The images were also analysed by two expert readers using a semi-quantitative approach. Agreement between groups ranged from 95.99% to 98.60%. The intra-rater precision for the application of SpineAnalyzer™ to vertebrae was poor in the upper thoracic regions, but good elsewhere. SpineAnalyzer™ is a reproducible and accurate method for measuring vertebral height and quantifying vertebral fractures from VFA scans. - Highlights: • Vertebral fracture assessment (VFA) using Dual-energy X-ray Absorptiometry (DXA) offers a low-dose opportunity for diagnosis. • Agreement between VFA software (SpineAnalyzer™) and expert readers is high. • Intra-rater precision of SpineAnalyzer™ applied to upper thoracic vertebrae is poor, but good elsewhere. • SpineAnalyzer™ is reproducible and accurate for vertebral height measurement and fracture quantification from VFA scans

Influence of physical activity on vertebral strength during late adolescence.

Science.gov (United States)

Junno, Juho-Antti; Paananen, Markus; Karppinen, Jaro; Tammelin, Tuija; Niinimäki, Jaakko; Lammentausta, Eveliina; Niskanen, Markku; Nieminen, Miika T; Järvelin, Marjo-Riitta; Takatalo, Jani; Tervonen, Osmo; Tuukkanen, Juha

2013-02-01

Reduced vertebral strength is a clear risk factor for vertebral fractures. Men and women with vertebral fractures often have reduced vertebral size and bone mineral density (BMD). Vertebral strength is controlled by both genetic and developmental factors. Malnutrition and low levels of physical activity are commonly considered to result in reduced bone size during growth. Several studies have also demonstrated the general relationship between BMD and physical activity in the appendicular skeleton. In this study, we wanted to clarify the role of physical activity on vertebral bodies. Vertebral dimensions appear to generally be less pliant than long bones when lifetime changes occur. We wanted to explore the association between physical activity during late adolescence and vertebral strength parameters such as cross-sectional size and BMD. The association between physical activity and vertebral strength was explored by measuring vertebral strength parameters and defining the level of physical activity during adolescence. The study population consisted of 6,928 males and females who, at 15 to 16 and 19 years of age, responded to a mailed questionnaire inquiring about their physical activity. A total of 558 individuals at the mean age of 21 years underwent magnetic resonance imaging (MRI) scans. We measured the dimensions of the fourth lumbar vertebra from the MRI scans of the Northern Finland Birth Cohort 1986 and performed T2* relaxation time mapping, reflective of BMD. Vertebral strength was based on these two parameters. We analyzed the association of physical activity on vertebral strength using the analysis of variance. We observed no association between the level of physical activity during late adolescence and vertebral strength at 21 years. Copyright © 2013 Elsevier Inc. All rights reserved.

Rehabilitation in osteoporotic vertebral fractures

OpenAIRE

Pratelli, Elisa; Cinotti, Irene; Pasquetti, Pietro

2010-01-01

Vertebral fractures occur particularly in osteoporotic patients due to an increased bone fragility. Vertebral fractures influence the quality of life, mobility and mortality. Preventive training exercises and proprioception reeducation can be utilised for improving posture, balance and level of daily function and for decreasing pain. Quality of life is improved even beyond the active training period. This mini review provides information based on the literature for the rehabilitation of osteo...

CT and MRI characteristics of vertebral tuberculosis (34 cases)

International Nuclear Information System (INIS)

Lu Wenbing; Liao Qinghou; Wu Shiqiang; Huang Tao; Deng Yufang; Liu Jianming

2007-01-01

Objective: To explore CT and MRI characteristics of vertebral tuberculosis. Methods: 34 patients with vertebral tuberculosis proved by clinic or pathology were analyzed retrospectively. Of these patients, 20 were performed with CT examination and 24 with MRI, 10 with both CT and MRI. The results were compared mutually. Results: The CT features of vertebral tuberculosis were bone destruction, paraspinal abscess, spinal canal involvement. The MRI features of vertebral tuberculosis were bone destruction, intervertebral disc destruction, paraspinal abscess, spinal canal involvement, sub-ligamental spread. Conclusion: Vertebral tuberculosis showed multiple characteristics on CT and MRI. CT is useful in showing sequester and calcification, and MRI is useful in showing sub-ligamental spread, epidural and spinal cord involvement. Combining CT with and MRI is helpful for the diagnosis and differential diagnosis of vertebral tuberculosis. (authors)

Facultative parthenogenesis in vertebrates: reproductive error or chance?

Science.gov (United States)

Lampert, K P

2008-01-01

Parthenogenesis, the development of an embryo from a female gamete without any contribution of a male gamete, is very rare in vertebrates. Parthenogenetically reproducing species have, so far, only been found in the Squamate reptiles (lizards and snakes). Facultative parthenogenesis, switching between sexual and clonal reproduction, although quite common in invertebrates, e.g. Daphnia and aphids, seems to be even rarer in vertebrates. However, isolated cases of parthenogenetic development have been reported in all vertebrate groups. Facultative parthenogenesis in vertebrates has only been found in captive animals but might simply have been overlooked in natural populations. Even though its evolutionary impact is hard to determine and very likely varies depending on the ploidy restoration mechanisms and sex-determining mechanisms involved, facultative parthenogenesis is already discussed in conservation biology and medical research. To raise interest for facultative parthenogenesis especially in evolutionary biology, I summarize the current knowledge about facultative parthenogenesis in the different vertebrate groups, introduce mechanisms of diploid oocyte formation and discuss the genetic consequences and potential evolutionary impact of facultative parthenogenesis in vertebrates.

Ancient deuterostome origins of vertebrate brain signalling centres.

Science.gov (United States)

Pani, Ariel M; Mullarkey, Erin E; Aronowicz, Jochanan; Assimacopoulos, Stavroula; Grove, Elizabeth A; Lowe, Christopher J

2012-03-14

Neuroectodermal signalling centres induce and pattern many novel vertebrate brain structures but are absent, or divergent, in invertebrate chordates. This has led to the idea that signalling-centre genetic programs were first assembled in stem vertebrates and potentially drove morphological innovations of the brain. However, this scenario presumes that extant cephalochordates accurately represent ancestral chordate characters, which has not been tested using close chordate outgroups. Here we report that genetic programs homologous to three vertebrate signalling centres-the anterior neural ridge, zona limitans intrathalamica and isthmic organizer-are present in the hemichordate Saccoglossus kowalevskii. Fgf8/17/18 (a single gene homologous to vertebrate Fgf8, Fgf17 and Fgf18), sfrp1/5, hh and wnt1 are expressed in vertebrate-like arrangements in hemichordate ectoderm, and homologous genetic mechanisms regulate ectodermal patterning in both animals. We propose that these genetic programs were components of an unexpectedly complex, ancient genetic regulatory scaffold for deuterostome body patterning that degenerated in amphioxus and ascidians, but was retained to pattern divergent structures in hemichordates and vertebrates. © 2012 Macmillan Publishers Limited. All rights reserved

Varied overstrain injuries of the vertebral column conditioned by evolution

Energy Technology Data Exchange (ETDEWEB)

Kohlbach, W

1983-08-01

During physiological growth of the juvenile vertebral column, various stages of stability occur which are characterized by the condition of the marginal rim of the vertebral bodies. If the vertebral juvenile column is overstrained, these variations in stability results in a variety of damage to vertebral bodies and vertebral disks. One of these lesions corresponds to Scheuermann's disease (osteochondrosis of vertebral epiphyses in juveniles). Damage of the vertebral column due to overstrain can occur only if the overstrain is applied in upright position. Since Man alone can damage his vertebral column in upright position (as a result of his evolutionary development), Scheuermann's thesis is confirmed that Scheuermann's disease is confined to Man. Spondylolysis/spondylolisthesis is also a damage caused by overstrain. Here, too, the damage can occur only if the load is exercised in upright position, with the exception of a slanted positioning of the intervertebral components.

Varied overstrain injuries of the vertebral column conditioned by evolution

International Nuclear Information System (INIS)

Kohlbach, W.

1983-01-01

During physiological growth of the juvenile vertebral column, various stages of stability occur which are characterized by the condition of the marginal rim of the vertebral bodies. If the vertebral juvenile column is overstrained, these variations in stability results in a variety of damage to vertebral bodies and vertebral disks. One of these lesions corresponds to Scheuermann's disease (osteochondrosis of vertebral epiphyses in juveniles). Damage of the vertebral column due to overstrain can occur only if the overstrain is applied in upright position. Since Man alone can damage his vertebral column in upright position (as a result of his evolutionary development), Scheuermann's thesis is confirmed that Scheuermann's disease is confined to Man. Spondylolysis/spondylolisthesis is also a damage caused by overstrain. Here, too, the damage can occur only if the load is exercised in upright position, with the exception of a slanted positioning of the intervertebral components. (orig.) [de

The prevalence of radiographic vertebral fractures in Latin American countries: the Latin American Vertebral Osteoporosis Study (LAVOS).

Science.gov (United States)

Clark, P; Cons-Molina, F; Deleze, M; Ragi, S; Haddock, L; Zanchetta, J R; Jaller, J J; Palermo, L; Talavera, J O; Messina, D O; Morales-Torres, J; Salmeron, J; Navarrete, A; Suarez, E; Pérez, C M; Cummings, S R

2009-02-01

In the first population-based study of vertebral fractures in Latin America, we found a 11.18 (95% CI 9.23-13.4) prevalence of radiographically ascertained vertebral fractures in a random sample of 1,922 women from cities within five different countries. These figures are similar to findings from studies in Beijing, China, some regions of Europe, and slightly lower than those found in the USA using the same standardized methodology. We report the first study of radiographic vertebral fractures in Latin America. An age-stratified random sample of 1,922 women aged 50 years and older from Argentina, Brazil, Colombia, Mexico, and Puerto Rico were included. In all cases a standardized questionnaire and lateral X-rays of the lumbar and thoracic spine were obtained after informed consent. A standardized prevalence of 11.18 (95% CI 9.23-13.4) was found. The prevalence was similar in all five countries, increasing from 6.9% (95% CI 4.6-9.1) in women aged 50-59 years to 27.8% (95% CI 23.1-32.4) in those 80 years and older (p for trend < 0.001). Among different risk factors, self-reported height loss OR = 1.63 (95% CI: 1.18-2.25), and previous history of fracture OR = 1.52 (95% CI: 1.14-2.03) were significantly (p < 0.003 and p < 0.04 respectably) associated with the presence of radiographic vertebral fractures in the multivariate analysis. In the bivariate analyses HRT was associated with a 35% lower risk OR = 0.65 (95% CI: 0.46-0.93) and physical activity with a 27% lower risk of having a vertebral fracture OR = 0.73 (95% CI: 0.55-0.98), but were not statistically significant in multivariate analyses We conclude that radiographically ascertained vertebral fractures are common in Latin America. Health authorities in the region should be aware and consider implementing measures to prevent vertebral fractures.

Prevalence of thoracolumbar vertebral fractures on multidetector CT

International Nuclear Information System (INIS)

Bartalena, Tommaso; Giannelli, Giovanni; Rinaldi, Maria Francesca; Rimondi, Eugenio; Rinaldi, Giovanni; Sverzellati, Nicola; Gavelli, Giampaolo

2009-01-01

Objective: To evaluate the prevalence of osteoporotic vertebral fractures in patients undergoing multidetector computed tomography (MDCT) of the chest and/or abdomen. Materials and methods: 323 consecutive patients (196 males, 127 females) with a mean age of 62.6 years (range 20-88) who had undergone chest and/or abdominal MDCT were evaluated. Sagittal reformats of the spine obtained from thin section datasets were reviewed by two radiologists and assessed for vertebral fractures. Morphometric analysis using electronic calipers was performed on vertebral bodies which appeared abnormal upon visual inspection. A vertebral body height loss of 15% or more was considered a fracture and graded as mild (15-24%), moderate (25-49%) or severe (more than 50%). Official radiology reports were reviewed and whether the vertebral fractures had been reported or not was noted. Results: 31 out of 323 patients (9.5%) had at least 1 vertebral fracture and 7 of those patients had multiple fractures for a total of 41 fractures. Morphometric grading revealed 10 mild, 16 moderate and 15 severe fractures. Prevalence was higher in women (14.1%) than men (6.6%) and increased with patients age with a 17.1% prevalence in post-menopausal women. Only 6 out 41 vertebral fractures (14.6%) had been noted in the radiology final report while the remaining 35 (85.45) had not. Conclusion: although vertebral fractures represent frequent incidental findings on multidetector CT studies and may be easily identified on sagittal reformats, they are often underreported by radiologists, most likely because of unawareness of their clinical importance.

Coordination of fictive motor activity in the larval zebrafish is generated by non-segmental mechanisms.

Directory of Open Access Journals (Sweden)

Timothy D Wiggin

Full Text Available The cellular and network basis for most vertebrate locomotor central pattern generators (CPGs is incompletely characterized, but organizational models based on known CPG architectures have been proposed. Segmental models propose that each spinal segment contains a circuit that controls local coordination and sends longer projections to coordinate activity between segments. Unsegmented/continuous models propose that patterned motor output is driven by gradients of neurons and synapses that do not have segmental boundaries. We tested these ideas in the larval zebrafish, an animal that swims in discrete episodes, each of which is composed of coordinated motor bursts that progress rostrocaudally and alternate from side to side. We perturbed the spinal cord using spinal transections or strychnine application and measured the effect on fictive motor output. Spinal transections eliminated episode structure, and reduced both rostrocaudal and side-to-side coordination. Preparations with fewer intact segments were more severely affected, and preparations consisting of midbody and caudal segments were more severely affected than those consisting of rostral segments. In reduced preparations with the same number of intact spinal segments, side-to-side coordination was more severely disrupted than rostrocaudal coordination. Reducing glycine receptor signaling with strychnine reversibly disrupted both rostrocaudal and side-to-side coordination in spinalized larvae without disrupting episodic structure. Both spinal transection and strychnine decreased the stability of the motor rhythm, but this effect was not causal in reducing coordination. These results are inconsistent with a segmented model of the spinal cord and are better explained by a continuous model in which motor neuron coordination is controlled by segment-spanning microcircuits.

Reproducibility of central lumbar vertebral BMD

International Nuclear Information System (INIS)

Chan, F.; Pocock, N.; Griffiths, M.; Majerovic, Y.; Freund, J.

1997-01-01

Full text: Lumbar vertebral bone mineral density (BMD) using dual X-ray absorptiometry (DXA) has generally been calculated from a region of interest which includes the entire vertebral body. Although this region excludes part of the transverse processes, it does include the outer cortical shell of the vertebra. Recent software has been devised to calculate BMD in a central vertebral region of interest which excludes the outer cortical envelope. Theoretically this area may be more sensitive to detecting osteoporosis which affects trabecular bone to a greater extent than cortical bone. Apart from the sensitivity of BMD estimation, the reproducibility of any measurement is important owing to the slow rate of change of bone mass. We have evaluated the reproducibility of this new vertebral region of interest in 23 women who had duplicate lumbar spine DXA scans performed on the same day. The patients were repositioned between each measurement. Central vertebral analysis was performed for L2-L4 and the reproducibility of area, bone mineral content (BMC) and BMD calculated as the coefficient of variation; these values were compared with those from conventional analysis. Thus we have shown that the reproducibility of the central BMD is comparable to the conventional analysis which is essential if this technique is to provide any additional clinical data. The reasons for the decrease in reproducibility of the area and hence BMC requires further investigation

Varied overstrain injuries of the vertebral column conditioned by evolution

Energy Technology Data Exchange (ETDEWEB)

Kohlbach, W.

1983-08-01

During physiological growth of the juvenile vertebral column, various stages of stability occur which are characterized by the condition of the marginal rim of the vertebral bodies. If the vertebral juvenile column is overstrained, these variations in stability results in a variety of damage to vertebral bodies and vertebral disks. One of these lesions corresponds to Scheuermann's disease (osteochondrosis of vertebral epiphyses in juveniles). Damage of the vertebral column due to overstrain can occur only if the overstrain is applied in upright position. Since Man alone can damage his vertebral column in upright position (as a result of his evolutionary development), Scheuermann's thesis is confirmed that Scheuermann's disease is confined to Man. Spondylolysis/spondylolisthesis is also a damage caused by overstrain. Here, too, the damage can occur only if the load is exercised in upright position, with the exception of a slanted positioning of the intervertebral components.

High-altitude adaptations in vertebrate hemoglobins

DEFF Research Database (Denmark)

Weber, Roy E.

2007-01-01

Vertebrates at high altitude are subjected to hypoxic conditions that challenge aerobic metabolism. O2 transport from the respiratory surfaces to tissues requires matching between the O2 loading and unloading tensions and theO2-affinity of blood, which is an integrated function of hemoglobin......, birds and ectothermic vertebrates at high altitude....

The chick somitogenesis oscillator is arrested before all paraxial mesoderm is segmented into somites

Directory of Open Access Journals (Sweden)

McGrew Michael J

2010-02-01

Full Text Available Abstract Background Somitogenesis is the earliest sign of segmentation in the developing vertebrate embryo. This process starts very early, soon after gastrulation has initiated and proceeds in an anterior-to-posterior direction during body axis elongation. It is widely accepted that somitogenesis is controlled by a molecular oscillator with the same periodicity as somite formation. This periodic mechanism is repeated a specific number of times until the embryo acquires a defined specie-specific final number of somites at the end of the process of axis elongation. This final number of somites varies widely between vertebrate species. How termination of the process of somitogenesis is determined is still unknown. Results Here we show that during development there is an imbalance between the speed of somite formation and growth of the presomitic mesoderm (PSM/tail bud. This decrease in the PSM size of the chick embryo is not due to an acceleration of the speed of somite formation because it remains constant until the last stages of somitogenesis, when it slows down. When the chick embryo reaches its final number of somites at stage HH 24-25 there is still some remaining unsegmented PSM in which expression of components of the somitogenesis oscillator is no longer dynamic. Finally, we identify a change in expression of retinoic acid regulating factors in the tail bud at late stages of somitogenesis, such that in the chick embryo there is a pronounced onset of Raldh2 expression while in the mouse embryo the expression of the RA inhibitor Cyp26A1 is downregulated. Conclusions Our results show that the chick somitogenesis oscillator is arrested before all paraxial mesoderm is segmented into somites. In addition, endogenous retinoic acid is probably also involved in the termination of the process of segmentation, and in tail growth in general.

Vertebral body osteomyelitis in the horse

International Nuclear Information System (INIS)

Markel, M.D.; Madigan, J.E.; Lichtensteiger, C.A.; Large, S.M.; Hornof, W.J.

1986-01-01

The clinical signs, laboratory data, results of nuclear scintigraphy and radiographic examination of five horses with vertebral body osteomyelitis are described together with response to treatment. Three horses were less than five months of age. Four horses demonstrated hindlimb paresis and in three a focus of pain in the thoracolumbar region could be identified. An umbilical abscess, a caudal lobe lung abscess and a patent urachus were considered primary niduses of infection in each of three horses. Leucocytosis, neutrophilia, anaemia and elevated fibrinogen were the most consistent laboratory abnormalities. Nuclear scintigraphy was performed in three horses and identified the site of the vertebral lesion which was subsequently evaluated radiographically. In the other two horses radiographic examination in the region of areas of focal pain identified a lesion. Radiographic abnormalities included compression fractures of vertebral bodies (two), proliferative new bone (three) and soft tissue swelling ventral to a vertebral body (one). Two horses, including one with a compression fracture of the second lumbar vertebra, received parenteral antimicrobial therapy for 40 and 74 days, respectively. When re-examined six months later they showed no neurological abnormalities. The other three horses failed to respond to antimicrobial treatment and were humanely destroyed. The horse with a lung abscess also had an abscess cranial to the right tuber coxae which extended into the vertebral bodies of the third and fourth lumbar vertebrae from which Streptococcus zooepidemicus was cultured. A horse with proliferative new bone on the ventral aspect of the fifth and sixth thoracic vertebrae had a mediastinal mass associated with these vertebrae and fungal granulomas, from which Aspergillus species was cultured, in the heart and aorta, trachea, spleen and kidney. The horse with a patent urachus and soft tissue swelling ventral to the vertebral body of the 12th thoracic vertebra

Quantitative characterization of metastatic disease in the spine. Part I. Semiautomated segmentation using atlas-based deformable registration and the level set method

International Nuclear Information System (INIS)

Hardisty, M.; Gordon, L.; Agarwal, P.; Skrinskas, T.; Whyne, C.

2007-01-01

Quantitative assessment of metastatic disease in bone is often considered immeasurable and, as such, patients with skeletal metastases are often excluded from clinical trials. In order to effectively quantify the impact of metastatic tumor involvement in the spine, accurate segmentation of the vertebra is required. Manual segmentation can be accurate but involves extensive and time-consuming user interaction. Potential solutions to automating segmentation of metastatically involved vertebrae are demons deformable image registration and level set methods. The purpose of this study was to develop a semiautomated method to accurately segment tumor-bearing vertebrae using the aforementioned techniques. By maintaining morphology of an atlas, the demons-level set composite algorithm was able to accurately differentiate between trans-cortical tumors and surrounding soft tissue of identical intensity. The algorithm successfully segmented both the vertebral body and trabecular centrum of tumor-involved and healthy vertebrae. This work validates our approach as equivalent in accuracy to an experienced user

Osteomielitis vertebral piógena Pyogenic vertebral osteomyelitis

Directory of Open Access Journals (Sweden)

Pedro P. Perrotti

2009-10-01

Full Text Available La osteomielitis vertebral piógena (OVP es una localización poco frecuente (2-7% Se confirma con el aislamiento de un microorganismo de una vértebra, disco intervertebral, absceso epidural o paravertebral. Se describe una serie de casos por la infrecuente presentación de esta enfermedad, que puede ser consulta inicial en los servicios de clínica médica y por su sintomatología inespecífica que supone una dificultad diagnóstica. Tanto la columna lumbar como la dorsal fueron los sitios más afectados. El dolor dorsolumbar y la paraparesia fueron los síntomas más frecuentes de presentación. En ocho pacientes se aislaron Staphylococcus aureus, en uno Escherichia coli y en el restante Haemophylus sp. Se observó leucocitosis sólo en tres pacientes, y en dos velocidad de sedimentación globular mayor de 100 mm/h. Los diez pacientes presentaron imágenes características de osteomielitis vertebral piógena en la resonancia nuclear magnética. Dentro de las complicaciones, los abscesos paravertebrales y epidurales fueron los más frecuentes (en cinco enfermos. Además, un paciente presentó empiema pleural. De los diez pacientes de esta serie, siete recibieron inicialmente tratamiento médico empírico y luego específico para el germen aislado. En los restantes el tratamiento fue guiado de acuerdo al antibiograma. A dos enfermos fue necesario realizarles laminectomía descompresiva por compromiso de partes blandas y a otros dos estabilización quirúrgica por inestabilidad espinal, observándose buena evolución en todos los casos. Esta serie demuestra que, ante un paciente con dolor dorsolumbar y síntomas neurológicos se deberá tener en cuenta esta entidad para evitar un retraso en el tratamiento.Pyogenic osteomyelitis seldom affects the spine (2-7%. It is diagnosed by the isolation of a bacterial agent in the vertebral body, the intervertebral disks or from paravertebral or epidural abscesses. We report a retrospective study of ten

VerSeDa: vertebrate secretome database.

Science.gov (United States)

Cortazar, Ana R; Oguiza, José A; Aransay, Ana M; Lavín, José L

2017-01-01

Based on the current tools, de novo secretome (full set of proteins secreted by an organism) prediction is a time consuming bioinformatic task that requires a multifactorial analysis in order to obtain reliable in silico predictions. Hence, to accelerate this process and offer researchers a reliable repository where secretome information can be obtained for vertebrates and model organisms, we have developed VerSeDa (Vertebrate Secretome Database). This freely available database stores information about proteins that are predicted to be secreted through the classical and non-classical mechanisms, for the wide range of vertebrate species deposited at the NCBI, UCSC and ENSEMBL sites. To our knowledge, VerSeDa is the only state-of-the-art database designed to store secretome data from multiple vertebrate genomes, thus, saving an important amount of time spent in the prediction of protein features that can be retrieved from this repository directly. VerSeDa is freely available at http://genomics.cicbiogune.es/VerSeDa/index.php. © The Author(s) 2017. Published by Oxford University Press.

Gut Melatonin in Vertebrates: Chronobiology and Physiology

Directory of Open Access Journals (Sweden)

Dr. Saumen Kumar Maitra

2015-07-01

Full Text Available Melatonin, following discovery in the bovine pineal gland, has been detected in several extra-pineal sources including gastrointestinal tract or gut. Arylalkylamine N-acetyltransferase (AANAT is the key regulator of its biosynthesis. Melatonin in pineal is rhythmically produced with a nocturnal peak in synchronization with environmental light-dark cycle. A recent study on carp reported first that melatonin levels and intensity of a ~23kDa AANAT protein in each gut segment also exhibit significant daily variations but, unlike pineal, show a peak at midday in all seasons. Extensive experimental studies ruled out direct role of light-dark conditions in determining temporal pattern of gut melatoninergic system in carp, and opened up possible role of environmental non-photic cue(s as its synchronizer. Based on mammalian findings, physiological significance of gut derived melatonin also appears unique because its actions at local levels sharing paracrine and/or autocrine functions have been emphasized. The purpose of this mini-review is to summarize existing data on the chronobiology and physiology of gut melatonin and to emphasize their relation with the same hormone derived in the pineal in vertebrates including fish.

Kyphoplasty for severe osteoporotic vertebral compression fractures

International Nuclear Information System (INIS)

Bao Zhaohua; Wang Genlin; Yang Huilin; Meng Bin; Chen Kangwu; Jiang Weimin

2010-01-01

Objective: To evaluate the clininal efficacy of kyphoplasty for severe osteoporotic vertebral compression fractures. Methods: Forty-five patients with severe osteoporotic compressive fractures were treated by kyphoplasty from Jan 2005 to Jan 2009. The compressive rate of the fractured vertebral bodies was more than 75%. According to the morphology of the vertebral compression fracture bodies the unilateral or bilateral balloon kyphoplasty were selected. The anterior vertebral height was measured on a standing lateral radiograph at pre-operative, post-operative (one day after operation) and final follow-up time. A visual analog scale(VAS) and the Oswestry disability index (ODI) were chosen to evaluate pain status and functional activity. Results: The mean follow-up was for 21.7 months (in range from 18 to 48 months). The anterior vertebral body height of fracture vertebra was restored from preoperative (18.7 ± 3.1)% to postoperative (51.4 ± 2.3)%, the follow-up period (50.2 ± 2.7)%. There was a significant improvement between preoperative and postoperative values (P 0.05). The VAS was 8.1 ± 1.4 at preoperative, 2.6 ± 0.9 at postoperative, 2.1 ± 0.5 at final follow-up time; and the ODI was preoperative 91.1 ± 2.3, postoperative 30.7 ± 7.1, follow-up period 26.1 ± 5.1. There was statistically significant improvement in the VAS and ODI in the post-operative assessment compared with the pre-operative assessment (P 0.05). Asymptomatic cement leakage occurred in three cases. New vertebral fracture occurred in one case. Conclusion: The study suggests that balloon kyphoplasty is a safe and effective procedure in the treatment of severe osteoporotic vertebral compression fractures. (authors)

The pre-vertebrate origins of neurogenic placodes.

Science.gov (United States)

Abitua, Philip Barron; Gainous, T Blair; Kaczmarczyk, Angela N; Winchell, Christopher J; Hudson, Clare; Kamata, Kaori; Nakagawa, Masashi; Tsuda, Motoyuki; Kusakabe, Takehiro G; Levine, Michael

2015-08-27

The sudden appearance of the neural crest and neurogenic placodes in early branching vertebrates has puzzled biologists for over a century. These embryonic tissues contribute to the development of the cranium and associated sensory organs, which were crucial for the evolution of the vertebrate "new head". A previous study suggests that rudimentary neural crest cells existed in ancestral chordates. However, the evolutionary origins of neurogenic placodes have remained obscure owing to a paucity of embryonic data from tunicates, the closest living relatives to those early vertebrates. Here we show that the tunicate Ciona intestinalis exhibits a proto-placodal ectoderm (PPE) that requires inhibition of bone morphogenetic protein (BMP) and expresses the key regulatory determinant Six1/2 and its co-factor Eya, a developmental process conserved across vertebrates. The Ciona PPE is shown to produce ciliated neurons that express genes for gonadotropin-releasing hormone (GnRH), a G-protein-coupled receptor for relaxin-3 (RXFP3) and a functional cyclic nucleotide-gated channel (CNGA), which suggests dual chemosensory and neurosecretory activities. These observations provide evidence that Ciona has a neurogenic proto-placode, which forms neurons that appear to be related to those derived from the olfactory placode and hypothalamic neurons of vertebrates. We discuss the possibility that the PPE-derived GnRH neurons of Ciona resemble an ancestral cell type, a progenitor to the complex neuronal circuit that integrates sensory information and neuroendocrine functions in vertebrates.

Segmentation and registration duality from echographic images by use of physiological and morphological knowledge

International Nuclear Information System (INIS)

Ionescu, G.

1998-01-01

Echographic imaging could potentially play a major role in the field of Computer Assisted Surgery (CAS). For doctors and surgeons to make full use of tool in planning and executing surgical operations, they also need user-friendly automatic software based on fast, precise and reliable algorithms. The main goal of this thesis is to take advantage of the segmentation/registration duality to extract the relevant information from echo graphical images. This information will allow the precise and automatic registration both of anatomical structures contained in the pre-operative model and of per-operative data contained in echographic images. The result of registration will be further to guide a computer-assisted tool. In the first part we propose different methods for filtering, segmentation and calibration of echographic images. The development of fast, precise and reliable algorithms is emphasized. The second part concerns the segmentation-registration duality and the corrections of elastic deformations of soft tissues. High-level segmentation algorithms for echographic images were developed. They are based on results of low -level segmentation, a priori anatomical knowledge as well as on information provided by the pre-operative model. The third part deals with detailed descriptions of applications and interpretation of results. The cases studied include: screwing inside the vertebral pedicles, ilio-sacral screwing, prostatic radiotherapy and puncture of pericardial effusion. Future developments for this approach are discussed. (author)

Vertebrate DNA in fecal samples from bonobos and gorillas: evidence for meat consumption or artefact?

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Michael Hofreiter

Full Text Available BACKGROUND: Deciphering the behavioral repertoire of great apes is a challenge for several reasons. First, due to their elusive behavior in dense forest environments, great ape populations are often difficult to observe. Second, members of the genus Pan are known to display a great variety in their behavioral repertoire; thus, observations from one population are not necessarily representative for other populations. For example, bonobos (Pan paniscus are generally believed to consume almost no vertebrate prey. However, recent observations show that at least some bonobo populations may consume vertebrate prey more commonly than previously believed. We investigated the extent of their meat consumption using PCR amplification of vertebrate mitochondrial DNA (mtDNA segments from DNA extracted from bonobo feces. As a control we also attempted PCR amplifications from gorilla feces, a species assumed to be strictly herbivorous. PRINCIPAL FINDINGS: We found evidence for consumption of a variety of mammalian species in about 16% of the samples investigated. Moreover, 40% of the positive DNA amplifications originated from arboreal monkeys. However, we also found duiker and monkey mtDNA in the gorilla feces, albeit in somewhat lower percentages. Notably, the DNA sequences isolated from the two ape species fit best to the species living in the respective regions. This result suggests that the sequences are of regional origin and do not represent laboratory contaminants. CONCLUSIONS: Our results allow at least three possible and mutually not exclusive conclusions. First, all results may represent contamination of the feces by vertebrate DNA from the local environment. Thus, studies investigating a species' diet from feces DNA may be unreliable due to the low copy number of DNA originating from diet items. Second, there is some inherent difference between the bonobo and gorilla feces, with only the later ones being contaminated. Third, similar to bonobos, for

Vertebrate DNA in fecal samples from bonobos and gorillas: evidence for meat consumption or artefact?

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Hofreiter, Michael; Kreuz, Eva; Eriksson, Jonas; Schubert, Grit; Hohmann, Gottfried

2010-02-25

Deciphering the behavioral repertoire of great apes is a challenge for several reasons. First, due to their elusive behavior in dense forest environments, great ape populations are often difficult to observe. Second, members of the genus Pan are known to display a great variety in their behavioral repertoire; thus, observations from one population are not necessarily representative for other populations. For example, bonobos (Pan paniscus) are generally believed to consume almost no vertebrate prey. However, recent observations show that at least some bonobo populations may consume vertebrate prey more commonly than previously believed. We investigated the extent of their meat consumption using PCR amplification of vertebrate mitochondrial DNA (mtDNA) segments from DNA extracted from bonobo feces. As a control we also attempted PCR amplifications from gorilla feces, a species assumed to be strictly herbivorous. We found evidence for consumption of a variety of mammalian species in about 16% of the samples investigated. Moreover, 40% of the positive DNA amplifications originated from arboreal monkeys. However, we also found duiker and monkey mtDNA in the gorilla feces, albeit in somewhat lower percentages. Notably, the DNA sequences isolated from the two ape species fit best to the species living in the respective regions. This result suggests that the sequences are of regional origin and do not represent laboratory contaminants. Our results allow at least three possible and mutually not exclusive conclusions. First, all results may represent contamination of the feces by vertebrate DNA from the local environment. Thus, studies investigating a species' diet from feces DNA may be unreliable due to the low copy number of DNA originating from diet items. Second, there is some inherent difference between the bonobo and gorilla feces, with only the later ones being contaminated. Third, similar to bonobos, for which the consumption of monkeys has only recently been

Vertebral Column Resection for Rigid Spinal Deformity.

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Saifi, Comron; Laratta, Joseph L; Petridis, Petros; Shillingford, Jamal N; Lehman, Ronald A; Lenke, Lawrence G

2017-05-01

Broad narrative review. To review the evolution, operative technique, outcomes, and complications associated with posterior vertebral column resection. A literature review of posterior vertebral column resection was performed. The authors' surgical technique is outlined in detail. The authors' experience and the literature regarding vertebral column resection are discussed at length. Treatment of severe, rigid coronal and/or sagittal malalignment with posterior vertebral column resection results in approximately 50-70% correction depending on the type of deformity. Surgical site infection rates range from 2.9% to 9.7%. Transient and permanent neurologic injury rates range from 0% to 13.8% and 0% to 6.3%, respectively. Although there are significant variations in EBL throughout the literature, it can be minimized by utilizing tranexamic acid intraoperatively. The ability to correct a rigid deformity in the spine relies on osteotomies. Each osteotomy is associated with a particular magnitude of correction at a single level. Posterior vertebral column resection is the most powerful posterior osteotomy method providing a successful correction of fixed complex deformities. Despite meticulous surgical technique and precision, this robust osteotomy technique can be associated with significant morbidity even in the most experienced hands.

Vertebrate Embryonic Cleavage Pattern Determination.

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Hasley, Andrew; Chavez, Shawn; Danilchik, Michael; Wühr, Martin; Pelegri, Francisco

2017-01-01

The pattern of the earliest cell divisions in a vertebrate embryo lays the groundwork for later developmental events such as gastrulation, organogenesis, and overall body plan establishment. Understanding these early cleavage patterns and the mechanisms that create them is thus crucial for the study of vertebrate development. This chapter describes the early cleavage stages for species representing ray-finned fish, amphibians, birds, reptiles, mammals, and proto-vertebrate ascidians and summarizes current understanding of the mechanisms that govern these patterns. The nearly universal influence of cell shape on orientation and positioning of spindles and cleavage furrows and the mechanisms that mediate this influence are discussed. We discuss in particular models of aster and spindle centering and orientation in large embryonic blastomeres that rely on asymmetric internal pulling forces generated by the cleavage furrow for the previous cell cycle. Also explored are mechanisms that integrate cell division given the limited supply of cellular building blocks in the egg and several-fold changes of cell size during early development, as well as cytoskeletal specializations specific to early blastomeres including processes leading to blastomere cohesion. Finally, we discuss evolutionary conclusions beginning to emerge from the contemporary analysis of the phylogenetic distributions of cleavage patterns. In sum, this chapter seeks to summarize our current understanding of vertebrate early embryonic cleavage patterns and their control and evolution.

Vertebral metastases: characteristic MRI findings due to epidural carcinomatous inflitration

International Nuclear Information System (INIS)

Hutzelmann, A.; Palmie, S.; Freund, M.

1997-01-01

Purpose: In cases of lumbar vertebral metastasis associated with anterior epidural carcinomatous infiltration, we have observed that infiltrations tend to respect the midline. This study led to the systematic recognition of these phenomena in vertebral metastases. Materials and Methods: 11 Patients with 17 vertebral metastases and adjacent anterior epidural infiltration were reviewed retrospectively. All cases were studied by MRI. The routinely used imaging technique included spin echo (SE) T 1 and T 2 weighted sequences in the sagittal plane native and T 1 -SE without and with Gd-DTPA in the axial planes. The radiological findings of these phenomena and the anatomy were studied. Results: We observed these phenomena to be uni- or bilateral in 88.3% of all cases with intraspinal anterior epidural carcinomatous infiltration, especially in that part of the vertebral body where the basal vertebral venous plexus was located. Conclusion: We conclude that vertebral metastases respect the midline. We interpret this fact as being due the anatomy of the vertebral body and especially its stabilization by the posterior longitudinal ligament. These findings may be helpful in the differential diagnosis of vertebral body metastases with epidural infiltration in contrast to intraspinal processes which proceed with the destruction of the vertebral body. (orig.) [de

Stent assisted coil embolization of a dissecting aneurysm of the vertebral artery: a case involving a patient with hypoplasia of the contralateral vertebral artery

International Nuclear Information System (INIS)

Kim, Hyun Jin; Jeong, Hae Woong; Cho, Jae Kwoeng; Park, Jeong Hoon; Koo, Yong Woon; Baik, Seung Kug

2002-01-01

A dissecting aneurysm of the vertebral artery may be treated conservatively, surgically, or using an endovascular approach. Proximal clipping, wrapping or trapping are surgical treatment methods, and endovascular treatment with coils and balloons is performed where a dissecting aneurysm is located near the midline or the appropriate surgical manipulation is difficult. As the contralateral vertebral artery of this patient was hypoplastic, the stent-assisted coil embolization technique was employed to preserve the ipsilateral vertebral artery. We describe a clinical case of dissecting aneurysm of the vertebral artery occurring in a patient in whom a hypoplastic contralateral vertebral artery was successfully treated

COXA-VERTEBRAL SYNDROME AND ITS SIGNIFICANCE IN HIP ARTHROPLASTY (REVIEW

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A. O. Denisov

2012-01-01

Full Text Available Lumbosacral spine and hip joints is a complex physiological functions of the co-operation of a large number of anatomical structures. Lesions of the links in the system can mutually afflict each other. Combined pathology of the hip and lumbosacral spine is called hip-spine syndrome, or coxa-vertebral syndrome. Symptoms of the joint and spine are very similar and only a careful examination and clinical examination may find the differences. As the disease progresses the hip increases the restriction of movement, there is a contracture of the limbs in a vicious position, which leads to an increase in tilt of the pelvis, increased lumbar lordosis and to functional shortening of limbs on the affected side. This gives rise to functional impairment, and then strain the joints of his spine and disease - osteochondrosis and scoliosis. After the successful operation of total hip replacement is often progressive clinical lesions of vertebral segment, which is manifested pain and is often offset by the results of arthroplasty as the restoration of movement in the hip joint, and the change in length limb after arthroplasty leads to rupture formed a functional stereotype change in the mobility of the lumbar spine, pelvis regression bias that causes the dynamic compression spinal nerve root. Depending on the duration of the existence, severity and nature of changes in the pelvic girdle is suitable correction of equipment replacement surgery, including, for example, in some cases, deliberate shortening or lengthening the preservation of the lower extremity, offset change, etc.

Symptomatic intracranial vertebral artery atherosclerotic stenosis (≥70%) with concurrent contralateral vertebral atherosclerotic diseases in 88 patients treated with the intracranial stenting

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Wang, Zi-Liang [Stroke Center, Henan Provincial People’s Hospital, Zhengzhou University (China); Gao, Bu-Lang [Department of Medical Research Shijiazhuang First Hospital, Hebei Medical University (China); Li, Tian-Xiao, E-mail: litianxiaod@163.com [Stroke Center, Henan Provincial People’s Hospital, Zhengzhou University (China); Cai, Dong-Yang; Zhu, Liang-Fu; Bai, Wei-Xing; Xue, Jiang-Yu; Li, Zhao-Shuo [Stroke Center, Henan Provincial People’s Hospital, Zhengzhou University (China)

2015-09-15

Highlights: • Symptomatic vertebral artery stenosis can be treated with intracranial stenting. • Stenting for intracranial vertebral artery stenosis is safe and effective. • Stenting for intracranial vertebral artery stenosis can prevent long-term stroke. - Abstract: Purpose: To investigate the safety, effect and instent restenosis rate of Wingspan stenting in treating patients with intracranial vertebral artery atherosclerotic stenosis (70–99%) concurrent with contralateral vertebral artery atherosclerotic diseases. Materials and methods: Eighty-eight patients with severe symptomatic intracranial vertebral artery atherosclerotic stenosis (≥70%) combined with contralateral vertebral artery atherosclerotic diseases were treated with the Wingpsan stent. All the baseline, cerebral angiography, success rate, perioperative complications, clinical and imaging follow-up data were prospectively analyzed. Results: The success rate of stenting was 100%, and the mean stenotic rate was reduced from prestenting (84.9 ± 6.8)% to poststenting (17.2 ± 5.9)%. The perioperative stroke rate was 1.1%. Among eighty patients (90.9%) with clinical follow-up 8-62 months (mean 29.3 ± 17.2) poststenting, five (6.3%) had posterior circulation TIA only, three (3.8%) had mild stroke in the posterior circulation but recovered completely, and another five patients greater than 70 years old died of non-ischemic stroke. Imaging follow-up in 46 patients (52.3%) 5–54 months (mean 9.9 ± 9.9) following stenting revealed instent restenosis in 12 patients (26.1%) including 7 (58.3%) symptomatic restenosis. Age and residual stenosis were the two factors to significantly (P < 0.05) affect instent restenosis. Conclusion: Wingspan stenting in the intracranial vertebral artery atherosclerotic stenosis combined with contralateral vertebral artery atherosclerotic diseases has a low perioperative stroke rate and a good preventive effect on long-term ischemic stroke, but the instent restenosis

Congenital abnormalities of the vertebral column in ferrets.

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Proks, Pavel; Stehlik, Ladislav; Paninarova, Michaela; Irova, Katarina; Hauptman, Karel; Jekl, Vladimir

2015-01-01

Vertebral column pathologies requiring surgical intervention have been described in pet ferrets, however little information is available on the normal vertebral formula and congenital variants in this species. The purpose of this retrospective study was to describe vertebral formulas and prevalence of congenital vertebral anomalies in a sample of pet ferrets. Radiographs of 172 pet ferrets (96 males and 76 females) were included in this retrospective study. In 143 ferrets (83.14%), five different formulas of the vertebral column were recorded with normal morphology of vertebrae (rib attachment included) but with a variable number of thoracic (Th), lumbar (L), and sacral (S) vertebrae. The number of cervical (C) vertebrae was constant in all examined animals. Observed vertebral formulas were C7/Th14/L6/S3 (51.74%), C7/Th14/L6/S4 (22.10%), C7/Th14/L7/S3 (6.98%), C7/Th15/L6/S3 (1.74%), and C7/Th15/L6/S4 (0.58%). Formula C7/Th14/L6/S4 was significantly more common in males than in females (P < 0.05). Congenital spinal abnormalities were found in 29 ferrets (16.86%), mostly localized in the thoracolumbar and lumbosacral regions. The cervical region was affected in only one case. Transitional vertebrae represented the most common congenital abnormalities (26 ferrets) in the thoracolumbar (13 ferrets) and lumbosacral regions (10 ferrets) or simultaneously in both regions (three ferrets). Other vertebral anomalies included block (two ferrets) and wedge vertebra (one ferret). Spina bifida was not detected. Findings from the current study indicated that vertebral formulas may vary in ferrets and congenital abnormalities are common. This should be taken into consideration for surgical planning. © 2014 American College of Veterinary Radiology.

Three-dimensional geometric model of the middle segment of the thoracic spine based on graphical images for finite element analysis

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Rozilene Maria Cota Aroeira

2017-05-01

Full Text Available Abstract Introduction: Biomedical studies involve complex anatomical structures, which require specific methodology to generate their geometric models. The middle segment of the thoracic spine (T5-T10 is the site of the highest incidence of vertebral deformity in adolescents. Traditionally, its geometries are derived from computed tomography or magnetic resonance imaging data. However, this approach may restrict certain studies. The study aimed to generate two 3D geometric model of the T5-T10 thoracic spine segment, obtained from graphical images, and to create mesh for finite element studies. Methods A 3D geometric model of T5-T10 was generated using two anatomical images of T6 vertebra (side and top. The geometric model was created in Autodesk® Maya® 3D 2013, and the mesh process in HiperMesh and MeshMixer (v11.0.544 Autodesk. Results The T5-T10 thoracic segment model is presented with its passive components, bones, intervertebral discs and flavum, intertransverse and supraspinous ligaments, in different views, as well as the volumetric mesh. Conclusion The 3D geometric model generated from graphical images is suitable for application in non-patient-specific finite element model studies or, with restrictions, in the use of computed tomography or magnetic resonance imaging. This model may be useful for biomechanical studies related to the middle thoracic spine, the most vulnerable site for vertebral deformations.

Kyphoplasty for vertebral augmentation in the elderly with osteoporotic vertebral compression fractures: scenarios and review of recent studies.

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Bednar, Timothy; Heyde, Christoph E; Bednar, Grace; Nguyen, David; Volpi, Elena; Przkora, Rene

2013-11-01

Vertebral compression fractures caused by osteoporosis are among the most common fractures in the elderly. The treatment focuses on pain control, maintenance of independence, and management of the osteoporosis. Elderly patients often encounter adverse effects to pain medications, do not tolerate bed rest, and are not ideal candidates for invasive spinal reconstructive surgery. Percutaneous vertebral augmentation (vertebroplasty or kyphoplasty) has become popular as a less-invasive alternative. However, studies have questioned the effectiveness of these procedures. The authors conducted a MEDLINE search using relevant search terms including osteoporosis, osteoporotic vertebral compression fracture, elderly, kyphoplasty and vertebroplasty. Two elderly patients presented with a fracture of their third and first lumbar vertebral body, respectively. One patient progressed well with conservative treatment, whereas the other patient was hospitalized secondary to pain after conservative measures failed to offer improvement. The hospitalized patient subsequently opted for a kyphoplasty and was able to resume his normal daily activities after the procedure. Selecting patients on an individual case-by-case basis can optimize the effectiveness and outcomes of a vertebral augmentation. This process includes the documentation of an osteoporotic vertebral compression fracture with the aide of imaging studies, including the acuity of the fracture as well as the correlation with the physical examination findings. Patients who are functional and improving under a conservative regimen are not candidates for kyphoplasty. However, if the conservative management is not successful after 4 to 6 weeks and the patient is at risk to become bedridden, an augmentation should be considered. A kyphoplasty procedure may be preferred over vertebroplasty, given the lower risk profile and better outcomes regarding spinal alignment. Published by Elsevier HS Journals, Inc.

Non-contiguous multifocal vertebral osteomyelitis caused by Serratia marcescens.

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Lau, Jen Xin; Li, Jordan Yuanzhi; Yong, Tuck Yean

2015-03-01

Serratia marcescens is a common nosocomial infection but a rare cause of osteomyelitis and more so of vertebral osteomyelitis. Vertebral osteomyelitis caused by this organism has been reported in few studies. We report a case of S. marcescens vertebral discitis and osteomyelitis affecting multiple non-contiguous vertebras. Although Staphylococcus aureus is the most common cause of vertebral osteomyelitis, rare causes, such as S. marcescens, need to be considered, especially when risk factors such as intravenous heroin use, post-spinal surgery and immunosuppression are present. Therefore, blood culture and where necessary biopsy of the infected region should be undertaken to establish the causative organism and determine appropriate antibiotic susceptibility. Prompt diagnosis of S. marcescens vertebral osteomyelitis followed by the appropriate treatment can achieve successful outcomes.

Handed behavior in hagfish--an ancient vertebrate lineage--and a survey of lateralized behaviors in other invertebrate chordates and elongate vertebrates.

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Miyashita, Tetsuto; Palmer, A Richard

2014-04-01

Hagfish represent an ancient lineage of boneless and jawless vertebrates. Among several curious behaviors they exhibit, solitary individuals in one dominant genus of hagfish (Eptatretus spp.) regularly rest in a tightly coiled posture. We present the first systematic treatment of this distinctive behavior. Individual northeastern Pacific hagfish (E. stoutii) exhibited significant handedness (preferred orientation of coiling). However, right-coiling and left-coiling individuals were equally common in the population. Individual hagfish likely develop a preference for one direction by repeating the preceding coiling direction. We also revisit classical accounts of chordate natural history and compare the coiling behavior of Eptatretus with other handed or lateralized behaviors in non-vertebrate chordates, lampreys, and derived vertebrates with elongate bodies. Handed behaviors occur in many of these groups, but they likely evolved independently. In contrast to vertebrates, morphological asymmetries may bias lateralized larval behaviors toward one side in cephalochordates and tunicates. As a consequence, no known handed behavior can be inferred to have existed in the common ancestor of vertebrates.

Caudal lumbar vertebral fractures in California Quarter Horse and Thoroughbred racehorses.

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Collar, E M; Zavodovskaya, R; Spriet, M; Hitchens, P L; Wisner, T; Uzal, F A; Stover, S M

2015-09-01

To gain insight into the pathophysiology of equine lumbar vertebral fractures in racehorses. To characterise equine lumbar vertebral fractures in California racehorses. Retrospective case series and prospective case-control study. Racehorse post mortem reports and jockey injury reports were retrospectively reviewed. Vertebral specimens from 6 racehorses affected with lumbar vertebral fractures and 4 control racehorses subjected to euthanasia for nonspinal fracture were assessed using visual, radiographic, computed tomography and histological examinations. Lumbar vertebral fractures occurred in 38 Quarter Horse and 29 Thoroughbred racehorses over a 22 year period, primarily involving the 5th and/or 6th lumbar vertebrae (L5-L6; 87% of Quarter Horses and 48% of Thoroughbreds). Lumbar vertebral fractures were the third most common musculoskeletal cause of death in Quarter Horses and frequently involved a jockey injury. Lumbar vertebral specimens contained anatomical variations in the number of vertebrae, dorsal spinous processes and intertransverse articulations. Lumbar vertebral fractures examined in 6 racehorse specimens (5 Quarter Horses and one Thoroughbred) coursed obliquely in a cranioventral to caudodorsal direction across the adjacent L5-L6 vertebral endplates and intervertebral disc, although one case involved only one endplate. All cases had evidence of abnormalities on the ventral aspect of the vertebral bodies consistent with pre-existing, maladaptive pathology. Lumbar vertebral fractures occur in racehorses with pre-existing pathology at the L5-L6 vertebral junction that is likely predisposes horses to catastrophic fracture. Knowledge of these findings should encourage assessment of the lumbar vertebrae, therefore increasing detection of mild vertebral injuries and preventing catastrophic racehorse and associated jockey injuries. © 2014 EVJ Ltd.

Reintroduction of locally extinct vertebrates impacts arid soil fungal communities.

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Clarke, Laurence J; Weyrich, Laura S; Cooper, Alan

2015-06-01

Introduced species have contributed to extinction of native vertebrates in many parts of the world. Changes to vertebrate assemblages are also likely to alter microbial communities through coextinction of some taxa and the introduction of others. Many attempts to restore degraded habitats involve removal of exotic vertebrates (livestock and feral animals) and reintroduction of locally extinct species, but the impact of such reintroductions on microbial communities is largely unknown. We used high-throughput DNA sequencing of the fungal internal transcribed spacer I (ITS1) region to examine whether replacing exotic vertebrates with reintroduced native vertebrates led to changes in soil fungal communities at a reserve in arid central Australia. Soil fungal diversity was significantly different between dune and swale (interdune) habitats. Fungal communities also differed significantly between sites with exotic or reintroduced native vertebrates after controlling for the effect of habitat. Several fungal operational taxonomic units (OTUs) found exclusively inside the reserve were present in scats from reintroduced native vertebrates, providing a direct link between the vertebrate assemblage and soil microbial communities. Our results show that changes to vertebrate assemblages through local extinctions and the invasion of exotic species can alter soil fungal communities. If local extinction of one or several species results in the coextinction of microbial taxa, the full complement of ecological interactions may never be restored. © 2015 John Wiley & Sons Ltd.

Balloon kyphoplasty for aged osteoporotic vertebral compressive fractures using domestic instruments

International Nuclear Information System (INIS)

Sun Gang; Jin Peng; Yi Yuhai; Xie Zhiyong; Zhang Xuping; Zhang Kangli

2006-01-01

Objective: To evaluate the efficacy and safety of balloon kyphoplasty in the treatment of painful osteoporosis vertebral compressive fractures using instruments made in China. Methods: 10 cases of painful osteoporotic vertebral compressive fractures, involved 11 vertebrae. Under X-ray fluoroscopy monitoring, the inflatable balloon were inserted into the fractured vertebral body via transpedicular route bilaterally. The balloon was inflated with injected contrast agent to restore vertebral height and form a cavity within vertebral body. The cavity was then filled with bone cement in toothpaste state period. The postoperative symptoms and the radiographic findings of vertebral height recovery were observed. Results: Balloon kyphoplasty was successful in all 10 cases with dramatic pain relief within 48 hours after the procedure without clinical complications. The height restoration of vertebral body was satisfactory with correction of kyphosis up to 6 degree-24 degree. Leakage of a small quantity of bone cement occurred at only the anterior border of the vertebral body. Conclusions: Kyphoplasty using domestic instruments for painful osteoporotic vertebral compressive fractures was effective and safe. (authors)

Vertebrate richness and biogeography in the Big Thicket of Texas

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Michael H MacRoberts; Barbara R. MacRoberts; D. Craig Rudolph

2010-01-01

The Big Thicket of Texas has been described as rich in species and a “crossroads:” a place where organisms from many different regions meet. We examine the species richness and regional affiliations of Big Thicket vertebrates. We found that the Big Thicket is neither exceptionally rich in vertebrates nor is it a crossroads for vertebrates. Its vertebrate fauna is...

Imperfect isolation: factors and filters shaping Madagascar's extant vertebrate fauna.

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Samonds, Karen E; Godfrey, Laurie R; Ali, Jason R; Goodman, Steven M; Vences, Miguel; Sutherland, Michael R; Irwin, Mitchell T; Krause, David W

2013-01-01

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar's colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island's biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island's paleogeographical evolution to determine how particular events influenced the arrival of the island's extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar's tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island's isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar's extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar's unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more

A unified anatomy ontology of the vertebrate skeletal system.

Directory of Open Access Journals (Sweden)

Wasila M Dahdul

Full Text Available The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO, to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish and multispecies (teleost, amphibian vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages, and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO, Gene Ontology (GO, Uberon, and Cell Ontology (CL, and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.

A unified anatomy ontology of the vertebrate skeletal system.

Science.gov (United States)

Dahdul, Wasila M; Balhoff, James P; Blackburn, David C; Diehl, Alexander D; Haendel, Melissa A; Hall, Brian K; Lapp, Hilmar; Lundberg, John G; Mungall, Christopher J; Ringwald, Martin; Segerdell, Erik; Van Slyke, Ceri E; Vickaryous, Matthew K; Westerfield, Monte; Mabee, Paula M

2012-01-01

The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity.

A Unified Anatomy Ontology of the Vertebrate Skeletal System

Science.gov (United States)

Dahdul, Wasila M.; Balhoff, James P.; Blackburn, David C.; Diehl, Alexander D.; Haendel, Melissa A.; Hall, Brian K.; Lapp, Hilmar; Lundberg, John G.; Mungall, Christopher J.; Ringwald, Martin; Segerdell, Erik; Van Slyke, Ceri E.; Vickaryous, Matthew K.; Westerfield, Monte; Mabee, Paula M.

2012-01-01

The skeleton is of fundamental importance in research in comparative vertebrate morphology, paleontology, biomechanics, developmental biology, and systematics. Motivated by research questions that require computational access to and comparative reasoning across the diverse skeletal phenotypes of vertebrates, we developed a module of anatomical concepts for the skeletal system, the Vertebrate Skeletal Anatomy Ontology (VSAO), to accommodate and unify the existing skeletal terminologies for the species-specific (mouse, the frog Xenopus, zebrafish) and multispecies (teleost, amphibian) vertebrate anatomy ontologies. Previous differences between these terminologies prevented even simple queries across databases pertaining to vertebrate morphology. This module of upper-level and specific skeletal terms currently includes 223 defined terms and 179 synonyms that integrate skeletal cells, tissues, biological processes, organs (skeletal elements such as bones and cartilages), and subdivisions of the skeletal system. The VSAO is designed to integrate with other ontologies, including the Common Anatomy Reference Ontology (CARO), Gene Ontology (GO), Uberon, and Cell Ontology (CL), and it is freely available to the community to be updated with additional terms required for research. Its structure accommodates anatomical variation among vertebrate species in development, structure, and composition. Annotation of diverse vertebrate phenotypes with this ontology will enable novel inquiries across the full spectrum of phenotypic diversity. PMID:23251424

50 CFR 17.84 - Special rules-vertebrates.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 2 2010-10-01 2010-10-01 false Special rules-vertebrates. 17.84 Section 17.84 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR....84 Special rules—vertebrates. (a) Delmarva Peninsula fox squirrel (Sciurus niger cinereus). (1) The...

Vertebral column regionalisation in Chinook salmon, Oncorhynchus tshawytscha.

Science.gov (United States)

De Clercq, A; Perrott, M R; Davie, P S; Preece, M A; Wybourne, B; Ruff, N; Huysseune, A; Witten, P E

2017-10-01

Teleost vertebral centra are often similar in size and shape, but vertebral-associated elements, i.e. neural arches, haemal arches and ribs, show regional differences. Here we examine how the presence, absence and specific anatomical and histological characters of vertebral centra-associated elements can be used to define vertebral column regions in juvenile Chinook salmon (Oncorhynchus tshawytscha). To investigate if the presence of regions within the vertebral column is independent of temperature, animals raised at 8 and 12 °C were studied at 1400 and 1530 degreedays, in the freshwater phase of the life cycle. Anatomy and composition of the skeletal tissues of the vertebral column were analysed using Alizarin red S whole-mount staining and histological sections. Six regions, termed I-VI, are recognised in the vertebral column of specimens of both temperature groups. Postcranial vertebrae (region I) carry neural arches and parapophyses but lack ribs. Abdominal vertebrae (region II) carry neural arches and ribs that articulate with parapophyses. Elastic- and fibrohyaline cartilage and Sharpey's fibres connect the bone of the parapophyses to the bone of the ribs. In the transitional region (III) vertebrae carry neural arches and parapophyses change stepwise into haemal arches. Ribs decrease in size, anterior to posterior. Vestigial ribs remain attached to the haemal arches with Sharpey's fibres. Caudal vertebrae (region IV) carry neural and haemal arches and spines. Basidorsals and basiventrals are small and surrounded by cancellous bone. Preural vertebrae (region V) carry neural and haemal arches with modified neural and haemal spines to support the caudal fin. Ural vertebrae (region VI) carry hypurals and epurals that represent modified haemal and neural arches and spines, respectively. The postcranial and transitional vertebrae and their respective characters are usually recognised, but should be considered as regions within the vertebral column of teleosts

Automated Detection, Localization, and Classification of Traumatic Vertebral Body Fractures in the Thoracic and Lumbar Spine at CT.

Science.gov (United States)

Burns, Joseph E; Yao, Jianhua; Muñoz, Hector; Summers, Ronald M

2016-01-01

To design and validate a fully automated computer system for the detection and anatomic localization of traumatic thoracic and lumbar vertebral body fractures at computed tomography (CT). This retrospective study was HIPAA compliant. Institutional review board approval was obtained, and informed consent was waived. CT examinations in 104 patients (mean age, 34.4 years; range, 14-88 years; 32 women, 72 men), consisting of 94 examinations with positive findings for fractures (59 with vertebral body fractures) and 10 control examinations (without vertebral fractures), were performed. There were 141 thoracic and lumbar vertebral body fractures in the case set. The locations of fractures were marked and classified by a radiologist according to Denis column involvement. The CT data set was divided into training and testing subsets (37 and 67 subsets, respectively) for analysis by means of prototype software for fully automated spinal segmentation and fracture detection. Free-response receiver operating characteristic analysis was performed. Training set sensitivity for detection and localization of fractures within each vertebra was 0.82 (28 of 34 findings; 95% confidence interval [CI]: 0.68, 0.90), with a false-positive rate of 2.5 findings per patient. The sensitivity for fracture localization to the correct vertebra was 0.88 (23 of 26 findings; 95% CI: 0.72, 0.96), with a false-positive rate of 1.3. Testing set sensitivity for the detection and localization of fractures within each vertebra was 0.81 (87 of 107 findings; 95% CI: 0.75, 0.87), with a false-positive rate of 2.7. The sensitivity for fracture localization to the correct vertebra was 0.92 (55 of 60 findings; 95% CI: 0.79, 0.94), with a false-positive rate of 1.6. The most common cause of false-positive findings was nutrient foramina (106 of 272 findings [39%]). The fully automated computer system detects and anatomically localizes vertebral body fractures in the thoracic and lumbar spine on CT images with a

Transoral vertebral augmentation with polymethylmethacrylate in the treatment of a patient with a dens fracture nonunion and subarticular vertebral body fracture of C2

International Nuclear Information System (INIS)

Beall, Douglas P.; Martin, Hal D.; Stapp, Annette M.; Stanfield, Matthew

2007-01-01

The injection of polymethylmethacrylate (PMMA) is a minimally invasive, image-guided procedure used to treat vertebral fractures due to osteoporosis, metastatic lesions, multiple myeloma, and benign but destabilizing bone tumors. The injection of PMMA into the C2 vertebral body using the transoral technique has been reported in three separate patients for treatment of benign tumors (a vertebral hemangioma and an aneurysmal bone cyst) and for multiple myeloma in the third patient. Although the injection of PMMA into the vertebral body is most commonly performed to treat benign vertebral compression fractures, a transoral C2 approach has not been reported in the English literature as a treatment for a benign fracture of C2. We report the treatment of a fracture and nonunion of the base of the dens and a subarticular fracture of the vertebral body of C2 using a bilateral transoral approach. (orig.)

Vertebral Fractures After Discontinuation of Denosumab

DEFF Research Database (Denmark)

Cummings, Steven R; Ferrari, Serge; Eastell, Richard

2018-01-01

. We analyzed the risk of new or worsening vertebral fractures, especially multiple vertebral fractures, in participants who discontinued denosumab during the FREEDOM study or its Extension. Participants received ≥2 doses of denosumab or placebo Q6M, discontinued treatment, and stayed in the study ≥7...... months after the last dose. Of 1001 participants who discontinued denosumab during FREEDOM or Extension, the vertebral fracture rate increased from 1.2 per 100 participant-years during the on-treatment period to 7.1, similar to participants who received and then discontinued placebo (n = 470; 8.5 per 100....... Therefore, patients who discontinue denosumab should rapidly transition to an alternative antiresorptive treatment. Clinicaltrails.gov: NCT00089791 (FREEDOM) and NCT00523341 (Extension). © 2017 American Society for Bone and Mineral Research....

The characteristic of rBMD distribution in lumbar vertebral body

International Nuclear Information System (INIS)

Wang Chenguang; Xiao Xiangsheng; Chen Xingrong; Shen Tianzhen; Liu Guanghua; Hong Qingjian; Ji Rongming; Zhou Weiming

1998-01-01

Purpose: To determine the distribution and variation of rBMD in human lumbar vertebral body. Methods: The BMD and rBMD of 28 samples of lumbar body were measured with QCT. The rBMD was measured in the regions of anterior, anterolateral, posterolateral and central, superior-level, middle-level and inferior-level of the vertebral bodies. The relationship between BMD and rBMD were statistically analysed with multiple regression. Results: The rBMD of the inferior vertebral body was higher than that of the superior and middle portions (P<0.05); the central and posterolateral higher than the anterior and anterolateral (P<0.05). The rBMD of posterioinferior vertebral body was the highest. The multiple regression showed that the standard partial regression coefficient of inferior was larger than the superior and middle; the anterior and central were larger than the other regions of the vertebra. Variations of the BMD of vertebral body were mostly related to the rBMD of anterior and central parts. Conclusion: The distribution of BMD are heterogeneous in vertebral body. The anterior and central part of vertebral body are most sensitive to bone loss in osteoporosis. It is emphasized that the rBMD of anterior and central part of vertebral body should be measured for following the osteoporosis

Differential preservation of vertebrates in Southeast Asian caves

Directory of Open Access Journals (Sweden)

Julien Louys

2017-09-01

Full Text Available Caves have been an important source of vertebrate fossils for much of Southeast Asia, particularly for the Quaternary. Despite this importance, the mechanisms by which vertebrate remains accumulate and preserve in Southeast Asian caves has never been systematically reviewed or examined. Here, we present the results of three years of cave surveys in Indonesia and Timor-Leste, describing cave systems and their attendant vertebrate accumulations in diverse geological, biogeographical, and environmental settings. While each cave system is unique, we find that the accumulation and preservation of vertebrate remains are highly dependent on local geology and environment. These factors notwithstanding, we find the dominant factor responsible for faunal deposition is the presence or absence of biological accumulating agents, a factor directly dictated by biogeographical history. In small, isolated, volcanic islands, the only significant accumulation occurs in archaeological settings, thereby limiting our understanding of the palaeontology of those islands prior to human arrival. In karstic landscapes on both oceanic and continental islands, our understanding of the long-term preservation of vertebrates is still in its infancy. The formation processes of vertebrate-bearing breccias, their taphonomic histories, and the criteria used to determine whether these represent syngenetic or multiple deposits remain critically understudied. The latter in particular has important implications for arguments on how breccia deposits from the region should be analysed and interpreted when reconstructing palaeoenvironments.

Worldwide prevalence and incidence of osteoporotic vertebral fractures.

Science.gov (United States)

Ballane, G; Cauley, J A; Luckey, M M; El-Hajj Fuleihan, G

2017-05-01

We investigated the prevalence and incidence of vertebral fractures worldwide. We used a systematic Medline search current to 2015 and updated as per authors' libraries. A total of 62 articles of fair to good quality and comparable methods for vertebral fracture identification were considered. The prevalence of morphometric vertebral fractures in European women is highest in Scandinavia (26%) and lowest in Eastern Europe (18%). Prevalence rates in North America (NA) for White women ≥50 are 20-24%, with a White/Black ratio of 1.6. Rates in women ≥50 years in Latin America are overall lower than Europe and NA (11-19%). In Asia, rates in women above ≥65 are highest in Japan (24%), lowest in Indonesia (9%), and in the Middle East, Lebanon, rates are 20%. The highest-lowest ratio between countries, within and across continents, varied from 1.4-2.6. Incidence data is less abundant and more heterogeneous. Age-standardized rates in studies combining hospitalized and ambulatory vertebral fractures are highest in South Korea, USA, and Hong Kong and lowest in the UK. Neither a North-South gradient nor a relation to urbanization is evident. Conversely, the incidence of hospitalized vertebral fractures in European patients ≥50 shows a North-South gradient with 3-3.7-fold variability. In the USA, rates in Whites are approximately 4-fold higher than in Blacks. Vertebral fractures variation worldwide is lower than observed with hip fractures, and some of highest rates are unexpectedly from Asia. Better quality representative studies are needed. We investigate the occurrence of vertebral fractures, worldwide, using published data current until the present. Worldwide, the variation in vertebral fractures is lower than observed for hip fractures. Some of the highest rates are from North America and unexpectedly Asia. The highest-lowest ratio between countries, within and across continents, varied from 1.4-2.6. Better quality representative data is needed.

Computerized tomography of the vertebral column following traumatic lesion

International Nuclear Information System (INIS)

Taenzer, B.; Gmelin, E.; Burmester, E.; Babaian, E.; Weiss, H.D.; Hohlbach, G.

1984-01-01

In 58 patients with lesions of the vertebral column in the thoracal and lumbar section established by conventional X-ray, the informative power of computerized tomography was tested. Axial projection with the superimposition-free presentation of bone and soft-tissue structures in the motional segment clears up the diagnostically decisive question of the extent of the lesion and form of fracture, and thus provides information on the stability or instability of the fracture relevant for the therapeutic action taken. All patients had compression fractures of vertebrae, with a fragment of the front edge broken away in 50 cases and one of the back edge broken away in 17 cases. In 30 cases the intervertebral disks were damaged. 43 fractures were stable, 25 were unstable. The instability of 13 fractures was only recognized by CT. In essence, the diagnostic action to be taken begins with a grand-survey X-ray in two planes as a screening, with computerized tomography following in the positive case. Conventional tomograms are not necessary. (BWU) [de

Molecular evolution of proopiomelanocortin in early vertebrates; Gensakudobutsu hoya no shinkeisen ni saguru fukujinhishitsu sigeki horumon no kigen to bunshi shinka

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Akiyoshi [Kitasato University, Tokyo (Japan). School of Fishieries Sciences

1998-12-16

Proolpiomelanocortin (POMC) is a precursor for melanotrophin (MSH) and {beta}-endorphin that regulate stress and environmental adaptation. The present study was undertaken to provide insight into the molecular evolution of POMC in the early vertebrates by examining structures of POMCs in protochordates and in ancient and advanced fishes. Lungfish POMC is similar to tetrapods because they include three MSHs ({alpha}, {beta} and {gamma}) and {beta}-endorphin. In contrast to the consistent occurrence of three MSHs in tetrapods and dipnoans, fish POMC varies in the number of MSH types it contains. POMCs of tuna and sturgeon lack {gamma}-MSH whereas POMC of dogfish has a forth ({delta}) MSH in addition to {alpha}-, {beta}- and {gamma}-MSH. b-endorphin, however, occurs in all vertebrates. These results suggest that POMC has evolved by duplication, insertion and deletion of MSH genomic segments. The diversity of MSH may have contributed to development of the ability to adapt to different conditions. (author)

Clinical and radiological evaluation in vertebral artery dissections

Directory of Open Access Journals (Sweden)

Murat Çabalar

2013-04-01

Full Text Available In recent years, vertebral artery dissection (VAD is reported more frequently as a cause of young cerebrovascular accidents. It can occur spontaneously or following a neck manipulation and trauma. The patients were 3 females (mean age: 35±26 years and 7 males (mean age: 37.71±4.96 years. Only 2 patients described neck trauma. Cerebellar findings were prominent in all cases. On radiological investigation, vascular changes of vertebral arteries were detected bilaterally in 2 cases, right in 5 and left in 3 cases. All the cases were treated with anticoagulant therapy and cured but 1 with sequela. Prognosis of vertebral artery dissection is generally good by early diagnosis and treatment. In this article, we reported clinical and radiological properties of 10 vertebral artery dissection cases.

The origin of the vertebrate skeleton

Science.gov (United States)

Pivar, Stuart

2011-01-01

The anatomy of the human and other vertebrates has been well described since the days of Leonardo da Vinci and Vesalius. The causative origin of the configuration of the bones and of their shapes and forms has been addressed over the ensuing centuries by such outstanding investigators as Goethe, Von Baer, Gegenbauer, Wilhelm His and D'Arcy Thompson, who sought to apply mechanical principles to morphogenesis. However, no coherent causative model of morphogenesis has ever been presented. This paper presents a causative model for the origin of the vertebrate skeleton, based on the premise that the body is a mosaic enlargement of self-organized patterns engrained in the membrane of the egg cell. Drawings illustrate the proposed hypothetical origin of membrane patterning and the changes in the hydrostatic equilibrium of the cytoplasm that cause topographical deformations resulting in the vertebrate body form.

An invertebrate stomach's view on vertebrate ecology: certain invertebrates could be used as "vertebrate samplers" and deliver DNA-based information on many aspects of vertebrate ecology.

Science.gov (United States)

Calvignac-Spencer, Sébastien; Leendertz, Fabian H; Gilbert, M Thomas P; Schubert, Grit

2013-11-01

Recent studies suggest that vertebrate genetic material ingested by invertebrates (iDNA) can be used to investigate vertebrate ecology. Given the ubiquity of invertebrates that feed on vertebrates across the globe, iDNA might qualify as a very powerful tool for 21st century population and conservation biologists. Here, we identify some invertebrate characteristics that will likely influence iDNA retrieval and elaborate on the potential uses of invertebrate-derived information. We hypothesize that beyond inventorying local faunal diversity, iDNA should allow for more profound insights into wildlife population density, size, mortality, and infectious agents. Based on the similarities of iDNA with other low-quality sources of DNA, a general technical framework for iDNA analyses is proposed. As it is likely that no such thing as a single ideal iDNA sampler exists, forthcoming research efforts should aim at cataloguing invertebrate properties relevant to iDNA retrieval so as to guide future usage of the invertebrate tool box. © 2013 WILEY Periodicals, Inc.

Use of cervical vertebral dimensions for assessment of children growth.

Science.gov (United States)

Caldas, Maria de Paula; Ambrosano, Gláucia Maria Bovi; Haiter-Neto, Francisco

2007-04-01

The purpose of this study was to investigate whether skeletal maturation using cephalometric radiographs could be used in a Brazilian population. The study population was selected from the files of the Oral Radiological Clinic of the Dental School of Piracicaba, Brazil and consisted of 128 girls and 110 boys (7.0 to 15.9 years old) who had cephalometric and hand-wrist radiographs taken on the same day. Cervical vertebral bone age was evaluated using the method described by Mito and colleagues in 2002. Bone age was assessed by the Tanner-Whitehouse (TW3) method and was used as a gold standard to determine the reliability of cervical vertebral bone age. An analysis of variance and Tukey's post-hoc test were used to compare cervical vertebral bone age, bone age and chronological age at 5% significance level. The analysis of the Brazilian female children data showed that there was a statistically significant difference (pcervical vertebral bone age and chronological age and between bone age and chronological age. However no statistically significant difference (p>0.05) was found between cervical vertebral bone age and bone age. Differently, the analysis of the male children data revealed a statistically significant difference (pcervical vertebral bone age and bone age and between cervical vertebral bone age and chronological age (pmaturation on cephalometric radiographs by determination of vertebral bone age can be applied to Brazilian females only. The development of a new method to objectively evaluate cervical vertebral bone age in males is needed.

The origin of vertebrate limbs.

Science.gov (United States)

Coates, M I

1994-01-01

The earliest tetrapod limbs are polydactylous, morphologically varied and do not conform to an archetypal pattern. These discoveries, combined with the unravelling of limb developmental morphogenetic and regulatory mechanisms, have prompted a re-examination of vertebrate limb evolution. The rich fossil record of vertebrate fins/limbs, although restricted to skeletal tissues, exceeds the morphological diversity of the extant biota, and a systematic approach to limb evolution produces an informative picture of evolutionary change. A composite framework of several phylogenetic hypotheses is presented incorporating living and fossil taxa, including the first report of an acanthodian metapterygium and a new reconstruction of the axial skeleton and caudal fin of Acanthostega gunnari. Although significant nodes in vertebrate phylogeny remain poorly resolved, clear patterns of morphogenetic evolution emerge: median fin origination and elaboration initially precedes that of paired fins; pectoral fins initially precede pelvic fin development; evolving patterns of fin distribution, skeletal tissue diversity and structural complexity become decoupled with increased taxonomic divergence. Transformational sequences apparent from the fish-tetrapod transition are reiterated among extant lungfishes, indicating further directions for comparative experimental research. The evolutionary diversification of vertebrate fin and limb patterns challenges a simple linkage between Hox gene conservation, expression and morphology. A phylogenetic framework is necessary in order to distinguish shared from derived characters in experimental model regulatory systems. Hox and related genomic evolution may include convergent patterns underlying functional and morphological diversification. Brachydanio is suggested as an example where tail-drive patterning demands may have converged with the regulation of highly differentiated limbs in tetrapods.

Preoperative MRI evaluation of vertebral hemangiomas treated with percutaneous vertebroplasty

International Nuclear Information System (INIS)

Liu Xiaoping; Wu Chungen; Li Minghua; Li Yuehua; Gu Yifeng; Cheng Yongde

2012-01-01

Objective: To discuss the clinical value of preoperative magnetic resonance imaging examination in guiding the treatment of vertebral hemangiomas with percutaneous vertebroplasty (PVP). Methods: A total of 286 patients with vertebral hemangiomas detected on spine MRI in authors' Department were enrolled in this study. The patient's age, the lesion's size and location, the clinical symptoms, MRI findings, etc. were retrospectively analyzed. Results: A total of 336 vertebral bodies were affected in 286 patients. The lesions were mainly located at the lumbar spine (43.15%) and the thoracic spine (37.80%). The highest incidence of disease was seen in 50-59 years old patients (34.62%). The mean diameter of the lesions was 14.56 mm. Solitary lesion was seen in 85.66% of patients, while two vertebral bodies involved were seen in 10.14% of patients. Twelve cases (4.20%) simply presented as back pain at the related vertebral bodies. Two patients showed signs due to spinal cord compression. All aggressive vertebral hemangiomas were manifested as iso-lower signal on T1-weighted images and higher signal on T2-weighted images. Simple PVP was performed in 4 cases, and subtotal tumor excision together with PVP was carried out in two patients with aggressive vertebral hemangiomas. Conclusion: Evaluation of vertebral hemangiomas with MRI performed prior to percutaneous vertebroplasty is very helpful in guiding the selection of therapeutic scheme. (authors)

Multiple chromosomal rearrangements structured the ancestral vertebrate Hox-bearing protochromosomes.

Directory of Open Access Journals (Sweden)

Vincent J Lynch

2009-01-01

Full Text Available While the proposal that large-scale genome expansions occurred early in vertebrate evolution is widely accepted, the exact mechanisms of the expansion--such as a single or multiple rounds of whole genome duplication, bloc chromosome duplications, large-scale individual gene duplications, or some combination of these--is unclear. Gene families with a single invertebrate member but four vertebrate members, such as the Hox clusters, provided early support for Ohno's hypothesis that two rounds of genome duplication (the 2R-model occurred in the stem lineage of extant vertebrates. However, despite extensive study, the duplication history of the Hox clusters has remained unclear, calling into question its usefulness in resolving the role of large-scale gene or genome duplications in early vertebrates. Here, we present a phylogenetic analysis of the vertebrate Hox clusters and several linked genes (the Hox "paralogon" and show that different phylogenies are obtained for Dlx and Col genes than for Hox and ErbB genes. We show that these results are robust to errors in phylogenetic inference and suggest that these competing phylogenies can be resolved if two chromosomal crossover events occurred in the ancestral vertebrate. These results resolve conflicting data on the order of Hox gene duplications and the role of genome duplication in vertebrate evolution and suggest that a period of genome reorganization occurred after genome duplications in early vertebrates.

Dissection of the V4 segment of the vertebral artery: clinicoradiologic manifestations and endovascular treatment

Energy Technology Data Exchange (ETDEWEB)

Yoon, Woong; Seo, Jeong Jin [Chonnam National University Medical School, Department of Radiology, Chonnam National University Hospital, 501-757Dong-gu, Gwangju (Korea); Kim, Tae Sun [Chonnam National University Medical School, Department of Neurosurgery, Chonnam National University Hospital, Dong-gu, Gwangju (Korea); Do, Huy M.; Jayaraman, Mahesh V.; Marks, Michael P. [Stanford University Medical Center, Department of Radiology, Stanford, California (United States)

2007-04-15

Intracranial vertebral artery (VA) dissection has three clinical presentations: ischemia, hemorrhage, and mass effect. Imaging findings of intracranial VA dissections vary according to clinical presentation. Irregular stenosis or occlusion of the VA is the most common finding in patients with posterior fossa infarction, whereas a dissecting aneurysm is the main feature in those with acute subarachnoid hemorrhage. A chronic, giant, dissecting aneurysm can cause mass effect on the brain stem or cranial nerves, as well as distal embolism. Magnetic resonance imaging is useful for detection of intramural hematomas and intimal flaps, both of which are diagnostic of VA dissection. Multidetector computed tomography angiography is increasingly used for diagnosis of VA dissection. Catheter angiography is still beneficial for evaluation of precise endoluminal morphology of the dissection before surgical or endovascular intervention. Endovascular treatment is now considered a major therapeutic option for patients with a ruptured dissecting aneurysm or a chronic dissecting aneurysm. Anticoagulation therapy is currently considered the initial treatment of choice in patients with posterior circulation ischemic symptoms. Endovascular treatment, such as stent-assisted angioplasty or coil occlusion at the dissection site, can be performed in selected patients with posterior fossa ischemic symptoms. (orig.)

Dissection of the V4 segment of the vertebral artery: clinicoradiologic manifestations and endovascular treatment

International Nuclear Information System (INIS)

Yoon, Woong; Seo, Jeong Jin; Kim, Tae Sun; Do, Huy M.; Jayaraman, Mahesh V.; Marks, Michael P.

2007-01-01

Intracranial vertebral artery (VA) dissection has three clinical presentations: ischemia, hemorrhage, and mass effect. Imaging findings of intracranial VA dissections vary according to clinical presentation. Irregular stenosis or occlusion of the VA is the most common finding in patients with posterior fossa infarction, whereas a dissecting aneurysm is the main feature in those with acute subarachnoid hemorrhage. A chronic, giant, dissecting aneurysm can cause mass effect on the brain stem or cranial nerves, as well as distal embolism. Magnetic resonance imaging is useful for detection of intramural hematomas and intimal flaps, both of which are diagnostic of VA dissection. Multidetector computed tomography angiography is increasingly used for diagnosis of VA dissection. Catheter angiography is still beneficial for evaluation of precise endoluminal morphology of the dissection before surgical or endovascular intervention. Endovascular treatment is now considered a major therapeutic option for patients with a ruptured dissecting aneurysm or a chronic dissecting aneurysm. Anticoagulation therapy is currently considered the initial treatment of choice in patients with posterior circulation ischemic symptoms. Endovascular treatment, such as stent-assisted angioplasty or coil occlusion at the dissection site, can be performed in selected patients with posterior fossa ischemic symptoms. (orig.)

Vascular complications of prosthetic inter-vertebral discs.

Science.gov (United States)

Daly, Kevin J; Ross, E Raymond S; Norris, Heather; McCollum, Charles N

2006-10-01

Five consecutive cases of prosthetic inter-vertebral disc displacement with severe vascular complications on revisional surgery are described. The objective of this case report is to warn spinal surgeons that major vascular complications are likely with anterior displacement of inter-vertebral discs. We have not been able to find a previous report on vascular complications associated with anterior displacement of prosthetic inter-vertebral discs. In all five patients the prosthetic disc had eroded into the bifurcation of the inferior vena cava and the left common iliac vein. In three cases the aortic bifurcation was also involved. The fibrosis was so severe that dissecting out the arteries and veins to provide access to the relevant disc proved impossible. Formal division of the left common iliac vein and artery with subsequent repair was our solution. Anterior inter-vertebral disc displacement was associated with severe vascular injury. Preventing anterior disc displacement is essential in disc design. In the event of anterior displacement, disc removal should be planned with a Vascular Surgeon.

Evolution of the vertebrate phototransduction cascade activation steps.

Science.gov (United States)

Lamb, Trevor D; Hunt, David M

2017-11-01

We examine the molecular phylogeny of the proteins underlying the activation steps of vertebrate phototransduction, for both agnathan and jawed vertebrate taxa. We expand the number of taxa analysed and we update the alignment and tree building methodology from a previous analysis. For each of the four primary components (the G-protein transducin alpha subunit, Gα T , the cyclic GMP phosphodiesterase, PDE6, and the alpha and beta subunits of the cGMP-gated ion channel, CNGC), the phylogenies appear consistent with expansion from an ancestral proto-vertebrate cascade during two rounds of whole-genome duplication followed by divergence of the agnathan and jawed vertebrate lineages. In each case, we consider possible scenarios for the underlying gene duplications and losses, and we apply relevant constraints to the tree construction. From tests of the topology of the resulting trees, we obtain a scenario for the expansion of each component during 2R that accurately fits the observations. Similar analysis of the visual opsins indicates that the only expansion to have occurred during 2R was the formation of Rh1 and Rh2. Finally, we propose a hypothetical scenario for the conversion of an ancestral chordate cascade into the proto-vertebrate phototransduction cascade, prior to whole-genome duplication. Together, our models provide a plausible account for the origin and expansion of the vertebrate phototransduction cascade. Copyright © 2017 Elsevier Inc. All rights reserved.

iDNA screening: Disease vectors as vertebrate samplers.

Science.gov (United States)

Kocher, Arthur; de Thoisy, Benoit; Catzeflis, François; Valière, Sophie; Bañuls, Anne-Laure; Murienne, Jérôme

2017-11-01

In the current context of global change and human-induced biodiversity decline, there is an urgent need for developing sampling approaches able to accurately describe the state of biodiversity. Traditional surveys of vertebrate fauna involve time-consuming and skill-demanding field methods. Recently, the use of DNA derived from invertebrate parasites (leeches and blowflies) was suggested as a new tool for vertebrate diversity assessment. Bloodmeal analyses of arthropod disease vectors have long been performed to describe their feeding behaviour, for epidemiological purposes. On the other hand, this existing expertise has not yet been applied to investigate vertebrate fauna per se. Here, we evaluate the usefulness of hematophagous dipterans as vertebrate samplers. Blood-fed sand flies and mosquitoes were collected in Amazonian forest sites and analysed using high-throughput sequencing of short mitochondrial markers. Bloodmeal identifications highlighted contrasting ecological features and feeding behaviour among dipteran species, which allowed unveiling arboreal and terrestrial mammals of various body size, as well as birds, lizards and amphibians. Additionally, lower vertebrate diversity was found in sites undergoing higher levels of human-induced perturbation. These results suggest that, in addition to providing precious information on disease vector host use, dipteran bloodmeal analyses may represent a useful tool in the study of vertebrate communities. Although further effort is required to validate the approach and consider its application to large-scale studies, this first work opens up promising perspectives for biodiversity monitoring and eco-epidemiology. © 2017 John Wiley & Sons Ltd.

Evolution of vertebrate sex chromosomes and dosage compensation.

Science.gov (United States)

Graves, Jennifer A Marshall

2016-01-01

Differentiated sex chromosomes in mammals and other vertebrates evolved independently but in strikingly similar ways. Vertebrates with differentiated sex chromosomes share the problems of the unequal expression of the genes borne on sex chromosomes, both between the sexes and with respect to autosomes. Dosage compensation of genes on sex chromosomes is surprisingly variable - and can even be absent - in different vertebrate groups. Systems that compensate for different gene dosages include a wide range of global, regional and gene-by-gene processes that differ in their extent and their molecular mechanisms. However, many elements of these control systems are similar across distant phylogenetic divisions and show parallels to other gene silencing systems. These dosage systems cannot be identical by descent but were probably constructed from elements of ancient silencing mechanisms that are ubiquitous among vertebrates and shared throughout eukaryotes.

Diffusion-Weighted MRI Assessment of Adjacent Disc Degeneration After Thoracolumbar Vertebral Fractures

Energy Technology Data Exchange (ETDEWEB)

Noriega, David C., E-mail: dcnoriega1970@gmail.com [Valladolid University Hospital, Spine Department (Spain); Marcia, Stefano, E-mail: stemarcia@gmail.com [SS. Trinità Hospital ASL 8 Cagliari, Department of Radiology (Italy); Ardura, Francisco, E-mail: fardura@ono.com [Valladolid University Hospital, Spine Department (Spain); Lite, Israel Sanchez, E-mail: israelslite@hotmail.com [Valladolid University Hospital, Radiology Department (Spain); Marras, Mariangela, E-mail: mariangela.marrasmd@gmail.com [Azienda Ospedaliero Brotzu (A.O.B.), Department of Radiology (Italy); Saba, Luca, E-mail: lucasaba@tiscali.it [Azienda Ospedaliero Universitaria (A.O.U.), Department of Radiology (Italy)

2016-09-15

ObjectiveThe purpose of this study was to assess, by the mean apparent diffusion coefficient (ADC), if a relationship exists between disc ADC and MR findings of adjacent disc degeneration after thoracolumbar fractures treated by anatomic reduction using vertebral augmentation (VAP).Materials and MethodsTwenty non-consecutive patients (mean age 50.7 years; range 45–56) treated because of vertebral fractures, were included in this study. There were 10 A3.1 and 10 A1.2 fractures (AO classification). Surgical treatment using VAP was applied in 14 cases, and conservative in 6 patients. MRI T2-weighted images and mapping of apparent diffusion coefficient (ADC) of the intervertebral disc adjacent to the fractured segment were performed after a mean follow-up of 32 months. A total of 60 discs, 3 per patient, were analysed: infra-adjacent, supra-adjacent and a control disc one level above the supra-adjacent.ResultsNo differences between patients surgically treated and those following a conservative protocol regarding the average ADC values obtained in the 20 control discs analysed were found. Considering all discs, average ADC in the supra-adjacent level was lower than in the infra-adjacent (1.35 ± 0.12 vs. 1.53 ± 0.06; p < 0.001). Average ADC values of the discs used as a control were similar to those of the infra-adjacent level (1.54 ± 0.06). Compared to surgically treated patients, discs at the supra-adjacent fracture level showed statistically significant lower values in cases treated conservatively (p < 0.001). The variation in the delay of surgery had no influence on the average values of ADC at any of the measured levels.ConclusionsADC measurements of the supra-adjacent discs after a mean follow-up of 32 months following thoracolumbar fractures, showed that restoration of the vertebral collapse by minimally invasive VAP prevents posttraumatic disc degeneration.

Extracellular matrix dynamics during vertebrate axis formation.

Science.gov (United States)

Czirók, András; Rongish, Brenda J; Little, Charles D

2004-04-01

The first evidence for the dynamics of in vivo extracellular matrix (ECM) pattern formation during embryogenesis is presented below. Fibrillin 2 filaments were tracked for 12 h throughout the avian intraembryonic mesoderm using automated light microscopy and algorithms of our design. The data show that these ECM filaments have a reproducible morphogenic destiny that is characterized by directed transport. Fibrillin 2 particles initially deposited in the segmental plate mesoderm are translocated along an unexpected trajectory where they eventually polymerize into an intricate scaffold of cables parallel to the anterior-posterior axis. The cables coalesce near the midline before the appearance of the next-formed somite. Moreover, the ECM filaments define global tissue movements with high precision because the filaments act as passive motion tracers. Quantification of individual and collective filament "behaviors" establish fate maps, trajectories, and velocities. These data reveal a caudally propagating traveling wave pattern in the morphogenetic movements of early axis formation. We conjecture that within vertebrate embryos, long-range mechanical tension fields are coupled to both large-scale patterning and local organization of the ECM. Thus, physical forces or stress fields are essential requirements for executing an emergent developmental pattern-in this case, paraxial fibrillin cable assembly.

Segmentation: Identification of consumer segments

DEFF Research Database (Denmark)

Høg, Esben

2005-01-01

It is very common to categorise people, especially in the advertising business. Also traditional marketing theory has taken in consumer segments as a favorite topic. Segmentation is closely related to the broader concept of classification. From a historical point of view, classification has its...... origin in other sciences as for example biology, anthropology etc. From an economic point of view, it is called segmentation when specific scientific techniques are used to classify consumers to different characteristic groupings. What is the purpose of segmentation? For example, to be able to obtain...... a basic understanding of grouping people. Advertising agencies may use segmentation totarget advertisements, while food companies may usesegmentation to develop products to various groups of consumers. MAPP has for example investigated the positioning of fish in relation to other food products...

Ancient duplications and functional divergence in the interferon regulatory factors of vertebrates provide insights into the evolution of vertebrate immune systems.

Science.gov (United States)

Du, Kang; Zhong, Zaixuan; Fang, Chengchi; Dai, Wei; Shen, Yanjun; Gan, Xiaoni; He, Shunping

2018-04-01

Interferon regulatory factors (IRFs) were first discovered as transcription factors that regulate the transcription of human interferon (IFN)-β. Increasing evidence shows that they might be important players involved in Adaptive immune system (AIS) evolution. Although numbers of IRFs have been identified in chordates, the evolutionary history and functional diversity of this gene family during the early evolution of vertebrates have remained obscure. Using IRF HMM profile and HMMER searches, we identified 148 IRFs in 11 vertebrates and 4 protochordates. For them, we reconstructed the phylogenetic relationships, determined the synteny conservation, investigated the profile of natural selection, and analyzed the expression patterns in four "living fossil" vertebrates: lamprey, elephant shark, coelacanth and bichir. The results from phylogeny and synteny analysis imply that vertebrate IRFs evolved from three predecessors, instead of four as suggested in a previous study, as results from an ancient duplication followed by special expansions and lost during the vertebrate evolution. The profile of natural selection and expression reveals functional dynamics during the process. Together, they suggest that the 2nd whole-genome duplication (2WGD) provided raw materials for innovation in the IRF family, and that the birth of type-I IFN might be an important factor inducing the establishment of IRF-mediated immune networks. As a member involved in the AIS evolution, IRF provide insights into the process and mechanism involved in the complexity and novelties of vertebrate immune systems. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Combined endovascular and surgical treatment in vertebral arteriovenous fistula

International Nuclear Information System (INIS)

Nakstad, P.H.; Haakonsen, M.; Magnaes, B.; Hetland, S.

1997-01-01

A 7-year-old girl with a right-sided congenital arteriovenous fistula in the neck was admitted with signs of cardial incompensation. Her fistula was fed from the right vertebral artery in antegrade as well as retrograde directions. A steal from the intracranial arteries was established. In addition, smaller feeding arteries from the neck were found. She was operated on with ligation of the right vertebral artery proximal to the fistula but the attempted ligation of the artery cranially to the fistula was unsuccessful. She was therefore embolized by the formation of a plug of platinum fiber coils in the upper right vertebral artery. Catheterization was performed from the left vertebral artery via the basilar artery. Persisting minor feeders to the fistula from cervical arteries were embolized in a second session. Finally, surgical extirpation of the fistula was performed together with the operative ligation of a crossover feeding artery from the left vertebral artery. Her heart size, heart rate and blood pressure were successively normalized. (orig.)

Evolutionary growth process of highly conserved sequences in vertebrate genomes.

Science.gov (United States)

Ishibashi, Minaka; Noda, Akiko Ogura; Sakate, Ryuichi; Imanishi, Tadashi

2012-08-01

Genome sequence comparison between evolutionarily distant species revealed ultraconserved elements (UCEs) among mammals under strong purifying selection. Most of them were also conserved among vertebrates. Because they tend to be located in the flanking regions of developmental genes, they would have fundamental roles in creating vertebrate body plans. However, the evolutionary origin and selection mechanism of these UCEs remain unclear. Here we report that UCEs arose in primitive vertebrates, and gradually grew in vertebrate evolution. We searched for UCEs in two teleost fishes, Tetraodon nigroviridis and Oryzias latipes, and found 554 UCEs with 100% identity over 100 bps. Comparison of teleost and mammalian UCEs revealed 43 pairs of common, jawed-vertebrate UCEs (jUCE) with high sequence identities, ranging from 83.1% to 99.2%. Ten of them retain lower similarities to the Petromyzon marinus genome, and the substitution rates of four non-exonic jUCEs were reduced after the teleost-mammal divergence, suggesting that robust conservation had been acquired in the jawed vertebrate lineage. Our results indicate that prototypical UCEs originated before the divergence of jawed and jawless vertebrates and have been frozen as perfect conserved sequences in the jawed vertebrate lineage. In addition, our comparative sequence analyses of UCEs and neighboring regions resulted in a discovery of lineage-specific conserved sequences. They were added progressively to prototypical UCEs, suggesting step-wise acquisition of novel regulatory roles. Our results indicate that conserved non-coding elements (CNEs) consist of blocks with distinct evolutionary history, each having been frozen since different evolutionary era along the vertebrate lineage. Copyright © 2012 Elsevier B.V. All rights reserved.

Closure of the vertebral canal in human embryos and fetuses

NARCIS (Netherlands)

Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S. Eleonore; Lamers, Wouter H.

2017-01-01

The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10weeks of

Gout and the Risk of Non-vertebral Fracture.

Science.gov (United States)

Kim, Seoyoung C; Paik, Julie M; Liu, Jun; Curhan, Gary C; Solomon, Daniel H

2017-02-01

Prior studies suggest an association between osteoporosis, systemic inflammation, and pro-inflammatory cytokines such as interleukin (IL)-1 and IL-6. Conflicting findings exist on the association between hyperuricemia and osteoporosis. Furthermore, it remains unknown whether gout, a common inflammatory arthritis, affects fracture risk. Using data from a US commercial health plan (2004-2013), we evaluated the risk of non-vertebral fracture (ie, forearm, wrist, hip, and pelvis) in patients with gout versus those without. Gout patients were identified with ≥2 diagnosis codes and ≥1 dispensing for a gout-related drug. Non-gout patients, identified with ≥2 visits coded for any diagnosis and ≥1 dispensing for any prescription drugs, were free of gout diagnosis and received no gout-related drugs. Hip fracture was the secondary outcome. Fractures were identified with a combination of diagnosis and procedure codes. Cox proportional hazards models compared the risk of non-vertebral fracture in gout patients versus non-gout, adjusting for more than 40 risk factors for osteoporotic fracture. Among gout patients with baseline serum uric acid (sUA) measurements available, we assessed the risk of non-vertebral fracture associated with sUA. We identified 73,202 gout and 219,606 non-gout patients, matched on age, sex, and the date of study entry. The mean age was 60 years and 82% were men. Over the mean 2-year follow-up, the incidence rate of non-vertebral fracture per 1,000 person-years was 2.92 in gout and 2.66 in non-gout. The adjusted hazard ratio (HR) was 0.98 (95% confidence interval [CI] 0.85-1.12) for non-vertebral fracture and 0.83 (95% CI 0.65-1.07) for hip fracture in gout versus non-gout. Subgroup analysis (n = 15,079) showed no association between baseline sUA and non-vertebral fracture (HR = 1.03, 95% CI 0.93-1.15), adjusted for age, sex, comorbidity score, and number of any prescription drugs. Gout was not associated with a risk of non-vertebral

Usher syndrome type 1-associated cadherins shape the photoreceptor outer segment.

Science.gov (United States)

Schietroma, Cataldo; Parain, Karine; Estivalet, Amrit; Aghaie, Asadollah; Boutet de Monvel, Jacques; Picaud, Serge; Sahel, José-Alain; Perron, Muriel; El-Amraoui, Aziz; Petit, Christine

2017-06-05

Usher syndrome type 1 (USH1) causes combined hearing and sight defects, but how mutations in USH1 genes lead to retinal dystrophy in patients remains elusive. The USH1 protein complex is associated with calyceal processes, which are microvilli of unknown function surrounding the base of the photoreceptor outer segment. We show that in Xenopus tropicalis , these processes are connected to the outer-segment membrane by links composed of protocadherin-15 (USH1F protein). Protocadherin-15 deficiency, obtained by a knockdown approach, leads to impaired photoreceptor function and abnormally shaped photoreceptor outer segments. Rod basal outer disks displayed excessive outgrowth, and cone outer segments were curved, with lamellae of heterogeneous sizes, defects also observed upon knockdown of Cdh23 , encoding cadherin-23 (USH1D protein). The calyceal processes were virtually absent in cones and displayed markedly reduced F-actin content in rods, suggesting that protocadherin-15-containing links are essential for their development and/or maintenance. We propose that calyceal processes, together with their associated links, control the sizing of rod disks and cone lamellae throughout their daily renewal. © 2017 Schietroma et al.

Vertebral split fractures: Technical feasibility of percutaneous vertebroplasty

Energy Technology Data Exchange (ETDEWEB)

Huwart, Laurent, E-mail: huwart.laurent@wanadoo.fr [Department of Radiology, Hôpital Archet 2, Centre Hospitalo-Universitaire de Nice, Nice (France); Foti, Pauline, E-mail: pfoti@hotmail.fr [Department of Biostatistics, Hôpital Archet 2, Centre Hospitalo-Universitaire de Nice, Nice (France); Andreani, Olivier, E-mail: andreani.olivier@gmail.com [Department of Radiology, Hôpital Archet 2, Centre Hospitalo-Universitaire de Nice, Nice (France); Hauger, Olivier, E-mail: olivier.hauger@chubordeaux.fr [Department of Radiology, Hôpital Pellegrin, Centre Hospitalo-Universitaire de Bordeaux, Bordeaux (France); Cervantes, Elodie, E-mail: elodie.cervantes@live.fr [Department of Radiology, Hôpital Archet 2, Centre Hospitalo-Universitaire de Nice, Nice (France); Brunner, Philippe, E-mail: pbrunner@chpg.mc [Department of Radiology, Hôpital Princesse Grasse de Monaco (Monaco); Boileau, Pascal, E-mail: boileau.p@chu-nice.fr [Department of Orthopedic Surgery, Hôpital Archet 2, Centre Hospitalo-Universitaire de Nice, Nice (France); Amoretti, Nicolas, E-mail: amorettinicolas@yahoo.fr [Department of Radiology, Hôpital Archet 2, Centre Hospitalo-Universitaire de Nice, Nice (France)

2014-01-15

Objective: The treatment of vertebral split fractures remains controversial, consisting of either corset or internal fixation. The aim of this study was to evaluate the technical feasibility of CT- and fluoroscopy-guided percutaneous vertebroplasty in the treatment of vertebral split fractures. Materials and methods: Institutional review board approval and informed consent were obtained for this study. Sixty-two consecutive adult patients who had post-traumatic vertebral split fractures (A2 according to the AO classification) without neurological symptoms were prospectively treated by percutaneous vertebroplasty. All these procedures were performed by an interventional radiologist under computed tomography (CT) and fluoroscopy guidance by using only local anaesthesia. Postoperative outcome was assessed using the visual analogue scale (VAS) and Oswestry disability index (ODI) scores. Results: Vertebroplasty was performed on thoracic and lumbar vertebrae, creating a cement bridge between the displaced fragment and the rest of the vertebral body. Seven discal cement leakages (11%) were observed, without occurrence of adjacent vertebral compression fractures. The mean VAS measurements ± standard deviation (SD) significantly decreased from 7.9 ± 1.5 preoperatively to 3.3 ± 2.1 at 1 day, 2.2 ± 2.0 at 1 month, and 1.8 ± 1.4 at 6 months (P < 0.001). The mean ODI scores ± SD had also a significant improvement: 62.3 ± 17.2 preoperatively and 15.1 ± 6.0 at the 6-month follow-up (P < 0.001). Conclusion: This study suggests that type A2 vertebral fractures could be successfully treated by CT- and fluoroscopy-guided percutaneous vertebroplasty.

Vertebral split fractures: Technical feasibility of percutaneous vertebroplasty

International Nuclear Information System (INIS)

Huwart, Laurent; Foti, Pauline; Andreani, Olivier; Hauger, Olivier; Cervantes, Elodie; Brunner, Philippe; Boileau, Pascal; Amoretti, Nicolas

2014-01-01

Objective: The treatment of vertebral split fractures remains controversial, consisting of either corset or internal fixation. The aim of this study was to evaluate the technical feasibility of CT- and fluoroscopy-guided percutaneous vertebroplasty in the treatment of vertebral split fractures. Materials and methods: Institutional review board approval and informed consent were obtained for this study. Sixty-two consecutive adult patients who had post-traumatic vertebral split fractures (A2 according to the AO classification) without neurological symptoms were prospectively treated by percutaneous vertebroplasty. All these procedures were performed by an interventional radiologist under computed tomography (CT) and fluoroscopy guidance by using only local anaesthesia. Postoperative outcome was assessed using the visual analogue scale (VAS) and Oswestry disability index (ODI) scores. Results: Vertebroplasty was performed on thoracic and lumbar vertebrae, creating a cement bridge between the displaced fragment and the rest of the vertebral body. Seven discal cement leakages (11%) were observed, without occurrence of adjacent vertebral compression fractures. The mean VAS measurements ± standard deviation (SD) significantly decreased from 7.9 ± 1.5 preoperatively to 3.3 ± 2.1 at 1 day, 2.2 ± 2.0 at 1 month, and 1.8 ± 1.4 at 6 months (P < 0.001). The mean ODI scores ± SD had also a significant improvement: 62.3 ± 17.2 preoperatively and 15.1 ± 6.0 at the 6-month follow-up (P < 0.001). Conclusion: This study suggests that type A2 vertebral fractures could be successfully treated by CT- and fluoroscopy-guided percutaneous vertebroplasty

Contaminant exposure in terrestrial vertebrates

International Nuclear Information System (INIS)

Smith, Philip N.; Cobb, George P.; Godard-Codding, Celine; Hoff, Dale; McMurry, Scott T.; Rainwater, Thomas R.; Reynolds, Kevin D.

2007-01-01

Here we review mechanisms and factors influencing contaminant exposure among terrestrial vertebrate wildlife. There exists a complex mixture of biotic and abiotic factors that dictate potential for contaminant exposure among terrestrial and semi-terrestrial vertebrates. Chemical fate and transport in the environment determine contaminant bioaccessibility. Species-specific natural history characteristics and behavioral traits then play significant roles in the likelihood that exposure pathways, from source to receptor, are complete. Detailed knowledge of natural history traits of receptors considered in conjunction with the knowledge of contaminant behavior and distribution on a site are critical when assessing and quantifying exposure. We review limitations in our understanding of elements of exposure and the unique aspects of exposure associated with terrestrial and semi-terrestrial taxa. We provide insight on taxa-specific traits that contribute, or limit exposure to, transport phenomenon that influence exposure throughout terrestrial systems, novel contaminants, bioavailability, exposure data analysis, and uncertainty associated with exposure in wildlife risk assessments. Lastly, we identify areas related to exposure among terrestrial and semi-terrestrial organisms that warrant additional research. - Both biotic and abiotic factors determine chemical exposure for terrestrial vertebrates

Rhodopsin Forms Nanodomains in Rod Outer Segment Disc Membranes of the Cold-Blooded Xenopus laevis.

Directory of Open Access Journals (Sweden)

Tatini Rakshit

Full Text Available Rhodopsin forms nanoscale domains (i.e., nanodomains in rod outer segment disc membranes from mammalian species. It is unclear whether rhodopsin arranges in a similar manner in amphibian species, which are often used as a model system to investigate the function of rhodopsin and the structure of photoreceptor cells. Moreover, since samples are routinely prepared at low temperatures, it is unclear whether lipid phase separation effects in the membrane promote the observed nanodomain organization of rhodopsin from mammalian species. Rod outer segment disc membranes prepared from the cold-blooded frog Xenopus laevis were investigated by atomic force microscopy to visualize the organization of rhodopsin in the absence of lipid phase separation effects. Atomic force microscopy revealed that rhodopsin nanodomains form similarly as that observed previously in mammalian membranes. Formation of nanodomains in ROS disc membranes is independent of lipid phase separation and conserved among vertebrates.

Use of cervical vertebral dimensions for assessment of children growth

Directory of Open Access Journals (Sweden)

Maria de Paula Caldas

2007-04-01

Full Text Available OBJECTIVE: The purpose of this study was to investigate whether skeletal maturation using cephalometric radiographs could be used in a Brazilian population. MATERIAL AND METHODS: The study population was selected from the files of the Oral Radiological Clinic of the Dental School of Piracicaba, Brazil and consisted of 128 girls and 110 boys (7.0 to 15.9 years old who had cephalometric and hand-wrist radiographs taken on the same day. Cervical vertebral bone age was evaluated using the method described by Mito and colleagues in 2002. Bone age was assessed by the Tanner-Whitehouse (TW3 method and was used as a gold standard to determine the reliability of cervical vertebral bone age. An analysis of variance and Tukey's post-hoc test were used to compare cervical vertebral bone age, bone age and chronological age at 5% significance level. RESULTS: The analysis of the Brazilian female children data showed that there was a statistically significant difference (p0.05 was found between cervical vertebral bone age and bone age. Differently, the analysis of the male children data revealed a statistically significant difference (p<0.05 between cervical vertebral bone age and bone age and between cervical vertebral bone age and chronological age (p<0.05. CONCLUSIONS: The findings of the present study suggest that the method for objectively evaluating skeletal maturation on cephalometric radiographs by determination of vertebral bone age can be applied to Brazilian females only. The development of a new method to objectively evaluate cervical vertebral bone age in males is needed.

Allergenicity of vertebrate tropomyosins: Challenging an immunological dogma.

Science.gov (United States)

González-Fernández, J; Daschner, A; Cuéllar, C

With the exception of tilapia tropomyosin, other anecdotic reports of tropomyosin recognition of vertebrate origin are generally not accompanied by clinical significance and a dogmatic idea is generally accepted about the inexistence of allergenicity of vertebrate tropomyosins, based mainly on sequence similarity evaluations with human tropomyosins. Recently, a specific work-up of a tropomyosin sensitised patient with seafood allergy, demonstrated that the IgE-recognition of tropomyosin from different fish species can be clinically relevant. We hypothesise that some vertebrate tropomyosins could be relevant allergens. The hypothesis is based on the molecular evolution of the proteins and it was tested by in silico methods. Fish, which are primitive vertebrates, could have tropomyosins similar to those of invertebrates. If the hypothesis is confirmed, tropomyosin should be included in different allergy diagnosis tools to improve the medical protocols and management of patients with digestive or cutaneous symptoms after fish intake. Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

Cervical vertebral and dental maturity in Turkish subjects.

Science.gov (United States)

Başaran, Güvenç; Ozer, Törün; Hamamci, Nihal

2007-04-01

The aim of this study was to investigate the relationships between the stages of calcification of teeth and the cervical vertebral maturity stages in Turkish subjects. A retrospective cross-sectional study was designed. The final study population consisted of 590 Turkish subjects. Statistical analysis of the data was performed with computer software. Spearman rank order correlation coefficients were used to assess the relationship between cervical vertebral and dental maturation. For a better understanding of the relationship between cervical vertebral maturation indexes and dental age, percentage distributions of the studied teeth were also calculated. Strict correlations were found between dental and cervical vertebral maturation of Turkish subjects. For males, the sequence from lowest to the highest was third molar, central incisor, canine, first premolar, second premolar, first molar, and second molar. For females, the sequence from lowest to the highest was third molar, canine, second premolar, first premolar, central incisor, first molar, and second molar. Dental maturation stages can be used as a reliable indicator of facial growth.

Corticotropin-releasing hormone: Mediator of vertebrate life stage transitions?

Science.gov (United States)

Watanabe, Yugo; Grommen, Sylvia V H; De Groef, Bert

2016-03-01

Hormones, particularly thyroid hormones and corticosteroids, play critical roles in vertebrate life stage transitions such as amphibian metamorphosis, hatching in precocial birds, and smoltification in salmonids. Since they synergistically regulate several metabolic and developmental processes that accompany vertebrate life stage transitions, the existence of extensive cross-communication between the adrenal/interrenal and thyroidal axes is not surprising. Synergies of corticosteroids and thyroid hormones are based on effects at the level of tissue hormone sensitivity and gene regulation. In addition, in representative nonmammalian vertebrates, corticotropin-releasing hormone (CRH) stimulates hypophyseal thyrotropin secretion, and thus functions as a common regulator of both the adrenal/interrenal and thyroidal axes to release corticosteroids and thyroid hormones. The dual function of CRH has been speculated to control or affect the timing of vertebrate life history transitions across taxa. After a brief overview of recent insights in the molecular mechanisms behind the synergic actions of thyroid hormones and corticosteroids during life stage transitions, this review examines the evidence for a possible role of CRH in controlling vertebrate life stage transitions. Copyright © 2016 Elsevier Inc. All rights reserved.

Excessive Daytime Sleepiness

Directory of Open Access Journals (Sweden)

Yavuz Selvi

2016-06-01

Full Text Available Excessive daytime sleepiness is one of the most common sleep-related patient symptoms, with preva-lence in the community estimated to be as high as 18%. Patients with excessive daytime sleepiness may exhibit life threatening road and work accidents, social maladjustment, decreased academic and occupational performance and have poorer health than comparable adults. Thus, excessive daytime sleepiness is a serious condition that requires investigation, diagnosis and treatment primarily. As with most medical condition, evaluation of excessive daytime sleepiness begins a precise history and various objective and subjective tools have been also developed to assess excessive daytime sleepiness. The most common causes of excessive daytime sleepiness are insufficient sleep hygiene, chronic sleep deprivation, medical and psychiatric conditions and sleep disorders, such as obstructive sleep apnea, medications, and narcolepsy. Treatment option should address underlying contributors and promote sleep quantity by ensuring good sleep hygiene. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(2: 114-132

Cause analysis of missing diagnosis for vertebral fracture on lateral chest radiography

International Nuclear Information System (INIS)

Yu Wei; Yao Jinpeng; Lin Qiang; Mu Wenbin

2010-01-01

Objective: To analyze the cause of missing diagnosis for vertebral fracture on lateral chest radiography. Methods: Lateral chest radiographies of 1638 hospitalized patients (871 males and 767 females) were retrospectively reviewed for identifying vertebral fractures. Their ages ranged from 50 to 91 years with the mean of 63.5 years. Complains and application for chest radiography in all patients were not related to osteoporosis and vertebral fracture. Vertebral fracture and fracture severity were evaluated using Genant's semiquantitative visual method, taking approximately a 20%-25% vertebral height reduction as mild grade, 26%--40% as moderate grade and 41% or greater as severe grade. Evaluation results of the vertebral fracture, original X-ray reports, as well as medical records were compared for further analysis. Results: Eighty-four in 1638 patients showed vertebral fractures on the lateral chest radiographies. Of them, vertebral fractures were reported in 30 cases and 54 patients were not reported on their original X-ray reports. There were 63 vertebral fractures in 54 un-reported patients, most of which were single fracture (75% or 47/63). Grade I fracture accounted for 54% (34/63), Grade II fracture 33% (21/63), while 13% presented grade III fracture (8/63). In all 84 patients with vertebral fractures, only 5 cases (6%) underwent dual energy X-ray absorptiometry (DXA) measurement, 5 cases (6%) were recorded to have vertebral fractures on the medical papers, as well as 15 cases (18%) were prescribed drugs related to the osteoporosis when discharged from hospital. All drugs prescribed for the 15 patients were limited only to calcium. Conclusions: More attention should be paid to osteoporosis by doctors including radiologists. Vertebral fracture on lateral chest radiography should be completely diagnosed, which is helpful for both prevention and treatment. (authors)

Under-reporting of osteoporotic vertebral fractures on computed tomography

International Nuclear Information System (INIS)

Williams, Alexandra L.; Al-Busaidi, Aisha; Sparrow, Patrick J.; Adams, Judith E.; Whitehouse, Richard W.

2009-01-01

Purpose: Osteoporotic vertebral fractures are frequently asymptomatic. They are often not diagnosed clinically or radiologically. Despite this, prevalent osteoporotic vertebral fractures predict future osteoporotic fractures and are associated with increased mortality and morbidity. Appropriate management of osteoporosis can reduce future fracture risk. Fractures on lateral chest radiographs taken for other conditions are frequently overlooked by radiologists. Our aim was to assess the value of computed tomography (CT) in the diagnosis of vertebral fracture and identify the frequency with which significant fractures are missed. Materials and methods: The thoracic CT scans of 100 consecutive male and 100 consecutive female patients over 55 years were reviewed. CT images were acquired on General Electric Lightspeed multi-detector (MD) CT scanners (16 or 32 row) using 1.25 mm slice thickness. Midline sagittal images were reconstructed from the 3D volume images. The presence of moderate (25-40% height loss) or severe (>40% height loss) vertebral fractures between T1 and L1 was determined using an established semi-quantitative method and confirmed by morphological measurement. Results were compared with the formal CT report. Results: Scans of 192 patients were analysed (95 female; 97 male); mean age 70.1 years. Thirty-eight (19.8%) patients had one or more moderate to severe vertebral fractures. Only 5 (13%) were correctly reported as having osteoporotic fractures in the official report. The sensitivity of axial CT images to vertebral fracture was 0.35. Conclusion: Incidental osteoporotic vertebral fractures are under-reported on CT. The sensitivity of axial images in detecting these fractures is poor. Sagittal reformations are strongly recommended to improve the detection rate

Cochlear vertebral entrapment syndrome: a case report

Energy Technology Data Exchange (ETDEWEB)

Liu Chinghsiung; Lin Shinnkuang E-mail: sk1943@adm.cgmh.org.tw; Chang Yeujhy

2001-11-01

The authors describe a patient with isolated involvement of vestibulocochlear nerve by a huge vascular loop from vertebral dolichoectasia. No other neurological deficit was found except for unilateral hearing loss. Abnormal brainstem auditory evoked potential study indicated a retrocochlear lesion. The brain computed tomography (CT) and magnetic resonance imaging (MRI) studies demonstrated an abnormally enhanced vascular lesion impinged on the left porus acusticus with a displacement of the brainstem to the right. There was no infarction in the brainstem. A cerebral angiography demonstrated a megadolichoectatic horizontal loop at the intracranial portion of the left vertebral artery. There was no thrombus or atherosclerosis in the vertebrobasilar system. A mechanical compression by a vascular loop is the only possible pathogenesis for hearing loss. The authors diagnose this condition as cochlear vertebral entrapment syndrome.

Imperfect Isolation: Factors and Filters Shaping Madagascar’s Extant Vertebrate Fauna

Science.gov (United States)

Samonds, Karen E.; Godfrey, Laurie R.; Ali, Jason R.; Goodman, Steven M.; Vences, Miguel; Sutherland, Michael R.; Irwin, Mitchell T.; Krause, David W.

2013-01-01

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar’s colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island’s biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island’s paleogeographical evolution to determine how particular events influenced the arrival of the island’s extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar’s tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island’s isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar’s extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar’s unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of

A comparative meta-analysis of maximal aerobic metabolism of vertebrates: implications for respiratory and cardiovascular limits to gas exchange.

Science.gov (United States)

Hillman, Stanley S; Hancock, Thomas V; Hedrick, Michael S

2013-02-01

Maximal aerobic metabolic rates (MMR) in vertebrates are supported by increased conductive and diffusive fluxes of O(2) from the environment to the mitochondria necessitating concomitant increases in CO(2) efflux. A question that has received much attention has been which step, respiratory or cardiovascular, provides the principal rate limitation to gas flux at MMR? Limitation analyses have principally focused on O(2) fluxes, though the excess capacity of the lung for O(2) ventilation and diffusion remains unexplained except as a safety factor. Analyses of MMR normally rely upon allometry and temperature to define these factors, but cannot account for much of the variation and often have narrow phylogenetic breadth. The unique aspect of our comparative approach was to use an interclass meta-analysis to examine cardio-respiratory variables during the increase from resting metabolic rate to MMR among vertebrates from fish to mammals, independent of allometry and phylogeny. Common patterns at MMR indicate universal principles governing O(2) and CO(2) transport in vertebrate cardiovascular and respiratory systems, despite the varied modes of activities (swimming, running, flying), different cardio-respiratory architecture, and vastly different rates of metabolism (endothermy vs. ectothermy). Our meta-analysis supports previous studies indicating a cardiovascular limit to maximal O(2) transport and also implicates a respiratory system limit to maximal CO(2) efflux, especially in ectotherms. Thus, natural selection would operate on the respiratory system to enhance maximal CO(2) excretion and the cardiovascular system to enhance maximal O(2) uptake. This provides a possible evolutionary explanation for the conundrum of why the respiratory system appears functionally over-designed from an O(2) perspective, a unique insight from previous work focused solely on O(2) fluxes. The results suggest a common gas transport blueprint, or Bauplan, in the vertebrate clade.

Association between vertebral cross-sectional area and lumbar lordosis angle in adolescents.

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Tishya A L Wren

Full Text Available Lumbar lordosis (LL is more prominent in women than in men, but the mechanisms responsible for this discrepancy are poorly defined. A recent study indicates that newborn girls have smaller vertebral cross-sectional area (CSA when compared to boys-a difference that persists throughout life and is independent of body size. We determined the relations between vertebral cross-sectional area (CSA and LL angle and whether sex differences in lumbar lordosis are related to sex differences in vertebral CSA. Using multi-planar magnetic resonance imaging (MRI, we measured vertebral cross-sectional area (CSA and vertebral height of the spine of 40 healthy boys and 40 girls, ages 9-13 years. Measures of the CSA of the lumbar vertebrae significantly differed between sexes (9.38 ± 1.46 vs. 7.93 ± 0.69 in boys and girls, respectively; P < 0.0001, while the degree of LL was significantly greater in girls than in boys (23.7 ± 6.1 vs. 27.6 ± 8.0 in boys and girls, respectively; P = 0.02. When all subjects were analyzed together, values for LL angle were negatively correlated to vertebral CSA (r = -0.47; P < 0.0001; this was also true when boys and girls were analyzed separately. Multivariate regression analysis indicated that vertebral CSA was independently associated with LL, even after accounting for sex, age, height or vertebral height, and weight. Similar negative relations were present when thoracic vertebrae were analyzed (Model P < 0.0001, R2 = 0.37, thoracic vertebral CSA slope P < 0.0001, suggesting that deficient vertebral cross-sectional dimensions are not merely the consequence of the anterior lumbar curvature. We conclude that vertebral CSA is negatively associated with LL, and that the greater degree of LL in females could, at least in part, be due to smaller vertebral cross-sectional dimensions. Studies are needed to examine the potential relations between vertebral CSA and spinal conditions known to be associated with increased LL, such as

Association between vertebral cross-sectional area and lumbar lordosis angle in adolescents.

Science.gov (United States)

Wren, Tishya A L; Aggabao, Patricia C; Poorghasamians, Ervin; Chavez, Thomas A; Ponrartana, Skorn; Gilsanz, Vicente

2017-01-01

Lumbar lordosis (LL) is more prominent in women than in men, but the mechanisms responsible for this discrepancy are poorly defined. A recent study indicates that newborn girls have smaller vertebral cross-sectional area (CSA) when compared to boys-a difference that persists throughout life and is independent of body size. We determined the relations between vertebral cross-sectional area (CSA) and LL angle and whether sex differences in lumbar lordosis are related to sex differences in vertebral CSA. Using multi-planar magnetic resonance imaging (MRI), we measured vertebral cross-sectional area (CSA) and vertebral height of the spine of 40 healthy boys and 40 girls, ages 9-13 years. Measures of the CSA of the lumbar vertebrae significantly differed between sexes (9.38 ± 1.46 vs. 7.93 ± 0.69 in boys and girls, respectively; P < 0.0001), while the degree of LL was significantly greater in girls than in boys (23.7 ± 6.1 vs. 27.6 ± 8.0 in boys and girls, respectively; P = 0.02). When all subjects were analyzed together, values for LL angle were negatively correlated to vertebral CSA (r = -0.47; P < 0.0001); this was also true when boys and girls were analyzed separately. Multivariate regression analysis indicated that vertebral CSA was independently associated with LL, even after accounting for sex, age, height or vertebral height, and weight. Similar negative relations were present when thoracic vertebrae were analyzed (Model P < 0.0001, R2 = 0.37, thoracic vertebral CSA slope P < 0.0001), suggesting that deficient vertebral cross-sectional dimensions are not merely the consequence of the anterior lumbar curvature. We conclude that vertebral CSA is negatively associated with LL, and that the greater degree of LL in females could, at least in part, be due to smaller vertebral cross-sectional dimensions. Studies are needed to examine the potential relations between vertebral CSA and spinal conditions known to be associated with increased LL, such as spondylolysis

Pleistocene vertebrates of the Yukon Territory

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Harington, C. R.

2011-08-01

Unglaciated parts of the Yukon constitute one of the most important areas in North America for yielding Pleistocene vertebrate fossils. Nearly 30 vertebrate faunal localities are reviewed spanning a period of about 1.6 Ma (million years ago) to the close of the Pleistocene some 10 000 BP (radiocarbon years before present, taken as 1950). The vertebrate fossils represent at least 8 species of fishes, 1 amphibian, 41 species of birds and 83 species of mammals. Dominant among the large mammals are: steppe bison ( Bison priscus), horse ( Equus sp.), woolly mammoth ( Mammuthus primigenius), and caribou ( Rangifer tarandus) - signature species of the Mammoth Steppe fauna ( Fig. 1), which was widespread from the British Isles, through northern Europe, and Siberia to Alaska, Yukon and adjacent Northwest Territories. The Yukon faunas extend from Herschel Island in the north to Revenue Creek in the south and from the Alaskan border in the west to Ketza River in the east. The Yukon holds evidence of the earliest-known people in North America. Artifacts made from bison, mammoth and caribou bones from Bluefish Caves, Old Crow Basin and Dawson City areas show that people had a substantial knowledge of making and using bone tools at least by 25 000 BP, and possibly as early as 40 000 BP. A suggested chronological sequence of Yukon Pleistocene vertebrates ( Table 1) facilitates comparison of selected faunas and indicates the known duration of various taxa.

Magnetic resonance angiography of the extracranial carotid and vertebral arteries

International Nuclear Information System (INIS)

Akimura, Tatsuo; Saito, Kenichi; Nakayama, Hisato; Kashiwagi, Shiro; Kato, Shoichi; Ito, Haruhide.

1994-01-01

To evaluate the contribution of magnetic resonance angiography (MRA) in the screening study of the extracranial carotid and vertebral arteries using the conventional head and neck coils, 500 consecutive MRAs of the cervical vessels were performed using 1.5 tesla magnetic resonance unit with circularly polarized head coil. The 5 cm-thick imaging plane was placed in coronal fashion including both carotid and vertebral arteries. The imaging sequence was three-dimensional (3D) fast imaging with steady precession (FISP). In 10 patients with failed head coil examination, 10 patients with possible carotid and vertebral diseases and 10 volunteers, the extracranial carotid and vertebral arteries were examined with the Helmholtz neck coil. Both 3D- and 2D-FISP were performed in each case. The imaging plane was placed in oblique sagittal fashion. In 458 out of 500 cases (91.6%), the extracranial carotid and vertebral arteries were successfully depicted using head coil. In 20 patients with high shoulders, the carotid bifurcations were out of range of the head coil. In these cases, carotid bifurcations and the origins of the carotid and vertebral arteries were successfully revealed using a neck coil. To evaluate the stenotic lesions and tortuous vessels, 2D-FISP sequence seemed to be more suitable than 3D-FISP. Compared with conventional angiography, MRA caused overestimation of the degree of stenotic lesions. For screening examination of the extracranial carotid and vertebral arteries, most cases can be evaluated only with the conventional head coil. If depiction of the carotid bifurcation fails and the examination of carotids or vertebrals down to the aortic arch is needed, neck coil examination is required. (author)

The biogeography of threatened insular iguanas and opportunities for invasive vertebrate management

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Tershy, Bernie R.; Newton, Kelly M.; Spatz, Dena R.; Swinnerton, Kirsty; Iverson, John B.; Fisher, Robert N.; Harlow, Peter S.; Holmes, Nick D.; Croll, Donald A.; Iverson, J.B.; Grant, T. D.; Knapp, C. R.; Pasachnik, S. A.

2016-01-01

Iguanas are a particularly threatened group of reptiles, with 61% of species at risk of extinction. Primary threats to iguanas include habitat loss, direct and indirect impacts by invasive vertebrates, overexploitation, and human disturbance. As conspicuous, charismatic vertebrates, iguanas also represent excellent flagships for biodiversity conservation. To assist planning for invasive vertebrate management and thus benefit threatened iguana recovery, we identified all islands with known extant or extirpated populations of Critically Endangered and Endangered insular iguana taxa as recognized by the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. For each island, we determined total area, sovereignty, the presence of invasive alien vertebrates, and human population. For the 23 taxa of threatened insular iguanas we identified 230 populations, of which iguanas were extant on 185 islands and extirpated from 45 islands. Twenty-one iguana taxa (91% of all threatened insular iguana taxa) occurred on at least one island with invasive vertebrates present; 16 taxa had 100% of their population(s) on islands with invasive vertebrates present. Rodents, cats, ungulates, and dogs were the most common invasive vertebrates. We discuss biosecurity, eradication, and control of invasive vertebrates to benefit iguana recovery: (1) on islands already free of invasive vertebrates; (2) on islands with high iguana endemicity; and (3) for species and subspecies with small total populations occurring across multiple small islands. Our analyses provide an important first step toward understanding how invasive vertebrate management can be planned effectively to benefit threatened insular iguanas.

Zygotic Genome Activation in Vertebrates.

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Jukam, David; Shariati, S Ali M; Skotheim, Jan M

2017-08-21

The first major developmental transition in vertebrate embryos is the maternal-to-zygotic transition (MZT) when maternal mRNAs are degraded and zygotic transcription begins. During the MZT, the embryo takes charge of gene expression to control cell differentiation and further development. This spectacular organismal transition requires nuclear reprogramming and the initiation of RNAPII at thousands of promoters. Zygotic genome activation (ZGA) is mechanistically coordinated with other embryonic events, including changes in the cell cycle, chromatin state, and nuclear-to-cytoplasmic component ratios. Here, we review progress in understanding vertebrate ZGA dynamics in frogs, fish, mice, and humans to explore differences and emphasize common features. Copyright © 2017 Elsevier Inc. All rights reserved.

Relevant signs of stable and unstable thoracolumbar vertebral column trauma

International Nuclear Information System (INIS)

Gehweiler, J.A.; Daffner, R.H.; Osborne, R.L.

1981-01-01

One-hundred and seventeen patients with acute thoracolumbar vertebral column fracture or fracture-dislocations were analyzed and classified into stable (36%) and unstable (64%). Eight helpful roentgen signs were observed that may serve to direct attention to serious underlying, often occult, fractures and dislocations. The changes fall into four principal groups: abnormal soft tissues, abnormal vertebral alignment, abnormal joints, and widened vertebral canal. All stable and unstable lesions showed abnormal soft tissues, while 70% demonstrated kyphosis and/or scoliosis, and an abnormal adjacent intervertebral disk space. All unstable lesions showed one or more of the following signs: displaced vertebra, widened interspinous space, abnormal apophyseal joint(s), and widened vertebral canal. (orig.)

Status of the segment interconnect, cable segment ancillary logic, and the cable segment hybrid driver projects

International Nuclear Information System (INIS)

Swoboda, C.; Barsotti, E.; Chappa, S.; Downing, R.; Goeransson, G.; Lensy, D.; Moore, G.; Rotolo, C.; Urish, J.

1985-01-01

The FASTBUS Segment Interconnect (SI) provides a communication path between two otherwise independent, asynchronous bus segments. In particular, the Segment Interconnect links a backplane crate segment to a cable segment. All standard FASTBUS address and data transactions can be passed through the SI or any number of SIs and segments in a path. Thus systems of arbitrary connection complexity can be formed, allowing simultaneous independent processing, yet still permitting devices associated with one segment to be accessed from others. The model S1 Segment Interconnect and the Cable Segment Ancillary Logic covered in this report comply with all the mandatory features stated in the FASTBUS specification document DOE/ER-0189. A block diagram of the SI is shown

Population segmentation: an approach to reducing childhood obesity inequalities.

Science.gov (United States)

Mahmood, Hashum; Lowe, Susan

2017-05-01

The aims of this study are threefold: (1) to investigate the relationship between socio-economic status (inequality) and childhood obesity prevalence within Birmingham local authority, (2) to identify any change in childhood obesity prevalence between deprivation quintiles and (3) to analyse individualised Birmingham National Child Measurement Programme (NCMP) data using a population segmentation tool to better inform obesity prevention strategies. Data from the NCMP for Birmingham (2010/2011 and 2014/2015) were analysed using the deprivation scores from the Income Domain Affecting Children Index (IDACI 2010). The percentage of children with excess weight was calculated for each local deprivation quintile. Population segmentation was carried out using the Experian's Mosaic Public Sector 6 (MPS6) segmentation tool. Childhood obesity levels have remained static at the national and Birmingham level. For Year 6 pupils, obesity levels have increased in the most deprived deprivation quintiles for boys and girls. The most affluent quintile shows a decreasing trend of obesity prevalence for boys and girls in both year groups. For the middle quintiles, the results show fluctuating trends. This research highlighted the link in Birmingham between obesity and socio-economic factors with the gap increasing between deprivation quintiles. Obesity is a complex problem that cannot simply be addressed through targeting most deprived populations, rather through a range of effective interventions tailored for the various population segments that reside within communities. Using population segmentation enables a more nuanced understanding of the potential barriers and levers within populations on their readiness for change. The segmentation of childhood obesity data will allow utilisation of social marketing methodology that will facilitate identification of suitable methods for interventions and motivate individuals to sustain behavioural change. Sequentially, it will also inform

Common metabolic constraints on dive duration in endothermic and ectothermic vertebrates

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April Hayward

2016-10-01

Full Text Available Dive duration in air-breathing vertebrates is thought to be constrained by the volume of oxygen stored in the body and the rate at which it is consumed (i.e., “oxygen store/usage hypothesis”. The body mass-dependence of dive duration among endothermic vertebrates is largely supportive of this model, but previous analyses of ectothermic vertebrates show no such body mass-dependence. Here we show that dive duration in both endotherms and ectotherms largely support the oxygen store/usage hypothesis after accounting for the well-established effects of temperature on oxygen consumption rates. Analyses of the body mass and temperature dependence of dive duration in 181 species of endothermic vertebrates and 29 species of ectothermic vertebrates show that dive duration increases as a power law with body mass, and decreases exponentially with increasing temperature. Thus, in the case of ectothermic vertebrates, changes in environmental temperature will likely impact the foraging ecology of divers.

Closure of the vertebral canal in human embryos and fetuses.

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Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S Eleonore; Lamers, Wouter H

2017-08-01

The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10 weeks of development. Human embryos (5-10 weeks of development) were visualized using Amira 3D ® reconstruction and Cinema 4D ® remodelling software. Vertebral bodies were identifiable as loose mesenchymal structures between the dense mesenchymal intervertebral discs up to 6 weeks and then differentiated into cartilaginous structures in the 7th week. In this week, the dense mesenchymal neural processes also differentiated into cartilaginous structures. Transverse processes became identifiable at 6 weeks. The growth rate of all vertebral bodies was exponential and similar between 6 and 10 weeks, whereas the intervertebral discs hardly increased in size between 6 and 8 weeks and then followed vertebral growth between 8 and 10 weeks. The neural processes extended dorsolaterally (6th week), dorsally (7th week) and finally dorsomedially (8th and 9th weeks) to fuse at the midthoracic level at 9 weeks. From there, fusion extended cranially and caudally in the 10th week. Closure of the foramen magnum required the development of the supraoccipital bone as a craniomedial extension of the exoccipitals (neural processes of occipital vertebra 4), whereas a growth burst of sacral vertebra 1 delayed closure until 15 weeks. Both the cranial- and caudal-most vertebral bodies fused to form the basioccipital (occipital vertebrae 1-4) and sacrum (sacral vertebrae 1-5). In the sacrum, fusion of its so-called alar processes preceded that of the bodies by at least 6 weeks. In conclusion, the highly ordered and substantial changes in shape of the vertebral bodies leading to the formation of the vertebral canal make the development of the spine an excellent, continuous staging system for

LncRNAs in vertebrates: advances and challenges.

Science.gov (United States)

Mallory, Allison C; Shkumatava, Alena

2015-10-01

Beyond the handful of classic and well-characterized long noncoding RNAs (lncRNAs), more recently, hundreds of thousands of lncRNAs have been identified in multiple species including bacteria, plants and vertebrates, and the number of newly annotated lncRNAs continues to increase as more transcriptomes are analyzed. In vertebrates, the expression of many lncRNAs is highly regulated, displaying discrete temporal and spatial expression patterns, suggesting roles in a wide range of developmental processes and setting them apart from classic housekeeping ncRNAs. In addition, the deregulation of a subset of these lncRNAs has been linked to the development of several diseases, including cancers, as well as developmental anomalies. However, the majority of vertebrate lncRNA functions remain enigmatic. As such, a major task at hand is to decipher the biological roles of lncRNAs and uncover the regulatory networks upon which they impinge. This review focuses on our emerging understanding of lncRNAs in vertebrate animals, highlighting some recent advances in their functional analyses across several species and emphasizing the current challenges researchers face to characterize lncRNAs and identify their in vivo functions. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Body Composition Assessment in Axial CT Images Using FEM-Based Automatic Segmentation of Skeletal Muscle.

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Popuri, Karteek; Cobzas, Dana; Esfandiari, Nina; Baracos, Vickie; Jägersand, Martin

2016-02-01

The proportions of muscle and fat tissues in the human body, referred to as body composition is a vital measurement for cancer patients. Body composition has been recently linked to patient survival and the onset/recurrence of several types of cancers in numerous cancer research studies. This paper introduces a fully automatic framework for the segmentation of muscle and fat tissues from CT images to estimate body composition. We developed a novel finite element method (FEM) deformable model that incorporates a priori shape information via a statistical deformation model (SDM) within the template-based segmentation framework. The proposed method was validated on 1000 abdominal and 530 thoracic CT images and we obtained very good segmentation results with Jaccard scores in excess of 90% for both the muscle and fat regions.

Vertebral physitis: a radiographic diagnosis to be separated from discospondylitis: a preliminary report

International Nuclear Information System (INIS)

Jimenez, M.M.; O'Callaghan, M.W.

1995-01-01

A retrospective study was initiated to investigate the incidence, radiographic appearance and progression of vertebral physitis, a condition the authors propose as a separate radiographic diagnosis from discospondylitis. From 30 dogs with an initial radiographic diagnosis of discospondylitis, six dogs (five less than two years old) had radiographic signs believed to represent vertebral physitis. Bone lysis initially confined to the caudal physeal zone of affected vertebrae and sparing the vertebral endplates characterized the vertebral physitis lesions. Subsequent collapse of the caudoventral vertebral body and reactive spondylosis arising only from the caudal vertebral margins followed as the lesions progressed. By contrast, discospondylitis lesions originated as symmetric lysis of the vertebral endplates with reactive sclerosis in both vertebral bodies, and subsequent symmetric spondylosis. As a result of the differing radiographic patterns demonstrated by the physitis and discospondylitis lesions the author's also propose an alternative pathogenesis from that which is generally accepted for discospondylitis

Imaging of vertebral trauma

International Nuclear Information System (INIS)

Daffner, R.H.

1999-01-01

This translation of the toolbook published in the 'US-ART' series, offers invaluable help to medical radiologists in the diagnostic imaging and evaluation of complex vertebral traumas which are on the rise, inter alia due to increasingly dangerous leisure sports. (orig./CB) [de

Insights from amphioxus into the evolution of vertebrate cartilage.

Directory of Open Access Journals (Sweden)

Daniel Meulemans

2007-08-01

Full Text Available Central to the story of vertebrate evolution is the origin of the vertebrate head, a problem difficult to approach using paleontology and comparative morphology due to a lack of unambiguous intermediate forms. Embryologically, much of the vertebrate head is derived from two ectodermal tissues, the neural crest and cranial placodes. Recent work in protochordates suggests the first chordates possessed migratory neural tube cells with some features of neural crest cells. However, it is unclear how and when these cells acquired the ability to form cellular cartilage, a cell type unique to vertebrates. It has been variously proposed that the neural crest acquired chondrogenic ability by recruiting proto-chondrogenic gene programs deployed in the neural tube, pharynx, and notochord. To test these hypotheses we examined the expression of 11 amphioxus orthologs of genes involved in neural crest chondrogenesis. Consistent with cellular cartilage as a vertebrate novelty, we find that no single amphioxus tissue co-expresses all or most of these genes. However, most are variously co-expressed in mesodermal derivatives. Our results suggest that neural crest-derived cartilage evolved by serial cooption of genes which functioned primitively in mesoderm.

Usher syndrome type 1–associated cadherins shape the photoreceptor outer segment

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Parain, Karine; Aghaie, Asadollah; Picaud, Serge

2017-01-01

Usher syndrome type 1 (USH1) causes combined hearing and sight defects, but how mutations in USH1 genes lead to retinal dystrophy in patients remains elusive. The USH1 protein complex is associated with calyceal processes, which are microvilli of unknown function surrounding the base of the photoreceptor outer segment. We show that in Xenopus tropicalis, these processes are connected to the outer-segment membrane by links composed of protocadherin-15 (USH1F protein). Protocadherin-15 deficiency, obtained by a knockdown approach, leads to impaired photoreceptor function and abnormally shaped photoreceptor outer segments. Rod basal outer disks displayed excessive outgrowth, and cone outer segments were curved, with lamellae of heterogeneous sizes, defects also observed upon knockdown of Cdh23, encoding cadherin-23 (USH1D protein). The calyceal processes were virtually absent in cones and displayed markedly reduced F-actin content in rods, suggesting that protocadherin-15–containing links are essential for their development and/or maintenance. We propose that calyceal processes, together with their associated links, control the sizing of rod disks and cone lamellae throughout their daily renewal. PMID:28495838

Vertebral Fractures and Spondylosis in Men - Original Investigation

Directory of Open Access Journals (Sweden)

Selmin Gülbahar

2008-04-01

Full Text Available Aim: The aim of this study was to investigate the relationship between vertebral fractures and spondylosis and bone mineral density in men older than 60 years. Material and Method: Thirty-two men with back and low back pain aged over 60 years were included into the study. Thoracic and lumbar spine radiographs were taken and, anterior, central and posterior heights of each vertebral body from T4 to L5 was measured and than the number of vertebral fractures was assessed. Osteophyte and disc scores were used for evaluation of spondylosis. Bone mineral density was measured by dual-energy-X-ray absorptiometry. Measurements were obtained from lumbar vertebrae and proximal femoral region. Results: Significant positive correlations were found between vertebral fracture and osteophyte score and bone mineral density of total femoral region. When osteophyte score and total femoral bone mineral density were taken into consideration, there were no significant correlations between other parameters and vertebral fracture. Significant positive correlations were observed between osteophyte score and bone mineral density and t scores of L1-4. Also there were significant positive correlations between disc score and both bone mineral density and t scores of L1-4. Significant positive correlation was also found between femoral bone density and body weight. Conclusion: Finally, lumbar bone mineral density increases with spinal degenerative changes, but the increase in bone mineral density can not prevent sub clinic vertebral fractures. Especially, in the men who have intensive spinal degenerative changes, the measurement of lumbar bone mineral density is not enough for determining the fracture risk. Measurement of femoral bone mineral density and evaluation of clinic risk factors are more important for determining the fracture risk. (From the World of Osteoporosis 2008;14:1-6

Orientation-Selective Retinal Circuits in Vertebrates.

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Antinucci, Paride; Hindges, Robert

2018-01-01

Visual information is already processed in the retina before it is transmitted to higher visual centers in the brain. This includes the extraction of salient features from visual scenes, such as motion directionality or contrast, through neurons belonging to distinct neural circuits. Some retinal neurons are tuned to the orientation of elongated visual stimuli. Such 'orientation-selective' neurons are present in the retinae of most, if not all, vertebrate species analyzed to date, with species-specific differences in frequency and degree of tuning. In some cases, orientation-selective neurons have very stereotyped functional and morphological properties suggesting that they represent distinct cell types. In this review, we describe the retinal cell types underlying orientation selectivity found in various vertebrate species, and highlight their commonalities and differences. In addition, we discuss recent studies that revealed the cellular, synaptic and circuit mechanisms at the basis of retinal orientation selectivity. Finally, we outline the significance of these findings in shaping our current understanding of how this fundamental neural computation is implemented in the visual systems of vertebrates.

Proportional lumbar spine inter-vertebral motion patterns: a comparison of patients with chronic, non-specific low back pain and healthy controls.

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Mellor, Fiona E; Thomas, Peter W; Thompson, Paul; Breen, Alan C

2014-10-01

Identifying biomechanical subgroups in chronic, non-specific low back pain (CNSLBP) populations from inter-vertebral displacements has proven elusive. Quantitative fluoroscopy (QF) has excellent repeatability and provides continuous standardised inter-vertebral kinematic data from fluoroscopic sequences allowing assessment of mid-range motion. The aim of this study was to determine whether proportional continuous IV rotational patterns were different in patients and controls. A secondary aim was to update the repeatability of QF measurement of range of motion (RoM) for inter-vertebral (IV) rotation. Fluoroscopic sequences were recorded of passive, recumbent coronal and sagittal motion, which was controlled for range and velocity. Segments L2-5 in 40 primary care CNSLBP patients and 40 matched controls were compared. Patients also completed the von Korff Chronic Pain Grade and Roland and Morris Disability Questionnaire. Sequences were processed using automated image tracking algorithms to extract continuous inter-vertebral rotation data. These were converted to continuous proportional ranges of rotation (PR). The continuous proportional range variances were calculated for each direction and combined to produce a single variable representing their fluctuation (CPRV). Inter- and intra-rater repeatability were also calculated for the maximum IV-RoM measurements obtained during controlled trunk motion to provide an updated indication of the reliability and agreement of QF for measuring spine kinematics. CPRV was significantly higher in patients (0.011 vs. 0.008, Mann-Whitney two-sided p = 0.008), implying a mechanical subgroup. Receiver operating characteristic curve analysis found its sensitivity and specificity to be 0.78 % (60-90) and 0.55 % (37-73), respectively (area under the curve 0.672). CPRV was not correlated with pain severity or disability. The repeatability of maximum inter-vertebral range was excellent, but range was only significantly greater in patients

High prevalence of radiological vertebral fractures in HIV-infected males.

Science.gov (United States)

Torti, Carlo; Mazziotti, Gherardo; Soldini, Pier Antonio; Focà, Emanuele; Maroldi, Roberto; Gotti, Daria; Carosi, Giampiero; Giustina, Andrea

2012-06-01

Age-related co-morbidities including osteoporosis are relevant in patients responding to combination antiretroviral therapy (cART). Vertebral fractures are common osteoporotic fractures and their diagnosis is useful for managing at-risk individuals. However, there are few data from HIV-infected patients. Therefore, the aim of this study was to determine the prevalence of and factors associated with vertebral fractures in a population of HIV-infected males. A cross-sectional study of 160 HIV-infected patients with available chest X-rays was conducted from 1998 to 2010. One hundred and sixty-three males with comparable age and with no history of HIV infection were recruited as controls. Semi-quantitative evaluation of vertebral heights in lateral chest X-rays and quantitative morphometry assessment of centrally digitized images using dedicated morphometry software were utilized to detect prevalent vertebral fractures. The result showed that the vertebral fractures were detected in 43/160 (26.9%) HIV-infected patients and in 21/163 (12.9%) controls (P = 0.002). In HIV-infected patients with fractures, 27 had two or more fractures and ten patients had severe fractures. The prevalence of any fractures and multiple fractures in HIV-infected patients receiving cART (29.6 and 20.0%) was slightly higher than in HIV-infected patients not exposed to cART (17.1 and 5.7%), but significantly higher than control subjects (12.9 and 3.7%). At multivariable analyses, body mass index and diabetes mellitus were independently correlated with vertebral fractures in HIV-infected patients. We concluded that a significant proportion of HIV-infected males receiving cART showed vertebral fractures. Furthermore, proactive diagnosis of vertebral fragility fractures is particularly relevant in patients who are overweight or suffer from diabetes.

The pattern and prevalence of vertebral artery injury in patients with ...

African Journals Online (AJOL)

Other important risk factors for vertebral artery injury include facet joint dislocations and fractures of the first to the third cervical vertebral bodies. The aim of this study was to determine the pattern and prevalence of vertebral artery injury on CT angiography (CTA) in patients with cervical spine fractures. Method.

Recognizing and reporting vertebral fractures: reducing the risk of future osteoporotic fractures

International Nuclear Information System (INIS)

Lentle, B.C.; Brown, J.P.; Khan, A.

2007-01-01

Given the increasing evidence that vertebral fractures are underdiagnosed and not acted on, Osteoporosis Canada and the Canadian Association of Radiologists initiated a project to develop and publish a set of recommendations to promote and facilitate the diagnosis and reporting of vertebral fractures. The identification of spinal fractures is not uniform. More than 65% of vertebral fractures cause no symptoms. It is also apparent that vertebral fractures are inadequately recognized when the opportunity for diagnosis arises fortuitously. It is to patients' benefit that radiologists report vertebral fractures evident on a chest or other radiograph, no matter how incidental to the immediate clinical indication for the examination. The present recommendations can help to close the gap in care in recognizing and treating vertebral fractures, to prevent future fractures and thus reduce the burden of osteoporosis-related morbidity and mortality, as well as fracture-related costs to the health care system. Several studies indicate that a gap exists in regard to the diagnosis of vertebral fractures and the clinical response following such diagnosis. All recommendations presented here are based on consensus. These recommendations were developed by a multidisciplinary working group under the auspices of the Scientific Advisory Council of Osteoporosis Canada and the Canadian Association of Radiologists. Prevalent vertebral fractures have important clinical implications in terms of future fracture risk. Recognizing and reporting fractures incidental to radiologic examinations done for other reasons has the potential to reduce health care costs by initiating further steps in osteoporosis diagnosis and appropriate therapy. Physicians should be aware of the importance of vertebral fracture diagnosis in assessing future osteoporotic fracture risk. Vertebral fractures incidental to radiologic examinations done for other reasons should be identified and reported. Vertebral fractures

Visualization of the Origin of the Vertebral Arteries with Color Doppler Sonography

International Nuclear Information System (INIS)

Yoon, Seok Hwan; Lee, Won Hong; Lee, Dae Hyung

2009-01-01

Atherosclerotic disease at the origin of the vertebral arteries is one of the risk factors for vertebrobasilar ischemic disease. Assessment and visualization of the origin of the vertebral arteries with color doppler sonography is a non-trivial task. The aim of this study is to increase the visualization rate of the origin of the vertebral arteries with color doppler sonography. Color doppler sonography for the vertebral arteries included carotid arteries was performed to 198 patients. We first examined the vertebral artery in the upper neck in the direction of the subclavian artery to distinguish its origin more easily. If the vertebral artery origin was not visualized in natural position, the examiner pushed the transducer toward a clavicle or pushed the shoulder of patient by the other hand. The technical methods for visualization of the vertebral artery origin were classified into three grades: natural position, pushing the transducer, and pushing the shoulder of patient according to the depth (3.0 cm and shallower, deeper than 3.0 cm) of the origin. The origin of the vertebral arteries could be visualized in 97% on the right and in 92% on the left. The origin of the vertebral arteries could be visualized in 98.6%, 1.4%, and 0.0% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at shallower than 3.0 cm on the right side. The origin of the vertebral arteries could be visualized in 81.2%, 14.6%, and 4.2% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at deeper than 3.0 cm on the right side. The origin of the vertebral arteries could be visualized in 85.4%, 10.7%, and 3.9% in natural position, pushing the transducer, and pushing the shoulder of patient, respectively, at shallower than 3.0 cm on the left side. The origin of the vertebral arteries could be visualized in 55.7%, 30.4%, and 13.9% in natural position, pushing the transducer, and pushing the shoulder of

Percutaneous Vertebroplasty for Compression Fracture: Analysis of Vertebral Body Volume by CT Volumetry

International Nuclear Information System (INIS)

Komemushi, A.; Tanigawa, N.; Kariya, S.; Kojima, H.; Shomura, Y.; Sawada, S.

2005-01-01

Purpose: To evaluate the relationships between volume of vertebral bodies with compression fracture (measured by CT volumetry) before percutaneous vertebroplasty, the amount of bone cement injected, and the effect of treatment. Material and Methods: We examined 49 consecutive patients, with 104 vertebral body compression fractures, who underwent percutaneous injection of bone cement. Vertebral body volume was measured by CT volumetry. The patient's pain level was assessed using a visual analog scale (VAS) before and after the procedure. Improvement in VAS was defined as the decrease in VAS after the procedure. Relationships between vertebral body volume, the amount of bone cement, and the effect of treatment were evaluated using Pearson's correlation coefficient test. Results: Average vertebral body volume was 26.3 ±8.1 cm 3 ; average amount of bone cement was 3.2 ±1.1 ml; and average improvement in VAS was 4.9 ±2.7. The vertebral body volume was greater if a larger amount of bone cement was injected. There was a significant positive correlation between vertebral body volume and amount of bone cement ( r ∼ 0.44; P <0.0001). However, there was no correlation between vertebral body volume and improvement in VAS, or between amount of bone cement and improvement in VAS. Conclusion: In percutaneous vertebroplasty for vertebral body compression fracture, there is a positive correlation between vertebral body volume and amount of bone cement, but improvement in VAS does not correlate with vertebral body volume or amount of bone cement

Reconstruction techniques in the treatment of vertebral neoplasms.

Science.gov (United States)

Biagini, R; Boriani, S; Casadei, R; Bandiera, S; De Iure, F; Campanacci, L; Demitri, S; Orsini, U; Di Fiore, M

1997-01-01

The authors present a new system for the topographical description of vertebral neoplasms. The general criteria of reconstruction after curettage or vertebral resection are evaluated. The literature is reviewed in terms of the use of prostheses, bone grafts, cement and stabilization systems in the treatment of tumors of the spine. Indications for the different methods are discussed.

Measurement of vertebral bone density. Quantitative CT or dual-photon absorptiometry

International Nuclear Information System (INIS)

Bergot, C.; Laval-Jeantet, A.M.; Laval-Jeantet, M.H.; Kuntz, D.

1993-01-01

We have compared vertebral bone density measurements (QCT and DXA) in women in the postmenopausal period who underwent both examinations. Our aim was to study the results and to define the respective indications of QCT and DXA in various clinical pictures of osteoporosis. The subjects of the study were distributed into various groups according to the presence or absence of vertebral collapse and/or peripheral fractures. The results of the measurements were expressed as Z-scores (deviation from age-normal average) to suppress the age effect and to make comparison between both methods possible. The values of both measurements are significantly lower in case of vertebral involvement. QCT is more sensitive than DXA to discriminate vertebral collapse. A vertebral fragility threshold was defined at a Z-score of-1 with DXA and-1.25 with QCT, corresponding to the best sensitivity for an acceptable specificity. The results of densitometry suggest that there is a peripheral osteoporosis, different from vertebral osteoporosis, as early as the postmenopausal period. Since DXA is easy to implement, it can be used to screen osteoporosis. When the vertebral measurement with DXA is normal although osteoporosis is obvious (previous collapse or fracture), QCT must be used as it is more sensitive

Pediatric congenital vertebral artery arteriovenous malformation

International Nuclear Information System (INIS)

Shownkeen, Harish; Chenelle, Andrew G.; Origitano, Thomas C.; Bova, Davide

2003-01-01

Vertebral arteriovenous fistulas are rare in children and the congenital form has been seldom reported in the literature. Prior to using endovascular therapy techniques, only surgery was the main treatment. The most common endovascular treatment is through the use of detachable balloons. This report describes the clinical and radiological findings of a congenital vertebral artery fistula in a 20-month-old child. Balloons could not be safely employed; therefore, embolization was performed with Guglielmi detachable microcoils. We review the history and treatment of these lesions, their clinical presentation, and imaging features, including their outcome, with particular attention to the pediatric population. (orig.)

The pattern and prevalence of vertebral artery injury in patients with cervical spine fractures

Directory of Open Access Journals (Sweden)

Farzanah Ismail

2013-06-01

Method: A retrospective review of patients who had undergone CTA of the vertebral arteries was undertaken. Reports were reviewed to determine which patients met the inclusion criteria of having had both cervical spine fractures and CTA of the vertebral arteries. Images of patients who met the inclusion criteria were analysed by a radiologist. Results: The prevalence of vertebral artery injury was 33%. Four out of the 11 patients who had vertebral artery injury, had post-traumatic spasm of the artery, with associated thrombosis or occlusion of the vessel. In terms of blunt carotid vertebral injury (BCVI grading, most of the patients sustained grade IV injuries. Four patients who had vertebral artery injury had fractures of the upper cervical vertebrae, i.e. C1 to C3. Fifteen transverse process fractures were associated with vertebral artery injury. No vertebral artery injury was detected in patients who had facet joint subluxations. Conclusion: Patients with transverse process fractures of the cervical spine and upper cervical vertebral body fractures should undergo CTA to exclude vertebral artery injury.

Segmented block copolymers with monodisperse aramide end-segments

NARCIS (Netherlands)

Araichimani, A.; Gaymans, R.J.

2008-01-01

Segmented block copolymers were synthesized using monodisperse diaramide (TT) as hard segments and PTMO with a molecular weight of 2 900 g · mol-1 as soft segments. The aramide: PTMO segment ratio was increased from 1:1 to 2:1 thereby changing the structure from a high molecular weight multi-block

Cooperative Learning as a Tool To Teach Vertebrate Anatomy.

Science.gov (United States)

Koprowski, John L.; Perigo, Nan

2000-01-01

Describes a method for teaching biology that includes more investigative exercises that foster an environment for cooperative learning in introductory laboratories that focus on vertebrates. Fosters collaborative learning by facilitating interaction between students as they become experts on their representative vertebrate structures. (SAH)

High prevalence of morphometric vertebral deformities in patients with inflammatory bowel disease.

Science.gov (United States)

Heijckmann, Anna Caroline; Huijberts, Maya S P; Schoon, Erik J; Geusens, Piet; de Vries, Jolanda; Menheere, Paul P C A; van der Veer, Eveline; Wolffenbuttel, Bruce H R; Stockbrugger, Reinhold W; Dumitrescu, Bianca; Nieuwenhuijzen Kruseman, Arie C

2008-08-01

Earlier studies have documented that the prevalence of decreased bone mineral density (BMD) is elevated in patients with inflammatory bowel disease. The objective of this study was to investigate the prevalence of vertebral deformities in inflammatory bowel disease patients and their relation with BMD and bone turnover. One hundred and nine patients with Crohn's disease (CD) and 72 with ulcerative colitis (UC) (age 44.5+/-14.2 years) were studied. BMD of the hip (by dual X-ray absorptiometry) was measured and a lateral single energy densitometry of the spine for assessment of vertebral deformities was performed. Serum markers of bone resorption (carboxy-terminal cross-linked telopeptide of type I collagen) and formation (procollagen type I amino-terminal propeptide) were measured, and determinants of prevalent vertebral deformities were assessed using logistic regression analysis. Vertebral deformities were found in 25% of both CD and UC patients. Comparing patients with and without vertebral deformities, no significant difference was found between Z-scores and T-scores of BMD, or levels of serum carboxy-terminal cross-linked telopeptide of type I collagen and serum procollagen type I amino-terminal propeptide. Using logistic regression analysis the only determinant of any morphometric vertebral deformity was sex. The presence of multiple vertebral deformities was associated with older age and glucocorticoid use. The prevalence of morphometric vertebral deformities is high in CD and UC. Male sex, but neither disease activity, bone turnover markers, clinical risk factors, nor BMD predicted their presence. The determinants for having more than one vertebral deformity were age and glucocorticoid use. This implies that in addition to screening for low BMD, morphometric assessment of vertebral deformities is warranted in CD and UC.

Segmentation of consumer's markets and evaluation of market's segments

OpenAIRE

ŠVECOVÁ, Iveta

2013-01-01

The goal of this bachelor thesis was to explain a possibly segmentation of consumer´s markets for a chosen company, and to present a suitable goods offer, so it would be suitable to the needs of selected segments. The work is divided into theoretical and practical part. First part describes marketing, segmentation, segmentation of consumer's markets, consumer's market, market's segments a other terms. Second part describes an evaluation of questionnaire survey, discovering of market's segment...

Prevalent morphometric vertebral fractures in professional male rugby players.

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Karen Hind

Full Text Available There is an ongoing concern about the risk of injury to the spine in professional rugby players. The objective of this study was to investigate the prevalence of vertebral fracture using vertebral fracture assessment (VFA dual energy X-ray absorptiometry (DXA imaging in professional male rugby players. Ninety five professional rugby league (n = 52 and union (n = 43 players (n = 95; age 25.9 (SD 4.3 years; BMI: 29.5 (SD 2.9 kg.m2 participated in the research. Each participant received one VFA, and one total body and lumbar spine DXA scan (GE Lunar iDXA. One hundred and twenty vertebral fractures were identified in over half of the sample by VFA. Seventy four were graded mild (grade 1, 40 moderate (grade 2 and 6 severe (grade 3. Multiple vertebral fractures (≥2 were found in 37 players (39%. There were no differences in prevalence between codes, or between forwards and backs (both 1.2 v 1.4; p>0.05. The most common sites of fracture were T8 (n = 23, T9 (n = 18 and T10 (n = 21. The mean (SD lumbar spine bone mineral density Z-score was 2.7 (1.3 indicating high player bone mass in comparison with age- and sex-matched norms. We observed a high number of vertebral fractures using DXA VFA in professional rugby players of both codes. The incidence, aetiology and consequences of vertebral fractures in professional rugby players are unclear, and warrant timely, prospective investigation.

The Retrospective Analysis of Posterior Short-Segment Pedicle Instrumentation without Fusion for Thoracolumbar Burst Fracture with Neurological Deficit

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Zhouming Deng

2014-01-01

Full Text Available This study aims to investigate the efficacy of posterior short-segment pedicle instrumentation without fusion in curing thoracolumbar burst fracture. All of the 53 patients were treated with short-segment pedicle instrumentation and laminectomy without fusion, and the restoration of retropulsed bone fragments was conducted by a novel custom-designed repositor (RRBF. The mean operation time and blood loss during surgery were analyzed; the radiological index and neurological status were compared before and after the operation. The mean operation time was 93 min (range: 62–110 min and the mean intraoperative blood loss was 452 mL in all cases. The average canal encroachment was 50.04% and 10.92% prior to the surgery and at last followup, respectively (P<0.01. The preoperative kyphotic angle was 17.2 degree (±6.87 degrees, whereas it decreased to 8.42 degree (±4.99 degrees at last followup (P<0.01. Besides, the mean vertebral body height increased from 40.15% (±9.40% before surgery to 72.34% (±12.32% at last followup (P<0.01. 45 patients showed 1-2 grades improvement in Frankel’s scale at last followup. This technique allows for satisfactory canal clearance and restoration of vertebral body height and kyphotic angle, and it may promote the recovery of neurological function. However, further research is still necessary to confirm the efficacy of this treatment.

An Adaptable Spectrin/Ankyrin-Based Mechanism for Long-Range Organization of Plasma Membranes in Vertebrate Tissues.

Science.gov (United States)

Bennett, Vann; Lorenzo, Damaris N

2016-01-01

Ankyrins are membrane-associated proteins that together with their spectrin partners are responsible for micron-scale organization of vertebrate plasma membranes, including those of erythrocytes, excitable membranes of neurons and heart, lateral membrane domains of columnar epithelial cells, and striated muscle. Ankyrins coordinate functionally related membrane transporters and cell adhesion proteins (15 protein families identified so far) within plasma membrane compartments through independently evolved interactions of intrinsically disordered sequences with a highly conserved peptide-binding groove formed by the ANK repeat solenoid. Ankyrins are coupled to spectrins, which are elongated organelle-sized proteins that form mechanically resilient arrays through cross-linking by specialized actin filaments. In addition to protein interactions, cellular targeting and assembly of spectrin/ankyrin domains also critically depend on palmitoylation of ankyrin-G by aspartate-histidine-histidine-cysteine 5/8 palmitoyltransferases, as well as interaction of beta-2 spectrin with phosphoinositide lipids. These lipid-dependent spectrin/ankyrin domains are not static but are locally dynamic and determine membrane identity through opposing endocytosis of bulk lipids as well as specific proteins. A partnership between spectrin, ankyrin, and cell adhesion molecules first emerged in bilaterians over 500 million years ago. Ankyrin and spectrin may have been recruited to plasma membranes from more ancient roles in organelle transport. The basic bilaterian spectrin-ankyrin toolkit markedly expanded in vertebrates through gene duplications combined with variation in unstructured intramolecular regulatory sequences as well as independent evolution of ankyrin-binding activity by ion transporters involved in action potentials and calcium homeostasis. In addition, giant vertebrate ankyrins with specialized roles in axons acquired new coding sequences by exon shuffling. We speculate that

[Vertebral fractures in children with Type I Osteogenesis imperfecta].

Science.gov (United States)

Sepúlveda, Andrea M; Terrazas, Claudia V; Sáez, Josefina; Reyes, María L

2017-06-01

Osteogenesis imperfecta (OI) is an hereditary disease affecting conective tissue, mainly associated to growth retardation and pathological fractures. OI type I (OI type I), is the mildest, most often, and homogeneous in its fenotype. Vertebral fractures are the most significant complications, associated to skeletical and cardiopulmonary morbidity. To characterize clinically a cohort of children with OI type I. A cohort of OI type I children younger than 20 year old was evaluated. Demographic, clinical, biochemical and radiological data were registered. Sixty seven patients were included, 55% male, 69% resident in the Metropolitan Region. The mean age of diagnose was 2.9 years, 70% presented vertebral fractures on follow-up, mostly thoracic, and 50% before the age of 5 years. Fifty percentage presented vertebral fractures at diagnose, which was about the age of 5 years. Bone metabolic parameters were in the normal range, without significant change at the moment of vertebral fractures. Calcium intake was found to be below American Academy of Pediatrics recommendations at the time of the first fracture. In this study OI type I has an early diagnose, and vertebral fractures show a high incidence, mostly in toddlers. Calcium intake was found to be below reccomended values, and should be closely supervised in these patients.

Slipped vertebral epiphysis (report of 2 cases

Directory of Open Access Journals (Sweden)

Majid Reza Farrokhi

2009-02-01

Full Text Available

• Avulsion or fracture of posterior ring apophysis of lumbar vertebra is an uncommon cause of radicular low back pain in pediatric age group, adolescents and athletes. This lesion is one of differential diagnosis of disc herniation. We reported two teenage boys with sever low back pain and sciatica during soccer play that ultimately treated with diagnosis of lipped vertebral apophysis.
• KEY WORDS: Ring Apophysis, vertebral fracture, sciatica, low back pain, disc herniation.

Vertebral anomalies in children with Alagille syndrome: an analysis of 50 consecutive patients

International Nuclear Information System (INIS)

Sanderson, Evelyn; Newman, Vanessa; Haigh, Susan F.; Sidhu, Paul S.; Baker, Alastair

2002-01-01

Background: Vertebral anomalies may help differentiate Alagille syndrome from other causes of chronic cholestasis. We suspect significant under-reporting of vertebral anomalies in children with Alagille syndrome. Objective: To compare the vertebral anomalies in Alagille syndrome with those in patients with chronic cholestasis due to other causes. The accuracy of original radiographic reporting was evaluated. Materials and methods: Spinal radiographs of 50 patients with Alagille syndrome and 31 non-Alagille syndrome cholestatic patients were evaluated retrospectively by four trained radiologists. The number, site and type of vertebral anomaly were noted. The consensus evaluation was then compared to the original report. Results: Vertebral anomalies were found in 66% of patients with Alagille syndrome and 9.7% of cholestatic control subjects (P<0.0005). In the patients with Alagille syndrome, incomplete fusion of the anterior arch, most frequently at the D6-9 level, accounted for 123 of 126 anomalies. Multiple vertebral anomalies occurred in 48% of patients with Alagille syndrome (mean 2.5 anomalies). Vertebral anomalies were misreported in 54% of cases of Alagille syndrome. Conclusions: Vertebral anomalies are significantly more common in Alagille syndrome than in chronic cholestasis of other causes and are frequently overlooked. Reporting should be undertaken by a radiologist familiar with the appearance and location of these vertebral anomalies. (orig.)

Vertebrate Osmoregulation: A Student Laboratory Exercise Using Teleost Fish

Science.gov (United States)

Boily P.; Rees, B. B.; Williamson, L. A. C.

2007-01-01

Here, we describe a laboratory experiment as part of an upper-level vertebrate physiology course for biology majors to investigate the physiological response of vertebrates to osmoregulatory challenges. The experiment involves measuring plasma osmolality and Na[superscript +] -K[superscript +] -ATPase activity in gill tissue of teleost fish…

Algorithms for automatic segmentation of bovine embryos produced in vitro

International Nuclear Information System (INIS)

Melo, D H; Oliveira, D L; Nascimento, M Z; Neves, L A; Annes, K

2014-01-01

In vitro production has been employed in bovine embryos and quantification of lipids is fundamental to understand the metabolism of these embryos. This paper presents a unsupervised segmentation method for histological images of bovine embryos. In this method, the anisotropic filter was used in the differents RGB components. After pre-processing step, the thresholding technique based on maximum entropy was applied to separate lipid droplets in the histological slides in different stages: early cleavage, morula and blastocyst. In the postprocessing step, false positives are removed using the connected components technique that identify regions with excess of dye near pellucid zone. The proposed segmentation method was applied in 30 histological images of bovine embryos. Experiments were performed with the images and statistical measures of sensitivity, specificity and accuracy were calculated based on reference images (gold standard). The value of accuracy of the proposed method was 96% with standard deviation of 3%

Vertebral body trabecular density at the thoracolumbar junction using quantitative computed tomography

International Nuclear Information System (INIS)

Singer, K.P.; Breidahl, P.D.; Royal Perth Hospital

1990-01-01

Quantitative computed tomography was used to assess vertebral trabecular density in 26 post-mortem spines from individuals aged between 14 and 80 years. All vertebrae from T10 to L1 were scanned transversely near the mid-vertebral level with calculations of trabecular density in HUs averaged and referenced to a mineral equivalent phantom. An age-related decline in trabecular density was recorded (r=0.55, p<0.0001). Density measures from the anterior aspect of the vertebral body were significantly greater than from postero-lateral regions. From T10 to L1, there was a significant decrease in trabecular density, whereas density measures multiplied by vertebral body cross-sectional area were constant. Predictions of vertebral compressive strength using quantitative computed tomography may become more accurate by increasing the sampling area per scan and including vertebral body cross-sectional area as part of the radiologic assessment. (orig.)

Study regarding the incidence of physical deficiencies of the vertebral column at puberty

Directory of Open Access Journals (Sweden)

Livia Avramescu-Opriţoiu

2008-12-01

Full Text Available The physical deficiencies of the vertebral column at puberty have become an acute reality of our present time in the schools ofTimisoara and not only, reason for which a study regarding their incidence on the pupils at the age of puberty, from Timisoara,has been started; the study was performed on a 308 pupil group (V-XI classes and used as methods the somatoscopic andsomatometrical exam of the pupils, as well as a short period of time related to the daily activities, which could be the sublayerof these pathological changes at the level of the vertebral column. The results of the study confirmed the hypothesis inaccordance with which there is an increasing number of deficient postures and proper deficiencies at the level of the vertebralcolumn at the young people being studied, correlated with a daily program where the static activities (TV watching, computeruse, individual study, etc. prevail over the physical activities; in accordance with this study 20,13% of them pupils do notshow changes at the level of the axial segment, the rest of 79,87% being diagnosed with deficient postures (45,12%,respectively with proper deficiencies (34,75%; the type of the found deficiencies are scoliosis (14,94%, kiphoses (8,77%,lumbar hyperlordoses (6,82% and kiphoscolioses (2,27%. The alarming proportion of young people that have been diagnosedwith such modifications make us conclude that there is given an insignificant importance to the physical exercise, the mainmethod of primary prophylaxis, but secondary as well of these disturbances.

Prevalence of silent vertebral fractures detected by vertebral fracture assessment in young Portuguese men with hyperthyroidism.

Science.gov (United States)

Barbosa, Ana Paula; Rui Mascarenhas, Mário; Silva, Carlos Francisco; Távora, Isabel; Bicho, Manuel; do Carmo, Isabel; de Oliveira, António Gouveia

2015-02-01

Hyperthyroidism is a risk factor for reduced bone mineral density (BMD) and osteoporotic fractures. Vertebral fracture assessment (VFA) by dual-energy X-ray absorptiometry (DXA) is a radiological method of visualization of the spine, which enables patient comfort and reduced radiation exposure. This study was carried out to evaluate BMD and the prevalence of silent vertebral fractures in young men with hyperthyroidism. We conducted a cross-sectional study in a group of Portuguese men aged up to 50 years and matched in hyperthyroidism (n=24) and control (n=24) groups. A group of 48 Portuguese men aged up to 50 years was divided and matched in hyperthyroidism (n=24) and control (n=24) groups. BMD (g/cm(2)) at L1-L4, hip, radius 33%, and whole body as well as the total body masses (kg) were studied by DXA. VFA was used to detect fractures and those were classified by Genant's semiquantitative method. No patient had previously been treated for hyperthyroidism, osteoporosis, or low bone mass. Adequate statistical tests were used. The mean age, height, and total fat mass were similar in both groups (P≥0.05). The total lean body mass and the mean BMD at lumbar spine, hip, and whole body were significantly decreased in the hyperthyroidism group. In this group, there was also a trend for an increased prevalence of reduced BMD/osteoporosis and osteoporotic vertebral fractures. The results obtained using VFA technology (confirmed by X-ray) suggest that the BMD changes in young men with nontreated hyperthyroidism may lead to the development of osteoporosis and vertebral fractures. This supports the pertinence of using VFA in the routine of osteoporosis assessment to detect silent fractures precociously and consider early treatment. © 2015 European Society of Endocrinology.

Associations between the Cervical Vertebral Column and Craniofacial Morphology

DEFF Research Database (Denmark)

Sonnesen, Ane Liselotte

2010-01-01

Aim. To summarize recent studies on morphological deviations of the cervical vertebral column and associations with craniofacial morphology and head posture in nonsyndromic patients and in patients with obstructive sleep apnoea (OSA). Design. In these recent studies, visual assessment of the cerv......Aim. To summarize recent studies on morphological deviations of the cervical vertebral column and associations with craniofacial morphology and head posture in nonsyndromic patients and in patients with obstructive sleep apnoea (OSA). Design. In these recent studies, visual assessment...... of the cervical vertebral column and cephalometric analysis of the craniofacial skeleton were performed on profile radiographs of subjects with neutral occlusion, patients with severe skeletal malocclusions and patients with OSA. Material from human triploid foetuses and mouse embryos was analysed histologically....... Results. Recent studies have documented associations between fusion of the cervical vertebral column and craniofacial morphology, including head posture in patients with severe skeletal malocclusions. Histological studies on prenatal material supported these findings. Conclusion. It is suggested...

Correlation between dental maturity and cervical vertebral maturity.

Science.gov (United States)

Chen, Jianwei; Hu, Haikun; Guo, Jing; Liu, Zeping; Liu, Renkai; Li, Fan; Zou, Shujuan

2010-12-01

The aim of this study was to investigate the association between dental and skeletal maturity. Digital panoramic radiographs and lateral skull cephalograms of 302 patients (134 boys and 168 girls, ranging from 8 to 16 years of age) were examined. Dental maturity was assessed by calcification stages of the mandibular canines, first and second premolars, and second molars, whereas skeletal maturity was estimated by the cervical vertebral maturation (CVM) stages. The Spearman rank-order correlation coefficient was used to measure the association between CVM stage and dental calcification stage of individual teeth. The mean chronologic age of girls was significantly lower than that of boys in each CVM stage. The Spearman rank-order correlation coefficients between dental maturity and cervical vertebral maturity ranged from 0.391 to 0.582 for girls and from 0.464 to 0.496 for boys (P cervical vertebral maturation stage. The development of the mandibular second molar in females and that of the mandibular canine in males had the strongest correlations with cervical vertebral maturity. Therefore, it is practical to consider the relationship between dental and skeletal maturity when planning orthodontic treatment. Copyright © 2010 Mosby, Inc. All rights reserved.

Vertebral Artery Dissection Causing Stroke After Trampoline Use.

Science.gov (United States)

Casserly, Courtney S; Lim, Rodrick K; Prasad, Asuri Narayan

2015-11-01

The aim of this study was to report a case of a 4-year-old boy who had been playing on the trampoline and presented to the emergency department (ED) with vomiting and ataxia, and had a vertebral artery dissection with subsequent posterior circulation infarcts. This study is a chart review. The patient presented to the emergency department with a 4-day history of vomiting and gait unsteadiness. A computed tomography scan of his head revealed multiple left cerebellar infarcts. Subsequent magnetic resonance imaging/magnetic resonance angiogram of his head and neck demonstrated multiple infarcts involving the left cerebellum, bilateral thalami, and left occipital lobe. A computed tomography angiogram confirmed the presence of a left vertebral artery dissection. Vertebral artery dissection is a relatively common cause of stroke in the pediatric age group. Trampoline use has been associated with significant risk of injury to the head and neck. Patients who are small and/or young are most at risk. In this case, minor trauma secondary to trampoline use could be a possible mechanism for vertebral artery dissection and subsequent strokes. The association in this case warrants careful consideration because trampoline use could pose a significant risk to pediatric users.

Comparative Studies of Vertebrate Platelet Glycoprotein 4 (CD36

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Roger S. Holmes

2012-09-01

Full Text Available Platelet glycoprotein 4 (CD36 (or fatty acyl translocase [FAT], or scavenger receptor class B, member 3 [SCARB3] is an essential cell surface and skeletal muscle outer mitochondrial membrane glycoprotein involved in multiple functions in the body. CD36 serves as a ligand receptor of thrombospondin, long chain fatty acids, oxidized low density lipoproteins (LDLs and malaria-infected erythrocytes. CD36 also influences various diseases, including angiogenesis, thrombosis, atherosclerosis, malaria, diabetes, steatosis, dementia and obesity. Genetic deficiency of this protein results in significant changes in fatty acid and oxidized lipid uptake. Comparative CD36 amino acid sequences and structures and CD36 gene locations were examined using data from several vertebrate genome projects. Vertebrate CD36 sequences shared 53–100% identity as compared with 29–32% sequence identities with other CD36-like superfamily members, SCARB1 and SCARB2. At least eight vertebrate CD36 N-glycosylation sites were conserved which are required for membrane integration. Sequence alignments, key amino acid residues and predicted secondary structures were also studied. Three CD36 domains were identified including cytoplasmic, transmembrane and exoplasmic sequences. Conserved sequences included N- and C-terminal transmembrane glycines; and exoplasmic cysteine disulphide residues; TSP-1 and PE binding sites, Thr92 and His242, respectively; 17 conserved proline and 14 glycine residues, which may participate in forming CD36 ‘short loops’; and basic amino acid residues, and may contribute to fatty acid and thrombospondin binding. Vertebrate CD36 genes usually contained 12 coding exons. The human CD36 gene contained transcription factor binding sites (including PPARG and PPARA contributing to a high gene expression level (6.6 times average. Phylogenetic analyses examined the relationships and potential evolutionary origins of the vertebrate CD36 gene with vertebrate

Epidemiologia do traumatismo da coluna vertebral

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Marcelo Ferraz de Campos

Full Text Available OBJETIVO: Avaliação epidemiológica retrospectiva de 100 casos de traumatismo da coluna vertebral. MÉTODO: Estudo transversal de dados colhidos por levantamento de prontuário, segundo protocolo de decodificação local. RESULTADOS: Predomínio etário de 20 a 40 anos em 64% dos casos; sexo masculino em 86%; segmento toracolombar mais comumente atingido 64% e 36% para o segmento cervical; principais causas foram às quedas em 40%, seguidas de acidentes automobilísticos em 25% e quedas da laje 23%. A prevalência dos ferimentos por arma de fogo foi de 7%, mergulho em águas rasas 3% e agressões 2%. Houve análise complementar com cruzamentos entre idade, sexo, causa e segmento da coluna vertebral acometido, observando que o segmento cervical teve grande predomínio nas mulheres em relação aos homens em 85,7% X 14,3%. CONCLUSÃO: O traumatismo da coluna vertebral ocorreu predominantemente em homens entre 20 e 40 anos e o segmento cervical foi o mais acometido nas mulheres em relação aos homens na proporção de 6:1.

CT diagnosis in the evaluation of vertebral trauma

International Nuclear Information System (INIS)

Emori, Takumi; Kadoya, Satoru; Nakamura, Tsutomu; Ito, Shotaro; Kwak, Ryungchan

1984-01-01

The diagnostic capability of the CT scan of the vertebral trauma and a comparison with the results of a routine roentgenogram and tomogram were studied in 11 patients. In total, there were 15 fractured vertebrae: 3 in the upper cervical, 3 in the lower cervical, and 9 in the thoracic and thoraco-lumbar vertebrae. In the detailed evaluation of the vertebral fractures, CT provided more information than plain films in all 15 fractured vertebrae, with a better visualization of the spinal bony details, particularly at the upper cervical, thoracic, and thoraco-lumbar levels, where the interpretation of the spinal abnormalities is usually difficult because of adjacent structures such as the skull and thorax. Only CT was able to demonstrate impingements on the vertebral canal by bony fragments. Post-traumatic syringomyelia was incidentally demonstrated in one patient on a plain CT. In 6 patients, conventional tomography was done, but no additional information with regard to spinal instability and spinal-cord compression was obtained. The usage of sagittal tomography was also limited, because it required a change in the patient's position, which might worsen the neurological deficits. On the other hand, a plain roentgenogram and conventional tomography were superior in the evaluation of spinal malalignment and fractures running horizontally. In summary, both plain roentgenograms and CT images provided detailed information about vertebral injury, whereas conventional tomography is judged to be inferior and not always necessary. Based on these results, our new diagnostic and therapeutic approaches using CT for the vertebral injuries were presented. (author)

Birth and death of gene overlaps in vertebrates

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Makałowska Izabela

2007-10-01

Full Text Available Abstract Background Between five and fourteen per cent of genes in the vertebrate genomes do overlap sharing some intronic and/or exonic sequence. It was observed that majority of these overlaps are not conserved among vertebrate lineages. Although several mechanisms have been proposed to explain gene overlap origination the evolutionary basis of these phenomenon are still not well understood. Here, we present results of the comparative analysis of several vertebrate genomes. The purpose of this study was to examine overlapping genes in the context of their evolution and mechanisms leading to their origin. Results Based on the presence and arrangement of human overlapping genes orthologs in rodent and fish genomes we developed 15 theoretical scenarios of overlapping genes evolution. Analysis of these theoretical scenarios and close examination of genomic sequences revealed new mechanisms leading to the overlaps evolution and confirmed that many of the vertebrate gene overlaps are not conserved. This study also demonstrates that repetitive elements contribute to the overlapping genes origination and, for the first time, that evolutionary events could lead to the loss of an ancient overlap. Conclusion Birth as well as most probably death of gene overlaps occurred over the entire time of vertebrate evolution and there wasn't any rapid origin or 'big bang' in the course of overlapping genes evolution. The major forces in the gene overlaps origination are transposition and exaptation. Our results also imply that origin of overlapping genes is not an issue of saving space and contracting genomes size.

Tracing the evolutionary origin of vertebrate skeletal tissues: insights from cephalochordate amphioxus.

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Yong, Luok Wen; Yu, Jr-Kai

2016-08-01

Vertebrate mineralized skeletal tissues are widely considered as an evolutionary novelty. Despite the importance of these tissues to the adaptation and radiation of vertebrate animals, the evolutionary origin of vertebrate skeletal tissues remains largely unclear. Cephalochordates (Amphioxus) occupy a key phylogenetic position and can serve as a valuable model for studying the evolution of vertebrate skeletal tissues. Here we summarize recent advances in amphioxus developmental biology and comparative genomics that can help to elucidate the evolutionary origins of the vertebrate skeletal tissues and their underlying developmental gene regulatory networks (GRN). By making comparisons to the developmental studies in vertebrate models and recent discoveries in paleontology and genomics, it becomes evident that the collagen matrix-based connective tissues secreted by the somite-derived cells in amphioxus likely represent the rudimentary skeletal tissues in chordates. We propose that upon the foundation of this collagenous precursor, novel tissue mineralization genes that arose from gene duplications were incorporated into an ancestral mesodermal GRN that makes connective and supporting tissues, leading to the emergence of highly-mineralized skeletal tissues in early vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lampreys, the jawless vertebrates, contain only two ParaHox gene clusters.

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Zhang, Huixian; Ravi, Vydianathan; Tay, Boon-Hui; Tohari, Sumanty; Pillai, Nisha E; Prasad, Aravind; Lin, Qiang; Brenner, Sydney; Venkatesh, Byrappa

2017-08-22

ParaHox genes ( Gsx , Pdx , and Cdx ) are an ancient family of developmental genes closely related to the Hox genes. They play critical roles in the patterning of brain and gut. The basal chordate, amphioxus, contains a single ParaHox cluster comprising one member of each family, whereas nonteleost jawed vertebrates contain four ParaHox genomic loci with six or seven ParaHox genes. Teleosts, which have experienced an additional whole-genome duplication, contain six ParaHox genomic loci with six ParaHox genes. Jawless vertebrates, represented by lampreys and hagfish, are the most ancient group of vertebrates and are crucial for understanding the origin and evolution of vertebrate gene families. We have previously shown that lampreys contain six Hox gene loci. Here we report that lampreys contain only two ParaHox gene clusters (designated as α- and β-clusters) bearing five ParaHox genes ( Gsxα , Pdxα , Cdxα , Gsxβ , and Cdxβ ). The order and orientation of the three genes in the α-cluster are identical to that of the single cluster in amphioxus. However, the orientation of Gsxβ in the β-cluster is inverted. Interestingly, Gsxβ is expressed in the eye, unlike its homologs in jawed vertebrates, which are expressed mainly in the brain. The lamprey Pdxα is expressed in the pancreas similar to jawed vertebrate Pdx genes, indicating that the pancreatic expression of Pdx was acquired before the divergence of jawless and jawed vertebrate lineages. It is likely that the lamprey Pdxα plays a crucial role in pancreas specification and insulin production similar to the Pdx of jawed vertebrates.

Vertebral bone mineral measurement using dual photon absorptiometry and computed tomography

International Nuclear Information System (INIS)

Eriksson, S.; Isberg, B.; Lindgren, U.; Huddinge Univ. Hospital

1988-01-01

The lumbar spine of 14 cadavers was studied both by 153 Gd dual photon absorptiometry (DPA) and quantitative computed tomography (QCT) at 96 and 125 kVp. The intact spine and the individual vertebrae were analyzed. After these measurements the ash content of the vertebral body, the posterior elements, and the transverse processes was determined. The fat content of the vertebral body as well as its volume was also measured. With DPA, the bone mineral content (BMC) determined in situ as well as on excised spine specimens correlated highly with the amount of total vertebral ash (r > 0.92, SEE 0.81, SEE 3 ). The so-called corpus density and central density determinations were less accurate. No difference in accuracy was found between measurements when using 3 mm and 4.5 mm step intervals. Variations in the distribution of mineral between the vertebral body and the posterior elements contribute to the error in predicting vertebral body mineral with DPA. QCT gave a smaller error when a cylindric portion of the vertebral body with a 20 diameter was measured compared with one with a 9 mm diameter, when the dual energy technique was used (p 3 ). Single energy QCT was insignificantly less accurate than dual energy QCT. Only small differences were found between vertebrae with high fat density of the vertebral body when single or dual QCT was used. QCT was more accurate than DPA in the prediction of the mineral density of individual vertebral bodies (p < 0.05) but no difference was found when the average values for the lumbar spine were calculated. (orig.)

Origin and evolution of retinoid isomerization machinery in vertebrate visual cycle: hint from jawless vertebrates.

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Poliakov, Eugenia; Gubin, Alexander N; Stearn, Olivia; Li, Yan; Campos, Maria Mercedes; Gentleman, Susan; Rogozin, Igor B; Redmond, T Michael

2012-01-01

In order to maintain visual sensitivity at all light levels, the vertebrate eye possesses a mechanism to regenerate the visual pigment chromophore 11-cis retinal in the dark enzymatically, unlike in all other taxa, which rely on photoisomerization. This mechanism is termed the visual cycle and is localized to the retinal pigment epithelium (RPE), a support layer of the neural retina. Speculation has long revolved around whether more primitive chordates, such as tunicates and cephalochordates, anticipated this feature. The two key enzymes of the visual cycle are RPE65, the visual cycle all-trans retinyl ester isomerohydrolase, and lecithin:retinol acyltransferase (LRAT), which generates RPE65's substrate. We hypothesized that the origin of the vertebrate visual cycle is directly connected to an ancestral carotenoid oxygenase acquiring a new retinyl ester isomerohydrolase function. Our phylogenetic analyses of the RPE65/BCMO and N1pC/P60 (LRAT) superfamilies show that neither RPE65 nor LRAT orthologs occur in tunicates (Ciona) or cephalochordates (Branchiostoma), but occur in Petromyzon marinus (Sea Lamprey), a jawless vertebrate. The closest homologs to RPE65 in Ciona and Branchiostoma lacked predicted functionally diverged residues found in all authentic RPE65s, but lamprey RPE65 contained all of them. We cloned RPE65 and LRATb cDNAs from lamprey RPE and demonstrated appropriate enzymatic activities. We show that Ciona ß-carotene monooxygenase a (BCMOa) (previously annotated as an RPE65) has carotenoid oxygenase cleavage activity but not RPE65 activity. We verified the presence of RPE65 in lamprey RPE by immunofluorescence microscopy, immunoblot and mass spectrometry. On the basis of these data we conclude that the crucial transition from the typical carotenoid double bond cleavage functionality (BCMO) to the isomerohydrolase functionality (RPE65), coupled with the origin of LRAT, occurred subsequent to divergence of the more primitive chordates (tunicates, etc

Segmentation of dermatoscopic images by frequency domain filtering and k-means clustering algorithms.

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Rajab, Maher I

2011-11-01

Since the introduction of epiluminescence microscopy (ELM), image analysis tools have been extended to the field of dermatology, in an attempt to algorithmically reproduce clinical evaluation. Accurate image segmentation of skin lesions is one of the key steps for useful, early and non-invasive diagnosis of coetaneous melanomas. This paper proposes two image segmentation algorithms based on frequency domain processing and k-means clustering/fuzzy k-means clustering. The two methods are capable of segmenting and extracting the true border that reveals the global structure irregularity (indentations and protrusions), which may suggest excessive cell growth or regression of a melanoma. As a pre-processing step, Fourier low-pass filtering is applied to reduce the surrounding noise in a skin lesion image. A quantitative comparison of the techniques is enabled by the use of synthetic skin lesion images that model lesions covered with hair to which Gaussian noise is added. The proposed techniques are also compared with an established optimal-based thresholding skin-segmentation method. It is demonstrated that for lesions with a range of different border irregularity properties, the k-means clustering and fuzzy k-means clustering segmentation methods provide the best performance over a range of signal to noise ratios. The proposed segmentation techniques are also demonstrated to have similar performance when tested on real skin lesions representing high-resolution ELM images. This study suggests that the segmentation results obtained using a combination of low-pass frequency filtering and k-means or fuzzy k-means clustering are superior to the result that would be obtained by using k-means or fuzzy k-means clustering segmentation methods alone. © 2011 John Wiley & Sons A/S.

Vertebral column aggressive osteoblastoma: two cases report and literature review

International Nuclear Information System (INIS)

Sabedotti, Ismail Fernando; Sabedotti, Valdir

2007-01-01

Osteoblastoma is a bone neoplasy that in most circumstances present a low aggressive aspect on radiographic studies, but in some cases may acquire an aggressive pattern, rupturing the bone cortex and invading nearby structures. Most cases occur on the vertebral column, especially at the posterior arch and occasionally involving the vertebral body. Differential diagnosis of the aggressive form is made with osteosarcomas. This review reports two cases of osteoblastomas involving vertebral column, with an aggressive pattern on radiologic studies, and their histologic confirmation. (author)

Evolution of the shut-off steps of vertebrate phototransduction

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Patel, Hardip R.; Chuah, Aaron

2018-01-01

Different isoforms of the genes involved in phototransduction are expressed in vertebrate rod and cone photoreceptors, providing a unique example of parallel evolution via gene duplication. In this study, we determine the molecular phylogeny of the proteins underlying the shut-off steps of phototransduction in the agnathan and jawed vertebrate lineages. For the G-protein receptor kinases (GRKs), the GRK1 and GRK7 divisions arose prior to the divergence of tunicates, with further expansion during the two rounds of whole-genome duplication (2R); subsequently, jawed and agnathan vertebrates retained different subsets of three isoforms of GRK. For the arrestins, gene expansion occurred during 2R. Importantly, both for GRKs and arrestins, the respective rod isoforms did not emerge until the second round of 2R, just prior to the separation of jawed and agnathan vertebrates. For the triplet of proteins mediating shut-off of the G-protein transducin, RGS9 diverged from RGS11, probably at the second round of 2R, whereas Gβ5 and R9AP appear not to have undergone 2R expansion. Overall, our analysis provides a description of the duplications and losses of phototransduction shut-off genes that occurred during the transition from a chordate with only cone-like photoreceptors to an ancestral vertebrate with both cone- and rod-like photoreceptors. PMID:29321241

Analysis of the vertebral venous system in relation to cerebral venous drainage on MR angiography

International Nuclear Information System (INIS)

Baik, Seung Kug; Sohn, Chul Ho; Kim, Gab Chul; Kim, Yong Sun

2004-01-01

In the supine position, cerebral venous drainage occurs primarily through the internal jugular veins, as seen on venous phase cerebral angiography. However, in the erect position, the vertebral venous system represents the major alternative pathway of cerebral venous drainage, while outflow through the internal jugular veins is absent or negligible. The purpose of this study is to evaluate the vertebral venous system and its relationship between the surrounding venous structures using magnetic resonance angiography (MRA) in the case of subjects in the supine position. We retrospectively reviewed the results of 65 patients (M:F = 31: 34, mean age 61.6 years) who underwent multi-phase contrast-enhanced carotid MRA. The imaging studies were performed using a 3.0 T MR unit (TR: 5.2, TE: 1.1, FA: 20, 3.8 thickness, EC: 1). We analyzed the appearance and extent of the vertebral venous system (vertebral venous plexus and vertebral artery venous plexus) and the internal jugular vein on the venous phase images. We also evaluated the main drainage pattern of the cerebral venous drainage and the drainage pattern of the vertebral venous system. The visualized vertebral venous system was defined as either poor, vertebral venous plexus dominant, vertebral artery venous plexus dominant or mixed. In the vertebral venous system, the vertebral artery venous plexus was visualized in 54 cases (83%). The appearance of the visualized vertebral artery venous plexus was symmetrical in 39 cases (72%) and asymmetrical in 15 cases (28%). The extent of the visualized vertebral artery venous plexus was partial in 26 cases (48%) and complete in 28 cases (52%). The vertebral venous plexus was visualized in 62 cases (95%). The appearance of the visualized vertebral artery venous plexus was symmetrical in 43 cases (69%) and asymmetrical in 19 cases (31%). The extent of the visualized vertebral artery venous plexus was partial in 35 cases (56%) and complete in 27 cases (44%). The appearance of the

Maxillary Anterior Segmental Distraction Osteogenesis to Correct Maxillary Deficiencies in a Patient With Cleft Lip and Palate.

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Kageyama-Iwata, Asuka; Haraguchi, Seiji; Iida, Seiji; Aikawa, Tomonao; Yamashiro, Takashi

2017-07-01

This report describes a case of successful orthodontic treatment using maxillary anterior segmental distraction osteogenesis with an internal maxillary distractor and bilateral sagittal split ramus osteotomy in a girl with cleft lip and palate. A 16-year-old girl with unilateral cleft lip and palate exhibited midface retrusion because of growth inhibition of the maxillary complex and mandibular excess. After the presurgical orthodontic treatment, 6.0-mm advancement of the maxillary anterior segment and 4.0-mm set back of the mandible were performed. After a retention period, the patient's midface convexity was greatly improved and the velopharyngeal competence was preserved without relapse.

Predictors of excessive use of social media and excessive online gaming in Czech teenagers.

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Spilková, Jana; Chomynová, Pavla; Csémy, Ladislav

2017-12-01

Background and aims Young people's involvement in online gaming and the use of social media are increasing rapidly, resulting in a high number of excessive Internet users in recent years. The objective of this paper is to analyze the situation of excessive Internet use among adolescents in the Czech Republic and to reveal determinants of excessive use of social media and excessive online gaming. Methods Data from secondary school students (N = 4,887) were collected within the 2015 European School Survey Project on Alcohol and Other Drugs. Logistic regression models were constructed to describe the individual and familial discriminative factors and the impact of the health risk behavior of (a) excessive users of social media and (b) excessive players of online games. Results The models confirmed important gender-specific distinctions - while girls are more prone to online communication and social media use, online gaming is far more prevalent among boys. The analysis did not indicate an influence of family composition on both the excessive use of social media and on excessive online gaming, and only marginal effects for the type of school attended. We found a connection between the excessive use of social media and binge drinking and an inverse relation between excessive online gaming and daily smoking. Discussion and conclusion The non-existence of significant associations between family environment and excessive Internet use confirmed the general, widespread of this phenomenon across the social and economic strata of the teenage population, indicating a need for further studies on the topic.

Stature estimation based on vertebral morphometry by dual energy X-rays absorptiometry imaging in Italian females

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Chantal Milani

2017-02-01

Full Text Available Anthropological profile in forensic context includes the assessment of parameters as ancestry, sex, age and stature of an individual by the analysis of skeletal remains. Stature can be estimated from decomposed and fully or partially skeletonized remains by means of anatomical or mathematical methods applied on the whole skeleton or single bones. Many authors calculated regression formulae for the living stature estimation by these methods, in particular based on a population similar to the remains recovered. Long bones are commonly used for stature estimation, but, when they are missing, methods involving different parts of the skeleton are needed. In this preliminary study we measured heights of the vertebral bodies in a female Caucasian Italian population, evaluated by images of morphometric X-ray absorptiometry based on dual-energy X-ray absorptiometry in living subjects investigated for routine diagnostic purposes. Thoracic and lumbar segments of the spine were measured and statistical analysis was performed, thus obtaining regression formulae for estimated living stature from thoraco-lumbar spine segments (T6-T12, L1-L4 and T6-L4. We propose this method for stature evaluation in physical or forensic anthropology when the spine is available and long bones are missing.

ORIGINAL ARTICLE The pattern and prevalence of vertebral artery ...

African Journals Online (AJOL)

vertebral artery injury in all patients who have fractures involving the transverse foraminae of the cervical spine, those with facet joint dislocations, and those with fractures involving the first to the third cervical vertebrae. The aim of this study was to determine the pattern and prevalence of vertebral artery injury using CTA in ...

Vertebral fractures in patients with rheumatoid arthritis treated with corticosteroids

NARCIS (Netherlands)

Lems, W. F.; Jahangier, Z. N.; Jacobs, J. W.; Bijlsma, J. W.

1995-01-01

To examine the relationship between roentgenological deformities of the vertebral column and clinical manifestations of vertebral fractures in patients with RA, treated with glucocorticosteroids (Cs). In all outpatients of Utrecht University Hospital with RA, who were currently using Cs (n = 52),

Methods to score vertebral deformities in patients with rheumatoid arthritis

NARCIS (Netherlands)

Lems, W. F.; Jahangier, Z. N.; Raymakers, J. A.; Jacobs, J. W.; Bijlsma, J. W.

1997-01-01

The objective was to compare four different scoring methods for vertebral deformities: the semiquantitative Kleerekoper score and three quantitative scores (according to Minne, Melton and Raymakers) in patients with rheumatoid arthritis (RA). Lateral radiographs of the thoracic and lumbar vertebral

Evolutionary Transition of Promoter and Gene Body DNA Methylation across Invertebrate-Vertebrate Boundary.

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Keller, Thomas E; Han, Priscilla; Yi, Soojin V

2016-04-01

Genomes of invertebrates and vertebrates exhibit highly divergent patterns of DNA methylation. Invertebrate genomes tend to be sparsely methylated, and DNA methylation is mostly targeted to a subset of transcription units (gene bodies). In a drastic contrast, vertebrate genomes are generally globally and heavily methylated, punctuated by the limited local hypo-methylation of putative regulatory regions such as promoters. These genomic differences also translate into functional differences in DNA methylation and gene regulation. Although promoter DNA methylation is an important regulatory component of vertebrate gene expression, its role in invertebrate gene regulation has been little explored. Instead, gene body DNA methylation is associated with expression of invertebrate genes. However, the evolutionary steps leading to the differentiation of invertebrate and vertebrate genomic DNA methylation remain unresolved. Here we analyzed experimentally determined DNA methylation maps of several species across the invertebrate-vertebrate boundary, to elucidate how vertebrate gene methylation has evolved. We show that, in contrast to the prevailing idea, a substantial number of promoters in an invertebrate basal chordate Ciona intestinalis are methylated. Moreover, gene expression data indicate significant, epigenomic context-dependent associations between promoter methylation and expression in C. intestinalis. However, there is no evidence that promoter methylation in invertebrate chordate has been evolutionarily maintained across the invertebrate-vertebrate boundary. Rather, body-methylated invertebrate genes preferentially obtain hypo-methylated promoters among vertebrates. Conversely, promoter methylation is preferentially found in lineage- and tissue-specific vertebrate genes. These results provide important insights into the evolutionary origin of epigenetic regulation of vertebrate gene expression. © The Author(s) 2015. Published by Oxford University Press on behalf

Underdiagnosis of Vertebral Collapse on Routine Multidetector Computed Tomography Scan of the Abdomen

International Nuclear Information System (INIS)

Obaid, H.; Husamaldin, Z.; Bhatt, R.

2008-01-01

Background: Vertebral fractures are commonly associated with osteoporosis and have significant morbidity and mortality rates. Osteoporotic vertebral fractures are presently considered as a treatable and preventable condition, and early detection is vital for further management. The evaluation of vertebral compression on multidetector computed tomography (MDCT) scans of the abdomen has, to our knowledge, not been reported before. Purpose: To assess the prevalence of vertebral collapse on routine abdominal CT scans, and to evaluate the usefulness of the multiplanar reconstruction (MPR) capability of MDCT scans in accurately identifying vertebral abnormalities such as vertebral collapse, spondylolisthesis, and retrolisthesis. Material and Methods: A retrospective review of 307 MDCT scans of the abdomen was carried out at a university teaching hospital. Identifiable patient information was anonymized for data protection. All images were reviewed on a picture archiving and communications system (PACS) using sagittal MPR and bone window for the assessment of the vertebrae. Data were collected from the Computerized Radiology Information System (CRIS). Results: Vertebral collapse was seen in 42 (13.6%) of the 307 patients undergoing routine MDCT of the abdomen. Multilevel and single-level collapses were seen in 24 and 18 patients, respectively. Spondylolisthesis was identified in 5.5% (n=17), and retrolisthesis was seen in 0.6% (n=2). All patients with vertebral fracture were older than 50 years. Women were more commonly affected than men. Conclusion: A significant number of patients with vertebral collapse were diagnosed using MPR on MDCT routine scans of the abdomen

Reference values for radiological evaluation of cervical vertebral body shape and spinal canal

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Remes, V.M. [Hospital for Children and Adolescents, Helsinki University Central Hospital (Finland); Heinaenen, M.T.; Marttinen, E.J. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Kinnunen, J.S. [Department of Radiology, Helsinki University Central Hospital, HYKS (Finland)

2000-03-01

Background. Defining normal values is essential for reliable evaluation of growth disturbances. Previous studies of the cervical spine have mainly focused on the sagittal canal diameter and interpedicular distances. Values for vertebral body height and depth have been published only in adult men and cadavers.Objectives. To define normal values for vertebral body height (H)/vertebral body depth (D) ratio (H/D ratio) and sagittal canal diameter (S)/vertebral body depth ratio (S/D ratio) in C2-7.Materials and methods. Lateral cervical spine radiographs were available from 441 children and 192 adults. Subjects' ages varied from newborn to 39 years. Vertebral body height and depth and sagittal canal diameter were measured and ratios were calculated. This was a cross-sectional and retrospective study.Results. Vertebral bodies grow relatively more in height than in depth, most actively at puberty. At all levels, the H/D ratio remains below 1, indicating that vertebral body depth is greater than height. The SD ratio is quite stable until 7-8 years of age and then it starts to decline slowly.Conclusions. When estimating platyspondyly, the age of the patient must be taken into consideration because vertebral body height is lower in children. Growth of the spinal canal declines after 7-8 years of age. (orig.)

Reference values for radiological evaluation of cervical vertebral body shape and spinal canal

International Nuclear Information System (INIS)

Remes, V.M.; Heinaenen, M.T.; Marttinen, E.J.; Kinnunen, J.S.

2000-01-01

Background. Defining normal values is essential for reliable evaluation of growth disturbances. Previous studies of the cervical spine have mainly focused on the sagittal canal diameter and interpedicular distances. Values for vertebral body height and depth have been published only in adult men and cadavers.Objectives. To define normal values for vertebral body height (H)/vertebral body depth (D) ratio (H/D ratio) and sagittal canal diameter (S)/vertebral body depth ratio (S/D ratio) in C2-7.Materials and methods. Lateral cervical spine radiographs were available from 441 children and 192 adults. Subjects' ages varied from newborn to 39 years. Vertebral body height and depth and sagittal canal diameter were measured and ratios were calculated. This was a cross-sectional and retrospective study.Results. Vertebral bodies grow relatively more in height than in depth, most actively at puberty. At all levels, the H/D ratio remains below 1, indicating that vertebral body depth is greater than height. The SD ratio is quite stable until 7-8 years of age and then it starts to decline slowly.Conclusions. When estimating platyspondyly, the age of the patient must be taken into consideration because vertebral body height is lower in children. Growth of the spinal canal declines after 7-8 years of age. (orig.)

The evolutionary history of vertebrate cranial placodes II. Evolution of ectodermal patterning.

Science.gov (United States)

Schlosser, Gerhard; Patthey, Cedric; Shimeld, Sebastian M

2014-05-01

Cranial placodes are evolutionary innovations of vertebrates. However, they most likely evolved by redeployment, rewiring and diversification of preexisting cell types and patterning mechanisms. In the second part of this review we compare vertebrates with other animal groups to elucidate the evolutionary history of ectodermal patterning. We show that several transcription factors have ancient bilaterian roles in dorsoventral and anteroposterior regionalisation of the ectoderm. Evidence from amphioxus suggests that ancestral chordates then concentrated neurosecretory cells in the anteriormost non-neural ectoderm. This anterior proto-placodal domain subsequently gave rise to the oral siphon primordia in tunicates (with neurosecretory cells being lost) and anterior (adenohypophyseal, olfactory, and lens) placodes of vertebrates. Likewise, tunicate atrial siphon primordia and posterior (otic, lateral line, and epibranchial) placodes of vertebrates probably evolved from a posterior proto-placodal region in the tunicate-vertebrate ancestor. Since both siphon primordia in tunicates give rise to sparse populations of sensory cells, both proto-placodal domains probably also gave rise to some sensory receptors in the tunicate-vertebrate ancestor. However, proper cranial placodes, which give rise to high density arrays of specialised sensory receptors and neurons, evolved from these domains only in the vertebrate lineage. We propose that this may have involved rewiring of the regulatory network upstream and downstream of Six1/2 and Six4/5 transcription factors and their Eya family cofactors. These proteins, which play ancient roles in neuronal differentiation were first recruited to the dorsal non-neural ectoderm in the tunicate-vertebrate ancestor but subsequently probably acquired new target genes in the vertebrate lineage, allowing them to adopt new functions in regulating proliferation and patterning of neuronal progenitors. Copyright © 2014 Elsevier Inc. All rights

Fungal osteomyelitis with vertebral re-ossification.

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O Guinn, Devon J; Serletis, Demitre; Kazemi, Noojan

2016-01-01

We present a rare case of thoracic vertebral osteomyelitis secondary to pulmonary Blastomyces dermatitides. A 27-year-old male presented with three months of chest pains and non-productive cough. Examination revealed diminished breath sounds on the right. CT/MR imaging confirmed a right-sided pre-/paravertebral soft tissue mass and destructive lytic lesions from T2 to T6. CT-guided needle biopsy confirmed granulomatous pulmonary Blastomycosis. Conservative management with antifungal therapy was initiated. Neurosurgical review confirmed no clinical or profound radiographic instability, and the patient was stabilized with TLSO bracing. Serial imaging 3 months later revealed near-resolution of the thoracic soft tissue mass, with vertebral re-ossification from T2 to T6. Fungal osteomyelitis presents a rare entity in the spectrum of spinal infections. In such cases, lytic spinal lesions are classically seen in association with a large paraspinous mass. Fungal infections of the spinal column may be treated conservatively, with surgical intervention reserved for progressive cases manifesting with neurological compromise and/or spinal column instability. Here, we found unexpected evidence for vertebral re-ossification across the affected thoracic levels (T2-6) in response to IV antibiotic therapy and conservative bracing, nearly 3 months later. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Biomonitoring of marine vertebrates in Monterey Bay using eDNA metabarcoding.

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Elizabeth A Andruszkiewicz

Full Text Available Molecular analysis of environmental DNA (eDNA can be used to assess vertebrate biodiversity in aquatic systems, but limited work has applied eDNA technologies to marine waters. Further, there is limited understanding of the spatial distribution of vertebrate eDNA in marine waters. Here, we use an eDNA metabarcoding approach to target and amplify a hypervariable region of the mitochondrial 12S rRNA gene to characterize vertebrate communities at 10 oceanographic stations spanning 45 km within the Monterey Bay National Marine Sanctuary (MBNMS. In this study, we collected three biological replicates of small volume water samples (1 L at 2 depths at each of the 10 stations. We amplified fish mitochondrial DNA using a universal primer set. We obtained 5,644,299 high quality Illumina sequence reads from the environmental samples. The sequence reads were annotated to the lowest taxonomic assignment using a bioinformatics pipeline. The eDNA survey identified, to the lowest taxonomic rank, 7 families, 3 subfamilies, 10 genera, and 72 species of vertebrates at the study sites. These 92 distinct taxa come from 33 unique marine vertebrate families. We observed significantly different vertebrate community composition between sampling depths (0 m and 20/40 m deep across all stations and significantly different communities at stations located on the continental shelf (200 m bottom depth. All but 1 family identified using eDNA metabarcoding is known to occur in MBNMS. The study informs the implementation of eDNA metabarcoding for vertebrate biomonitoring.

Improvement and Extension of Shape Evaluation Criteria in Multi-Scale Image Segmentation

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Sakamoto, M.; Honda, Y.; Kondo, A.

2016-06-01

From the last decade, the multi-scale image segmentation is getting a particular interest and practically being used for object-based image analysis. In this study, we have addressed the issues on multi-scale image segmentation, especially, in improving the performances for validity of merging and variety of derived region's shape. Firstly, we have introduced constraints on the application of spectral criterion which could suppress excessive merging between dissimilar regions. Secondly, we have extended the evaluation for smoothness criterion by modifying the definition on the extent of the object, which was brought for controlling the shape's diversity. Thirdly, we have developed new shape criterion called aspect ratio. This criterion helps to improve the reproducibility on the shape of object to be matched to the actual objectives of interest. This criterion provides constraint on the aspect ratio in the bounding box of object by keeping properties controlled with conventional shape criteria. These improvements and extensions lead to more accurate, flexible, and diverse segmentation results according to the shape characteristics of the target of interest. Furthermore, we also investigated a technique for quantitative and automatic parameterization in multi-scale image segmentation. This approach is achieved by comparing segmentation result with training area specified in advance by considering the maximization of the average area in derived objects or satisfying the evaluation index called F-measure. Thus, it has been possible to automate the parameterization that suited the objectives especially in the view point of shape's reproducibility.

Technical strategies and anatomic considerations for parapedicular access to thoracic and lumbar vertebral bodies

International Nuclear Information System (INIS)

Beall, Douglas P.; Martin, Hal D.; Stapp, Annette M.; Puckett, Timothy A.; Stechison, M.T.; Braswell, John J.

2007-01-01

To investigate and illustrate a variation on the traditional percutaneous access to the vertebral body via a parapedicular approach. An effective parapedicular access technique that could safely and reliably guide the needle tip into the center of the vertebral body was developed from cadaver dissection observations for the purpose of clinical use. A total of 102 vertebral compression fractures from T-4 to L-5 were treated via the parapedicular access at our institution between July 2005 and March 2006. There were 72 patients between the ages of 17 and 96 years (mean age: 68.2 years) who underwent treatment. The cadaver dissection revealed a relatively avascular and aneural portion of the vertebral body along the superior margin of the vertebral body-pedicle junction. A total 102 vertebral fractures were treated using the parapedicular access technique without any recognized clinical complications from the needle access or the instrumentation. The thoracic and lumbar vertebral bodies may be safely, reliably, and reproducibly accessed using a percutaneous parapedicular access technique. The technique presented represents a relatively avascular and aneural approach to vertebral body. (orig.)

Closed cervical spine trauma associated with bilateral vertebral artery injuries

NARCIS (Netherlands)

Kloen, P.; Patterson, J. D.; Wintman, B. I.; Ozuna, R. M.; Brick, G. W.

1999-01-01

Bilateral vertebral artery injuries in closed cervical spine injuries are uncommon, but early recognition and treatment are important to prevent neurological deterioration. A case of bilateral vertebral injuries in a 35-year-old motor vehicle accident victim is presented, and the current literature

Extinction risk is most acute for the world's largest and smallest vertebrates.

Science.gov (United States)

Ripple, William J; Wolf, Christopher; Newsome, Thomas M; Hoffmann, Michael; Wirsing, Aaron J; McCauley, Douglas J

2017-10-03

Extinction risk in vertebrates has been linked to large body size, but this putative relationship has only been explored for select taxa, with variable results. Using a newly assembled and taxonomically expansive database, we analyzed the relationships between extinction risk and body mass (27,647 species) and between extinction risk and range size (21,294 species) for vertebrates across six main classes. We found that the probability of being threatened was positively and significantly related to body mass for birds, cartilaginous fishes, and mammals. Bimodal relationships were evident for amphibians, reptiles, and bony fishes. Most importantly, a bimodal relationship was found across all vertebrates such that extinction risk changes around a body mass breakpoint of 0.035 kg, indicating that the lightest and heaviest vertebrates have elevated extinction risk. We also found range size to be an important predictor of the probability of being threatened, with strong negative relationships across nearly all taxa. A review of the drivers of extinction risk revealed that the heaviest vertebrates are most threatened by direct killing by humans. By contrast, the lightest vertebrates are most threatened by habitat loss and modification stemming especially from pollution, agricultural cropping, and logging. Our results offer insight into halting the ongoing wave of vertebrate extinctions by revealing the vulnerability of large and small taxa, and identifying size-specific threats. Moreover, they indicate that, without intervention, anthropogenic activities will soon precipitate a double truncation of the size distribution of the world's vertebrates, fundamentally reordering the structure of life on our planet.

MR manifestations of vertebral artery injuries in cervical spine trauma

Energy Technology Data Exchange (ETDEWEB)

Yu, Jeong Sik; Chung, Tae Sub; Kim, Young Soo; Cho, Yong Eun; Kang, Byung Chul; Kim, Dong Ik [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

1996-11-01

To assess the diagnostic efficacy of magnetic resonance (MR) imaging in the detection of a vertebral artery injury occurring from major cervical spine trauma. Conventional MR findings of 63 patients and 63 control subjects were compared to detect a possible change in the vertebral arteries resulted from trauma. Plain films, CT and clinical records were also reviewed to correlate the degree of cervical spine injury with vascular change. Nine cases of absent flow signals in vessel lumen were observed in eight patients and one was observed in the control group. Patients more frequently demonstrated other abnormalities such as intraluminal linear signals (n=3) or focal luminal narrowing (n=9) but there was no statistical significance. There was a close relationship between degree of cord damage and occlusion of the vertebral artery. Conventional MR imaging is useful in the detection of vertebral artery occlusion resulting from cervical spine trauma.

Micromechanics of the human vertebral body for forward flexion.

Science.gov (United States)

Yang, Haisheng; Nawathe, Shashank; Fields, Aaron J; Keaveny, Tony M

2012-08-09

To provide mechanistic insight into the etiology of osteoporotic wedge fractures, we investigated the spatial distribution of tissue at the highest risk of initial failure within the human vertebral body for both forward flexion and uniform compression loading conditions. Micro-CT-based linear elastic finite element analysis was used to virtually load 22 human T9 vertebral bodies in either 5° of forward flexion or uniform compression; we also ran analyses replacing the simulated compliant disc (E=8 MPa) with stiff polymethylmethacrylate (PMMA, E=2500 MPa). As expected, we found that, compared to uniform compression, forward flexion increased the overall endplate axial load on the anterior half of the vertebra and shifted the spatial distribution of high-risk tissue within the vertebra towards the anterior aspect of the vertebral body. However, despite that shift, the high-risk tissue remained primarily within the central regions of the trabecular bone and endplates, and forward flexion only slightly altered the ratio of cortical-to-trabecular load sharing at the mid-vertebral level (mean±SD for n=22: 41.3±7.4% compression; 44.1±8.2% forward flexion). When the compliant disc was replaced with PMMA, the anterior shift of high-risk tissue was much more severe. We conclude that, for a compliant disc, a moderate degree of forward flexion does not appreciably alter the spatial distribution of stress within the vertebral body. Copyright © 2012 Elsevier Ltd. All rights reserved.

A checklist of the vertebrates of Kerala State, India

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P. O. Nameer

2015-11-01

Full Text Available Following the first publication on vertebrates of India (Blanford 1888–1890, a huge wealth of information has been compiled on the vertebrate fauna of various biogeographic zones of the country, especially the Western Ghats.  The state of Kerala comprising of a land area of 38,863km2, 590km coastline, an intricate system of backwaters along the coast, tropical moist forests of the Western Ghats, the highly undulating terrain, and the tropical monsoon is a unique geographical and environmental entity rich in biodiversity.  A region-specific checklist that summarises and documents the current status of vertebrate diversity provides benchmark data for documentation and appreciation of biodiversity at regional level.  Further, with the current rate of global biodiversity loss and concordant conservation efforts, the taxonomic community has a greater responsibility to make scientific information available to scientists, policy makers, politicians, research students and all relevant stakeholders, an attempt that has been made in the present paper.  The State of Kerala has 1847 species of vertebrates in 330 families and 81 orders, of which 386 are endemic to the Western Ghats region (of the Western Ghats - Sri Lanka Hotspot, and 205 species as threatened. Six hundred and eighty species of vertebrates of Kerala have been listed in the various schedules of the Indian Wildlife (Protection Act, while 148 are listed in the different appendices of CITES.  

Post-traumatic cerebellar infarction due to vertebral artery foramina fracture: case report

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Moscote-Salazar Luis Rafael

2016-03-01

Full Text Available Posttraumatic cerebral infarction is an uncommon cause of morbidity and mortality and many studies have highlighted that trauma needs to considered as causative factor for cerebellar infarction. We present a case of cerebellar infarction in a 35 year old young patient secondary to vertebral fracture involving the vertebral foramen and vertebral artery injury. CT scan cervical spine showed C2-3 fracture on left side with fracture extending into the left vertebral foramen. A CT scan angiogram could not be performed because of poor neurological status. Possibly the infarction was due to left vertebral artery injury. Without surgical intervention prognosis of these patients remain poor. Prognosis of patients with traumatic cerebellar infarction depends on the neurological status of the patient, intrinsic parenchymal damage and more importantly extrinsic compression of the brainstem by the edematous cerebellar hemispheres.

Transmission of Ranavirus between Ectothermic Vertebrate Hosts

Science.gov (United States)

Brenes, Roberto; Gray, Matthew J.; Waltzek, Thomas B.; Wilkes, Rebecca P.; Miller, Debra L.

2014-01-01

Transmission is an essential process that contributes to the survival of pathogens. Ranaviruses are known to infect different classes of lower vertebrates including amphibians, fishes and reptiles. Differences in the likelihood of infection among ectothermic vertebrate hosts could explain the successful yearlong persistence of ranaviruses in aquatic environments. The goal of this study was to determine if transmission of a Frog Virus 3 (FV3)-like ranavirus was possible among three species from different ectothermic vertebrate classes: Cope’s gray treefrog (Hyla chrysoscelis) larvae, mosquito fish (Gambusia affinis), and red-eared slider (Trachemys scripta elegans). We housed individuals previously exposed to the FV3-like ranavirus with naïve (unexposed) individuals in containers divided by plastic mesh screen to permit water flow between subjects. Our results showed that infected gray treefrog larvae were capable of transmitting ranavirus to naïve larval conspecifics and turtles (60% and 30% infection, respectively), but not to fish. Also, infected turtles and fish transmitted ranavirus to 50% and 10% of the naïve gray treefrog larvae, respectively. Nearly all infected amphibians experienced mortality, whereas infected turtles and fish did not die. Our results demonstrate that ranavirus can be transmitted through water among ectothermic vertebrate classes, which has not been reported previously. Moreover, fish and reptiles might serve as reservoirs for ranavirus given their ability to live with subclinical infections. Subclinical infections of ranavirus in fish and aquatic turtles could contribute to the pathogen’s persistence, especially when highly susceptible hosts like amphibians are absent as a result of seasonal fluctuations in relative abundance. PMID:24667325

Transmission of ranavirus between ectothermic vertebrate hosts.

Directory of Open Access Journals (Sweden)

Roberto Brenes

Full Text Available Transmission is an essential process that contributes to the survival of pathogens. Ranaviruses are known to infect different classes of lower vertebrates including amphibians, fishes and reptiles. Differences in the likelihood of infection among ectothermic vertebrate hosts could explain the successful yearlong persistence of ranaviruses in aquatic environments. The goal of this study was to determine if transmission of a Frog Virus 3 (FV3-like ranavirus was possible among three species from different ectothermic vertebrate classes: Cope's gray treefrog (Hyla chrysoscelis larvae, mosquito fish (Gambusia affinis, and red-eared slider (Trachemys scripta elegans. We housed individuals previously exposed to the FV3-like ranavirus with naïve (unexposed individuals in containers divided by plastic mesh screen to permit water flow between subjects. Our results showed that infected gray treefrog larvae were capable of transmitting ranavirus to naïve larval conspecifics and turtles (60% and 30% infection, respectively, but not to fish. Also, infected turtles and fish transmitted ranavirus to 50% and 10% of the naïve gray treefrog larvae, respectively. Nearly all infected amphibians experienced mortality, whereas infected turtles and fish did not die. Our results demonstrate that ranavirus can be transmitted through water among ectothermic vertebrate classes, which has not been reported previously. Moreover, fish and reptiles might serve as reservoirs for ranavirus given their ability to live with subclinical infections. Subclinical infections of ranavirus in fish and aquatic turtles could contribute to the pathogen's persistence, especially when highly susceptible hosts like amphibians are absent as a result of seasonal fluctuations in relative abundance.

Radiotherapy for vertebral metastases. Analysis of symptoms and clinical effects by MR imaging

International Nuclear Information System (INIS)

Sugiyama, Akira

1994-01-01

Fifty patients with 63 symptomatic vertebral metastasis (18 sites: pain only, 28 sites: radiculopathy with pain, 17 sites: myelopathy) were treated by radiotherapy. Primary lesions were located in the lung (9 cases), breast (9), colorectal area (9), prostate (7) and so on. We correlated the radiologic findings, symptoms and clinical effects with metastatic features which were classified into 4 types by MR imaging: non-deformity, expanding, vertebral collapse, and destructive mass. Each type of metastasis was accompanied with or without epidural tumor. Osteolytic metastases were apt to create features of deformity (expanding type: 18 vertebrae, vertebral collapse type: 17, destructive mass type: 9). The features of osteoblastic metastases were no deformity (18 vertebrae) and expanding type (2). The symptom of pain only occurred most frequently in the lumbosacral spine. The vertebral body deformity of symptomatic sites was relatively slight (non-deformity type: 6 sites, expanding type: 6, vertebral collapse type: 6), and epidural tumors were seen at only 2 sites. The effect of radiotherapy was excellent (complete pain relief: 64.7%, partial pain relief: 29.4%). Radiculopathy occurred most frequently in the lumber spine. Vertebral body deformity was noted in most symptomatic sites (expanding type: 9 sites, vertebral collapse type: 10, destructive mass type: 2). Complete relief was obtained in 6 sites (22.2%), partial relief in 18 (63.0%). Myelopathy occurred most often in the thoracic spine, followed by the lumbar spine. The vertebral body deformity was severe (expanding: 3 cases, vertebral collapse type: 3, destructive mass type: 6). Epidural tumors were also present in all but one case. Six of 13 patients treated with radiation alone improved. These 6 patients had non-deformity or expanding types with epidural tumor. No improvement was seen in the vertebral collapse type with epidural tumor or destructive mass type. (author)

Giant Vertebral Notochordal Rest: Magnetic Resonance and Diffusion Weighted Imaging Findings

International Nuclear Information System (INIS)

Oner, Ali Yusuf; Akpek, Sergin; Tali, Turgut; Ucar, Murat

2009-01-01

A giant vertebral notochordal rest is a newly described, benign entity that is easily confused with a vertebral chordoma. As microscopic notochordal rests are rarely found in adult autopsies, the finding of a macroscopic vertebral lesion is a new entity with only seven previously presented cases. We report here radiological findings, including diffusion weighted images, of a patient with a giant notochordal remnant confined to the L5 vertebra, with an emphasis on its distinction from a chordoma

Evolution of neural crest and placodes: amphioxus as a model for the ancestral vertebrate?

Science.gov (United States)

Holland, L. Z.; Holland, N. D.

2001-01-01

Recent studies of protochordates (ascidian tunicates and amphioxus) have given insights into possible ancestors of 2 of the characteristic features of the vertebrate head: neural crest and placodes. The neural crest probably evolved from cells on either side of the neural plate-epidermis boundary in a protochordate ancestral to the vertebrates. In amphioxus, homologues of several vertebrate neural crest marker genes (BMP2/4, Pax3/7, Msx, Dll and Snail) are expressed at the edges of the neural plate and/or adjacent nonneural ectoderm. Some of these markers are also similarly expressed in tunicates. In protochordates, however, these cells, unlike vertebrate neural crest, neither migrate as individuals through embryonic tissues nor differentiate into a wide spectrum of cell types. Therefore, while the protochordate ancestor of the vertebrates probably had the beginnings of a genetic programme for neural crest formation, this programme was augmented in the earliest vertebrates to attain definitive neural crest. Clear homologues of vertebrate placodes are lacking in protochordates. However, both amphioxus and tunicates have ectodermal sensory cells. In tunicates these are all primary neurons, sending axons to the central nervous system, while in amphioxus, the ectodermal sensory cells include both primary neurons and secondary neurons lacking axons. Comparisons of developmental gene expression suggest that the anterior ectoderm in amphioxus may be homologous to the vertebrate olfactory placode, the only vertebrate placode with primary, not secondary, neurons. Similarly, biochemical, morphological and gene expression data suggest that amphioxus and tunicates also have homologues of the adenohypophysis, one of the few vertebrate structures derived from nonneurogenic placodes. In contrast, the origin of the other vertebrate placodes is very uncertain.

The largest Silurian vertebrate and its palaeoecological implications

Science.gov (United States)

Choo, Brian; Zhu, Min; Zhao, Wenjin; Jia, Liaotao; Zhu, You'an

2014-01-01

An apparent absence of Silurian fishes more than half-a-metre in length has been viewed as evidence that gnathostomes were restricted in size and diversity prior to the Devonian. Here we describe the largest pre-Devonian vertebrate (Megamastax amblyodus gen. et sp. nov.), a predatory marine osteichthyan from the Silurian Kuanti Formation (late Ludlow, ~423 million years ago) of Yunnan, China, with an estimated length of about 1 meter. The unusual dentition of the new form suggests a durophagous diet which, combined with its large size, indicates a considerable degree of trophic specialisation among early osteichthyans. The lack of large Silurian vertebrates has recently been used as constraint in palaeoatmospheric modelling, with purported lower oxygen levels imposing a physiological size limit. Regardless of the exact causal relationship between oxygen availability and evolutionary success, this finding refutes the assumption that pre-Emsian vertebrates were restricted to small body sizes. PMID:24921626

Vertebral morphology influences the development of Schmorl's nodes in the lower thoracic vertebrae.

Science.gov (United States)

Plomp, Kimberly A; Roberts, Charlotte A; Viðarsdóttir, Una Strand

2012-12-01

Schmorl's nodes are the result of herniations of the nucleus pulposus into the adjacent vertebral body and are commonly identified in both clinical and archaeological contexts. The current study aims to identify aspects of vertebral shape that correlate with Schmorl's nodes. Two-dimensional statistical shape analysis was performed on digital images of the lower thoracic spine (T10-T12) of adult skeletons from the late medieval skeletal assemblages from Fishergate House, York, St. Mary Graces and East Smithfield Black Death cemeteries, London, and postmedieval Chelsea Old Church, London. Schmorl's nodes were scored on the basis of their location, depth, and size. Results indicate that there is a correlation between the shape of the posterior margin of the vertebral body and pedicles and the presence of Schmorl's nodes in the lower thoracic spine. The size of the vertebral body in males was also found to correlate with the lesions. Vertebral shape differences associated with the macroscopic characteristics of Schmorl's nodes, indicating severity of the lesion, were also analyzed. The shape of the pedicles and the posterior margin of the vertebral body, along with a larger vertebral body size in males, have a strong association with both the presence and severity of Schmorl's nodes. This suggests that shape and/or size of these vertebral components are predisposing to, or resulting in, vertically directed disc herniation. Copyright © 2012 Wiley Periodicals, Inc.

Electronic Gaming Machine (EGM) Environments: Market Segments and Risk.

Science.gov (United States)

Rockloff, Matthew; Moskovsky, Neda; Thorne, Hannah; Browne, Matthew; Bryden, Gabrielle

2017-12-01

This study used a marketing-research paradigm to explore gamblers' attraction to EGMs based on different elements of the environment. A select set of environmental features was sourced from a prior study (Thorne et al. in J Gambl Issues 2016b), and a discrete choice experiment was conducted through an online survey. Using the same dataset first described by Rockloff et al. (EGM Environments that contribute to excess consumption and harm, 2015), a sample of 245 EGM gamblers were sourced from clubs in Victoria, Australia, and 7516 gamblers from an Australian national online survey-panel. Participants' choices amongst sets of hypothetical gambling environments allowed for an estimation of the implied individual-level utilities for each feature (e.g., general sounds, location, etc.). K-means clustering on these utilities identified four unique market segments for EGM gambling, representing four different types of consumers. The segments were named according to their dominant features: Social, Value, High Roller and Internet. We found that the environments orientated towards the Social and Value segments were most conducive to attracting players with relatively few gambling problems, while the High Roller and Internet-focused environments had greater appeal for players with problems and vulnerabilities. This study has generated new insights into the kinds of gambling environments that are most consistent with safe play.

Percutaneous vertebroplasty in the treatment of vertebral body compression fracture secondary to osteogenesis imperfecta

International Nuclear Information System (INIS)

Rami, Parag M.; Heatwole, Eric V.; Boorstein, Jeffrey M.; McGraw, Kevin J.

2002-01-01

Percutaneous vertebroplasty, a minimally invasive interventional radiological procedure, has recently been used effectively for the treatment of symptomatic vertebral body compression fractures. Primary indications for vertebroplasty include osteoporotic compression fracture, osteolytic vertebral metastasis and myeloma, and vertebral hemangioma. We present a case and extend the indication of percutaneous vertebroplasty in a patient with a vertebral body compression fracture secondary to osteogenesis imperfecta. (orig.)

Percutaneous vertebroplasty in the treatment of vertebral body compression fracture secondary to osteogenesis imperfecta

Energy Technology Data Exchange (ETDEWEB)

Rami, Parag M.; Heatwole, Eric V.; Boorstein, Jeffrey M. [Center for Vascular and Interventional Radiology, St. Vincent Mercy Medical Center, Toledo, OH (United States); McGraw, Kevin J. [Riverside Methodist Hospital, Columbus, OH (United States)

2002-03-01

Percutaneous vertebroplasty, a minimally invasive interventional radiological procedure, has recently been used effectively for the treatment of symptomatic vertebral body compression fractures. Primary indications for vertebroplasty include osteoporotic compression fracture, osteolytic vertebral metastasis and myeloma, and vertebral hemangioma. We present a case and extend the indication of percutaneous vertebroplasty in a patient with a vertebral body compression fracture secondary to osteogenesis imperfecta. (orig.)

ACTIVATION PARAMETERS AND EXCESS THERMODYANAMIC ...

African Journals Online (AJOL)

Applying these data, viscosity-B-coefficients, activation parameters (Δμ10≠) and (Δμ20≠) and excess thermodynamic functions, viz., excess molar volume (VE), excess viscosity, ηE and excess molar free energy of activation of flow, (GE) were calculated. The value of interaction parameter, d, of Grunberg and Nissan ...

Software for hyperspectral, joint photographic experts group (.JPG), portable network graphics (.PNG) and tagged image file format (.TIFF) segmentation

Science.gov (United States)

Bruno, L. S.; Rodrigo, B. P.; Lucio, A. de C. Jorge

2016-10-01

This paper presents a system developed by an application of a neural network Multilayer Perceptron for drone acquired agricultural image segmentation. This application allows a supervised user training the classes that will posteriorly be interpreted by neural network. These classes will be generated manually with pre-selected attributes in the application. After the attribute selection a segmentation process is made to allow the relevant information extraction for different types of images, RGB or Hyperspectral. The application allows extracting the geographical coordinates from the image metadata, geo referencing all pixels on the image. In spite of excessive memory consume on hyperspectral images regions of interest, is possible to perform segmentation, using bands chosen by user that can be combined in different ways to obtain different results.

Decreased Vertebral Artery Hemodynamics in Patients with Loss of Cervical Lordosis.

Science.gov (United States)

Bulut, Mehmet Deniz; Alpayci, Mahmut; Şenköy, Emre; Bora, Aydin; Yazmalar, Levent; Yavuz, Alpaslan; Gülşen, İsmail

2016-02-15

BACKGROUND Because loss of cervical lordosis leads to disrupted biomechanics, the natural lordotic curvature is considered to be an ideal posture for the cervical spine. The vertebral arteries proceed in the transverse foramen of each cervical vertebra. Considering that the vertebral arteries travel in close anatomical relationship to the cervical spine, we speculated that the loss of cervical lordosis may affect vertebral artery hemodynamics. The aim of this study was to compare the vertebral artery values between subjects with and without loss of cervical lordosis. MATERIAL AND METHODS Thirty patients with loss of cervical lordosis and 30 controls matched for age, sex, and body mass index were included in the study. Sixty vertebral arteries in patients with loss of cervical lordosis and 60 in controls without loss of cervical lordosis were evaluated by Doppler ultrasonography. Vertebral artery hemodynamics, including lumen diameter, flow volume, peak systolic velocity, end-diastolic velocity, and resistive index, were measured, and determined values were statistically compared between the patient and the control groups. RESULTS The means of diameter (p=0.003), flow volume (p=0.002), and peak systolic velocity (p=0.014) in patients were significantly lower as compared to controls. However, there was no significant difference between the 2 groups in terms of the end-diastolic velocity (p=0.276) and resistive index (p=0.536) parameters. CONCLUSIONS The present study revealed a significant association between loss of cervical lordosis and decreased vertebral artery hemodynamics, including diameter, flow volume, and peak systolic velocity. Further studies are required to confirm these findings and to investigate their possible clinical implications.

Phylostratigraphic profiles in zebrafish uncover chordate origins of the vertebrate brain.

Science.gov (United States)

Šestak, Martin Sebastijan; Domazet-Lošo, Tomislav

2015-02-01

An elaborated tripartite brain is considered one of the important innovations of vertebrates. Other extant chordate groups have a more basic brain organization. For instance, cephalochordates possess a relatively simple brain possibly homologous to the vertebrate forebrain and hindbrain, whereas tunicates display the tripartite organization, but without the specialized brain centers. The difference in anatomical complexity is even more pronounced if one compares chordates with other deuterostomes that have only a diffuse nerve net or alternatively a rather simple central nervous system. To gain a new perspective on the evolutionary roots of the complex vertebrate brain, we made here a phylostratigraphic analysis of gene expression patterns in the developing zebrafish (Danio rerio). The recovered adaptive landscape revealed three important periods in the evolutionary history of the zebrafish brain. The oldest period corresponds to preadaptive events in the first metazoans and the emergence of the nervous system at the metazoan-eumetazoan transition. The origin of chordates marks the next phase, where we found the overall strongest adaptive imprint in almost all analyzed brain regions. This finding supports the idea that the vertebrate brain evolved independently of the brains within the protostome lineage. Finally, at the origin of vertebrates we detected a pronounced signal coming from the dorsal telencephalon, in agreement with classical theories that consider this part of the cerebrum a genuine vertebrate innovation. Taken together, these results reveal a stepwise adaptive history of the vertebrate brain where most of its extant organization was already present in the chordate ancestor. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Trends in Medicinal Uses of Edible Wild Vertebrates in Brazil

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Rômulo Romeu Nóbrega Alves

2017-01-01

Full Text Available The use of food medicines is a widespread practice worldwide. In Brazil, such use is often associated with wild animals, mostly focusing on vertebrate species. Here we assessed taxonomic and ecological trends in traditional uses of wild edible vertebrates in the country, through an extensive ethnobiological database analysis. Our results showed that at least 165 health conditions are reportedly treated by edible vertebrate species (n=204, mostly fishes and mammals. However, reptiles stand out presenting a higher plasticity in the treatment of multiple health conditions. Considering the 20 disease categories recorded, treatment prescriptions were similar within continental (i.e., terrestrial and freshwater and also within coastal and marine habitats, which may reflect locally related trends in occurrence and use of the medicinal fauna. The comprehension of the multiplicity and trends in the therapeutic uses of Brazilian vertebrates is of particular interest from a conservation perspective, as several threatened species were recorded.

Relationship between cervical vertebral maturation and mandibular growth.

Science.gov (United States)

Ball, Gina; Woodside, Donald; Tompson, Bryan; Hunter, W Stuart; Posluns, James

2011-05-01

The cervical vertebrae have been proposed as a method of determining biologic maturity. The purposes of this study were to establish a pattern of mandibular growth and to relate this pattern to the stages of cervical vertebral maturation. Cephalometric radiographs, taken annually from ages 9 to 18 years, were evaluated for 90 boys from the Burlington Growth Center, Toronto, Ontario, Canada. Mandibular lengths were measured from articulare to gnathion, and incremental growth was determined. Cervical vertebral maturation stages were assessed by using a 6-stage method. Advanced, average, and delayed maturation groups were established. The prepubertal mandibular growth minimum velocity occurred during cervical stages 1 through 4 (P = 0.7327). Peak mandibular growth velocity occurred most frequently during stage 4 in all 3 maturation groups, with a statistical difference in the average and delayed groups (P cervical stages 1 through 6 does not occur annually; time spent in each stage varies depending on the stage and the maturation group. Cervical vertebral maturation stages cannot accurately identify the mandibular prepubertal growth minimum and therefore cannot predict the onset of the peak in mandibular growth. The cervical vertebral maturation stages should be used with other methods of biologic maturity assessment when considering both dentofacial orthopedic treatment and orthognathic surgery. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Temporal trends in vertebral size and shape from medieval to modern-day.

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Juho-Antti Junno

Full Text Available Human lumbar vertebrae support the weight of the upper body. Loads lifted and carried by the upper extremities cause significant loading stress to the vertebral bodies. It is well established that trauma-induced vertebral fractures are common especially among elderly people. The aim of this study was to investigate the morphological factors that could have affected the prevalence of trauma-related vertebral fractures from medieval times to the present day. To determine if morphological differences existed in the size and shape of the vertebral body between medieval times and the present day, the vertebral body size and shape was measured from the 4th lumbar vertebra using magnetic resonance imaging (MRI and standard osteometric calipers. The modern samples consisted of modern Finns and the medieval samples were from archaeological collections in Sweden and Britain. The results show that the shape and size of the 4th lumbar vertebra has changed significantly from medieval times in a way that markedly affects the biomechanical characteristics of the lumbar vertebral column. These changes may have influenced the incidence of trauma- induced spinal fractures in modern populations.

Lesões ocupacionais afetando a coluna vertebral em trabalhadores de enfermagem Lesiones ocupacionales de la columna vertebral en trabajadores de enfermería Vertebral column trauma caused by occupational accidents involving members of the nursing team

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Elisandra de Oliveira Parada

2002-01-01

Full Text Available Através do levantamento das comunicações de acidente do trabalho (CAT de um hospital universitário no período de janeiro de 1990 a dezembro de 1997, analisou-se determinadas características da ocorrência de acidentes do trabalho relacionados com a coluna vertebral em trabalhadores de enfermagem. Verificou-se que nesse período foram notificados 531 acidentes e 37 (7,0% destes eram acidentes típicos que comprometeram a coluna vertebral. Os resultados indicam subnotificação do acidente e que a categoria mais acometida foi o atendente de enfermagem. Os acidentes ocorreram principalmente pela movimentação e transporte de equipamentos e pacientes e pelas quedas.A través de los reportes de accidentes de trabajo (RAT de un Hospital Universitario en el periodo de enero de 1990 a diciembre de 1997, se analizaron determinadas características de la ocurrencia de accidentes de trabajo relacionados con la columna vertebral en trabajadores de enfermería. Se verificó que en ese periodo fueron notificados 531 accidentes y 37 (7,0% eran accidentes típicos que comprometieron la columna vertebral. Los resultados indican la subnotificación del accidente y que la categoría más afectada fue la de ayudante de enfermería. Los accidentes ocurrieron principalmente por el movimiento y traslado de equipos y pacientes y también por las caídas.All occupational accidents (CAT reported at a University hospital, from January 1990 to December 1997, were analyzed and the characteristics of the vertebral column trauma caused by the occupational accidents involving members of the nursing team were investigated. During this period, 531 accidents were reported and 37 (7% of these were typical vertebral column traumas. These results suggested that the number of accidents reported were below actual estimates and that the nursing auxiliaries were the most affected. The accidents were mainly caused by falls and during the transport or transfer of patients and

MRI evaluation and treatment of osteoporotic vertebral compression fracture

International Nuclear Information System (INIS)

Yamaguchi, Ken; Otani, Koji

2003-01-01

The purpose of this study was to investigate the relation between Gd-DTPA enhanced MRI findings and the prognosis of the fractured vertebral body in the patients with fresh osteoporotic compression vertebral fractures. Subjects were 8 cases, 11 vertebrae. All of the cases were treated with no bed rest and no corset. MRI and radiographs were taken within 1 week after injury. MRI signal intensity of the fractured vertebral body altered low on T1WI at acute phase. When the fractured vertebrae were enhanced at whole area with Gd-DTPA at acute phase, the vertebrae showed no progression of wedge deformity by follow up radiographs. On the other hand, when the fractured vertebrae were not enhanced at whole area, the vertebrae showed progression of wedge deformity. These findings suggests that vertebral fractures in osteoporosis should be taken MRI including GD-DTPA in acute phase after injury. When the fractured vertebrae are enhanced with Gd-DTPA in whole body at acute phase, the fracture may need no special treatment. In conclusion, Gd-DTPA enhanced MRI may be useful to determine the prognosis of the osteoporotic compression fracture. (author)

Correlation between cervical vertebral and dental maturity in Iranian subjects.

Science.gov (United States)

Heravi, Farzin; Imanimoghaddam, Mahrokh; Rahimi, Hoda

2011-12-01

Determination of the skeletal maturation is extremely important in clinical orthodontics. Cervical vertebral maturation is an effective diagnostic tool for determining the adolescent growth spurt. The aim of this study was to investigate the correlation between the stages of calcification of teeth and the cervical vertebral maturity stages.

Comparative studies of vertebrate endothelin-converting enzyme-like 1 genes and proteins

Directory of Open Access Journals (Sweden)

Holmes RS

2013-01-01

Full Text Available Roger S Holmes,1,2 Laura A Cox11Department of Genetics and Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA; 2Eskitis Institute for Cell and Molecular Therapies and School of Biomolecular and Physical Sciences, Griffith University, Nathan, Queensland, AustraliaAbstract: Endothelin-converting enzyme-like 1 (ECEL1 is a member of the M13 family of neutral endopeptidases which play an essential role in the neural regulation of vertebrate respiration. Genetic deficiency of this protein results in respiratory failure soon after birth. Comparative ECEL1 amino acid sequences and structures and ECEL1 gene locations were examined using data from several vertebrate genome projects. Vertebrate ECEL1 sequences shared 66%–99% identity as compared with 30%–63% sequence identities with other M13-like family members, ECE1, ECE2, and NEP (neprilysin or MME. Three N-glycosylation sites were conserved among most vertebrate ECEL1 proteins examined. Sequence alignments, conserved key amino acid residues, and predicted secondary and tertiary structures were also studied, including cytoplasmic, transmembrane, and luminal sequences and active site residues. Vertebrate ECEL1 genes usually contained 18 exons and 17 coding exons on the negative strand. Exons 1 and 2 of the human ECEL1 gene contained 5'-untranslated (5'-UTR regions, a large CpG island (CpG256, and several transcription factor binding sites which may contribute to the high levels of gene expression previously reported in neural tissues. Phylogenetic analyses examined the relationships and potential evolutionary origins of the vertebrate ECEL1 gene with six other vertebrate neutral endopeptidase M13 family genes. These suggested that ECEL1 originated in an ancestral vertebrate genome from a duplication event in an ancestral neutral endopeptidase M13-like gene.Keywords: vertebrates, amino acid sequence, ECEL1, ECE1, ECE2, KELL, NEP, NEPL1, PHEX

A framework for quantification and physical modeling of cell mixing applied to oscillator synchronization in vertebrate somitogenesis

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Koichiro Uriu

2017-08-01

Full Text Available In development and disease, cells move as they exchange signals. One example is found in vertebrate development, during which the timing of segment formation is set by a ‘segmentation clock’, in which oscillating gene expression is synchronized across a population of cells by Delta-Notch signaling. Delta-Notch signaling requires local cell-cell contact, but in the zebrafish embryonic tailbud, oscillating cells move rapidly, exchanging neighbors. Previous theoretical studies proposed that this relative movement or cell mixing might alter signaling and thereby enhance synchronization. However, it remains unclear whether the mixing timescale in the tissue is in the right range for this effect, because a framework to reliably measure the mixing timescale and compare it with signaling timescale is lacking. Here, we develop such a framework using a quantitative description of cell mixing without the need for an external reference frame and constructing a physical model of cell movement based on the data. Numerical simulations show that mixing with experimentally observed statistics enhances synchronization of coupled phase oscillators, suggesting that mixing in the tailbud is fast enough to affect the coherence of rhythmic gene expression. Our approach will find general application in analyzing the relative movements of communicating cells during development and disease.

The amphioxus genome illuminates vertebrate origins and cephalochordate biology

OpenAIRE

Holland, Linda Z.; Albalat, Ricard; Azumi, Kaoru; Benito-Gutiérrez, Èlia; Blow, Matthew J.; Bronner-Fraser, Marianne; Brunet, Frederic; Butts, Thomas; Candiani, Simona; Dishaw, Larry J.; Ferrier, David E.K.; Garcia-Fernàndez, Jordi; Gibson-Brown, Jeremy J.; Gissi, Carmela; Godzik, Adam

2008-01-01

Cephalochordates, urochordates, and vertebrates evolved from a common ancestor over 520 million years ago. To improve our understanding of chordate evolution and the origin of vertebrates, we intensively searched for particular genes, gene families, and conserved noncoding elements in the sequenced genome of the cephalochordate Branchiostoma floridae, commonly called amphioxus or lancelets. Special attention was given to homeobox genes, opsin genes, genes involved in neural crest development,...

Zfp462 deficiency causes anxiety-like behaviors with excessive self-grooming in mice.

Science.gov (United States)

Wang, B; Zheng, Y; Shi, H; Du, X; Zhang, Y; Wei, B; Luo, M; Wang, H; Wu, X; Hua, X; Sun, M; Xu, X

2017-02-01

Zfp462 is a newly identified vertebrate-specific zinc finger protein that contains nearly 2500 amino acids and 23 putative C2H2-type zinc finger domains. So far, the functions of Zfp462 remain unclear. In our study, we showed that Zfp462 is expressed predominantly in the developing brain, especially in the cerebral cortex and hippocampus regions from embryonic day 7.5 to early postnatal stage. By using a piggyBac transposon-generated Zfp462 knockout (KO) mouse model, we found that Zfp462 KO mice exhibited prenatal lethality with normal neural tube patterning, whereas heterozygous (Het) Zfp462 KO (Zfp462 +/- ) mice showed developmental delay with low body weight and brain weight. Behavioral studies showed that Zfp462 +/- mice presented anxiety-like behaviors with excessive self-grooming and hair loss, which were similar to the pathological grooming behaviors in Hoxb8 KO mice. Further analysis of grooming microstructure showed the impairment of grooming patterning in Zfp462 +/- mice. In addition, the mRNA levels of Pbx1 (pre-B-cell leukemia homeobox 1, an interacting protein of Zfp462) and Hoxb8 decreased in the brains of Zfp462 +/- mice, which may be the cause of anxiety-like behaviors. Finally, imipramine, a widely used and effective anti-anxiety medicine, rescued anxiety-like behaviors and excessive self-grooming in Zfp462 +/- mice. In conclusion, Zfp462 deficiency causes anxiety-like behaviors with excessive self-grooming in mice. This provides a novel genetic mouse model for anxiety disorders and a useful tool to determine potential therapeutic targets for anxiety disorders and screen anti-anxiety drugs. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

The vertebrate fauna of Ichauway, Baker County, GA

Science.gov (United States)

Smith, L.L.; Steen, D.A.; Stober, J.M.; Freeman, Mary C.; Golladay, S.W.; Conner, L.M.; Cochrane, J.

2006-01-01

Less than 4% of the once extensive Pinus palustris (longleaf pine) ecosystem remains today. Although longleaf pine habitats are recognized for their high species diversity, few published accounts document the vertebrate faunas of remaining tracts. Here we report on the vertebrate species richness of lchauway, an 11,300-ha property in Baker County, GA. The property includes ca. 7300 ha of longleaf pine with native ground cover, along with more than 30 seasonal wetlands and ca. 45 km of riparian habitat associated with Ichawaynochaway Creek, Big Cypress Creek, and the Flint River. The fauna includes 61 species of fish, 31 amphibians, 53 reptiles, 191 birds, and 41 mammals. Despite the relative isolation of the property from other natural ecosystems, the vertebrate fauna of lchauway is remarkably diverse and may offer an example of reference conditions to guide restoration of longleaf pine forests, associated seasonal wetlands, and riparian areas elsewhere in the southeastern U S.

Nestedness of ectoparasite-vertebrate host networks.

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Sean P Graham

2009-11-01

Full Text Available Determining the structure of ectoparasite-host networks will enable disease ecologists to better understand and predict the spread of vector-borne diseases. If these networks have consistent properties, then studying the structure of well-understood networks could lead to extrapolation of these properties to others, including those that support emerging pathogens. Borrowing a quantitative measure of network structure from studies of mutualistic relationships between plants and their pollinators, we analyzed 29 ectoparasite-vertebrate host networks--including three derived from molecular bloodmeal analysis of mosquito feeding patterns--using measures of nestedness to identify non-random interactions among species. We found significant nestedness in ectoparasite-vertebrate host lists for habitats ranging from tropical rainforests to polar environments. These networks showed non-random patterns of nesting, and did not differ significantly from published estimates of nestedness from mutualistic networks. Mutualistic and antagonistic networks appear to be organized similarly, with generalized ectoparasites interacting with hosts that attract many ectoparasites and more specialized ectoparasites usually interacting with these same "generalized" hosts. This finding has implications for understanding the network dynamics of vector-born pathogens. We suggest that nestedness (rather than random ectoparasite-host associations can allow rapid transfer of pathogens throughout a network, and expand upon such concepts as the dilution effect, bridge vectors, and host switching in the context of nested ectoparasite-vertebrate host networks.

Radiotherapy of vertebral hemangiomas

International Nuclear Information System (INIS)

Sakata, Kohichi; Hareyama, Masato; Oouchi, Atushi; Sido, Mitsuo; Nagakura, Hisayasu; Tamakawa, Mituharu; Akiba, Hidenari; Morita, Kazuo

1997-01-01

Between 1975 and 1996, 14 patients (11 females, 3 males) with vertebral hemangioma received treatment with radiotherapy. Thirteen patients had a history of back pain or lumbago and 2 patients had neurological symptoms such as sensory impairment or paraplegia. The standard dose administered was 36 Gy in 18 fractions (five treatments per week). In the 13 patients with pain, this was completely or partially relieved. The condition of a man with hypesthesia of the legs deteriorated and a woman with paraplegia who was treated with decompressive laminectomy followed by radiotherapy recovered completely after irradiation. CT scan before irradiation showed thickened trabeculae as small punctate areas of sclerosis in all patients. At MR imaging before irradiation, T2-weighted MR images showed areas of high intensity in all patients and MR images demonstrated lesion enhancement. However, none of the patients who were treated successfully with radiation demonstrated any changes of the affected vertebra in the conventional radiographic films, CT scan or MR imaging, even 5 years after irradiation. Radiological imaging is indispensable for the diagnosis of vertebral hemangiomas but does not appear to be useful for evaluating the effects of radiotherapy. (orig.)

Early vertebrate origin and diversification of small transmembrane regulators of cellular ion transport.

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Pirkmajer, Sergej; Kirchner, Henriette; Lundell, Leonidas S; Zelenin, Pavel V; Zierath, Juleen R; Makarova, Kira S; Wolf, Yuri I; Chibalin, Alexander V

2017-07-15

Small transmembrane proteins such as FXYDs, which interact with Na + ,K + -ATPase, and the micropeptides that interact with sarco/endoplasmic reticulum Ca 2+ -ATPase play fundamental roles in regulation of ion transport in vertebrates. Uncertain evolutionary origins and phylogenetic relationships among these regulators of ion transport have led to inconsistencies in their classification across vertebrate species, thus hampering comparative studies of their functions. We discovered the first FXYD homologue in sea lamprey, a basal jawless vertebrate, which suggests small transmembrane regulators of ion transport emerged early in the vertebrate lineage. We also identified 13 gene subfamilies of FXYDs and propose a revised, phylogeny-based FXYD classification that is consistent across vertebrate species. These findings provide an improved framework for investigating physiological and pathophysiological functions of small transmembrane regulators of ion transport. Small transmembrane proteins are important for regulation of cellular ion transport. The most prominent among these are members of the FXYD family (FXYD1-12), which regulate Na + ,K + -ATPase, and phospholamban, sarcolipin, myoregulin and DWORF, which regulate the sarco/endoplasmic reticulum Ca 2+ -ATPase (SERCA). FXYDs and regulators of SERCA are present in fishes, as well as terrestrial vertebrates; however, their evolutionary origins and phylogenetic relationships are obscure, thus hampering comparative physiological studies. Here we discovered that sea lamprey (Petromyzon marinus), a representative of extant jawless vertebrates (Cyclostomata), expresses an FXYD homologue, which strongly suggests that FXYDs predate the emergence of fishes and other jawed vertebrates (Gnathostomata). Using a combination of sequence-based phylogenetic analysis and conservation of local chromosome context, we determined that FXYDs markedly diversified in the lineages leading to cartilaginous fishes (Chondrichthyes) and bony

Segmental kyphosis after cervical interbody fusion with stand-alone polyetheretherketone (PEEK) cages: a comparative study on 2 different PEEK cages.

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Kim, Chi Heon; Chung, Chun Kee; Jahng, Tae-Ahn; Park, Sung Bae; Sohn, Seil; Lee, Sungjoon

2015-02-01

Retrospective comparative study. Two polyetheretherketone (PEEK) cages of different designs were compared in terms of the postoperative segmental kyphosis after anterior cervical discectomy and fusion. Segmental kyphosis occasionally occurs after the use of a stand-alone cage for anterior cervical discectomy and fusion. Although PEEK material seems to have less risk of segmental kyphosis compared with other materials, the occurrence of segmental kyphosis for PEEK cages has been reported to be from 0% to 29%. There have been a few reports that addressed the issue of PEEK cage design. A total of 41 consecutive patients who underwent single-level anterior discectomy and fusion with a stand-alone cage were included. Either a round tube-type (Solis; 18 patients, S-group) or a trapezoidal tube-type (MC+; 23 patients, M-group) cage was used. The contact area between the cage and the vertebral body is larger in MC+ than in Solis, and anchoring pins were present in the Solis cage. The effect of the cage type on the segmental angle (SA) (lordosis vs. kyphosis) at postoperative month 24 was analyzed. Preoperatively, segmental lordosis was present in 12/18 S-group and 16/23 M-group patients (P=0.84). The SA was more lordotic than the preoperative angle in both groups just after surgery, with no difference between groups (P=0.39). At 24 months, segmental lordosis was observed in 9/18 S-group and 20/23 M-group patients (P=0.01). The patients in M-group were 7.83 times more likely than patients in S-group (P=0.04; odds ratio, 7.83; 95% confidence interval, 1.09-56.28) not to develop segmental kyphosis. The design of the PEEK cage used may influence the SA, and this association needs to be considered when using stand-alone PEEK cages.

Brookhaven segment interconnect

International Nuclear Information System (INIS)

Morse, W.M.; Benenson, G.; Leipuner, L.B.

1983-01-01

We have performed a high energy physics experiment using a multisegment Brookhaven FASTBUS system. The system was composed of three crate segments and two cable segments. We discuss the segment interconnect module which permits communication between the various segments

Endovascular treatment of three traumatic lesions of the vertebral artery

International Nuclear Information System (INIS)

Galvis, Victor Raul; Medina V, Francisco Jose

2007-01-01

The purpose is to expose the results of the endovascular treatment of three traumatic lesions of the vertebral artery. Methods: in the period from October 2005 to May 2006, three patients with traumatic lesions in the vertebral artery were treated by endovascular therapy with an age average of 32 years. All the procedures were carried out using subtraction digital angiography under anesthesiology supervision and were started with a 5,000 IU heparin bolus, previous antiplatelet medication with clopidogrel. For the treatment of the lesions covered stents and coils were used. results: there were three documented cases of traumatic lesions of the vertebral artery treated by endovascular therapy, in two cases arteriovenous fistulas were identified (between vertebral artery and internal jugular vein) with associated pseudo aneurysms, and in one case a pseudo aneurysm without fistula was found. The first patient was treated with placement of a covered stent, in a second patient the lesion was occluded with coils and a third patient required stent and coils with satisfactory repair of the lesions. Complications were not presented as a result of the procedures. Conclusions: the endovascular treatment for traumatic lesions of the vertebral artery is an alternative with minimum morbidity and reasonable costs avoiding the open surgery and conserving the permeability of the vessel when it is possible

MR diagnosis of cerebellar infarction due to vertebral artery dissection in children

International Nuclear Information System (INIS)

Cheon, J.E.; Kim, I.O.; Kim, W.S.; Yeon, K.M.; Hwang, Y.S.; Wang, K.C.

2001-01-01

Posterior circulation infarction is uncommon in children. We describe the clinical presentation and radiological findings in two children with cerebellar infarction resulting from dissection of the vertebral artery. We emphasize that vertebral artery injury should be considered in a child with acute symptoms and signs of ischaemia in the posterior circulation. MRI and MRA may be helpful in the diagnosis of cerebellar infarction and vertebral artery abnormality. (orig.)

Elemental markers in elasmobranchs: effects of environmental history and growth on vertebral chemistry.

Science.gov (United States)

Smith, Wade D; Miller, Jessica A; Heppell, Selina S

2013-01-01

Differences in the chemical composition of calcified skeletal structures (e.g. shells, otoliths) have proven useful for reconstructing the environmental history of many marine species. However, the extent to which ambient environmental conditions can be inferred from the elemental signatures within the vertebrae of elasmobranchs (sharks, skates, rays) has not been evaluated. To assess the relationship between water and vertebral elemental composition, we conducted two laboratory studies using round stingrays, Urobatis halleri, as a model species. First, we examined the effects of temperature (16°, 18°, 24°C) on vertebral elemental incorporation (Li/Ca, Mg/Ca, Mn/Ca, Zn/Ca, Sr/Ca, Ba/Ca). Second, we tested the relationship between water and subsequent vertebral elemental composition by manipulating dissolved barium concentrations (1x, 3x, 6x). We also evaluated the influence of natural variation in growth rate on elemental incorporation for both experiments. Finally, we examined the accuracy of classifying individuals to known environmental histories (temperature and barium treatments) using vertebral elemental composition. Temperature had strong, negative effects on the uptake of magnesium (DMg) and barium (DBa) and positively influenced manganese (DMn) incorporation. Temperature-dependent responses were not observed for lithium and strontium. Vertebral Ba/Ca was positively correlated with ambient Ba/Ca. Partition coefficients (DBa) revealed increased discrimination of barium in response to increased dissolved barium concentrations. There were no significant relationships between elemental incorporation and somatic growth or vertebral precipitation rates for any elements except Zn. Relationships between somatic growth rate and DZn were, however, inconsistent and inconclusive. Variation in the vertebral elemental signatures of U. halleri reliably distinguished individual rays from each treatment based on temperature (85%) and Ba exposure (96%) history. These

Whole genome duplications and expansion of the vertebrate GATA transcription factor gene family

Directory of Open Access Journals (Sweden)

Bowerman Bruce

2009-08-01

Full Text Available Abstract Background GATA transcription factors influence many developmental processes, including the specification of embryonic germ layers. The GATA gene family has significantly expanded in many animal lineages: whereas diverse cnidarians have only one GATA transcription factor, six GATA genes have been identified in many vertebrates, five in many insects, and eleven to thirteen in Caenorhabditis nematodes. All bilaterian animal genomes have at least one member each of two classes, GATA123 and GATA456. Results We have identified one GATA123 gene and one GATA456 gene from the genomic sequence of two invertebrate deuterostomes, a cephalochordate (Branchiostoma floridae and a hemichordate (Saccoglossus kowalevskii. We also have confirmed the presence of six GATA genes in all vertebrate genomes, as well as additional GATA genes in teleost fish. Analyses of conserved sequence motifs and of changes to the exon-intron structure, and molecular phylogenetic analyses of these deuterostome GATA genes support their origin from two ancestral deuterostome genes, one GATA 123 and one GATA456. Comparison of the conserved genomic organization across vertebrates identified eighteen paralogous gene families linked to multiple vertebrate GATA genes (GATA paralogons, providing the strongest evidence yet for expansion of vertebrate GATA gene families via genome duplication events. Conclusion From our analysis, we infer the evolutionary birth order and relationships among vertebrate GATA transcription factors, and define their expansion via multiple rounds of whole genome duplication events. As the genomes of four independent invertebrate deuterostome lineages contain single copy GATA123 and GATA456 genes, we infer that the 0R (pre-genome duplication invertebrate deuterostome ancestor also had two GATA genes, one of each class. Synteny analyses identify duplications of paralogous chromosomal regions (paralogons, from single ancestral vertebrate GATA123 and GATA456

The 'Tully monster' is a vertebrate.

Science.gov (United States)

McCoy, Victoria E; Saupe, Erin E; Lamsdell, James C; Tarhan, Lidya G; McMahon, Sean; Lidgard, Scott; Mayer, Paul; Whalen, Christopher D; Soriano, Carmen; Finney, Lydia; Vogt, Stefan; Clark, Elizabeth G; Anderson, Ross P; Petermann, Holger; Locatelli, Emma R; Briggs, Derek E G

2016-04-28

Problematic fossils, extinct taxa of enigmatic morphology that cannot be assigned to a known major group, were once a major issue in palaeontology. A long-favoured solution to the 'problem of the problematica', particularly the 'weird wonders' of the Cambrian Burgess Shale, was to consider them representatives of extinct phyla. A combination of new evidence and modern approaches to phylogenetic analysis has now resolved the affinities of most of these forms. Perhaps the most notable exception is Tullimonstrum gregarium, popularly known as the Tully monster, a large soft-bodied organism from the late Carboniferous Mazon Creek biota (approximately 309-307 million years ago) of Illinois, USA, which was designated the official state fossil of Illinois in 1989. Its phylogenetic position has remained uncertain and it has been compared with nemerteans, polychaetes, gastropods, conodonts, and the stem arthropod Opabinia. Here we review the morphology of Tullimonstrum based on an analysis of more than 1,200 specimens. We find that the anterior proboscis ends in a buccal apparatus containing teeth, the eyes project laterally on a long rigid bar, and the elongate segmented body bears a caudal fin with dorsal and ventral lobes. We describe new evidence for a notochord, cartilaginous arcualia, gill pouches, articulations within the proboscis, and multiple tooth rows adjacent to the mouth. This combination of characters, supported by phylogenetic analysis, identifies Tullimonstrum as a vertebrate, and places it on the stem lineage to lampreys (Petromyzontida). In addition to increasing the known morphological disparity of extinct lampreys, a chordate affinity for T. gregarium resolves the nature of a soft-bodied fossil which has been debated for more than 50 years.

Lumbo-costo-vertebral syndrome with congenital lumbar hernia.

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Gupta, Lucky; Mala, Tariq Ahmed; Gupta, Rahul; Malla, Shahid Amin

2014-01-01

Lumbo-costo-vertebral syndrome (LCVS) is a set of rare abnormalities involving vertebral bodies, ribs, and abdominal wall. We present a case of LCVS in a 2-year-old girl who had a progressive swelling over left lumbar area noted for the last 12 months. Clinical examination revealed a reducible swelling with positive cough impulse. Ultrasonography showed a defect containing bowel loops in the left lumbar region. Chest x-ray showed scoliosis and hemivertebrae with absent lower ribs on left side. Meshplasty was done.

Nocardia brasiliensis vertebral osteomyelitis and epidural abscess.

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Johnson, Philip; Ammar, Hussam

2013-04-11

Nocardia species exist in the environment as a saprophyte; it is found worldwide in soil and decaying plant matter. They often infect patients with underlying immune compromise, pulmonary disease or history of trauma or surgery. The diagnosis of nocardiosis can be easily missed as it mimics many other granulomatous and neoplastic disease. We report a 69-year-old man who presented with chronic back pain and paraparesis. He was found to have Nocardial brasiliensis vertebral osteomyelitis and epidural abscess. Laminectomy and epidural wash out was performed but with no neurological recovery. This is the second reported case of N brasiliensis vertebral osteomyelitis in the literature.

Active Segmentation.

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Mishra, Ajay; Aloimonos, Yiannis

2009-01-01

The human visual system observes and understands a scene/image by making a series of fixations. Every fixation point lies inside a particular region of arbitrary shape and size in the scene which can either be an object or just a part of it. We define as a basic segmentation problem the task of segmenting that region containing the fixation point. Segmenting the region containing the fixation is equivalent to finding the enclosing contour- a connected set of boundary edge fragments in the edge map of the scene - around the fixation. This enclosing contour should be a depth boundary.We present here a novel algorithm that finds this bounding contour and achieves the segmentation of one object, given the fixation. The proposed segmentation framework combines monocular cues (color/intensity/texture) with stereo and/or motion, in a cue independent manner. The semantic robots of the immediate future will be able to use this algorithm to automatically find objects in any environment. The capability of automatically segmenting objects in their visual field can bring the visual processing to the next level. Our approach is different from current approaches. While existing work attempts to segment the whole scene at once into many areas, we segment only one image region, specifically the one containing the fixation point. Experiments with real imagery collected by our active robot and from the known databases 1 demonstrate the promise of the approach.

Patterns and Processes of Vertebrate Evolution

Science.gov (United States)

Carroll, Robert Lynn

1997-04-01

This new text provides an integrated view of the forces that influence the patterns and rates of vertebrate evolution from the level of living populations and species to those that resulted in the origin of the major vertebrate groups. The evolutionary roles of behavior, development, continental drift, and mass extinctions are compared with the importance of variation and natural selection that were emphasized by Darwin. It is extensively illustrated, showing major transitions between fish and amphibians, dinosaurs and birds, and land mammals to whales. No book since Simpson's Major Features of Evolution has attempted such a broad study of the patterns and forces of evolutionary change. Undergraduate students taking a general or advanced course on evolution, and graduate students and professionals in evolutionary biology and paleontology will find the book of great interest.

Spatial complexity of carcass location influences vertebrate scavenger efficiency and species composition.

Science.gov (United States)

Smith, Joshua B; Laatsch, Lauren J; Beasley, James C

2017-08-31

Scavenging plays an important role in shaping communities through inter- and intra-specific interactions. Although vertebrate scavenger efficiency and species composition is likely influenced by the spatial complexity of environments, heterogeneity in carrion distribution has largely been disregarded in scavenging studies. We tested this hypothesis by experimentally placing juvenile bird carcasses on the ground and in nests in trees to simulate scenarios of nestling bird carrion availability. We used cameras to record scavengers removing carcasses and elapsed time to removal. Carrion placed on the ground was scavenged by a greater diversity of vertebrates and at > 2 times the rate of arboreal carcasses, suggesting arboreal carrion may represent an important resource to invertebrate scavengers, particularly in landscapes with efficient vertebrate scavenging communities. Nonetheless, six vertebrate species scavenged arboreal carcasses. Rat snakes (Elaphe obsolete), which exclusively scavenged from trees, and turkey vultures (Cathartes aura) were the primary scavengers of arboreal carrion, suggesting such resources are potentially an important pathway of nutrient acquisition for some volant and scansorial vertebrates. Our results highlight the intricacy of carrion-derived food web linkages, and how consideration of spatial complexity in carcass distribution (i.e., arboreal) may reveal important pathways of nutrient acquisition by invertebrate and vertebrate scavenging guilds.

Excess Entropy and Diffusivity

Indian Academy of Sciences (India)

First page Back Continue Last page Graphics. Excess Entropy and Diffusivity. Excess entropy scaling of diffusivity (Rosenfeld,1977). Analogous relationships also exist for viscosity and thermal conductivity.

IMPROVEMENT AND EXTENSION OF SHAPE EVALUATION CRITERIA IN MULTI-SCALE IMAGE SEGMENTATION

Directory of Open Access Journals (Sweden)

M. Sakamoto

2016-06-01

Full Text Available From the last decade, the multi-scale image segmentation is getting a particular interest and practically being used for object-based image analysis. In this study, we have addressed the issues on multi-scale image segmentation, especially, in improving the performances for validity of merging and variety of derived region’s shape. Firstly, we have introduced constraints on the application of spectral criterion which could suppress excessive merging between dissimilar regions. Secondly, we have extended the evaluation for smoothness criterion by modifying the definition on the extent of the object, which was brought for controlling the shape’s diversity. Thirdly, we have developed new shape criterion called aspect ratio. This criterion helps to improve the reproducibility on the shape of object to be matched to the actual objectives of interest. This criterion provides constraint on the aspect ratio in the bounding box of object by keeping properties controlled with conventional shape criteria. These improvements and extensions lead to more accurate, flexible, and diverse segmentation results according to the shape characteristics of the target of interest. Furthermore, we also investigated a technique for quantitative and automatic parameterization in multi-scale image segmentation. This approach is achieved by comparing segmentation result with training area specified in advance by considering the maximization of the average area in derived objects or satisfying the evaluation index called F-measure. Thus, it has been possible to automate the parameterization that suited the objectives especially in the view point of shape’s reproducibility.

24 CFR 236.60 - Excess Income.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Excess Income. 236.60 Section 236... § 236.60 Excess Income. (a) Definition. Excess Income consists of cash collected as rent from the... Rent. The unit-by-unit requirement necessitates that, if a unit has Excess Income, the Excess Income...

Checklist of vertebrate animals of the Cascade Head Experimental Forest.

Science.gov (United States)

Chris Maser; Jerry F. Franklin

1974-01-01

Three months, April and August 1971 and August 1972, were spent studying the vertebrate fauna of Cascade Head Experimental Forest. The resulting annotated checklist includes 9 amphibians, 2 reptiles, 35 birds, and 40 mammals. A standardized animal habitat classification is presented in an effort to correlate the vertebrates in some meaningful way to their environment...

The application of data measurement before the pedicle vertebral arch fixed operation with spiral CT

International Nuclear Information System (INIS)

Yang Zenian; Luo Zhongyao; Chen Yong'an

2003-01-01

Objective: Authors carry out volume scans and 3D surface reconstruction. Then authors get the precise data of pedicle of vertebral arch, entering nail angle on horizontal direction, entering nail screw length, and the smallest horizontal diameter and entering nails' distance on pedicle of vertebral arch before the pedicle vertebral arch fixed operation. Method: Select the axial image of the widest pedicle of vertebral arch and it SSD image, measure the entering nail distance on the pedicle of vertebral arch, TSA, entering nail screw length, and the smallest horizontal diameter of the pedicle of vertebral arch. Result: The method helps to prepare the length, size and location of the nail and TSA for the pedicle of vertebral arch fixed operation, increase the operation success rate. Conclusion: This is a simple and reliable method to prepare the precise data of the nail length and size, TSA for the operation

GeoSegmenter: A statistically learned Chinese word segmenter for the geoscience domain

Science.gov (United States)

Huang, Lan; Du, Youfu; Chen, Gongyang

2015-03-01

Unlike English, the Chinese language has no space between words. Segmenting texts into words, known as the Chinese word segmentation (CWS) problem, thus becomes a fundamental issue for processing Chinese documents and the first step in many text mining applications, including information retrieval, machine translation and knowledge acquisition. However, for the geoscience subject domain, the CWS problem remains unsolved. Although a generic segmenter can be applied to process geoscience documents, they lack the domain specific knowledge and consequently their segmentation accuracy drops dramatically. This motivated us to develop a segmenter specifically for the geoscience subject domain: the GeoSegmenter. We first proposed a generic two-step framework for domain specific CWS. Following this framework, we built GeoSegmenter using conditional random fields, a principled statistical framework for sequence learning. Specifically, GeoSegmenter first identifies general terms by using a generic baseline segmenter. Then it recognises geoscience terms by learning and applying a model that can transform the initial segmentation into the goal segmentation. Empirical experimental results on geoscience documents and benchmark datasets showed that GeoSegmenter could effectively recognise both geoscience terms and general terms.

Clinical characteristics of unruptured vertebral artery dissections presenting with headaches

International Nuclear Information System (INIS)

Nakamura, Homare; Mizuniwa, Yoshitaka; Kouno, Takao; Nakayama, Hirofumi; Furuya, Yu; Taguchi, Yoshio

2011-01-01

We reviewed 13 cases of patients with unruptured dissections of the vertebral artery who were treated at our hospital after presenting with headaches. We identified 13 patients who had headache alone at the time of onset and who were diagnosed as having vertebral artery dissection using three-dimensional CT, MRI, MR angiography (MRA), or angiography from November 2007 to October 2009. Primary radiographic investigations showed the 'pearl and string' sign in two cases, dilatation in eight, and the string sign alone in three cases. Following initial conservative treatment, 11 cases exhibited radiographic improvement, but two cases underwent surgical treatment because of progressive vertebral artery dissection. A definitive diagnosis was made using primary investigations in nine cases and dynamic changes on radiographic investigations in four cases. The headache was located posteriorly in all cases, but some patients had mild headaches. Clinicians need to be aware of the possibility of vertebral artery dissection even if the headache is mild at onset. Radiographic investigations are important for a definitive diagnosis and in deciding whether to intervene surgically. (author)

Assessment of radiological vertebral fractures in HIV-infected patients: clinical implications and predictive factors.

Science.gov (United States)

Gazzola, L; Savoldi, A; Bai, F; Magenta, A; Dziubak, M; Pietrogrande, L; Tagliabue, L; Del Sole, A; Bini, T; Marchetti, G; d'Arminio Monforte, A

2015-10-01

The aim of this study was to evaluate the clinical impact of including lateral spine X-ray in the screening of bone diseases in HIV-positive patients. A total of 194 HIV-positive patients underwent dual-energy X-ray absorptiometry (DEXA), lateral spine X-ray and bone biochemical analysis. Vertebral fractures were identified using a morphometric analysis of X-rays and classified using the semiquantitative scoring system of Genant et al. For each patient, a spine deformity index (SDI) score was calculated by summing the grades of vertebral deformities. Reductions in vertebral body height of > 25% were considered vertebral fractures, and those Risk factors associated with vertebral fractures were evaluated by univariate and multivariate analysis. Vertebral fractures were detected in 24 patients (12.4%) and vertebral deformities in 17 patients (8.7%); 153 patients (78.9%) did not show any vertebral deformity. Among patients with fractures, only two with SDI > 10 reported lumbar pain; the remaining were asymptomatic. Patients over 50 years old showed a higher prevalence of vertebral fracture [24.4% versus 11.8% in patients 41-50 years old (P = 0.05) and 1.9% in patients ≤ 40 years old (P = 0.04)]. No significant increase in the prevalence according to bone mineral density (BMD) reduction was observed, and 70% of fractures were diagnosed in nonosteoporotic patients. Older age [adjusted odds ratio 1.09; 95% confidence interval (CI) 1.03-1.13; P = 0.001] and steroid use (adjusted odds ratio 3.64; 95% CI 1.29-10.3; P = 0.01) were independently associated with vertebral fracture; no association was found with HIV- or highly active antiretroviral therapy (HAART)-related variables. A prevalence of vertebral fractures of 12.4% was observed in our HIV-positive cohort. Given that two-thirds of fractures occurred in nonosteoporotic patients, spine X-ray may be considered in patients at increased risk, irrespective of BMD; that is, in elderly patients

Learning about Vertebrate Limb Development

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Liang, Jennifer O.; Noll, Matthew; Olsen, Shayna

2014-01-01

We have developed an upper-level undergraduate laboratory exercise that enables students to replicate a key experiment in developmental biology. In this exercise, students have the opportunity to observe live chick embryos and stain the apical ectodermal ridge, a key tissue required for development of the vertebrate limb. Impressively, every…

Global patterns in threats to vertebrates by biological invasions

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Bellard, C.; Genovesi, P.; Jeschke, J. M.

2016-01-01

Biological invasions as drivers of biodiversity loss have recently been challenged. Fundamentally, we must know where species that are threatened by invasive alien species (IAS) live, and the degree to which they are threatened. We report the first study linking 1372 vertebrates threatened by more than 200 IAS from the completely revised Global Invasive Species Database. New maps of the vulnerability of threatened vertebrates to IAS permit assessments of whether IAS have a major influence on biodiversity, and if so, which taxonomic groups are threatened and where they are threatened. We found that centres of IAS-threatened vertebrates are concentrated in the Americas, India, Indonesia, Australia and New Zealand. The areas in which IAS-threatened species are located do not fully match the current hotspots of invasions, or the current hotspots of threatened species. The relative importance of biological invasions as drivers of biodiversity loss clearly varies across regions and taxa, and changes over time, with mammals from India, Indonesia, Australia and Europe are increasingly being threatened by IAS. The chytrid fungus primarily threatens amphibians, whereas invasive mammals primarily threaten other vertebrates. The differences in IAS threats between regions and taxa can help efficiently target IAS, which is essential for achieving the Strategic Plan 2020 of the Convention on Biological Diversity. PMID:26817767

The MRI appearances of early vertebral osteomyelitis and discitis

International Nuclear Information System (INIS)

Dunbar, J.A.T.; Sandoe, J.A.T.; Rao, A.S.; Crimmins, D.W.; Baig, W.; Rankine, J.J.

2010-01-01

Aim: To describe the magnetic resonance imaging (MRI) appearances in patients with a clinical history suggestive of vertebral osteomyelitis and discitis who underwent MRI very early in their clinical course. Materials and methods: A retrospective review of the database of spinal infections from a spinal microbiological liaison team was performed over a 2 year period to identify cases with clinical features suggestive of spinal infection and an MRI that did not show features typical of vertebral osteomyelitis and discitis. All patients had positive microbiology and a follow up MRI showing typical features of spinal infection. Results: In four cases the features typical of spinal infection were not evident at the initial MRI. In three cases there was very subtle endplate oedema associated with disc degeneration, which was interpreted as Modic type I degenerative endplate change. Intravenous antibiotic therapy was continued prior to repeat MRI examinations. The mean time to the repeat examination was 17 days with a range of 8-22 days. The second examinations clearly demonstrated vertebral osteomyelitis and discitis. Conclusion: Although MRI is the imaging method of choice for vertebral osteomyelitis and discitis in the early stages, it may show subtle, non-specific endplate subchondral changes; a repeat examination may be required to show the typical features.

Vertebral Osteophyte as Possible Etiology of Aortoenteric Fistula.

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Janko, Matthew; Ciocca, Rocco G; Hacker, Robert I

2018-05-01

Aortoenteric fistula (AEF) and aortoenteric erosion (AEE) are deadly and difficult to diagnose. We present here a case report of a patient with a delayed diagnosis of AEF whose preoperative imaging revealed a large vertebral osteophyte which likely directed the aortic impulse into the duodenum. We believe this is the first report documenting an anatomical explanation for AEF/AEE and conclude that the presence of vertebral osteophytes should be considered a risk factor when assessing preoperative likelihood of AEF/AEE. Copyright © 2018 Elsevier Inc. All rights reserved.

Laser Processing of Carbon Fiber Reinforced Plastics - Release of Carbon Fiber Segments During Short-pulsed Laser Processing of CFRP

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Walter, Juergen; Brodesser, Alexander; Hustedt, Michael; Bluemel, Sven; Jaeschke, Peter; Kaierle, Stefan

Cutting and ablation using short-pulsed laser radiation are promising technologies to produce or repair CFRP components with outstanding mechanical properties e.g. for automotive and aircraft industry. Using sophisticated laser processing strategies and avoiding excessive heating of the workpiece, a high processing quality can be achieved. However, the interaction of laser radiation and composite material causes a notable release of hazardous substances from the process zone, amongst others carbon fiber segments or fibrous particles. In this work, amounts and geometries of the released fiber segments are analyzed and discussed in terms of their hazardous potential. Moreover, it is investigated to what extent gaseous organic process emissions are adsorbed at the fiber segments, similar to an adsorption of volatile organic compounds at activated carbon, which is typically used as filter material.

The origin and diversification of the developmental mechanisms that pattern the vertebrate head skeleton.

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Square, Tyler; Jandzik, David; Romášek, Marek; Cerny, Robert; Medeiros, Daniel Meulemans

2017-07-15

The apparent evolvability of the vertebrate head skeleton has allowed a diverse array of shapes, sizes, and compositions of the head in order to better adapt species to their environments. This encompasses feeding, breathing, sensing, and communicating: the head skeleton somehow participated in the evolution of all these critical processes for the last 500 million years. Through evolution, present head diversity was made possible via developmental modifications to the first head skeletal genetic program. Understanding the development of the vertebrate common ancestor's head skeleton is thus an important step in identifying how different lineages have respectively achieved their many innovations in the head. To this end, cyclostomes (jawless vertebrates) are extremely useful, having diverged from jawed vertebrates approximately 400 million years ago, at the deepest node within living vertebrates. From this ancestral vantage point (that is, the node connecting cyclostomes and gnathostomes) we can best identify the earliest major differences in development between vertebrate classes, and start to address how these might translate onto morphology. In this review we survey what is currently known about the cell biology and gene expression during head development in modern vertebrates, allowing us to better characterize the developmental genetics driving head skeleton formation in the most recent common ancestor of all living vertebrates. By pairing this vertebrate composite with information from fossil chordates, we can also deduce how gene regulatory modules might have been arranged in the ancestral vertebrate head. Together, we can immediately begin to understand which aspects of head skeletal development are the most conserved, and which are divergent, informing us as to when the first differences appear during development, and thus which pathways or cell types might be involved in generating lineage specific shape and structure. Copyright © 2017 Elsevier Inc. All

Spatial coordination of compensatory eye movements in vertebrates: form and function.

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Graf, W

1988-01-01

The semicircular canals of the labyrinth of vertebrates provide one way of motion detection in three-dimensional space. The fully developed form of the vertebrate labyrinth consists of six semicircular canals, three on each side of the head, whose spatial arrangement (vertical canals are placed diagonally in the head, horizontal canals are oriented earth horizontally) follows three interconnected principles: 1) bilateral symmetry, 2) push-pull operational mode, and 3) mutual orthogonality. Other sensory and motor systems related to vestibular reflexes, such as the extraocular muscles or the "optokinetic" coordinate axes encoded in the activity of the visually driven cells of the accessory optic system, share the same geometrical framework. This framework is also reflected in the anatomical networks mediating compensatory eye movements, linking each of the semicircular canals to a particular set of extraocular muscles (so-called principal vestibuloocular reflex connections to yoke muscles). These classical vestibulo-oculomotor relationships have been verified at many levels of the vertebrate hierarchy, including lateral- and frontal-eyed animals. The particular spatial orientation of the semicircular canals requires further comment and phylogenetic evaluation. The spatial arrangement of the vertical canals is already present in fossil ostracoderms, and is also exemplified in lampreys, the modern forms of once abundant agnathan species that populated the Silurian and Devonian oceans. The lampreys and ostracoderms lack horizontal canals, which appear later in all descendent vertebrates. The fully developed vertebrate labyrinth with its six semicircular canals displays distinct differences that are obvious when comparing distant taxa (e.g. elasmobranchs versus other vertebrates). Whereas the common crus of the semicircular canals in teleosts through mammals is formed between the anterior and the posterior semicircular canal, it occurs between the anterior and the

Single-segment and double-segment INTACS for post-LASIK ectasia.

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Hassan Hashemi

2014-09-01

Full Text Available The objective of the present study was to compare single segment and double segment INTACS rings in the treatment of post-LASIK ectasia. In this interventional study, 26 eyes with post-LASIK ectasia were assessed. Ectasia was defined as progressive myopia regardless of astigmatism, along with topographic evidence of inferior steepening of the cornea after LASIK. We excluded those with a history of intraocular surgery, certain eye conditions, and immune disorders, as well as monocular, pregnant and lactating patients. A total of 11 eyes had double ring and 15 eyes had single ring implantation. Visual and refractive outcomes were compared with preoperative values based on the number of implanted INTACS rings. Pre and postoperative spherical equivalent were -3.92 and -2.29 diopter (P=0.007. The spherical equivalent decreased by 1 ± 3.2 diopter in the single-segment group and 2.56 ± 1.58 diopter in the double-segment group (P=0.165. Mean preoperative astigmatism was 2.38 ± 1.93 diopter which decreased to 2.14 ± 1.1 diopter after surgery (P=0.508; 0.87 ± 1.98 diopter decrease in the single-segment group and 0.67 ± 1.2 diopter increase in the double-segment group (P=0.025. Nineteen patients (75% gained one or two lines, and only three, who were all in the double-segment group, lost one or two lines of best corrected visual acuity. The spherical equivalent and vision significantly decreased in all patients. In these post-LASIK ectasia patients, the spherical equivalent was corrected better with two segments compared to single segment implantation; nonetheless, the level of astigmatism in the single-segment group was significantly better than that in the double-segment group.

Complex Vertebral Malformation (CVM) in an Italian Holstein calf

International Nuclear Information System (INIS)

Gentile, A.; Diana, A.; Testoni, S.; Olzi, E.

2004-01-01

Complex Vertebral Malformation, a congenital and lethal genetic defect of Holstein breed, has been recently observed in different Countries all over the world. In this paper the AA describe the clinical and radiological aspects of CVM in a two day old female calf. The disease was characterized by low body weight, symmetrical arthrogryposis and partial rotation of all legs and scoliosis. Calf was alert and showed physiological appetite, but was not able to maintain the quadrupedal stance. Radiographs of the vertebral column showed multiple vertebral anomalies, including hemivertebrae, fused and misshapen vertebrae and ribs and scoliosis, that affected mainly the caudal, cervical and thoracic regions. At necropsy, besides the skeleton anomalies, complex malformation of the heart was observed, which included atrial and interventricular defects and patent ductus arteriosus. This is the first case of CVM completely documented and genetically tested in Italy [it

Evolution of lung breathing from a lungless primitive vertebrate.

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Hoffman, M; Taylor, B E; Harris, M B

2016-04-01

Air breathing was critical to the terrestrial radiation and evolution of tetrapods and arose in fish. The vertebrate lung originated from a progenitor structure present in primitive boney fish. The origin of the neural substrates, which are sensitive to metabolically produced CO2 and which rhythmically activate respiratory muscles to match lung ventilation to metabolic demand, is enigmatic. We have found that a distinct periodic centrally generated rhythm, described as "cough" and occurring in lamprey in vivo and in vitro, is modulated by central sensitivity to CO2. This suggests that elements critical for the evolution of breathing in tetrapods, were present in the most basal vertebrate ancestors prior to the evolution of the lung. We propose that the evolution of breathing in all vertebrates occurred through exaptations derived from these critical basal elements. Copyright © 2015 Elsevier B.V. All rights reserved.

Inference of the ancestral vertebrate phenotype through vestiges of the whole-genome duplications.

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Onimaru, Koh; Kuraku, Shigehiro

2018-03-16

Inferring the phenotype of the last common ancestor of living vertebrates is a challenging problem because of several unresolvable factors. They include the lack of reliable out-groups of living vertebrates, poor information about less fossilizable organs and specialized traits of phylogenetically important species, such as lampreys and hagfishes (e.g. secondary loss of vertebrae in adult hagfishes). These factors undermine the reliability of ancestral reconstruction by traditional character mapping approaches based on maximum parsimony. In this article, we formulate an approach to hypothesizing ancestral vertebrate phenotypes using information from the phylogenetic and functional properties of genes duplicated by genome expansions in early vertebrate evolution. We named the conjecture as 'chronological reconstruction of ohnolog functions (CHROF)'. This CHROF conjecture raises the possibility that the last common ancestor of living vertebrates may have had more complex traits than currently thought.

Sensitivity and specificity of thallium-201 scintigraphy for the diagnosis of malignant vertebral fractures

International Nuclear Information System (INIS)

Thariat, Juliette; Toubeau, Michel; Ornetti, Paul; Coudert, Bruno; Berrielo-Riedinger, Alina; Fargeot, Pierre; Tavernier, Christian; Brunotte, Francois; Maillefert, Jean Francis

2004-01-01

Objective: To evaluate the accuracy of thallium-201 ( 201 TI) scintigraphy in distinguishing a benign from a malignant recent non-traumatic vertebral fracture. Methods: Study design--Single center, prospective study. Participants--Patients hospitalized for a recent non-traumatic vertebral fracture. Evaluation--Usual clinical, laboratory and radiological assessment; 201 TI vertebral scintigraphy: patients were injected with iv 3 mCi 201 TI. Early and delayed images of the fractured vertebra were obtained. Data analysis--(1) Two examinators, unaware of the other findings, rated the images as hyperfixation or not of the fractured vertebra; (2) the ratio (average count per pixel of the fractured vertebra/normal adjacent vertebrae) were calculated. The final diagnosis was established on the result of vertebral biopsy or on follow-up. Results: Twenty-one patients were included. The final diagnosis was a benign vertebral fracture in 14 patients and a malignant vertebral fracture in 7. The sensitivity, specificity, positive and negative predictive values for a malignant fracture on early 201 TI vertebral scintigraphy images were 28.6, 92.9, 66.6, and 72.2%, respectively, and on delayed images were 28.6, 100, 100, and 73.7%, respectively. The ratio of lesioned over normal tissue was not increased in malignant, compared with benign fractures. Conclusion: The weak sensitivity does not support the wide use of 201 TI bone scintigraphy to distinguish a benign from a malignant recent non traumatic vertebral fracture. However, the high specificity suggests that such evaluation might be proposed prior to vertebral biopsy in some difficult cases