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Sample records for gene-rich vertebrate regions

  1. Comparative analysis of chicken chromosome 28 provides new clues to the evolutionary fragility of gene-rich vertebrate regions

    PubMed Central

    Gordon, Laurie; Yang, Shan; Tran-Gyamfi, Mary; Baggott, Dan; Christensen, Mari; Hamilton, Aaron; Crooijmans, Richard; Groenen, Martien; Lucas, Susan; Ovcharenko, Ivan; Stubbs, Lisa

    2007-01-01

    The chicken genome draft sequence has provided a valuable resource for studies of an important agricultural and experimental model species and an important data set for comparative analysis. However, some of the most gene-rich segments are missing from chicken genome draft assemblies, limiting the analysis of a substantial number of genes and preventing a closer look at regions that are especially prone to syntenic rearrangements. To facilitate the functional and evolutionary analysis of one especially gene-rich, rearrangement-prone genomic region, we analyzed sequence from BAC clones spanning chicken microchromosome GGA28; as a complement we also analyzed a gene-sparse, stable region from GGA11. In these two regions we documented the conservation and lineage-specific gain and loss of protein-coding genes and precisely mapped the locations of 31 major human-chicken syntenic breakpoints. Altogether, we identified 72 lineage-specific genes, many of which are found at or near syntenic breaks, implicating evolutionary breakpoint regions as major sites of genetic innovation and change. Twenty-two of the 31 breakpoint regions have been reused repeatedly as rearrangement breakpoints in vertebrate evolution. Compared with stable GC-matched regions, GGA28 is highly enriched in CpG islands, as are break-prone intervals identified elsewhere in the chicken genome; evolutionary breakpoints are further enriched in GC content and CpG islands, highlighting a potential role for these features in genome instability. These data support the hypothesis that chromosome rearrangements have not occurred randomly over the course of vertebrate evolution but are focused preferentially within “fragile” regions with unusual DNA sequence characteristics. PMID:17921355

  2. Demarcating the gene-rich regions of the wheat genome

    PubMed Central

    Erayman, Mustafa; Sandhu, Devinder; Sidhu, Deepak; Dilbirligi, Muharrem; Baenziger, P. S.; Gill, Kulvinder S.

    2004-01-01

    By physically mapping 3025 loci including 252 phenotypically characterized genes and 17 quantitative trait loci (QTLs) relative to 334 deletion breakpoints, we localized the gene-containing fraction to 29% of the wheat genome present as 18 major and 30 minor gene-rich regions (GRRs). The GRRs varied both in gene number and density. The five largest GRRs physically spanning <3% of the genome contained 26% of the wheat genes. Approximate size of the GRRs ranged from 3 to 71 Mb. Recombination mainly occurred in the GRRs. Various GRRs varied as much as 128-fold for gene density and 140-fold for recombination rates. Except for a general suppression in 25–40% of the chromosomal region around centromeres, no correlation of recombination was observed with the gene density, the size, or chromosomal location of GRRs. More than 30% of the wheat genes are in recombination-poor regions thus are inaccessible to map-based cloning. PMID:15240829

  3. Comparative genomics of Lupinus angustifolius gene-rich regions: BAC library exploration, genetic mapping and cytogenetics

    PubMed Central

    2013-01-01

    Background The narrow-leafed lupin, Lupinus angustifolius L., is a grain legume species with a relatively compact genome. The species has 2n = 40 chromosomes and its genome size is 960 Mbp/1C. During the last decade, L. angustifolius genomic studies have achieved several milestones, such as molecular-marker development, linkage maps, and bacterial artificial chromosome (BAC) libraries. Here, these resources were integratively used to identify and sequence two gene-rich regions (GRRs) of the genome. Results The genome was screened with a probe representing the sequence of a microsatellite fragment length polymorphism (MFLP) marker linked to Phomopsis stem blight resistance. BAC clones selected by hybridization were subjected to restriction fingerprinting and contig assembly, and 232 BAC-ends were sequenced and annotated. BAC fluorescence in situ hybridization (BAC-FISH) identified eight single-locus clones. Based on physical mapping, cytogenetic localization, and BAC-end annotation, five clones were chosen for sequencing. Within the sequences of clones that hybridized in FISH to a single-locus, two large GRRs were identified. The GRRs showed strong and conserved synteny to Glycine max duplicated genome regions, illustrated by both identical gene order and parallel orientation. In contrast, in the clones with dispersed FISH signals, more than one-third of sequences were transposable elements. Sequenced, single-locus clones were used to develop 12 genetic markers, increasing the number of L. angustifolius chromosomes linked to appropriate linkage groups by five pairs. Conclusions In general, probes originating from MFLP sequences can assist genome screening and gene discovery. However, such probes are not useful for positional cloning, because they tend to hybridize to numerous loci. GRRs identified in L. angustifolius contained a low number of interspersed repeats and had a high level of synteny to the genome of the model legume G. max. Our results showed that

  4. The highly recombinogenic bz locus lies in an unusually gene-rich region of the maize genome.

    PubMed

    Fu, H; Park, W; Yan, X; Zheng, Z; Shen, B; Dooner, H K

    2001-07-17

    The bronze (bz) locus exhibits the highest rate of recombination of any gene in higher plants. To investigate the possible basis of this high rate of recombination, we have analyzed the physical organization of the region around the bz locus. Two adjacent bacterial artificial chromosome clones, comprising a 240-kb contig centered around the Bz-McC allele, were isolated, and 60 kb of contiguous DNA spanning the two bacterial artificial chromosome clones was sequenced. We find that the bz locus lies in an unusually gene-rich region of the maize genome. Ten genes, at least eight of which are shown to be transcribed, are contained in a 32-kb stretch of DNA that is uninterrupted by retrotransposons. We have isolated nearly full length cDNAs corresponding to the five proximal genes in the cluster. The average intertranscript distance between them is just 1 kb, revealing a surprisingly compact packaging of adjacent genes in this part of the genome. At least 11 small insertions, including several previously described miniature inverted repeat transposable elements, were detected in the introns and 3' untranslated regions of genes and between genes. The gene-rich region is flanked at the proximal and distal ends by retrotransposon blocks. Thus, the maize genome appears to have scattered regions of high gene density similar to those found in other plants. The unusually high rate of intragenic recombination seen in bz may be related to the very high gene density of the region.

  5. Gene-rich chromosomal regions are preferentially localized in the lamin B deficient nuclear blebs of atypical progeria cells.

    PubMed

    Bercht Pfleghaar, Katrin; Taimen, Pekka; Butin-Israeli, Veronika; Shimi, Takeshi; Langer-Freitag, Sabine; Markaki, Yolanda; Goldman, Anne E; Wehnert, Manfred; Goldman, Robert D

    2015-01-01

    More than 20 mutations in the gene encoding A-type lamins (LMNA) cause progeria, a rare premature aging disorder. The major pathognomonic hallmarks of progeria cells are seen as nuclear deformations or blebs that are related to the redistribution of A- and B-type lamins within the nuclear lamina. However, the functional significance of these progeria-associated blebs remains unknown. We have carried out an analysis of the structural and functional consequences of progeria-associated nuclear blebs in dermal fibroblasts from a progeria patient carrying a rare point mutation p.S143F (C428T) in lamin A/C. These blebs form microdomains that are devoid of major structural components of the nuclear envelope (NE)/lamina including B-type lamins and nuclear pore complexes (NPCs) and are enriched in A-type lamins. Using laser capture microdissection and comparative genomic hybridization (CGH) analyses, we show that, while these domains are devoid of centromeric heterochromatin and gene-poor regions of chromosomes, they are enriched in gene-rich chromosomal regions. The active form of RNA polymerase II is also greatly enriched in blebs as well as nascent RNA but the nuclear co-activator SKIP is significantly reduced in blebs compared to other transcription factors. Our results suggest that the p.S143F progeria mutation has a severe impact not only on the structure of the lamina but also on the organization of interphase chromatin domains and transcription. These structural defects are likely to contribute to gene expression changes reported in progeria and other types of laminopathies.

  6. Gene-rich chromosomal regions are preferentially localized in the lamin B deficient nuclear blebs of atypical progeria cells

    PubMed Central

    Bercht Pfleghaar, Katrin; Taimen, Pekka; Butin-Israeli, Veronika; Shimi, Takeshi; Langer-Freitag, Sabine; Markaki, Yolanda; Goldman, Anne E; Wehnert, Manfred; Goldman, Robert D

    2015-01-01

    More than 20 mutations in the gene encoding A-type lamins (LMNA) cause progeria, a rare premature aging disorder. The major pathognomonic hallmarks of progeria cells are seen as nuclear deformations or blebs that are related to the redistribution of A- and B-type lamins within the nuclear lamina. However, the functional significance of these progeria-associated blebs remains unknown. We have carried out an analysis of the structural and functional consequences of progeria-associated nuclear blebs in dermal fibroblasts from a progeria patient carrying a rare point mutation p.S143F (C428T) in lamin A/C. These blebs form microdomains that are devoid of major structural components of the nuclear envelope (NE)/lamina including B-type lamins and nuclear pore complexes (NPCs) and are enriched in A-type lamins. Using laser capture microdissection and comparative genomic hybridization (CGH) analyses, we show that, while these domains are devoid of centromeric heterochromatin and gene-poor regions of chromosomes, they are enriched in gene-rich chromosomal regions. The active form of RNA polymerase II is also greatly enriched in blebs as well as nascent RNA but the nuclear co-activator SKIP is significantly reduced in blebs compared to other transcription factors. Our results suggest that the p.S143F progeria mutation has a severe impact not only on the structure of the lamina but also on the organization of interphase chromatin domains and transcription. These structural defects are likely to contribute to gene expression changes reported in progeria and other types of laminopathies. PMID:25738644

  7. Fine structure mapping of a gene-rich region of wheat carrying Ph1, a suppressor of crossing over between homoeologous chromosomes

    PubMed Central

    Sidhu, Gaganpreet K.; Rustgi, Sachin; Shafqat, Mustafa N.; von Wettstein, Diter; Gill, Kulvinder S.

    2008-01-01

    The wheat gene-rich region (GRR) 5L0.5 contains many important genes, including Ph1, the principal regulator of chromosome pairing. Comparative marker analysis identified 32 genes for the GRR controlling important agronomic traits. Detailed characterization of this region was accomplished by first physically localizing 213 wheat group 5L-specific markers, using group 5 nulli-tetrasomics, three Ph1 gene deletion/insertion mutants, and nine terminal deletion lines with their breakpoints around the 5L0.5 region. The Ph1 gene was localized to a much smaller region within the GRR (Ph1 gene region). Of the 61 markers that mapped in the four subregions of the GRR, 9 mapped in the Ph1 gene region. High stringency sequence comparison (e < 1 ×10−25) of 157 group 5L-specific wheat ESTs identified orthologs for 80% sequences in rice and 71% in Arabidopsis. Rice orthologs were present on all rice chromosomes, although most (34%) were on rice chromosome 9 (R9). No single collinear region was identified in Arabidopsis even for a smaller region, such as the Ph1 gene region. Seven of the nine Ph1 gene region markers mapped within a 450-kb region on R9 with the same gene order. Detailed domain/motif analysis of the 91 putative genes present in the 450-kb region identified 26 candidates for the Ph1 gene, including genes involved in chromatin reorganization, microtubule attachment, acetyltransferases, methyltransferases, DNA binding, and meiosis/anther specific proteins. Five of these genes shared common domains/motifs with the meiosis specific genes Zip1, Scp1, Cor1, RAD50, RAD51, and RAD57. Wheat and Arabidopsis homologs for these rice genes were identified. PMID:18398005

  8. Remnants of the Legume Ancestral Genome Preserved in Gene-Rich Regions: Insights from Lupinus angustifolius Physical, Genetic, and Comparative Mapping.

    PubMed

    Książkiewicz, Michał; Zielezinski, Andrzej; Wyrwa, Katarzyna; Szczepaniak, Anna; Rychel, Sandra; Karlowski, Wojciech; Wolko, Bogdan; Naganowska, Barbara

    The narrow-leafed lupin (Lupinus angustifolius) was recently considered as a legume reference species. Genetic resources have been developed, including a draft genome sequence, linkage maps, nuclear DNA libraries, and cytogenetic chromosome-specific landmarks. Here, we used a complex approach, involving DNA fingerprinting, sequencing, genetic mapping, and molecular cytogenetics, to localize and analyze L. angustifolius gene-rich regions (GRRs). A L. angustifolius genomic bacterial artificial chromosome (BAC) library was screened with short sequence repeat (SSR)-based probes. Selected BACs were fingerprinted and assembled into contigs. BAC-end sequence (BES) annotation allowed us to choose clones for sequencing, targeting GRRs. Additionally, BESs were aligned to the scaffolds of the genome sequence. The genetic map was supplemented with 35 BES-derived markers, distributed in 14 linkage groups and tagging 37 scaffolds. The identified GRRs had an average gene density of 19.6 genes/100 kb and physical-to-genetic distance ratios of 11 to 109 kb/cM. Physical and genetic mapping was supported by multi-BAC-fluorescence in situ hybridization (FISH), and five new linkage groups were assigned to the chromosomes. Syntenic links to the genome sequences of five legume species (Medicago truncatula, Glycine max, Lotus japonicus, Phaseolus vulgaris, and Cajanus cajan) were identified. The comparative mapping of the two largest lupin GRRs provides novel evidence for ancient duplications in all of the studied species. These regions are conserved among representatives of the main clades of Papilionoideae. Furthermore, despite the complex evolution of legumes, some segments of the nuclear genome were not substantially modified and retained their quasi-ancestral structures. Cytogenetic markers anchored in these regions constitute a platform for heterologous mapping of legume genomes.

  9. The human homolog of a mouse-imprinted gene, Peg3, maps to a zinc finger gene-rich region of human chromosome 19q13.4.

    PubMed

    Kim, J; Ashworth, L; Branscomb, E; Stubbs, L

    1997-05-01

    Peg3 (paternally expressed gene 3) is the first imprinted gene detected in the proximal region of mouse chromosome 7. Because imprinting is a trait that is generally conserved among mammals, and imprinted domains generally encompass several adjacent genes, expression patterns and chromosomal environment of the human counterpart of Peg3 are of special interest. In this study we have localized human PEG3 approximately 2 Mb proximal of the telomere of chromosome 19q, within a region known to carry large numbers of tandemly clustered Krüppel-type zinc finger-containing (ZNF) genes. Peg3 also encodes a Krüppel-type ZNF protein but one that is distinguished from other ZNF gene products by the fact that it carries two novel proline-rich motifs. Comparison between mouse Peg3 and partial human PEG3 gene sequences revealed a high level of conservation between the two species, despite the fact that one of the two proline-rich repeats is absent from the human gene. Our data demonstrate that the human gene is expressed at highest levels in ovary and placenta; mouse Peg3, by contrast, is transcribed at highest levels in the adult brain. These comparative mapping, sequencing, and expression data provide the first clues to the potential activities of PEG3, and generate new tools to aid in the analysis of structure and function of a potentially new imprinted domain located in human chromosome 19q13.4 and mouse chromosome 7.

  10. Evolution of the Beckwith-Wiedemann syndrome region in vertebrates.

    PubMed

    Paulsen, Martina; Khare, Tarang; Burgard, Christopher; Tierling, Sascha; Walter, Jörn

    2005-01-01

    In the animal kingdom, genomic imprinting appears to be restricted to mammals. It remains an open question how structural features for imprinting evolved in mammalian genomes. The clustering of genes around imprinting control centers (ICs) is regarded as a hallmark for the coordinated imprinted regulation. Hence imprinted clusters might be structurally distinct between mammals and nonimprinted vertebrates. To address this question we compared the organization of the Beckwith Wiedemann syndrome (BWS) gene cluster in mammals, chicken, Fugu (pufferfish), and zebrafish. Our analysis shows that gene synteny is apparently well conserved between mammals and birds, and is detectable but less pronounced in fish. Hence, clustering apparently evolved during vertebrate radiation and involved two major duplication events that took place before the separation of the fish and mammalian lineages. A cross-species analysis of imprinting center regions showed that some structural features can already be recognized in nonimprinted amniotes in one of the imprinting centers (IC2). In contrast, the imprinting center IC1 is absent in chicken. This suggests a progressive and stepwise evolution of imprinting control elements. In line with that, imprinting centers in mammals apparently exhibit a high degree of structural and sequence variation despite conserved epigenetic marking.

  11. Molecular regionalization of the developing amphioxus neural tube challenges major partitions of the vertebrate brain

    PubMed Central

    Albuixech-Crespo, Beatriz; Maeso, Ignacio; Sánchez-Arrones, Luisa; Moreno-Bravo, Juan Antonio; Somorjai, Ildiko; Pascual-Anaya, Juan; Puelles, Eduardo; Bovolenta, Paola; Garcia-Fernàndez, Jordi; Puelles, Luis; Ferran, José Luis

    2017-01-01

    All vertebrate brains develop following a common Bauplan defined by anteroposterior (AP) and dorsoventral (DV) subdivisions, characterized by largely conserved differential expression of gene markers. However, it is still unclear how this Bauplan originated during evolution. We studied the relative expression of 48 genes with key roles in vertebrate neural patterning in a representative amphioxus embryonic stage. Unlike nonchordates, amphioxus develops its central nervous system (CNS) from a neural plate that is homologous to that of vertebrates, allowing direct topological comparisons. The resulting genoarchitectonic model revealed that the amphioxus incipient neural tube is unexpectedly complex, consisting of several AP and DV molecular partitions. Strikingly, comparison with vertebrates indicates that the vertebrate thalamus, pretectum, and midbrain domains jointly correspond to a single amphioxus region, which we termed Di-Mesencephalic primordium (DiMes). This suggests that these domains have a common developmental and evolutionary origin, as supported by functional experiments manipulating secondary organizers in zebrafish and mice. PMID:28422959

  12. Molecular regionalization of the developing amphioxus neural tube challenges major partitions of the vertebrate brain.

    PubMed

    Albuixech-Crespo, Beatriz; López-Blanch, Laura; Burguera, Demian; Maeso, Ignacio; Sánchez-Arrones, Luisa; Moreno-Bravo, Juan Antonio; Somorjai, Ildiko; Pascual-Anaya, Juan; Puelles, Eduardo; Bovolenta, Paola; Garcia-Fernàndez, Jordi; Puelles, Luis; Irimia, Manuel; Ferran, José Luis

    2017-04-01

    All vertebrate brains develop following a common Bauplan defined by anteroposterior (AP) and dorsoventral (DV) subdivisions, characterized by largely conserved differential expression of gene markers. However, it is still unclear how this Bauplan originated during evolution. We studied the relative expression of 48 genes with key roles in vertebrate neural patterning in a representative amphioxus embryonic stage. Unlike nonchordates, amphioxus develops its central nervous system (CNS) from a neural plate that is homologous to that of vertebrates, allowing direct topological comparisons. The resulting genoarchitectonic model revealed that the amphioxus incipient neural tube is unexpectedly complex, consisting of several AP and DV molecular partitions. Strikingly, comparison with vertebrates indicates that the vertebrate thalamus, pretectum, and midbrain domains jointly correspond to a single amphioxus region, which we termed Di-Mesencephalic primordium (DiMes). This suggests that these domains have a common developmental and evolutionary origin, as supported by functional experiments manipulating secondary organizers in zebrafish and mice.

  13. ECRbase: Database of Evolutionary Conserved Regions, Promoters, and Transcription Factor Binding Sites in Vertebrate Genomes

    DOE Data Explorer

    Loots, Gabriela G. [LLNL; Ovcharenko, I. [LLNL

    Evolutionary conservation of DNA sequences provides a tool for the identification of functional elements in genomes. This database of evolutionary conserved regions (ECRs) in vertebrate genomes features a database of syntenic blocks that recapitulate the evolution of rearrangements in vertebrates and a comprehensive collection of promoters in all vertebrate genomes generated using multiple sources of gene annotation. The database also contains a collection of annotated transcription factor binding sites (TFBSs) in evolutionary conserved and promoter elements. ECRbase currently includes human, rhesus macaque, dog, opossum, rat, mouse, chicken, frog, zebrafish, and fugu genomes. (taken from paper in Journal: Bioinformatics, November 7, 2006, pp. 122-124

  14. Regional variations in microstructural properties of vertebral trabeculae with structural groups.

    PubMed

    Gong, He; Zhang, Ming; Qin, Ling; Lee, Kenneth Ka Ho; Guo, Xia; Shi, San-Qiang

    2006-01-01

    Micro-computed tomography (CT) scanning to investigate three-dimensional microstructural properties of L4 vertebral bodies. To identify the regional variations in the three-dimensional microstructural properties of vertebral cancellous bones with respect to structural types for the prediction of related regional fracture risks. The literature contains no reports on regional variations in morphologic properties of vertebral trabeculae with microstructural types, which may shed light on the patterns of osteoporotic fractures. Ninety cubic cancellous specimens were obtained from 6 normal L4 vertebral bodies of 6 male donors 62 to 70 years of age and were scanned using a high-resolution micro-CT system. These specimens were further divided into two groups according to the average structure model index (SMI) of the 15 trabecular specimens in each vertebral body. Adjustment for age differences was done for the microstructural parameters, i.e.-, bone volume fraction, trabecular number, trabecular thickness, structure model index, degree of architectural anisotropy, and connectivity density, to allow investigation on the regional variations in different transverse layers and vertical columns independent of age. Trabecular specimens with lower mass were liable to form high-SMI group and the differences in all parameters reached significance level either between columns or between layers from two groups. The anterior column in the high-SMI group is more susceptible to vertebral body wedge fracture; and in the low-SMI group, off-axis bone damage is most harmful to the central column of vertebral trabeculae. The data obtained may help to identify the most critical locations of fracture risks at an early stage and provide a microstructural basis for the repair and clinical treatment of vertebral fractures.

  15. ECRbase: Database of Evolutionary Conserved Regions, Promoters, and Transcription Factor Binding Sites in Vertebrate Genomes

    SciTech Connect

    Loots, G; Ovcharenko, I

    2006-08-08

    Evolutionary conservation of DNA sequences provides a tool for the identification of functional elements in genomes. We have created a database of evolutionary conserved regions (ECRs) in vertebrate genomes entitled ECRbase that is constructed from a collection of pairwise vertebrate genome alignments produced by the ECR Browser database. ECRbase features a database of syntenic blocks that recapitulate the evolution of rearrangements in vertebrates and a collection of promoters in all vertebrate genomes presented in the database. The database also contains a collection of annotated transcription factor binding sites (TFBS) in all ECRs and promoter elements. ECRbase currently includes human, rhesus macaque, dog, opossum, rat, mouse, chicken, frog, zebrafish, and two pufferfish genomes. It is freely accessible at http://ECRbase.dcode.org.

  16. Regional variation in morphology of vertebral centra and intervertebral joints in striped bass, Morone saxatilis.

    PubMed

    Nowroozi, B N; Harper, C J; De Kegel, B; Adriaens, D; Brainerd, E L

    2012-04-01

    The vertebral column of fishes has traditionally been divided into just two distinct regions, abdominal and caudal. Recently, however, developmental, morphological, and mechanical investigations have brought this traditional regionalization scheme into question. Alternative regionalization schema advocate the division of the abdominal vertebrae into cervical, abdominal, and in some cases, transitional regions. Here, we investigate regional variation at the level of the vertebrae and intervertebral joint (IVJ) tissues in the striped bass, Morone saxatilis. We use gross dissection, histology, and polarized light imaging to quantify vertebral height, width, length, IVJ length, IVJ tissue volume and cross-sectional area, and vertical septum fiber populations, and angles of insertion. Our results reveal regional differences between the first four (most rostral) abdominal vertebrae and IVJs and the next six abdominal vertebrae and IVJs, supporting the recognition of a distinct cervical region. We found significant variation in vertebral length, width, and height from cranial to caudal. In addition, we see a significant decline in the volume of notochordal cells and the cross-sectional area of the fibrous sheath from cranial to caudal. Further, polarized light imaging revealed four distinct fiber populations within the vertical septum in the cervical and abdominal regions in contrast with just one fiber population found in the caudal region. Measurement of the insertion angles of these fiber populations revealed significant differences between the cervical and abdominal regions. Differences in vertebral, IVJ, and vertical septum morphology all predict greater range of motion and decreased stiffness in the caudal region of the fish compared with the cervical and abdominal regions.

  17. Transmission of weight through the lower thoracic and lumbar regions of the vertebral column in man.

    PubMed Central

    Pal, G P; Routal, R V

    1987-01-01

    This study is an attempt to investigate the role of the neural arches in transmission of weight in the lower thoracic and the lumbar regions of the vertebral column. Based on simple mechanical principles of weight transmission, various parameters were chosen for measurements at each vertebral level. In 44 adult male dry vertebral columns measurements were made from T5 to L5 levels. The area of the inferior surface of the body at each vertebral level was compared with the area of the inferior articular facet, the cross sectional area of the laminae (lamina index), the pedicle index and the arch index. The inclination of the pedicles in relation to the body was also measured at each level. On the basis of the above measurements it was deduced that the compression force in the lower thoracic and lumbar regions is transmitted through two parallel columns, one anterior (formed by bodies and intervertebral discs) and one posterior (formed by successive articulations of laminae with each other at their articular facets). This study suggests that a considerable part of the weight of the upper limbs and the thoracic cage is transmitted through the ribs to the posterior column (laminae) through the costo-transverse articulations and ligaments. Because of the inclined position of the fifth lumbar vertebra, a significant part of the compressive force from the body is transmitted to the laminae in spite of the anterior inclination of the pedicles at this level. Because of the anterior concavity of the spine in the thoracic region, weight is transferred from the posterior to the anterior column through the inclined pedicles and in the lumbar region, where the concavity is posterior, a part of the compressive force of the anterior column is transmitted to the posterior. Thus, the compressive force in the curvilinear thoracolumbar column tends to deviate towards the line of gravity. The implications of these findings in relation to clinico-pathological disorders of the spine are

  18. Regional Variations in Shear Strength and Density of the Human Thoracic Vertebral Endplate and Trabecular Bone

    PubMed Central

    Jauregui, Julio J.; Cornish, Nathan; Jason-Rousseau, Rebecca; Chatterjee, Dipal; Feuer, Gavriel; Hayes, Westley; Kapadia, Bhaveen H.; Carter, John N.; Yoshihara, Hiroyuki; Saha, Subrata

    2017-01-01

    Background Previous studies investigated the overall mechanical strength of the vertebral body; however, limited information is available on the biomechanical properties of different regions within the vertebral endplate and cancellous bone. In addition, the correlation between mechanical strength and various density measurements has not been studied yet. Methods Thoracic (T10) vertebrae were harvested from fifteen human cadaveric spines (average age: 77 years old). Twelve cylindrical cores of 7.2 mm (diameter) by 3.2 mm (height) were prepared from each vertebral body. Shear was produced using a stainless steel tubular blade and measured with a load cell from a mechanical testing machine. Optical and bulk densities were calculated before mechanical testing. Apparent, material, and ash densities were measured after testing. Results Material density and shear strength increased from anterior to lateral regions of both endplate and cancellous bone. Endplate shear strength was significantly lower in the anterior (0.52 ± 0.08 MPa) than in the lateral region (2.72 ± 0.59 MPa) (p=0.017). Trabecular bone maximum load carrying capacity was 5 times higher in the lateral (12 ± 2.74 N) (p=0.09) and 4.5 times higher in the central (10 ± 2.24 N) (p=0.2) than in the anterior (2 ± 0.60 N) regions. Mechanical strength positively correlated with ash density, and even moreso with material density. Conclusion Shear strength was the lowest at the anterior region and highest at the lateral region for both endplate and cancellous bone. Material density had the best correlation with mechanical strength. Newer spinal implants could optimize the loading in the lateral aspects of both endplate and cancellous bone to reduce the likelihood of screw loosening and the subsidence of disc replacement devices. This study was reviewed by the SUNY Downstate Medical Center IRB Committee; IRB#: 533603-2. PMID:28377865

  19. Condensin I associates with structural and gene regulatory regions in vertebrate chromosomes

    PubMed Central

    Kim, Ji Hun; Zhang, Tao; Wong, Nicholas C; Davidson, Nadia; Maksimovic, Jovana; Oshlack, Alicia; Earnshaw, William C; Kalitsis, Paul; Hudson, Damien F

    2014-01-01

    The condensin complex is essential for correct packaging and segregation of chromosomes during mitosis and meiosis in all eukaryotes. To date, the genome wide location and the nature of condensin binding sites has remained elusive in vertebrates. Here we report the genome wide map of condensin I in chicken DT40 cells. Unexpectedly, we find condensin I binds predominately to promoter sequences in mitotic cells. We also find a striking enrichment at both centromeres and telomeres, highlighting the importance of the complex in chromosome segregation. Taken together, the results show condensin I is largely absent from heterochromatic regions. This map of the condensin I binding sites on the chicken genome reveals that patterns of condensin distribution on chromosomes are conserved from prokaryotes, through yeasts to vertebrates. Thus in three kingdoms of life, condensin is enriched on promoters of actively transcribed genes and at loci important for chromosome segregation. PMID:24088984

  20. Genetic analysis of vertebral regionalization and number in medaka (Oryzias latipes) inbred lines.

    PubMed

    Kimura, Tetsuaki; Shinya, Minori; Naruse, Kiyosi

    2012-11-01

    Vertebral number is the most variable trait among vertebrates. In addition to the vertebral number, the ratio of abdominal to caudal vertebrae is a variable trait. The vertebral number and the ratio of abdominal to caudal vertebrae contribute to vertebrate diversity. It is very interesting to know how to determine the vertebral number and the ratio of abdominal to caudal vertebrae. In this study, we identify differences in the vertebral number and the ratio of abdominal vertebrae to vertebral number between two inbred lines of medaka, namely, Hd-rRII1 and Kaga. To identify the genetic factor of those differences, we performed quantitative trait locus (QTL) analysis for vertebral number and the ratio of abdominal vertebrae to vertebral number using 200 F(2) fish. Our results show a suggestive QTL of the ratio of abdominal vertebrae to vertebral number on chromosome 15, and five QTL of vertebral number on chromosomes 1, 10, 11, 17, and 23. The QTL on chromosome 15 contains hoxDb cluster genes. The QTL of vertebral number include some genes related to the segmentation clock and axial elongation. In addition, we show that the difference in vertebral number between two inbred lines is derived from differences in the anteroposterior length of somites. Our results emphasize that the developmental process should be considered in genetic analyses for vertebral number.

  1. Regional variation in the mechanical properties of the vertebral column during lateral bending in Morone saxatilis.

    PubMed

    Nowroozi, B N; Brainerd, E L

    2012-10-07

    Unlike mammalian, disc-shaped intervertebral joints (IVJs), the IVJs in fishes are biconid structures, filled with fluid and thought to act as hydrostatic hinge joints during swimming. However, it remains unclear which IVJ structures are dominant in mechanical resistance to forces in fishes, and whether variation in these tissues might impact the function of the vertebral column along its length. Here, we measured the dynamic mechanical behaviour of IVJs from striped bass, Morone saxatilis. During lateral bending, angular stiffness was significantly lower in the caudal and cervical regions, relative to the abdominal region. The neutral zone, defined as the range of motion (ROM) at bending moments less than 0.001 Nm, was longer in the caudal relative to the abdominal IVJs. Hysteresis was 30-40% in all regions, suggesting that IVJs may play a role in energy dissipation during swimming. Cutting the vertical septum had no statistically significant effect, but cutting the encapsulating tissues caused a sharp decline in angular stiffness and a substantial increase in ROM and hysteresis. We conclude that stiffness decreases and ROM increases from cranial to caudal in striped bass, and that the encapsulating tissues play a prominent role in mechanical variation along the length of the vertebral column.

  2. Regional variation in the mechanical properties of the vertebral column during lateral bending in Morone saxatilis

    PubMed Central

    Nowroozi, B. N.; Brainerd, E. L.

    2012-01-01

    Unlike mammalian, disc-shaped intervertebral joints (IVJs), the IVJs in fishes are biconid structures, filled with fluid and thought to act as hydrostatic hinge joints during swimming. However, it remains unclear which IVJ structures are dominant in mechanical resistance to forces in fishes, and whether variation in these tissues might impact the function of the vertebral column along its length. Here, we measured the dynamic mechanical behaviour of IVJs from striped bass, Morone saxatilis. During lateral bending, angular stiffness was significantly lower in the caudal and cervical regions, relative to the abdominal region. The neutral zone, defined as the range of motion (ROM) at bending moments less than 0.001 Nm, was longer in the caudal relative to the abdominal IVJs. Hysteresis was 30–40% in all regions, suggesting that IVJs may play a role in energy dissipation during swimming. Cutting the vertical septum had no statistically significant effect, but cutting the encapsulating tissues caused a sharp decline in angular stiffness and a substantial increase in ROM and hysteresis. We conclude that stiffness decreases and ROM increases from cranial to caudal in striped bass, and that the encapsulating tissues play a prominent role in mechanical variation along the length of the vertebral column. PMID:22552920

  3. Dietary intervention impact on gut microbial gene richness.

    PubMed

    Cotillard, Aurélie; Kennedy, Sean P; Kong, Ling Chun; Prifti, Edi; Pons, Nicolas; Le Chatelier, Emmanuelle; Almeida, Mathieu; Quinquis, Benoit; Levenez, Florence; Galleron, Nathalie; Gougis, Sophie; Rizkalla, Salwa; Batto, Jean-Michel; Renault, Pierre; Doré, Joel; Zucker, Jean-Daniel; Clément, Karine; Ehrlich, Stanislav Dusko

    2013-08-29

    Complex gene-environment interactions are considered important in the development of obesity. The composition of the gut microbiota can determine the efficacy of energy harvest from food and changes in dietary composition have been associated with changes in the composition of gut microbial populations. The capacity to explore microbiota composition was markedly improved by the development of metagenomic approaches, which have already allowed production of the first human gut microbial gene catalogue and stratifying individuals by their gut genomic profile into different enterotypes, but the analyses were carried out mainly in non-intervention settings. To investigate the temporal relationships between food intake, gut microbiota and metabolic and inflammatory phenotypes, we conducted diet-induced weight-loss and weight-stabilization interventions in a study sample of 38 obese and 11 overweight individuals. Here we report that individuals with reduced microbial gene richness (40%) present more pronounced dys-metabolism and low-grade inflammation, as observed concomitantly in the accompanying paper. Dietary intervention improves low gene richness and clinical phenotypes, but seems to be less efficient for inflammation variables in individuals with lower gene richness. Low gene richness may therefore have predictive potential for the efficacy of intervention.

  4. The human vertebral column at the end of the embryonic period proper. 2. The occipitocervical region.

    PubMed Central

    O'Rahilly, R; Müller, F; Meyer, D B

    1983-01-01

    The present investigation of the cervical region of the vertebral column at eight post-ovulatory weeks is the first such study based on precise reconstructions of staged embryos. At the end of the embryonic period proper, a typical vertebra is a U-shaped piece of cartilage characterized by spina bifida occulta. The notochord ascends through the centra and leaves the dens to enter the basal plate of the skull. The median column of the axis comprises three parts (designated X, Y, Z) which persist well into the fetal period. They are related to the first, second and third cervical nerves, respectively. Part X may project into the foramen magnum and form an occipito-axial joint. Part Z appears to be the centrum of the axis. The articular columns of the cervical vertebrae are twofold, as in the adult: an anterior (atlanto-occipital and atlanto-axial) and a posterior (from the lower aspect of the axis downwards). Alar and transverse ligaments are present. Cavitation is not found in the embryonic period in either the atlanto-occipital or zygapophysial joints, and is generally not present in the median atlanto-axial joint either. Most of the transverse processes exhibit anterior and posterior tubercles. An 'intertubercular lamella' may or may not be present, i.e. the foramina transversaria are being formed around the vertebral artery. The spinal ganglia are generally partly in the vertebral canal and partly on the neural arches, medial to the articular processes. During the fetal period, the articular processes shift to a coronal position and this alteration appears to be associated with a corresponding change in the location of the spinal ganglia. Images Fig. 4 Fig. 7 PMID:6833119

  5. Evolution of the vertebrate genome as reflected in paralogous chromosomal regions in man and the house mouse

    SciTech Connect

    Lundin, L.G. )

    1993-04-01

    Gene constellations on several human chromosomes are interpreted as indications of large regional duplications that took place during evolution of the vertebrate genome. Four groups of paralogous chromosomal regions in man and the house mouse are suggested and are believed to be conserved remnants of the two or three rounds of tetraploidization that are likely to have occurred during evolution of the vertebrates. The phenomenon of differential silencing of genes is described. The importance of conservation of linkage of particular genes is discussed in relation to genetic regulation and cell differentiation. 120 refs., 5 tabs.

  6. Complete structure and organization of immunoglobulin heavy chain constant region genes in a phylogenetically primitive vertebrate.

    PubMed Central

    Kokubu, F; Hinds, K; Litman, R; Shamblott, M J; Litman, G W

    1988-01-01

    Immunoglobulin (Ig) gene organization in Heterodontus francisci (horned shark), a phylogenetically primitive vertebrate, is unique. Homologous Ig heavy chain variable (VH) and constant region (CH) specific probes were used to screen a spleen cDNA library constructed in lambda gt11. Both secretory (SEC) and transmembrane (TM) cDNA clones were recovered; the latter were identified by a negative selection strategy. The complete sequence of the CH portion of a Heterodontus genomic DNA-lambda clone also was determined. The sequences of the individual CH genes differ from each other in all exons. When compared to mammalian prototypes, similarities in exon and intron organization as well as conservation of sequences involved with differential splicing of SEC and TM mRNA indicate that Heterodontus heavy chain genes are of the mu type, although intron lengths are uniformly longer in Heterodontus. Heterodontus genes are not associated, however, with the family of DNA sequences that have been implicated in heavy chain class switching in mammals. Spleen cDNA library screening and RNA blot analyses indicate that mRNAs encoding TM Ig are exceedingly rare. The relationship between this quantitative difference and the distribution of polyadenylation signal sequences suggests that regulation of Ig gene expression in Heterodontus may be highly dependent on position effects. Images PMID:3138109

  7. Complete structure and organization of immunoglobulin heavy chain constant region genes in a phylogenetically primitive vertebrate.

    PubMed

    Kokubu, F; Hinds, K; Litman, R; Shamblott, M J; Litman, G W

    1988-07-01

    Immunoglobulin (Ig) gene organization in Heterodontus francisci (horned shark), a phylogenetically primitive vertebrate, is unique. Homologous Ig heavy chain variable (VH) and constant region (CH) specific probes were used to screen a spleen cDNA library constructed in lambda gt11. Both secretory (SEC) and transmembrane (TM) cDNA clones were recovered; the latter were identified by a negative selection strategy. The complete sequence of the CH portion of a Heterodontus genomic DNA-lambda clone also was determined. The sequences of the individual CH genes differ from each other in all exons. When compared to mammalian prototypes, similarities in exon and intron organization as well as conservation of sequences involved with differential splicing of SEC and TM mRNA indicate that Heterodontus heavy chain genes are of the mu type, although intron lengths are uniformly longer in Heterodontus. Heterodontus genes are not associated, however, with the family of DNA sequences that have been implicated in heavy chain class switching in mammals. Spleen cDNA library screening and RNA blot analyses indicate that mRNAs encoding TM Ig are exceedingly rare. The relationship between this quantitative difference and the distribution of polyadenylation signal sequences suggests that regulation of Ig gene expression in Heterodontus may be highly dependent on position effects.

  8. Effects of vertebral mobilization and manipulation on kinematics of the thoracolumbar region.

    PubMed

    Haussler, Kevin K; Hill, Ashley E; Puttlitz, Christian M; McIlwraith, C Wayne

    2007-05-01

    To measure passive spinal movements induced during dorsoventral mobilization and evaluate effects of induced pain and spinal manipulative therapy (SMT) on passive vertebral mobility in standing horses. 10 healthy adult horses. Baseline vertical displacements, applied force, stiffness, and frequency of the oscillations were measured during dorsoventral spinal mobilization at 5 thoracolumbar intervertebral sites. As a model for back pain, fixation pins were temporarily implanted into the dorsal spinous processes of adjacent vertebrae at 2 of the intervertebral sites. Vertebral variables were recorded again after pin placement and treadmill locomotion. In a randomized crossover study, horses were allocated to control and treatment interventions, separated by a 7-day washout period. The SMT consisted of high-velocity, low-amplitude thrusts applied to the 3 non-pin-placement sites. Control horses received no treatment. The amplitudes of vertical displacement increased from cranial to caudal in the thoracolumbar portion of the vertebral column. Pin implantation caused no immediate changes at adjacent intervertebral sites, but treadmill exercise caused reductions in most variables. The SMT induced a 15% increase in displacement and a 20% increase in applied force, compared with control measurements. The passive vertical mobility of the trunk varied from cranial to caudal. At most sites, SMT increased the amplitudes of dorsoventral displacement and applied force, indicative of increased vertebral flexibility and increased tolerance to pressure in the thoracolumbar portion of the vertebral column.

  9. V. Terrestrial vertebrates

    Treesearch

    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...

  10. Vertebrate fossils and trace fossils in Upper Jurassic-Lower cretaceous red beds in the Atacama region, Chile

    NASA Astrophysics Data System (ADS)

    Bell, C. M.; Suárez, M.

    Pterosaur, dinosaur, and crocodile bones are recorded here for the first time in Upper Jurassic-Lower Cretaceous red beds in the Atacama region east of Copiapó, Chile. Trace fossils produced by vertebrate animals include the footprints of theropod dinosaurs and the depressions of sandstone laminae interpreted as burrows and foot impressions. The fossils occur in the 1500-meter-thick Quebrada Monardes Formation, which consists predominantly of the aeolian and alluvial deposits of a semi-arid terrestrial environment. Vertebrate fossils are very rare in Chile. Dinosaur bones and footprints have previously been recorded at only seven locations, and pterosaur remains at only one location. The newly discovered dinosaur bones are the oldest to be described in Chile.

  11. HNK-1 immunoreactivity during early morphogenesis of the head region in a nonmodel vertebrate, crocodile embryo.

    PubMed

    Kundrát, Martin

    2008-11-01

    The present study examines HNK-1 immunoidentification of a population of the neural crest (NC) during early head morphogenesis in the nonmodel vertebrate, the crocodile (Crocodylus niloticus) embryos. Although HNK-1 is not an exclusive NC marker among vertebrates, temporospatial immunoreactive patterns found in the crocodile are almost consistent with NC patterns derived from gene expression studies known in birds (the closest living relatives of crocodiles) and mammals. In contrast to birds, the HNK-1 epitope is immunoreactive in NC cells at the neural fold level in crocodile embryos and therefore provides sufficient base to assess early migratory events of the cephalic NC. I found that crocodile NC forms three classic migratory pathways in the head: mandibular, hyoid, and branchial. Further, I demonstrate that, besides this classic phenotype, there is also a forebrain-derived migratory population, which consolidates into a premandibular stream in the crocodile. In contrast to the closely related chick model, crocodilian premandibular and mandibular NC cells arise from the open neural tube suggesting that species-specific heterochronic behavior of NC may be involved in the formation of different vertebrate facial phenotypes.

  12. HNK-1 immunoreactivity during early morphogenesis of the head region in a nonmodel vertebrate, crocodile embryo

    NASA Astrophysics Data System (ADS)

    Kundrát, Martin

    2008-11-01

    The present study examines HNK-1 immunoidentification of a population of the neural crest (NC) during early head morphogenesis in the nonmodel vertebrate, the crocodile ( Crocodylus niloticus) embryos. Although HNK-1 is not an exclusive NC marker among vertebrates, temporospatial immunoreactive patterns found in the crocodile are almost consistent with NC patterns derived from gene expression studies known in birds (the closest living relatives of crocodiles) and mammals. In contrast to birds, the HNK-1 epitope is immunoreactive in NC cells at the neural fold level in crocodile embryos and therefore provides sufficient base to assess early migratory events of the cephalic NC. I found that crocodile NC forms three classic migratory pathways in the head: mandibular, hyoid, and branchial. Further, I demonstrate that, besides this classic phenotype, there is also a forebrain-derived migratory population, which consolidates into a premandibular stream in the crocodile. In contrast to the closely related chick model, crocodilian premandibular and mandibular NC cells arise from the open neural tube suggesting that species-specific heterochronic behavior of NC may be involved in the formation of different vertebrate facial phenotypes.

  13. Extensive families of constant region genes in a phylogenetically primitive vertebrate indicate an additional level of immunoglobulin complexity.

    PubMed Central

    Kokubu, F; Hinds, K; Litman, R; Shamblott, M J; Litman, G W

    1987-01-01

    A homologous probe for the constant region of the Heterodontus francisci (horned shark) immunoglobulin heavy chain was used to screen a genomic DNA library constructed in bacteriophage lambda, and a large number of independent clones were recovered. Their hybridization patterns with segment-specific probes are consistent with the close linkage of heavy-chain constant (CH), joining (JH), and variable (VH) gene segments. Differences in the nucleotide sequences of the first CH exon of five genes primarily are localized to 5' positions; extended regions of sequence identity are noted at 3' positions. The predicted amino acid sequences of each gene are different and are related distantly to the corresponding regions of higher vertebrate immunoglobulins. Gene-specific oligodeoxynucleotide probes were used to establish that at least three of the five genes are transcriptionally active. Quantitative gene titration data are consistent with the large numbers of genes suggested by the library screening analyses. In this representative early vertebrate, it appears that (VH-diversity-JH) segments are associated with individual constant region genes that can differ at the predicted protein level. Images PMID:3475706

  14. Expression of growth differentiation factor 6 in the human developing fetal spine retreats from vertebral ossifying regions and is restricted to cartilaginous tissues.

    PubMed

    Wei, Aiqun; Shen, Bojiang; Williams, Lisa A; Bhargav, Divya; Gulati, Twishi; Fang, Zhimin; Pathmanandavel, Sarennya; Diwan, Ashish D

    2016-02-01

    During embryogenesis vertebral segmentation is initiated by sclerotomal cell migration and condensation around the notochord, forming anlagen of vertebral bodies and intervertebral discs. The factors that govern the segmentation are not clear. Previous research demonstrated that mutations in growth differentiation factor 6 resulted in congenital vertebral fusion, suggesting this factor plays a role in development of vertebral column. In this study, we detected expression and localization of growth differentiation factor 6 in human fetal spinal column, especially in the period of early ossification of vertebrae and the developing intervertebral discs. The extracellular matrix proteins were also examined. Results showed that high levels of growth differentiation factor 6 were expressed in the nucleus pulposus of intervertebral discs and the hypertrophic chondrocytes adjacent to the ossification centre in vertebral bodies, where strong expression of proteoglycan and collagens was also detected. As fetal age increased, the expression of growth differentiation factor 6 was decreased correspondingly with the progress of ossification in vertebral bodies and restricted to cartilaginous regions. This expression pattern and the genetic link to vertebral fusion suggest that growth differentiation factor 6 may play an important role in suppression of ossification to ensure proper vertebral segmentation during spinal development.

  15. The vertebrate ancestral repertoire of visual opsins, transducin alpha subunits and oxytocin/vasopressin receptors was established by duplication of their shared genomic region in the two rounds of early vertebrate genome duplications

    PubMed Central

    2013-01-01

    Background Vertebrate color vision is dependent on four major color opsin subtypes: RH2 (green opsin), SWS1 (ultraviolet opsin), SWS2 (blue opsin), and LWS (red opsin). Together with the dim-light receptor rhodopsin (RH1), these form the family of vertebrate visual opsins. Vertebrate genomes contain many multi-membered gene families that can largely be explained by the two rounds of whole genome duplication (WGD) in the vertebrate ancestor (2R) followed by a third round in the teleost ancestor (3R). Related chromosome regions resulting from WGD or block duplications are said to form a paralogon. We describe here a paralogon containing the genes for visual opsins, the G-protein alpha subunit families for transducin (GNAT) and adenylyl cyclase inhibition (GNAI), the oxytocin and vasopressin receptors (OT/VP-R), and the L-type voltage-gated calcium channels (CACNA1-L). Results Sequence-based phylogenies and analyses of conserved synteny show that the above-mentioned gene families, and many neighboring gene families, expanded in the early vertebrate WGDs. This allows us to deduce the following evolutionary scenario: The vertebrate ancestor had a chromosome containing the genes for two visual opsins, one GNAT, one GNAI, two OT/VP-Rs and one CACNA1-L gene. This chromosome was quadrupled in 2R. Subsequent gene losses resulted in a set of five visual opsin genes, three GNAT and GNAI genes, six OT/VP-R genes and four CACNA1-L genes. These regions were duplicated again in 3R resulting in additional teleost genes for some of the families. Major chromosomal rearrangements have taken place in the teleost genomes. By comparison with the corresponding chromosomal regions in the spotted gar, which diverged prior to 3R, we could time these rearrangements to post-3R. Conclusions We present an extensive analysis of the paralogon housing the visual opsin, GNAT and GNAI, OT/VP-R, and CACNA1-L gene families. The combined data imply that the early vertebrate WGD events contributed to the

  16. The vertebrate ancestral repertoire of visual opsins, transducin alpha subunits and oxytocin/vasopressin receptors was established by duplication of their shared genomic region in the two rounds of early vertebrate genome duplications.

    PubMed

    Lagman, David; Ocampo Daza, Daniel; Widmark, Jenny; Abalo, Xesús M; Sundström, Görel; Larhammar, Dan

    2013-11-02

    Vertebrate color vision is dependent on four major color opsin subtypes: RH2 (green opsin), SWS1 (ultraviolet opsin), SWS2 (blue opsin), and LWS (red opsin). Together with the dim-light receptor rhodopsin (RH1), these form the family of vertebrate visual opsins. Vertebrate genomes contain many multi-membered gene families that can largely be explained by the two rounds of whole genome duplication (WGD) in the vertebrate ancestor (2R) followed by a third round in the teleost ancestor (3R). Related chromosome regions resulting from WGD or block duplications are said to form a paralogon. We describe here a paralogon containing the genes for visual opsins, the G-protein alpha subunit families for transducin (GNAT) and adenylyl cyclase inhibition (GNAI), the oxytocin and vasopressin receptors (OT/VP-R), and the L-type voltage-gated calcium channels (CACNA1-L). Sequence-based phylogenies and analyses of conserved synteny show that the above-mentioned gene families, and many neighboring gene families, expanded in the early vertebrate WGDs. This allows us to deduce the following evolutionary scenario: The vertebrate ancestor had a chromosome containing the genes for two visual opsins, one GNAT, one GNAI, two OT/VP-Rs and one CACNA1-L gene. This chromosome was quadrupled in 2R. Subsequent gene losses resulted in a set of five visual opsin genes, three GNAT and GNAI genes, six OT/VP-R genes and four CACNA1-L genes. These regions were duplicated again in 3R resulting in additional teleost genes for some of the families. Major chromosomal rearrangements have taken place in the teleost genomes. By comparison with the corresponding chromosomal regions in the spotted gar, which diverged prior to 3R, we could time these rearrangements to post-3R. We present an extensive analysis of the paralogon housing the visual opsin, GNAT and GNAI, OT/VP-R, and CACNA1-L gene families. The combined data imply that the early vertebrate WGD events contributed to the evolution of vision and the

  17. A novel regucalcin gene promoter region-related protein: comparison of nucleotide and amino acid sequences in vertebrate species.

    PubMed

    Sawada, Natsumi; Yamaguchi, Masayoshi

    2005-01-01

    The molecular cloning and sequencing of the cDNA coding for a novel regucalcin gene promoter region-related protein (RGPR-p117) from bovine, rabbit and chicken livers was investigated using rapid amplification of cDNA endo (RACE) method. Their nucleotide and amino acid sequences were compared with human, rat and mouse sequences published previously. RGPR-p117 of bovine, rabbit and chicken livers consisted of 1052, 1045, and 929 amino acid residues with calculated molecular mass of 117, 114, and 103 kDa, and estimated pI of 5.64, 5.84, and 5.59, respectively. Comparison analysis revealed that the nucleotide sequences of RGPR-p117 from mammalian species were highly-conserved in their coding region, and the homologies were at least 72.9%. The RGPR-p117 proteins in mammalian species consisted of 1045-1060 amino acids, and had 63.1-90.2% identity. Meanwhile, the nucleotide and amino acid sequences of chicken RGPR-p117 had at least 36.4 and 43.7% identities, respectively. Phylogenetic analysis showed that RGPR-p117 in six vertebrates appears to form a single cluster. Mammalian RGPR-p117 conserved a leucine zipper motif. Moreover, the analysis for subcellular localization of RGPR-p117 from six vertebrates showed the probability of nuclear localization >52.2%; the nuclear localization in rat and mouse was 78.3%. This study demonstrates a great conservation of RGPR-p117 genes throughout evolution.

  18. Threatened, endangered, and vulnerable species of terrestrial vertebrates in the Rocky Mountain Region

    Treesearch

    Deborah M. Finch

    1991-01-01

    This report describes the current status of 67 threatened, endangered, and vulnerable wildlife species in the Rocky Mountain Region of the U.S. Forest Service. Known or potential reasons for population declines and species susceptibility are identified; and distributions, habitats, specialized needs, and perceived threats of individual species are discusses.

  19. Efficient regeneration by activation of neurogenesis in homeostatically quiescent regions of the adult vertebrate brain.

    PubMed

    Berg, Daniel A; Kirkham, Matthew; Beljajeva, Anna; Knapp, Dunja; Habermann, Bianca; Ryge, Jesper; Tanaka, Elly M; Simon, András

    2010-12-01

    In contrast to mammals, salamanders and teleost fishes can efficiently repair the adult brain. It has been hypothesised that constitutively active neurogenic niches are a prerequisite for extensive neuronal regeneration capacity. Here, we show that the highly regenerative salamander, the red spotted newt, displays an unexpectedly similar distribution of active germinal niches with mammals under normal physiological conditions. Proliferation zones in the adult newt brain are restricted to the forebrain, whereas all other regions are essentially quiescent. However, ablation of midbrain dopamine neurons in newts induced ependymoglia cells in the normally quiescent midbrain to proliferate and to undertake full dopamine neuron regeneration. Using oligonucleotide microarrays, we have catalogued a set of differentially expressed genes in these activated ependymoglia cells. This strategy identified hedgehog signalling as a key component of adult dopamine neuron regeneration. These data show that brain regeneration can occur by activation of neurogenesis in quiescent brain regions.

  20. Vertebrate Dissimilarity Due to Turnover and Richness Differences in a Highly Beta-Diverse Region: The Role of Spatial Grain Size, Dispersal Ability and Distance

    PubMed Central

    Calderón-Patrón, Jaime M.; Moreno, Claudia E.; Pineda-López, Rubén; Sánchez-Rojas, Gerardo; Zuria, Iriana

    2013-01-01

    We explore the influence of spatial grain size, dispersal ability, and geographic distance on the patterns of species dissimilarity of terrestrial vertebrates, separating the dissimilarity explained by species replacement (turnover) from that resulting from richness differences. With data for 905 species of terrestrial vertebrates distributed in the Isthmus of Tehuantepec, classified into five groups according to their taxonomy and dispersal ability, we calculated total dissimilarity and its additive partitioning as two components: dissimilarity derived from turnover and dissimilarity derived from richness differences. These indices were compared using fine (10 x 10 km), intermediate (20 x 20 km) and coarse (40 x 40 km) grain grids, and were tested for any correlations with geographic distance. The results showed that total dissimilarity is high for the terrestrial vertebrates in this region. Total dissimilarity, and dissimilarity due to turnover are correlated with geographic distance, and the patterns are clearer when the grain is fine, which is consistent with the distance-decay pattern of similarity. For all terrestrial vertebrates tested on the Isthmus of Tehuantepec both the dissimilarity derived from turnover and the dissimilarity resulting from richness differences make important contributions to total dissimilarity, and dispersal ability does not seem to influence the dissimilarity patterns. These findings support the idea that conservation efforts in this region require a system of interconnected protected areas that embrace the environmental, climatic and biogeographic heterogeneity of the area. PMID:24324840

  1. Species Profiles: Life Histories and Environmental Requirements of Coastal Vertebrates and Invertebrates Pacific Ocean Region. Report 5. The Parrotfishes, Family Scaridae

    DTIC Science & Technology

    1991-03-01

    AND ENVIRONMENTAL REQUIREMENTS OF COASTAL VERTEBRATES AND INVERTEBRATES PACIFIC OCEAN REGION Report 5 THE PARROTFISHES , FAMILY SCARIDAE by R. E. Brock...necessary and Identify by block number) Parrotfishes are highly colorful species inhabiting coral reefs of the world’s trop- ical seas. They may usually be...confusion in the taxonomic literature; there are about 68 species of parrotfishes worldwide. Little is known about the life history of parrotfish

  2. 5C analysis of the Epidermal Differentiation Complex locus reveals distinct chromatin interaction networks between gene-rich and gene-poor TADs in skin epithelial cells.

    PubMed

    Poterlowicz, Krzysztof; Yarker, Joanne L; Malashchuk, Igor; Lajoie, Brian R; Mardaryev, Andrei N; Gdula, Michal R; Sharov, Andrey A; Kohwi-Shigematsu, Terumi; Botchkarev, Vladimir A; Fessing, Michael Y

    2017-09-01

    Mammalian genomes contain several dozens of large (>0.5 Mbp) lineage-specific gene loci harbouring functionally related genes. However, spatial chromatin folding, organization of the enhancer-promoter networks and their relevance to Topologically Associating Domains (TADs) in these loci remain poorly understood. TADs are principle units of the genome folding and represents the DNA regions within which DNA interacts more frequently and less frequently across the TAD boundary. Here, we used Chromatin Conformation Capture Carbon Copy (5C) technology to characterize spatial chromatin interaction network in the 3.1 Mb Epidermal Differentiation Complex (EDC) locus harbouring 61 functionally related genes that show lineage-specific activation during terminal keratinocyte differentiation in the epidermis. 5C data validated by 3D-FISH demonstrate that the EDC locus is organized into several TADs showing distinct lineage-specific chromatin interaction networks based on their transcription activity and the gene-rich or gene-poor status. Correlation of the 5C results with genome-wide studies for enhancer-specific histone modifications (H3K4me1 and H3K27ac) revealed that the majority of spatial chromatin interactions that involves the gene-rich TADs at the EDC locus in keratinocytes include both intra- and inter-TAD interaction networks, connecting gene promoters and enhancers. Compared to thymocytes in which the EDC locus is mostly transcriptionally inactive, these interactions were found to be keratinocyte-specific. In keratinocytes, the promoter-enhancer anchoring regions in the gene-rich transcriptionally active TADs are enriched for the binding of chromatin architectural proteins CTCF, Rad21 and chromatin remodeler Brg1. In contrast to gene-rich TADs, gene-poor TADs show preferential spatial contacts with each other, do not contain active enhancers and show decreased binding of CTCF, Rad21 and Brg1 in keratinocytes. Thus, spatial interactions between gene promoters and

  3. Involvement of Hedgehog and FGF signalling in the lamprey telencephalon: evolution of regionalization and dorsoventral patterning of the vertebrate forebrain.

    PubMed

    Sugahara, Fumiaki; Aota, Shin-ichi; Kuraku, Shigehiro; Murakami, Yasunori; Takio-Ogawa, Yoko; Hirano, Shigeki; Kuratani, Shigeru

    2011-03-01

    Dorsoventral (DV) specification is a crucial step for the development of the vertebrate telencephalon. Clarifying the origin of this mechanism will lead to a better understanding of vertebrate central nervous system (CNS) evolution. Based on the lamprey, a sister group of the gnathostomes (jawed vertebrates), we identified three lamprey Hedgehog (Hh) homologues, which are thought to play central signalling roles in telencephalon patterning. However, unlike in gnathostomes, none of these genes, nor Lhx6/7/8, a marker for the migrating interneuron subtype, was expressed in the ventral telencephalon, consistent with the reported absence of the medial ganglionic eminence (MGE) in this animal. Homologues of Gsh2, Isl1/2 and Sp8, which are involved in the patterning of the lateral ganglionic eminence (LGE) of gnathostomes, were expressed in the lamprey subpallium, as in gnathostomes. Hh signalling is necessary for induction of the subpallium identity in the gnathostome telencephalon. When Hh signalling was inhibited, the ventral identity was disrupted in the lamprey, suggesting that prechordal mesoderm-derived Hh signalling might be involved in the DV patterning of the telencephalon. By blocking fibroblast growth factor (FGF) signalling, the ventral telencephalon was suppressed in the lamprey, as in gnathostomes. We conclude that Hh- and FGF-dependent DV patterning, together with the resultant LGE identity, are likely to have been established in a common ancestor before the divergence of cyclostomes and gnathostomes. Later, gnathostomes would have acquired a novel Hh expression domain corresponding to the MGE, leading to the obtainment of cortical interneurons.

  4. Pax6 expression patterns in Lampetra fluviatilis and Scyliorhinus canicula embryos suggest highly conserved roles in the early regionalization of the vertebrate brain.

    PubMed

    Derobert, Y; Baratte, B; Lepage, M; Mazan, S

    We report expression patterns of the Pax6 gene in the dogfish Scyliorhinus canicula and the lamprey Lampetra fluviatilis during neurulation and at the beginning of organogenesis. At the stages studied, both genes display very similar expression domains in the dorsal forebrain, with a sharp posterior boundary at the diencephalon-mesencephalon border, in the hindbrain, excluding the floor plate and the roof plate, and in the spinal cord. The comparison of these expression patterns with those reported in osteichthyans suggests that the roles played by Pax6 in early brain regionalization have been highly conserved during vertebrate evolution.

  5. Contaminant exposure and potential effects on terrestrial vertebrates residing in the National Capital Region network and Mid-Atlantic network

    USGS Publications Warehouse

    Rattner, B.A.; Ackerson, B.K.

    2006-01-01

    Based upon these and other findings, ecotoxicological monitoring and research investigations of terrestrial vertebrates are warranted at several National Parks. These include Shenandoah National Park, Richmond National Battlefield, Chesapeake & Ohio Canal National Historic Park, Valley Forge National Historic Park, Hopewell Furnace National Historic Site, Monocacy National Battlefield, and Harpers Ferry National Historic Park. The types of investigations vary according to the species present at these parks and potential contaminant threats, but should focus on contemporary use pesticides and herbicides, polychlorinated biphenyls, mercury, lead, and perhaps, emerging contaminants including antibiotics, flame retardants, pharmaceuticals, and surfactants. Other management recommendations include additional training for natural resource staff members in the area of ecotoxicology, inclusion of terrestrial vertebrate contaminant monitoring and the Contaminant Assessment Process (U.S. Geological Survey Biomonitoring of Environmental Status and Trends Project) into the National Park Service Vital Signs Program, development of protocols for hand ling and toxicological analysis of dead or seemingly affected wildlife, consideration of some alternative methods and compounds for pest management and weed control, and use of non-toxic fishing tackle by visitors. 

  6. Vertebrate skeletogenesis

    PubMed Central

    Lefebvre, Véronique; Bhattaram, Pallavi

    2011-01-01

    Vertebrate skeletogenesis consists in elaborating an edifice of more than 200 pieces of bone and cartilage. Each skeletal piece is crafted at a distinct location in the body, is articulated with others, and reaches a specific size, shape, and tissue composition according to both species instructions and individual determinants. This complex, customized body frame fulfills multiple essential tasks. It confers morphological features, allows controlled postures and movements, protects vital organs, houses hematopoiesis, stores minerals, and adsorbs toxins. This review provides an overview of the multiple facets of this ingenious process for experts as well as non-experts of skeletogenesis. We explain how the developing vertebrate uses both specific and ubiquitously expressed genes to generate multipotent mesenchymal cells, specify them to a skeletogenic fate, control their survival and proliferation, and direct their differentiation into cartilage, bone and joint cells. We review milestone discoveries made towards uncovering the intricate networks of regulatory factors that are involved in these processes, with an emphasis on signaling pathways and transcription factors. We describe numerous skeletal malformation and degeneration diseases that occur in humans as a result of mutations in regulatory genes, and explain how these diseases both help and motivate us to further decipher skeletogenic processes. Upon discussing current knowledge and gaps in knowledge in the control of skeletogenesis, we highlight ultimate research goals, and propose research priorities and approaches for future endeavors. PMID:20691853

  7. Three-dimensional structure of the M-region (bare zone) of vertebrate striated muscle myosin filaments by single-particle analysis.

    PubMed

    Al-Khayat, Hind A; Kensler, Robert W; Morris, Edward P; Squire, John M

    2010-11-12

    The rods of anti-parallel myosin molecules overlap at the centre of bipolar myosin filaments to produce an M-region (bare zone) that is free of myosin heads. Beyond the M-region edges, myosin molecules aggregate in a parallel fashion to yield the bridge regions of the myosin filaments. Adjacent myosin filaments in striated muscle A-bands are cross-linked by the M-band. Vertebrate striated muscle myosin filaments have a 3-fold rotational symmetry around their long axes. In addition, at the centre of the M-region, there are three 2-fold axes perpendicular to the filament long axis, giving the whole filament dihedral 32-point group symmetry. Here we describe the three-dimensional structure obtained by a single-particle analysis of the M-region of myosin filaments from goldfish skeletal muscle under relaxing conditions and as viewed in negative stain. This is the first single-particle reconstruction of isolated M-regions. The resulting three-dimensional reconstruction reveals details to about 55 Å resolution of the density distribution in the five main nonmyosin densities in the M-band (M6', M4', M1, M4 and M6) and in the myosin head crowns (P1, P2 and P3) at the M-region edges. The outermost crowns in the reconstruction were identified specifically by their close similarity to the corresponding crown levels in our previously published bridge region reconstructions. The packing of myosin molecules into the M-region structure is discussed, and some unidentified densities are highlighted. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. FRG1, a gene in the FSH muscular dystrophy region on human chromosome 4q35, is highly conserved in vertebrates and invertebrates.

    PubMed

    Grewal, P K; Todd, L C; van der Maarel, S; Frants, R R; Hewitt, J E

    1998-08-17

    The human FRG1 gene maps to human chromosome 4q35 and was identified as a candidate for facioscapulohumeral muscular dystrophy. However, FRG1 is apparently not causally associated with the disease and as yet, its function remains unclear. We have cloned homologues of FRG1 from two additional vertebrates, the mouse and the Japanese puffer fish Fugu rubripes, and investigated the genomic organization of the genes in the two species. The intron/exon structure of the genes is identical throughout the protein coding region, although the Fugu gene is five times smaller than the mouse gene. We have also identified FRG1 homologues in two nematodes; Caenorhabditis elegans and Brugia malayi. The FRG1 protein is highly conserved and contains a lipocalin sequence motif, suggesting it may function as a transport protein.

  9. A ChIP-on-chip tiling array approach detects functional histone-free regions associated with boundaries at vertebrate HOX genes.

    PubMed

    Srivastava, Surabhi; Sowpati, Divya Tej; Garapati, Hita Sony; Puri, Deepika; Dhawan, Jyotsna; Mishra, Rakesh K

    2014-12-01

    Hox genes impart segment identity to body structures along the anterior-posterior axis and are crucial for proper development. A unique feature of the Hox loci is the collinearity between the gene position within the cluster and its spatial expression pattern along the body axis. However, the mechanisms that regulate collinear patterns of Hox gene expression remain unclear, especially in higher vertebrates. We recently identified novel histone-free regions (HFRs) that can act as chromatin boundary elements demarcating successive murine Hox genes and help regulate their precise expression domains (Srivastava et al., 2013). In this report, we describe in detail the ChIP-chip analysis strategy associated with the identification of these HFRs. We also provide the Perl scripts for HFR extraction and quality control analysis for this custom designed tiling array dataset.

  10. Development of the orbital region in the chondrocranium of Caretta caretta. Reconsideration of the vertebrate neurocranium configuration.

    PubMed

    Kuratani, S

    1989-01-01

    By studying the development of the orbital region in the Loggarhead turtle (Caretta caretta) and some placental mammals, it has become clear that the orbital region of the neurocranium should not be regarded as merely a "bowl" to contain the brain, but rather that its ventral part is originally flexured along with the cephalic flexure of the neural tube. At this flexure, the neurocranium is to be divided into 2 parts, the anterior and posterior. The anterior part of the neurocranial sheet is medially perforated by the infundibulum and gives rise to pila metoptica laterally. The post orbital cartilage represents the posterior part. From the above "Bauplan" of the neurocranium, the following conclusions can be drawn: (1) the simple homology of the reptilian and placental mammalian pila metoptica is questionable; (2) the pila antotica is produced by the absorption of the mid-dorsal part of the postorbital cartilage, while the dorsum sellae in mammals is produce by the chondrification of the middle part of the same anlage; (3) homology of the ala hypochiasmatica in mammals with the supratrabecular cartilage in reptiles is more feasible than with the cartilago hypochiasmatica; and (4) the crista sellaris in reptiles is not a part of the primary cranial wall but probably of secondary production.

  11. [Fusion of reconstructed titanic plate, vertebral pedical screws and autogenous granulated cancellous bone graft in posterior occipitocervical region].

    PubMed

    Zhong, Dejun; Song, Yueming

    2006-08-01

    To explore the technique of fusing the reconstructed titanic plate, the C2 pedical screws, and the autogenous granulated cancellous bone graft in the occipitocervical region. From April 2002 to January 2005, 19 patients aged 31-67 years with occipitocervical instability underwent the occipitocervical fusion using the reconstructed plate, C2 pedical screws, and autogenous granulated cancellous bone graft. Of the patients, 8 had complex occipitocervical deformity, 8 had old atlantoaxial fracture and dislocation, 2 had rheumatoid arthritis and anterior dislocation of the atlantoaxial joint, and 1 had cancer of the deltoid process of the axis. No complication occurred during and after operation. The follow-up for an average of 16 months in 19 patients showed that all the patients achieved solid bony fusion in the occipitocervical region. There was no broken plate, broken screw, looseness of the internal fixation or neurovascular injury. The fixation of the C2 pedical screws with the reconstructed titanic plate is reliable, the insertion is easy, and the autogenous granulated cancellous bone graft has a high fusion rate, thus resulting in a satisfactory effect in the occipitocervical fusion.

  12. Building the Vertebrate Spine

    NASA Astrophysics Data System (ADS)

    Pourquié, Olivier

    2008-03-01

    to scoliosis in humans. Finally, the subsequent regional differentiation of the precursors of the vertebrae is controlled by Hox genes, whose collinear expression controls both gastrulation of somite precursors and their subsequent patterning into region-specific types of structures. Therefore somite development provides an outstanding paradigm to study patterning and differentiation in vertebrate embryos.

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

    PubMed

    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.

  14. Vertebrate richness and biogeography in the Big Thicket of Texas

    Treesearch

    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...

  15. Spinal cord compression due to vertebral hemangioma.

    PubMed

    Aksu, Gorkem; Fayda, Merdan; Saynak, Mert; Karadeniz, Ahmet

    2008-02-01

    This article presents a case of multiple vertebral hemangiomas in a 58-year-old man with pain in the dorsal region and bilateral progressive foot numbness. Magnetic resonance imaging revealed multiple vertebral hemangiomas. One hemangioma at the T7 level demonstrated epidural extension, causing spinal cord compression. After treatment with radiotherapy, the patient's symptoms improved significantly.

  16. Modulated contact frequencies at gene-rich loci support a statistical helix model for mammalian chromatin organization

    PubMed Central

    2011-01-01

    Background Despite its critical role for mammalian gene regulation, the basic structural landscape of chromatin in living cells remains largely unknown within chromosomal territories below the megabase scale. Results Here, using the 3C-qPCR method, we investigate contact frequencies at high resolution within interphase chromatin at several mouse loci. We find that, at several gene-rich loci, contact frequencies undergo a periodical modulation (every 90 to 100 kb) that affects chromatin dynamics over large genomic distances (a few hundred kilobases). Interestingly, this modulation appears to be conserved in human cells, and bioinformatic analyses of locus-specific, long-range cis-interactions suggest that it may underlie the dynamics of a significant number of gene-rich domains in mammals, thus contributing to genome evolution. Finally, using an original model derived from polymer physics, we show that this modulation can be understood as a fundamental helix shape that chromatin tends to adopt in gene-rich domains when no significant locus-specific interaction takes place. Conclusions Altogether, our work unveils a fundamental aspect of chromatin dynamics in mammals and contributes to a better understanding of genome organization within chromosomal territories. PMID:21569291

  17. Extracranial vertebral artery intervention.

    PubMed

    Mukherjee, Debabrata; Pineda, Guillermo

    2007-12-01

    Atherosclerosis is the commonest cause of vertebral artery stenosis and has a predilection for the origin and proximal section of the extracranial portion of the vessel and also the intracranial portion of the vessel. Although it has generally been thought that extracranial vertebral artery (ECVA) disease has a more benign outcome compared to intracranial vertebral artery disease, significant occlusive disease of the proximal vertebral artery is the primary cause of vertebral artery ischemia in a significant proportion of patients. We focus on the interventional management of patients with proximal ECVA disease in this article.

  18. Sequencing and analysis of the gene-rich space of cowpea

    PubMed Central

    Timko, Michael P; Rushton, Paul J; Laudeman, Thomas W; Bokowiec, Marta T; Chipumuro, Edmond; Cheung, Foo; Town, Christopher D; Chen, Xianfeng

    2008-01-01

    Background Cowpea, Vigna unguiculata (L.) Walp., is one of the most important food and forage legumes in the semi-arid tropics because of its drought tolerance and ability to grow on poor quality soils. Approximately 80% of cowpea production takes place in the dry savannahs of tropical West and Central Africa, mostly by poor subsistence farmers. Despite its economic and social importance in the developing world, cowpea remains to a large extent an underexploited crop. Among the major goals of cowpea breeding and improvement programs is the stacking of desirable agronomic traits, such as disease and pest resistance and response to abiotic stresses. Implementation of marker-assisted selection and breeding programs is severely limited by a paucity of trait-linked markers and a general lack of information on gene structure and organization. With a nuclear genome size estimated at ~620 Mb, the cowpea genome is an ideal target for reduced representation sequencing. Results We report here the sequencing and analysis of the gene-rich, hypomethylated portion of the cowpea genome selectively cloned by methylation filtration (MF) technology. Over 250,000 gene-space sequence reads (GSRs) with an average length of 610 bp were generated, yielding ~160 Mb of sequence information. The GSRs were assembled, annotated by BLAST homology searches of four public protein annotation databases and four plant proteomes (A. thaliana, M. truncatula, O. sativa, and P. trichocarpa), and analyzed using various domain and gene modeling tools. A total of 41,260 GSR assemblies and singletons were annotated, of which 19,786 have unique GenBank accession numbers. Within the GSR dataset, 29% of the sequences were annotated using the Arabidopsis Gene Ontology (GO) with the largest categories of assigned function being catalytic activity and metabolic processes, groups that include the majority of cellular enzymes and components of amino acid, carbohydrate and lipid metabolism. A total of 5,888 GSRs had

  19. Two Rare Variants of Left Vertebral Artery.

    PubMed

    Singh, Rajani

    2017-02-15

    Though the variations of vertebral artery are clinically asymptomatic yet abnormalities are of diagnostic importance either prior to vascular surgery in the neck region or in patients of intravascular diseases such as arteriovenous malformations or cerebral aneurysms. Therefore, the aim of the study is to bring out 2 variations in the configuration of vertebral artery and their clinical implication. During dissection of thorax of 2 female cadavers, 2 different variants of configurations of left vertebral arteries were observed. In 1 patient, the left vertebral artery arose aberrantly from arch of aorta between left common carotid artery and left subclavian artery. This artery then, following oblique course, abnormally entered into foramen transversarium of C4 vertebra. In the second patient, the left common stump emerged from arch of aorta in the left side of left common carotid artery and then instantly bifurcated into vertebral artery and subclavian artery. Then following the usual oblique course, the left vertebral artery anomalously entered into foramen transversarium of C3 vertebra at the level of upper border of thyroid cartilage. The knowledge of these rare variations in the origin of vertebral artery is of paramount importance to surgeons performing surgery in neck region, radiologist performing angiography to avoid misinterpretation of radiographs and to anatomists for rare variations in academics and research.

  20. The evolution of vertebral formulae in Hominoidea.

    PubMed

    Thompson, Nathan E; Almécija, Sergio

    2017-09-01

    Primate vertebral formulae have long been investigated because of their link to locomotor behavior and overall body plan. Knowledge of the ancestral vertebral formulae in the hominoid tree of life is necessary to interpret the pattern of evolution among apes, and to critically evaluate the morphological adaptations involved in the transition to hominin bipedalism. Though many evolutionary hypotheses have been proposed based on living and fossil species, the application of quantitative phylogenetic methods for thoroughly reconstructing ancestral vertebral formulae and formally testing patterns of vertebral evolution is lacking. To estimate the most probable scenarios of hominoid vertebral evolution, we utilized an iterative ancestral state reconstruction approach to determine likely ancestral vertebral counts in apes, humans, and other anthropoid out-groups. All available ape and hominin fossil taxa with an inferred regional vertebral count were included in the analysis. Sensitivity iterations were performed both by changing the phylogenetic position of fossil taxa with a contentious placement, and by changing the inferred number of vertebrae in taxa with uncertain morphology. Our ancestral state reconstruction results generally support a short-backed hypothesis of human evolution, with a Pan-Homo last common ancestor possessing a vertebral formulae of 7:13:4:6 (cervical:thoracic:lumbar:sacral). Our results indicate that an initial reduction in lumbar vertebral count and increase in sacral count is a synapomorphy of crown hominoids (supporting an intermediate-backed hypothesis for the origins of the great ape-human clade). Further reduction in lumbar count occurs independently in orangutans and African apes. Our results highlight the complexity and homoplastic nature of vertebral count evolution, and give little support to the long-backed hypothesis of human evolution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Testing Skills in Vertebrates

    ERIC Educational Resources Information Center

    Funk, Mildred Sears; Tosto, Pat

    2007-01-01

    In this article, the authors present a project that gives students examples of basic skills that many vertebrate species develop as they grow and function in their ecosystem. These activities involve information gathering about surroundings, learning how to use objects, and tracking and searching skills. Different vertebrate species may acquire…

  2. Testing Skills in Vertebrates

    ERIC Educational Resources Information Center

    Funk, Mildred Sears; Tosto, Pat

    2007-01-01

    In this article, the authors present a project that gives students examples of basic skills that many vertebrate species develop as they grow and function in their ecosystem. These activities involve information gathering about surroundings, learning how to use objects, and tracking and searching skills. Different vertebrate species may acquire…

  3. Developmental control of segment numbers in vertebrates

    PubMed Central

    Gomez, Céline; Pourquié, Olivier

    2011-01-01

    Segmentation or metamery in vertebrates is best illustrated by the repetition of the vertebrae and ribs, their associated skeletal muscles and blood vessels, and the spinal nerves and ganglia. The segment number varies tremendously among the different vertebrate species, ranging from as few as six vertebrae in some frogs to as many as several hundred in some snakes and fish. In vertebrates, metameric segments or somites form sequentially during body axis formation. This results in the embryonic axis becoming entirely segmented into metameric units from the level of the otic vesicle almost to the very tip of the tail. The total segment number mostly depends on two parameters: (1) the control of the posterior growth of the body axis during somitogenesis—more same-size segments can be formed in a longer axis and (2) segment size—more smaller-size segments can be formed in a same-size body axis. During evolution, independent variations of these parameters could explain the huge diversity in segment numbers observed among vertebrate species. These variations in segment numbers are accompanied by diversity in the regionalization of the vertebral column. For example, amniotes can exhibit up to five different types of vertebrae: cervical, thoracic, lumbar, sacral and caudal, the number of which varies according to the species. This regionalization of the vertebral column is controlled by the Hox family of transcription factors. We propose that during development, dissociation of the Hox- and segmentation-clock-dependent vertebral patterning systems explains the enormous diversity of vertebral formulae observed in vertebrates. PMID:19621429

  4. Climate change and marine vertebrates.

    PubMed

    Sydeman, William J; Poloczanska, Elvira; Reed, Thomas E; Thompson, Sarah Ann

    2015-11-13

    Climate change impacts on vertebrates have consequences for marine ecosystem structures and services. We review marine fish, mammal, turtle, and seabird responses to climate change and discuss their potential for adaptation. Direct and indirect responses are demonstrated from every ocean. Because of variation in research foci, observed responses differ among taxonomic groups (redistributions for fish, phenology for seabirds). Mechanisms of change are (i) direct physiological responses and (ii) climate-mediated predator-prey interactions. Regional-scale variation in climate-demographic functions makes range-wide population dynamics challenging to predict. The nexus of metabolism relative to ecosystem productivity and food webs appears key to predicting future effects on marine vertebrates. Integration of climate, oceanographic, ecosystem, and population models that incorporate evolutionary processes is needed to prioritize the climate-related conservation needs for these species. Copyright © 2015, American Association for the Advancement of Science.

  5. Vertebral Compression Fractures

    MedlinePlus

    ... OI: Information on Vertebral Compression Fractures 804 W. Diamond Ave., Ste. 210 Gaithersburg, MD 20878 (800) 981- ... osteogenesis imperfecta contact : Osteogenesis Imperfecta Foundation 804 W. Diamond Avenue, Suite 210, Gaithersburg, MD 20878 Tel: 800- ...

  6. A gene-rich linkage map in the dioecious species Actinidia chinensis (kiwifruit) reveals putative X/Y sex-determining chromosomes.

    PubMed

    Fraser, Lena G; Tsang, Gianna K; Datson, Paul M; De Silva, H Nihal; Harvey, Catherine F; Gill, Geoffrey P; Crowhurst, Ross N; McNeilage, Mark A

    2009-03-10

    The genus Actinidia (kiwifruit) consists of woody, scrambling vines, native to China, and only recently propagated as a commercial crop. All species described are dioecious, but the genetic mechanism for sex-determination is unknown, as is the genetic basis for many of the cluster of characteristics making up the unique fruit. It is, however, an important crop in the New Zealand economy, and a classical breeding program would benefit greatly by knowledge of the trait alleles carried by both female and male parents. The application of marker assisted selection (MAS) in seedling populations would also aid the accurate and efficient development of novel fruit types for the market. Gene-rich female, male and consensus linkage maps of the diploid species A. chinensis have been constructed with 644 microsatellite markers. The maps consist of twenty-nine linkage groups corresponding to the haploid number n = 29. We found that sex-linked sequence characterized amplified region (SCAR) markers and the 'Flower-sex' phenotype consistently mapped to a single linkage group, in a subtelomeric region, in a section of inconsistent marker order. The region also contained markers of expressed genes, some of unknown function. Recombination, assessed by allelic distribution and marker order stability, was, in the remainder of the linkage group, in accordance with other linkage groups. Fully informative markers to other genes in this linkage group identified the comparative linkage group in the female map, where recombination ratios determining marker order were similar to the autosomes. We have created genetic linkage maps that define the 29 linkage groups of the haploid genome, and have revealed the position and extent of the sex-determining locus in A. chinensis. As all Actinidia species are dioecious, we suggest that the sex-determining loci of other Actinidia species will be similar to that region defined in our maps. As the extent of the non-recombining region is limited, our

  7. A gene-rich linkage map in the dioecious species Actinidia chinensis (kiwifruit) reveals putative X/Y sex-determining chromosomes

    PubMed Central

    Fraser, Lena G; Tsang, Gianna K; Datson, Paul M; De Silva, H Nihal; Harvey, Catherine F; Gill, Geoffrey P; Crowhurst, Ross N; McNeilage, Mark A

    2009-01-01

    Background The genus Actinidia (kiwifruit) consists of woody, scrambling vines, native to China, and only recently propagated as a commercial crop. All species described are dioecious, but the genetic mechanism for sex-determination is unknown, as is the genetic basis for many of the cluster of characteristics making up the unique fruit. It is, however, an important crop in the New Zealand economy, and a classical breeding program would benefit greatly by knowledge of the trait alleles carried by both female and male parents. The application of marker assisted selection (MAS) in seedling populations would also aid the accurate and efficient development of novel fruit types for the market. Results Gene-rich female, male and consensus linkage maps of the diploid species A. chinensis have been constructed with 644 microsatellite markers. The maps consist of twenty-nine linkage groups corresponding to the haploid number n = 29. We found that sex-linked sequence characterized amplified region (SCAR) markers and the 'Flower-sex' phenotype consistently mapped to a single linkage group, in a subtelomeric region, in a section of inconsistent marker order. The region also contained markers of expressed genes, some of unknown function. Recombination, assessed by allelic distribution and marker order stability, was, in the remainder of the linkage group, in accordance with other linkage groups. Fully informative markers to other genes in this linkage group identified the comparative linkage group in the female map, where recombination ratios determining marker order were similar to the autosomes. Conclusion We have created genetic linkage maps that define the 29 linkage groups of the haploid genome, and have revealed the position and extent of the sex-determining locus in A. chinensis. As all Actinidia species are dioecious, we suggest that the sex-determining loci of other Actinidia species will be similar to that region defined in our maps. As the extent of the non

  8. Vertebral sclerosis in adults.

    PubMed Central

    Russell, A S; Percy, J S; Lentle, B C

    1979-01-01

    Narrowing of the intervertebral disc space with sclerosis of the adjacent vertebral bodies may occur as a consequence of infection, neoplasia, trauma, or rheumatic disease. Some patients have been described with backache and these radiological appearances without any primary cause being apparent. The lesions were almost always of 1 or, at most, 2 vertebrae and most frequently involved the inferior margin of L4. We describe 3 patients with far more extensive vertebral involvement and present the clinical, radiological, scintiscan, and histological findings. The only patient we have seen with the better known, isolated L4/5 lesion was shown on biopsy to have staphylococcal osteomyelitis. For this reason we would still recommend a biopsy of all such sclerotic vertebral lesions if they occur in the absence of other rheumatic disease. Images PMID:434941

  9. Incidental vertebral lesions.

    PubMed

    Coumans, Jean-Valery C E; Walcott, Brian P

    2011-12-01

    Incidental vertebral lesions on imaging of the spine are commonly encountered in clinical practice. Contributing factors include the aging population, the increasing prevalence of back pain, and increased usage of MR imaging. Additionally, refinements in CT and MR imaging have increased the number of demonstrable lesions. The management of incidental findings varies among practitioners and commonly depends more on practice style than on data or guidelines. In this article we review incidental findings within the vertebral column and review management of these lesions, based on available Class III data.

  10. Autophagy during vertebrate development.

    PubMed

    Aburto, María R; Hurlé, Juan M; Varela-Nieto, Isabel; Magariños, Marta

    2012-08-02

    Autophagy is an evolutionarily conserved catabolic process by which cells degrade their own components through the lysosomal machinery. In physiological conditions, the mechanism is tightly regulated and contributes to maintain a balance between synthesis and degradation in cells undergoing intense metabolic activities. Autophagy is associated with major tissue remodeling processes occurring through the embryonic, fetal and early postnatal periods of vertebrates. Here we survey current information implicating autophagy in cellular death, proliferation or differentiation in developing vertebrates. In developing systems, activation of the autophagic machinery could promote different outcomes depending on the cellular context. Autophagy is thus an extraordinary tool for the developing organs and tissues.

  11. Vertebral-Basilar Insufficiency

    PubMed Central

    Cape, Ronald D. T.; Hogan, David B.

    1983-01-01

    Vertebral-basilar ischemia can result in giddiness, transient ischemic attacks, and drop attacks. Management involves controlling blood pressure, getting the patient to stop smoking, controlling diabetes and/or hyperlipidemia, and instituting antiplatelet therapy. Several facets of this problem remain unexplained. PMID:21283322

  12. The vertebral column of Australopithecus sediba.

    PubMed

    Williams, Scott A; Ostrofsky, Kelly R; Frater, Nakita; Churchill, Steven E; Schmid, Peter; Berger, Lee R

    2013-04-12

    Two partial vertebral columns of Australopithecus sediba grant insight into aspects of early hominin spinal mobility, lumbar curvature, vertebral formula, and transitional vertebra position. Au. sediba likely possessed five non-rib-bearing lumbar vertebrae and five sacral elements, the same configuration that occurs modally in modern humans. This finding contrasts with other interpretations of early hominin regional vertebral numbers. Importantly, the transitional vertebra is distinct from and above the last rib-bearing vertebra in Au. sediba, resulting in a functionally longer lower back. This configuration, along with a strongly wedged last lumbar vertebra and other indicators of lordotic posture, would have contributed to a highly flexible spine that is derived compared with earlier members of the genus Australopithecus and similar to that of the Nariokotome Homo erectus skeleton.

  13. Head segmentation in vertebrates

    PubMed Central

    Kuratani, Shigeru; Schilling, Thomas

    2008-01-01

    Classic theories of vertebrate head segmentation clearly exemplify the idealistic nature of comparative embryology prior to the 20th century. Comparative embryology aimed at recognizing the basic, primary structure that is shared by all vertebrates, either as an archetype or an ancestral developmental pattern. Modern evolutionary developmental (Evo-Devo) studies are also based on comparison, and therefore have a tendency to reduce complex embryonic anatomy into overly simplified patterns. Here again, a basic segmental plan for the head has been sought among chordates. We convened a symposium that brought together leading researchers dealing with this problem, in a number of different evolutionary and developmental contexts. Here we give an overview of the outcome and the status of the field in this modern era of Evo-Devo. We emphasize the fact that the head segmentation problem is not fully resolved, and we discuss new directions in the search for hints for a way out of this maze. PMID:20607135

  14. Viruses of lower vertebrates.

    PubMed

    Essbauer, S; Ahne, W

    2001-08-01

    Viruses of lower vertebrates recently became a field of interest to the public due to increasing epizootics and economic losses of poikilothermic animals. These were reported worldwide from both wildlife and collections of aquatic poikilothermic animals. Several RNA and DNA viruses infecting fish, amphibians and reptiles have been studied intensively during the last 20 years. Many of these viruses induce diseases resulting in important economic losses of lower vertebrates, especially in fish aquaculture. In addition, some of the DNA viruses seem to be emerging pathogens involved in the worldwide decline in wildlife. Irido-, herpes- and polyomavirus infections may be involved in the reduction in the numbers of endangered amphibian and reptile species. In this context the knowledge of several important RNA viruses such as orthomyxo-, paramyxo-, rhabdo-, retro-, corona-, calici-, toga-, picorna-, noda-, reo- and birnaviruses, and DNA viruses such as parvo-, irido-, herpes-, adeno-, polyoma- and poxviruses, is described in this review.

  15. Correlation between Hox code and vertebral morphology in archosaurs.

    PubMed

    Böhmer, Christine; Rauhut, Oliver W M; Wörheide, Gert

    2015-07-07

    The relationship between developmental genes and phenotypic variation is of central interest in evolutionary biology. An excellent example is the role of Hox genes in the anteroposterior regionalization of the vertebral column in vertebrates. Archosaurs (crocodiles, dinosaurs including birds) are highly variable both in vertebral morphology and number. Nevertheless, functionally equivalent Hox genes are active in the axial skeleton during embryonic development, indicating that the morphological variation across taxa is likely owing to modifications in the pattern of Hox gene expression. By using geometric morphometrics, we demonstrate a correlation between vertebral Hox code and quantifiable vertebral morphology in modern archosaurs, in which the boundaries between morphological subgroups of vertebrae can be linked to anterior Hox gene expression boundaries. Our findings reveal homologous units of cervical vertebrae in modern archosaurs, each with their specific Hox gene pattern, enabling us to trace these homologies in the extinct sauropodomorph dinosaurs, a group with highly variable vertebral counts. Based on the quantifiable vertebral morphology, this allows us to infer the underlying genetic mechanisms in vertebral evolution in fossils, which represents not only an important case study, but will lead to a better understanding of the origin of morphological disparity in recent archosaur vertebral columns.

  16. Reintroduction of locally extinct vertebrates impacts arid soil fungal communities.

    PubMed

    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.

  17. Correlation between Hox code and vertebral morphology in archosaurs

    PubMed Central

    Böhmer, Christine; Rauhut, Oliver W. M.; Wörheide, Gert

    2015-01-01

    The relationship between developmental genes and phenotypic variation is of central interest in evolutionary biology. An excellent example is the role of Hox genes in the anteroposterior regionalization of the vertebral column in vertebrates. Archosaurs (crocodiles, dinosaurs including birds) are highly variable both in vertebral morphology and number. Nevertheless, functionally equivalent Hox genes are active in the axial skeleton during embryonic development, indicating that the morphological variation across taxa is likely owing to modifications in the pattern of Hox gene expression. By using geometric morphometrics, we demonstrate a correlation between vertebral Hox code and quantifiable vertebral morphology in modern archosaurs, in which the boundaries between morphological subgroups of vertebrae can be linked to anterior Hox gene expression boundaries. Our findings reveal homologous units of cervical vertebrae in modern archosaurs, each with their specific Hox gene pattern, enabling us to trace these homologies in the extinct sauropodomorph dinosaurs, a group with highly variable vertebral counts. Based on the quantifiable vertebral morphology, this allows us to infer the underlying genetic mechanisms in vertebral evolution in fossils, which represents not only an important case study, but will lead to a better understanding of the origin of morphological disparity in recent archosaur vertebral columns. PMID:26085583

  18. Morphological modularity in the vertebral column of Felidae (Mammalia, Carnivora).

    PubMed

    Randau, Marcela; Goswami, Anjali

    2017-06-09

    Previous studies have demonstrated that the clear morphological differences among vertebrae across the presacral column are accompanied by heterogeneous functional signals in vertebral shape. Further, several lines of evidence suggest that the mammalian axial skeleton is a highly modular structure. These include its composition of serial units, a trade-off between high shape variance and strong conservation of vertebral count, and direct association of regions with anterior expression sites of Hox genes. Here we investigate the modular organisation of the presacral vertebral column of modern cats (Felidae, Carnivora, Mammalia) with pairwise comparisons of vertebral shape covariation (i.e. integration) and evaluate our results against hypotheses of developmental and functional modularity. We used three-dimensional geometric morphometrics to quantify vertebral shape and then assessed integration between pairs of vertebrae with phylogenetic two-block partial least square analysis (PLS). Six modules were identified in the pairwise analyses (vertebrae included are designated as 'C' for cervical, 'T' for thoracic, and 'L' for lumbar): an anterior module (C1 to T1); a transitional module situated between the last cervicals and first thoracics (C6 to T2); an anterior to middle thoracic set (T4 to T8); an anticlinal module (T10 and T11); a posterior set composed of the last two thoracics and lumbars (T12 to L7); and a module showing covariation between the cervicals and the posterior set (T12 to L7). These modules reflect shared developmental pathways, ossification timing, and observed ecological shape diversification in living species of felids. We show here that patterns of shape integration reflect modular organisation of the vertebral column of felids. Whereas this pattern corresponds with hypotheses of developmental and functional regionalisation in the axial skeleton, it does not simply reflect major vertebral regions. This modularity may also have permitted vertebral

  19. Comparative Studies of Vertebrate Beta Integrin Genes and Proteins: Ancient Genes in Vertebrate Evolution

    PubMed Central

    Holmes, Roger S.; Rout, Ujjwal K.

    2011-01-01

    Intregins are heterodimeric α- and β-subunit containing membrane receptor proteins which serve various cell adhesion roles in tissue repair, hemostasis, immune response, embryogenesis and metastasis. At least 18 α- (ITA or ITGA) and 8 β-integrin subunits (ITB or ITGB) are encoded on mammalian genomes. Comparative ITB amino acid sequences and protein structures and ITB gene locations were examined using data from several vertebrate genome projects. Vertebrate ITB genes usually contained 13–16 coding exons and encoded protein subunits with ∼800 amino acids, whereas vertebrate ITB4 genes contained 36-39 coding exons and encoded larger proteins with ∼1800 amino acids. The ITB sequences exhibited several conserved domains including signal peptide, extracellular β-integrin, β-tail domain and integrin β-cytoplasmic domains. Sequence alignments of the integrin β-cytoplasmic domains revealed highly conserved regions possibly for performing essential functions and its maintenance during vertebrate evolution. With the exception of the human ITB8 sequence, the other ITB sequences shared a predicted 19 residue α-helix for this region. Potential sites for regulating human ITB gene expression were identified which included CpG islands, transcription factor binding sites and microRNA binding sites within the 3′-UTR of human ITB genes. Phylogenetic analyses examined the relationships of vertebrate beta-integrin genes which were consistent with four major groups: 1: ITB1, ITB2, ITB7; 2: ITB3, ITB5, ITB6; 3: ITB4; and 4: ITB8 and a common evolutionary origin from an ancestral gene, prior to the appearance of fish during vertebrate evolution. The phylogenetic analyses revealed that ITB4 is the most likely primordial form of the vertebrate β integrin subunit encoding genes, that is the only β subunit expressed as a constituent of the sole integrin receptor ‘α6β4’ in the hemidesmosomes of unicellular organisms. PMID:24970121

  20. Non-contiguous multifocal vertebral osteomyelitis caused by Serratia marcescens.

    PubMed

    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.

  1. What's new in vertebral cementoplasty?

    PubMed Central

    Guarnieri, Gianluigi; Giurazza, Francesco; Manfrè, Luigi

    2016-01-01

    Vertebral cementoplasty is a well-known mini-invasive treatment to obtain pain relief in patients affected by vertebral porotic fractures, primary or secondary spine lesions and spine trauma through intrametameric cement injection. Two major categories of treatment are included within the term vertebral cementoplasty: the first is vertebroplasty in which a simple cement injection in the vertebral body is performed; the second is assisted technique in which a device is positioned inside the metamer before the cement injection to restore vertebral height and allow a better cement distribution, reducing the kyphotic deformity of the spine, trying to obtain an almost normal spine biomechanics. We will describe the most advanced techniques and indications of vertebral cementoplasty, having recently expanded the field of applications to not only patients with porotic fractures but also spine tumours and trauma. PMID:26728798

  2. Diagnosing vertebral fractures: missed opportunities.

    PubMed

    Borges, João Lindolfo Cunha; Maia, Julianne Lira; Silva, Renata Faria; Lewiecki, Edward Michael

    2015-01-01

    Vertebral fractures are the single most common type of osteoporotic fracture. Postmenopausal women are at increased risk for osteoporotic vertebral fractures compared with women of childbearing age. Vertebral fractures are associated with an increase in morbidity, mortality, and high risk of a subsequent vertebral fracture, regardless of bone mineral density. Despite the common occurrence and serious consequences of vertebral fractures, they are often unrecognized or misdiagnosed by radiologists. Moreover, vertebral fractures may be described by variable terminology that can confuse rather than enlighten referring physicians. We conducted a survey of spine X-ray reports from a group of postmenopausal women screened for participation in a study of osteoporosis at Centro de Pesquisa Clínica do Brasil. A descriptive analysis evaluated the variability of reports in 7 patients. Four independent general radiologists issued reports assessing vertebral fractures through a blinded analysis. The objective of this study was to evaluate for consistency in these reports. The analysis found marked variability in the diagnosis of vertebral fractures and the terminology used to describe them. In community medical practices, such variability could lead to differences in the management of patients with osteoporosis, with the potential for undertreatment or overtreatment depending on clinical circumstances. Accurate and unambiguous reporting of vertebral fractures is likely to be associated with improved clinical outcomes. Copyright © 2015 Elsevier Editora Ltda. All rights reserved.

  3. Spermatogenesis in nonmammalian vertebrates.

    PubMed

    Pudney, J

    1995-12-15

    Spermatogenesis appears to be a fairly conserved process throughout the vertebrate series. Thus, spermatogonia develop into spermatocytes that undergo meiosis to produce spermatids which enter spermiogenesis where they undergo a morphological transformation into spermatozoa. There is, however, variation amongst the vertebrates in how germ cell development and maturation is accomplished. This difference can be broadly divided into two distinct patterns, one present in anamniotes (fish, amphibia) and the other in amniotes (reptiles, birds, mammals). For anamniotes, spermatogenesis occurs in spermatocysts (cysts) which for most species develop within seminiferous lobules. Cysts are produced when a Sertoli cell becomes associated with a primary spermatogonium. Mitotic divisions of the primary spermatogonium produce a cohort of secondary spermatogonia that are enclosed by the Sertoli cell which forms the wall of the cyst. With spermatogenic progression a clone of isogeneic spermatozoa is produced which are released, by rupture of the cyst, into the lumen of the seminiferous lobule. Following spermiation, the Sertoli cell degenerates. For anamniotes, therefore, there is no permanent germinal epithelium since spermatocysts have to be replaced during successive breeding seasons. By contrast, spermatogenesis in amniotes does not occur in cysts but in seminiferous tubules that possess a permanent population of Sertoli cells and spermatogonia which act as a germ cell reservoir for succeeding bouts of spermatogenic activity. There is, in general, a greater variation in the organization of the testis and pattern of spermatogenesis in the anamniotes compared to amniotes. This is primarily due to the fact there is more reproductive diversity in anamniotes ranging from a relatively unspecialized condition where gametes are simply released into the aqueous environment to highly specialized strategies involving internal fertilization. These differences are obviously reflected in the

  4. The cortical shell architecture of human cervical vertebral bodies.

    PubMed

    Panjabi, M M; Chen, N C; Shin, E K; Wang, J L

    2001-11-15

    An anatomic study of cervical vertebral bodies. To provide quantitative information on the cortical shell architecture of the middle and lower cervical vertebral bodies. Some external dimensions have been measured, but little quantitative data exists for the cortical shell architecture of the vertebral bodies of the cervical spine. Twenty-one human cervical vertebral bodies (C3-C7) were sectioned along parasagittal planes into five 1.7-mm thin slices for each vertebra. Radiographs of each slice were digitized, and external and internal dimensions were measured. Averages and standard deviations were computed. Single factor analysis of variance was used to determine significant (P < 0.05) differences between the vertebral levels. The superior endplate was thickest in the posterior region (range 0.74-0.89 mm) and thinnest in the anterior region (range 0.44-0.56 mm). The inferior endplate was thickest in the anterior region (range 0.61-0.81 mm) and thinnest in the posterior region (range 0.49-0.62 mm). In the central region, the superior endplate (range 0.42-0.58 mm) was thinner than the inferior endplate (range 0.53-0.64 mm). Variation with vertebral level was dependent on the dimension studied. Comprehensive quantitative anatomic data of the middle and lower cervical vertebral bodies have been obtained. This may be useful in improving the understanding of the three-column and other vertebral-fracture theories, the fidelity of the finite element models of cervical spine, and the designs of surgical instrumentation.

  5. Organizational heterogeneity of vertebrate genomes.

    PubMed

    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.

  6. Chemical ecology of vertebrate carrion

    USDA-ARS?s Scientific Manuscript database

    Vertebrate carrion is a nutrient-rich, ephemeral resource that is utilized by many different organisms ranging from vertebrate and invertebrate scavengers to microbes. The organisms that consume carrion play an important ecological role, as decomposition is vital to ecosystem function. Without the...

  7. Opportunistic Identification of Vertebral Fractures.

    PubMed

    Adams, Judith E

    2016-01-01

    Vertebral fractures are powerful predictors of future fracture, so, their identification is important to ensure that patients are commenced on appropriate bone protective or bone-enhancing therapy. Risk factors (e.g., low bone mineral density and increasing age) and symptoms (back pain, loss of height) may herald the presence of vertebral fractures, which are usually confirmed by performing spinal radiographs or, increasingly, using vertebral fracture assessment with dual-energy X-ray absorptiometry scanners. However, a large number (30% or more) of vertebral fractures are asymptomatic and do not come to clinical attention. There is, therefore, scope for opportunistic (fortuitous) identification of vertebral fractures from various imaging modalities (radiographs, computed tomography, magnetic resonance imaging, and radionuclide scans) performed for other clinical indications and which include the spine in the field of view, with midline sagittal reformatted images from computed tomography having the greatest potential for such opportunistic detection. Numerous studies confirm this potential for identification but consistently find underreporting of vertebral fractures. So, a valuable opportunity to improve the management of patients at increased risk of future fracture is being squandered. Educational training programs for all clinicians and constant reiteration, stressing the importance of the accurate and clear reporting of vertebral fractures ("you only see what you look for"), can improve the situation, and automated computer-aided diagnostic tools also show promise to solve the problem of this underreporting of vertebral fractures. Copyright © 2016. Published by Elsevier Inc.

  8. Congenital abnormalities of the vertebral column in ferrets.

    PubMed

    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.

  9. Functional aspects of strepsirrhine lumbar vertebral bodies and spinous processes.

    PubMed

    Shapiro, Liza J; Simons, Cornelia V M

    2002-06-01

    The relationship between form and function in the lumbar vertebral column has been well documented among platyrrhines and especially catarrhines, while functional studies of postcranial morphology among strepsirrhines have concentrated predominantly on the limbs. This morphometric study investigates biomechanically relevant attributes of the lumbar vertebral morphology of 20 species of extant strepsirrhines. With this extensive sample, our goal is to address the influence of positional behavior on lumbar vertebral form while also assessing the effects of body size and phylogenetic history. The results reveal distinctions in lumbar vertebral morphology among strepsirrhines in functional association with their habitual postures and primary locomotor behaviors. In general, strepsirrhines that emphasize pronograde posture and quadrupedal locomotion combined with leaping (from a pronograde position) have the relatively longest lumbar regions and lumbar vertebral bodies, features promoting sagittal spinal flexibility. Indrids and galagonids that rely primarily on vertical clinging and leaping with orthograde posture share a relatively short (i.e., stable and resistant to bending) lumbar region, although the length of individual lumbar vertebral bodies varies phylogenetically and possibly allometrically. The other two vertical clingers and leapers, Hapalemur and Lepilemur, more closely resemble the pronograde, quadrupedal taxa. The specialized, suspensory lorids have relatively short lumbar regions as well, but the lengths of their lumbar regions are influenced by body size, and Arctocebus has dramatically longer vertebral bodies than do the other lorids. Lumbar morphology among galagonids appears to reflect a strong phylogenetic signal superimposed on a functional one. In general, relative length of the spinous processes follows a positively allometric trend, although lorids (especially the larger-bodied forms) have relatively short spinous processes for their body size

  10. Evolutionary growth process of highly conserved sequences in vertebrate genomes.

    PubMed

    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.

  11. Differential segmental growth of the vertebral column of the rat (Rattus norvegicus).

    PubMed

    Bergmann, Philip J; Melin, Amanda D; Russell, Anthony P

    2006-01-01

    Despite the pervasive occurrence of segmental morphologies in the animal kingdom, the study of segmental growth is almost entirely lacking, but may have significant implications for understanding the development of these organisms. We investigate the segmental and regional growth of the entire vertebral column of the rat (Rattus norvegicus) by fitting a Gompertz curve to length and age data for each vertebra and each vertebral region. Regional lengths are calculated by summing constituent vertebral lengths and intervertebral space lengths for cervical, thoracic, lumbar, sacral, and caudal regions. Gompertz curves allow for the estimation of parameters representing neonatal and adult vertebral and regional lengths, as well as initial growth rate and the rate of exponential growth decay. Findings demonstrate differences between neonatal and adult rats in terms of relative vertebral lengths, and differential growth rates between sequential vertebrae and vertebral regions. Specifically, relative differences in the length of vertebrae indicate increasing differences caudad. Vertebral length in neonates increases from the atlas to the middle of the thoracic series and decreases in length caudad, while adult vertebral lengths tend to increase caudad. There is also a general trend of increasing vertebral and regional initial growth and rate of growth decay caudad. Anteroposterior patterns of growth are sexually dimorphic, with males having longer vertebrae than females at any given age. Differences are more pronounced (a) increasingly caudad along the body axis, and (b) in adulthood than in neonates. Elucidated patterns of growth are influenced by a combination of developmental, functional, and genetic factors.

  12. Comparative anatomy: all vertebrates do have vertebrae.

    PubMed

    Janvier, Philippe

    2011-09-13

    In contrast to lampreys and jawed vertebrates, hagfishes were thought to lack vertebrae. Now, long overlooked vertebral rudiments have been analysed in hagfish, suggesting that vertebrae existed in the last common ancestor of all vertebrates.

  13. A revised metric for quantifying body shape in vertebrates.

    PubMed

    Collar, David C; Reynaga, Crystal M; Ward, Andrea B; Mehta, Rita S

    2013-08-01

    Vertebrates exhibit tremendous diversity in body shape, though quantifying this variation has been challenging. In the past, researchers have used simplified metrics that either describe overall shape but reveal little about its anatomical basis or that characterize only a subset of the morphological features that contribute to shape variation. Here, we present a revised metric of body shape, the vertebrate shape index (VSI), which combines the four primary morphological components that lead to shape diversity in vertebrates: head shape, length of the second major body axis (depth or width), and shape of the precaudal and caudal regions of the vertebral column. We illustrate the usefulness of VSI on a data set of 194 species, primarily representing five major vertebrate clades: Actinopterygii, Lissamphibia, Squamata, Aves, and Mammalia. We quantify VSI diversity within each of these clades and, in the course of doing so, show how measurements of the morphological components of VSI can be obtained from radiographs, articulated skeletons, and cleared and stained specimens. We also demonstrate that head shape, secondary body axis, and vertebral characteristics are important independent contributors to body shape diversity, though their importance varies across vertebrate groups. Finally, we present a functional application of VSI to test a hypothesized relationship between body shape and the degree of axial bending associated with locomotor modes in ray-finned fishes. Altogether, our study highlights the promise VSI holds for identifying the morphological variation underlying body shape diversity as well as the selective factors driving shape evolution.

  14. Antibody Isotype Switching in Vertebrates.

    PubMed

    Senger, Kate; Hackney, Jason; Payandeh, Jian; Zarrin, Ali A

    2015-01-01

    The humoral or antibody-mediated immune response in vertebrates has evolved to respond to diverse antigenic challenges in various anatomical locations. Diversification of the immunoglobulin heavy chain (IgH) constant region via isotype switching allows for remarkable plasticity in the immune response, including versatile tissue distribution, Fc receptor binding, and complement fixation. This enables antibody molecules to exert various biological functions while maintaining antigen-binding specificity. Different immunoglobulin (Ig) classes include IgM, IgD, IgG, IgE, and IgA, which exist as surface-bound and secreted forms. High-affinity autoantibodies are associated with various autoimmune diseases such as lupus and arthritis, while defects in components of isotype switching are associated with infections. A major route of infection used by a large number of pathogens is invasion of mucosal surfaces within the respiratory, digestive, or urinary tract. Most infections of this nature are initially limited by effector mechanisms such as secretory IgA antibodies. Mucosal surfaces have been proposed as a major site for the genesis of adaptive immune responses, not just in fighting infections but also in tolerating commensals and constant dietary antigens. We will discuss the evolution of isotype switching in various species and provide an overview of the function of various isotypes with a focus on IgA, which is universally important in gut homeostasis as well as pathogen clearance. Finally, we will discuss the utility of antibodies as therapeutic modalities.

  15. Vertebral numbers and human evolution.

    PubMed

    Williams, Scott A; Middleton, Emily R; Villamil, Catalina I; Shattuck, Milena R

    2016-01-01

    Ever since Tyson (1699), anatomists have noted and compared differences in the regional numbers of vertebrae among humans and other hominoids. Subsequent workers interpreted these differences in phylogenetic, functional, and behavioral frameworks and speculated on the history of vertebral numbers during human evolution. Even in a modern phylogenetic framework and with greatly expanded sample sizes of hominoid species, researchers' conclusions vary drastically, positing that hominins evolved from either a "long-backed" (numerically long lumbar column) or a "short-backed" (numerically short lumbar column) ancestor. We show that these disparate interpretations are due in part to the use of different criteria for what defines a lumbar vertebra, but argue that, regardless of which lumbar definition is used, hominins are similar to their great ape relatives in possessing a short trunk, a rare occurrence in mammals and one that defines the clade Hominoidea. Furthermore, we address the recent claim that the early hominin thoracolumbar configuration is not distinct from that of modern humans and conclude that early hominins show evidence of "cranial shifting," which might explain the anomalous morphology of several early hominin fossils. Finally, we evaluate the competing hypotheses on numbers of vertebrae and argue that the current data support a hominin ancestor with an African ape-like short trunk and lower back. © 2016 Wiley Periodicals, Inc.

  16. Behavioral fever in ectothermic vertebrates.

    PubMed

    Rakus, Krzysztof; Ronsmans, Maygane; Vanderplasschen, Alain

    2017-01-01

    Fever is an evolutionary conserved defense mechanism which is present in both endothermic and ectothermic vertebrates. Ectotherms in response to infection can increase their body temperature by moving to warmer places. This process is known as behavioral fever. In this review, we summarize the current knowledge on the mechanisms of induction of fever in mammals. We further discuss the evolutionary conserved mechanisms existing between fever of mammals and behavioral fever of ectothermic vertebrates. Finally, the experimental evidences supporting an adaptive value of behavioral fever expressed by ectothermic vertebrates are summarized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Mitotic chromosome condensation in vertebrates

    SciTech Connect

    Vagnarelli, Paola

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes of

  18. Evolution of vertebrate sex chromosomes and dosage compensation.

    PubMed

    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.

  19. Transposable elements and vertebrate protein diversity.

    PubMed

    Lorenc, Anna; Makałowski, Wojciech

    2003-07-01

    Interspersed repetitive sequences are major components of eukaryotic genomes. Repetitive elements comprise about 50% of the mammalian genome. They interact with the whole genome and influence its evolution. Repetitive elements may serve as recombination hot spots or acquire specific cellular functions such as RNA transcription control or become part of protein coding regions. The latter is a subject of presented analysis. We searched all currently available vertebrate protein sequences, including human proteome complement for the presence of transposable elements. It appears that insertion of TE-cassettes into open reading frames is a general phenomena. They can be found in all vertebrate lineages and originate in all types of transposable elements. It seems that genomes use those cassettes as 'ready to use' motifs in their evolutionary experiments. Most of TE-cassettes are used to create alternative forms of a message and usually the other form, without TE-cassette, is expressed in a cell. Tables listing vertebrate messages with TE-cassettes are available at http://warta.bio.psu.edu/ScrapYard/.

  20. Evolution of the vertebrate epididymis.

    PubMed

    Jones, R C

    1998-01-01

    This review examines the structure and function of the extratesticular sperm ducts of vertebrates in terms of their evolutionary development and adaptive significance. The primitive extratesticular duct system of Chondrichthyes is described as an example of the vertebrate archetype. Adaptations of the duct system in higher vertebrates have involved a loss of some structures and specialization of others. The duct system probably evolved as a homeostatic mechanism to facilitate fertilization and some embryological development under conditions protected from the external environment. However, it is argued that the ducts also play an important role in the competition between males to achieve paternity. In vertebrates that practise internal fertilization the ducts are involved in post-testicular maturation and storage of spermatozoa. The biological significance of post-testicular sperm maturation has not been resolved. By contrast, sperm storage is essential in most male vertebrates because of the slow rate of spermatogenesis, particularly in ectotherms. Sperm storage is also important in the competition between males for paternity as it enables a male to mate a 'partner' a number of times during an oestrus in order to reduce the prospect of being cuckolded by another male. The extent of sperm maturation and storage in the epididymis of particular vertebrates depends on the relative roles of the testis and its extragonadal ducts in the competition between males for paternity. These roles depend on a number of factors, including allometric limitations to testis size, metabolic rate and the development of endothermy, and the reproductive strategy of females of the species.

  1. Lymphatic regulation in nonmammalian vertebrates.

    PubMed

    Hedrick, Michael S; Hillman, Stanley S; Drewes, Robert C; Withers, Philip C

    2013-08-01

    All vertebrate animals share in common the production of lymph through net capillary filtration from their closed circulatory system into their tissues. The balance of forces responsible for net capillary filtration and lymph formation is described by the Starling equation, but additional factors such as vascular and interstitial compliance, which vary markedly among vertebrates, also have a significant impact on rates of lymph formation. Why vertebrates show extreme variability in rates of lymph formation and how nonmammalian vertebrates maintain plasma volume homeostasis is unclear. This gap hampers our understanding of the evolution of the lymphatic system and its interaction with the cardiovascular system. The evolutionary origin of the vertebrate lymphatic system is not clear, but recent advances suggest common developmental factors for lymphangiogenesis in teleost fishes, amphibians, and mammals with some significant changes in the water-land transition. The lymphatic system of anuran amphibians is characterized by large lymphatic sacs and two pairs of lymph hearts that return lymph into the venous circulation but no lymph vessels per se. The lymphatic systems of reptiles and some birds have lymph hearts, and both groups have extensive lymph vessels, but their functional role in both lymph movement and plasma volume homeostasis is almost completely unknown. The purpose of this review is to present an evolutionary perspective in how different vertebrates have solved the common problem of the inevitable formation of lymph from their closed circulatory systems and to point out the many gaps in our knowledge of this evolutionary progression.

  2. [A vertebral arteriovenous fistula diagnosed by auscultation].

    PubMed

    Iglesias Escalera, G; Diaz-Delgado Peñas, R; Carrasco Marina, M Ll; Maraña Perez, A; Ialeggio, D

    2015-01-01

    Cervical artery fistulas are rare arteriovenous malformations. The etiology of the vertebral arteriovenous fistulas (AVF) can be traumatic or spontaneous. They tend to be asymptomatic or palpation or continuous vibration in the cervical region. An arteriography is necessary for a definitive diagnosis. The treatment is complete embolization of the fistula. We present the case of a two year-old male, where the mother described it «like a washing machine in his head». On palpation during the physical examination, there was a continuous vibration, and a continuous murmur in left cervical region. A vascular malformation in vertebral region was clinically suspected, and confirmed with angio-MRI and arteriography. AVF are rare in childhood. They should be suspected in the presence of noises, palpation or continuous vibration in the cervical region. Early diagnosis can prevent severe complications in asymptomatic children. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  3. Recombination Drives Vertebrate Genome Contraction

    PubMed Central

    Nam, Kiwoong; Ellegren, Hans

    2012-01-01

    Selective and/or neutral processes may govern variation in DNA content and, ultimately, genome size. The observation in several organisms of a negative correlation between recombination rate and intron size could be compatible with a neutral model in which recombination is mutagenic for length changes. We used whole-genome data on small insertions and deletions within transposable elements from chicken and zebra finch to demonstrate clear links between recombination rate and a number of attributes of reduced DNA content. Recombination rate was negatively correlated with the length of introns, transposable elements, and intergenic spacer and with the rate of short insertions. Importantly, it was positively correlated with gene density, the rate of short deletions, the deletion bias, and the net change in sequence length. All these observations point at a pattern of more condensed genome structure in regions of high recombination. Based on the observed rates of small insertions and deletions and assuming that these rates are representative for the whole genome, we estimate that the genome of the most recent common ancestor of birds and lizards has lost nearly 20% of its DNA content up until the present. Expansion of transposable elements can counteract the effect of deletions in an equilibrium mutation model; however, since the activity of transposable elements has been low in the avian lineage, the deletion bias is likely to have had a significant effect on genome size evolution in dinosaurs and birds, contributing to the maintenance of a small genome. We also demonstrate that most of the observed correlations between recombination rate and genome contraction parameters are seen in the human genome, including for segregating indel polymorphisms. Our data are compatible with a neutral model in which recombination drives vertebrate genome size evolution and gives no direct support for a role of natural selection in this process. PMID:22570634

  4. Automatic vertebral identification using surface-based registration

    NASA Astrophysics Data System (ADS)

    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.

  5. Independent regulation of vertebral number and vertebral identity by microRNA-196 paralogs

    PubMed Central

    Wong, Siew Fen Lisa; Agarwal, Vikram; Mansfield, Jennifer H.; Denans, Nicolas; Schwartz, Matthew G.; Prosser, Haydn M.; Pourquié, Olivier; Bartel, David P.; Tabin, Clifford J.; McGlinn, Edwina

    2015-01-01

    The Hox genes play a central role in patterning the embryonic anterior-to-posterior axis. An important function of Hox activity in vertebrates is the specification of different vertebral morphologies, with an additional role in axis elongation emerging. The miR-196 family of microRNAs (miRNAs) are predicted to extensively target Hox 3′ UTRs, although the full extent to which miR-196 regulates Hox expression dynamics and influences mammalian development remains to be elucidated. Here we used an extensive allelic series of mouse knockouts to show that the miR-196 family of miRNAs is essential both for properly patterning vertebral identity at different axial levels and for modulating the total number of vertebrae. All three miR-196 paralogs, 196a1, 196a2, and 196b, act redundantly to pattern the midthoracic region, whereas 196a2 and 196b have an additive role in controlling the number of rib-bearing vertebra and positioning of the sacrum. Independent of this, 196a1, 196a2, and 196b act redundantly to constrain total vertebral number. Loss of miR-196 leads to a collective up-regulation of numerous trunk Hox target genes with a concomitant delay in activation of caudal Hox genes, which are proposed to signal the end of axis extension. Additionally, we identified altered molecular signatures associated with the Wnt, Fgf, and Notch/segmentation pathways and demonstrate that miR-196 has the potential to regulate Wnt activity by multiple mechanisms. By feeding into, and thereby integrating, multiple genetic networks controlling vertebral number and identity, miR-196 is a critical player defining axial formulae. PMID:26283362

  6. Bone densitometry in the diagnosis of vertebral fractures in children: accuracy of vertebral fracture assessment.

    PubMed

    Mäyränpää, Mervi K; Helenius, Ilkka; Valta, Helena; Mäyränpää, Mikko I; Toiviainen-Salo, Sanna; Mäkitie, Outi

    2007-09-01

    DXA scanner derived images of the spine are used for vertebral fracture detection in adults. It is unknown whether the method could be used in pediatrics. This study evaluated the diagnostic accuracy of DXA images in vertebral fracture assessment (VFA) in children. The study included 65 children (37 males; median age 12.1 years) with primary or secondary osteoporosis. Data on clinical history were collected from hospital records. Patients were assessed for spinal compression fractures by standard spinal radiographs and by bone densitometry (Hologic Discovery A) derived VFA images. The visibility and morphology of each vertebra in VFA images was assessed by two readers and by a semi-computerized software developed for the DXA scanner. The findings were compared with those in spinal radiographs and correlated with clinical parameters. The visibility of vertebrae in VFA images was good in T8-L4 but compromised in the upper thoracic region (T4-T7) and was constantly inferior to that in standard radiographs. A total of 25 vertebral fractures were diagnosed in radiographs, but only 9 (36%) of these also in VFA images. The semi-computerized software could not accurately detect vertebrae in most of the children; accuracy increased with increasing age, height and BMD but was not sufficient to detect vertebral fractures. The utility of DXA scanner derived images of the spine in vertebral fracture detection in children is limited by compromised visibility and poor diagnostic accuracy. The semi-computerized software is not suitable for pediatric use. These limitations should be kept in mind when assessing pediatric patients for osteoporosis.

  7. [Neural crest and vertebrate evolution].

    PubMed

    Le Douarin, Nicole M; Creuzet, Sophie

    2011-01-01

    The neural crest (NC) is a remarkable structure of the Vertebrate embryo, which forms from the lateral borders of the neural plate (designated as neural folds) during neural tube closure. As soon as the NC is formed, its constitutive cells detach and migrate away from the neural primordium along definite pathways and at precise periods of time according to a rostro-caudal progression. The NC cells aggregate in definite places in the developing embryo, where they differentiate into a large variety of cell types including the neurons and glial cells of the peripheral nervous system, the pigment cells dispersed throughout the body and endocrine cells such as the adrenal medulla and the calcitonin producing cells. At the cephalic level only, in higher Vertebrates (but along the whole neural axis in Fishes and Amphibians), the NC is also at the origin of mesenchymal cells differentiating into connective tissue chondrogenic and osteogenic cells. Vertebrates belong to the larger group of Cordates which includes also the Protocordates (Cephalocordates and the Urocordates). All Cordates are characterized by the same body plan with a dorsal neural tube and a notochord which, in Vertebrates, exists only at embryonic stages. The main difference between Protocordates and Vertebrates is the very rudimentary development of cephalic structures in the former. As a result, the process of cephalization is one of the most obvious characteristics of Vertebrates. It was accompanied by the apparition of the NC which can therefore be considered as an innovation of Vertebrates during evolution. The application of a cell marking technique which consists in constructing chimeric embryos between two species of birds, the quail and the chicken, has led to show that the vertebrate head is mainly formed by cells originating from the NC, meaning that this structure was an important asset in Vertebrate evolution. Recent studies, described in this article, have strengthened this view by showing

  8. [Serine proteinases of lower vertebrates].

    PubMed

    Kolodzeĭskaia, M V

    1986-01-01

    Recent data on the effect of serine proteinases of lower vertebrates are generalized. Hydrolysis specificity and kinetics of different synthetic substrates, dependence of the activity of enzymes on pH, their irreversible inhibition by chloromethyl ketones of amino acids and peptides as well as high-molecular proteinase inhibitors are considered in detail. The data testify to the fact that chymotrypsins and trypsins of higher vertebrates and serine proteinases of lower vertebrates act as an acid-base catalysis. Enzymes in the pyloric cacca of fishes are in the state of proenzymes and are transformed into an active form with the aid of their own proteolytic factors. The esterase and proteolytic activity of fish proteinases is concentrated in the same active site and reaches the highest values at pH 7,8. New data are presented on particularities of the lower vertebrate proteinases, on the similarity and differences in their specificity. A distinct difference is shown in the nature of the binding site of the active centre in a number of serine proteinases of fishes as compared to chymotrypsin and trypsin of higher vertebrates.

  9. Three periods of regulatory innovation during vertebrate evolution.

    PubMed

    Lowe, Craig B; Kellis, Manolis; Siepel, Adam; Raney, Brian J; Clamp, Michele; Salama, Sofie R; Kingsley, David M; Lindblad-Toh, Kerstin; Haussler, David

    2011-08-19

    The gain, loss, and modification of gene regulatory elements may underlie a substantial proportion of phenotypic changes on animal lineages. To investigate the gain of regulatory elements throughout vertebrate evolution, we identified genome-wide sets of putative regulatory regions for five vertebrates, including humans. These putative regulatory regions are conserved nonexonic elements (CNEEs), which are evolutionarily conserved yet do not overlap any coding or noncoding mature transcript. We then inferred the branch on which each CNEE came under selective constraint. Our analysis identified three extended periods in the evolution of gene regulatory elements. Early vertebrate evolution was characterized by regulatory gains near transcription factors and developmental genes, but this trend was replaced by innovations near extracellular signaling genes, and then innovations near posttranslational protein modifiers.

  10. Vestibular blueprint in early vertebrates

    PubMed Central

    Straka, Hans; Baker, Robert

    2013-01-01

    Central vestibular neurons form identifiable subgroups within the boundaries of classically outlined octavolateral nuclei in primitive vertebrates that are distinct from those processing lateral line, electrosensory, and auditory signals. Each vestibular subgroup exhibits a particular morpho-physiological property that receives origin-specific sensory inputs from semicircular canal and otolith organs. Behaviorally characterized phenotypes send discrete axonal projections to extraocular, spinal, and cerebellar targets including other ipsi- and contralateral vestibular nuclei. The anatomical locations of vestibuloocular and vestibulospinal neurons correlate with genetically defined hindbrain compartments that are well conserved throughout vertebrate evolution though some variability exists in fossil and extant vertebrate species. The different vestibular subgroups exhibit a robust sensorimotor signal processing complemented with a high degree of vestibular and visual adaptive plasticity. PMID:24312016

  11. Learning about Vertebrate Limb Development

    ERIC Educational Resources Information Center

    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…

  12. Learning about Vertebrate Limb Development

    ERIC Educational Resources Information Center

    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…

  13. Vertebrate Embryonic Cleavage Pattern Determination.

    PubMed

    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.

  14. The ISCD and Vertebral Fractures.

    PubMed

    Vokes, Tamara; Lentle, Brian

    2016-01-01

    Some 30 years ago the diagnosis of osteoporosis relied primarily on the measurement of bone mineral density by DXA. More recently, however, it was recognized that vertebral fractures are an important predictor of future fractures and that they reflect some aspect of bone fragility not captured by BMD measurement. In response to that, DXA manufacturers developed VFA, spine imaging on the densitometer, which allowed integration of BMD with information on vertebral fractures obtained at the same visit. ISCD has been instrumental in several aspects of VFA use such as developing and teaching courses for VFA or more broadly, for recognition of vertebral fractures; in developing guidelines for performance, interpretation and reporting of the VFA; and in advocating for reimbursement for VFA tests performed in the clinical practice. ISCD is poised to continue as a leader in vertebral fracture recognition and application of VFA to clinical practice and research. Copyright © 2016 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  15. Symptomatic vertebral hemangiomas during pregnancy.

    PubMed

    Moles, Alexis; Hamel, Olivier; Perret, Christophe; Bord, Eric; Robert, Roger; Buffenoir, Kevin

    2014-05-01

    Symptomatic vertebral hemangiomas during pregnancy are rare, as only 27 cases have been reported in the literature since 1948. However, symptomatic vertebral hemangiomas can be responsible for spinal cord compression, in which case they constitute a medical emergency, which raises management difficulties in the context of pregnancy. Pregnancy is a known factor responsible for deterioration of these vascular tumors. In this paper, the authors report 2 clinical cases of symptomatic vertebral hemangiomas during pregnancy, including 1 case of spontaneous fracture that has never been previously reported in the literature. The authors then present a brief review of the literature to discuss emergency management of this condition. The first case was a 28-year-old woman at 35 weeks of gestation, who presented with paraparesis. Spinal cord MRI demonstrated a vertebral hemangioma invading the body and posterior arch of T-3 with posterior epidural extension. Laminectomy and vertebroplasty were performed after cesarean section, allowing neurological recovery. The second case involved a 35-year-old woman who presented with spontaneous fracture of T-7 at 36 weeks of gestation, revealing a vertebral hemangioma with no neurological deficit, but it was responsible for pain and local instability. Treatment consisted of postpartum posterior interbody fusion. With a clinical and radiological follow-up of 2 years, no complications and no modification of the hemangiomas were observed. A review of the literature reveals discordant management of these rare cases, which is why the treatment course must be decided by a multidisciplinary team as a function of fetal gestational age and maternal neurological features.

  16. Early development of the vertebral column.

    PubMed

    Scaal, Martin

    2016-01-01

    The segmental organization of the vertebrate body is most obviously visible in the vertebral column, which consists of a series of vertebral bones and interconnecting joints and ligaments. During embryogenesis, the vertebral column derives from the somites, which are the primary segments of the embryonic paraxial mesoderm. Anatomical, cellular and molecular aspects of vertebral column development have been of interest to developmental biologists for more than 150 years. This review briefly summarizes the present knowledge on early steps of vertebral column development in amniotes, starting from sclerotome formation and leading to the establishment of the anatomical bauplan of the spine composed of vertebral bodies, vertebral arches, intervertebral discs and ribs, and their specific axial identities along the body axis.

  17. Lumbo-Costo-Vertebral Syndrome with Congenital Lumbar Hernia

    PubMed Central

    Gupta, Lucky; 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. PMID:24834386

  18. Evolution of endothelin receptors in vertebrates.

    PubMed

    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

  19. Vertebral bending mechanics and xenarthrous morphology in the nine-banded armadillo (Dasypus novemcinctus).

    PubMed

    Oliver, Jillian D; Jones, Katrina E; Hautier, Lionel; Loughry, W J; Pierce, Stephanie E

    2016-10-01

    The vertebral column has evolved to accommodate the broad range of locomotor pressures found across vertebrate lineages. Xenarthran (armadillos, sloths and anteaters) vertebral columns are characterized by xenarthrous articulations, novel intervertebral articulations located in the posterior trunk that are hypothesized to stiffen the vertebral column to facilitate digging. To determine the degree to which xenarthrous articulations impact vertebral movement, we passively measured compliance and range of motion during ventroflexion, dorsiflexion and lateral bending across the thoracolumbar region of the nine-banded armadillo, Dasypus novemcinctus Patterns of bending were compared with changes in vertebral morphology along the column to determine which morphological features best predict intervertebral joint mechanics. We found that compliance was lower in post-diaphragmatic, xenarthrous vertebrae relative to pre-xenarthrous vertebrae in both sagittal and lateral planes of bending. However, we also found that range of motion was higher in this region. These changes in mechanics are correlated with the transition from pre-xenarthrous to xenarthrous vertebrae, as well as with the transition from thoracic to lumbar vertebrae. Our results thus substantiate the hypothesis that xenarthrous articulations stiffen the vertebral column. Additionally, our data suggest that xenarthrous articulations, and their associated enlarged metapophyses, also act to increase the range of motion of the post-diaphragmatic region. We propose that xenarthrous articulations perform the dual role of stiffening the vertebral column and increasing mobility, resulting in passively stable vertebrae that are capable of substantial bending under appropriate loads. © 2016. Published by The Company of Biologists Ltd.

  20. Evolution and Diversity of Transposable Elements in Vertebrate Genomes

    PubMed Central

    Sotero-Caio, Cibele G.; Platt, Roy N.; Suh, Alexander

    2017-01-01

    Transposable elements (TEs) are selfish genetic elements that mobilize in genomes via transposition or retrotransposition and often make up large fractions of vertebrate genomes. Here, we review the current understanding of vertebrate TE diversity and evolution in the context of recent advances in genome sequencing and assembly techniques. TEs make up 4–60% of assembled vertebrate genomes, and deeply branching lineages such as ray-finned fishes and amphibians generally exhibit a higher TE diversity than the more recent radiations of birds and mammals. Furthermore, the list of taxa with exceptional TE landscapes is growing. We emphasize that the current bottleneck in genome analyses lies in the proper annotation of TEs and provide examples where superficial analyses led to misleading conclusions about genome evolution. Finally, recent advances in long-read sequencing will soon permit access to TE-rich genomic regions that previously resisted assembly including the gigantic, TE-rich genomes of salamanders and lungfishes. PMID:28158585

  1. Active DNA demethylation at enhancers during the vertebrate phylotypic period.

    PubMed

    Bogdanović, Ozren; Smits, Arne H; de la Calle Mustienes, Elisa; Tena, Juan J; Ford, Ethan; Williams, Ruth; Senanayake, Upeka; Schultz, Matthew D; Hontelez, Saartje; van Kruijsbergen, Ila; Rayon, Teresa; Gnerlich, Felix; Carell, Thomas; Veenstra, Gert Jan C; Manzanares, Miguel; Sauka-Spengler, Tatjana; Ecker, Joseph R; Vermeulen, Michiel; Gómez-Skarmeta, José Luis; Lister, Ryan

    2016-04-01

    The vertebrate body plan and organs are shaped during a conserved embryonic phase called the phylotypic stage. However, the mechanisms that guide the epigenome through this transition and their evolutionary conservation remain elusive. Here we report widespread DNA demethylation of enhancers during the phylotypic period in zebrafish, Xenopus tropicalis and mouse. These enhancers are linked to developmental genes that display coordinated transcriptional and epigenomic changes in the diverse vertebrates during embryogenesis. Binding of Tet proteins to (hydroxy)methylated DNA and enrichment of 5-hydroxymethylcytosine in these regions implicated active DNA demethylation in this process. Furthermore, loss of function of Tet1, Tet2 and Tet3 in zebrafish reduced chromatin accessibility and increased methylation levels specifically at these enhancers, indicative of DNA methylation being an upstream regulator of phylotypic enhancer function. Overall, our study highlights a regulatory module associated with the most conserved phase of vertebrate embryogenesis and suggests an ancient developmental role for Tet dioxygenases.

  2. Vertebral Augmentation for Osteoporotic Compression Fractures.

    PubMed

    Richmond, Bradford J

    2016-01-01

    Vertebral augmentation procedures such as vertebroplasty and kyphoplasty were developed to reduce pain and improve quality of life for patients with osteoporotic vertebral compression fractures. However, the use of vertebral augmentation has been debated and questioned since its inception. This article addresses some of these issues.

  3. Cervical vertebral bone age in girls.

    PubMed

    Mito, Toshinori; Sato, Koshi; Mitani, Hideo

    2002-10-01

    The purpose of this study was to establish cervical vertebral bone age as a new index for objectively evaluating skeletal maturation on cephalometric radiographs. Using cephalometric radiographs of 176 girls (ages 7.0-14.9 years), we measured cervical vertebral bodies and determined a regression formula to obtain cervical vertebral bone age. Next, using cephalometric and hand-wrist radiographs of another 66 girls (ages 8.0-13.9 years), we determined the correlation between cervical vertebral bone age and bone age using the Tanner-Whitehouse 2 method. The following results were obtained: (1) a regression formula was determined to obtain cervical vertebral bone age based on ratios of measurements in the third and fourth cervical vertebral bodies; (2) the correlation coefficient for the relationship between cervical vertebral bone age and bone age (0.869) was significantly (P <.05) higher than that for the relationship between cervical vertebral bone age and chronological age (0.705); and (3) the difference (absolute value) between the cervical vertebral bone age and bone age (0.75 years) was significantly (P <.001) smaller than that between cervical vertebral bone age and chronological age (1.17 years). These results suggest that cervical vertebral bone age reflects skeletal maturity because it approximates bone age, which is considered to be the most reliable method for evaluating skeletal maturation. Using cervical vertebral bone age, it might be possible to evaluate maturity in a detailed and objective manner on cephalometric radiographs.

  4. An extensive vertebral hydatidosis revealed by a lumbosciatica.

    PubMed

    Rkain, H; Bahiri, R; Benbouazza, K; Hajjaj-Hassouni, N

    2007-08-01

    The vertebral hydatidosis is uncommon. It causes problems in diagnosis and in management. A case of an extensive vertebral hydatidosis with few symptoms is reported. A 21-year-old man has consulted for recurrent lumbosciatica that has been evolving for 1 year. Clinical exam was normal. Plain radiographic films disclosed a lytic lesion throughout the bodies of L4 and L5 and calcifications thrown on the liver area. The computed tomography (CT) and the magnetic resonance (MR) images revealed multicystic bony lesions involving the lumbar spine with extension into the spinal canal. Abdominal ultrasound showed also cyst lesions in the right kidney and in the liver. The diagnosis of vertebral and abdominal (liver and kidney) hydatidosis was retained. Four sets of 4-week albendazole cures were given with a 2-week interval in between. Our case of extended vertebral hydatidosis with few symptoms confirms the clinical latency and diagnosis difficulties usually encountered in this disease. This often leads to a late diagnosis of the stage of spinal cord compression. Radiological diagnosis and determination of extension of the hydatid cyst are usually provided by CT and MRI. Vertebral hydatidosis should be evoked in lumbosciatica especially in endemic regions.

  5. The common ancestral core of vertebrate and fungal telomerase RNAs

    PubMed Central

    Qi, Xiaodong; Li, Yang; Honda, Shinji; Hoffmann, Steve; Marz, Manja; Mosig, Axel; Podlevsky, Joshua D.; Stadler, Peter F.; Selker, Eric U.; Chen, Julian J.-L.

    2013-01-01

    Telomerase is a ribonucleoprotein with an intrinsic telomerase RNA (TER) component. Within yeasts, TER is remarkably large and presents little similarity in secondary structure to vertebrate or ciliate TERs. To better understand the evolution of fungal telomerase, we identified 74 TERs from Pezizomycotina and Taphrinomycotina subphyla, sister clades to budding yeasts. We initially identified TER from Neurospora crassa using a novel deep-sequencing–based approach, and homologous TER sequences from available fungal genome databases by computational searches. Remarkably, TERs from these non-yeast fungi have many attributes in common with vertebrate TERs. Comparative phylogenetic analysis of highly conserved regions within Pezizomycotina TERs revealed two core domains nearly identical in secondary structure to the pseudoknot and CR4/5 within vertebrate TERs. We then analyzed N. crassa and Schizosaccharomyces pombe telomerase reconstituted in vitro, and showed that the two RNA core domains in both systems can reconstitute activity in trans as two separate RNA fragments. Furthermore, the primer-extension pulse-chase analysis affirmed that the reconstituted N. crassa telomerase synthesizes TTAGGG repeats with high processivity, a common attribute of vertebrate telomerase. Overall, this study reveals the common ancestral cores of vertebrate and fungal TERs, and provides insights into the molecular evolution of fungal TER structure and function. PMID:23093598

  6. Segment Identity and Cell Segregation in the Vertebrate Hindbrain.

    PubMed

    Addison, Megan; Wilkinson, David G

    2016-01-01

    The subdivision of tissues into sharply demarcated regions with distinct and homogenous identity is an essential aspect of embryonic development. Along the anteroposterior axis of the vertebrate nervous system, this involves signaling which induces spatially restricted expression of transcription factors that specify regional identity. The spatial expression of such transcription factors is initially imprecise, with overlapping expression of genes that specify distinct identities, and a ragged border at the interface of adjacent regions. This pattern becomes sharpened by establishment of mutually exclusive expression of transcription factors, and by cell segregation that underlies formation of a straight border. In this review, we discuss studies of the vertebrate hindbrain which have revealed how discrete regional identity is established, the roles of Eph-ephrin signaling in cell segregation and border sharpening, and how cell identity and cell segregation are coupled. © 2016 Elsevier Inc. All rights reserved.

  7. Globalisation reaches gene regulation: the case for vertebrate limb development.

    PubMed

    Zuniga, Aimée

    2005-08-01

    Analysis of key regulators of vertebrate limb development has revealed that the cis-regulatory regions controlling their expression are often located several hundred kilobases upstream of the transcription units. These far up- or down-stream cis-regulatory regions tend to reside within rather large, functionally and structurally unrelated genes. Molecular analysis is beginning to reveal the complexity of these large genomic landscapes, which control the co-expression of clusters of diverse genes by this novel type of long-range and globally acting cis-regulatory region. An increasing number of spontaneous mutations in vertebrates, including humans, are being discovered inactivating or altering such global control regions. Thereby, the functions of a seemingly distant but essential gene are disrupted rather than the closest.

  8. Morphological castes in a vertebrate

    PubMed Central

    O'Riain, M. J.; Jarvis, J. U. M.; Alexander, R.; Buffenstein, R.; Peeters, C.

    2000-01-01

    Morphological specialization for a specific role has, until now, been assumed to be restricted to social invertebrates. Herein we show that complete physical dimorphism has evolved between reproductives and helpers in the eusocial naked mole-rat. Dimorphism is a consequence of the lumbar vertebrae lengthening after the onset of reproduction in females. This is the only known example of morphological castes in a vertebrate and is distinct from continuous size variation between breeders and helpers in other species of cooperatively breeding vertebrates. The evolution of castes in a mammal and insects represents a striking example of convergent evolution for enhanced fecundity in societies characterized by high reproductive skew. Similarities in the selective environment between naked mole-rats and eusocial insect species highlight the selective conditions under which queen/worker castes are predicted to evolve in animal societies. PMID:11087866

  9. Vertebral osteomyelitis complicated by iliopsoas muscle abscess in an immunocompetent adolescent: successful conservative treatment.

    PubMed

    Wu, Shun-Yao; Wei, Ta-Sen; Chen, Yen-Chun; Huang, Shih-Wei

    2012-10-01

    Vertebral osteomyelitis is rare in children. The lumbar spine is the most commonly involved region. Vertebral osteomyelitis occurs more frequently in the vertebral body, and involvement of posterior element is rare. Vertebral osteomyelitis results from hematogenous seeding, spread from contiguous infections, and direct inoculation from spinal surgery. Initial symptoms include low back pain, difficulty standing, limping gait, and fever. Blood cultures should be obtained for children with vertebral osteomyelitis because it is the definite guide for providing accurate treatment. Computed tomographyi-guided abscess aspiration should be considered for patients with negative blood cultures. Staphylococcus aureus is the most common microorganism in vertebral osteomyelitis, and the incidence of methicillin-resistant S aureus has increased in recent years. Plain radiographs, bone scintigraphy, and magnetic resonance imaging are useful for making the diagnosis. Antimicrobial therapy for 6 weeks is usually successful, and an early transition to oral form does not increase the risk of treatment failure. Debridement with implant removal is required, especially for late-onset infections associated with previous spinal surgery. Vertebral osteomyelitis can cause motor weakness and paralysis. Because of the involvement of spinal development, spinal deformities, including scoliosis and loss of normal lumbar lordosis, should be a concern in pediatric patients. Early diagnosis and adequate treatment for vertebral osteomyelitis are important to prevent severe complications and lifelong disabilities.This article describes the case of a 14-year-old boy with spontaneous lumbar vertebral osteomyelitis who initially presented with low back pain and was successfully treated nonoperatively.

  10. Vertebral development and amphibian evolution.

    PubMed

    Carroll, R L; Kuntz, A; Albright, K

    1999-01-01

    Amphibians provide an unparalleled opportunity to integrate studies of development and evolution through the investigation of the fossil record of larval stages. The pattern of vertebral development in modern frogs strongly resembles that of Paleozoic labyrinthodonts in the great delay in the ossification of the vertebrae, with the centra forming much later than the neural arches. Slow ossification of the trunk vertebrae in frogs and the absence of ossification in the tail facilitate the rapid loss of the tail during metamorphosis, and may reflect retention of the pattern in their specific Paleozoic ancestors. Salamanders and caecilians ossify their centra at a much earlier stage than frogs, which resembles the condition in Paleozoic lepospondyls. The clearly distinct patterns and rates of vertebral development may indicate phylogenetic separation between the ultimate ancestors of frogs and those of salamanders and caecilians within the early radiation of ancestral tetrapods. This divergence may date from the Lower Carboniferous. Comparison with the molecular regulation of vertebral development described in modern mammals and birds suggests that the rapid chondrification of the centra in salamanders relative to that of frogs may result from the earlier migration of sclerotomal cells expressing Pax1 to the area surrounding the notochord.

  11. Trabecular Microstructure and Damage Affect Cement Leakage From the Basivertebral Foramen During Vertebral Augmentation.

    PubMed

    Li, Shengyun; Wang, Chongyan; Shan, Zhi; Liu, Junhui; Yu, Tianming; Zhang, Xuyang; Fan, Shunwu; Christiansen, Blaine A; Ding, Wenyuan; Zhao, Fengdong

    2017-08-15

    A prospective study on cadaver specimens. To explore why cement leakage from basivertebral foramen (BF) easily occurs during vertebral augmentation procedures. Type B (through BF, basivertebral foramen) cement leakage is the most common type after vertebral augmentation, but the mechanism of this is still controversial. The contribution of vertebral trabecular bone orientation and trabecular damage during compression fracture to cement leakage is still unknown. In this study, 12 fresh-frozen human lumbar spines (T12-L5) were collected and divided into 24 three-segment units. Mechanical testing was performed to simulate a compression fracture. MicroCT were performed on all segments before and after mechanical testing, and trabecular microstructure of the superior, middle (containing BF), and inferior 1/3 of each vertebral body was analyzed. The diameter variation of intertrabecular space before and after compression fracture was used to quantify trabecular injury. After mechanical testing, vertebral augmentation, and imaging-based diagnosis were used to evaluate cement leakage. Trabecular bone microstructural parameters in middle region (containing BF) were lower than those of the superior or inferior regions (P < 0.01). After compressive failure, 3D-reconstruction of the vertebral body by MicroCT demonstrated that intertrabecular distance in the middle region was markedly increased. Type B cement leakage was the most common type after vertebral augmentation, as found previously in Wang et al. (Spine J 2014;14: 1551-1558). The presence of the BF and the relative sparsity of trabecular bone make the middle region of the vertebral body the mechanically weakest region. Trabecular bone in middle region suffered the most severe damage during compressive failure of the vertebral body, which resulted in the greatest intervertebral spacing, and subsequently the highest percentage of type B cement leakage. These data suggest specific mechanisms by which cement may leak

  12. Ewing's sarcoma of the vertebral column

    SciTech Connect

    Pilepich, M.V.; Vietti, T.J.; Nesbit, M.E.; Tefft, M.; Kissane, J.; Burgert, O.; Pritchard, D.; Gehan, E.A.

    1981-01-01

    Twenty-two patients with vertebral primaries were registered in the Intergroup Ewing's Sarcoma Study between 1973 and 1977. The radiation doses to the primary tumors ranged between 3800 and 6200 rad. All patients received intensive combination chemotherapy. After a followup ranging between 14 and 62 months, 14 patients remained disease-free. All patients with primary tumor of the cervical and dorsal spine remained disease-free. Of eight patients with lesions in the distal spine, (sacrococcygeal region) six developed recurrence, in three a local recurrence was observed despite doses of 6000 rad or higher. Doses of 5000 rad or less (in addition to combination chemotherapy as used in the Intergroup Ewing's Study) appear adequate in controlling the primary tumors of the proximal segments of the spinal column.

  13. Global patterns in threats to vertebrates by biological invasions

    PubMed Central

    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

  14. Global patterns in threats to vertebrates by biological invasions.

    PubMed

    Bellard, C; Genovesi, P; Jeschke, J M

    2016-01-27

    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.

  15. Asymmetry in the epithalamus of vertebrates

    PubMed Central

    L. CONCHA, MIGUEL; W. WILSON, STEPHEN

    2001-01-01

    The epithalamus is a major subdivision of the diencephalon constituted by the habenular nuclei and pineal complex. Structural asymmetries in this region are widespread amongst vertebrates and involve differences in size, neuronal organisation, neurochemistry and connectivity. In species that possess a photoreceptive parapineal organ, this structure projects asymmetrically to the left habenula, and in teleosts it is also situated on the left side of the brain. Asymmetries in size between the left and right sides of the habenula are often associated with asymmetries in neuronal organisation, although these two types of asymmetry follow different evolutionary courses. While the former is more conspicuous in fishes (with the exception of teleosts), asymmetries in neuronal organisation are more robust in amphibia and reptiles. Connectivity of the parapineal organ with the left habenula is not always coupled with asymmetries in habenular size and/or neuronal organisation suggesting that, at least in some species, assignment of parapineal and habenular asymmetries may be independent events. The evolutionary origins of epithalamic structures are uncertain but asymmetry in this region is likely to have existed at the origin of the vertebrate, perhaps even the chordate, lineage. In at least some extant vertebrate species, epithalamic asymmetries are established early in development, suggesting a genetic regulation of asymmetry. In some cases, epigenetic factors such as hormones also influence the development of sexually dimorphic habenular asymmetries. Although the genetic and developmental mechanisms by which neuroanatomical asymmetries are established remain obscure, some clues regarding the mechanisms underlying laterality decisions have recently come from studies in zebrafish. The Nodal signalling pathway regulates laterality by biasing an otherwise stochastic laterality decision to the left side of the epithalamus. This genetic mechanism ensures a consistency of

  16. Evolution of vertebrate colour vision.

    PubMed

    Jacobs, Gerald H; Rowe, Mickey P

    2004-07-01

    Recent years have witnessed a growing interest in learning how colour vision has evolved. This trend has been fuelled by an enhanced understanding of the nature and extent of colour vision among contemporary species, by a deeper understanding of the paleontological record and by the application of new tools from molecular biology. This review provides an assessment of the progress in understanding the evolution of vertebrate colour vision. In so doing, we offer accounts of the evolution of three classes of mechanism important for colour vision--photopigment opsins, oil droplets and retinal organisation--and then examine details of how colour vision has evolved among mammals and, more specifically, among primates.

  17. Evolution of vertebrate visual pigments.

    PubMed

    Bowmaker, James K

    2008-09-01

    The visual pigments of vertebrates evolved about 500 million years ago, before the major evolutionary step of the development of jaws. Four spectrally distinct classes of cone opsin evolved through gene duplication, followed by the rod opsin class that arose from the duplication of the middle-wave-sensitive cone opsin. All four cone classes are present in many extant teleost fish, reptiles and birds, but one or more classes have been lost in primitive fish, amphibians and mammals. Gene duplication within the cone classes, especially in teleosts, has resulted in multiple opsins being available, both temporally and spatially, during development.

  18. Early steps in vertebrate cardiogenesis.

    PubMed

    Mohun, T; Sparrow, D

    1997-10-01

    Heart formation provides an excellent model for studying the molecular basis of cell determination in vertebrate embryos. By combining molecular assays with the experimental approaches of classic embryology, a model for the cell signalling events that initiate cardiogenesis is emerging. Studies of chick, amphibian, and fish embryos demonstrate the inductive role of dorso-anterior endoderm in specifying the cardiac fate of adjacent mesoderm. A consequence of this signalling is the onset of cardiomyogenesis and several transcription factors--Nkx2-5-related, HAND, GATA and MEF-2 families--contribute to these events.

  19. Vertebral Artery Injury during Routine Posterior Cervical Exposure: Case Reports and Review of Literature

    PubMed Central

    Molinari, Robert W.; Chimenti, Peter C.; Molinari, Robert; Gruhn, William

    2015-01-01

    Study Design Case series. Objective We report the unusual occurrence of vertebral artery injury (VAI) during routine posterior exposure of the cervical spine. The importance of preoperative planning to identify the course of the bilateral vertebral arteries during routine posterior cervical spine surgery is emphasized. Methods VAI is a rare but potentially devastating complication of cervical spinal surgery. Most reports of VAI are related to anterior surgical exposure or screw placement in the posterior cervical spine. VAI incurred during posterior cervical spinal exposure surgery is not adequately addressed in the existing literature. Two cases of VAI that occurred during routine posterior exposure of the cervical spine in the region of C2 are described. Results VAI was incurred unexpectedly in the region of the midportion of the posterior C1–C2 interval during the initial surgical exposure phase of the operation. An aberrant vertebral artery course in the V2 anatomical section in the region between C1 and C2 intervals was identified postoperatively in both patients. A literature review demonstrates a relatively high incidence of vertebral artery anomalies in the upper cervical spine; however, the literature is deficient in reporting vertebral artery injury in this region. Recommendations for preoperative vertebral artery imaging also remain unclear at this time. Conclusions Successful management of this unexpected complication was achieved in both cases. This case report and review of the literature highlights the importance of preoperative vertebral artery imaging and knowledge of the course of the vertebral arteries prior to planned routine posterior exposure of the upper cervical spine. In both cases, aberrancy of the vertebral artery was present and not investigated or detected preoperatively. PMID:26682106

  20. [Spontaneous vertebral arteriovenous fistula manifestating as radiculopathy].

    PubMed

    Ito, Osamu; Nishimura, Ataru; Ishido, Katsuya; Hitotsumatsu, Tsutomu

    2011-08-01

    A 61-year-old man presented with a rare case of spontaneous vertebral arteriovenous fistula manifesting as radiculopathy of the left arm. MRI demonstrated an abnormal dilated vascular space on the left ventral aspect of the spinal canal and compression of the spinal cord and subarachnoid space. MRA disclosed a single high-flow vertebral arteriovenous fistula. Angiography showed a direct high-flow fistula at the C2-3 level between the left vertebral artery and the spinal extradural veinous plexus, and an abnormal dilated left vertebral artery with "string of beads"-like feature. The fistula was successfully obliterated by coil embolization with preservation of patency of the left vertebral artery, resulting in improvement of the signs and symptoms. Retrospectively this spontaneous vertebral arteriovenous fistula was considered in association with fibromuscular dysplasia.

  1. Evolutionary Specialization of Tactile Perception in Vertebrates.

    PubMed

    Schneider, Eve R; Gracheva, Elena O; Bagriantsev, Slav N

    2016-05-01

    Evolution has endowed vertebrates with the remarkable tactile ability to explore the world through the perception of physical force. Yet the sense of touch remains one of the least well understood senses at the cellular and molecular level. Vertebrates specializing in tactile perception can highlight general principles of mechanotransduction. Here, we review cellular and molecular adaptations that underlie the sense of touch in typical and acutely mechanosensitive vertebrates. ©2016 Int. Union Physiol. Sci./Am. Physiol. Soc.

  2. Evolutionary Specialization of Tactile Perception in Vertebrates

    PubMed Central

    Schneider, Eve R.

    2016-01-01

    Evolution has endowed vertebrates with the remarkable tactile ability to explore the world through the perception of physical force. Yet the sense of touch remains one of the least well understood senses at the cellular and molecular level. Vertebrates specializing in tactile perception can highlight general principles of mechanotransduction. Here, we review cellular and molecular adaptations that underlie the sense of touch in typical and acutely mechanosensitive vertebrates. PMID:27053733

  3. Endocrine disruption in aquatic vertebrates.

    PubMed

    Kloas, Werner; Urbatzka, Ralph; Opitz, Robert; Würtz, Sven; Behrends, Thomas; Hermelink, Björn; Hofmann, Frauke; Jagnytsch, Oana; Kroupova, Hana; Lorenz, Claudia; Neumann, Nadja; Pietsch, Constanze; Trubiroha, Achim; Van Ballegooy, Christoph; Wiedemann, Caterina; Lutz, Ilka

    2009-04-01

    Environmental compounds can interfere with endocrine systems of wildlife and humans. The main sink of such substances, called endocrine disrupters (ED), are surface waters. Thus, aquatic vertebrates, such as fish and amphibians, are most endangered. ED can adversely affect reproductive biology and the thyroid system. ED act by (anti)estrogenic and (anti)androgenic modes of action, resulting in abnormal sexual differentiation and impaired reproduction. These effects are mainly driven by direct interferences of ED with sex steroid receptors rather than indirectly by impacting synthesis and bioavailability of sex steroids, which in turn might affect the hypothalamic-pituitary-gonadal axis. Recent findings reveal that, in addition to the human-produced waste of ED, natural sources, such as parasites and decomposition of leaves, also might act as ED, markedly affecting sexual differentiation and reproduction in fish and amphibians. Although the thyroid system has essential functions in both fish and amphibians, amphibian metamorphosis has been introduced as the most sensitive model to detect thyroidal ED; no suitable fish model exists. Whereas ED may act primarily on only one specific endocrine target, all endocrine systems will eventually be deregulated as they are intimately connected to each other. The recent ecotoxicological issue of pharmaceutically active compounds (PhACs) present in the aquatic environment indicates a high potential for further endocrine modes of action on aquatic vertebrates by ED derived from PhACs, such as glucocorticoids, progestins, and beta-agonists.

  4. Vertebral osteomyelitis: assessment using MR.

    PubMed

    Modic, M T; Feiglin, D H; Piraino, D W; Boumphrey, F; Weinstein, M A; Duchesneau, P M; Rehm, S

    1985-10-01

    Thirty-seven patients who were clinically suspected of having vertebral osteomyelitis were prospectively evaluated with magnetic resonance (MR), radiography, and radionuclide studies. These findings were correlated with the final clinical, microbiologic, or histologic diagnoses. Based on the results of these latter studies, 23 patients were believed to have osteomyelitis. MR examinations consisted of at least a sagittal image (TE = 30 msec, TR = 0.5 sec) and an image obtained at TE = 120 msec, TR = 2-3 sec. All patients underwent radiographic and MR examinations, 36 underwent technetium 99m-HDP bone scanning, and 20 patients underwent gallium 67 scanning. Nineteen patients underwent both bone and gallium scanning. The imaging studies were reviewed independently by investigators blinded to the final diagnoses. MR had a sensitivity of 96%, specificity of 92%, and accuracy of 94%. Combined gallium and bone scan studies (19 cases) had a sensitivity of 90%, specificity of 100%, and accuracy of 94%. Bone scans alone had a sensitivity of 90%, specificity of 78%, and accuracy of 86%. Plain radiographs had a sensitivity of 82%, specificity of 57%, and accuracy of 73%. The MR appearance of vertebral osteomyelitis in this study was characteristic, and MR was as accurate and sensitive as radionuclide scanning in the detection of osteomyelitis.

  5. Ghrelin Receptors in Non-Mammalian Vertebrates

    PubMed Central

    Kaiya, Hiroyuki; Kangawa, Kenji; Miyazato, Mikiya

    2012-01-01

    The growth hormone secretagogue-receptor (GHS-R) was discovered in humans and pigs in 1996. The endogenous ligand, ghrelin, was discovered 3 years later, in 1999, and our understanding of the physiological significance of the ghrelin system in vertebrates has grown steadily since then. Although the ghrelin system in non-mammalian vertebrates is a subject of great interest, protein sequence data for the receptor in non-mammalian vertebrates has been limited until recently, and related biological information has not been well organized. In this review, we summarize current information related to the ghrelin receptor in non-mammalian vertebrates. PMID:23882259

  6. Numerical simulations of the blood flow through vertebral arteries.

    PubMed

    Jozwik, Krzysztof; Obidowski, Damian

    2010-01-19

    Vertebral arteries are two arteries whose structure and location in human body result in development of special flow conditions. For some of the arteries, one can observe a significant difference between flow rates in the left and the right arteries during ultrasonography diagnosis. Usually the reason of such a difference was connected with pathology of the artery in which a smaller flow rate was detected. Simulations of the flow through the selected type of the vertebral artery geometry for twenty five cases of artery diameters have been carried out. The main aim of the presented experiment was to visualize the flow in the region of vertebral arteries junction in the origin of the basilar artery. It is extremely difficult to examine this part of human circulation system, thus numerical experiments may be helpful in understanding the phenomena occurring when two relatively large arteries join together to form one vessel. The obtained results have shown that an individual configuration and diameters of particular arteries can exert an influence on the flow in them and affect a significant difference between flow rates for vertebral arteries. It has been assumed in the investigations that modelled arteries were absolutely normal, without any pathology. In the numerical experiment, the non-Newtonian model of blood was employed.

  7. Modeling vertebrate diversity in Oregon using satellite imagery

    NASA Astrophysics Data System (ADS)

    Cablk, Mary Elizabeth

    Vertebrate diversity was modeled for the state of Oregon using a parametric approach to regression tree analysis. This exploratory data analysis effectively modeled the non-linear relationships between vertebrate richness and phenology, terrain, and climate. Phenology was derived from time-series NOAA-AVHRR satellite imagery for the year 1992 using two methods: principal component analysis and derivation of EROS data center greenness metrics. These two measures of spatial and temporal vegetation condition incorporated the critical temporal element in this analysis. The first three principal components were shown to contain spatial and temporal information about the landscape and discriminated phenologically distinct regions in Oregon. Principal components 2 and 3, 6 greenness metrics, elevation, slope, aspect, annual precipitation, and annual seasonal temperature difference were investigated as correlates to amphibians, birds, all vertebrates, reptiles, and mammals. Variation explained for each regression tree by taxa were: amphibians (91%), birds (67%), all vertebrates (66%), reptiles (57%), and mammals (55%). Spatial statistics were used to quantify the pattern of each taxa and assess validity of resulting predictions from regression tree models. Regression tree analysis was relatively robust against spatial autocorrelation in the response data and graphical results indicated models were well fit to the data.

  8. A descending dopamine pathway conserved from basal vertebrates to mammals

    PubMed Central

    Ryczko, Dimitri; Cone, Jackson J.; Alpert, Michael H.; Goetz, Laurent; Auclair, François; Dubé, Catherine; Parent, Martin; Roitman, Mitchell F.; Alford, Simon; Dubuc, Réjean

    2016-01-01

    Dopamine neurons are classically known to modulate locomotion indirectly through ascending projections to the basal ganglia that project down to brainstem locomotor networks. Their loss in Parkinson’s disease is devastating. In lampreys, we recently showed that brainstem networks also receive direct descending dopaminergic inputs that potentiate locomotor output. Here, we provide evidence that this descending dopaminergic pathway is conserved to higher vertebrates, including mammals. In salamanders, dopamine neurons projecting to the striatum or brainstem locomotor networks were partly intermingled. Stimulation of the dopaminergic region evoked dopamine release in brainstem locomotor networks and concurrent reticulospinal activity. In rats, some dopamine neurons projecting to the striatum also innervated the pedunculopontine nucleus, a known locomotor center, and stimulation of the dopaminergic region evoked pedunculopontine dopamine release in vivo. Finally, we found dopaminergic fibers in the human pedunculopontine nucleus. The conservation of a descending dopaminergic pathway across vertebrates warrants re-evaluating dopamine’s role in locomotion. PMID:27071118

  9. Cystic Abnormalities of the Spinal Cord and Vertebral Column.

    PubMed

    da Costa, Ronaldo C; Cook, Laurie B

    2016-03-01

    Cystic lesions of the vertebral column and spinal cord are important differential diagnoses in dogs with signs of spinal cord disease. Synovial cysts are commonly associated with degenerative joint disease and usually affect the cervical and lumbosacral regions. Arachnoid diverticulum (previously known as cyst) is seen in the cervical region of large breed dogs and thoracolumbar region of small breed dogs. This article reviews the causes, diagnosis, and treatment of these and other, less common, cystic lesions. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Quantitative vertebral morphometry based on parametric modeling of vertebral bodies in 3D.

    PubMed

    Stern, D; Njagulj, V; Likar, B; Pernuš, F; Vrtovec, T

    2013-04-01

    Quantitative vertebral morphometry (QVM) was performed by parametric modeling of vertebral bodies in three dimensions (3D). Identification of vertebral fractures in two dimensions is a challenging task due to the projective nature of radiographic images and variability in the vertebral shape. By generating detailed 3D anatomical images, computed tomography (CT) enables accurate measurement of vertebral deformations and fractures. A detailed 3D representation of the vertebral body shape is obtained by automatically aligning a parametric 3D model to vertebral bodies in CT images. The parameters of the 3D model describe clinically meaningful morphometric vertebral body features, and QVM in 3D is performed by comparing the parameters to their statistical values. Thresholds and parameters that best discriminate between normal and fractured vertebral bodies are determined by applying statistical classification analysis. The proposed QVM in 3D was applied to 454 normal and 228 fractured vertebral bodies, yielding classification sensitivity of 92.5% at 7.5% specificity, with corresponding accuracy of 92.5% and precision of 86.1%. The 3D shape parameters that provided the best separation between normal and fractured vertebral bodies were the vertebral body height and the inclination and concavity of both vertebral endplates. The described QVM in 3D is able to efficiently and objectively discriminate between normal and fractured vertebral bodies and identify morphological cases (wedge, (bi)concavity, or crush) and grades (1, 2, or 3) of vertebral body fractures. It may be therefore valuable for diagnosing and predicting vertebral fractures in patients who are at risk of osteoporosis.

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

    PubMed

    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.

  12. Questioning hagfish affinities of the enigmatic Devonian vertebrate Palaeospondylus

    NASA Astrophysics Data System (ADS)

    Johanson, Zerina; Smith, Moya; Sanchez, Sophie; Senden, Tim; Trinajstic, Kate; Pfaff, Cathrin

    2017-07-01

    Palaeospondylus gunni Traquair, 1890 is an enigmatic Devonian vertebrate whose taxonomic affinities have been debated since it was first described. Most recently, Palaeospondylus has been identified as a stem-group hagfish (Myxinoidea). However, one character questioning this assignment is the presence of three semicircular canals in the otic region of the cartilaginous skull, a feature of jawed vertebrates. Additionally, new tomographic data reveal that the following characters of crown-group gnathostomes (chondrichthyans + osteichthyans) are present in Palaeospondylus: a longer telencephalic region of the braincase, separation of otic and occipital regions by the otico-occipital fissure, and vertebral centra. As well, a precerebral fontanelle and postorbital articulation of the palatoquadrate are characteristic of certain chondrichthyans. Similarities in the structure of the postorbital process to taxa such as Pucapampella, and possible presence of the ventral cranial fissure, both support a resolution of Pa. gunni as a stem chondrichthyan. The internally mineralized cartilaginous skeleton in Palaeospondylus may represent a stage in the loss of bone characteristic of the Chondrichthyes.

  13. Evolution and Functional Classification of Vertebrate Gene Deserts

    SciTech Connect

    Ovcharenko, I; Loots, G; Nobrega, M; Hardison, R; Miller, W; Stubbs, L

    2004-07-14

    Gene deserts, long stretches of DNA sequence devoid of protein coding genes, span approximately one quarter of the human genome. Through human-chicken genome comparisons we were able to characterized one third of human gene deserts as evolutionarily stable - they are highly conserved in vertebrates, resist chromosomal rearrangements, and contain multiple conserved non-coding elements physically linked to their neighboring genes. A linear relationship was observed between human and chicken orthologous stable gene deserts, where the human deserts appear to have expanded homogeneously by a uniform accumulation of repetitive elements. Stable gene deserts are associated with key vertebrate genes that construct the framework of vertebrate development; many of which encode transcription factors. We show that the regulatory machinery governing genes associated with stable gene deserts operates differently from other regions in the human genome and relies heavily on distant regulatory elements. The regulation guided by these elements is independent of the distance between the gene and its distant regulatory element, or the distance between two distant regulatory cassettes. The location of gene deserts and their associated genes in the genome is independent of chromosomal length or content presenting these regions as well-bounded regions evolving separately from the rest of the genome.

  14. Molecular evolution of shark and other vertebrate DNases I.

    PubMed

    Yasuda, Toshihiro; Iida, Reiko; Ueki, Misuzu; Kominato, Yoshihiko; Nakajima, Tamiko; Takeshita, Haruo; Kobayashi, Takanori; Kishi, Koichiro

    2004-11-01

    We purified pancreatic deoxyribonuclease I (DNase I) from the shark Heterodontus japonicus using three-step column chromatography. Although its enzymatic properties resembled those of other vertebrate DNases I, shark DNase I was unique in being a basic protein. Full-length cDNAs encoding the DNases I of two shark species, H. japonicus and Triakis scyllia, were constructed from their total pancreatic RNAs using RACE. Nucleotide sequence analyses revealed two structural alterations unique to shark enzymes: substitution of two Cys residues at positions 101 and 104 (which are well conserved in all other vertebrate DNases I) and insertion of an additional Thr or Asn residue into an essential Ca(2+)-binding site. Site-directed mutagenesis of shark DNase I indicated that both of these alterations reduced the stability of the enzyme. When the signal sequence region of human DNase I (which has a high alpha-helical structure content) was replaced with its amphibian, fish and shark counterparts (which have low alpha-helical structure contents), the activity expressed by the chimeric mutant constructs in transfected mammalian cells was approximately half that of the wild-type enzyme. In contrast, substitution of the human signal sequence region into the amphibian, fish and shark enzymes produced higher activity compared with the wild-types. The vertebrate DNase I family may have acquired high stability and effective expression of the enzyme protein through structural alterations in both the mature protein and its signal sequence regions during molecular evolution.

  15. Building the backbone: the development and evolution of vertebral patterning.

    PubMed

    Fleming, Angeleen; Kishida, Marcia G; Kimmel, Charles B; Keynes, Roger J

    2015-05-15

    The segmented vertebral column comprises a repeat series of vertebrae, each consisting of two key components: the vertebral body (or centrum) and the vertebral arches. Despite being a defining feature of the vertebrates, much remains to be understood about vertebral development and evolution. Particular controversy surrounds whether vertebral component structures are homologous across vertebrates, how somite and vertebral patterning are connected, and the developmental origin of vertebral bone-mineralizing cells. Here, we assemble evidence from ichthyologists, palaeontologists and developmental biologists to consider these issues. Vertebral arch elements were present in early stem vertebrates, whereas centra arose later. We argue that centra are homologous among jawed vertebrates, and review evidence in teleosts that the notochord plays an instructive role in segmental patterning, alongside the somites, and contributes to mineralization. By clarifying the evolutionary relationship between centra and arches, and their varying modes of skeletal mineralization, we can better appreciate the detailed mechanisms that regulate and diversify vertebral patterning.

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

    PubMed

    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.

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

    PubMed

    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

  18. Vertebral architecture in the earliest stem tetrapods.

    PubMed

    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.

  19. The evolution of adaptive immunity in vertebrates.

    PubMed

    Hirano, Masayuki; Das, Sabyasachi; Guo, Peng; Cooper, Max D

    2011-01-01

    Approximately 500 million years ago, two types of recombinatorial adaptive immune systems (AISs) arose in vertebrates. The jawed vertebrates diversify their repertoire of immunoglobulin domain-based T and B cell antigen receptors mainly through the rearrangement of V(D)J gene segments and somatic hypermutation, but none of the fundamental AIS recognition elements in jawed vertebrates have been found in jawless vertebrates. Instead, the AIS of jawless vertebrates is based on variable lymphocyte receptors (VLRs) that are generated through recombinatorial usage of a large panel of highly diverse leucine-rich-repeat (LRR) sequences. Whereas the appearance of transposon-like, recombination-activating genes contributed uniquely to the origin of the AIS in jawed vertebrates, the use of activation-induced cytidine deaminase for receptor diversification is common to both the jawed and jawless vertebrates. Despite these differences in anticipatory receptor construction, the basic AIS design featuring two interactive T and B lymphocyte arms apparently evolved in an ancestor of jawed and jawless vertebrates within the context of preexisting innate immunity and has been maintained since as a consequence of powerful and enduring selection, most probably for pathogen defense purposes.

  20. Eye marks in vertebrates: AIDS to vision.

    PubMed

    Ficken, R W; Matthiae, P E; Horwich, R

    1971-09-03

    Lines leading forward from the eye may function as aiming sights in many small vertebrates. The chief evidence is the correlation of distribution and positions of eye-lines in various vertebrate groups with predatory feeding habits. Dark patches around the eye may serve to reduce glare in species in bright environments. Facial patterns often have multiple functions.

  1. Vertebral osteomyelitis in insulin-dependent diabetics.

    PubMed

    Cooppan, R; Schoenbaum, S; Younger, M D; Freidberg, S; D'elia, J

    1976-11-20

    Vertebral osteomyelitis continues to be a diagnostically and therapeutically challenging disease with a relatively high incidence in diabetics. The clinical features, investigations and treatment of 7 insulin-dependent diabetics with vertebral osteomyelitis are presented and possible aetiological factors in this group are discussed.

  2. Duplication and maintenance of the Myb genes of vertebrate animals.

    PubMed

    Davidson, Colin J; Guthrie, Erin E; Lipsick, Joseph S

    2013-02-15

    Gene duplication is an important means of generating new genes. The major mechanisms by which duplicated genes are preserved in the face of purifying selection are thought to be neofunctionalization, subfunctionalization, and increased gene dosage. However, very few duplicated gene families in vertebrate species have been analyzed by functional tests in vivo. We have therefore examined the three vertebrate Myb genes (c-Myb, A-Myb, and B-Myb) by cytogenetic map analysis, by sequence analysis, and by ectopic expression in Drosophila. We provide evidence that the vertebrate Myb genes arose by two rounds of regional genomic duplication. We found that ubiquitous expression of c-Myb and A-Myb, but not of B-Myb or Drosophila Myb, was lethal in Drosophila. Expression of any of these genes during early larval eye development was well tolerated. However, expression of c-Myb and A-Myb, but not of B-Myb or Drosophila Myb, during late larval eye development caused drastic alterations in adult eye morphology. Mosaic analysis implied that this eye phenotype was cell-autonomous. Interestingly, some of the eye phenotypes caused by the retroviral v-Myb oncogene and the normal c-Myb proto-oncogene from which v-Myb arose were quite distinct. Finally, we found that post-translational modifications of c-Myb by the GSK-3 protein kinase and by the Ubc9 SUMO-conjugating enzyme that normally occur in vertebrate cells can modify the eye phenotype caused by c-Myb in Drosophila. These results support a model in which the three Myb genes of vertebrates arose by two sequential duplications. The first duplication was followed by a subfunctionalization of gene expression, then neofunctionalization of protein function to yield a c/A-Myb progenitor. The duplication of this progenitor was followed by subfunctionalization of gene expression to give rise to tissue-specific c-Myb and A-Myb genes.

  3. Comparison of Ultra-Conserved Elements in Drosophilids and Vertebrates

    PubMed Central

    Makunin, Igor V.; Shloma, Viktor V.; Stephen, Stuart J.; Pheasant, Michael; Belyakin, Stepan N.

    2013-01-01

    Metazoan genomes contain many ultra-conserved elements (UCEs), long sequences identical between distant species. In this study we identified UCEs in drosophilid and vertebrate species with a similar level of phylogenetic divergence measured at protein-coding regions, and demonstrated that both the length and number of UCEs are larger in vertebrates. The proportion of non-exonic UCEs declines in distant drosophilids whilst an opposite trend was observed in vertebrates. We generated a set of 2,126 Sophophora UCEs by merging elements identified in several drosophila species and compared these to the eutherian UCEs identified in placental mammals. In contrast to vertebrates, the Sophophora UCEs are depleted around transcription start sites. Analysis of 52,954 P-element, piggyBac and Minos insertions in the D. melanogaster genome revealed depletion of the P-element and piggyBac insertions in and around the Sophophora UCEs. We examined eleven fly strains with transposon insertions into the intergenic UCEs and identified associated phenotypes in five strains. Four insertions behave as recessive lethals, and in one case we observed a suppression of the marker gene within the transgene, presumably by silenced chromatin around the integration site. To confirm the lethality is caused by integration of transposons we performed a phenotype rescue experiment for two stocks and demonstrated that the excision of the transposons from the intergenic UCEs restores viability. Sequencing of DNA after the transposon excision in one fly strain with the restored viability revealed a 47 bp insertion at the original transposon integration site suggesting that the nature of the mutation is important for the appearance of the phenotype. Our results suggest that the UCEs in flies and vertebrates have both common and distinct features, and demonstrate that a significant proportion of intergenic drosophila UCEs are sensitive to disruption. PMID:24349264

  4. Comparison of ultra-conserved elements in drosophilids and vertebrates.

    PubMed

    Makunin, Igor V; Shloma, Viktor V; Stephen, Stuart J; Pheasant, Michael; Belyakin, Stepan N

    2013-01-01

    Metazoan genomes contain many ultra-conserved elements (UCEs), long sequences identical between distant species. In this study we identified UCEs in drosophilid and vertebrate species with a similar level of phylogenetic divergence measured at protein-coding regions, and demonstrated that both the length and number of UCEs are larger in vertebrates. The proportion of non-exonic UCEs declines in distant drosophilids whilst an opposite trend was observed in vertebrates. We generated a set of 2,126 Sophophora UCEs by merging elements identified in several drosophila species and compared these to the eutherian UCEs identified in placental mammals. In contrast to vertebrates, the Sophophora UCEs are depleted around transcription start sites. Analysis of 52,954 P-element, piggyBac and Minos insertions in the D. melanogaster genome revealed depletion of the P-element and piggyBac insertions in and around the Sophophora UCEs. We examined eleven fly strains with transposon insertions into the intergenic UCEs and identified associated phenotypes in five strains. Four insertions behave as recessive lethals, and in one case we observed a suppression of the marker gene within the transgene, presumably by silenced chromatin around the integration site. To confirm the lethality is caused by integration of transposons we performed a phenotype rescue experiment for two stocks and demonstrated that the excision of the transposons from the intergenic UCEs restores viability. Sequencing of DNA after the transposon excision in one fly strain with the restored viability revealed a 47 bp insertion at the original transposon integration site suggesting that the nature of the mutation is important for the appearance of the phenotype. Our results suggest that the UCEs in flies and vertebrates have both common and distinct features, and demonstrate that a significant proportion of intergenic drosophila UCEs are sensitive to disruption.

  5. Morphometric Relationship between the Cervicothoracic Cord Segments and Vertebral Bodies

    PubMed Central

    Kim, Ji Hoon; Lee, Chul Woo; Chun, Kwon Soo; Shin, Won Han; Bae, Hack-Gun

    2012-01-01

    Objective The objective of this study was to investigate the morphologic characteristics between the vertebral body and the regions of the cervical and thoracic spinal cords where each rootlets branch out. Methods Sixteen adult cadavers (12 males and 4 females) with a mean age of 57.9 (range of 33 to 70 years old) were used in this study. The anatomical relationship between the exit points of the nerve roots from the posterior root entry zone at each spinal cord segment and their corresponding relevant vertebral bodies were also analyzed. Results Vertical span of the posterior root entry zone between the upper and lower rootlet originating from each spinal segment ranged from 10-12 mm. The lengths of the rootlets from their point of origin at the spinal cord to their entrance into the intervertebral foramen were 5.9 mm at the third cervical nerve root and increased to 14.5 mm at the eighth cervical nerve root. At the lower segments of the nerve roots (T3 to T12), the posterior root entry zone of the relevant nerve roots had a corresponding anatomical relationship with the vertebral body that is two segments above. The posterior root entry zones of the sixth (94%) and seventh (81%) cervical nerve roots were located at a vertebral body a segment above from relevant segment. Conclusion Through these investigations, a more accurate diagnosis, the establishment of a better therapeutic plan, and a decrease in surgical complications can be expected when pathologic lesions occur in the spinal cord or vertebral body. PMID:23133729

  6. Lamprey: a model for vertebrate evolutionary research.

    PubMed

    Xu, Yang; Zhu, Si-Wei; Li, Qing-Wei

    2016-09-18

    Lampreys belong to the superclass Cyclostomata and represent the most ancient group of vertebrates. Existing for over 360 million years, they are known as living fossils due to their many evolutionally conserved features. They are not only a keystone species for studying the origin and evolution of vertebrates, but also one of the best models for researching vertebrate embryonic development and organ differentiation. From the perspective of genetic information, the lamprey genome remains primitive compared with that of other higher vertebrates, and possesses abundant functional genes. Through scientific and technological progress, scientists have conducted in-depth studies on the nervous, endocrine, and immune systems of lampreys. Such research has significance for understanding and revealing the origin and evolution of vertebrates, and could contribute to a greater understanding of human diseases and treatments. This review presents the current progress and significance of lamprey research.

  7. Lamprey: a model for vertebrate evolutionary research

    PubMed Central

    XU, Yang; ZHU, Si-Wei; LI, Qing-Wei

    2016-01-01

    Lampreys belong to the superclass Cyclostomata and represent the most ancient group of vertebrates. Existing for over 360 million years, they are known as living fossils due to their many evolutionally conserved features. They are not only a keystone species for studying the origin and evolution of vertebrates, but also one of the best models for researching vertebrate embryonic development and organ differentiation. From the perspective of genetic information, the lamprey genome remains primitive compared with that of other higher vertebrates, and possesses abundant functional genes. Through scientific and technological progress, scientists have conducted in-depth studies on the nervous, endocrine, and immune systems of lampreys. Such research has significance for understanding and revealing the origin and evolution of vertebrates, and could contribute to a greater understanding of human diseases and treatments. This review presents the current progress and significance of lamprey research. PMID:27686784

  8. Nanotechnology for treating osteoporotic vertebral fractures

    PubMed Central

    Gao, Chunxia; Wei, Donglei; Yang, Huilin; Chen, Tao; Yang, Lei

    2015-01-01

    Osteoporosis is a serious public health problem affecting hundreds of millions of aged people worldwide, with severe consequences including vertebral fractures that are associated with significant morbidity and mortality. To augment or treat osteoporotic vertebral fractures, a number of surgical approaches including minimally invasive vertebroplasty and kyphoplasty have been developed. However, these approaches face problems and difficulties with efficacy and long-term stability. Recent advances and progress in nanotechnology are opening up new opportunities to improve the surgical procedures for treating osteoporotic vertebral fractures. This article reviews the improvements enabled by new nanomaterials and focuses on new injectable biomaterials like bone cements and surgical instruments for treating vertebral fractures. This article also provides an introduction to osteoporotic vertebral fractures and current clinical treatments, along with the rationale and efficacy of utilizing nanomaterials to modify and improve biomaterials or instruments. In addition, perspectives on future trends with injectable bone cements and surgical instruments enhanced by nanotechnology are provided. PMID:26316746

  9. Nanotechnology for treating osteoporotic vertebral fractures.

    PubMed

    Gao, Chunxia; Wei, Donglei; Yang, Huilin; Chen, Tao; Yang, Lei

    2015-01-01

    Osteoporosis is a serious public health problem affecting hundreds of millions of aged people worldwide, with severe consequences including vertebral fractures that are associated with significant morbidity and mortality. To augment or treat osteoporotic vertebral fractures, a number of surgical approaches including minimally invasive vertebroplasty and kyphoplasty have been developed. However, these approaches face problems and difficulties with efficacy and long-term stability. Recent advances and progress in nanotechnology are opening up new opportunities to improve the surgical procedures for treating osteoporotic vertebral fractures. This article reviews the improvements enabled by new nanomaterials and focuses on new injectable biomaterials like bone cements and surgical instruments for treating vertebral fractures. This article also provides an introduction to osteoporotic vertebral fractures and current clinical treatments, along with the rationale and efficacy of utilizing nanomaterials to modify and improve biomaterials or instruments. In addition, perspectives on future trends with injectable bone cements and surgical instruments enhanced by nanotechnology are provided.

  10. Evolutionary Diversification of the Vertebrate Transferrin Multi-gene Family

    PubMed Central

    Hughes, Austin L.; Friedman, Robert

    2014-01-01

    In a phylogenetic analysis of vertebrate transferrins (TFs), six major clades (subfamilies) were identified: (1) S, the mammalian serotransferrins; (2) ICA, the mammalian inhibitor of carbonic anhydrase (ICA) homologs; (3) L, the mammalian lactoferrins; (4) O, the ovotransferrins of birds and reptiles; (4) M, the melanotransferrins of bony fishes, amphibians, reptiles, birds, and mammals; and (5) M-like, a newly identified TF subfamily found in bony fishes, amphibians, reptiles, and birds. A phylogenetic tree based on the joint alignment of N-lobes and C-lobes supported the hypothesis that three separate events of internal duplication occurred in vertebrate TFs: (1) in the common ancestor of the M subfamily; (2) in the common ancestor of the M-like subfamily; and (3) in the common ancestor of other vertebrate TFs. The S, ICA, and L subfamilies were found only in placental mammals, and the phylogenetic analysis supported the hypothesis that these three subfamilies arose by gene duplication after the divergence of placental mammals from marsupials. The M-like subfamily was unusual in several respects, including the presence of a uniquely high proportion of clade-specific conserved residues, including distinctive but conserved residues in the sites homologous to those functioning in carbonate binding of human serotransferrin. The M-like family also showed a unusually high proportion of cationic residues in the positively charged region corresponding to human lactoferrampin, suggesting a distinctive role of this region in the M-like subfamily, perhaps in antimicrobial defense. PMID:25142446

  11. Evolution of oxytocin pathways in the brain of vertebrates

    PubMed Central

    Knobloch, H. Sophie; Grinevich, Valery

    2014-01-01

    The central oxytocin system transformed tremendously during the evolution, thereby adapting to the expanding properties of species. In more basal vertebrates (paraphyletic taxon Anamnia, which includes agnathans, fish and amphibians), magnocellular neurosecretory neurons producing homologs of oxytocin reside in the wall of the third ventricle of the hypothalamus composing a single hypothalamic structure, the preoptic nucleus. This nucleus further diverged in advanced vertebrates (monophyletic taxon Amniota, which includes reptiles, birds, and mammals) into the paraventricular and supraoptic nuclei with accessory nuclei (AN) between them. The individual magnocellular neurons underwent a process of transformation from primitive uni- or bipolar neurons into highly differentiated neurons. Due to these microanatomical and cytological changes, the ancient release modes of oxytocin into the cerebrospinal fluid were largely replaced by vascular release. However, the most fascinating feature of the progressive transformations of the oxytocin system has been the expansion of oxytocin axonal projections to forebrain regions. In the present review we provide a background on these evolutionary advancements. Furthermore, we draw attention to the non-synaptic axonal release in small and defined brain regions with the aim to clearly distinguish this way of oxytocin action from the classical synaptic transmission on one side and from dendritic release followed by a global diffusion on the other side. Finally, we will summarize the effects of oxytocin and its homologs on pro-social reproductive behaviors in representatives of the phylogenetic tree and will propose anatomically plausible pathways of oxytocin release contributing to these behaviors in basal vertebrates and amniots. PMID:24592219

  12. Evolutionary diversification of the vertebrate transferrin multi-gene family.

    PubMed

    Hughes, Austin L; Friedman, Robert

    2014-11-01

    In a phylogenetic analysis of vertebrate transferrins (TFs), six major clades (subfamilies) were identified: (a) S, the mammalian serotransferrins; (b) ICA, the mammalian inhibitor of carbonic anhydrase (ICA) homologs; (c) L, the mammalian lactoferrins; (d) O, the ovotransferrins of birds and reptiles; (e) M, the melanotransferrins of bony fishes, amphibians, reptiles, birds, and mammals; and (f) M-like, a newly identified TF subfamily found in bony fishes, amphibians, reptiles, and birds. A phylogenetic tree based on the joint alignment of N-lobes and C-lobes supported the hypothesis that three separate events of internal duplication occurred in vertebrate TFs: (a) in the common ancestor of the M subfamily, (b) in the common ancestor of the M-like subfamily, and (c) in the common ancestor of other vertebrate TFs. The S, ICA, and L subfamilies were found only in placental mammals, and the phylogenetic analysis supported the hypothesis that these three subfamilies arose by gene duplication after the divergence of placental mammals from marsupials. The M-like subfamily was unusual in several respects, including the presence of a uniquely high proportion of clade-specific conserved residues, including distinctive but conserved residues in the sites homologous to those functioning in carbonate binding of human serotransferrin. The M-like family also showed an unusually high proportion of cationic residues in the positively charged region corresponding to human lactoferrampin, suggesting a distinctive role of this region in the M-like subfamily, perhaps in antimicrobial defense.

  13. The prevalence of vertebral fracture amongst patients presenting with non-vertebral fractures.

    PubMed

    Gallacher, S J; Gallagher, A P; McQuillian, C; Mitchell, P J; Dixon, T

    2007-02-01

    Despite vertebral fracture being a significant risk factor for further fracture, vertebral fractures are often unrecognised. A study was therefore conducted to determine the proportion of patients presenting with a non-vertebral fracture who also have an unrecognised vertebral fracture. Prospective study of patients presenting with a non-vertebral fracture in South Glasgow who underwent DXA evaluation with vertebral morphometry (MXA) from DV5/6 to LV4/5. Vertebral deformities (consistent with fracture) were identified by direct visualisation using the Genant semi-quantitative grading scale. Data were available for 337 patients presenting with low trauma non-vertebral fracture; 261 were female. Of all patients, 10.4% were aged 50-64 years, 53.2% were aged 65-74 years and 36.2% were aged 75 years or over. According to WHO definitions, 35.0% of patients had normal lumbar spine BMD (T-score -1 or above), 37.4% were osteopenic (T-score -1.1 to -2.4) and 27.6% osteoporotic (T-score -2.5 or lower). Humerus (n=103, 31%), radius-ulna (n=90, 27%) and hand/foot (n=53, 16%) were the most common fractures. For 72% of patients (n=241) the presenting fracture was the first low trauma fracture to come to clinical attention. The overall prevalence of vertebral deformity established by MXA was 25% (n=83); 45% (n=37) of patients with vertebral deformity had deformities of more than one vertebra. Of the patients with vertebral deformity and readable scans for grading, 72.5% (58/80) had deformities of grade 2 or 3. Patients presenting with hip fracture, or spine T-score vertebral fracture were all significantly more likely to have evidence of a prevalent vertebral deformity (p<0.05). However, 19.8% of patients with an osteopenic T-score had a vertebral deformity (48% of which were multiple), and 16.1% of patients with a normal T-score had a vertebral deformity (26.3% of which were multiple). Following non-vertebral fracture, some

  14. Hox genes control vertebrate body elongation by collinear Wnt repression.

    PubMed

    Denans, Nicolas; Iimura, Tadahiro; Pourquié, Olivier

    2015-02-26

    In vertebrates, the total number of vertebrae is precisely defined. Vertebrae derive from embryonic somites that are continuously produced posteriorly from the presomitic mesoderm (PSM) during body formation. We show that in the chicken embryo, activation of posterior Hox genes (paralogs 9-13) in the tail-bud correlates with the slowing down of axis elongation. Our data indicate that a subset of progressively more posterior Hox genes, which are collinearly activated in vertebral precursors, repress Wnt activity with increasing strength. This leads to a graded repression of the Brachyury/T transcription factor, reducing mesoderm ingression and slowing down the elongation process. Due to the continuation of somite formation, this mechanism leads to the progressive reduction of PSM size. This ultimately brings the retinoic acid (RA)-producing segmented region in close vicinity to the tail bud, potentially accounting for the termination of segmentation and axis elongation.

  15. The Vertebrate Genome Annotation browser 10 years on.

    PubMed

    Harrow, Jennifer L; Steward, Charles A; Frankish, Adam; Gilbert, James G; Gonzalez, Jose M; Loveland, Jane E; Mudge, Jonathan; Sheppard, Dan; Thomas, Mark; Trevanion, Stephen; Wilming, Laurens G

    2014-01-01

    The Vertebrate Genome Annotation (VEGA) database (http://vega.sanger.ac.uk), initially designed as a community resource for browsing manual annotation of the human genome project, now contains five reference genomes (human, mouse, zebrafish, pig and rat). Its introduction pages have been redesigned to enable the user to easily navigate between whole genomes and smaller multi-species haplotypic regions of interest such as the major histocompatibility complex. The VEGA browser is unique in that annotation is updated via the Human And Vertebrate Analysis aNd Annotation (HAVANA) update track every 2 weeks, allowing single gene updates to be made publicly available to the research community quickly. The user can now access different haplotypic subregions more easily, such as those from the non-obese diabetic mouse, and display them in a more intuitive way using the comparative tools. We also highlight how the user can browse manually annotated updated patches from the Genome Reference Consortium (GRC).

  16. Compartmentalization of vertebrate optic neuroephithelium: external cues and transcription factors.

    PubMed

    Kim, Hyoung-Tai; Kim, Jin Woo

    2012-04-01

    The vertebrate eye is a laterally extended structure of the forebrain. It develops through a series of events, including specification and regionalization of the anterior neural plate, evagination of the optic vesicle (OV), and development of three distinct optic structures: the neural retina (NR), optic stalk (OS), and retinal pigment epithelium (RPE). Various external signals that act on the optic neuroepithelium in a spatial- and temporal-specific manner control the fates of OV subdomains by inducing localized expression of key transcription factors. Investigating the mechanisms underlying compartmentalization of these distinct optic neuroepithelium-derived tissues is therefore not only important from the standpoint of accounting for vertebrate eye morphogenesis, it is also helpful for understanding the fundamental basis of fate determination of other neuroectoderm- derived tissues. This review focuses on the molecular signatures of OV subdomains and the external factors that direct the development of tissues originating from the OV.

  17. Anterior endoderm and head induction in early vertebrate embryos.

    PubMed

    de Souza, F S; Niehrs, C

    2000-05-01

    Early work on the formation of the vertebrate body axis indicated the existence of separate head- and trunk-inducing regions in Spemann's organizer of the amphibian gastrula. In mammals some head-organizing activity may be located in anterior visceral (extraembryonic) endoderm (AVE). By analogy, the equivalent structure in the Xenopus laevis gastrula, the anterior endoderm, has been proposed to be the amphibian head organizer. Here we review recent data that challenge this notion and indicate that the involvement of AVE in head induction seems to be an exclusively mammalian characteristic. In X. laevis and chick, it is the prechordal endomesoderm that is the dominant source of head-inducing signals during early gastrulation. Furthermore, head induction in mammals needs a combination of signals from anterior primitive endoderm, prechordal plate, and anterior ectoderm. Thus, despite the homology of vertebrate anterior primitive endoderm, a role in head induction seems not to be conserved.

  18. Contribution of the vertebral artery to cerebral circulation in the rat snake Elaphe obsoleta

    NASA Technical Reports Server (NTRS)

    Zippel, K. C.; Lillywhite, H. B.; Mladinich, C. R.; Hargens, A. (Principal Investigator)

    1998-01-01

    Blood supplying the brain in vertebrates is carried primarily by the carotid vasculature. In most mammals, cerebral blood flow is supplemented by the vertebral arteries, which anastomose with the carotids at the base of the brain. In other tetrapods, cerebral blood is generally believed to be supplied exclusively by the carotid vasculature, and the vertebral arteries are usually described as disappearing into the dorsal musculature between the heart and head. There have been several reports of a vertebral artery connection with the cephalic vasculature in snakes. We measured regional blood flows using fluorescently labeled microspheres and demonstrated that the vertebral artery contributes a small but significant fraction of cerebral blood flow (approximately 13% of total) in the rat snake Elaphe obsoleta. Vascular casts of the anterior vessels revealed that the vertebral artery connection is indirect, through multiple anastomoses with the inferior spinal artery, which connects with the carotid vasculature near the base of the skull. Using digital subtraction angiography, fluoroscopy, and direct observations of flow in isolated vessels, we confirmed that blood in the inferior spinal artery flows craniad from a point anterior to the vertebral artery connections. Such collateral blood supply could potentially contribute to the maintenance of cerebral circulation during circumstances when craniad blood flow is compromised, e.g., during the gravitational stress of climbing.

  19. Contribution of the vertebral artery to cerebral circulation in the rat snake Elaphe obsoleta

    NASA Technical Reports Server (NTRS)

    Zippel, K. C.; Lillywhite, H. B.; Mladinich, C. R.; Hargens, A. (Principal Investigator)

    1998-01-01

    Blood supplying the brain in vertebrates is carried primarily by the carotid vasculature. In most mammals, cerebral blood flow is supplemented by the vertebral arteries, which anastomose with the carotids at the base of the brain. In other tetrapods, cerebral blood is generally believed to be supplied exclusively by the carotid vasculature, and the vertebral arteries are usually described as disappearing into the dorsal musculature between the heart and head. There have been several reports of a vertebral artery connection with the cephalic vasculature in snakes. We measured regional blood flows using fluorescently labeled microspheres and demonstrated that the vertebral artery contributes a small but significant fraction of cerebral blood flow (approximately 13% of total) in the rat snake Elaphe obsoleta. Vascular casts of the anterior vessels revealed that the vertebral artery connection is indirect, through multiple anastomoses with the inferior spinal artery, which connects with the carotid vasculature near the base of the skull. Using digital subtraction angiography, fluoroscopy, and direct observations of flow in isolated vessels, we confirmed that blood in the inferior spinal artery flows craniad from a point anterior to the vertebral artery connections. Such collateral blood supply could potentially contribute to the maintenance of cerebral circulation during circumstances when craniad blood flow is compromised, e.g., during the gravitational stress of climbing.

  20. Phylostratigraphic Profiles in Zebrafish Uncover Chordate Origins of the Vertebrate Brain

    PubMed Central

    Šestak, Martin Sebastijan; Domazet-Lošo, Tomislav

    2015-01-01

    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. PMID:25415965

  1. Ethnic difference of clinical vertebral fracture risk.

    PubMed

    Bow, C H; Cheung, E; Cheung, C L; Xiao, S M; Loong, C; Soong, C; Tan, K C; Luckey, M M; Cauley, J A; Fujiwara, S; Kung, A W C

    2012-03-01

    Vertebral fractures are the most common osteoporotic fractures. Data on the vertebral fracture risk in Asia remain sparse. This study observed that Hong Kong Chinese and Japanese populations have a less dramatic increase in hip fracture rates associated with age than Caucasians, but the vertebral fracture rates were higher, resulting in a high vertebral-to-hip fracture ratio. As a result, estimation of the absolute fracture risk for Asians may need to be readjusted for the higher clinical vertebral fracture rate. Vertebral fractures are the most common osteoporotic fractures. Data on the vertebral fracture risk in Asia remain sparse. The aim of this study was to report the incidence of clinical vertebral fractures among the Chinese and to compare the vertebral-to-hip fracture risk to other ethnic groups. Four thousand, three hundred eighty-six community-dwelling Southern Chinese subjects (2,302 women and 1,810 men) aged 50 or above were recruited in the Hong Kong Osteoporosis Study since 1995. Baseline demographic characteristics and medical history were obtained. Subjects were followed annually for fracture outcomes with a structured questionnaire and verified by the computerized patient information system of the Hospital Authority of the Hong Kong Government. Only non-traumatic incident hip fractures and clinical vertebral fractures that received medical attention were included in the analysis. The incidence rates of clinical vertebral fractures and hip fractures were determined and compared to the published data of Swedish Caucasian and Japanese populations. The mean age at baseline was 62 ± 8.2 years for women and 68 ± 10.3 years for men. The average duration of follow-up was 4.0 ± 2.8 (range, 1 to 14) years for a total of 14,733 person-years for the whole cohort. The incidence rate for vertebral fracture was 194/100,000 person-years in men and 508/100,000 person-years in women, respectively. For subjects above the age of 65, the clinical

  2. [Spasmodic torticollis and vertebral hemangioma].

    PubMed

    Durán, E; Chacón, J R

    Spasmodic torticollis in young patients should give rise to a clinical suspicion that this is secondary to another primary disorder. Therefore a series of diagnostic tests should be carried out before it is labelled as idiopathic. The patient was a thirty year old man who had had difficulty in writing with his right hand since childhood. At the age of 20 years he was diagnosed as having writer's cramp and idiopathic spasmodic torticollis. On general physical examination no abnormalities were found. On neurological examination he had: absence of reflexes of both arms, limited but painless rotation of the neck towards the left and hypertrophy of the left trapezius muscle. Laboratory, neurophysiological and neuroimaging investigations seeking a secondary cause for the torticollis were all normal. There were no Keyser-Fleischer rings. Chest X-ray showed, dorsal scoliosis with convexity to the left. CAT and MR of the spine showed a hemangioma in the body of T1. On arteriography of the supra-aortic and vertebral trunks a hemangioma was found at T1 which received contrast material via a branch of the right thyro-bi-cervico-scapular trunk. Various treatments were tried (diazepam, Botox, Dysport, tetrabenazine, baclofen, etc.) with no improvement. A definite diagnosis of secondary torticollis could not be made since the hemangioma was supplied by a very narrow vascular pedicle, so embolization was contraindicated. Cervical spinal cord alterations may cause focal dystonia due to increased excitability of the spinal motor neurone, due to dysfunction of the disinhibitory descending reciprocal paths.

  3. Rotations in a Vertebrate Setting

    NASA Astrophysics Data System (ADS)

    McCollum, Gin

    2003-05-01

    Rotational movements of the head are often considered to be measured in a single three dimensional coordinate system implemented by the semicircular canals of the vestibular system of the inner ear. However, the vertebrate body -- including the nervous system -- obeys rectangular symmetries alien to rotation groups. At best, nervous systems mimic the physical rotation group in a fragmented way, only partially reintegrating physical movements in whole organism responses. The vestibular canal reference frame is widely used in nervous systems, for example by eye movements. It is used to some extent even in the cerebrum, as evidenced by the remission of hemineglect -- in which half of space is ignored -- when the vestibular system is stimulated. However, reintegration of space by the organism remains incomplete. For example, compensatory eye movements (which in most cases aid visual fixation) may disagree with conscious self-motion perception. In addition, movement-induced nausea, illusions, and cue-free perceptions demonstrate symmetry breaking or incomplete spatial symmetries. As part of a long-term project to investigate rotation groups in nervous systems, we have analyzed the symmetry group of a primary vestibulo-spinal projection.

  4. Heterogeneity of vertebrate brain tubulins.

    PubMed Central

    Field, D J; Collins, R A; Lee, J C

    1984-01-01

    We have examined the extent of brain tubulin heterogeneity in six vertebrate species commonly used in tubulin research (rat, calf, pig, chicken, human, and lamb) using isoelectric focusing, two-dimensional electrophoresis, and peptide mapping procedures that provide higher resolution than previously available. The extent of heterogeneity is extremely similar in all of these organisms, as judged by number, range of isoelectric points, and distribution of the isotubulins. A minimum of 6 alpha and 12 beta tubulins was resolved from all sources. Even the pattern of spots on two-dimensional peptide maps is remarkably similar. These similarities suggest that the populations of tubulin in all of these brains should have similar overall physical properties. It is particularly interesting that chicken, which has only four or five beta-tubulin genes, contains approximately 12 beta tubulins. Thus, post-translational modification must generate at least some of the tubulin heterogeneity. Mammalian species, which contain 15-20 tubulin DNA sequences, do not show any more tubulin protein heterogeneity than does chicken. This suggests that expression of only a small number of the mammalian genes may be required to generate the observed tubulin heterogeneity. Images PMID:6588378

  5. Semaphorin Signaling in Vertebrate Neural Circuit Assembly

    PubMed Central

    Yoshida, Yutaka

    2012-01-01

    Neural circuit formation requires the coordination of many complex developmental processes. First, neurons project axons over long distances to find their final targets and then establish appropriate connectivity essential for the formation of neuronal circuitry. Growth cones, the leading edges of axons, navigate by interacting with a variety of attractive and repulsive axon guidance cues along their trajectories and at final target regions. In addition to guidance of axons, neuronal polarization, neuronal migration, and dendrite development must be precisely regulated during development to establish proper neural circuitry. Semaphorins consist of a large protein family, which includes secreted and cell surface proteins, and they play important roles in many steps of neural circuit formation. The major semaphorin receptors are plexins and neuropilins, however other receptors and co-receptors also mediate signaling by semaphorins. Upon semaphorin binding to their receptors, downstream signaling molecules transduce this event within cells to mediate further events, including alteration of microtubule and actin cytoskeletal dynamics. Here, I review recent studies on semaphorin signaling in vertebrate neural circuit assembly, with the goal of highlighting how this diverse family of cues and receptors imparts exquisite specificity to neural complex connectivity. PMID:22685427

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

    PubMed

    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

  7. Automatic segmentation of vertebral arteries in CT angiography using combined circular and cylindrical model fitting

    NASA Astrophysics Data System (ADS)

    Lee, Min Jin; Hong, Helen; Chung, Jin Wook

    2014-03-01

    We propose an automatic vessel segmentation method of vertebral arteries in CT angiography using combined circular and cylindrical model fitting. First, to generate multi-segmented volumes, whole volume is automatically divided into four segments by anatomical properties of bone structures along z-axis of head and neck. To define an optimal volume circumscribing vertebral arteries, anterior-posterior bounding and side boundaries are defined as initial extracted vessel region. Second, the initial vessel candidates are tracked using circular model fitting. Since boundaries of the vertebral arteries are ambiguous in case the arteries pass through the transverse foramen in the cervical vertebra, the circle model is extended along z-axis to cylinder model for considering additional vessel information of neighboring slices. Finally, the boundaries of the vertebral arteries are detected using graph-cut optimization. From the experiments, the proposed method provides accurate results without bone artifacts and eroded vessels in the cervical vertebra.

  8. Toward understanding the evolution of vertebrate gene regulatory networks: comparative genomics and epigenomic approaches.

    PubMed

    Martinez-Morales, Juan R

    2016-07-01

    Vertebrates, as most animal phyla, originated >500 million years ago during the Cambrian explosion, and progressively radiated into the extant classes. Inferring the evolutionary history of the group requires understanding the architecture of the developmental programs that constrain the vertebrate anatomy. Here, I review recent comparative genomic and epigenomic studies, based on ChIP-seq and chromatin accessibility, which focus on the identification of functionally equivalent cis-regulatory modules among species. This pioneer work, primarily centered in the mammalian lineage, has set the groundwork for further studies in representative vertebrate and chordate species. Mapping of active regulatory regions across lineages will shed new light on the evolutionary forces stabilizing ancestral developmental programs, as well as allowing their variation to sustain morphological adaptations on the inherited vertebrate body plan. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. Vertebral column anomalies in Indo-Pacific and Atlantic humpback dolphins Sousa spp.

    PubMed

    Weir, Caroline R; Wang, John Y

    2016-08-09

    Conspicuous vertebral column abnormalities in humpback dolphins (genus Sousa) were documented for the first time during 3 photo-identification field studies of small populations in Taiwan, Senegal and Angola. Seven Taiwanese humpback dolphins S. chinensis taiwanensis with vertebral column anomalies (lordosis, kyphosis or scoliosis) were identified, along with 2 possible cases of vertebral osteomyelitis. There was evidence from several individuals photographed over consecutive years that the anomalies became more pronounced with age. Three Atlantic humpback dolphins S. teuszii were observed with axial deviations of the vertebral column (lordosis and kyphosis). Another possible case was identified in a calf, and 2 further animals were photographed with dorsal indents potentially indicative of anomalies. Vertebral column anomalies of humpback dolphins were predominantly evident in the lumbo-caudal region, but one Atlantic humpback dolphin had an anomaly in the cervico-thoracic region. Lordosis and kyphosis occurred simultaneously in several individuals. Apart from the described anomalies, all dolphins appeared in good health and were not obviously underweight or noticeably compromised in swim speed. This study presents the first descriptions of vertebral column anomalies in the genus Sousa. The causative factors for the anomalies were unknown in every case and are potentially diverse. Whether these anomalies result in reduced fitness of individuals or populations merits attention, as both the Taiwanese and Atlantic humpback dolphin are species of high conservation concern.

  10. Update of vertebral cementoplasty in porotic patients

    PubMed Central

    Masala, Salvatore; Muto, Mario

    2015-01-01

    Vertebroplasty (VP) is a percutaneous mini-invasive technique developed in the late 1980s as antalgic and stabilizing treatment in patients affected by symptomatic vertebral fracture due to porotic disease, traumatic injury and primary or secondary vertebral spine tumors. The technique consists of a simple metameric injection of an inert cement (poly-methyl-methacrylate, PMMA), through a needle by trans-peduncular, parapeduncular or trans-somatic approach obtaining a vertebral augmentation and stabilization effect associated with pain relief. The technique is simple and fast, and should be performed under fluoroscopy or CT guidance in order to obtain a good result with low complication rate. The aim of this paper is to illustrate the utility of VP, the indications-contraindications criteria, how to technically perform the technique using imaging guidance, and the results and complications of this treatment in patients affected by symptomatic vertebral compression fracture. PMID:26015527

  11. Innate immunity in vertebrates: an overview.

    PubMed

    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.

  12. Cervicobrachialgia with congenital vertebral anomalies and diastematomyelia.

    PubMed

    Roosen, N; De Moor, J

    1984-05-01

    A case of diastematomyelia in an adult female patient is reported. The relationship of the cervicobrachialgia, which was the presenting sign, to the diastematomyelia and the congenital vertebral anomalies is discussed.

  13. A Case of Aerococcus Urinae Vertebral Osteomyelitis

    PubMed Central

    Jerome, Michael; Slim, Jihad; Sison, Raymund; Marton, Randy

    2015-01-01

    Aerococcus urinae is an aerobic, alpha hemolytic gram positive coccus bacterium that grows in pairs or clusters. We report the first case of vertebral osteomyelitis due to A. urinae. This has not been previously reported in the literature. PMID:26069429

  14. [Vertebral osteomyelitis associated with epidural block].

    PubMed

    Carrillo Esper, R; Cruz-Bautista, I

    2001-01-01

    Infectious complications after epidural anesthesia are infrequent and the most common are epidural and subdural abscess. We report one rare case of vertebral osteomyelitus associated with an epidural catheter and review the literature.

  15. [Osteocyte-network in various vertebrates].

    PubMed

    Yamaguchi, Akira

    2012-05-01

    Since aquatic and land vertebrates live in different habitats,the morphology and function of bone might be greatly affected by the habitats of each vertebrate. We histologically investigated the bones of various vertebrates including teleost fishes, amphibians, reptiles, and mammals. Teleost fishes exhibited either bones contained many osteocytes (cellular bone) or bones have few osteocytes (acellular bone) . The development of osteocyte lacunocanalicular system in the cellular bone of the fish is poor compared to those in amphibians, reptiles, and mammals. Bones in Xenopus laevis, a freshwater species, exhibited well-developed lacunocanalicular systems as well as those in reptiles and mammals. These studies indicates that the osteocyte lacunocanalicular system differs between teleost fishes and land vertebrates, but this is not directly related to aquatic habitat.

  16. Evolution of Herbivory in Terrestrial Vertebrates

    NASA Astrophysics Data System (ADS)

    Sues, Hans-Dieter

    2000-08-01

    Although herbivory probably first appeared over 300 million years ago, it only became established as a common feeding strategy during Late Permian times. Subsequently, herbivory evolved in numerous lineages of terrestrial vertebrates, and the acquisition of this mode of feeding was frequently associated with considerable evolutionary diversification in those lineages. This book represents a comprehensive overview of the evolution of herbivory in land-dwelling amniote tetrapods in recent years. In Evolution of Herbivory in Terrestrial Vertebrates, leading experts review the evolutionary history and structural adaptations required for feeding on plants in the major groups of land-dwelling vertebrates, especially dinosaurs and ungulate mammals. As such, this volume will be the definitive reference source on this topic for evolutionary biologists and vertebrate paleontologists.

  17. Sleep and orexins in nonmammalian vertebrates.

    PubMed

    Volkoff, Hélène

    2012-01-01

    Although a precise definition of "sleep" has yet to be established, sleep-like behaviors have been observed in all animals studied to date including mammals and nonmammalian vertebrates. Orexins are hypothalamic neuropeptides that are involved in the regulation of many physiological functions, including feeding, thermoregulation, cardiovascular control, as well as the control of the sleep-wakefulness cycle. To date, the knowledge on the functions of orexins in nonmammalian vertebrates is still limited, but the similarity of the structures of orexins and their receptors among vertebrates suggest that they have similar conserved physiological functions. This review describes our current knowledge on sleep in nonmammalian vertebrates (birds, reptiles, amphibians, and fish) and the possible role of orexins in the regulation of their energy homeostasis and arousal states.

  18. RFamide Peptides in Early Vertebrate Development

    PubMed Central

    Sandvik, Guro Katrine; Hodne, Kjetil; Haug, Trude Marie; Okubo, Kataaki; Weltzien, Finn-Arne

    2014-01-01

    RFamides (RFa) are neuropeptides involved in many different physiological processes in vertebrates, such as reproductive behavior, pubertal activation of the reproductive endocrine axis, control of feeding behavior, and pain modulation. As research has focused mostly on their role in adult vertebrates, the possible roles of these peptides during development are poorly understood. However, the few studies that exist show that RFa are expressed early in development in different vertebrate classes, perhaps mostly associated with the central nervous system. Interestingly, the related peptide family of FMRFa has been shown to be important for brain development in invertebrates. In a teleost, the Japanese medaka, knockdown of genes in the Kiss system indicates that Kiss ligands and receptors are vital for brain development, but few other functional studies exist. Here, we review the literature of RFa in early vertebrate development, including the possible functional roles these peptides may play. PMID:25538682

  19. What is the general action of ghrelin for vertebrates? - comparisons of ghrelin's effects across vertebrates.

    PubMed

    Kaiya, Hiroyuki; Kangawa, Kenji; Miyazato, Mikiya

    2013-01-15

    Ten years and more passed since ghrelin was discovered. Various physiological actions of ghrelin have been documented in both mammalian and nonmammalian vertebrates. Do these actions have any commonality? In this review, we focused on several effects of ghrelin, and compared the effect across vertebrates. We would like to discuss possible general function of ghrelin in vertebrates. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Role of Transpedicular Percutaneous Vertebral Biopsy for Diagnosis of Pathology in Vertebral Compression Fractures

    PubMed Central

    Nadkarni, Sunil; Hardikar, Sharad Moreshwar; Hardikar, Madan Sharad

    2016-01-01

    Study Design Retrospective observational study. Purpose To identify the role of percutaneous vertebral biopsy in histopathological diagnosis of vertebral compression fractures and to identify the frequency of unexpected malignancy in vertebral compression fractures. Overview of Literature Vertebral compression fractures are common in the Indian population. Magnetic resonance imaging and nuclear imaging have some limitations in the diagnosis of definitive pathology of vertebral compression fractures. Therefore, histological confirmation is necessary for definitive diagnosis and to plan appropriate management for patient. Methods A retrospective observational study was conducted involving 84 patients who underwent percutaneous vertebral biopsy between 2010 and 2014. We performed C-arm guided percutaneous transpedicular core vertebral biopsy of vertebral compression fractures under combination of local anesthesia and intravenous conscious sedation. Results Sufficient biopsy material was obtained in 79 of the 84 cases. In the other five cases, biopsy material was not sufficient for reporting. Out of the 79 cases, osteoporotic pathology was detected in 69 patients, malignancy was detected in 8 patients and no pathology was found in 2 patients. Two patients with distant metastases to vertebra were identified. Primary spinal malignancy was detected in 6 patients (1 unsuspected plasmacytoma, 5 diagnosed malignancy preoperatively). So, the frequency of unsuspected malignancy of this study was 1.19% (1/84). None of the patients had any complications. Conclusions C-arm guided percutaneous transpedicular vertebral biopsy is useful in obtaining definitive histopathological diagnosis of vertebral compression fractures, especially in differentiating malignant and non-malignant vertebral compression fractures and helping plan appropriate management of patients. The rate of unexpected malignancy in vertebral compression fracture was 1.19%. PMID:27790322

  1. Vertebrate Cells Express Protozoan Antigen after Hybridization

    NASA Astrophysics Data System (ADS)

    Crane, Mark St. J.; Dvorak, James A.

    1980-04-01

    Epimastigotes, the invertebrate host stage of Trypanosoma cruzi, the protozoan parasite causing Chagas' disease in man, were fused with vertebrate cells by using polyethylene glycol. Hybrid cells were selected on the basis of T. cruzi DNA complementation of biochemical deficiencies in the vertebrate cells. Some clones of the hybrid cells expressed T. cruzi-specific antigen. It might be possible to use selected antigens obtained from the hybrids as vaccines for immunodiagnosis or for elucidation of the pathogenesis of Chagas' disease.

  2. Diagnosis and treatment of vertebral compression fractures.

    PubMed

    Dewar, Cherie

    2015-01-01

    A healthy spine is an integral part of an individual's overall well-being. The spinal column's essential role in physiological and neurological function can be compromised when disease or trauma causes a vertebra to compress under the body's weight, producing a vertebral compression fracture. This is a common ailment among adults older than 65 years of age, especially for those with low bone mass or osteoporosis. This article describes vertebral compression fractures, with a special emphasis on medical imaging.

  3. Percutaneous Vertebral Body Augmentation: An Updated Review

    PubMed Central

    Omidi-Kashani, Farzad

    2014-01-01

    There are many medical conditions like osteoporosis, tumor, or osteonecrosis that weaken the structural strength of the vertebral body and prone it to fracture. Percutaneous vertebral augmentation that is usually applied by polymethylmethacrylate is a relatively safe, effective, and long lasting procedure commonly performed in these situations. In this paper, we updated a review of biomechanics, indications, contraindications, surgical techniques, complications, and overall prognosis of these minimally invasive spinal procedures. PMID:25379561

  4. Cervical vertebral fusion with anterior meningocele

    PubMed Central

    Chavredakis, Emmanuel; Carter, David; Bhojak, Manesh; Jenkinson, Michael D; Clark, Simon R

    2015-01-01

    We present the first described case of cervical vertebral fusion associated with anterior meningocele and syringomyelia. A 45-year-old woman presented with minor trauma, and plain cervical spine radiographs highlighted a congenital deformity of the cervical vertebral bodies. She had a normal neurological examination; however, further imaging revealed a meningocele and syringomyelia. This case highlights the importance of thorough imaging investigation when presented with a congenital deformity in order to detect and prevent development of degenerative spinal cord pathologies. PMID:25923673

  5. Vertebral osteomyelitis: clinical features and diagnosis.

    PubMed

    Eren Gök, S; Kaptanoğlu, E; Celikbaş, A; Ergönül, O; Baykam, N; Eroğlu, M; Dokuzoğuz, B

    2014-10-01

    We aimed to describe clinical and diagnostic features of vertebral osteomyelitis for differential diagnosis and treatment. This is a prospective observational study performed between 2002 and 2012 in Ankara Numune Education and Research Hospital in Ankara, Turkey. All the patients with vertebral osteomyelitis were followed for from 6 months to 3 years. In total, 214 patients were included in the study, 113 out of 214 (53%) were female. Out of 214 patients, 96 (45%) had brucellar vertebral osteomyelitis (BVO), 63 (29%) had tuberculous vertebral osteomyelitis (TVO), and 55 (26%) had pyogenic vertebral osteomyelitis (PVO). Mean number of days between onset of symptoms and establishment of diagnosis was greater with the patients with TVO (266 days) than BVO (115 days) or PVO (151 days, p <0.001). In blood cultures, Brucella spp. were isolated from 35 of 96 BVO patients (35%). Among 55 PVO patients, the aetiological agent was isolated in 11 (20%) patients. For tuberculin skin test >15 mm, sensitivity was 0.66, specificity was 0.97, positive predictive value was 0.89, negative predictive value was 0.88, and receiver operating characteristics area was 0.8. Tuberculous and brucellar vertebral osteomyelitis remained the leading causes of vertebral osteomyelitis with delayed diagnosis. In differential diagnosis of vertebral osteomyelitis, consumption of unpasteurized cheese, dealing with husbandry, sweating, arthralgia, hepatomegaly, elevated alanine transaminase, and lumbar involvement in magnetic resonance imaging were found to be predictors of BVO, thoracic involvement in magnetic resonance imaging and tuberculin skin test > 15 mm were found to be predictors of TVO, and history of spinal surgery and leucocytosis were found to be predictors of PVO.

  6. Concomitant and previous osteoporotic vertebral fractures

    PubMed Central

    Lenski, Markus; Büser, Natalie; Scherer, Michael

    2017-01-01

    Background and purpose Patients with osteoporosis who present with an acute onset of back pain often have multiple fractures on plain radiographs. Differentiation of an acute osteoporotic vertebral fracture (AOVF) from previous fractures is difficult. The aim of this study was to investigate the incidence of concomitant AOVFs and previous OVFs in patients with symptomatic AOVFs, and to identify risk factors for concomitant AOVFs. Patients and methods This was a prospective epidemiological study based on the Registry of Pathological Osteoporotic Vertebral Fractures (REPAPORA) with 1,005 patients and 2,874 osteoporotic vertebral fractures, which has been running since February 1, 2006. Concomitant fractures are defined as at least 2 acute short-tau inversion recovery (STIR-) positive vertebral fractures that happen concomitantly. A previous fracture is a STIR-negative fracture at the time of initial diagnostics. Logistic regression was used to examine the influence of various variables on the incidence of concomitant fractures. Results More than 99% of osteoporotic vertebral fractures occurred in the thoracic and lumbar spine. The incidence of concomitant fractures at the time of first patient contact was 26% and that of previous fractures was 60%. The odds ratio (OR) for concomitant fractures decreased with a higher number of previous fractures (OR =0.86; p = 0.03) and higher dual-energy X-ray absorptiometry T-score (OR =0.72; p = 0.003). Interpretation Concomitant and previous osteoporotic vertebral fractures are common. Risk factors for concomitant fractures are a low T-score and a low number of previous vertebral fractures in cases of osteoporotic vertebral fracture. An MRI scan of the the complete thoracic and lumbar spine with STIR sequence reduces the risk of under-diagnosis and under-treatment. PMID:28056595

  7. Radiotherapy in the treatment of vertebral hemangiomas

    SciTech Connect

    Faria, S.L.; Schlupp, W.R.; Chiminazzo, H. Jr.

    1985-02-01

    Symptomatic vertebral hemangiomas are not common. Although radiotherapy has been used as treatment, the data are sparse concerning total dose, fractionation and results. The authors report nine patients with vertebral hemangioma treated with 3000-4000 rad, 200 rad/day, 5 fractions per week, followed from 6 to 62 months. Seventy-seven percent had complete or almost complete disappearance of the symptoms. Radiotherapy schedules are discussed.

  8. Quantitative anatomy of vertebral artery groove on the posterior arch of atlas in relation to spinal surgical procedures.

    PubMed

    Gupta, Tulika

    2008-05-01

    The location of the vertebral artery on a groove on the superior surface of the posterior arch of atlas makes it vulnerable to injury during surgical procedures in this region. Knowledge of the quantitative anatomy of the vertebral artery groove is therefore necessary. In 55 dry adult atlas vertebrae, the distance of the medial edges of the vertebral artery groove were measured from the posterior midline at both the inner and outer cortices of the posterior arch of atlas. In addition, the distance between the vertebral artery grooves on either side as well as the length of the vertebral artery groove was also measured. It was found that a minimum of 1.5 cm of the posterior arch could be safely exposed at both the outer and inner cortices. In addition, with mobilization of the vertebral artery from its groove on both the sides, an additional 1 cm of posterior arch could be exposed on either side. Exposure of the posterior arch of the atlas is an important step in surgical procedures for treatment of diverse conditions of the upper spinal cord and foramen magnum region. Injury to the vertebral artery in its position on the vertebral groove may lead to disastrous complications. The present study reveals that the neurosurgeon can safely expose up to 3.5 cm of the posterior arch of atlas and knowledge of this anatomic fact may help in planning surgical approaches.

  9. Prevalence of osteoporotic vertebral fracture in Spanish women over age 45.

    PubMed

    Herrera, Antonio; Mateo, Jesús; Gil-Albarova, Jorge; Lobo-Escolar, Antonio; Artigas, José M; López-Prats, Fernando; Mesa, Manuel; Ibarz, Elena; Gracia, Luis

    2015-03-01

    The aim of this work is to study the prevalence of osteoporotic vertebral fractures in Spanish women over 45 years of age, based on the selection of a nationwide sample. An observational, cross-sectional, multicenter study was conducted during 2006, in all of Spain's regions. The sample analyzed was of 5000 individuals, representative of the female population over age 45 in Spain. A questionnaire was used to determine which factors are most often associated with vertebral fractures. We also assessed whether the Prevalent Vertebral Fracture Index, proposed by Vogt, is useful in indicating a possible osteoporotic vertebral fracture. Five hundred orthopedic surgeons, from various Spanish regions, were trained in different aspects of the study: inclusion and exclusion criteria, management of the risk factor questionnaire, and implementation of the Vogt questionnaire. The number of fracture cases was 1549 (31.79%). 528 Women (34.08%) had a single vertebral fracture, and 1021 (65.92%) had multiple vertebral fractures. The following factors were statistically significantly associated with vertebral fracture: age, late menarche, early menopause, diabetes mellitus, hyperparathyroidism, rheumatoid arthritis, height loss, daily physical activity, corticosteroid therapy, personal history of osteoporotic fracture and previous diagnosis of osteoporosis. The differences in Vogt score according to age and fracture status were statistically significant. The conclusion of the study is that vertebral osteoporotic fracture in the female Spanish population is frequent. The high prevalence in the Spanish population older than 60 years is probably related to malnutrition in the period from 1936 to 1952. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Complete sequence of a sea lamprey (Petromyzon marinus) mitochondrial genome: Early establishment of the vertebrate genome organization

    SciTech Connect

    Lee, W.J.; Kocher, T.D.

    1995-02-01

    The complete nucleotide sequence of a sea lamprey (Petromyzon marinus) mitochondrial genome has been determined. The lamprey genome is 16,201 bp in length and contains genes for 13 proteins, two rRNAs, 22 tRNAs and two major noncoding regions. The order and transcriptional polarities of protein-coding genes are basically identical to those of other chordate mtDNAs, demonstrating that the common mitochondrial gene organization of vertebrates was established at early stage of vertebrate evolution. The two major noncoding regions are separated by two tRNA genes. The first region probably functions as the control region because it contains distinctive conserved sequence blocks (CSB-II and III) common to other vertebrate control regions. The central conserved domain observed in other vertebrate control regions is not found in the lamprey, suggesting that it is a recently evolved functional domain in vertebrates. Noncoding segments are not found in the expected position of the origin of replication for the second strand, suggesting either that one of the tRNA genes has a dual function or that the second noncoding region may function as the second-strand origin. The base composition at the wobble positions of fourfold degenerate codon families is highly biased toward thymine (32.7%). Values of GC- and AT-skew are typical of vertebrate mitochondrial genomes. 38 refs., 11 figs., 5 tabs.

  11. Complete Sequence of a Sea Lamprey (Petromyzon Marinus) Mitochondrial Genome: Early Establishment of the Vertebrate Genome Organization

    PubMed Central

    Lee, W. J.; Kocher, T. D.

    1995-01-01

    The complete nucleotide sequence of a sea lamprey (Petromyzon marinus) mitochondrial genome has been determined. The lamprey genome is 16,201 bp in length and contains genes for 13 proteins, two rRNAs, 22 tRNAs and two major noncoding regions. The order and transcriptional polarities of protein-coding genes are basically identical to those of other chordate mtDNAs, demonstrating that the common mitochondrial gene organization of vertebrates was established at an early stage of vertebrate evolution. The two major noncoding regions are separated by two tRNA genes. The first region probably functions as the control region because it contains distinctive conserved sequence blocks (CSB-II and III) common to other vertebrate control regions. The central conserved domain observed in other vertebrate control regions is not found in the lamprey, suggesting that it is a recently evolved functional domain in vertebrates. Noncoding segments are not found in the expected position of the origin of replication for the second strand, suggesting either that one of the tRNA genes has a dual function or that the second noncoding region may function as the second-strand origin. The base composition at the wobble positions of fourfold degenerate codon families is highly biased toward thymine (32.7%). Values of GC-and AT-skew are typical of vertebrate mitochondrial genomes.genomes. PMID:7713438

  12. Vertebral degenerative disc disease severity evaluation using random forest classification

    NASA Astrophysics Data System (ADS)

    Munoz, Hector E.; Yao, Jianhua; Burns, Joseph E.; Pham, Yasuyuki; Stieger, James; Summers, Ronald M.

    2014-03-01

    Degenerative disc disease (DDD) develops in the spine as vertebral discs degenerate and osseous excrescences or outgrowths naturally form to restabilize unstable segments of the spine. These osseous excrescences, or osteophytes, may progress or stabilize in size as the spine reaches a new equilibrium point. We have previously created a CAD system that detects DDD. This paper presents a new system to determine the severity of DDD of individual vertebral levels. This will be useful to monitor the progress of developing DDD, as rapid growth may indicate that there is a greater stabilization problem that should be addressed. The existing DDD CAD system extracts the spine from CT images and segments the cortical shell of individual levels with a dual-surface model. The cortical shell is unwrapped, and is analyzed to detect the hyperdense regions of DDD. Three radiologists scored the severity of DDD of each disc space of 46 CT scans. Radiologists' scores and features generated from CAD detections were used to train a random forest classifier. The classifier then assessed the severity of DDD at each vertebral disc level. The agreement between the computer severity score and the average radiologist's score had a quadratic weighted Cohen's kappa of 0.64.

  13. Upstream ORFs are prevalent translational repressors in vertebrates.

    PubMed

    Johnstone, Timothy G; Bazzini, Ariel A; Giraldez, Antonio J

    2016-04-01

    Regulation of gene expression is fundamental in establishing cellular diversity and a target of natural selection. Untranslated mRNA regions (UTRs) are key mediators of post-transcriptional regulation. Previous studies have predicted thousands of ORFs in 5'UTRs, the vast majority of which have unknown function. Here, we present a systematic analysis of the translation and function of upstream open reading frames (uORFs) across vertebrates. Using high-resolution ribosome footprinting, we find that (i)uORFs are prevalent within vertebrate transcriptomes, (ii) the majority show signatures of active translation, and (iii)uORFs act as potent regulators of translation and RNA levels, with a similar magnitude to miRNAs. Reporter experiments reveal clear repression of downstream translation by uORFs/oORFs. uORF number, intercistronic distance, overlap with the CDS, and initiation context most strongly influence translation. Evolution has targeted these features to favor uORFs amenable to regulation over constitutively repressive uORFs/oORFs. Finally, we observe that the regulatory potential of uORFs on individual genes is conserved across species. These results provide insight into the regulatory code within mRNA leader sequences and their capacity to modulate translation across vertebrates. © 2016 The Authors.

  14. Quantitative vertebral compression fracture evaluation using a height compass

    NASA Astrophysics Data System (ADS)

    Yao, Jianhua; Burns, Joseph E.; Wiese, Tatjana; Summers, Ronald M.

    2012-03-01

    Vertebral compression fractures can be caused by even minor trauma in patients with pathological conditions such as osteoporosis, varying greatly in vertebral body location and compression geometry. The location and morphology of the compression injury can guide decision making for treatment modality (vertebroplasty versus surgical fixation), and can be important for pre-surgical planning. We propose a height compass to evaluate the axial plane spatial distribution of compression injury (anterior, posterior, lateral, and central), and distinguish it from physiologic height variations of normal vertebrae. The method includes four steps: spine segmentation and partition, endplate detection, height compass computation and compression fracture evaluation. A height compass is computed for each vertebra, where the vertebral body is partitioned in the axial plane into 17 cells oriented about concentric rings. In the compass structure, a crown-like geometry is produced by three concentric rings which are divided into 8 equal length arcs by rays which are subtended by 8 common central angles. The radius of each ring increases multiplicatively, with resultant structure of a central node and two concentric surrounding bands of cells, each divided into octants. The height value for each octant is calculated and plotted against octants in neighboring vertebrae. The height compass shows intuitive display of the height distribution and can be used to easily identify the fracture regions. Our technique was evaluated on 8 thoraco-abdominal CT scans of patients with reported compression fractures and showed statistically significant differences in height value at the sites of the fractures.

  15. Risk of vertebral compression fractures in multiple myeloma patients

    PubMed Central

    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. MDCT-based FE models were developed from the in vitro vertebrae samples and were then applied to the in vivo vertebrae segments of MM patients (n = 4) after validation. Predicted fracture load using FE models correlated significantly with experimentally measured failure load (r = 0.85, P < 0.001). Interestingly, an erratic behavior was observed in patients with fractures (n = 2) and a more gradual change in FE-predicted strength values in patients without fractures (n = 2). Severe geometric deformations were also observed in models that have already attained fractures. Since BMD is not a reliable parameter for fracture risk prediction in MM subjects, it is necessary to use advanced tools such as FE analysis to predict individual fracture risk. If peaks are observed between adjacent segments in an MM patient, it can be safe to conclude that the spine is experiencing regions of structural instability. Such an FE visualization may have therapeutic consequences to prevent MM associated vertebral fractures. PMID:28079810

  16. CRDB: Database of Chemosensory Receptor Gene Families in Vertebrate

    PubMed Central

    Wu, Xiaoli; Zhong, Yang

    2012-01-01

    Chemosensory receptors (CR) are crucial for animals to sense the environmental changes and survive on earth. The emergence of whole-genome sequences provides us an opportunity to identify the entire CR gene repertoires. To completely gain more insight into the evolution of CR genes in vertebrates, we identified the nearly all CR genes in 25 vertebrates using homology-based approaches. Among these CR gene repertoires, nearly half of them were identified for the first time in those previously uncharacterized species, such as the guinea pig, giant panda and elephant, etc. Consistent with previous findings, we found that the numbers of CR genes vary extensively among different species, suggesting an extreme form of ‘birth-and-death’ evolution. For the purpose of facilitating CR gene analysis, we constructed a database with the goals to provide a resource for CR genes annotation and a web tool for exploring their evolutionary patterns. Besides a search engine for the gene extraction from a specific chromosome region, an easy-to-use phylogenetic analysis tool was also provided to facilitate online phylogeny study of CR genes. Our work can provide a rigorous platform for further study on the evolution of CR genes in vertebrates. PMID:22393364

  17. Evolution and development of interhemispheric connections in the vertebrate forebrain

    PubMed Central

    Suárez, Rodrigo; Gobius, Ilan; Richards, Linda J.

    2014-01-01

    Axonal connections between the left and right sides of the brain are crucial for bilateral integration of lateralized sensory, motor, and associative functions. Throughout vertebrate species, forebrain commissures share a conserved developmental plan, a similar position relative to each other within the brain and similar patterns of connectivity. However, major events in the evolution of the vertebrate brain, such as the expansion of the telencephalon in tetrapods and the origin of the six-layered isocortex in mammals, resulted in the emergence and diversification of new commissural routes. These new interhemispheric connections include the pallial commissure, which appeared in the ancestors of tetrapods and connects the left and right sides of the medial pallium (hippocampus in mammals), and the corpus callosum, which is exclusive to eutherian (placental) mammals and connects both isocortical hemispheres. A comparative analysis of commissural systems in vertebrates reveals that the emergence of new commissural routes may have involved co-option of developmental mechanisms and anatomical substrates of preexistent commissural pathways. One of the embryonic regions of interest for studying these processes is the commissural plate, a portion of the early telencephalic midline that provides molecular specification and a cellular scaffold for the development of commissural axons. Further investigations into these embryonic processes in carefully selected species will provide insights not only into the mechanisms driving commissural evolution, but also regarding more general biological problems such as the role of developmental plasticity in evolutionary change. PMID:25071525

  18. Homeotic effects, somitogenesis and the evolution of vertebral numbers in recent and fossil amniotes.

    PubMed

    Müller, Johannes; Scheyer, Torsten M; Head, Jason J; Barrett, Paul M; Werneburg, Ingmar; Ericson, Per G P; Pol, Diego; Sánchez-Villagra, Marcelo R

    2010-02-02

    The development of distinct regions in the amniote vertebral column results from somite formation and Hox gene expression, with the adult morphology displaying remarkable variation among lineages. Mammalian regionalization is reportedly very conservative or even constrained, but there has been no study investigating vertebral count variation across Amniota as a whole, undermining attempts to understand the phylogenetic, ecological, and developmental factors affecting vertebral column variation. Here, we show that the mammalian (synapsid) and reptilian lineages show early in their evolutionary histories clear divergences in axial developmental plasticity, in terms of both regionalization and meristic change, with basal synapsids sharing the conserved axial configuration of crown mammals, and basal reptiles demonstrating the plasticity of extant taxa. We conducted a comprehensive survey of presacral vertebral counts across 436 recent and extinct amniote taxa. Vertebral counts were mapped onto a generalized amniote phylogeny as well as individual ingroup trees, and ancestral states were reconstructed by using squared-change parsimony. We also calculated the relationship between presacral and cervical numbers to infer the relative influence of homeotic effects and meristic changes and found no correlation between somitogenesis and Hox-mediated regionalization. Although conservatism in presacral numbers characterized early synapsid lineages, in some cases reptiles and synapsids exhibit the same developmental innovations in response to similar selective pressures. Conversely, increases in body mass are not coupled with meristic or homeotic changes, but mostly occur in concert with postembryonic somatic growth. Our study highlights the importance of fossils in large-scale investigations of evolutionary developmental processes.

  19. Homeotic effects, somitogenesis and the evolution of vertebral numbers in recent and fossil amniotes

    PubMed Central

    Müller, Johannes; Scheyer, Torsten M.; Head, Jason J.; Barrett, Paul M.; Werneburg, Ingmar; Ericson, Per G. P.; Pol, Diego; Sánchez-Villagra, Marcelo R.

    2010-01-01

    The development of distinct regions in the amniote vertebral column results from somite formation and Hox gene expression, with the adult morphology displaying remarkable variation among lineages. Mammalian regionalization is reportedly very conservative or even constrained, but there has been no study investigating vertebral count variation across Amniota as a whole, undermining attempts to understand the phylogenetic, ecological, and developmental factors affecting vertebral column variation. Here, we show that the mammalian (synapsid) and reptilian lineages show early in their evolutionary histories clear divergences in axial developmental plasticity, in terms of both regionalization and meristic change, with basal synapsids sharing the conserved axial configuration of crown mammals, and basal reptiles demonstrating the plasticity of extant taxa. We conducted a comprehensive survey of presacral vertebral counts across 436 recent and extinct amniote taxa. Vertebral counts were mapped onto a generalized amniote phylogeny as well as individual ingroup trees, and ancestral states were reconstructed by using squared-change parsimony. We also calculated the relationship between presacral and cervical numbers to infer the relative influence of homeotic effects and meristic changes and found no correlation between somitogenesis and Hox-mediated regionalization. Although conservatism in presacral numbers characterized early synapsid lineages, in some cases reptiles and synapsids exhibit the same developmental innovations in response to similar selective pressures. Conversely, increases in body mass are not coupled with meristic or homeotic changes, but mostly occur in concert with postembryonic somatic growth. Our study highlights the importance of fossils in large-scale investigations of evolutionary developmental processes. PMID:20080660

  20. The origins of colour vision in vertebrates.

    PubMed

    Collin, Shaun P; Trezise, Ann E O

    2004-07-01

    The capacity for colour vision is mediated by the comparison of the signal intensities from photoreceptors of two or more types that differ in spectral sensitivity. Morphological, physiological and molecular analyses of the retina in an agnathan (jawless) fish, the lamprey Geotria australis, may hold important clues to the origins of colour vision in vertebrates. Lampreys are extant representatives of an ancient group of vertebrates, the origins of which are thought to date back to at least the early Cambrian, approximately 540 million years ago. G. australis possesses five photoreceptor types, each with cone-like ultrastructural features and different spectral sensitivities. Recent molecular genetic studies have also revealed that five visual pigment (opsin) genes are expressed in the retina, each of which is orthologous to the major classes of vertebrate opsin genes. These findings reveal that multiple opsin genes originated very early in vertebrate evolution, prior to the separation of the jawed and jawless vertebrate lineages, thereby providing the genetic basis for colour vision in all vertebrates.

  1. Retroviral Diversity and Distribution in Vertebrates

    PubMed Central

    Herniou, Elisabeth; Martin, Joanne; Miller, Karen; Cook, James; Wilkinson, Mark; Tristem, Michael

    1998-01-01

    We used the PCR to screen for the presence of endogenous retroviruses within the genomes of 18 vertebrate orders across eight classes, concentrating on reptilian, amphibian, and piscine hosts. Thirty novel retroviral sequences were isolated and characterized by sequencing approximately 1 kb of their encoded protease and reverse transcriptase genes. Isolation of novel viruses from so many disparate hosts suggests that retroviruses are likely to be ubiquitous within all but the most basal vertebrate classes and, furthermore, gives a good indication of the overall retroviral diversity within vertebrates. Phylogenetic analysis demonstrated that viruses clustering with (but not necessarily closely related to) the spumaviruses and murine leukemia viruses are widespread and abundant in vertebrate genomes. In contrast, we were unable to identify any viruses from hosts outside of mammals and birds which grouped with the other five currently recognized retroviral genera: the lentiviruses, human T-cell leukemia-related viruses, avian leukemia virus-related retroviruses, type D retroviruses, and mammalian type B retroviruses. There was also some indication that viruses isolated from individual vertebrate classes tended to cluster together in phylogenetic reconstructions. This implies that the horizontal transmission of at least some retroviruses, between some vertebrate classes, occurs relatively infrequently. It is likely that many of the retroviral sequences described here are distinct enough from those of previously characterized viruses to represent novel retroviral genera. PMID:9621058

  2. Evolution and development of the vertebrate neck

    PubMed Central

    Ericsson, Rolf; Knight, Robert; Johanson, Zerina

    2013-01-01

    Muscles of the vertebrate neck include the cucullaris and hypobranchials. Although a functional neck first evolved in the lobe-finned fishes (Sarcopterygii) with the separation of the pectoral/shoulder girdle from the skull, the neck muscles themselves have a much earlier origin among the vertebrates. For example, lampreys possess hypobranchial muscles, and may also possess the cucullaris. Recent research in chick has established that these two muscles groups have different origins, the hypobranchial muscles having a somitic origin but the cucullaris muscle deriving from anterior lateral plate mesoderm associated with somites 1–3. Additionally, the cucullaris utilizes genetic pathways more similar to the head than the trunk musculature. Although the latter results are from experiments in the chick, cucullaris homologues occur in a variety of more basal vertebrates such as the sharks and zebrafish. Data are urgently needed from these taxa to determine whether the cucullaris in these groups also derives from lateral plate mesoderm or from the anterior somites, and whether the former or the latter represent the basal vertebrate condition. Other lateral plate mesoderm derivatives include the appendicular skeleton (fins, limbs and supporting girdles). If the cucullaris is a definitive lateral plate-derived structure it may have evolved in conjunction with the shoulder/limb skeleton in vertebrates and thereby provided a greater degree of flexibility to the heads of predatory vertebrates. PMID:22697305

  3. Vertebral deformities identified by vertebral fracture assessment: associations with clinical characteristics and bone mineral density.

    PubMed

    Jacobs-Kosmin, Dana; Sandorfi, Nora; Murray, Heather; Abruzzo, John L

    2005-01-01

    Whether vertebral fractures identified on radiographs are painful or not, they are associated with increased morbidity and mortality. Vertebral fractures on X-rays correlate with low bone mineral density (BMD) at the spine and hip in addition to several clinical characteristics. Evidence suggests that vertebral deformities detected by X-ray and by vertebral fracture assessment (VFA) show good agreement. We examined the relationship between VFA-detected vertebral deformities and patient characteristics as well as BMD by analyzing the records of 432 patients who had undergone dual-energy X-ray absorptiometry (DXA) scans with VFA. Patients' demographic data and T-scores were obtained from patient questionnaires and DXA scans. We categorized vertebral deformities by type and severity. Patients with vertebral deformities were significantly older and more likely to report a history of fracture after childhood. Significantly more estrogen use was reported in patients without deformity. Those with deformities had significantly lower T-scores at the femoral neck and total hip but not at the spine. Increased severity and number of deformities correlated with lower T-scores at the total hip and femoral neck but not the spine. In conclusion, vertebral deformities detected by VFA, like those on X-ray, correlate with both clinical characteristics and reduced bone mass at the hip. These relationships, in addition to rapid performance, convenience, and minimal radiation exposure, indicate VFA-detected vertebral deformities are a valuable adjunct in identifying patients in need of additional evaluation and treatment.

  4. Evolution of the structure and function of the vertebrate tongue.

    PubMed

    Iwasaki, Shin-ichi

    2002-07-01

    Studies of the comparative morphology of the tongues of living vertebrates have revealed how variations in the morphology and function of the organ might be related to evolutional events. The tongue, which plays a very important role in food intake by vertebrates, exhibits significant morphological variations that appear to represent adaptation to the current environmental conditions of each respective habitat. This review examines the fundamental importance of morphology in the evolution of the vertebrate tongue, focusing on the origin of the tongue and on the relationship between morphology and environmental conditions. Tongues of various extant vertebrates, including those of amphibians, reptiles, birds and mammals, were analysed in terms of gross anatomy and microanatomy by light microscopy and by scanning and transmission electron microscopy. Comparisons of tongue morphology revealed a relationship between changes in the appearance of the tongue and changes in habitat, from a freshwater environment to a terrestrial environment, as well as a relationship between the extent of keratinization of the lingual epithelium and the transition from a moist or wet environment to a dry environment. The lingual epithelium of amphibians is devoid of keratinization while that of reptilians is keratinized to different extents. Reptiles live in a variety of habitats, from seawater to regions of high temperature and very high or very low humidity. Keratinization of the lingual epithelium is considered to have been acquired concomitantly with the evolution of amniotes. The variations in the extent of keratinization of the lingual epithelium, which is observed between various amniotes, appear to be secondary, reflecting the environmental conditions of different species.

  5. Evolution of the structure and function of the vertebrate tongue

    PubMed Central

    Iwasaki, Shin-ichi

    2002-01-01

    Abstract Studies of the comparative morphology of the tongues of living vertebrates have revealed how variations in the morphology and function of the organ might be related to evolutional events. The tongue, which plays a very important role in food intake by vertebrates, exhibits significant morphological variations that appear to represent adaptation to the current environmental conditions of each respective habitat. This review examines the fundamental importance of morphology in the evolution of the vertebrate tongue, focusing on the origin of the tongue and on the relationship between morphology and environmental conditions. Tongues of various extant vertebrates, including those of amphibians, reptiles, birds and mammals, were analysed in terms of gross anatomy and microanatomy by light microscopy and by scanning and transmission electron microscopy. Comparisons of tongue morphology revealed a relationship between changes in the appearance of the tongue and changes in habitat, from a freshwater environment to a terrestrial environment, as well as a relationship between the extent of keratinization of the lingual epithelium and the transition from a moist or wet environment to a dry environment. The lingual epithelium of amphibians is devoid of keratinization while that of reptilians is keratinized to different extents. Reptiles live in a variety of habitats, from seawater to regions of high temperature and very high or very low humidity. Keratinization of the lingual epithelium is considered to have been acquired concomitantly with the evolution of amniotes. The variations in the extent of keratinization of the lingual epithelium, which is observed between various amniotes, appear to be secondary, reflecting the environmental conditions of different species. PMID:12171472

  6. Development and evolution of the vertebrate primary mouth

    PubMed Central

    Soukup, Vladimír; Horácek, Ivan; Cerny, Robert

    2013-01-01

    The vertebrate oral region represents a key interface between outer and inner environments, and its structural and functional design is among the limiting factors for survival of its owners. Both formation of the respective oral opening (primary mouth) and establishment of the food-processing apparatus (secondary mouth) require interplay between several embryonic tissues and complex embryonic rearrangements. Although many aspects of the secondary mouth formation, including development of the jaws, teeth or taste buds, are known in considerable detail, general knowledge about primary mouth formation is regrettably low. In this paper, primary mouth formation is reviewed from a comparative point of view in order to reveal its underestimated morphogenetic diversity among, and also within, particular vertebrate clades. In general, three main developmental modes were identified. The most common is characterized by primary mouth formation via a deeply invaginated ectodermal stomodeum and subsequent rupture of the bilaminar oral membrane. However, in salamander, lungfish and also in some frog species, the mouth develops alternatively via stomodeal collar formation contributed both by the ecto- and endoderm. In ray-finned fishes, on the other hand, the mouth forms via an ectoderm wedge and later horizontal detachment of the initially compressed oral epithelia with probably a mixed germ-layer derivation. A very intriguing situation can be seen in agnathan fishes: whereas lampreys develop their primary mouth in a manner similar to the most common gnathostome pattern, hagfishes seem to undergo a unique oropharyngeal morphogenesis when compared with other vertebrates. In discussing the early formative embryonic correlates of primary mouth formation likely to be responsible for evolutionary–developmental modifications of this area, we stress an essential role of four factors: first, positioning and amount of yolk tissue; closely related to, second, endoderm formation during

  7. Vascular Plant and Vertebrate Inventory of Tuzigoot National Monument

    USGS Publications Warehouse

    Powell, Brian F.; Albrecht, E.W.; Halvorson, William Lee; Schmidt, Cecilia A.; Anning, P.; Docherty, K.

    2005-01-01

    Executive Summary From 2002 to 2004, we surveyed for plants and vertebrates (amphibians, reptiles, birds, and mammals) at Tuzigoot National Monument (NM) and adjacent areas in Arizona. This was the first effort of its kind in the area and was part of a larger effort to inventory vascular plants and vertebrates in eight National Park Service units in Arizona and New Mexico. In addition to our own surveys, we also compiled a complete list of species that have been found by previous studies. We found 330 species, including 142 that had not previously been recorded at the monument (Table 1). We found 39 species of non-native plants, 11 non-native fishes, three non-native birds, and one non-native species each of amphibian and mammal. Based on our work and that of others, there have been 597 species of plants and vertebrates found at the monument. The bird community at the monument had the highest species richness of any national park unit in central and southern Arizona. We found all other taxa to have intermediate species richness compared to other park units in the region. This extraordinary species richness observed for birds, as well as for some other taxa, is due primarily to Tavasci Marsh and the Verde River, two critical sources of perennial water, which provide habitat for many regionally rare or uncommon species. The location of the monument at the northern edge of the Sonoran Desert and at the southern edge of the Mogollon Rim also plays an important role in determining the distribution and community composition of the plant and vertebrate communities. Based on our findings, we believe the high number of non-native species, especially fish and plants, should be of particular management concern. We detail other management challenges, most notably the rapid increase in housing and associated commercial development near the monument, which will continue to impact the plant and vertebrate communities. Based on our data and a review of past studies, we believe the

  8. Development and evolution of the vertebrate primary mouth.

    PubMed

    Soukup, Vladimír; Horácek, Ivan; Cerny, Robert

    2013-01-01

    The vertebrate oral region represents a key interface between outer and inner environments, and its structural and functional design is among the limiting factors for survival of its owners. Both formation of the respective oral opening (primary mouth) and establishment of the food-processing apparatus (secondary mouth) require interplay between several embryonic tissues and complex embryonic rearrangements. Although many aspects of the secondary mouth formation, including development of the jaws, teeth or taste buds, are known in considerable detail, general knowledge about primary mouth formation is regrettably low. In this paper, primary mouth formation is reviewed from a comparative point of view in order to reveal its underestimated morphogenetic diversity among, and also within, particular vertebrate clades. In general, three main developmental modes were identified. The most common is characterized by primary mouth formation via a deeply invaginated ectodermal stomodeum and subsequent rupture of the bilaminar oral membrane. However, in salamander, lungfish and also in some frog species, the mouth develops alternatively via stomodeal collar formation contributed both by the ecto- and endoderm. In ray-finned fishes, on the other hand, the mouth forms via an ectoderm wedge and later horizontal detachment of the initially compressed oral epithelia with probably a mixed germ-layer derivation. A very intriguing situation can be seen in agnathan fishes: whereas lampreys develop their primary mouth in a manner similar to the most common gnathostome pattern, hagfishes seem to undergo a unique oropharyngeal morphogenesis when compared with other vertebrates. In discussing the early formative embryonic correlates of primary mouth formation likely to be responsible for evolutionary-developmental modifications of this area, we stress an essential role of four factors: first, positioning and amount of yolk tissue; closely related to, second, endoderm formation during

  9. Vertebrate ancient-long opsin has molecular properties intermediate between those of vertebrate and invertebrate visual pigments.

    PubMed

    Sato, Keita; Yamashita, Takahiro; Ohuchi, Hideyo; Shichida, Yoshinori

    2011-12-06

    VA/VAL opsin is one of the four kinds of nonvisual opsins that are closely related to vertebrate visual pigments in the phylogenetic tree of opsins. Previous studies indicated that among these opsins, parapinopsin and pinopsin exhibit molecular properties similar to those of invertebrate bistable visual pigments and vertebrate visual pigments, respectively. Here we show that VA/VAL opsin exhibits molecular properties intermediate between those of parapinopsin and pinopsin. VAL opsin from Xenopus tropicalis was expressed in cultured cells, and the pigment with an absorption maximum at 501 nm was reconstituted by incubation with 11-cis-retinal. Light irradiation of this pigment caused cis-to-trans isomerization of the chromophore to form a state having an absorption maximum in the visible region. This state has the ability to activate Gi and Gt types of G proteins. Therefore, the active state of VAL opsin is a visible light-absorbing intermediate, which probably has a protonated retinylidene Schiff base as its chromophore, like the active state of parapinopsin. However, this state was apparently photoinsensitive and did not show reverse reaction to the original pigment, unlike the active state of parapinopsin, and instead similar to that of pinopsin. Furthermore, the Gi activation efficiency of VAL opsin was between those of pinopsin and parapinopsin. Thus, the molecular properties of VA/VAL opsin give insights into the mechanism of conversion of the molecular properties from invertebrate to vertebrate visual pigments.

  10. Evidence for Natural Selection in Nucleotide Content Relationships Based on Complete Mitochondrial Genomes: Strong Effect of Guanine Content on Separation between Terrestrial and Aquatic Vertebrates.

    PubMed

    Sorimachi, Kenji; Okayasu, Teiji

    2015-01-01

    The complete vertebrate mitochondrial genome consists of 13 coding genes. We used this genome to investigate the existence of natural selection in vertebrate evolution. From the complete mitochondrial genomes, we predicted nucleotide contents and then separated these values into coding and non-coding regions. When nucleotide contents of a coding or non-coding region were plotted against the nucleotide content of the complete mitochondrial genomes, we obtained linear regression lines only between homonucleotides and their analogs. On every plot using G or A content purine, G content in aquatic vertebrates was higher than that in terrestrial vertebrates, while A content in aquatic vertebrates was lower than that in terrestrial vertebrates. Based on these relationships, vertebrates were separated into two groups, terrestrial and aquatic. However, using C or T content pyrimidine, clear separation between these two groups was not obtained. The hagfish (Eptatretus burgeri) was further separated from both terrestrial and aquatic vertebrates. Based on these results, nucleotide content relationships predicted from the complete vertebrate mitochondrial genomes reveal the existence of natural selection based on evolutionary separation between terrestrial and aquatic vertebrate groups. In addition, we propose that separation of the two groups might be linked to ammonia detoxification based on high G and low A contents, which encode Glu rich and Lys poor proteins.

  11. Spatially Explicit Trends in the Global Conservation Status of Vertebrates

    PubMed Central

    Rodrigues, Ana S. L.; Brooks, Thomas M.; Butchart, Stuart H. M.; Chanson, Janice; Cox, Neil; Hoffmann, Michael; Stuart, Simon N.

    2014-01-01

    The world's governments have committed to preventing the extinction of threatened species and improving their conservation status by 2020. However, biodiversity is not evenly distributed across space, and neither are the drivers of its decline, and so different regions face very different challenges. Here, we quantify the contribution of regions and countries towards recent global trends in vertebrate conservation status (as measured by the Red List Index), to guide action towards the 2020 target. We found that>50% of the global deterioration in the conservation status of birds, mammals and amphibians is concentrated in <1% of the surface area, 39/1098 ecoregions (4%) and eight/195 countries (4%) – Australia, China, Colombia, Ecuador, Indonesia, Malaysia, Mexico, and the United States. These countries hold a third of global diversity in these vertebrate groups, partially explaining why they concentrate most of the losses. Yet, other megadiverse countries – most notably Brazil (responsible for 10% of species but just 1% of deterioration), plus India and Madagascar – performed better in conserving their share of global vertebrate diversity. Very few countries, mostly island nations (e.g. Cook Islands, Fiji, Mauritius, Seychelles, and Tonga), have achieved net improvements. Per capita wealth does not explain these patterns, with two of the richest countries – United States and Australia – fairing conspicuously poorly. Different countries were affected by different combinations of threats. Reducing global rates of biodiversity loss will require investment in the regions and countries with the highest responsibility for the world's biodiversity, focusing on conserving those species and areas most in peril and on reducing the drivers with the highest impacts. PMID:25426636

  12. Spatially explicit trends in the global conservation status of vertebrates.

    PubMed

    Rodrigues, Ana S L; Brooks, Thomas M; Butchart, Stuart H M; Chanson, Janice; Cox, Neil; Hoffmann, Michael; Stuart, Simon N

    2014-01-01

    The world's governments have committed to preventing the extinction of threatened species and improving their conservation status by 2020. However, biodiversity is not evenly distributed across space, and neither are the drivers of its decline, and so different regions face very different challenges. Here, we quantify the contribution of regions and countries towards recent global trends in vertebrate conservation status (as measured by the Red List Index), to guide action towards the 2020 target. We found that>50% of the global deterioration in the conservation status of birds, mammals and amphibians is concentrated in <1% of the surface area, 39/1098 ecoregions (4%) and eight/195 countries (4%) - Australia, China, Colombia, Ecuador, Indonesia, Malaysia, Mexico, and the United States. These countries hold a third of global diversity in these vertebrate groups, partially explaining why they concentrate most of the losses. Yet, other megadiverse countries - most notably Brazil (responsible for 10% of species but just 1% of deterioration), plus India and Madagascar - performed better in conserving their share of global vertebrate diversity. Very few countries, mostly island nations (e.g. Cook Islands, Fiji, Mauritius, Seychelles, and Tonga), have achieved net improvements. Per capita wealth does not explain these patterns, with two of the richest countries - United States and Australia - fairing conspicuously poorly. Different countries were affected by different combinations of threats. Reducing global rates of biodiversity loss will require investment in the regions and countries with the highest responsibility for the world's biodiversity, focusing on conserving those species and areas most in peril and on reducing the drivers with the highest impacts.

  13. Identification of prevalent vertebral fractures using CT lateral scout views: a comparison of semi-automated quantitative vertebral morphometry and radiologist semi-quantitative grading

    PubMed Central

    Kim, Y. M.; Demissie, S.; Genant, H. K.; Cheng, X.; Yu, W.; Samelson, E. J.; Kiel, D. P.

    2013-01-01

    Summary We compared vertebral fracture assessment by semi-automated quantitative vertebral morphometry measurements with the conventional semi-quantitative (SQ) grading using lateral CT scout views. The semi-automated morphometry method showed good to excellent agreement with the visual SQ grading by radiologists for identification of vertebral fractures. Introduction Semi-automated quantitative vertebral morphometry (QM) measurements may enhance management of osteoporosis patients by providing an efficient means to identify vertebral fractures (VFx). We compared identification of prevalent VFx by semi-automated QM to SQ grading. Methods A non-radiologist performed semi-automated QM from CT lateral scout views in 200 subjects (102 men, 98 women, 65.8±8.9 years) selected from the Framingham Heart Study Multidetector CT Study. VFx were classified in the QM approach based on using Genant’s criteria for deformities, and compared with conventional SQ grading performed by experienced radiologists as the gold standard. The kappa (k) statistics, percent agreement (% Agree), sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) were computed. Results Among 200 subjects, 57 had mild and 41 had moderate or severe VFx by visual SQ grading. Per-person analyses showed excellent agreement between the two methods, with k=0.780. The % Agree ranged from 86.7% to 91.2%, the SE was 81.3%–96%, and the SP was 86.5%–92%. Among 2,588 vertebrae analyzed, 107 had mild and 49 had moderate or severe VFx by visual SQ grading. Per-vertebra analyses revealed good agreement, with k=0.580. Agreement between the methods tended to be highest in L1-L4 region. Agreement and validity measures were higher when only moderate and severe fractures were included. Conclusion The semi-automated quantitative vertebral morphometry measurements from CT lateral scout views provided good to excellent agreement with the standard SQ grading for assessment of

  14. Vertebral artery dissecting aneurysm treated by internal trapping via the contralateral vertebral artery: A case report

    PubMed Central

    2015-01-01

    A 42-year-old man with a history of sudden onset of severe headache followed by consciousness disturbance was brought to our hospital. Radiological examinations revealed subarachnoid hemorrhage, associated with rupture of a left vertebral artery dissecting aneurysm. Initially, internal trapping was attempted via the ipsilateral vertebral artery. However, the microcatheter could not be navigated through the true lumen to the distal side of the vertebral artery. Subsequently, therefore, the guiding catheter was placed in the right vertebral artery, and the microcatheter was retrogradely navigated successfully through the lesion to the proximal side of the left vertebral artery. Finally, the lesion was completely embolized with electrodetachable coils without complications. However, the patient died after the operation because of deterioration of the general condition. The postmortem examination revealed how an intimal flap had interfered with the antegrade navigation of the microcatheter in the lesion. The present case showed that endovascular treatment for a vertebral artery dissecting aneurysm via the contralateral vertebral artery may be a useful option in cases where antegrade navigation of the microcatheter via the ipsilateral vertebral artery is found to be difficult. PMID:26116649

  15. Vertebral artery dissecting aneurysm treated by internal trapping via the contralateral vertebral artery: A case report.

    PubMed

    Kojima, Atsuhiro

    2015-10-01

    A 42-year-old man with a history of sudden onset of severe headache followed by consciousness disturbance was brought to our hospital. Radiological examinations revealed subarachnoid hemorrhage, associated with rupture of a left vertebral artery dissecting aneurysm. Initially, internal trapping was attempted via the ipsilateral vertebral artery. However, the microcatheter could not be navigated through the true lumen to the distal side of the vertebral artery. Subsequently, therefore, the guiding catheter was placed in the right vertebral artery, and the microcatheter was retrogradely navigated successfully through the lesion to the proximal side of the left vertebral artery. Finally, the lesion was completely embolized with electrodetachable coils without complications. However, the patient died after the operation because of deterioration of the general condition. The postmortem examination revealed how an intimal flap had interfered with the antegrade navigation of the microcatheter in the lesion. The present case showed that endovascular treatment for a vertebral artery dissecting aneurysm via the contralateral vertebral artery may be a useful option in cases where antegrade navigation of the microcatheter via the ipsilateral vertebral artery is found to be difficult.

  16. Spinal dermoid sinus in a Dachshund with vertebral and thoracic limb malformations

    PubMed Central

    2014-01-01

    Background Dermoid sinus is an uncommon epithelial-lined fistula that may be associated with vertebral malformations. In humans, Klippel-Feil syndrome (KFS) is a rare condition characterized by congenital cervical vertebral fusion and may be associated with other developmental defects, including dermoid sinus. The present case report describes an adult Dachshund with cervical and cranial thoracic vertebral malformations as well as thoracic limb malformations resembling KFS with a concurrent type IV dermoid sinus. Case presentation A 1.5 year-old Dachshund with congenital thoracic limbs deformities and cervical-thoracic vertebral malformations presented with cervical hyperesthesia, rigidity of the cervical musculature and tetraparesis. Neurologic, radiographic, and computed tomography (CT) (2D, 3D, CT fistulography) examinations revealed skeletal anomalies, a dermoid sinus in the cranial thoracic region and epidural gas within the vertebral canal. Surgical resection and histopathological evaluation of the sinus tract were performed and confirmed a type IV dermoid sinus. The clinical signs progressively recovered postoperatively, and no recurrent signs were observed after 6 months of follow-up. Conclusions Cervical vertebral malformations associated with limbs anomalies have not been reported in dogs and may represent a condition similar to KFS in humans. KFS can occur concurrently with other congenital conditions including dermoid sinus and should be included among the complex congenital anomalies described in dogs. PMID:24593884

  17. Conserved or lost: molecular evolution of the key gene GULO in vertebrate vitamin C biosynthesis.

    PubMed

    Yang, Hongwen

    2013-06-01

    L-gulono-gamma-lactone oxidase (GULO) catalyzes the final step in vertebrate vitamin C biosynthesis. Vitamin C-incapable vertebrates lack the GULO gene. Gene structure and phylogenetic analyses showed that vertebrate GULO genes are 64-95% identical at the amino acid level and consist of 11 conserved exons. GULO pseudogenes have multiple indel mutations and premature stop codons in higher primates, guinea pigs, and some bats. No GULO-like sequences were identified in teleost fishes. During animal GULO evolution, exon F was subdivided into F1 and F2. Additional GULO retropseudogenes were identified in dogs, cats, and giant pandas. GULO-flanking genome regions acquired frequent segment translocations and inversions during vertebrate evolution. Purifying selection was detected across vertebrate GULO genes (d(N)/d(S) = 0.069), except for some positively selected sites identified in sharks and frogs. These positive sites demonstrated little functional significance when mapped onto the three-dimensional GULO protein structure. Vertebrate GULO genes are conserved except for those that are lost.

  18. Comparative Studies of Vertebrate Lipoprotein Lipase: A Key Enzyme of Very Low Density Lipoprotein Metabolism

    PubMed Central

    Holmes, Roger S; Vandeberg, John L; Cox, Laura A

    2011-01-01

    Lipoprotein lipase (LIPL or LPL; E.C.3.1.1.34) serves a dual function as a triglyceride lipase of circulating chylomicrons and very-low-density lipoproteins (VLDL) and facilitates receptor-mediated lipoprotein uptake into heart, muscle and adipose tissue. Comparative LPL amino acid sequences and protein structures and LPL gene locations were examined using data from several vertebrate genome projects. Mammalian LPL genes usually contained 9 coding exons on the positive strand. Vertebrate LPL sequences shared 58–99% identity as compared with 33–49% sequence identities with other vascular triglyceride lipases, hepatic lipase (HL) and endothelial lipase (EL). Two human LPL N-glycosylation sites were conserved among seven predicted sites for the vertebrate LPL sequences examined. Sequence alignments, key amino acid residues and conserved predicted secondary and tertiary structures were also studied. A CpG island was identified within the 5'-untranslated region of the human LPL gene which may contribute to the higher than average (x4.5 times) level of expression reported. Phylogenetic analyses examined the relationships and potential evolutionary origins of vertebrate lipase genes, LPL, LIPG (encoding EL) and LIPC (encoding HL) which suggested that these have been derived from gene duplication events of an ancestral neutral lipase gene, prior to the appearance of fish during vertebrate evolution. Comparative divergence rates for these vertebrate sequences indicated that LPL is evolving more slowly (2–3 times) than for LIPC and LIPG genes and proteins. PMID:21561822

  19. Traumatic vertebral artery injury: detailed clinicopathologic and morphometric analysis of 6 cases.

    PubMed

    Lee, Carol K; Gray, Laurel; Maguire, John

    2009-06-01

    Traumatic vertebral artery injury is frequently fatal from what may often be mild trauma to the head and neck. Detailed examination of vertebral arteries is not frequently undertaken at autopsy: the structural and histologic changes that may be relevant to the development of the injury are not well known. We sampled vertebral arteries bilaterally from 6 forensic autopsies (age = 26-50 years; 3 of 6 suffered from alcohol toxicity) with documented intradural vertebral artery injuries, and 4 nonvertebral-artery-injury-related autopsies (age = 19-70 years). Intradural, dural, and extradural components from each artery were submitted for paraffin-embedded tissue processing. Multiple serial sections and special stains (hematoxylin and eosin, alcian blue pH 2.5, reticulin, Congo red) were independently examined by 2 pathologists. All 6 of 6 injured samples and 4 of 4 control samples showed degenerative changes (intimal fibrosis, focal disruption of the internal elastic lamina, and medial calcification). However, microscopic adventitial hemorrhages were only observed around peripheral nerves adjacent to the injured samples. These may be due to tracking of blood along perineural loose connective tissue regions of reduced resistance, and may be a useful finding that points to underlying vertebral artery injury. Thus, careful dissection and gross and microscopic, examination of the vertebral arteries, with particular attention to the intracranial segments, is recommended in all cases of fatal traumatic head and neck injuries.

  20. Evolution of innate and adaptive immune systems in jawless vertebrates.

    PubMed

    Kasamatsu, Jun

    2013-01-01

    Because jawless vertebrates are the most primitive vertebrates, they have been studied to gain understanding of the evolutionary processes that gave rise to the innate and adaptive immune systems in vertebrates. Jawless vertebrates have developed lymphocyte-like cells that morphologically resemble the T and B cells of jawed vertebrates, but they express variable lymphocyte receptors (VLRs) instead of the T and B cell receptors that specifically recognize antigens in jawed vertebrates. These VLRs act as antigen receptors, diversity being generated in their antigen-binding sites by assembly of highly diverse leucine-rich repeat modules. Therefore, jawless vertebrates have developed adaptive immune systems based on the VLRs. Although pattern recognition receptors, including Toll-like receptors (TLRs) and Rig-like receptors (RLRs), and their adaptor genes are conserved in jawless vertebrates, some transcription factor and inflammatory cytokine genes in the TLR and RLR pathways are not present. However, like jawed vertebrates, the initiation of adaptive immune responses in jawless vertebrates appears to require prior activation of the innate immune system. These observations imply that the innate immune systems of jawless vertebrates have a unique molecular basis that is distinct from that of jawed vertebrates. Altogether, although the molecular details of the innate and adaptive immune systems differ between jawless and jawed vertebrates, jawless vertebrates have developed versions of these immune systems that are similar to those of jawed vertebrates. © 2012 The Societies and Wiley Publishing Asia Pty Ltd.

  1. The fragmentation of Pangaea and Mesozoic terrestrial vertebrate biodiversity.

    PubMed

    Vavrek, Matthew J

    2016-09-01

    During the Mesozoic (242-66 million years ago), terrestrial regions underwent a massive shift in their size, position and connectivity. At the beginning of the era, the land masses were joined into a single supercontinent called Pangaea. However, by the end of the Mesozoic, terrestrial regions had become highly fragmented, both owing to the drifting apart of the continental plates and the extremely high sea levels that flooded and divided many regions. How terrestrial biodiversity was affected by this fragmentation and large-scale flooding of the Earth's landmasses is uncertain. Based on a model using the species-area relationship (SAR), terrestrial vertebrate biodiversity would be expected to nearly double through the Mesozoic owing to continental fragmentation, despite a decrease of 24% in total terrestrial area. Previous studies of Mesozoic vertebrates have generally found increases in terrestrial diversity towards the end of the era, although these increases are often attributed to intrinsic or climatic factors. Instead, continental fragmentation over this time may largely explain any observed increase in terrestrial biodiversity. This study demonstrates the importance that non-intrinsic effects can have on the taxonomic success of a group, and the importance of geography to understanding past biodiversity. © 2016 The Author(s).

  2. Enhancer turnover and conserved regulatory function in vertebrate evolution

    PubMed Central

    Domené, Sabina; Bumaschny, Viviana F.; de Souza, Flávio S. J.; Franchini, Lucía F.; Nasif, Sofía; Low, Malcolm J.; Rubinstein, Marcelo

    2013-01-01

    Mutations in regulatory regions including enhancers are an important source of variation and innovation during evolution. Enhancers can evolve by changes in the sequence, arrangement and repertoire of transcription factor binding sites, but whole enhancers can also be lost or gained in certain lineages in a process of turnover. The proopiomelanocortin gene (Pomc), which encodes a prohormone, is expressed in the pituitary and hypothalamus of all jawed vertebrates. We have previously described that hypothalamic Pomc expression in mammals is controlled by two enhancers—nPE1 and nPE2—that are derived from transposable elements and that presumably replaced the ancestral neuronal Pomc regulatory regions. Here, we show that nPE1 and nPE2, even though they are mammalian novelties with no homologous counterpart in other vertebrates, nevertheless can drive gene expression specifically to POMC neurons in the hypothalamus of larval and adult transgenic zebrafish. This indicates that when neuronal Pomc enhancers originated de novo during early mammalian evolution, the newly created cis- and trans-codes were similar to the ancestral ones. We also identify the neuronal regulatory region of zebrafish pomca and confirm that it is not homologous to the mammalian enhancers. Our work sheds light on the process of gene regulatory evolution by showing how a locus can undergo enhancer turnover and nevertheless maintain the ancestral transcriptional output. PMID:24218639

  3. The fragmentation of Pangaea and Mesozoic terrestrial vertebrate biodiversity

    PubMed Central

    2016-01-01

    During the Mesozoic (242–66 million years ago), terrestrial regions underwent a massive shift in their size, position and connectivity. At the beginning of the era, the land masses were joined into a single supercontinent called Pangaea. However, by the end of the Mesozoic, terrestrial regions had become highly fragmented, both owing to the drifting apart of the continental plates and the extremely high sea levels that flooded and divided many regions. How terrestrial biodiversity was affected by this fragmentation and large-scale flooding of the Earth's landmasses is uncertain. Based on a model using the species–area relationship (SAR), terrestrial vertebrate biodiversity would be expected to nearly double through the Mesozoic owing to continental fragmentation, despite a decrease of 24% in total terrestrial area. Previous studies of Mesozoic vertebrates have generally found increases in terrestrial diversity towards the end of the era, although these increases are often attributed to intrinsic or climatic factors. Instead, continental fragmentation over this time may largely explain any observed increase in terrestrial biodiversity. This study demonstrates the importance that non-intrinsic effects can have on the taxonomic success of a group, and the importance of geography to understanding past biodiversity. PMID:27651536

  4. A new mechanistic scenario for the origin and evolution of vertebrate cartilage.

    PubMed

    Cattell, Maria; Lai, Su; Cerny, Robert; Medeiros, Daniel Meulemans

    2011-01-01

    The appearance of cellular cartilage was a defining event in vertebrate evolution because it made possible the physical expansion of the vertebrate "new head". Despite its central role in vertebrate evolution, the origin of cellular cartilage has been difficult to understand. This is largely due to a lack of informative evolutionary intermediates linking vertebrate cellular cartilage to the acellular cartilage of invertebrate chordates. The basal jawless vertebrate, lamprey, has long been considered key to understanding the evolution of vertebrate cartilage. However, histological analyses of the lamprey head skeleton suggest it is composed of modern cellular cartilage and a putatively unrelated connective tissue called mucocartilage, with no obvious transitional tissue. Here we take a molecular approach to better understand the evolutionary relationships between lamprey cellular cartilage, gnathostome cellular cartilage, and lamprey mucocartilage. We find that despite overt histological similarity, lamprey and gnathostome cellular cartilage utilize divergent gene regulatory networks (GRNs). While the gnathostome cellular cartilage GRN broadly incorporates Runx, Barx, and Alx transcription factors, lamprey cellular cartilage does not express Runx or Barx, and only deploys Alx genes in certain regions. Furthermore, we find that lamprey mucocartilage, despite its distinctive mesenchymal morphology, deploys every component of the gnathostome cartilage GRN, albeit in different domains. Based on these findings, and previous work, we propose a stepwise model for the evolution of vertebrate cellular cartilage in which the appearance of a generic neural crest-derived skeletal tissue was followed by a phase of skeletal tissue diversification in early agnathans. In the gnathostome lineage, a single type of rigid cellular cartilage became dominant, replacing other skeletal tissues and evolving via gene cooption to become the definitive cellular cartilage of modern jawed

  5. A New Mechanistic Scenario for the Origin and Evolution of Vertebrate Cartilage

    PubMed Central

    Cattell, Maria; Lai, Su; Cerny, Robert; Medeiros, Daniel Meulemans

    2011-01-01

    The appearance of cellular cartilage was a defining event in vertebrate evolution because it made possible the physical expansion of the vertebrate “new head”. Despite its central role in vertebrate evolution, the origin of cellular cartilage has been difficult to understand. This is largely due to a lack of informative evolutionary intermediates linking vertebrate cellular cartilage to the acellular cartilage of invertebrate chordates. The basal jawless vertebrate, lamprey, has long been considered key to understanding the evolution of vertebrate cartilage. However, histological analyses of the lamprey head skeleton suggest it is composed of modern cellular cartilage and a putatively unrelated connective tissue called mucocartilage, with no obvious transitional tissue. Here we take a molecular approach to better understand the evolutionary relationships between lamprey cellular cartilage, gnathostome cellular cartilage, and lamprey mucocartilage. We find that despite overt histological similarity, lamprey and gnathostome cellular cartilage utilize divergent gene regulatory networks (GRNs). While the gnathostome cellular cartilage GRN broadly incorporates Runx, Barx, and Alx transcription factors, lamprey cellular cartilage does not express Runx or Barx, and only deploys Alx genes in certain regions. Furthermore, we find that lamprey mucocartilage, despite its distinctive mesenchymal morphology, deploys every component of the gnathostome cartilage GRN, albeit in different domains. Based on these findings, and previous work, we propose a stepwise model for the evolution of vertebrate cellular cartilage in which the appearance of a generic neural crest-derived skeletal tissue was followed by a phase of skeletal tissue diversification in early agnathans. In the gnathostome lineage, a single type of rigid cellular cartilage became dominant, replacing other skeletal tissues and evolving via gene cooption to become the definitive cellular cartilage of modern jawed

  6. Anatomy and biomechanics of the vertebral aponeurosis part of the posterior layer of the thoracolumbar fascia.

    PubMed

    Loukas, Marios; Shoja, Mohammadali M; Thurston, Todd; Jones, Virginia L; Linganna, Sanjay; Tubbs, R Shane

    2008-03-01

    There is significant paucity in the literature regarding vertebral aponeurosis. We were able to find only a few descriptions of this specific fascia in the extant medical literature. To elucidate further the anatomy of this structure, forty adult human cadavers were dissected. Both quantitation and anatomical observations were made of the vertebral aponeurosis. The vertebral aponeurosis was identified in 100% of specimens. This fascia was identified as a thin fibrous layer consisting of longitudinal and transverse connective tissue fibers blended together deep to the latissimus dorsi muscle. It attached medially to the spinous processes of the of the thoracic vertebrae; laterally to the angles of ribs; inferiorly to the fascia covering the serratus posterior inferior muscle (superficial lamina of the posterior layer of thoracolumbar fascia); superiorly it ran deep to the serratus posterior superior and splenius capitis muscles to blend with the deep fascia of the neck. At the level of the serratus posterior inferior muscle, the vertebral aponeurosis fused to form a continuous layer descending toward the sacrotuberous ligament covering the erector spinae muscle. Morphometrically, the mean length of the vertebral aponeurosis was 38 cm and the mean width was 24 cm. The mean thickness was three mm. There was no significant difference between left and right sides, gender or age with regard to vertebral aponeurosis length, width, or thickness (P > 0.05). During manual tension of the vertebral aponeurosis, the tensile force necessary for failure had a mean of 38.7 N. In all specimens, the vertebral aponeurosis was capable of holding sutures placed through its substance. We hope that these data will be of use for descriptive purposes and may potentially add to our understanding of the biomechanics involved in movements of the back. As back pain is perhaps the most common reason patients visit their physicians, additional knowledge of this anatomical region is important.

  7. Vertebral Development in Paleozoic and Mesozoic Tetrapods Revealed by Paleohistological Data

    PubMed Central

    Danto, Marylène; Witzmann, Florian; Fröbisch, Nadia B.

    2016-01-01

    Basal tetrapods display a wide spectrum of vertebral centrum morphologies that can be used to distinguish different tetrapod groups. The vertebral types range from multipartite centra in stem-tetrapods, temnospondyls, and seymouriamorphs up to monospondylous centra in lepospondyls and have been drawn upon for reconstructing major evolutionary trends in tetrapods that are now considered textbook knowledge. Two modes of vertebral formation have been postulated: the multipartite vertebrae formed first as cartilaginous elements with subsequent ossification. The monospondylous centrum, in contrast, was formed by direct ossification without a cartilaginous precursor. This study describes centrum morphogenesis in basal tetrapods for the first time, based on bone histology. Our results show that the intercentra of the investigated stem-tetrapods consist of a small band of periosteal bone and a dense network of endochondral bone. In stereospondyl temnospondyls, high amounts of calcified cartilage are preserved in the endochondral trabeculae. Notably, the periosteal region is thickened and highly vascularized in the plagiosaurid stereospondyls. Among “microsaur” lepospondyls, the thickened periosteal region is composed of compact bone and the notochordal canal is surrounded by large cell lacunae. In nectridean lepospondyls, the periosteal region has a spongy structure with large intertrabecular spaces, whereas the endochondral region has a highly cancellous structure. Our observations indicate that regardless of whether multipartite or monospondylous, the centra of basal tetrapods display first endochondral and subsequently periosteal ossification. A high interspecific variability is observed in growth rate, organization, and initiation of periosteal ossification. Moreover, vertebral development and structure reflect different lifestyles. The bottom-dwelling Plagiosauridae increase their skeletal mass by hyperplasy of the periosteal region. In nectrideans, the skeletal

  8. Computer-assisted analysis of cervical vertebral bone age using cephalometric radiographs in Brazilian subjects.

    PubMed

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

    2010-01-01

    The aims of this study were to develop a computerized program for objectively evaluating skeletal maturation on cephalometric radiographs, and to apply the new method to Brazilian subjects. The samples were taken from the patient files of Oral Radiological Clinics from the North, Northeast, Midwest and South regions of the country. A total of 717 subjects aged 7.0 to 15.9 years who had lateral cephalometric radiographs and hand-wrist radiographs were selected. A cervical vertebral computerized analysis was created in the Radiocef Studio 2 computer software for digital cephalometric analysis, and cervical vertebral bone age was calculated using the formulas developed by Caldas et al.17 (2007). Hand-wrist bone age was evaluated by the TW3 method. Analysis of variance (ANOVA) and the Tukey test were used to compare cervical vertebral bone age, hand-wrist bone age and chronological age (P < 0.05). No significant difference was found between cervical vertebral bone age and chronological age in all regions studied. When analyzing bone age, it was possible to observe a statistically significant difference between cervical vertebral bone age and hand-wrist bone age for female and male subjects in the North and Northeast regions, as well as for male subjects in the Midwest region. No significant difference was observed between bone age and chronological age in all regions except for male subjects in the North and female subjects in the Northeast. Using cervical vertebral bone age, it might be possible to evaluate skeletal maturation in an objective manner using cephalometric radiographs.

  9. Vertebral Development in Paleozoic and Mesozoic Tetrapods Revealed by Paleohistological Data.

    PubMed

    Danto, Marylène; Witzmann, Florian; Fröbisch, Nadia B

    2016-01-01

    Basal tetrapods display a wide spectrum of vertebral centrum morphologies that can be used to distinguish different tetrapod groups. The vertebral types range from multipartite centra in stem-tetrapods, temnospondyls, and seymouriamorphs up to monospondylous centra in lepospondyls and have been drawn upon for reconstructing major evolutionary trends in tetrapods that are now considered textbook knowledge. Two modes of vertebral formation have been postulated: the multipartite vertebrae formed first as cartilaginous elements with subsequent ossification. The monospondylous centrum, in contrast, was formed by direct ossification without a cartilaginous precursor. This study describes centrum morphogenesis in basal tetrapods for the first time, based on bone histology. Our results show that the intercentra of the investigated stem-tetrapods consist of a small band of periosteal bone and a dense network of endochondral bone. In stereospondyl temnospondyls, high amounts of calcified cartilage are preserved in the endochondral trabeculae. Notably, the periosteal region is thickened and highly vascularized in the plagiosaurid stereospondyls. Among "microsaur" lepospondyls, the thickened periosteal region is composed of compact bone and the notochordal canal is surrounded by large cell lacunae. In nectridean lepospondyls, the periosteal region has a spongy structure with large intertrabecular spaces, whereas the endochondral region has a highly cancellous structure. Our observations indicate that regardless of whether multipartite or monospondylous, the centra of basal tetrapods display first endochondral and subsequently periosteal ossification. A high interspecific variability is observed in growth rate, organization, and initiation of periosteal ossification. Moreover, vertebral development and structure reflect different lifestyles. The bottom-dwelling Plagiosauridae increase their skeletal mass by hyperplasy of the periosteal region. In nectrideans, the skeletal mass

  10. Vertebral Column Resection for Rigid Spinal Deformity

    PubMed Central

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

    2017-01-01

    Study Design: Broad narrative review. Objective: To review the evolution, operative technique, outcomes, and complications associated with posterior vertebral column resection. Methods: 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. Results: 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. Conclusion: 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. PMID:28660112

  11. Vertebrate extracellular preovulatory and postovulatory egg coats.

    PubMed

    Menkhorst, Ellen; Selwood, Lynne

    2008-11-01

    Extracellular egg coats deposited by maternal or embryonic tissues surround all vertebrate conceptuses during early development. In oviparous species, the time of hatching from extracellular coats can be considered equivalent to the time of birth in viviparous species. Extracellular coats must be lost during gestation for implantation and placentation to occur in some viviparous species. In the most recent classification of vertebrate extracellular coats, Boyd and Hamilton (Cleavage, early development and implantation of the egg. In: Parkes AS (ed.), Marshall's Physiology of Reproduction, vol. 2, 3rd ed. London: Longmans, Green & Co; 1961:1-126) defined the coat synthesized by the oocyte during oogenesis as primary and the coat deposited by follicle cells surrounding the oocyte as secondary. Tertiary egg coats are those synthesized and deposited around the primary or secondary coat by the maternal reproductive tract. This classification is difficult to reconcile with recent data collected using modern molecular biological techniques that can accurately establish the site of coat precursor synthesis and secretion. We propose that a modification to the classification by Boyd and Hamilton is required. Vertebrate egg coats should be classed as belonging to the following two broad groups: the preovulatory coat, which is deposited during oogenesis by the oocyte or follicle cells, and the postovulatory coats, which are deposited after fertilization by the reproductive tract or conceptus. This review discusses the origin and classification of vertebrate extracellular preovulatory and postovulatory coats and illustrates what is known about coat homology between the vertebrate groups.

  12. Vertebral Column Resection for Rigid Spinal Deformity.

    PubMed

    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.

  13. The origin of the vertebrate skeleton

    NASA Astrophysics Data System (ADS)

    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.

  14. Cervical Vertebral Body Chordoma in a Cat.

    PubMed

    Hampel, R; Taylor-Brown, F; Priestnall, S L

    2016-05-01

    A 9-year-old, neutered female Maine Coon cat with a 6-week history of progressive ataxia was diagnosed with a cervical vertebral body mass using magnetic resonance imaging. The mass displaced and compressed the cervical spinal cord. The cat was humanely destroyed and necropsy examination confirmed a mass within the second cervical vertebral body. Microscopically, the mass was composed of large, clear, vacuolated ('physaliferous') cells. Immunohistochemically, the neoplastic cells expressed both cytokeratin and vimentin and the final diagnosis was a cervical, vertebral body chordoma. This is only the third report of a chordoma in this species and the first in this location. Chordoma should be considered as a potential differential diagnosis for tumours arising from the cervical vertebrae in the cat.

  15. Chitin is endogenously produced in vertebrates.

    PubMed

    Tang, W Joyce; Fernandez, Javier; Sohn, Joel J; Amemiya, Chris T

    2015-03-30

    Chitin, a biopolymer of N-acetylglucosamine, is abundant in invertebrates and fungi and is an important structural molecule [1, 2]. There has been a longstanding belief that vertebrates do not produce chitin; however, we have obtained compelling evidence to the contrary. Chitin synthase genes are present in numerous fishes and amphibians, and chitin is localized in situ to the lumen of the developing zebrafish gut, in epithelial cells of fish scales, and in at least three different cell types in larval salamander appendages. Chitin synthase gene knockdowns and various histochemical experiments in zebrafish further authenticated our results. Finally, a polysaccharide was extracted from scales of salmon that exhibited all the chemical hallmarks of chitin. Our data and analyses demonstrate the existence of endogenous chitin in vertebrates and suggest that it serves multiple roles in vertebrate biology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Three Distinct Glutamate Decarboxylase Genes in Vertebrates

    PubMed Central

    Grone, Brian P.; Maruska, Karen P.

    2016-01-01

    Gamma-aminobutyric acid (GABA) is a widely conserved signaling molecule that in animals has been adapted as a neurotransmitter. GABA is synthesized from the amino acid glutamate by the action of glutamate decarboxylases (GADs). Two vertebrate genes, GAD1 and GAD2, encode distinct GAD proteins: GAD67 and GAD65, respectively. We have identified a third vertebrate GAD gene, GAD3. This gene is conserved in fishes as well as tetrapods. We analyzed protein sequence, gene structure, synteny, and phylogenetics to identify GAD3 as a homolog of GAD1 and GAD2. Interestingly, we found that GAD3 was lost in the hominid lineage. Because of the importance of GABA as a neurotransmitter, GAD3 may play important roles in vertebrate nervous systems. PMID:27461130

  17. Chitin is endogenously produced in vertebrates

    PubMed Central

    Sohn, Joel J.; Amemiya, Chris T.

    2015-01-01

    Chitin, a biopolymer of N-acetylglucosamine, is abundant in invertebrates and fungi, and is an important structural molecule. There has been a longstanding belief that vertebrates do not produce chitin, however, we have obtained compelling evidence to the contrary. Chitin synthase genes are present in numerous fishes and amphibians, and chitin is localized in situ to the lumen of the developing zebrafish gut, in epithelial cells of fish scales, and in at least three different cell types in larval salamander appendages. Chitin synthase gene knockdowns and various histochemical experiments in zebrafish further authenticated our results. Finally, a polysaccharide was extracted from scales of salmon that exhibited all the chemical hallmarks of chitin. Our data and analyses demonstrate the existence of endogenous chitin in vertebrates and suggest that it serves multiple roles in vertebrate biology. PMID:25772447

  18. The evolution of early vertebrate photoreceptors

    PubMed Central

    Collin, Shaun P.; Davies, Wayne L.; Hart, Nathan S.; Hunt, David M.

    2009-01-01

    Meeting the challenge of sampling an ancient aquatic landscape by the early vertebrates was crucial to their survival and would establish a retinal bauplan to be used by all subsequent vertebrate descendents. Image-forming eyes were under tremendous selection pressure and the ability to identify suitable prey and detect potential predators was thought to be one of the major drivers of speciation in the Early Cambrian. Based on the fossil record, we know that hagfishes, lampreys, holocephalans, elasmobranchs and lungfishes occupy critical stages in vertebrate evolution, having remained relatively unchanged over hundreds of millions of years. Now using extant representatives of these ‘living fossils’, we are able to piece together the evolution of vertebrate photoreception. While photoreception in hagfishes appears to be based on light detection and controlling circadian rhythms, rather than image formation, the photoreceptors of lampreys fall into five distinct classes and represent a critical stage in the dichotomy of rods and cones. At least four types of retinal cones sample the visual environment in lampreys mediating photopic (and potentially colour) vision, a sampling strategy retained by lungfishes, some modern teleosts, reptiles and birds. Trichromacy is retained in cartilaginous fishes (at least in batoids and holocephalans), where it is predicted that true scotopic (dim light) vision evolved in the common ancestor of all living gnathostomes. The capacity to discriminate colour and balance the tradeoff between resolution and sensitivity in the early vertebrates was an important driver of eye evolution, where many of the ocular features evolved were retained as vertebrates progressed on to land. PMID:19720654

  19. Renal-vertebral index in normal children.

    PubMed Central

    Bacopoulos, C; Papahatzi-Kalmadi, M; Karpathios, T; Thomaidis, T; Matsaniotis, N

    1981-01-01

    The renal-vertebral index is a simple method of evaluating the renal length in children and is convenient for everyday clinical work. The results of 822 normal children aged between 3 days and 14 years are reported. Infants of up to 1 year were found to have an index of about 4 to 5, pre-school children are an index of 3 1/2 to 4 1/2, and schoolchildren an index of 3 1/2 to 4. There was no significant difference in renal-vertebral index between boys and girls. Images Fig. 1 PMID:7259261

  20. Scenarios for the making of vertebrates.

    PubMed

    Holland, Nicholas D; Holland, Linda Z; Holland, Peter W H

    2015-04-23

    Over the past 200 years, almost every invertebrate phylum has been proposed as a starting point for evolving vertebrates. Most of these scenarios are outdated, but several are still seriously considered. The short-range transition from ancestral invertebrate chordates (similar to amphioxus and tunicates) to vertebrates is well accepted. However, longer-range transitions leading up to the invertebrate chordates themselves are more controversial. Opinion is divided between the annelid and the enteropneust scenarios, predicting, respectively, a complex or a simple ancestor for bilaterian animals. Deciding between these ideas will be facilitated by further comparative studies of multicellular animals, including enigmatic taxa such as xenacoelomorphs.

  1. Complex osteotomies vertebral column resection and decancellation.

    PubMed

    Obeid, Ibrahim; Bourghli, Anouar; Boissière, Louis; Vital, Jean-Marc; Barrey, Cédric

    2014-07-01

    Pedicle subtraction osteotomy (PSO) is nowadays widely used to treat sagittal imbalance. Some complex malalignment cases cannot be treated by a PSO, whereas the imbalance is coronal or mixed or the sagittal imbalance is major and cannot be treated by a single PSO. The aim of this article was to review these complex situations--coronal imbalance, mixed imbalance, two-level PSO, vertebral column resection, and vertebral column decancellation, and to focus on their specificities. It wills also to evoke the utility of navigation in these complex cases.

  2. Percutaneous vertebral augmentation for painful osteolytic vertebral metastasis: a case report

    PubMed Central

    Anselmetti, Giovanni C; Tutton, Sean M; Facchini, Francis R; Miller, Larry E; Block, Jon E

    2012-01-01

    Introduction Vertebral metastases are associated with significant pain, disability, and morbidity. Open surgery for fracture stabilization is often inappropriate in this population due to a poor risk-benefit profile, particularly if life expectancy is short. Percutaneous vertebroplasty and kyphoplasty are appealing adjunctive procedures in patients with malignancy for alleviation of intractable pain. However, these patients have higher risk of serious complications, notably cement extravasation. Described in this report is a case of a painful osteolytic vertebral metastasis that was successfully treated by a novel percutaneous vertebral augmentation system. Case presentation A 42-year-old Caucasian female presented with a history of metastatic lung cancer unresponsive to radiation and chemotherapy with symptoms inadequately controlled by opiates over the previous 6 months. Magnetic resonance imaging and spiral computed tomography with two-dimensional reconstruction showed an osteolytic vertebral metastasis with complete involvement of the T10 vertebral body, extending to the cortical vertebral wall anteriorly and posteriorly. The patient was treated with percutaneous vertebral augmentation (Kiva® VCF Treatment System, Benvenue Medical, Inc, Santa Clara, CA) utilizing a novel coil-shaped polyetheretherketone implant designed to minimize the risk of cement extravasation. After the minimally invasive procedure, bone cement distribution within the vertebral body was ideal, with no observed cement extravasation. No complications were reported, pain completely resolved within 24 hours, and use of intravenous narcotics was progressively diminished within 1 week. Complete pain relief was maintained throughout 4 months of follow-up. Conclusion The Kiva System represents a novel and effective minimally invasive treatment option for patients suffering from severe pain due to osteolytic vertebral metastasis. PMID:23754917

  3. Nematode sbRNAs: homologs of vertebrate Y RNAs.

    PubMed

    Boria, Ilenia; Gruber, Andreas R; Tanzer, Andrea; Bernhart, Stephan H; Lorenz, Ronny; Mueller, Michael M; Hofacker, Ivo L; Stadler, Peter F

    2010-04-01

    Stem-bulge RNAs (sbRNAs) are a group of small, functionally yet uncharacterized noncoding RNAs first described in C. elegans, with a few homologous sequences postulated in C. briggsae. In this study, we report on a comprehensive survey of this ncRNA family in the phylum Nematoda. Employing homology search strategies based on both sequence and secondary structure models and a computational promoter screen we identified a total of 240 new sbRNA homologs. For the majority of these loci we identified both promoter regions and transcription termination signals characteristic for pol-III transcripts. Sequence and structure comparison with known RNA families revealed that sbRNAs are homologs of vertebrate Y RNAs. Most of the sbRNAs show the characteristic Ro protein binding motif, and contain a region highly similar to a functionally required motif for DNA replication previously thought to be unique to vertebrate Y RNAs. The single Y RNA that was previously described in C. elegans, however, does not show this motif, and in general bears the hallmarks of a highly derived family member.

  4. Percutaneous ethanol embolization and cement augmentation of aggressive vertebral hemangiomas at two adjacent vertebral levels.

    PubMed

    Cianfoni, Alessandro; Massari, Francesco; Dani, Genta; Lena, Jonathan R; Rumboldt, Zoran; Vandergrift, William A; Bonaldi, Giuseppe

    2014-10-01

    This report describes a case of successful percutaneous direct-puncture ethanol embolization, followed by vertebroplasty, of an aggressive vertebral hemangioma (VH) involving two adjacent thoracic vertebral levels. In this case, the 78-year-old male patient presented with a 6-month history of progressive paraparesis due to spinal cord compression by a T8-T9 VH with an extensive epidural component. Follow-up demonstrated epidural component shrinkage with complete regression of symptoms at 3 months. This case suggests that exclusive percutaneous treatment may be considered for symptomatic VH even when two adjacent vertebral levels are affected.

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

    PubMed Central

    Liang, Cheng-Loong; Wang, Hao-Kwan; Syu, Fei-Kai; Wang, Kuo-Wei; Lu, Kang; Liliang, Po-Chou

    2015-01-01

    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 anti-inflammatory drugs (NSAIDs) (AOR=6.14; 95% CI: 5.08–7.41) were more likely to undergo repeat vertebral augmentation. Conclusion We conclude that the incidence of repeat vertebral augmentation is rather high. An understanding of risk factors predicting repeat

  6. Three neuropeptide Y receptor genes in the spiny dogfish, Squalus acanthias, support en bloc duplications in early vertebrate evolution.

    PubMed

    Salaneck, Erik; Ardell, David H; Larson, Earl T; Larhammar, Dan

    2003-08-01

    It has been debated whether the increase in gene number during early vertebrate evolution was due to multiple independent gene duplications or synchronous duplications of many genes. We describe here the cloning of three neuropeptide Y (NPY) receptor genes belonging to the Y1 subfamily in the spiny dogfish, Squalus acanthias, a cartilaginous fish. The three genes are orthologs of the mammalian subtypes Y1, Y4, and Y6, which are located in paralogous gene regions on different chromosomes in mammals. Thus, these genes arose by duplications of a chromosome region before the radiation of gnathostomes (jawed vertebrates). Estimates of duplication times from linearized trees together with evidence from other gene families supports two rounds of chromosome duplications or tetraploidizations early in vertebrate evolution. The anatomical distribution of mRNA was determined by reverse-transcriptase PCR and was found to differ from mammals, suggesting differential functional diversification of the new gene copies during the radiation of the vertebrate classes.

  7. Did Language Evolve Like the Vertebrate Eye?

    ERIC Educational Resources Information Center

    Botha, Rudolf P.

    2002-01-01

    Offers a critical appraisal of the way in which the idea that human language or some of its features evolved like the vertebrate eye by natural selection is articulated in Pinker and Bloom's (1990) selectionist account of language evolution. Argues that this account is less than insightful because it fails to draw some of the conceptual…

  8. Why can't vertebrates synthesize trehalose?

    PubMed

    Argüelles, Juan-Carlos

    2014-10-01

    The non-reducing disaccharide trehalose is a singular molecule, which has been strictly conserved throughout evolution in prokaryotes (bacteria and archaea), lower eukaryotes, plants, and invertebrates, but is absent in vertebrates and-more specifically-in mammals. There are notable differences regarding the pivotal roles played by trehalose among distantly related organisms as well as in the specific metabolic pathways of trehalose biosynthesis and/or hydrolysis, and the regulatory mechanisms that control trehalose expression genes and enzymatic activities. The success of trehalose compared with that of other structurally related molecules is attributed to its exclusive set of physical properties, which account for its physiological roles and have also promoted important biotechnological applications. However, an intriguing question still remains: why are vertebrates in general, and mammals in particular, unable (or have lost the capacity) to synthesize trehalose? The search for annotated genomes of vertebrates reveals the absence of any functional trehalose synthase gene. Indeed, this is also true for the human genome, which contains, however, two genes encoding for isoforms of the hydrolytic activity (trehalase). Although we still lack a convincing answer, this striking difference might reflect the divergent evolutionary lineages followed by invertebrates and vertebrates. Alternatively, some clinical data point to trehalose as a toxic molecule when stored inside the human body.

  9. Vertebrate Pest Control. Sale Publication 4077.

    ERIC Educational Resources Information Center

    Stimmann, M. W.; Clark, Dell O.

    This guide gives descriptions of common vertebrate pests and guidelines for using some common pesticides. The pests discussed are rats, mice, bats, moles, muskrats, ground squirrels, and gophers. Information is given for each pest on the type of damage the pest can do, the habitat and biology of the pest, and the most effective control methods.…

  10. Control of Vertebrate Pests of Agricultural Crops.

    ERIC Educational Resources Information Center

    Wingard, Robert G.; Studholme, Clinton R.

    This agriculture extension service publication of Pennsylvania State University discusses the damage from and control of vertebrate pests. Specific discussions describe the habits, habitat, and various control measures for blackbirds and crows, deer, meadow and pine mice, European starlings, and woodchucks. Where confusion with non-harmful species…

  11. Ancestral vertebrate complexity of the opioid system.

    PubMed

    Larhammar, Dan; Bergqvist, Christina; Sundström, Görel

    2015-01-01

    The evolution of the opioid peptides and nociceptin/orphanin as well as their receptors has been difficult to resolve due to variable evolutionary rates. By combining sequence comparisons with information on the chromosomal locations of the genes, we have deduced the following evolutionary scenario: The vertebrate predecessor had one opioid precursor gene and one receptor gene. The two genome doublings before the vertebrate radiation resulted in three peptide precursor genes whereupon a fourth copy arose by a local gene duplication. These four precursors diverged to become the prepropeptides for endorphin (POMC), enkephalins, dynorphins, and nociceptin, respectively. The ancestral receptor gene was quadrupled in the genome doublings leading to delta, kappa, and mu and the nociceptin/orphanin receptor. This scenario is corroborated by new data presented here for coelacanth and spotted gar, representing two basal branches in the vertebrate tree. A third genome doubling in the ancestor of teleost fishes generated additional gene copies. These results show that the opioid system was quite complex already in the first vertebrates and that it has more components in teleost fishes than in mammals. From an evolutionary point of view, nociceptin and its receptor can be considered full-fledged members of the opioid system.

  12. Late development of hagfish vertebral elements.

    PubMed

    Ota, Kinya G; Fujimoto, Satoko; Oisi, Yasuhiro; Kuratani, Shigeru

    2013-05-01

    It has been demonstrated recently that hagfishes, one of two groups of extant jawless vertebrates, have cartilaginous vertebral elements. Embryological and gene expression analyses have also shown that this group of animals develops a sclerotome, the potential primordium of the axial skeleton. However, it has not been shown unequivocally that the hagfish sclerotome truly differentiates into cartilage, because access to late-stage embryos and information about the cartilaginous extracellular matrix (ECM) are lacking for these animals. Here we investigated the expression patterns of the biglycan/decorin (BGN/DCN) gene in the inshore hagfish, Eptatretus burgeri. The homologue of this gene encodes the major noncollagenous component of the cartilaginous ECM among gnathostomes. We clearly identified the expression of this gene in adult vertebral tissues and in embryonic mesenchymal cells on the ventral aspect of the notochord. Taking into account that the sclerotome in the gnathostomes expresses BGN/DCN gene during the chondrogenesis, it is highly expected the hagfish BGN/DCN-positive mesenchymal cells are derived from the sclerotomes. We propose that hagfishes and gnathostomes share conserved developmental mechanisms not only in their somite differentiation, but also in chondrogenesis of their vertebral elements. Copyright © 2013 Wiley Periodicals, Inc.

  13. A Cambrian origin for vertebrate rods

    PubMed Central

    Asteriti, Sabrina; Grillner, Sten; Cangiano, Lorenzo

    2015-01-01

    Vertebrates acquired dim-light vision when an ancestral cone evolved into the rod photoreceptor at an unknown stage preceding the last common ancestor of extant jawed vertebrates (∼420 million years ago Ma). The jawless lampreys provide a unique opportunity to constrain the timing of this advance, as their line diverged ∼505 Ma and later displayed high-morphological stability. We recorded with patch electrodes the inner segment photovoltages and with suction electrodes the outer segment photocurrents of Lampetra fluviatilis retinal photoreceptors. Several key functional features of jawed vertebrate rods are present in their phylogenetically homologous photoreceptors in lamprey: crucially, the efficient amplification of the effect of single photons, measured by multiple parameters, and the flow of rod signals into cones. These results make convergent evolution in the jawless and jawed vertebrate lines unlikely and indicate an early origin of rods, implying strong selective pressure toward dim-light vision in Cambrian ecosystems. DOI: http://dx.doi.org/10.7554/eLife.07166.001 PMID:26095697

  14. Diagnosis and Management of Vertebral Compression Fractures.

    PubMed

    McCarthy, Jason; Davis, Amy

    2016-07-01

    Vertebral compression fractures (VCFs) are the most common complication of osteoporosis, affecting more than 700,000 Americans annually. Fracture risk increases with age, with four in 10 white women older than 50 years experiencing a hip, spine, or vertebral fracture in their lifetime. VCFs can lead to chronic pain, disfigurement, height loss, impaired activities of daily living, increased risk of pressure sores, pneumonia, and psychological distress. Patients with an acute VCF may report abrupt onset of back pain with position changes, coughing, sneezing, or lifting. Physical examination findings are often normal, but can demonstrate kyphosis and midline spine tenderness. More than two-thirds of patients are asymptomatic and diagnosed incidentally on plain radiography. Acute VCFs may be treated with analgesics such as acetaminophen, nonsteroidal anti-inflammatory drugs, narcotics, and calcitonin. Physicians must be mindful of medication adverse effects in older patients. Other conservative therapeutic options include limited bed rest, bracing, physical therapy, nerve root blocks, and epidural injections. Percutaneous vertebral augmentation, including vertebroplasty and kyphoplasty, is controversial, but can be considered in patients with inadequate pain relief with nonsurgical care or when persistent pain substantially affects quality of life. Family physicians can help prevent vertebral fractures through management of risk factors and the treatment of osteoporosis.

  15. Vertebrate Pest Control. Sale Publication 4077.

    ERIC Educational Resources Information Center

    Stimmann, M. W.; Clark, Dell O.

    This guide gives descriptions of common vertebrate pests and guidelines for using some common pesticides. The pests discussed are rats, mice, bats, moles, muskrats, ground squirrels, and gophers. Information is given for each pest on the type of damage the pest can do, the habitat and biology of the pest, and the most effective control methods.…

  16. Did Language Evolve Like the Vertebrate Eye?

    ERIC Educational Resources Information Center

    Botha, Rudolf P.

    2002-01-01

    Offers a critical appraisal of the way in which the idea that human language or some of its features evolved like the vertebrate eye by natural selection is articulated in Pinker and Bloom's (1990) selectionist account of language evolution. Argues that this account is less than insightful because it fails to draw some of the conceptual…

  17. Late Development of Hagfish Vertebral Elements

    PubMed Central

    Ota, Kinya G; Fujimoto, Satoko; Oisi, Yasuhiro; Kuratani, Shigeru

    2013-01-01

    It has been demonstrated recently that hagfishes, one of two groups of extant jawless vertebrates, have cartilaginous vertebral elements. Embryological and gene expression analyses have also shown that this group of animals develops a sclerotome, the potential primordium of the axial skeleton. However, it has not been shown unequivocally that the hagfish sclerotome truly differentiates into cartilage, because access to late-stage embryos and information about the cartilaginous extracellular matrix (ECM) are lacking for these animals. Here we investigated the expression patterns of the biglycan/decorin (BGN/DCN) gene in the inshore hagfish, Eptatretus burgeri. The homologue of this gene encodes the major noncollagenous component of the cartilaginous ECM among gnathostomes. We clearly identified the expression of this gene in adult vertebral tissues and in embryonic mesenchymal cells on the ventral aspect of the notochord. Taking into account that the sclerotome in the gnathostomes expresses BGN/DCN gene during the chondrogenesis, it is highly expected the hagfish BGN/DCN-positive mesenchymal cells are derived from the sclerotomes. We propose that hagfishes and gnathostomes share conserved developmental mechanisms not only in their somite differentiation, but also in chondrogenesis of their vertebral elements. J. Exp. Zool. (Mol. Dev. Evol.) 320B:129–139, 2013. © 2013 Wiley Periodicals, Inc. PMID:23401412

  18. Mast cells in nonmammalian vertebrates: an overview.

    PubMed

    Baccari, Gabriella Chieffi; Pinelli, Claudia; Santillo, Alessandra; Minucci, Sergio; Rastogi, Rakesh Kumar

    2011-01-01

    Mast cells are best known as multifunctional entities that may confer a benefit on immune system. This review presents the known facts on mast-cell system and breakthroughs in mast-cell biology in fish, amphibians, reptiles, and birds. As compared to mammals, there are relatively few data available on mast cells in many nonmammalian vertebrates. Nevertheless, like in mammals, mast cells in nonmammalian vertebrates contain a wide range of bioactive compounds including histamine, heparin, neuropeptides, and neutral proteases. In bony fishes, these cells secrete antimicrobial peptides as well. Mast cells have a widespread distribution in the brain, endocrine glands, intestine, liver, kidney, skin, tongue, and lungs, the highest concentration occurring in different tissues in the different taxa. Currently, researchers are grappling with the nature of scientific support to substantiate the functional importance of mast cells in nonmammalian vertebrates. Ultimately, the origin and evolution of vertebrate mast cell is of great interest to comparative immunologists seeking an underlying trend in the phylogenetic development of immunity.

  19. VerSeDa: vertebrate secretome database

    PubMed Central

    Cortazar, Ana R.; Oguiza, José A.

    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. Database URL: VerSeDa is freely available at http://genomics.cicbiogune.es/VerSeDa/index.php PMID:28365718

  20. VerSeDa: vertebrate secretome database.

    PubMed

    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.

  1. Pleistocene vertebrates of the Yukon Territory

    NASA Astrophysics Data System (ADS)

    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.

  2. Control of Vertebrate Pests of Agricultural Crops.

    ERIC Educational Resources Information Center

    Wingard, Robert G.; Studholme, Clinton R.

    This agriculture extension service publication of Pennsylvania State University discusses the damage from and control of vertebrate pests. Specific discussions describe the habits, habitat, and various control measures for blackbirds and crows, deer, meadow and pine mice, European starlings, and woodchucks. Where confusion with non-harmful species…

  3. Improved Prediction of Non-methylated Islands in Vertebrates Highlights Different Characteristic Sequence Patterns

    PubMed Central

    Vingron, Martin

    2016-01-01

    Non-methylated islands (NMIs) of DNA are genomic regions that are important for gene regulation and development. A recent study of genome-wide non-methylation data in vertebrates by Long et al. (eLife 2013;2:e00348) has shown that many experimentally identified non-methylated regions do not overlap with classically defined CpG islands which are computationally predicted using simple DNA sequence features. This is especially true in cold-blooded vertebrates such as Danio rerio (zebrafish). In order to investigate how predictive DNA sequence is of a region’s methylation status, we applied a supervised learning approach using a spectrum kernel support vector machine, to see if a more complex model and supervised learning can be used to improve non-methylated island prediction and to understand the sequence properties of these regions. We demonstrate that DNA sequence is highly predictive of methylation status, and that in contrast to existing CpG island prediction methods our method is able to provide more useful predictions of NMIs genome-wide in all vertebrate organisms that were studied. Our results also show that in cold-blooded vertebrates (Anolis carolinensis, Xenopus tropicalis and Danio rerio) where genome-wide classical CpG island predictions consist primarily of false positives, longer primarily AT-rich DNA sequence features are able to identify these regions much more accurately. PMID:27984582

  4. Search for conserved amino acid residues of the α-crystallin proteins of vertebrates.

    PubMed

    Shiliaev, Nikita G; Selivanova, Olga M; Galzitskaya, Oxana V

    2016-04-01

    [Formula: see text]-crystallin is the major eye lens protein and a member of the small heat-shock protein (sHsp) family. [Formula: see text]-crystallins have been shown to support lens clarity by preventing the aggregation of lens proteins. We performed the bioinformatics analysis of [Formula: see text]-crystallin sequences from vertebrates to find conserved amino acid residues as the three-dimensional (3D) structure of [Formula: see text]-crystallin is not identified yet. We are the first who demonstrated that the N-terminal region is conservative along with the central domain for vertebrate organisms. We have found that there is correlation between the conserved and structured regions. Moreover, amyloidogenic regions also correspond to the structured regions. We analyzed the amino acid composition of [Formula: see text]-crystallin A and B chains. Analyzing the occurrence of each individual amino acid residue, we have found that such amino acid residues as leucine, serine, lysine, proline, phenylalanine, histidine, isoleucine, glutamic acid, and valine change their content simultaneously in A and B chains in different classes of vertebrates. Aromatic amino acids occur more often in [Formula: see text]-crystallins from vertebrates than on the average in proteins among 17 animal proteomes. We obtained that the identity between A and B chains in the mammalian group is 0.35, which is lower than the published 0.60.

  5. Four-level noncontiguous fracture of the vertebral column: a case report.

    PubMed

    Acaroğlu, E R; Alanay, A

    2001-05-01

    The case of a patient with four-level fractures of the vertebral column, located at the cervical, thoracic, lumbar, and sacral regions, three of which were unstable, is reported. There were no injuries in the appendicular skeleton. Neurological involvement was potentially caused by multilevel compressions. This patient was treated aggressively with early surgical stabilization of all unstable levels, which facilitated early expeditious rehabilitation.

  6. The Evolution of Line-1 in Vertebrates.

    PubMed

    Boissinot, Stéphane; Sookdeo, Akash

    2016-10-19

    The abundance and diversity of the LINE-1 (L1) retrotransposon differ greatly among vertebrates. Mammalian genomes contain hundred of thousands L1s that have accumulated since the origin of mammals. A single group of very similar elements is active at a time in mammals, thus a single lineage of active families has evolved in this group. In contrast, non-mammalian genomes (fish, amphibians, reptiles) harbor a large diversity of concurrently transposing families, which are all represented by very small number of recently inserted copies. Why the pattern of diversity and abundance of L1 is so different among vertebrates remains unknown. To address this issue, we performed a detailed analysis of the evolution of active L1 in 14 mammals and in three non-mammalian vertebrate model species. We examined the evolution of base composition and codon bias, the general structure, and the evolution of the different domains of L1 (5'UTR, ORF1, ORF2, 3'UTR). L1s differ substantially in length, base composition and structure among vertebrates. The most variation is found in the 5'UTR, which is longer in amniotes, and in the ORF1, which tend to evolve faster in mammals. The highly divergent L1 families of lizard, frog and fish share species-specific features suggesting they are subjected to the same functional constraints imposed by their host. The relative conservation of the 5'UTR and ORF1 in non-mammalian vertebrates suggests that the repression of transposition by the host does not act in a sequence specific manner and did not result in an arms race, as is observed in mammals.

  7. The Evolution of LINE-1 in Vertebrates

    PubMed Central

    Sookdeo, Akash

    2016-01-01

    The abundance and diversity of the LINE-1 (L1) retrotransposon differ greatly among vertebrates. Mammalian genomes contain hundreds of thousands L1s that have accumulated since the origin of mammals. A single group of very similar elements is active at a time in mammals, thus a single lineage of active families has evolved in this group. In contrast, non-mammalian genomes (fish, amphibians, reptiles) harbor a large diversity of concurrently transposing families, which are all represented by very small number of recently inserted copies. Why the pattern of diversity and abundance of L1 is so different among vertebrates remains unknown. To address this issue, we performed a detailed analysis of the evolution of active L1 in 14 mammals and in 3 non-mammalian vertebrate model species. We examined the evolution of base composition and codon bias, the general structure, and the evolution of the different domains of L1 (5′UTR, ORF1, ORF2, 3′UTR). L1s differ substantially in length, base composition, and structure among vertebrates. The most variation is found in the 5′UTR, which is longer in amniotes, and in the ORF1, which tend to evolve faster in mammals. The highly divergent L1 families of lizard, frog, and fish share species-specific features suggesting that they are subjected to the same functional constraints imposed by their host. The relative conservation of the 5′UTR and ORF1 in non-mammalian vertebrates suggests that the repression of transposition by the host does not act in a sequence-specific manner and did not result in an arms race, as is observed in mammals. PMID:28175298

  8. Insect-transmitted vertebrate viruses: flaviviridae.

    PubMed

    Ludwig, G V; Iacono-Connors, L C

    1993-04-01

    The Flaviviridae include almost 70 viruses, nearly half of which have been associated with human disease. These viruses are among the most important arthropod-borne viruses worldwide and include dengue, yellow fever, and Japanese encephalitis viruses. Morbidity and mortality caused by these viruses vary, but collectively they account for millions of encephalitis, hemorrhagic fever, arthralgia, rash, and fever cases per year. Most of the members of this family are transmitted between vertebrate hosts by arthropod vectors, most commonly mosquitoes or ticks. Transmission cycles can be simple or complex depending on the hosts, vectors, the virus, and the environmental factors affecting both hosts and viruses. Replication of virus in invertebrate hosts does not seem to result in any significant pathology, which suggests a close evolutionary relationship between virus and vector. Another example of this relationship is the ability of these viruses to grow in invertebrate cell culture, where replication usually results in a steady state, persistent infection, often without cytopathic effect. Yields of virus from insect cell culture vary but are generally similar to yields in vertebrate cells. Replication kinetics are comparable between insect and vertebrate cell lines, despite differences in incubation temperature. Both vertebrate and insect cell culture systems continue to play a significant role in flavivirus isolation and the diagnosis of disease caused by these agents. Additionally, these culture systems permit the study of flavivirus attachment, penetration, replication, and release from cells and have been instrumental in the production and characterization of live-attenuated vaccines. Both vertebrate and insect cell culture systems will continue to play a significant role in basic and applied flavivirus research in the future.

  9. The Acre vertebrate fauna: Age, diversity, and geography

    NASA Astrophysics Data System (ADS)

    Cozzuol, Mario Alberto

    2006-07-01

    The vertebrate faunal assemblage associated with the Neogene deposits in the Acre region (southwestern Amazonia) is secured as Late Miocene on the basis of a correlation with the 'Mesopotamian' faunal assemblage from the Paraná region of Argentina and Uruguay. Both assemblages occur in the time span of the Huayquerian South American Land Mammal Age (SALMA). The Acre, 'Mesopotamian' (Argentina and Uruguay), and Urumaco (Venezuela) assemblages are considered faunistically correlated and contemporaneous on the basis of their shared amniote taxa. The Laventan assemblage from Colombia has important faunistic affinities with the previous three but is older. A paleogeographic scenario is proposed to explain the long-distance correlation among those assemblages. On the basis of data from geology, field observations, fauna, and palynology, the validity of the Ucayali unconformity as a time marker along all of western Amazonia is rejected.

  10. Complete nucleotide sequence of primitive vertebrate immunoglobulin light chain genes.

    PubMed Central

    Shamblott, M J; Litman, G W

    1989-01-01

    Antibody to Heterodontus francisci (horned shark) immunoglobulin light chain was used to screen a spleen cDNA expression library, and recombinant clones encoding light chain genes were isolated. The complete sequences of the mature coding regions of two light chain genes in this phylogenetically distant vertebrate have been determined and are reported here. Comparisons of the sequences are consistent with the presence of mammalian-like framework and complementarity-determining regions. The predicted amino acid sequences of the genes are more related to mammalian lambda than to kappa light chains. The nucleotide sequences of the genes are most related to mammalian T-cell antigen receptor beta chain. Heterodontus light chain genes may reflect characteristics of the common ancestor of immunoglobulin and T-cell antigen receptors before its evolutionary diversification. PMID:2499889

  11. Complete nucleotide sequence of primitive vertebrate immunoglobulin light chain genes.

    PubMed

    Shamblott, M J; Litman, G W

    1989-06-01

    Antibody to Heterodontus francisci (horned shark) immunoglobulin light chain was used to screen a spleen cDNA expression library, and recombinant clones encoding light chain genes were isolated. The complete sequences of the mature coding regions of two light chain genes in this phylogenetically distant vertebrate have been determined and are reported here. Comparisons of the sequences are consistent with the presence of mammalian-like framework and complementarity-determining regions. The predicted amino acid sequences of the genes are more related to mammalian lambda than to kappa light chains. The nucleotide sequences of the genes are most related to mammalian T-cell antigen receptor beta chain. Heterodontus light chain genes may reflect characteristics of the common ancestor of immunoglobulin and T-cell antigen receptors before its evolutionary diversification.

  12. Diversity and Community Composition of Vertebrates in Desert River Habitats

    PubMed Central

    Free, C. L.; Baxter, G. S.; Dickman, C. R.; Lisle, A.; Leung, L. K.-P.

    2015-01-01

    Animal species are seldom distributed evenly at either local or larger spatial scales, and instead tend to aggregate in sites that meet their resource requirements and maximise fitness. This tendency is likely to be especially marked in arid regions where species could be expected to concentrate at resource-rich oases. In this study, we first test the hypothesis that productive riparian sites in arid Australia support higher vertebrate diversity than other desert habitats, and then elucidate the habitats selected by different species. We addressed the first aim by examining the diversity and composition of vertebrate assemblages inhabiting the Field River and adjacent sand dunes in the Simpson Desert, western Queensland, over a period of two and a half years. The second aim was addressed by examining species composition in riparian and sand dune habitats in dry and wet years. Vertebrate species richness was estimated to be highest (54 species) in the riverine habitats and lowest on the surrounding dune habitats (45 species). The riverine habitats had different species pools compared to the dune habitats. Several species, including the agamid Gowidon longirostris and tree frog Litoria rubella, inhabited the riverine habitats exclusively, while others such as the skinks Ctenotus ariadnae and C. dux were captured only in the dune habitats. The results suggest that, on a local scale, diversity is higher along riparian corridors and that riparian woodland is important for tree-dependent species. Further, the distribution of some species, such as Mus musculus, may be governed by environmental variables (e.g. soil moisture) associated with riparian corridors that are not available in the surrounding desert environment. We conclude that inland river systems may be often of high conservation value, and that management should be initiated where possible to alleviate threats to their continued functioning. PMID:26637127

  13. Composition and Evolution of the Vertebrate and Mammalian Selenoproteomes

    PubMed Central

    Lobanov, Alexei V.; Pringle, Thomas H.; Guigo, Roderic; Hatfield, Dolph L.; Gladyshev, Vadim N.

    2012-01-01

    Background Selenium is an essential trace element in mammals due to its presence in proteins in the form of selenocysteine (Sec). Human genome codes for 25 Sec-containing protein genes, and mouse and rat genomes for 24. Methodology/Principal Findings We characterized the selenoproteomes of 44 sequenced vertebrates by applying gene prediction and phylogenetic reconstruction methods, supplemented with the analyses of gene structures, alternative splicing isoforms, untranslated regions, SECIS elements, and pseudogenes. In total, we detected 45 selenoprotein subfamilies. 28 of them were found in mammals, and 41 in bony fishes. We define the ancestral vertebrate (28 proteins) and mammalian (25 proteins) selenoproteomes, and describe how they evolved along lineages through gene duplication (20 events), gene loss (10 events) and replacement of Sec with cysteine (12 events). We show that an intronless selenophosphate synthetase 2 gene evolved in early mammals and replaced functionally the original multiexon gene in placental mammals, whereas both genes remain in marsupials. Mammalian thioredoxin reductase 1 and thioredoxin-glutathione reductase evolved from an ancestral glutaredoxin-domain containing enzyme, still present in fish. Selenoprotein V and GPx6 evolved specifically in placental mammals from duplications of SelW and GPx3, respectively, and GPx6 lost Sec several times independently. Bony fishes were characterized by duplications of several selenoprotein families (GPx1, GPx3, GPx4, Dio3, MsrB1, SelJ, SelO, SelT, SelU1, and SelW2). Finally, we report identification of new isoforms for several selenoproteins and describe unusually conserved selenoprotein pseudogenes. Conclusions/Significance This analysis represents the first comprehensive survey of the vertebrate and mammal selenoproteomes, and depicts their evolution along lineages. It also provides a wealth of information on these selenoproteins and their forms. PMID:22479358

  14. A critical appraisal of vertebral fracture assessment in paediatrics.

    PubMed

    Kyriakou, Andreas; Shepherd, Sheila; Mason, Avril; Faisal Ahmed, S

    2015-12-01

    There is a need to improve our understanding of the clinical utility of vertebral fracture assessment (VFA) in paediatrics and this requires a thorough evaluation of its readability, reproducibility, and accuracy for identifying VF. VFA was performed independently by two observers, in 165 children and adolescents with a median age of 13.4 years (range, 3.6, 18). In 20 of these subjects, VFA was compared to lateral vertebral morphometry assessment on lateral spine X-ray (LVM). 1528 (84%) of the vertebrae were adequately visualised by both observers for VFA. Interobserver agreement in vertebral readability was 94% (kappa, 0.73 [95% CI, 0.68, 0.73]). 93% of the non-readable vertebrae were located between T6 and T9. Interobserver agreement per-vertebra for the presence of VF was 99% (kappa, 0.85 [95% CI, 0.79, 0.91]). Interobserver agreement per-subject was 91% (kappa, 0.78 [95% CI, 0.66, 0.87]). Per-vertebra agreement between LVM and VFA was 95% (kappa 0.79 [95% CI, 0.62, 0.92]) and per-subject agreement was 95% (kappa, 0.88 [95% CI, 0.58, 1.0]). Accepting LVM as the gold standard, VFA had a positive predictive value (PPV) of 90% and a negative predictive value (NPV) of 95% in per-vertebra analysis and a PPV of 100% and NPV of 93% in per-subject analysis. VFA reaches an excellent level of agreement between observers and a high level of accuracy in identifying VF in a paediatric population. The readability of vertebrae at the mid thoracic region is suboptimal and interpretation at this level should be exercised with caution. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Diversity and Community Composition of Vertebrates in Desert River Habitats.

    PubMed

    Free, C L; Baxter, G S; Dickman, C R; Lisle, A; Leung, L K-P

    2015-01-01

    Animal species are seldom distributed evenly at either local or larger spatial scales, and instead tend to aggregate in sites that meet their resource requirements and maximise fitness. This tendency is likely to be especially marked in arid regions where species could be expected to concentrate at resource-rich oases. In this study, we first test the hypothesis that productive riparian sites in arid Australia support higher vertebrate diversity than other desert habitats, and then elucidate the habitats selected by different species. We addressed the first aim by examining the diversity and composition of vertebrate assemblages inhabiting the Field River and adjacent sand dunes in the Simpson Desert, western Queensland, over a period of two and a half years. The second aim was addressed by examining species composition in riparian and sand dune habitats in dry and wet years. Vertebrate species richness was estimated to be highest (54 species) in the riverine habitats and lowest on the surrounding dune habitats (45 species). The riverine habitats had different species pools compared to the dune habitats. Several species, including the agamid Gowidon longirostris and tree frog Litoria rubella, inhabited the riverine habitats exclusively, while others such as the skinks Ctenotus ariadnae and C. dux were captured only in the dune habitats. The results suggest that, on a local scale, diversity is higher along riparian corridors and that riparian woodland is important for tree-dependent species. Further, the distribution of some species, such as Mus musculus, may be governed by environmental variables (e.g. soil moisture) associated with riparian corridors that are not available in the surrounding desert environment. We conclude that inland river systems may be often of high conservation value, and that management should be initiated where possible to alleviate threats to their continued functioning.

  16. Biomonitoring of marine vertebrates in Monterey Bay using eDNA metabarcoding.

    PubMed

    Andruszkiewicz, Elizabeth A; Starks, Hilary A; Chavez, Francisco P; Sassoubre, Lauren M; Block, Barbara A; Boehm, Alexandria B

    2017-01-01

    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) versus in the deeper waters of the canyons of Monterey Bay (>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.

  17. Whole Genome Duplications Shaped the Receptor Tyrosine Kinase Repertoire of Jawed Vertebrates.

    PubMed

    Brunet, Frédéric G; Volff, Jean-Nicolas; Schartl, Manfred

    2016-06-03

    The receptor tyrosine kinase (RTK) gene family, involved primarily in cell growth and differentiation, comprises proteins with a common enzymatic tyrosine kinase intracellular domain adjacent to a transmembrane region. The amino-terminal portion of RTKs is extracellular and made of different domains, the combination of which characterizes each of the 20 RTK subfamilies among mammals. We analyzed a total of 7,376 RTK sequences among 143 vertebrate species to provide here the first comprehensive census of the jawed vertebrate repertoire. We ascertained the 58 genes previously described in the human and mouse genomes and established their phylogenetic relationships. We also identified five additional RTKs amounting to a total of 63 genes in jawed vertebrates. We found that the vertebrate RTK gene family has been shaped by the two successive rounds of whole genome duplications (WGD) called 1R and 2R (1R/2R) that occurred at the base of the vertebrates. In addition, the Vegfr and Ephrin receptor subfamilies were expanded by single gene duplications. In teleost fish, 23 additional RTK genes have been retained after another expansion through the fish-specific third round (3R) of WGD. Several lineage-specific gene losses were observed. For instance, birds have lost three RTKs, and different genes are missing in several fish sublineages. The RTK gene family presents an unusual high gene retention rate from the vertebrate WGDs (58.75% after 1R/2R, 64.4% after 3R), resulting in an expansion that might be correlated with the evolution of complexity of vertebrate cellular communication and intracellular signaling. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

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

    PubMed

    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.

  19. Whole Genome Duplications Shaped the Receptor Tyrosine Kinase Repertoire of Jawed Vertebrates

    PubMed Central

    Brunet, Frédéric G.; Volff, Jean-Nicolas; Schartl, Manfred

    2016-01-01

    The receptor tyrosine kinase (RTK) gene family, involved primarily in cell growth and differentiation, comprises proteins with a common enzymatic tyrosine kinase intracellular domain adjacent to a transmembrane region. The amino-terminal portion of RTKs is extracellular and made of different domains, the combination of which characterizes each of the 20 RTK subfamilies among mammals. We analyzed a total of 7,376 RTK sequences among 143 vertebrate species to provide here the first comprehensive census of the jawed vertebrate repertoire. We ascertained the 58 genes previously described in the human and mouse genomes and established their phylogenetic relationships. We also identified five additional RTKs amounting to a total of 63 genes in jawed vertebrates. We found that the vertebrate RTK gene family has been shaped by the two successive rounds of whole genome duplications (WGD) called 1R and 2R (1R/2R) that occurred at the base of the vertebrates. In addition, the Vegfr and Ephrin receptor subfamilies were expanded by single gene duplications. In teleost fish, 23 additional RTK genes have been retained after another expansion through the fish-specific third round (3R) of WGD. Several lineage-specific gene losses were observed. For instance, birds have lost three RTKs, and different genes are missing in several fish sublineages. The RTK gene family presents an unusual high gene retention rate from the vertebrate WGDs (58.75% after 1R/2R, 64.4% after 3R), resulting in an expansion that might be correlated with the evolution of complexity of vertebrate cellular communication and intracellular signaling. PMID:27260203

  20. Prevalent Vertebral Fractures among Children Initiating Glucocorticoid Therapy for the Treatment of Rheumatic Disorders

    PubMed Central

    Huber, A.M.; Gaboury, I.; Cabral, D.A.; Lang, B.; Ni, A.; Stephure, D.; Taback, S.; Dent, P.; Ellsworth, J.; LeBlanc, C.; Saint-Cyr, C.; Scuccimarri, R.; Hay, J.; Lentle, B.; Matzinger, M.; Shenouda, N.; Moher, D.; Rauch, F.; Siminoski, K.; Ward, L.M.

    2014-01-01

    Objectives Vertebral fractures are an under-recognized problem in children with inflammatory disorders. We studied spine health among 134 children (87 girls) with rheumatic conditions (median age 10 years) within 30 days of initiating glucocorticoid (GC) therapy. Methods Children were categorized as follows: juvenile dermatomyositis (juvenile DM, N=30), juvenile idiopathic arthritis (JIA; N=28), systemic lupus erythematosus (SLE) and related conditions (N=26), systemic arthritis (N=22), systemic vasculitis (N=16), and other conditions (N=12). Thoracolumbar spine radiograph and dual energy x-ray absorptiometry for lumbar spine areal bone mineral density (LS BMD) were performed within 30 days of GC initiation. Genant semi-quantitative grading was used for vertebral morphometry. Second metacarpal morphometry was carried out on a hand radiograph. Clinical factors including disease and physical activity, calcium and vitamin D intake, cumulative GC dose, underlying diagnosis, LS BMD Z-score and back pain were analyzed for association with vertebral fracture. Results Thirteen vertebral fractures were noted in 9 children (7%). Six patients had a single vertebral fracture and three patients had two to three fractures. Fractures were clustered in the mid-thoracic region (69%). Three vertebral fractures (23%) were moderate (Grade 2); the others were mild (Grade 1). For the entire cohort, mean (±SD) LS BMD Z-score was significantly different from zero (−0.55±1.2, p<0.001) despite a mean height Z-score that was similar to the healthy average (0.02±1.0, p=0.825). Back pain was highly associated with increased odds for fracture (OR 10.6, 95% CI 2.1 to 53.8, p=0.004). Conclusions In pediatric rheumatic conditions, vertebral fractures can be present prior to prolonged GC exposure. PMID:20391507

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

    PubMed

    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 (P<0.05). Multivariate analysis showed that the main factors influencing bone cement 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

  2. The CW domain, a structural module shared amongst vertebrates, vertebrate-infecting parasites and higher plants.

    PubMed

    Perry, Jason; Zhao, Yunde

    2003-11-01

    A previously undetected domain, named CW for its conserved cysteine and tryptophan residues, appears to be a four-cysteine zinc-finger motif found exclusively in vertebrates, vertebrate-infecting parasites and higher plants. Of the twelve distinct nuclear protein families that comprise the CW domain-containing superfamily, only the microrchida (MORC) family has begun to be characterized. However, several families contain other domains suggesting a relationship between the CW domain and either chromatin methylation status or early embryonic development.

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

    PubMed

    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.

  4. New Findings Concerning Vertebrate Porin

    NASA Astrophysics Data System (ADS)

    Thinnes, Friedrich P.; Reymann, Susanne

    Eukaryotic porin can be considered to be a good candidate for forming the channel component of the protein complex which, depending on the approach used, may realize its expression either as the outwardly-rectifying depolarization-induced chloride channel or as the volume-sensitive organic osmolyte-anion channel. As a basis for this proposition, we point to a series of correspondences in properties between mammalian porin and the ORDIC channel complex. Specifically, mammalian porin is expressed in the plasmalemma of different cells and chloride channels can be blocked by anti-human porin antibodies in astrocytes and endothelial cells. There is an indication of colocalisation of human porin and the cystic fibrosis (CF) gene product, CFTR, in the apical region of epithelial cells. The primary structure of porin from a CF patient was found to be normal. Cytosol and amniotic fluid fractions influence the channel characteristics of mammalian porin. Channel-active mammalian porin binds ATP and the stilbene disulphonate grouping of the chloride channel inhibitor DIDS. Human porin in black membranes is a pathway for taurine, and biogenic polyamines reduce the voltage dependence of human porin. Assuming the relationship between human porin and the ORDIC channel/VSOAC complex, studies on plasmalemma-integrated human porin have a relevance for CF research. In addition, we refer to a case study on a child with encephalomyopathy in which porin could not be detected using monoclonal anti-human porin antibodies. Our studies were based on purified and sequenced human porin from different cells and from different cell compartments. In addition, we raised antibodies against mature human porin or synthetic parts of the molecule. This provided a firm foundation for our topochemical work with which we were able to establish the multi-topological expression of eukaryotic porin channels. The data are summarized and discussed.

  5. Does Percutaneous Vertebroplasty or Balloon Kyphoplasty for Osteoporotic Vertebral Compression Fractures Increase the Incidence of New Vertebral Fractures? A Meta-Analysis.

    PubMed

    Zhang, Hui; Xu, Caiyuan; Zhang, Tongxing; Gao, Zhongyu; Zhang, Tao

    2017-01-01

    operation with polymethylmethacrylateand 560 who received non-operative treatments. For new-level vertebral fractures, our meta-analysis found no significant difference between the 2 methods, including total new fractures (P = 0.55) and adjacent fractures (P = 0.5). For pre-existing vertebral fractures, there was no significant difference between the 2 groups (operative and non-operative groups) (P = 0.24). Additionally,there was no significant difference in bone mineral density, both in the lumbar (P = 0 .13) and femoral neck regions (P = 0.37), between the 2 interventions. All studies we screened were published online except for unpublished articles. Moreover, only a few data sources could be extracted from the published studies.There were only 5 randomized clinical trials and 7 prospective studies that met our inclusion criteria. Vertebral augmentation techniques, such as vertebroplasty and kyphoplasty, have been widely used to treat osteoporotic vertebral fractures in order to alleviate back pain and correct the deformity, and it has been frequently reported that many new vertebral fractures occurred after this operation. Our analysis did not reveal evidence of an increased risk of fracture of vertebral bodies, especially those adjacent to the treated vertebrae, following augmentation with either method compared with conservative treatment.Key words: Vertebroplasty, kyphoplasty, new osteoporotic compression vertebral fracture, meta-analysis.

  6. Group II Intron-Mediated Trans-Splicing in the Gene-Rich Mitochondrial Genome of an Enigmatic Eukaryote, Diphylleia rotans

    PubMed Central

    Kamikawa, Ryoma; Shiratori, Takashi; Ishida, Ken-Ichiro; Miyashita, Hideaki; Roger, Andrew J.

    2016-01-01

    Although mitochondria have evolved from a single endosymbiotic event, present day mitochondria of diverse eukaryotes display a great range of genome structures, content and features. Group I and group II introns are two features that are distributed broadly but patchily in mitochondrial genomes across branches of the tree of eukaryotes. While group I intron-mediated trans-splicing has been reported from some lineages distantly related to each other, findings of group II intron-mediated trans-splicing has been restricted to members of the Chloroplastida. In this study, we found the mitochondrial genome of the unicellular eukaryote Diphylleia rotans possesses currently the second largest gene repertoire. On the basis of a probable phylogenetic position of Diphylleia, which is located within Amorphea, current mosaic gene distribution in Amorphea must invoke parallel gene losses from mitochondrial genomes during evolution. Most notably, although the cytochrome c oxidase subunit (cox) 1 gene was split into four pieces which located at a distance to each other, we confirmed that a single mature mRNA that covered the entire coding region could be generated by group II intron-mediated trans-splicing. This is the first example of group II intron-mediated trans-splicing outside Chloroplastida. Similar trans-splicing mechanisms likely work for bipartitely split cox2 and nad3 genes to generate single mature mRNAs. We finally discuss origin and evolution of this type of trans-splicing in D. rotans as well as in eukaryotes. PMID:26833505

  7. Evolution of vertebrate mechanosensory hair cells and inner ears: toward identifying stimuli that select mutation driven altered morphologies.

    PubMed

    Fritzsch, Bernd; Straka, Hans

    2014-01-01

    Among the major distance senses of vertebrates, the ear is unique in its complex morphological changes during evolution. Conceivably, these changes enable the ear to adapt toward sensing various physically well-characterized stimuli. This review develops a scenario that integrates sensory cell with organ evolution. We propose that molecular and cellular evolution of the vertebrate hair cells occurred prior to the formation of the vertebrate ear. We previously proposed that the genes driving hair cell differentiation were aggregated in the otic region through developmental re-patterning that generated a unique vertebrate embryonic structure, the otic placode. In agreement with the presence of graviceptive receptors in many vertebrate outgroups, it is likely that the vertebrate ear originally functioned as a simple gravity-sensing organ. Based on the rare occurrence of angular acceleration receptors in vertebrate outgroups, we further propose that the canal system evolved with a more sophisticated ear morphogenesis. This evolving morphogenesis obviously turned the initial otocyst into a complex set of canals and recesses, harboring multiple sensory epithelia each adapted to the acquisition of a specific aspect of a given physical stimulus. As support for this evolutionary progression, we provide several details of the molecular basis of ear development.

  8. Evolution of vertebrate mechanosensory hair cells and inner ears: toward identifying stimuli that select mutation driven altered morphologies

    PubMed Central

    Fritzsch, Bernd; Straka, Hans

    2014-01-01

    Among the major distance senses of vertebrates, the ear is unique in its complex morphological changes during evolution. Conceivably, these changes enable the ear to adapt toward sensing various physically well-characterized stimuli. This review develops a scenario that integrates sensory cell with organ evolution. We propose that molecular and cellular evolution of the vertebrate hair cells occurred prior to the formation of the vertebrate ear. We previously proposed that the genes driving hair cell differentiation, were aggregated in the otic region through developmental re-patterning that generated a unique vertebrate embryonic structure, the otic placode. In agreement with the presence of graviceptive receptors in many vertebrate outgroups, it is likely that the vertebrate ear originally functioned as a simple gravity-sensing organ. Based on the rare occurrence of angular acceleration receptors in vertebrate outgroups, we further propose that the canal system evolved with a more sophisticated ear morphogenesis. This evolving morphogenesis obviously turned the initial otocyst into a complex set of canals and recesses, harboring multiple sensory epithelia each adapted to the acquisition of a specific aspect of a given physical stimulus. As support for this evolutionary progression, we provide several details of the molecular basis of ear development. PMID:24281353

  9. New insights into the complex structure and ontogeny of the occipito-vertebral gap in barbeled dragonfishes (Stomiidae, Teleostei).

    PubMed

    Schnell, Nalani K; Britz, Ralf; Johnson, G David

    2010-08-01

    In all stomiid genera there is an occipito-vertebral gap between the skull and the first vertebra bridged only by the flexible notochord. Morphological studies from the early 20th century suggested that some stomiid genera have 1-10 of the anteriormost centra reduced or entire vertebrae missing in this region. Our study reviews this previous hypothesis. Using a new approach, we show that only in Chauliodus, Eustomias and Leptostomias gladiator vertebral centra are actually lost, with their respective neural arches and parapophyses persisting. We present results from a comparative analysis of the number and insertion sites of the anteriormost myosepta in 26 of the 28 stomiid genera. Generally in teleosts the first three myosepta are associated with the occiput, and the fourth is the first vertebral myoseptum. The insertion site of the fourth myoseptum plays an important role in this analysis, because it provides a landmark for the first vertebra. Lack of association of the fourth myoseptum with a vertebra is thus evidence that the first vertebra is reduced or absent. By counting the occipital and vertebral myosepta the number of reduced vertebrae in Chauliodus, Eustomias and Leptostomias gladiator can be inferred. Proper identification of the spino-occipital nerves provides an additional source of information about vertebral reduction. In all other stomiid genera the extensive occipito- vertebral gap is not a consequence of the reduction of vertebrae, but of an elongation of the notochord. The complex structure and ontogeny of the anterior part of the vertebral column of stomiids are discussed comparatively.

  10. The incidence of secondary vertebral fracture of vertebral augmentation techniques versus conservative treatment for painful osteoporotic vertebral fractures: a systematic review and meta-analysis.

    PubMed

    Song, Dawei; Meng, Bin; Gan, Minfeng; Niu, Junjie; Li, Shiyan; Chen, Hao; Yuan, Chenxi; Yang, Huilin

    2015-08-01

    Percutaneous vertebroplasty (PVP) and balloon kyphoplasty (BKP) are minimally invasive and effective vertebral augmentation techniques for managing osteoporotic vertebral compression fractures (OVCFs). Recent meta-analyses have compared the incidence of secondary vertebral fractures between patients treated with vertebral augmentation techniques or conservative treatment; however, the inclusions were not thorough and rigorous enough, and the effects of each technique on the incidence of secondary vertebral fractures remain unclear. To perform an updated systematic review and meta-analysis of the studies with more rigorous inclusion criteria on the effects of vertebral augmentation techniques and conservative treatment for OVCF on the incidence of secondary vertebral fractures. PubMed, MEDLINE, EMBASE, SpringerLink, Web of Science, and the Cochrane Library database were searched for relevant original articles comparing the incidence of secondary vertebral fractures between vertebral augmentation techniques and conservative treatment for patients with OVCFs. Randomized controlled trials (RCTs) and prospective non-randomized controlled trials (NRCTs) were identified. The methodological qualities of the studies were evaluated, relevant data were extracted and recorded, and an appropriate meta-analysis was conducted. A total of 13 articles were included. The pooled results from included studies showed no statistically significant differences in the incidence of secondary vertebral fractures between patients treated with vertebral augmentation techniques and conservative treatment. Subgroup analysis comparing different study designs, durations of symptoms, follow-up times, races of patients, and techniques were conducted, and no significant differences in the incidence of secondary fractures were identified (P > 0.05). No obvious publication bias was detected by either Begg's test (P = 0.360 > 0.05) or Egger's test (P = 0.373 > 0.05). Despite current thinking in the

  11. The ancestral role of nodal signalling in breaking L/R symmetry in the vertebrate forebrain.

    PubMed

    Lagadec, Ronan; Laguerre, Laurent; Menuet, Arnaud; Amara, Anis; Rocancourt, Claire; Péricard, Pierre; Godard, Benoît G; Rodicio, Maria Celina; Rodriguez-Moldes, Isabel; Mayeur, Hélène; Rougemont, Quentin; Mazan, Sylvie; Boutet, Agnès

    2015-03-30

    Left-right asymmetries in the epithalamic region of the brain are widespread across vertebrates, but their magnitude and laterality varies among species. Whether these differences reflect independent origins of forebrain asymmetries or taxa-specific diversifications of an ancient vertebrate feature remains unknown. Here we show that the catshark Scyliorhinus canicula and the lampreys Petromyzon marinus and Lampetra planeri exhibit conserved molecular asymmetries between the left and right developing habenulae. Long-term pharmacological treatments in these species show that nodal signalling is essential to their generation, rather than their directionality as in teleosts. Moreover, in contrast to zebrafish, habenular left-right differences are observed in the absence of overt asymmetry of the adjacent pineal field. These data support an ancient origin of epithalamic asymmetry, and suggest that a nodal-dependent asymmetry programme operated in the forebrain of ancestral vertebrates before evolving into a variable trait in bony fish.

  12. Treatment of iatrogenic V2 segment vertebral artery pseudoaneurysm using Pipeline flow-diverting stent

    PubMed Central

    Shakir, Hakeem J.; Rooney, Patrick J.; Rangel-Castilla, Leonardo; Yashar, Parham; Levy, Elad I.

    2016-01-01

    Background: Iatrogenic injury to the vertebral artery is a rare but potential complication of cervical spine surgery. Previous authors have commented on the use of flow-diverting stents for treatment of aneurysms of the V3 segment of the vertebral artery. Case Description: Here, we report a case in which injury occurred at the V2 segment of the vertebral artery with the development of a pseudoaneurysm, which was found on angiography. After decompressing the spinal cord from an epidural hematoma, the pseudoaneurysm was treated by deploying two Pipeline flow-diverting stents (Medtronic, Minneapolis, MN). Obliteration of the pseudoaneurysm was noted on follow-up angiography 4 days after the treatment. Conclusion: This case highlights a unique treatment at a region which, to our knowledge, has not been mentioned in the literature. PMID:28168090

  13. Early MR changes in vertebral bone marrow for patients following radiotherapy.

    PubMed

    Onu, M; Savu, M; Lungu-Solomonescu, C; Harabagiu, I; Pop, T

    2001-01-01

    Our study aimed to evaluate the vertebral marrow changes in patients following radiotherapy (RT) by measuring the T2 relaxation times before and during RT. We were mostly interested in evaluating early MR marrow changes during RT. Fifteen patients treated by RT for cervical cancer were submitted to MR examination before and during RT (5-23 days of RT). T2 values were calculated for irradiated and non-irradiated tissues (lumbar and sacral vertebral bone marrow, symphysis pubis marrow, and regional muscle). Fourteen patients presented increased T2 values for irradiated vertebral bone marrow (VBM), and 3 patients showed increased T2 values even for non-irradiated VBM. We found T2 variations for VBM as early as in the fifth day of RT for an absorbed dose as small as 9 Gy. Calculated T2 values in irradiated and also in non-irradiated tissues prove very early tissue alterations.

  14. Mid-Wisconsinan vertebrates and their environment from January Cave, Alberta, Canada

    NASA Astrophysics Data System (ADS)

    Burns, James A.

    1991-01-01

    January Cave, in the Rocky Mountains of southwestern Alberta, has yielded vertebrate remains from a coprocenosis of mid-Wisconsinan-age. Taphonomic analysis indicates accumulation by raptors, mostly owls, and mammalian carnivores. The vertebrate record, together with pollen analysis, indicates that cool, dry conditions prevailed in an extensive tundra-like environment, with prairie elements in the valleys below. Thirty-four mammalian taxa have been recovered from January Cave. Today, some of these species (e.g., Lemmus sibiricus and Dicrostonyx torquatus) do not coexist with others (e.g., Cynomys sp., Mustela nigripes, Vulpes velox, and Lagurus curtatus). Therefore, the January Cave local fauna represents a "nonanalog" mammalian community characteristic of the late Pleistocene. It suggests that the region enjoyed an equable climate, with reduced climatic extremes but still cool, further supporting a mid-Wisconsinan age estimate for the fauna. It is the first major, small vertebrate fauna of its age to be reported from Alberta.

  15. Pneumococcal Vertebral Osteomyelitis after Epidural Injection: A Rare Event

    PubMed Central

    Johnson, Tamara M; Chitturi, Chandrika; Lange, Michael; Suh, Jin S; Slim, Jihad

    2016-01-01

    Streptococcus pneumoniae vertebral infections have rarely been reported. Herein, we report a case of pneumococcal vertebral osteomyelitis with paraspinal and epidural abscesses as well as concomitant bacteremia following epidural injection. This will be the second case in the literature reporting pneumococcal vertebral osteomyelitis related to epidural manipulation. PMID:27621563

  16. The Variety of Vertebrate Mechanisms of Sex Determination

    PubMed Central

    Trukhina, Antonina V.; Lukina, Natalia A.; Wackerow-Kouzova, Natalia D.; Smirnov, Alexander F.

    2013-01-01

    The review deals with features of sex determination in vertebrates. The mechanisms of sex determination are compared between fishes, amphibians, reptilians, birds, and mammals. We focus on structural and functional differences in the role of sex-determining genes in different vertebrates. Special attention is paid to the role of estrogens in sex determination in nonmammalian vertebrates. PMID:24369014

  17. The variety of vertebrate mechanisms of sex determination.

    PubMed

    Trukhina, Antonina V; Lukina, Natalia A; Wackerow-Kouzova, Natalia D; Smirnov, Alexander F

    2013-01-01

    The review deals with features of sex determination in vertebrates. The mechanisms of sex determination are compared between fishes, amphibians, reptilians, birds, and mammals. We focus on structural and functional differences in the role of sex-determining genes in different vertebrates. Special attention is paid to the role of estrogens in sex determination in nonmammalian vertebrates.

  18. Cellular automata segmentation of the boundary between the compacta of vertebral bodies and surrounding structures

    NASA Astrophysics Data System (ADS)

    Egger, Jan; Nimsky, Christopher

    2016-03-01

    Due to the aging population, spinal diseases get more and more common nowadays; e.g., lifetime risk of osteoporotic fracture is 40% for white women and 13% for white men in the United States. Thus the numbers of surgical spinal procedures are also increasing with the aging population and precise diagnosis plays a vital role in reducing complication and recurrence of symptoms. Spinal imaging of vertebral column is a tedious process subjected to interpretation errors. In this contribution, we aim to reduce time and error for vertebral interpretation by applying and studying the GrowCut - algorithm for boundary segmentation between vertebral body compacta and surrounding structures. GrowCut is a competitive region growing algorithm using cellular automata. For our study, vertebral T2-weighted Magnetic Resonance Imaging (MRI) scans were first manually outlined by neurosurgeons. Then, the vertebral bodies were segmented in the medical images by a GrowCut-trained physician using the semi-automated GrowCut-algorithm. Afterwards, results of both segmentation processes were compared using the Dice Similarity Coefficient (DSC) and the Hausdorff Distance (HD) which yielded to a DSC of 82.99+/-5.03% and a HD of 18.91+/-7.2 voxel, respectively. In addition, the times have been measured during the manual and the GrowCut segmentations, showing that a GrowCutsegmentation - with an average time of less than six minutes (5.77+/-0.73) - is significantly shorter than a pure manual outlining.

  19. A reporter assay in lamprey embryos reveals both functional conservation and elaboration of vertebrate enhancers.

    PubMed

    Parker, Hugo J; Sauka-Spengler, Tatjana; Bronner, Marianne; Elgar, Greg

    2014-01-01

    The sea lamprey is an important model organism for investigating the evolutionary origins of vertebrates. As more vertebrate genome sequences are obtained, evolutionary developmental biologists are becoming increasingly able to identify putative gene regulatory elements across the breadth of the vertebrate taxa. The identification of these regions makes it possible to address how changes at the genomic level have led to changes in developmental gene regulatory networks and ultimately to the evolution of morphological diversity. Comparative genomics approaches using sea lamprey have already predicted a number of such regulatory elements in the lamprey genome. Functional characterisation of these sequences and other similar elements requires efficient reporter assays in lamprey. In this report, we describe the development of a transient transgenesis method for lamprey embryos. Focusing on conserved non-coding elements (CNEs), we use this method to investigate their functional conservation across the vertebrate subphylum. We find instances of both functional conservation and lineage-specific functional evolution of CNEs across vertebrates, emphasising the utility of functionally testing homologous CNEs in their host species.

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

    PubMed Central

    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

  1. Spatial memory and hippocampal pallium through vertebrate evolution: insights from reptiles and teleost fish.

    PubMed

    Rodríguez, F; López, J C; Vargas, J P; Broglio, C; Gómez, Y; Salas, C

    The forebrain of vertebrates shows great morphological variation and specialized adaptations. However, an increasing amount of neuroanatomical and functional data reveal that the evolution of the vertebrate forebrain could have been more conservative than previously realized. For example, the pallial region of the teleost telencephalon contains subdivisions presumably homologous with various pallial areas in amniotes, including possibly a homologue of the medial pallium or hippocampus. In mammals and birds, the hippocampus is critical for encoding complex spatial information to form map-like cognitive representations of the environment. Here, we present data showing that the pallial areas of reptiles and fish, previously proposed as homologous to the hippocampus of mammals and birds on an anatomical basis, are similarly involved in spatial memory and navigation by map-like or relational representations of the allocentric space. These data suggest that early in vertebrate evolution, the medial pallium of an ancestral fish group that gave rise to the extant vertebrates became specialized for processing and encoding complex spatial information, and that this functional trait has been retained through the evolution of each independent vertebrate lineage.

  2. Bone creep can cause progressive vertebral deformity.

    PubMed

    Pollintine, Phillip; Luo, Jin; Offa-Jones, Ben; Dolan, Patricia; Adams, Michael A

    2009-09-01

    Vertebral deformities in elderly people are conventionally termed "fractures", but their onset is often insidious, suggesting that time-dependent (creep) processes may also be involved. Creep has been studied in small samples of bone, but nothing is known about creep deformity of whole vertebrae, or how it might be influenced by bone mineral density (BMD). We hypothesise that sustained compressive loading can cause progressive and measurable creep deformity in elderly human vertebrae. 27 thoracolumbar "motion segments" (two vertebrae and the intervening disc and ligaments) were dissected from 20 human cadavers aged 42-91 yrs. A constant compressive force of approximately 1.0 kN was applied to each specimen for either 0.5 h or 2 h, while the anterior, middle and posterior heights of each of the 54 vertebral bodies were measured at 1 Hz using a MacReflex 2D optical tracking system. This located 6 reflective markers attached to the lateral cortex of each vertebral body, with resolution better than 10 microm. Experiments were at laboratory temperature, and polythene film was used to minimise water loss. Volumetric BMD was calculated for each vertebral body, using DXA to measure mineral content, and water immersion for volume. In the 0.5 h tests, creep deformation in the anterior, middle and posterior vertebral cortex averaged 4331, 1629 and 614 micro-strains respectively, where 10,000 micro-strains represents 1% loss in height. Anterior creep strains exceeded posterior (P<0.01) so that anterior wedging of the vertebral bodies increased, by an average 0.08 degrees (STD 0.14 degrees ). Similar results were obtained after 2 h, indicating that creep rate slowed considerably with time. Less than 40% of the creep strain was recovered after 2 h. Increases in anterior wedging during the 0.5 h creep test were inversely proportional to BMD, but only in a selected sub-set of 20 specimens with average BMD<0.15 g/cm3 (P=0.042). Creep deformation caused more than 5% height loss in

  3. Group II Intron-Mediated Trans-Splicing in the Gene-Rich Mitochondrial Genome of an Enigmatic Eukaryote, Diphylleia rotans.

    PubMed

    Kamikawa, Ryoma; Shiratori, Takashi; Ishida, Ken-Ichiro; Miyashita, Hideaki; Roger, Andrew J

    2016-02-01

    Although mitochondria have evolved from a single endosymbiotic event, present day mitochondria of diverse eukaryotes display a great range of genome structures, content and features. Group I and group II introns are two features that are distributed broadly but patchily in mitochondrial genomes across branches of the tree of eukaryotes. While group I intron-mediated trans-splicing has been reported from some lineages distantly related to each other, findings of group II intron-mediated trans-splicing has been restricted to members of the Chloroplastida. In this study, we found the mitochondrial genome of the unicellular eukaryote Diphylleia rotans possesses currently the second largest gene repertoire. On the basis of a probable phylogenetic position of Diphylleia, which is located within Amorphea, current mosaic gene distribution in Amorphea must invoke parallel gene losses from mitochondrial genomes during evolution. Most notably, although the cytochrome c oxidase subunit (cox) 1 gene was split into four pieces which located at a distance to each other, we confirmed that a single mature mRNA that covered the entire coding region could be generated by group II intron-mediated trans-splicing. This is the first example of group II intron-mediated trans-splicing outside Chloroplastida. Similar trans-splicing mechanisms likely work for bipartitely split cox2 and nad3 genes to generate single mature mRNAs. We finally discuss origin and evolution of this type of trans-splicing in D. rotans as well as in eukaryotes. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: A Systematic Review

    PubMed Central

    Pron, Gaylene; Holubowich, Corinne; Kaulback, Kellee

    2016-01-01

    Background Cancers that metastasize to the spine and primary cancers such as multiple myeloma can result in vertebral compression fractures or instability. Conservative strategies, including bed rest, bracing, and analgesic use, can be ineffective, resulting in continued pain and progressive functional disability limiting mobility and self-care. Surgery is not usually an option for cancer patients in advanced disease states because of their poor medical health or functional status and limited life expectancy. The objectives of this review were to evaluate the effectiveness and safety of percutaneous image-guided vertebral augmentation techniques, vertebroplasty and kyphoplasty, for palliation of cancer-related vertebral compression fractures. Methods We performed a systematic literature search for studies on vertebral augmentation of cancer-related vertebral compression fractures published from January 1, 2000, to October 2014; abstracts were screened by a single reviewer. For those studies meeting the eligibility criteria, full-text articles were obtained. Owing to the heterogeneity of the clinical reports, we performed a narrative synthesis based on an analytical framework constructed for the type of cancer-related vertebral fractures and the diversity of the vertebral augmentation interventions. Results The evidence review identified 3,391 citations, of which 111 clinical reports (4,235 patients) evaluated the effectiveness of vertebroplasty (78 reports, 2,545 patients) or kyphoplasty (33 reports, 1,690 patients) for patients with mixed primary spinal metastatic cancers, multiple myeloma, or hemangiomas. Overall the mean pain intensity scores often reported within 48 hours of vertebral augmentation (kyphoplasty or vertebroplasty), were significantly reduced. Analgesic use, although variably reported, usually involved parallel decreases, particularly in opioids, and mean pain-related disability scores were also significantly improved. In a randomized controlled

  5. Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: A Systematic Review.

    PubMed

    2016-01-01

    Cancers that metastasize to the spine and primary cancers such as multiple myeloma can result in vertebral compression fractures or instability. Conservative strategies, including bed rest, bracing, and analgesic use, can be ineffective, resulting in continued pain and progressive functional disability limiting mobility and self-care. Surgery is not usually an option for cancer patients in advanced disease states because of their poor medical health or functional status and limited life expectancy. The objectives of this review were to evaluate the effectiveness and safety of percutaneous image-guided vertebral augmentation techniques, vertebroplasty and kyphoplasty, for palliation of cancer-related vertebral compression fractures. We performed a systematic literature search for studies on vertebral augmentation of cancer-related vertebral compression fractures published from January 1, 2000, to October 2014; abstracts were screened by a single reviewer. For those studies meeting the eligibility criteria, full-text articles were obtained. Owing to the heterogeneity of the clinical reports, we performed a narrative synthesis based on an analytical framework constructed for the type of cancer-related vertebral fractures and the diversity of the vertebral augmentation interventions. The evidence review identified 3,391 citations, of which 111 clinical reports (4,235 patients) evaluated the effectiveness of vertebroplasty (78 reports, 2,545 patients) or kyphoplasty (33 reports, 1,690 patients) for patients with mixed primary spinal metastatic cancers, multiple myeloma, or hemangiomas. Overall the mean pain intensity scores often reported within 48 hours of vertebral augmentation (kyphoplasty or vertebroplasty), were significantly reduced. Analgesic use, although variably reported, usually involved parallel decreases, particularly in opioids, and mean pain-related disability scores were also significantly improved. In a randomized controlled trial comparing kyphoplasty

  6. Parathyroid hormone-related protein in lower vertebrates.

    PubMed

    Ingleton, P M

    2002-05-01

    The genes for parathyroid hormone-related protein (PTHrP) have been cloned in two teleost fishes, cDNA of sea bream (Sparus aurata) and genomic DNA of puffer fish (Fugu rubripes). The gene sequences show that there is significant conservation of amino acid identity, with specific domains most highly conserved. The N-terminus, responsible for bone matrix lysis in mammals and chickens, is present in the fish genes with 52% sequence identity to higher vertebrate PTHrP peptides; the nuclear transporter region shares 73% identity, and the RNA-binding sequence is 65% identical. However, the peptides are shorter then mammalian PTHrP, lacking the C-terminus responsible for inhibition of osteoclast lytic activity, but they have an additional inserted sequence between amino acids 38 and 54 that is not present in higher vertebrate PTHrPs. The N-terminus 1-38 Fugu PTHrP proved to be hypercalcaemic in larval Sparus, suggesting that it may be a physiological regulator of calcium homeostasis in fish. Using homologous nucleotide probes for in situ hybridisation and reverse-transcription polymerase chain reaction (RT-PCR) of extracted RNA, PTHrP gene expression has been widely found in both developing and adult fish. Antiserum to the fish insert sequence demonstrated transcription of PTHrP in all stages of Sparus development, and also detected the same epitope in tissues of developing frog (Rana temporaria), indicating that this has been retained during evolution of the amphibia.

  7. The vertebral column of the Regourdou 1 Neandertal.

    PubMed

    Gómez-Olivencia, Asier; Couture-Veschambre, Christine; Madelaine, Stéphane; Maureille, Bruno

    2013-06-01

    The Regourdou 1 partial skeleton was found in 1957 in level IV of the eponymous site located in Montignac-sur-Vézère (Dordogne, France) and until now it has been only partially published. The ongoing revision of the faunal remains from the site has yielded additional fossils that pertain to this skeleton. Here we study the vertebral column of this individual, providing for the first time detailed descriptions for all of the fossils and reassessing the anatomical position of all of the fragments. The vertebral column of Regourdou 1 is one of the most complete in the Neandertal fossil record with at least 20 pre-sacral vertebrae (seven cervicals, nine thoracic and four lumbars), a partial sacrum and a fragmentary first coccygeal vertebra. When compared with modern humans, the vertebrae of Regourdou 1 display significant metric differences, and fit well within the range of Neandertal variability. A preliminary analysis of the most complete thoracic vertebrae of this individual indicates that Neandertals displayed significant differences from modern humans in the thoracic spine, which adds to the differences already observed in the cervical and lumbar regions. Finally, we have also observed mild signs of osteoarthrosis, albeit to a lower degree of that present in other Neandertals such as La Chapelle-aux-Saints, La Ferrassie 1 or Shanidar 3. This is consistent with the younger adult age for Regourdou 1.

  8. Major African contributions to Palaeozoic and Mesozoic vertebrate palaeontology

    NASA Astrophysics Data System (ADS)

    Durand, J. F.

    2005-10-01

    Over more than two centuries, Africa has been an important source of knowledge with regard to the origins, evolution and distribution of important animal taxa. Not only did Africa south of the Sahara contain a second zoogeographical region virtually unknown four centuries ago, but also gave the world the first insight into the palaeontological wealth and the existence of Gondwana. The section on Agnatha includes a discussion on conodonts from South Africa, considered to be the some of the oldest and best-preserved vertebrate fossils in the world. The section on the Gnathostomata includes a very brief overview of the most important fish taxa from the Palaeozoic to Mesozoic of Africa. The section on the Tetrapoda includes an overview of the major taxa found in the fossil record of the Palaeozoic and Mesozoic of Africa. The Permian and Triassic tetrapod fossils that indicate the evolution and radiation of the parareptiles, eureptiles and synapsids are highlighted. The most important vertebrate fossils from Africa that contributed to our understanding of the radiation of evolutionary important groups such as the fish, tetrapods, tortoises, snakes, crocodiles, dinosaurs and mammals are discussed. The Jurassic and Cretaceous assemblages containing dinosaur and mammal remains, deposited after the break up of Gondwana, are discussed. Finally a perspective on the importance of Africa as fossil repository and the limitations of palaeontological endeavour in Africa is given.

  9. Dynamic epithelia of the developing vertebrate face.

    PubMed

    Choe, Chong Pyo; Crump, J Gage

    2015-06-01

    A segmental series of endoderm-derived pouch and ectoderm-derived cleft epithelia act as signaling centers in the developing face. Their precise morphogenesis is therefore essential for proper patterning of the vertebrate head. Intercellular adhesion and polarity are highly dynamic within developing facial epithelial cells, with signaling from the adjacent mesenchyme controlling both epithelial character and directional migration. Endodermal and ectodermal epithelia fuse to form the primary mouth and gill slits, which involves basement membrane dissolution, cell intercalations, and apoptosis, as well as undergo further morphogenesis to generate the middle ear cavity and glands of the neck. Recent studies of facial epithelia are revealing both core programs of epithelial morphogenesis and insights into the coordinated assembly of the vertebrate head.

  10. Population momentum across vertebrate life histories

    USGS Publications Warehouse

    Koons, D.N.; Grand, J.B.; Arnold, J.M.

    2006-01-01

    Population abundance is critically important in conservation, management, and demographic theory. Thus, to better understand how perturbations to the life history affect long-term population size, we examined population momentum for four vertebrate classes with different life history strategies. In a series of demographic experiments we show that population momentum generally has a larger effect on long-term population size for organisms with long generation times than for organisms with short generation times. However, patterns between population momentum and generation time varied across taxonomic groups and according to the life history parameter that was changed. Our findings indicate that momentum may be an especially important aspect of population dynamics for long-lived vertebrates, and deserves greater attention in life history studies. Further, we discuss the importance of population momentum in natural resource management, pest control, and conservation arenas. ?? 2006 Elsevier B.V. All rights reserved.

  11. Miocene vertebrates and North Florida shorelines

    USGS Publications Warehouse

    Olsen, S.J.

    1968-01-01

    Vertebrate fossils from ten localities, spread across northern Florida, give evidence of shorelines and deltas that have previously been established on geologic evidence or invertebrates alone. Terrestrial mammal remains, in association with shallow-water forms, indicate a deltaic assemblage and in several instances specific animals suggest restricted water depths at the time of sediment deposition. Fortunately diagnostic fragments of Miocene horses, Merychippus and Parahippus, are present in these beds, allowing for a rather close age evaluation of these sediments. Adequate fossil material has been collected from these localities to suggest the past environment and ecological conditions for the forms represented. By utilizing a suggested course of experiments with stream table apparatus it is possible to use the orientation of the fossil vertebrate remains as aids in determining past conditions of sediment accumulation. ?? 1968.

  12. Patterns and Processes of Vertebrate Evolution

    NASA Astrophysics Data System (ADS)

    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.

  13. Acute compressive myelopathy due to vertebral haemangioma.

    PubMed

    Macki, Mohamed; Bydon, Mohamad; Kaloostian, Paul; Bydon, Ali

    2014-04-28

    A 47-year-old woman with a history of anaemia presented to the emergency room with an acute onset of leg weakness. Physical examination of the bilateral lower extremities was significant for 0/5 muscle strength in all muscle groups with decreased pinprick and temperature sensation. A sensory level at the umbilicus was appreciated. Fine touch and proprioception were preserved. Bowel and bladder function were intact. CT revealed several thoracic, vertebral haemangiomatas. An MRI was suggestive of an epidural clot at the T8-T10-weighted posterior epidural space. At the level of the lesion, the cerebrospinal fluid space was completely effaced, and the flattened spinal cord exhibited signs of oedema and compressive myelopathy. The patient immediately underwent surgical decompression of the spinal cord. An epidural clot and vessel conglomeration were identified. A postoperative spinal angiogram confirmed the diagnosis of vertebral haemangioma. At 1-month follow-up, the patient regained strength and sensation.

  14. Molecular basis of vertebrate limb patterning.

    PubMed

    Tickle, Cheryll

    2002-10-15

    Mechanisms of limb development are common to all higher vertebrates. The current understanding of how vertebrate limbs develop comes mainly from studies on chick embryos, which are classical models for experimental manipulation, and mouse embryos, which can be genetically manipulated. Work on chick and mouse embryos is often complementary and has direct implications for human limb development. Analysis has moved to the molecular level, which allows direct links to genetics. Even though genes involved in limb development have been discovered by basic scientists through different routes to that taken by clinical geneticists, many of the same genes have been identified. Thus, the fields of embryology and clinical medicine increasingly converge. The next challenge will be to go back to animal models to begin to dissect how particular gene mutations lead to specific limb phenotypes.

  15. The importance of loading the periphery of the vertebral endplate

    PubMed Central

    Sutterlin, Chester; Dabirrahmani, Danè; Appleyard, Richard

    2016-01-01

    Background Commercial fusion cages typically provide support in the central region of the endplate, failing to utilize the increased compressive strength around the periphery. This study demonstrates the increase in compressive strength that can be achieved if the bony periphery of the endplate is loaded. Methods Sixteen cadaveric lumbar vertebrae (L1–L5) were randomly divided into two even groups. A different commercial mass produced implant (MPI) was allocated to each group: (I) a Polyether-ether-ketone (PEEK) anterior lumber inter-body fusion (ALIF) MPI; and (II) a titanium ALIF MPI. Uniaxial compression at a displacement rate of 0.5 mm/sec was applied to all vertebrae during two phases: (I) with the allocated MPI situated in the central region of the endplate; (II) with an aluminum plate, designed to load the bony periphery of the endplate. The failure load and mode of failure was recorded. Results From phase 1 to phase 2, the failure load increased from 1.1±0.4 to 2.9±1.4 kN for group 1; and from 1.3±1.0 to 3.0±1.9 kN for group 2. The increase in strength from phase 1 to phase 2 was statistically significant for each group (group 1: P<0.01, group 2: P<0.05, paired t-test). There was no significant difference between the groups in either phase (P>0.05, t-test). The mode of failure in phase 1 was the implant being forced through the endplate for both groups. In phase 2, the mode of failure was either a fracture of the epiphyseal rim or buckling of the side wall of the vertebral body. Conclusions Loading the periphery of the vertebral endplate achieved significant increase in compressive load capacity compared to loading the central region of the endplate. Clinically, this implies that patient-specific implants which load the periphery of the vertebral endplate could decrease the incidence of subsidence and improve surgical outcomes. PMID:27757430

  16. The Effect of Intra-Vertebral Heterogeneity in Microstructure on Vertebral Strength and Failure Patterns

    PubMed Central

    Hussein, Amira I.; Morgan, Elise F.

    2013-01-01

    Purpose The overall goal of this study was to determine the influence of intra-vertebral heterogeneity in microstructure on vertebral failure. Methods Trabecular density and microarchitecture were quantified for 32 thoracic vertebrae using micro-computed tomography (μCT)-based analyses of 4.81mm, contiguous cubes throughout the centrum. Intra-vertebral heterogeneity in density was defined as the inter-quartile range and quartile coefficient of variation of the cube densities. The vertebrae were compressed to failure to measure stiffness, strength, and toughness. Pre- and post-compression μCT images were analyzed using digital volume correlation to quantify failure patterns in the vertebrae, as defined by the distributions of residual strain. Results Failure patterns consisted of large deformations in the mid-transverse plane with concomitant endplate biconcavity and were linked to the intra-vertebral distribution of bone tissue. Low values of connectivity density and trabecular number, and high values of trabecular separation, were associated with high strains. However, local microstructural properties were not the sole determinants of failure. For instance, the mid-transverse plane experienced the highest strain (p<0.008) yet had the highest density, lowest structure model index, and lowest anisotropy (p<0.013). Accounting for the intra-vertebral heterogeneity in density improved predictions of strength and stiffness as compared to predictions based only on mean density (strength: R2 = 0.75 vs. 0.61, p<0.001; stiffness: R2 = 0.44 vs. 0.26, p=0.001). Conclusions Local variations in microstructure are associated with failure patterns in the vertebra. Non-invasive assessments of the intra-vertebral heterogeneity in density—which are feasible in clinical settings—can improve predictions of vertebral strength and stiffness. PMID:22707063

  17. Disseminated Mycobacterium chimaera Presenting as Vertebral Osteomyelitis.

    PubMed

    Moutsoglou, Daphne M; Merritt, Frank; Cumbler, Ethan

    2017-01-01

    Mycobacterium chimaera, a member of the Mycobacterium avium complex, is a slow-growing, nontuberculous mycobacterium associated with outbreaks in cardiac-surgery patients supported on heart-lung machines. We report a case of an elderly woman on chronic prednisone who presented with a six-month history of worsening chronic back pain, recurrent low-grade fevers, and weight loss. Imaging identified multilevel vertebral osteomyelitis and lumbar soft-tissue abscess. Abscess culture identified M. chimaera.

  18. The Timing of Timezyme Diversification in Vertebrates

    PubMed Central

    Cazaméa-Catalan, Damien; Besseau, Laurence; Falcón, Jack; Magnanou, Elodie

    2014-01-01

    All biological functions in vertebrates are synchronized with daily and seasonal changes in the environment by the time keeping hormone melatonin. Its nocturnal surge is primarily due to the rhythmic activity of the arylalkylamine N-acetyl transferase AANAT, which thus became the focus of many investigations regarding its evolution and function. Various vertebrate isoforms have been reported from cartilaginous fish to mammals but their origin has not been clearly established. Using phylogeny and synteny, we took advantage of the increasing number of available genomes in order to test whether the various rounds of vertebrate whole genome duplications were responsible for the diversification of AANAT. We highlight a gene secondary loss of the AANAT2 in the Sarcopterygii, revealing for the first time that the AAANAT1/2 duplication occurred before the divergence between Actinopterygii (bony fish) and Sarcopterygii (tetrapods, lobe-finned fish, and lungfish). We hypothesize the teleost-specific whole genome duplication (WDG) generated the appearance of the AANAT1a/1b and the AANAT2/2′paralogs, the 2′ isoform being rapidly lost in the teleost common ancestor (ray-finned fish). We also demonstrate the secondary loss of the AANAT1a in a Paracantopterygii (Atlantic cod) and of the 1b in some Ostariophysi (zebrafish and cave fish). Salmonids present an even more diverse set of AANATs that may be due to their specific WGD followed by secondary losses. We propose that vertebrate AANAT diversity resulted from 3 rounds of WGD followed by previously uncharacterized secondary losses. Extant isoforms show subfunctionalized localizations, enzyme activities and affinities that have increased with time since their emergence. PMID:25486407

  19. Simultaneous vertebral and subclavian artery stenting

    PubMed Central

    Tekieli, Łukasz; Machnik, Roman; Kabłak-Ziembicka, Anna; Przewłocki, Tadeusz; Paluszek, Piotr; Trystuła, Mariusz; Musiał, Robert; Dzierwa, Karolina; Pieniążek, Piotr

    2017-01-01

    Introduction Vertebrobasilar territory ischemia leads to disabling neurological symptoms and may be caused both by vertebral artery (VA) and subclavian artery (SA) stenosis. The coexisting symptomatic ipsilateral VA and proximal SA stenosis should be considered as a true bifurcation lesion for percutaneous treatment. Aim To evaluate the safety and efficacy of simultaneous angioplasty of vertebral and subclavian stenosis. Material and methods Fifteen patients (age 69.5 years, 46.7% men, all symptomatic from posterior circulation (history of stroke, transient ischemic attack, chronic ischemia symptoms)) were scheduled for simultaneous SA/VA angioplasty. Clinical and duplex ultrasound follow-up was conducted 1, 6 and 12 months after the procedure. Results The technical success rate was 100%. Single balloon-mounted stent angioplasty was performed for all VAs and for 13 (86.7%) SAs. In 4 cases a simultaneous radial and femoral approach was required. The mean North American Symptomatic Carotid Endarterectomy Trial (NASCET) VA stenosis was reduced from 88.7 ±9.7% to 5.7 ±6.8% and SA stenosis from 80 ±12.2% to 11 ±12.3% (p < 0.01). No periprocedural death, stroke, myocardial infarction or transient ischemic attack occurred. During follow-up (range: 6–107 months) in 10 of 15 (66.7%) patients relief of chronic ischemic symptoms was observed. No stroke/TIA occurred. One cardiovascular and 2 non-cardiovascular deaths were recorded. There was 1 symptomatic vertebral and 1 subclavian in-stent restenosis, and 2 cases of asymptomatic VA in-stent occlusion occurred. Conclusions Simultaneous vertebral and subclavian artery stenting is safe and effective. The restenosis rate remains at an acceptable level and it may be treated successfully with drug-eluting balloon angioplasty. In selected patients a dual radial and femoral approach may facilitate the procedure. PMID:28798785

  20. Transmission of ranavirus between ectothermic vertebrate hosts.

    PubMed

    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.

  1. Stakeholder participation in management of invasive vertebrates.

    PubMed

    Ford-Thompson, Adriana E S; Snell, Carolyn; Saunders, Glen; White, Piran C L

    2012-04-01

    Stakeholders are increasingly involved in species conservation. We sought to understand what features of a participatory conservation program are associated with its ecological and social outcomes. We conducted a case study of the management of invasive vertebrates in Australia. Invasive vertebrates are a substantial threat to Australia's native species, and stakeholder participation in their management is often necessary for their control. First, we identified potential influences on the ecological and social outcomes of species conservation programs from the literature. We used this information to devise an interview questionnaire, which we administered to managers of 34 participatory invasive-vertebrate programs. Effects of invasive species were related to program initiator (agency or citizen), reasons for use of a participatory approach, and stakeholder composition. Program initiator was also related to the participation methods used, level of governance (i.e., governed by an agency or citizens), changes in stakeholder interactions, and changes in abundance of invasive species. Ecological and social outcomes were related to changes in abundance of invasive species and stakeholder satisfaction. We identified relations between changes in the number of participants, stakeholder satisfaction, and occurrence of conflict. Potential ways to achieve ecological and social goals include provision of governmental support (e.g., funding) to stakeholders and minimization of gaps in representation of stakeholder groups or individuals to, for example, increase conflict mitigation. Our findings provide guidance for increasing the probability of achieving ecological and social objectives in management of invasive vertebrates and may be applicable to other participatory conservation programs. ©2012 Society for Conservation Biology.

  2. Some vertebrates go with the GLO.

    PubMed

    Troadec, Marie-Berengere; Kaplan, Jerry

    2008-03-21

    Most vertebrates synthesize vitamin C (ascorbate) de novo from glucose, but humans and certain other mammals cannot. In this issue, Montel-Hagen et al. (2008) demonstrate that erythrocytes from these ascorbate auxotrophs switch the preference of their glucose transporter Glut1 from glucose to dehydroascorbate (DHA), the oxidized form of vitamin C. This substrate preference switch is mediated by the membrane protein stomatin and is an evolutionary adaptation to vitamin C deficiency.

  3. The timing of Timezyme diversification in vertebrates.

    PubMed

    Cazaméa-Catalan, Damien; Besseau, Laurence; Falcón, Jack; Magnanou, Elodie

    2014-01-01

    All biological functions in vertebrates are synchronized with daily and seasonal changes in the environment by the time keeping hormone melatonin. Its nocturnal surge is primarily due to the rhythmic activity of the arylalkylamine N-acetyl transferase AANAT, which thus became the focus of many investigations regarding its evolution and function. Various vertebrate isoforms have been reported from cartilaginous fish to mammals but their origin has not been clearly established. Using phylogeny and synteny, we took advantage of the increasing number of available genomes in order to test whether the various rounds of vertebrate whole genome duplications were responsible for the diversification of AANAT. We highlight a gene secondary loss of the AANAT2 in the Sarcopterygii, revealing for the first time that the AAANAT1/2 duplication occurred before the divergence between Actinopterygii (bony fish) and Sarcopterygii (tetrapods, lobe-finned fish, and lungfish). We hypothesize the teleost-specific whole genome duplication (WDG) generated the appearance of the AANAT1a/1b and the AANAT2/2'paralogs, the 2' isoform being rapidly lost in the teleost common ancestor (ray-finned fish). We also demonstrate the secondary loss of the AANAT1a in a Paracantopterygii (Atlantic cod) and of the 1b in some Ostariophysi (zebrafish and cave fish). Salmonids present an even more diverse set of AANATs that may be due to their specific WGD followed by secondary losses. We propose that vertebrate AANAT diversity resulted from 3 rounds of WGD followed by previously uncharacterized secondary losses. Extant isoforms show subfunctionalized localizations, enzyme activities and affinities that have increased with time since their emergence.

  4. Pyogenic Vertebral Osteomyelitis in Heroin Addicts

    PubMed Central

    Fishbach, Ronald S.; Rosenblatt, Jon E.; Dahlgren, James G.

    1973-01-01

    The diagnosis of pyogenic vertebral osteomyelitis was made in seven narcotic addicts between 1967 and 1972. Vertebrae involved were either cervical or lumbar. Bacteriologic diagnosis was made in each case by percutaneous needle biopsy and aspiration. Staphylococcus aureus was cultured in two patients. Five patients had infections due to Gram-negative bacteria, including Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterobacter. All patients were cured by treatment with antibiotics and immobilization. PMID:4199351

  5. Making digit patterns in the vertebrate limb.

    PubMed

    Tickle, Cheryll

    2006-01-01

    The vertebrate limb has been a premier model for studying pattern formation - a striking digit pattern is formed in human hands, with a thumb forming at one edge and a little finger at the other. Classic embryological studies in different model organisms combined with new sophisticated techniques that integrate gene-expression patterns and cell behaviour have begun to shed light on the mechanisms that control digit patterning, and stimulate re-evaluation of the current models.

  6. Common normal variants of pediatric vertebral development that mimic fractures: a pictorial review from a national longitudinal bone health study

    PubMed Central

    Jaremko, Jacob Lester; Siminoski, Kerry; Firth, Gregory; Matzinger, Mary Ann; Shenouda, Nazih; Konji, Victor N.; Roth, Johannes; Sbrocchi, Anne Marie; Reed, Martin; O’Brien, Kathleen; Nadel, Helen; McKillop, Scott; Kloiber, Reinhard; Dubois, Josée; Coblentz, Craig; Charron, Martin; Ward, Leanne M.

    2015-01-01

    Children with glucocorticoid-treated illnesses are at risk for osteoporotic vertebral fractures and growing awareness has led to increased monitoring for these fractures. However scant literature describes developmental changes in vertebral morphology that can mimic fractures. The goal of this paper is to aid in distinguishing between normal variants and fractures. We illustrate differences using lateral spine radiographs obtained annually from children recruited to the Canada-wide STeroid-Associated Osteoporosis in the Pediatric Population (STOPP) observational study, in which 400 children with glucocorticoid-treated leukemia, rheumatic disorders, and nephrotic syndrome were enrolled near glucocorticoid initiation and followed prospectively for 6 years. Normal variants mimicking fractures exist in all regions of the spine and fall into two groups. The first group comprises variants mimicking pathological vertebral height loss, including not-yet-ossified vertebral apophyses superiorly and inferiorly which can lead to a vertebral shape easily over-interpreted as anterior wedge fracture, physiologic beaking, and spondylolisthesis associated with shortened posterior vertebral height. The second group includes variants mimicking other radiologic signs of fractures: anterior vertebral artery groove resembling an anterior buckle fracture, Cupid’s bow balloon disk morphology, Schmorl nodes mimicking concave endplate fractures, and parallax artifact resembling endplate interruption or biconcavity. If an unexpected vertebral body contour is detected, careful attention to its location, detailed morphology, and (if available) serial changes over time may clarify whether it is a fracture requiring change in management or simply a normal variant. Awareness of the variants described in this paper can improve accuracy in the diagnosis of pediatric vertebral fractures. PMID:25828359

  7. Common normal variants of pediatric vertebral development that mimic fractures: a pictorial review from a national longitudinal bone health study.

    PubMed

    Jaremko, Jacob L; Siminoski, Kerry; Firth, Gregory B; Matzinger, Mary Ann; Shenouda, Nazih; Konji, Victor N; Roth, Johannes; Sbrocchi, Anne Marie; Reed, Martin H; O'Brien, Mary Kathleen; Nadel, Helen; McKillop, Scott; Kloiber, Reinhard; Dubois, Josée; Coblentz, Craig; Charron, Martin; Ward, Leanne M

    2015-04-01

    Children with glucocorticoid-treated illnesses are at risk for osteoporotic vertebral fractures, and growing awareness of this has led to increased monitoring for these fractures. However scant literature describes developmental changes in vertebral morphology that can mimic fractures. The goal of this paper is to aid in distinguishing between normal variants and fractures. We illustrate differences using lateral spine radiographs obtained annually from children recruited to the Canada-wide STeroid-Associated Osteoporosis in the Pediatric Population (STOPP) observational study, in which 400 children with glucocorticoid-treated leukemia, rheumatic disorders, and nephrotic syndrome were enrolled near glucocorticoid initiation and followed prospectively for 6 years. Normal variants mimicking fractures exist in all regions of the spine and fall into two groups. The first group comprises variants mimicking pathological vertebral height loss, including not-yet-ossified vertebral apophyses superiorly and inferiorly, which can lead to a vertebral shape easily over-interpreted as anterior wedge fracture, physiological beaking, or spondylolisthesis associated with shortened posterior vertebral height. The second group includes variants mimicking other radiologic signs of fractures: anterior vertebral artery groove resembling an anterior buckle fracture, Cupid's bow balloon disk morphology, Schmorl nodes mimicking concave endplate fractures, and parallax artifact resembling endplate interruption or biconcavity. If an unexpected vertebral body contour is detected, careful attention to its location, detailed morphology, and (if available) serial changes over time may clarify whether it is a fracture requiring change in management or simply a normal variant. Awareness of the variants described in this paper can improve accuracy in the diagnosis of pediatric vertebral fractures.

  8. Nestedness of Ectoparasite-Vertebrate Host Networks

    PubMed Central

    Graham, Sean P.; Hassan, Hassan K.; Burkett-Cadena, Nathan D.; Guyer, Craig; Unnasch, Thomas R.

    2009-01-01

    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. PMID:19924299

  9. The Immunoglobulins of Cold-Blooded Vertebrates

    PubMed Central

    Pettinello, Rita; Dooley, Helen

    2014-01-01

    Although lymphocyte-like cells secreting somatically-recombining receptors have been identified in the jawless fishes (hagfish and lamprey), the cartilaginous fishes (sharks, skates, rays and chimaera) are the most phylogenetically distant group relative to mammals in which bona fide immunoglobulins (Igs) have been found. Studies of the antibodies and humoral immune responses of cartilaginous fishes and other cold-blooded vertebrates (bony fishes, amphibians and reptiles) are not only revealing information about the emergence and roles of the different Ig heavy and light chain isotypes, but also the evolution of specialised adaptive features such as isotype switching, somatic hypermutation and affinity maturation. It is becoming increasingly apparent that while the adaptive immune response in these vertebrate lineages arose a long time ago, it is most definitely not primitive and has evolved to become complex and sophisticated. This review will summarise what is currently known about the immunoglobulins of cold-blooded vertebrates and highlight the differences, and commonalities, between these and more “conventional” mammalian species. PMID:25427250

  10. Vertebrate Axial Patterning: From Egg to Asymmetry.

    PubMed

    Houston, Douglas W

    2017-01-01

    The emergence of the bilateral embryonic body axis from a symmetrical egg has been a long-standing question in developmental biology. Historical and modern experiments point to an initial symmetry-breaking event leading to localized Wnt and Nodal growth factor signaling and subsequent induction and formation of a self-regulating dorsal "organizer." This organizer forms at the site of notochord cell internalization and expresses primarily Bone Morphogenetic Protein (BMP) growth factor antagonists that establish a spatiotemporal gradient of BMP signaling across the embryo, directing initial cell differentiation and morphogenesis. Although the basics of this model have been known for some time, many of the molecular and cellular details have only recently been elucidated and the extent that these events remain conserved throughout vertebrate evolution remains unclear. This chapter summarizes historical perspectives as well as recent molecular and genetic advances regarding: (1) the mechanisms that regulate symmetry-breaking in the vertebrate egg and early embryo, (2) the pathways that are activated by these events, in particular the Wnt pathway, and the role of these pathways in the formation and function of the organizer, and (3) how these pathways also mediate anteroposterior patterning and axial morphogenesis. Emphasis is placed on comparative aspects of the egg-to-embryo transition across vertebrates and their evolution. The future prospects for work regarding self-organization and gene regulatory networks in the context of early axis formation are also discussed.

  11. Bisphosphonates are not associated with vertebral osteonecrosis.

    PubMed

    Kallmes, David F; Rad, Arash Ehteshami; Gray, Leigh A; McDonald, Robert J; Clarke, Bart L

    2009-01-01

    Intravertebral clefts are considered markers for osteonecrosis. We tested the hypothesis that bisphosphonate therapy was associated with vertebral osteonecrosis. A retrospective review of a vertebroplasty database was performed. Exposure to, duration of, and type of bisphosphonate therapy was documented. Radiographs were reviewed to identify intravertebral gas-filled or fluid-filled clefts, which are considered a marker for vertebral osteonecrosis. Proportion of patients with and without clefts was compared between the group exposed to bisphosphonates and the unexposed group using Chi-squared test. Duration of bisphosphonate exposure was compared between patients with and without clefts using Student's t-test. After exclusion of 16 patients with malignancy and 21 with chronic steroid therapy 237 patients were identified. Sixty-seven (28%) of the total cohort of patients were prescribed bisphosphonate therapy. Overall, clefts were present in 68 (29%) of the 237 patients. Among the 67 patients exposed to bisphosphonate therapy, 15 patients (22%) had clefts. Among the 170 patients not exposed to bisphosphonate therapy, 53 patients (31%) had clefts (P = 0.17 compared to bisphosphonate therapy group). Mean duration of bisphosphonate therapy among patients with clefts was 52 +/- 63 weeks and among patients without clefts was 57 +/- 79 weeks (P = 0.80). Intravertebral clefts are not associated with bisphosphonate therapy. If these clefts indicate osteonecrosis, then bisphosphonate therapy does not appear to be associated with vertebral osteonecrosis.

  12. Modular evolution of the Cetacean vertebral column.

    PubMed

    Buchholtz, Emily A

    2007-01-01

    Modular theory predicts that hierarchical developmental processes generate hierarchical phenotypic units that are capable of independent modification. The vertebral column is an overtly modular structure, and its rapid phenotypic transformation in cetacean evolution provides a case study for modularity. Terrestrial mammals have five morphologically discrete vertebral series that are now known to be coincident with Hox gene expression patterns. Here, I present the hypothesis that in living Carnivora and Artiodactyla, and by inference in the terrestrial ancestors of whales, the series are themselves components of larger precaudal and caudal modular units. Column morphology in a series of fossil and living whales is used to predict the type and sequence of developmental changes responsible for modification of that ancestral pattern. Developmental innovations inferred include independent meristic additions to the precaudal column in basal archaeocetes and basilosaurids, stepwise homeotic reduction of the sacral series in protocetids, and dissociation of the caudal series into anterior tail and fluke subunits in basilosaurids. The most dramatic change was the novel association of lumbar and anterior caudal vertebrae in a module that crosses the precaudal/caudal boundary. This large unit is defined by shared patterns of vertebral morphology, count, and size in all living whales (Neoceti).

  13. Flapping wing aerodynamics: from insects to vertebrates.

    PubMed

    Chin, Diana D; Lentink, David

    2016-04-01

    More than a million insects and approximately 11,000 vertebrates utilize flapping wings to fly. However, flapping flight has only been studied in a few of these species, so many challenges remain in understanding this form of locomotion. Five key aerodynamic mechanisms have been identified for insect flight. Among these is the leading edge vortex, which is a convergent solution to avoid stall for insects, bats and birds. The roles of the other mechanisms - added mass, clap and fling, rotational circulation and wing-wake interactions - have not yet been thoroughly studied in the context of vertebrate flight. Further challenges to understanding bat and bird flight are posed by the complex, dynamic wing morphologies of these species and the more turbulent airflow generated by their wings compared with that observed during insect flight. Nevertheless, three dimensionless numbers that combine key flow, morphological and kinematic parameters - the Reynolds number, Rossby number and advance ratio - govern flapping wing aerodynamics for both insects and vertebrates. These numbers can thus be used to organize an integrative framework for studying and comparing animal flapping flight. Here, we provide a roadmap for developing such a framework, highlighting the aerodynamic mechanisms that remain to be quantified and compared across species. Ultimately, incorporating complex flight maneuvers, environmental effects and developmental stages into this framework will also be essential to advancing our understanding of the biomechanics, movement ecology and evolution of animal flight.

  14. Fungal osteomyelitis with vertebral re-ossification

    PubMed Central

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

    2015-01-01

    Introduction We present a rare case of thoracic vertebral osteomyelitis secondary to pulmonary Blastomyces dermatitides. Presentation of case 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. Discussion 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. PMID:26692163

  15. The immunoglobulins of cold-blooded vertebrates.

    PubMed

    Pettinello, Rita; Dooley, Helen

    2014-11-24

    Although lymphocyte-like cells secreting somatically-recombining receptors have been identified in the jawless fishes (hagfish and lamprey), the cartilaginous fishes (sharks, skates, rays and chimaera) are the most phylogenetically distant group relative to mammals in which bona fide immunoglobulins (Igs) have been found. Studies of the antibodies and humoral immune responses of cartilaginous fishes and other cold-blooded vertebrates (bony fishes, amphibians and reptiles) are not only revealing information about the emergence and roles of the different Ig heavy and light chain isotypes, but also the evolution of specialised adaptive features such as isotype switching, somatic hypermutation and affinity maturation. It is becoming increasingly apparent that while the adaptive immune response in these vertebrate lineages arose a long time ago, it is most definitely not primitive and has evolved to become complex and sophisticated. This review will summarise what is currently known about the immunoglobulins of cold-blooded vertebrates and highlight the differences, and commonalities, between these and more "conventional" mammalian species.

  16. Medical Treatment of Osteoporotic Vertebral Fractures

    PubMed Central

    Langdahl, Bente Lomholt; Harsløf, Torben

    2011-01-01

    A vertebral fracture is a serious symptom of osteoporosis. Vertebral fractures cause moderate-to-severe back pain for a shorter or longer duration, increase the risk of a subsequent vertebral fracture approximately four-fold, reduce quality of life significantly and are associated with increased mortality. In order to choose the optimal treatment for the patient, the severity and type of osteoporosis should be investigated. Prevention of new osteoporotic fractures can be accomplished through treatment with both antiresorptive and anabolic treatments. The antiresorptive treatment modalities comprise calcium, vitamin D, bisphosphonates, hormone therapy, selective oestrogen receptor modulators (SERMs), strontium ranelate, receptor activator of NF-kB ligand (RANKL) antibody and calcitonin. The anabolic treatments comprise teriparatide and parathyroid hormone [(PTH)-(1–84)]. Adherence with treatment of osteoporosis is generally poor and therefore once the choice of treatment has been made and the patient has been instructed properly, long-term adherence to the treatment should be secured through information and regular control visits. PMID:22870463

  17. Can infant malnutrition cause adult vertebral stenosis?

    PubMed

    Clark, G A; Panjabi, M M; Wetzel, F T

    1985-03-01

    Does infant malnutrition produce smaller adult spinal canals? Lumbar and thoracic vertebrae (n X 1073), from a prehistoric American Indian population (15-55 yrs of age), were measured for anteroposterior (AP) and transverse (TR) vertebral canal sizes, nerve root tunnel (intervertebral foramen) widths (NRT), vertebral heights (VH), vertebral osteophytosis (VO), and tibial lengths. They underwent a dietary change from hunting-gathering, protein rich (PR), to maize agriculture, protein deficient (PD), between 950 and 1300 A.D. Multivariate analyses controlled for age, sex, culture, NRT, VH, VO, and wedging. Canal size was significantly smaller in the PD. AP diameters were generally and highly correlated with NRT, and thus both spinal stenosis and sciatica may have a developmental basis. Canal size was independent of statural components. Consequently, canal size is a most powerful tool in assessing the presence infant malnutrition. Moreover, perhaps the association between canal size and low-back pain (LBP) found in living populations has been underestimated, and this component of LBP is preventable.

  18. The orientation of the cervical vertebral column in unrestrained awake animals. I. Resting position.

    PubMed

    Vidal, P P; Graf, W; Berthoz, A

    1986-01-01

    The orientation of the cervical vertebral column was studied by X-ray photography of the region containing the head and the neck in nine unrestrained species of vertebrates (man, monkey, cat, rabbit, guinea pig, rat, chicken, frog, lizard). In addition, the orientation of the horizontal semicircular canals was measured in four species using landmarks on the skull. In all vertebrates studied, with the exception of frog and lizard, the general orientation of the cervical vertebral column was vertical when animals were at rest, and not horizontal or oblique as suggested by the macroscopic appearance of the neck. The posture of the animal, whether lying, sitting or standing, had little effect on this general vertical orientation, although some variability was noticed depending on the species. This finding prompted the definition of a resting zone, where the cervical column can take any orientation within a narrow range around a mean position. The cervical vertebral column composes part of the S-shaped structure of the entire vertebral column, with one inflection around the cervico-thoracic (C7/Th1) junction. This feature is already noticable in the lizard. The vertical orientation of the cervical vertebral column is interpreted to provide a stable and energy saving balance of the head. Furthermore, when the head is lowered or raised, the atlanto-occipital and cervico-thoracic junctions are predominantly involved, while the entire cervical column largely preserves its intrinsic configuration. The curved configuration of the cervico-thoracic vertebral column embedded in long spring-like muscles is interpreted to function as a shock absorber. At rest, animals did not hold their heads with the horizontal canals oriented earth horizontally all the time, but often maintained them pitched up by ca. 5 deg, as has been reported for man. At other times, presumably when the vigilance level increased, the horizontal canals were brought into the earth horizontal plane. The vertical

  19. New forensic anthropological approachment for the age determination of human fetal skeletons on the base of morphometry of vertebral column.

    PubMed

    Kósa, F; Castellana, C

    2005-01-17

    The anthropometrical study was carried out on 107 human fetal/newborn skeletons (54 male, 43 female, and 9 of unknown sex). The age of the individuals ranged from 4 to 10 lunar months. Each fetal or newborn vertebral region (cervical, thoracal and lumbar) has its own distinguishing features that are easily identifiable even in fragmentary bones. With our large sample size and extension of the age range studied, we are able to determine the fetal age with a considerable degree of accuracy from measurements defined in the vertebral ossification centers using regression equations. A simple rapid method for the identification and classification of fetal vertebral column bones has been contributed. The identification and classifications were carried out using discriminant functions. Knowledge of changes in vertebral column bones during fetal development is important in applied contexts of forensic and anthropology researches.

  20. A Classification System for the Spread of Polymethyl Methacrylate in Vertebral Bodies Treated with Vertebral Augmentation

    PubMed Central

    Frankl, Joseph; Sakata, Michael P.; Choudhary, Gagandeep; Hur, Seung; Peterson, Andrew; Hennemeyer, Charles T.

    2016-01-01

    In this study, we develop a classification system for describing polymethyl methacrylate (PMMA) spread in vertebral bodies after kyphoplasty or vertebroplasty for vertebral compression fractures (VCFs) and for assessing whether PMMA spread varies between operators, VCF etiology, or vertebral level. Intraoperative fluoroscopic images of 198 vertebral levels were reviewed in 137 patients (women, 84; men, 53; mean age, 75.8 ± 12.5; and those with a diagnosis of osteoporosis, 63%) treated with kyphoplasty between January 01, 2015 and May 31, 2015 at a single center to create a 5-class descriptive system. PMMA spread patterns in the same images were then classified by 2 board-certified radiologists, and a third board-certified radiologist resolved conflicts. A total of 2 primary PMMA spread patterns were identified, namely, acinar and globular, with subtypes of localized acinar, diffuse globular, and mixed, to describe an equal combination of patterns. Interrater reliability using the system was moderate (κ = 0.47). After resolving conflicts, the most common spread class was globular (n = 63), followed by mixed (n = 58), diffuse globular (n = 30), acinar (n = 27), and localized acinar (n = 20). The spread class after treatment by the 2 most frequent operators differed significantly (n1 = 63, n2 = 70; P < .0001). There was no difference in the spread class between VCF etiologies or vertebral levels. PMMA spread may, therefore, be a modifiable parameter that affects kyphoplasty and vertebroplasty efficacy and adverse events. PMID:27795998

  1. Vertebral augmentation in the treatment of vertebral compression fractures: review and new insights from recent studies.

    PubMed

    Itshayek, Eyal; Miller, Peter; Barzilay, Yair; Hasharoni, Amir; Kaplan, Leon; Fraifeld, Shifra; Cohen, José E

    2012-06-01

    Vertebral compression fractures (VCF) due to osteoporotic degeneration and metastatic disease represent an increasingly significant public health problem. Percutaneous vertebroplasty (VP) began as a simple, low-cost procedure that aimed to provide pain relief for patients with VCF. Balloon kyphoplasty (KP) was introduced later, and was presented not only as a "pain killer," but also as a deformity correction procedure. The preponderance of evidence has shown that vertebral augmentation provides significant and sustained clinical benefit for patients with VCF. The debate raised by studies published in the New England Journal of Medicine comparing VP with a sham procedure highlights the importance of very careful patient selection for vertebral augmentation procedures, since osteoporotic VCF is usually a self-limiting condition. However, vertebral augmentation may be beneficial in patients with comorbidities that make prolonged bed rest dangerous, in patients with fractures that fail to heal, and in patients with painful VCF due to metastatic disease. Patient selection should be based on a combination of clinical and radiological indications. We review recent studies in the extensive literature on vertebral augmentation, with the goal of clarifying some of the controversy surrounding these procedures. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Surgical treatment of aggressive vertebral hemangiomas.

    PubMed

    Vasudeva, Viren S; Chi, John H; Groff, Michael W

    2016-08-01

    OBJECTIVE Vertebral hemangiomas are common tumors that are benign and generally asymptomatic. Occasionally these lesions can exhibit aggressive features such as bony expansion and erosion into the epidural space resulting in neurological symptoms. Surgery is often recommended in these cases, especially if symptoms are severe or rapidly progressive. Some surgeons perform decompression alone, others perform gross-total resection, while others perform en bloc resection. Radiation, embolization, vertebroplasty, and ethanol injection have also been used in combination with surgery. Despite the variety of available treatment options, the optimal management strategy is unclear because aggressive vertebral hemangiomas are uncommon lesions, making it difficult to perform large trials. For this reason, the authors chose instead to report their institutional experience along with a comprehensive review of the literature. METHODS A departmental database was searched for patients with a pathological diagnosis of "hemangioma" between 2008 and 2015. Medical records were reviewed to identify patients with aggressive vertebral hemangiomas, and these cases were reviewed in detail. RESULTS Five patients were identified who underwent surgery for treatment of aggressive vertebral hemangiomas during the specified time period. There were 2 lumbar and 3 thoracic lesions. One patient underwent en bloc spondylectomy, 2 patients had piecemeal gross-total resection, and the remaining 2 had subtotal tumor resection. Intraoperative vertebroplasty was used in 3 cases to augment the anterior column or to obliterate residual tumor. Adjuvant radiation was used in 1 case where there was residual tumor as well. The patient who underwent en bloc spondylectomy experienced several postoperative complications requiring additional medical care and reoperation. At an average follow-up of 31 months (range 3-65 months), no patient had any recurrence of disease and all were clinically asymptomatic, except the

  3. Prevalence of Vertebral Fractures in Children with Suspected Osteoporosis.

    PubMed

    Kyriakou, Andreas; Shepherd, Sheila; Mason, Avril; Ahmed, S Faisal

    2016-12-01

    To explore the prevalence and anatomic distribution of vertebral fractures in disease groups investigated for primary and secondary osteoporosis, using vertebral fracture assessment (VFA). VFA was performed independently by 2 nonradiologists, in 165 children (77 males, 88 females) as part of their investigation for osteoporosis. Vertebral bodies from T6 to L4 were assessed for vertebral fractures using the Genant scoring system. The common readings for the presence of vertebral fractures were used for evaluating the prevalence and anatomic distribution of vertebral fractures. The median age of the subjects was 13.4 years (range, 3.6, 18). Of the 165 children, 24 (15%) were being investigated for primary bone disease, and the remainder had a range of chronic diseases known to affect bone health. Vertebral fractures were identified in 38 (23%) children. The distribution of the vertebral fractures was bimodal, with vertebral fractures peaks centered at T9 and L4. Conditions associated with increased odds for vertebral fractures were inflammatory bowel disease (OR, 3.3; 95% CI, 1.4, 8.0; P = .018) and osteogenesis imperfecta (OR, 2.3; 95% CI, 1.04, 5.8; P = .022). Among children with vertebral fractures, those with Duchenne muscular dystrophy (P = .015) and osteogenesis imperfecta (P = .023) demonstrated higher number of vertebral fractures than the other disease groups. VFA identified the presence of vertebral fractures, in a bimodal distribution, in both primary bone disease and chronic disease groups. VFA is a practical screening tool for identification of vertebral fractures in children and adolescents at risk of fragility fractures. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Regulation of cell polarity and RNA localization in vertebrate oocytes.

    PubMed

    Houston, Douglas W

    2013-01-01

    It has long been appreciated that the inheritance of maternal cytoplasmic determinants from different regions of the egg can lead to differential specification of blastomeres during cleavage. Localized RNAs are important determinants of cell fate in eggs and embryos but are also recognized as fundamental regulators of cell structure and function. This chapter summarizes recent molecular and genetic experiments regarding: (1) mechanisms that regulate polarity during different stages of vertebrate oogenesis, (2) pathways that localize presumptive protein and RNA determinants within the polarized oocyte and egg, and (3) how these determinants act in the embryo to determine the ultimate cell fates. Emphasis is placed on studies done in Xenopus, where extensive work has been done in these areas, and comparisons are drawn with fish and mammals. The prospects for future work using in vivo genome manipulation and other postgenomic approaches are also discussed. © 2013 Elsevier Inc. All rights reserved.

  5. Radiation effects in wild terrestrial vertebrates - the EPIC collection.

    PubMed

    Sazykina, Tatiana; Kryshev, Ivan I

    2006-01-01

    The paper presents data on radiation effects in populations of wild vertebrate animals inhabiting contaminated terrestrial ecosystems. The data were extracted from the database "Radiation effects on biota", compiled within the framework of the EC Project EPIC (2000-2003). The data collection, based on publications in Russian, demonstrates radiation effects in the areas characterized with high levels of radionuclides (Kyshtym radioactive trace; "spots" of enhanced natural radioactivity in the Komi region of Russia; territories contaminated from the Chernobyl fallout). The data covers a wide range of exposures from acute accidental irradiation to lifetime exposures at relatively low dose rates. Radiation effects include mortality, changes in reproduction, decrease of health, ecological effects, cytogenetic effects, adaptation to radiation, and others. Peculiarities of radiation effects caused by different radionuclides are described, also the severity of effects as they appear in different organisms (e.g. mice, frogs, birds, etc.).

  6. The investigation of vertebral injury sustained during aircrew ejection

    NASA Technical Reports Server (NTRS)

    Benedict, J. V.

    1972-01-01

    A series of tests were performed on excised human vertebral segments to determine the static and dynamic response of the thoraco-lumbar spine when loaded in flexion. A total of fifteen tests were performed on eleven specimens. Specimens were obtained from male donors ranging in age from 34 to 60 years. Demographic data pertinent to each specimen and the elapsed time between death of the donor and testing of each corresponding specimen are presented. Only spinal segments comprised of lower thoracic and upper lumbar vertebrae were tested because in aircraft ejection injuries clinical complications in this anatomical region predominate. A complex continuum mathematical model describing the dynamic response of the human spine was formulated, solved, and verified experimentally. Detailed results are presented in figures, tables, and equations.

  7. Vertebral fracture assessment in patients presenting with a non-hip non-vertebral fragility fracture: experience of a UK Fracture Liaison Service.

    PubMed

    Reniu, Aina Capdevila; Ong, Terence; Ajmal, Syed; Sahota, Opinder

    2017-12-01

    Twenty-five percent of patients with a non-hip non-vertebral fragility fracture have an undiagnosed vertebral fracture detected by vertebral fracture assessment during bone densitometric assessment. The prevalence of an undiagnosed vertebral fracture is higher in older people, and they are more likely to have multiple vertebral fractures.

  8. The effect of thoracic kyphosis and sagittal plane alignment on vertebral compressive loading

    PubMed Central

    Bruno, Alexander G.; Anderson, Dennis E.; D’Agostino, John; Bouxsein, Mary L.

    2012-01-01

    To better understand the biomechanical mechanisms underlying the association between hyperkyphosis of the thoracic spine and risk of vertebral fracture and other degenerative spinal pathology, we used a previously validated musculoskeletal model of the spine to determine how thoracic kyphosis angle and spinal posture affect vertebral compressive loading. We simulated an age-related increase in thoracic kyphosis (T1-T12 Cobb angle 50° to 75°) during two different activities (relaxed standing and standing with 5 kg weights in the hands) and three different posture conditions: 1) an increase in thoracic kyphosis with no postural adjustment (uncompensated posture), 2) an increase in thoracic kyphosis with a concomitant increase in pelvic tilt that maintains a stable center of mass and horizontal eye gaze (compensated posture), and 3) an increase in thoracic kyphosis with a concomitant increase in lumbar lordosis that also maintains a stable center of mass and horizontal eye gaze (congruent posture). For all posture conditions, compressive loading increased with increasing thoracic kyphosis, with loading increasing more in the thoracolumbar and lumbar regions than in the mid-thoracic region. Loading increased the most for the uncompensated posture, followed by the compensated posture, with the congruent posture almost completely mitigating any increases in loading with increased thoracic kyphosis. These findings indicate that thoracic kyphosis and spinal posture both influence vertebral loading during daily activities, implying that thoracic kyphosis measurements alone are not sufficient to characterize the impact of spinal curvature on vertebral loading. PMID:22589006

  9. Comparative morphometric study of the australopithecine vertebral series Stw-H8/H41.

    PubMed

    Sanders, W J

    1998-03-01

    Lower spinal structure correlates well with positional behavior among mammals. Nonetheless, the functional morphology of the axial post-crania of australopithecines has received less attention than their appendicular skeletons. This paper presents a detailed description and comparative morphometric analysis of the australopithecine thoracolumbar vertebral series Stw-H8/H41, and examines spinal mechanics in early hominids. Stw-H8/H41 is an important specimen, as the australopithecine vertebral sample is small, and vertebral series are more useful than isolated elements for the interpretation of spinal function. Results of the study support the interpretation that australopithecine species are highly sexually dimorphic. The study also reveals a considerable amount of morphometric variation other than size among australopithecine vertebrae, though the sample is too small and incomplete to ascertain whether this indicates significant interspecific differences in spinal function. Most importantly, structural and metric observations confirm that the morphology of the lower spine in australopithecines has no modern analogue in its entirety. Aspects of zygapophyseal structure, numerical composition of the lumbar region, and centrum wedging suggest that the australopithecine vertebral column was adapted to human-like intrinsic lumbar lordosis and stable balance of the trunk over the pelvis in sustained bipedal locomotion. However, relative centrum size in australopithecines indicates that either they had a different mechanism for channeling vertical forces through the vertebral column than humans, or differed behaviorally from humans in ways that produced smaller increments of compression across their centra. These findings have important implications for hypotheses of australopithecine positional behavior, and demonstrate that larger samples and more complete vertebral series are needed to improve our understanding of australopithecine spinal function.

  10. A Hox regulatory network of hindbrain segmentation is conserved to the base of vertebrates.

    PubMed

    Parker, Hugo J; Bronner, Marianne E; Krumlauf, Robb

    2014-10-23

    A defining feature governing head patterning of jawed vertebrates is a highly conserved gene regulatory network that integrates hindbrain segmentation with segmentally restricted domains of Hox gene expression. Although non-vertebrate chordates display nested domains of axial Hox expression, they lack hindbrain segmentation. The sea lamprey, a jawless fish, can provide unique insights into vertebrate origins owing to its phylogenetic position at the base of the vertebrate tree. It has been suggested that lamprey may represent an intermediate state where nested Hox expression has not been coupled to the process of hindbrain segmentation. However, little is known about the regulatory network underlying Hox expression in lamprey or its relationship to hindbrain segmentation. Here, using a novel tool that allows cross-species comparisons of regulatory elements between jawed and jawless vertebrates, we report deep conservation of both upstream regulators and segmental activity of enhancer elements across these distant species. Regulatory regions from diverse gnathostomes drive segmental reporter expression in the lamprey hindbrain and require the same transcriptional inputs (for example, Kreisler (also known as Mafba), Krox20 (also known as Egr2a)) in both lamprey and zebrafish. We find that lamprey hox genes display dynamic segmentally restricted domains of expression; we also isolated a conserved exonic hox2 enhancer from lamprey that drives segmental expression in rhombomeres 2 and 4. Our results show that coupling of Hox gene expression to segmentation of the hindbrain is an ancient trait with origin at the base of vertebrates that probably led to the formation of rhombomeric compartments with an underlying Hox code.

  11. Alternative approaches for vertebrate ecotoxicity tests in the ...

    EPA Pesticide Factsheets

    The need for alternative approaches to the use of vertebrate animals for hazard assessing chemicals and pollutants has become of increasing importance. It is now the first consideration when initiating a vertebrate ecotoxicity test, to ensure that unnecessary use of vertebrate organisms is minimised wherever possible. For some regulatory purposes, the use of vertebrate organisms for environmental risk assessments (ERA) has even been banned, and in other situations the numbers of organisms tested has been dramatically reduced, or the severity of the procedure refined. However, there is still a long way to go to achieve replacement of vertebrate organisms to generate environmental hazard data. The development of animal alternatives is not just based on ethical considerations but also to reduce the cost of performing vertebrate ecotoxicity tests and in some cases to provide better information aimed at improving ERAs. The present focus paper provides an overview of the considerable advances that have been made towards alternative approaches for ecotoxicity assessments over the last few decades. The need for alternative approaches to the use of vertebrate animals for hazard assessing chemicals and pollutants has become of increasing importance. It is now the first consideration when initiating a vertebrate ecotoxicity test, to ensure that unnecessary use of vertebrate organisms is minimised wherever possible. For some regulatory purposes, the use of vertebrate organi

  12. Influence of physical activity on vertebral strength during late adolescence.

    PubMed

    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.

  13. Evolution of vertebrate forebrain development: how many different mechanisms?

    PubMed Central

    FOLEY, ANN C.; STERN, CLAUDIO D.

    2001-01-01

    Over the past 50 years and more, many models have been proposed to explain how the nervous system is initially induced and how it becomes subdivided into gross regions such as forebrain, midbrain, hindbrain and spinal cord. Among these models is the 2-signal model of Nieuwkoop & Nigtevecht (1954), who suggested that an initial signal (‘activation’) from the organiser both neuralises and specifies the forebrain, while later signals (‘transformation’) from the same region progressively caudalise portions of this initial territory. An opposing idea emerged from the work of Otto Mangold (1933) and other members of the Spemann laboratory: 2 or more distinct organisers, emitting different signals, were proposed to be responsible for inducing the head, trunk and tail regions. Since then, evidence has accumulated that supports one or the other model, but it has been very difficult to distinguish between them. Recently, a considerable body of work from mouse embryos has been interpreted as favouring the latter model, and as suggesting that a ‘head organiser’, required for the induction of the forebrain, is spatially separate from the classic organiser (Hensen's node). An extraembryonic tissue, the ‘anterior visceral endoderm’ (AVE), was proposed to be the source of forebrain-inducing signals. It is difficult to find tissues that are directly equivalent embryologically or functionally to the AVE in other vertebrates, which led some (e.g. Kessel, 1998) to propose that mammals have evolved a new way of patterning the head. We will present evidence from the chick embryo showing that the hypoblast is embryologically and functionally equivalent to the mouse AVE. Like the latter, the hypoblast also plays a role in head development. However, it does not act like a true organiser. It induces pre-neural and pre-forebrain markers, but only transiently. Further development of neural and forebrain phenotypes requires additional signals not provided by the hypoblast. In

  14. Vertebral Body Growth After Craniospinal Irradiation

    SciTech Connect

    Hartley, Katherine A.; Li Chenghong; Laningham, Fred H.; Krasin, Matthew J.; Xiong Xiaoping; Merchant, Thomas E.

    2008-04-01

    Purpose: To estimate the effects of radiotherapy and clinical factors on vertebral growth in patients with medulloblastoma and supratentorial primitive neuroectodermal tumors treated with craniospinal irradiation (CSI) and chemotherapy. Methods and Materials: The height of eight individual or grouped vertebral bodies (C3, C3-C4, T4, T4-T5, C6-T3, T4-T7, L3, L1-L5) was measured before and after CSI (23.4 or 36-39.6 Gy) in 61 patients. Of the 61 patients, 40 were boys and 21 were girls (median age, 7 years; range, 3-13 years), treated between October 1996 and October 2003. Sagittal T{sub 1}-weighted magnetic resonance images were used for the craniocaudal measurements. The measurements numbered 275 (median, 5/patient; range, 3-7). The median follow-up after CSI was 44.1 months (range, 13.8-74.9 months). Results: Significant growth was observed in all measured vertebrae. Excluding C3-C4, the growth rate of the grouped vertebrae was affected by age, gender, and CSI dose (risk classification). The risk classification alone affected the growth rates of C3 (p = 0.002) and L3 (p = 0.02). Before CSI, the length of all vertebral bodies was an increasing function of age (p <0.0001). The C3 length before CSI was affected by gender and risk classification: C3 was longer for female (p = 0.07) and high-risk (p = 0.07) patients. Conclusion: All vertebrae grew significantly after CSI, with the vertebrae of the boys and younger patients growing at a rate greater than that of their counterparts. The effect of age was similar across all vertebrae, and gender had the greatest effect on the growth of the lower cervical and upper thoracic vertebrae. The effect of the risk classification was greatest in the lumbar spine by a factor of {<=}10.

  15. DEVELOPMENTAL PALEOBIOLOGY OF THE VERTEBRATE SKELETON

    PubMed Central

    RÜCKLIN, MARTIN; DONOGHUE, PHILIP C. J.; CUNNINGHAM, JOHN A.; MARONE, FEDERICA; STAMPANONI, MARCO

    2015-01-01

    Studies of the development of organisms can reveal crucial information on homology of structures. Developmental data are not peculiar to living organisms, and they are routinely preserved in the mineralized tissues that comprise the vertebrate skeleton, allowing us to obtain direct insight into the developmental evolution of this most formative of vertebrate innovations. The pattern of developmental processes is recorded in fossils as successive stages inferred from the gross morphology of multiple specimens and, more reliably and routinely, through the ontogenetic stages of development seen in the skeletal histology of individuals. Traditional techniques are destructive and restricted to a 2-D plane with the third dimension inferred. Effective non-invasive methods of visualizing paleohistology to reconstruct developmental stages of the skeleton are necessary. In a brief survey of paleohistological techniques we discuss the pros and cons of these methods. The use of tomographic methods to reconstruct development of organs is exemplified by the study of the placoderm dentition. Testing evidence for the presence of teeth in placoderms, the first jawed vertebrates, we compare the methods that have been used. These include inferring the development from morphology, and using serial sectioning, microCT or synchrotron X-ray tomographic microscopy (SRXTM) to reconstruct growth stages and directions of growth. The ensuing developmental interpretations are biased by the methods and degree of inference. The most direct and reliable method is using SRXTM data to trace sclerochronology. The resulting developmental data can be used to resolve homology and test hypotheses on the origin of evolutionary novelties. PMID:26306050

  16. Evolution of Vertebrate Phototransduction: Cascade Activation

    PubMed Central

    Lamb, Trevor D.; Patel, Hardip; Chuah, Aaron; Natoli, Riccardo C.; Davies, Wayne I. L.; Hart, Nathan S.; Collin, Shaun P.; Hunt, David M.

    2016-01-01

    We applied high-throughput sequencing to eye tissue from several species of basal vertebrates (a hagfish, two species of lamprey, and five species of gnathostome fish), and we analyzed the mRNA sequences for the proteins underlying activation of the phototransduction cascade. The molecular phylogenies that we constructed from these sequences are consistent with the 2R WGD model of two rounds of whole genome duplication. Our analysis suggests that agnathans retain an additional representative (that has been lost in gnathostomes) in each of the gene families we studied; the evidence is strong for the G-protein α subunit (GNAT) and the cGMP phosphodiesterase (PDE6), and indicative for the cyclic nucleotide-gated channels (CNGA and CNGB). Two of the species (the hagfish Eptatretus cirrhatus and the lamprey Mordacia mordax) possess only a single class of photoreceptor, simplifying deductions about the composition of cascade protein isoforms utilized in their photoreceptors. For the other lamprey, Geotria australis, analysis of the ratios of transcript levels in downstream and upstream migrant animals permits tentative conclusions to be drawn about the isoforms used in four of the five spectral classes of photoreceptor. Overall, our results suggest that agnathan rod-like photoreceptors utilize the same GNAT1 as gnathostomes, together with a homodimeric PDE6 that may be agnathan-specific, whereas agnathan cone-like photoreceptors utilize a GNAT that may be agnathan-specific, together with the same PDE6C as gnathostomes. These findings help elucidate the evolution of the vertebrate phototransduction cascade from an ancestral chordate phototransduction cascade that existed prior to the vertebrate radiation. PMID:27189541

  17. Life-long accumulation of 137Cs and 40K in the vertebral column of a cow.

    PubMed

    Pichl, Elke; Rabitsch, Herbert

    2013-01-01

    We have investigated the accumulation of (137)Cs and (40)K in all the tissues and organs of an adult slaughtered Austrian "mountain pasture cow". In this paper we present measured (137)Cs- and (40)K-activity concentrations in different tissues of the vertebral bodies, in their other bony components and in all the vertebrae forming the vertebral column. Data are also given for activity concentrations of adherent tissues, and for activities of both the components and the whole vertebral column. The dairy cow was born in a highly contaminated region of Styria, Austria, at the time of the radioactive fallout following the Chernobyl accident. Both radionuclides were incorporated during life-long ingestion and their accumulation in all the vertebrae up to the day of slaughtering was determined by high-purity germanium detectors. Our results show considerable variations of (137)Cs- and (40)K-activity concentrations in the components of a certain vertebra, within vertebrae of a particular region, and between vertebrae of different regions of the vertebral column. Particularly, the courses of (137)Cs- and (40)K-activity concentrations in trabecular bone, cortical bone and intervertebral discs of thoracic vertebral bodies are subdivided by a strong drop into two sections. Mean values of (137)Cs-concentration in vertebral bodies of these subsections vary by a factor 4. Compared with corresponding quantities for the skeleton, total mass, as well as total (137)Cs- and (40)K-activities of the whole vertebral column came to 14%, and approximately 38% for each (137)Cs and (40)K, respectively.

  18. Comparative cytogenetic mapping of Sox2 and Sox14 in cichlid fishes and inferences on the genomic organization of both genes in vertebrates

    PubMed Central

    Mazzuchelli, Juliana; Yang, Fengtang; Kocher, Thomas D.; Martins, Cesar

    2011-01-01

    To better understand the genomic organization and evolution of Sox genes in vertebrates, we cytogenetically mapped Sox2 and Sox14 genes in cichlid fishes and performed comparative analyses of their orthologs in several vertebrate species. The genomic regions neighbouring Sox2 and Sox14 have been conserved during vertebrate diversification. Although cichlids seem to have undergone high rates of genomic rearrangements, Sox2 and Sox14 are linked in the same chromosome in the Etroplinae Etroplus maculatus that represents the sister group of all remaining cichlids. However, this genes are located on different chromosomes in several species of the sister group Pseudocrenilabrinae. Similarly the ancestral synteny of Sox2 and Sox14 has been maintained in several vertebrates, but this synteny has been broken independently in all major groups as a consequence of karyotype rearrangements that took place during the vertebrate evolution. PMID:21691861

  19. Vertebral pathology in the afar australopithecines.

    PubMed

    Cook, D C; Buikstra, J E; DeRousseau, C J; Johanson, D C

    1983-01-01

    Ten vertebral elements from the AL-288 partial hominid skeleton and 11 elements from the AL-333 collection are described. The AL-288 column presents a marked kyphosis at the level of thoracic vertebrae 6 through 10, with pronounced new bone formation on the ventral surfaces of these vertebrae. These features, associated with narrowed disc space and minor osteophytosis, resemble Scheuermann disease in the human. Even though this diagnosis is consistent with a basically human, bipedal locomotor repertoire, the presence of Scheuermann disease suggests that lifting, climbing, or acrobatic activities may have been important in early hominids.

  20. Vertebrate gravity sensors as dynamic systems

    NASA Technical Reports Server (NTRS)

    Ross, M. D.

    1985-01-01

    This paper considers verterbrate gravity receptors as dynamic sensors. That is, it is hypothesized that gravity is a constant force to which an acceleration-sensing system would readily adapt. Premises are considered in light of the presence of kinocilia on hair cells of vertebrate gravity sensors; differences in loading of the sensors among species; and of possible reduction in loading by inclusion of much organic material in otoconia. Moreover, organic-inorganic interfaces may confer a piezoelectric property upon otoconia, which increase the sensitivity of the sensory system to small accelerations. Comparisons with man-made accelerometers are briefly taken up.

  1. Cervical Spine Fracture With Vertebral Artery Dissection.

    PubMed

    Halfpap, Joshua P; Cho, Aaron A; Rosenthal, Michael D

    2016-10-01

    A 51-year-old man presented to a direct-access physical therapy clinic with persistent neck pain for 5 days after a fall in shallow water while surfing. Based on "dangerous mechanism of injury" from the Canadian cervical spine rule as being a high risk factor, the physical therapist ordered radiographs of the cervical spine, which were suggestive of a more serious injury. Computed tomography suggested and magnetic resonance imaging confirmed vertebral artery dissection. J Orthop Sports Phys Ther 2016;46(10):929. doi:10.2519/jospt.2016.0416.

  2. Intracranial Vertebral Artery Dissections: Evolving Perspectives

    PubMed Central

    Ali, M.S.; Amenta, P.S.; Starke, R.M.; Jabbour, P.M.; Gonzalez, L.F.; Tjoumakaris, S.I.; Flanders, A.E.; Rosenwasser, R.H.; Dumont, A.S.

    2012-01-01

    Summary Intracranial vertebral artery dissection (VAD) represents the underlying etiology in a significant percentage of posterior circulation ischemic strokes and subarachnoid hemorrhages. These lesions are particularly challenging in their diagnosis, management, and in the prediction of long-term outcome. Advances in the understanding of underlying processes leading to dissection, as well as the evolution of modern imaging techniques are discussed. The data pertaining to medical management of intracranial VADs, with emphasis on anticoagulants and antiplatelet agents, is reviewed. Surgical intervention is discussed, including, the selection of operative candidates, open and endovascular procedures, and potential complications. The evolution of endovascular technology and techniques is highlighted. PMID:23217643

  3. Vertebrate Endoderm Development and Organ Formation

    PubMed Central

    Zorn, Aaron M.; Wells, James M.

    2010-01-01

    The endoderm germ layer contributes to the respiratory and gastrointestinal tracts, and all of their associated organs. Over the past decade, studies in vertebrate model organisms; including frog, fish, chick, and mouse; have greatly enhanced our understanding of the molecular basis of endoderm organ development. We review this progress with a focus on early stages of endoderm organogenesis including endoderm formation, gut tube morphogenesis and patterning, and organ specification. Lastly, we discuss how developmental mechanisms that regulate endoderm organogenesis are used to direct differentiation of embryonic stem cells into specific adult cell types, which function to alleviate disease symptoms in animal models. PMID:19575677

  4. Molecular evolution of color vision in vertebrates.

    PubMed

    Yokoyama, Shozo

    2002-10-30

    Visual systems of vertebrates exhibit a striking level of diversity, reflecting their adaptive responses to various color environments. The photosensitive molecules, visual pigments, can be synthesized in vitro and their absorption spectra can be determined. Comparing the amino acid sequences and absorption spectra of various visual pigments, we can identify amino acid changes that have modified the absorption spectra of visual pigments. These hypotheses can then be tested using the in vitro assay. This approach has been a powerful tool in elucidating not only the molecular bases of color vision, but the processes of adaptive evolution at the molecular level.

  5. [Comprehensive therapy of symptomatic vertebral haemangiomas].

    PubMed

    Hrabálek, L

    2010-04-01

    Vertebral haemangiomas (VH) are usually asymptomatic and are often found incidentally at spinal examination by imaging methods. Nevertheless, some haemangiomas can be clinically manifested by various degrees of axial pain and neurological deficit. The aim of this report is to show that this is a complex issue that requires a comprehensive approach to its treatment. The author reports on three patients with aggressive forms of cervical and lumbar VH treated by radiation therapy or vertebroplasty and hemilaminectomy with resection of the intraspinal thoratic component of a tumour. He discusses his findings in relation to the scarce data found on this topic in the literature.

  6. Vertebrate gravity sensors as dynamic systems

    NASA Technical Reports Server (NTRS)

    Ross, M. D.

    1985-01-01

    This paper considers verterbrate gravity receptors as dynamic sensors. That is, it is hypothesized that gravity is a constant force to which an acceleration-sensing system would readily adapt. Premises are considered in light of the presence of kinocilia on hair cells of vertebrate gravity sensors; differences in loading of the sensors among species; and of possible reduction in loading by inclusion of much organic material in otoconia. Moreover, organic-inorganic interfaces may confer a piezoelectric property upon otoconia, which increase the sensitivity of the sensory system to small accelerations. Comparisons with man-made accelerometers are briefly taken up.

  7. [Cloning of vertebrates: successes and problems].

    PubMed

    Koniukhov, B V

    1997-12-01

    Cloning of vertebrates, in particular, amphibians and mammals, is discussed. In the last decade, significant progress was made cloning mammals, while cloning of adult amphibians remained problematical. Low-traumatic methods of enucleation of recipient oocytes and transplantation of donor nuclei were worked out. In 1997, an adult sheep was cloned in Great Britain, thus demonstrating the possibility of cloning adult mammals. However, methods of cloning mammals need improvement because of the high lethality of reconstructed embryos (nuclear transplants). The use of in vitro cultured low-differentiated stem cells to obtain donor nuclei seems promising. Works on human cloning are not expedient in the near future because of technical and ethical aspects.

  8. A standard system to study vertebrate embryos.

    PubMed

    Werneburg, Ingmar

    2009-06-12

    Staged embryonic series are important as reference for different kinds of biological studies. I summarise problems that occur when using 'staging tables' of 'model organisms'. Investigations of developmental processes in a broad scope of taxa are becoming commonplace. Beginning in the 1990s, methods were developed to quantify and analyse developmental events in a phylogenetic framework. The algorithms associated with these methods are still under development, mainly due to difficulties of using non-independent characters. Nevertheless, the principle of comparing clearly defined newly occurring morphological features in development (events) in quantifying analyses was a key innovation for comparative embryonic research. Up to date no standard was set for how to define such events in a comparative approach. As a case study I compared the external development of 23 land vertebrate species with a focus on turtles, mainly based on reference staging tables. I excluded all the characters that are only identical for a particular species or general features that were only analysed in a few species. Based on these comparisons I defined 104 developmental characters that are common either for all vertebrates (61 characters), gnathostomes (26), tetrapods (3), amniotes (7), or only for sauropsids (7). Characters concern the neural tube, somite, ear, eye, limb, maxillary and mandibular process, pharyngeal arch, eyelid or carapace development. I present an illustrated guide listing all the defined events. This guide can be used for describing developmental series of any vertebrate species or for documenting specimen variability of a particular species. The guide incorporates drawings and photographs as well as consideration of species identifying developmental features such as colouration. The simple character-code of the guide is extendable to further characters pertaining to external and internal morphological, physiological, genetic or molecular development, and also for other

  9. A Standard System to Study Vertebrate Embryos

    PubMed Central

    Werneburg, Ingmar

    2009-01-01

    Staged embryonic series are important as reference for different kinds of biological studies. I summarise problems that occur when using ‘staging tables’ of ‘model organisms’. Investigations of developmental processes in a broad scope of taxa are becoming commonplace. Beginning in the 1990s, methods were developed to quantify and analyse developmental events in a phylogenetic framework. The algorithms associated with these methods are still under development, mainly due to difficulties of using non-independent characters. Nevertheless, the principle of comparing clearly defined newly occurring morphological features in development (events) in quantifying analyses was a key innovation for comparative embryonic research. Up to date no standard was set for how to define such events in a comparative approach. As a case study I compared the external development of 23 land vertebrate species with a focus on turtles, mainly based on reference staging tables. I excluded all the characters that are only identical for a particular species or general features that were only analysed in a few species. Based on these comparisons I defined 104 developmental characters that are common either for all vertebrates (61 characters), gnathostomes (26), tetrapods (3), amniotes (7), or only for sauropsids (7). Characters concern the neural tube, somite, ear, eye, limb, maxillary and mandibular process, pharyngeal arch, eyelid or carapace development. I present an illustrated guide listing all the defined events. This guide can be used for describing developmental series of any vertebrate species or for documenting specimen variability of a particular species. The guide incorporates drawings and photographs as well as consideration of species identifying developmental features such as colouration. The simple character-code of the guide is extendable to further characters pertaining to external and internal morphological, physiological, genetic or molecular development, and also

  10. Functional diversification of taste cells in vertebrates

    PubMed Central

    Matsumoto, Ichiro; Ohmoto, Makoto; Abe, Keiko

    2012-01-01

    Tastes are senses resulting from the activation of taste cells distributed in oral epithelia. Sweet, umami, bitter, sour, and salty tastes are called the five “basic” tastes, but why five, and why these five? In this review, we dissect the peripheral gustatory system in vertebrates from molecular and cellular perspectives. Recent behavioral and molecular genetic studies have revealed the nature of functional taste receptors and cells and show that different taste qualities are accounted for by the activation of different subsets of taste cells. Based on this concept, the diversity of basic tastes should be defined by the diversity of taste cells in taste buds, which varies among species. PMID:23085625

  11. Evaluation and Management of Vertebral Compression Fractures

    PubMed Central

    Alexandru, Daniela; So, William

    2012-01-01

    Compression fractures affect many individuals worldwide. An estimated 1.5 million vertebral compression fractures occur every year in the US. They are common in elderly populations, and 25% of postmenopausal women are affected by a compression fracture during their lifetime. Although these fractures rarely require hospital admission, they have the potential to cause significant disability and morbidity, often causing incapacitating back pain for many months. This review provides information on the pathogenesis and pathophysiology of compression fractures, as well as clinical manifestations and treatment options. Among the available treatment options, kyphoplasty and percutaneous vertebroplasty are two minimally invasive techniques to alleviate pain and correct the sagittal imbalance of the spine. PMID:23251117

  12. Quaternary vertebrates from Greenland: A review

    NASA Astrophysics Data System (ADS)

    Bennike, Ole

    Remains of fishes, birds and mammals are rarely reported from Quaternary deposits in Greenland. The oldest remains come from Late Pliocene and Early Pleistocene deposits and comprise Atlantic cod, hare, rabbit and ringed seal. Interglacial and interstadial deposits have yielded remains of cod, little auk, collared lemming, ringed seal, reindeer and bowhead whale. Early and Mid-Holocene finds include capelin, polar cod, red fish, sculpin, three-spined stickleback, Lapland longspur, Arctic hare, collared lemming, wolf, walrus, ringed seal, reindeer and bowhead whale. It is considered unlikely that vertebrates could survive in Greenland during the peak of the last glaciation, but many species had probably already immigrated in the Early Holocene.

  13. Growing models of vertebrate limb development.

    PubMed

    Towers, Matthew; Tickle, Cheryll

    2009-01-01

    The developing limb has been a very influential system for studying pattern formation in vertebrates. In the past, classical embryological models have explained how patterned structures are generated along the two principal axes of the limb: the proximodistal (shoulder to finger) and anteroposterior (thumb to little finger) axes. Over time, the genetic and molecular attributes of these patterning models have been discovered, while the role of growth in the patterning process has been only recently highlighted. In this review, we discuss these recent findings and propose how the various models of limb patterning can be reconciled.

  14. A hotspot of gene order rearrangement by tandem duplication and random loss in the vertebrate mitochondrial genome.

    PubMed

    San Mauro, Diego; Gower, David J; Zardoya, Rafael; Wilkinson, Mark

    2006-01-01

    Most reported examples of change in vertebrate mitochondrial (mt) gene order could be explained by a tandem duplication followed by random loss of redundant genes (tandem duplication-random loss [TDRL] model). Under this model of evolution, independent loss of genes arising from a single duplication in an ancestral species are predicted, and remnant pseudogenes expected, intermediate states that may remain in rearranged genomes. However, evidence for this is rare and largely scattered across vertebrate lineages. Here, we report new derived mt gene orders in the vertebrate "WANCY" region of four closely related caecilian amphibians. The novel arrangements found in this genomic region (one of them is convergent with the derived arrangement of marsupials), presence of pseudogenes, and positions of intergenic spacers fully satisfy predictions from the TDRL model. Our results, together with comparative data for the available vertebrate complete mt genomes, provide further evidence that the WANCY genomic region is a hotspot for gene order rearrangements and support the view that TDRL is the dominant mechanism of gene order rearrangement in vertebrate mt genomes. Convergent gene rearrangements are not unlikely in hotspots of gene order rearrangement by TDRL.

  15. Axial allometry in a neutrally buoyant environment: effects of the terrestrial-aquatic transition on vertebral scaling.

    PubMed

    Jones, K E; Pierce, S E

    2016-03-01

    Ecological diversification into new environments presents new mechanical challenges for locomotion. An extreme example of this is the transition from a terrestrial to an aquatic lifestyle. Here, we examine the implications of life in a neutrally buoyant environment on adaptations of the axial skeleton to evolutionary increases in body size. On land, mammals must use their thoracolumbar vertebral column for body support against gravity and thus exhibit increasing stabilization of the trunk as body size increases. Conversely, in water, the role of the axial skeleton in body support is reduced, and, in aquatic mammals, the vertebral column functions primarily in locomotion. Therefore, we hypothesize that the allometric stabilization associated with increasing body size in terrestrial mammals will be minimized in secondarily aquatic mammals. We test this by comparing the scaling exponent (slope) of vertebral measures from 57 terrestrial species (23 felids, 34 bovids) to 23 semi-aquatic species (pinnipeds), using phylogenetically corrected regressions. Terrestrial taxa meet predictions of allometric stabilization, with posterior vertebral column (lumbar region) shortening, increased vertebral height compared to width, and shorter, more disc-shaped centra. In contrast, pinniped vertebral proportions (e.g. length, width, height) scale with isometry, and in some cases, centra even become more spool-shaped with increasing size, suggesting increased flexibility. Our results demonstrate that evolution of a secondarily aquatic lifestyle has modified the mechanical constraints associated with evolutionary increases in body size, relative to terrestrial taxa.

  16. Two forms of adaptive immunity in vertebrates: similarities and differences.

    PubMed

    Kasahara, Masanori; Sutoh, Yoichi

    2014-01-01

    Unlike jawed vertebrates that use T-cell and B-cell receptors for antigen recognition, jawless vertebrates represented by lampreys and hagfish use variable lymphocyte receptors (VLRs) as antigen receptors. VLRs generate diversity comparable to that of gnathostome antigen receptors by assembling variable leucine-rich repeat modules. The discovery of VLR has revolutionized our understanding of how adaptive immunity emerged and highlighted the differences between the adaptive immune systems (AISs) of jawed and jawless vertebrates. However, emerging evidence also indicates that their AISs have much in common. Particularly striking is the conservation of lymphocyte lineages. The basic architecture of the AIS including the dichotomy of lymphocytes appears to have been established in a common ancestor of jawed and jawless vertebrates. We review here the current knowledge on the AIS of jawless vertebrates, emphasizing both the similarities to and differences from the AIS of jawed vertebrates. © 2014 Elsevier Inc. All rights reserved.

  17. A kind of specific osteolytic destruction of the vertebral bodies

    PubMed Central

    Peng, Baogan; Chen, Jinhong; Pang, Xiaodong; Hei, Yan

    2012-01-01

    This report describes two young patients with osteolytic destruction in two adjacent vertebral bodies along with the intervertebral disc, and reveals its possible mechanism. A lateral radiograph and CT scan displayed a giant osteolytic cavity in the L4 vertebral body. An MRI or CT scan with a two-dimensional reconstruction displayed the same changes in the L4 vertebral body and lower endplate erosion in the L3 vertebral body. A comprehensive preoperative evaluation did not identify a specific cause of vertebral destruction. Both patients underwent anterior lumbar fusion surgery. The lesions were removed for histological and immunohistochemical examination. Histopathological study of the destructed vertebral bodies in the two patients revealed the disruption or atrophy of bone trabeculae with infiltration of a large amount of B-lymphocytes and macrophages into the marrow cavities. Studies of its pathogenesis reveal that it is likely to be a B-lymphocyte-mediated local immune inflammatory reaction in the lumbar spine. PMID:22675148

  18. Reconstruction of the vertebrate ancestral genome reveals dynamic genome reorganization in early vertebrates.

    PubMed

    Nakatani, Yoichiro; Takeda, Hiroyuki; Kohara, Yuji; Morishita, Shinichi

    2007-09-01

    Although several vertebrate genomes have been sequenced, little is known about the genome evolution of early vertebrates and how large-scale genomic changes such as the two rounds of whole-genome duplications (2R WGD) affected evolutionary complexity and novelty in vertebrates. Reconstructing the ancestral vertebrate genome is highly nontrivial because of the difficulty in identifying traces originating from the 2R WGD. To resolve this problem, we developed a novel method capable of pinning down remains of the 2R WGD in the human and medaka fish genomes using invertebrate tunicate and sea urchin genes to define ohnologs, i.e., paralogs produced by the 2R WGD. We validated the reconstruction using the chicken genome, which was not considered in the reconstruction step, and observed that many ancestral proto-chromosomes were retained in the chicken genome and had one-to-one correspondence to chicken microchromosomes, thereby confirming the reconstructed ancestral genomes. Our reconstruction revealed a contrast between the slow karyotype evolution after the second WGD and the rapid, lineage-specific genome reorganizations that occurred in the ancestral lineages of major taxonomic groups such as teleost fishes, amphibians, reptiles, and marsupials.

  19. Two anatomic variations of the vertebral artery in four patients.

    PubMed

    Cheng, Meixiong; Xiaodong, Xie; Wang, Chaohua; You, Chao; Mao, Boyong; He, Min; Zhang, Changwei

    2009-01-01

    In this article, we present four cases of rare anomalous aortic arch and vertebral arteries and discuss the possible embryologic etiologies. These include two cases in which the right vertebral artery originated from the right common carotid artery associated with an aberrant right subclavian artery originating from the middle of the aortic arch and two cases in which the left vertebral artery had a double origin from the left subclavian artery and aortic arch.

  20. The characters of Palaeozoic jawed vertebrates

    PubMed Central

    Brazeau, Martin D; Friedman, Matt

    2014-01-01

    Newly discovered fossils from the Silurian and Devonian periods are beginning to challenge embedded perceptions about the origin and early diversification of jawed vertebrates (gnathostomes). Nevertheless, an explicit cladistic framework for the relationships of these fossils relative to the principal crown lineages of the jawed vertebrates (osteichthyans: bony fishes and tetrapods; chondrichthyans: sharks, batoids, and chimaeras) remains elusive. We critically review the systematics and character distributions of early gnathostomes and provide a clearly stated hierarchy of synapomorphies covering the jaw-bearing stem gnathostomes and osteichthyan and chondrichthyan stem groups. We show that character lists, designed to support the monophyly of putative groups, tend to overstate their strength and lack cladistic corroboration. By contrast, synapomorphic hierarchies are more open to refutation and must explicitly confront conflicting evidence. Our proposed synapomorphy scheme is used to evaluate the status of the problematic fossil groups Acanthodii and Placodermi, and suggest profitable avenues for future research. We interpret placoderms as a paraphyletic array of stem-group gnathostomes, and suggest what we regard as two equally plausible placements of acanthodians: exclusively on the chondrichthyan stem, or distributed on both the chondrichthyan and osteichthyan stems. PMID:25750460

  1. Recursive splicing in long vertebrate genes.

    PubMed

    Sibley, Christopher R; Emmett, Warren; Blazquez, Lorea; Faro, Ana; Haberman, Nejc; Briese, Michael; Trabzuni, Daniah; Ryten, Mina; Weale, Michael E; Hardy, John; Modic, Miha; Curk, Tomaž; Wilson, Stephen W; Plagnol, Vincent; Ule, Jernej

    2015-05-21

    It is generally believed that splicing removes introns as single units from precursor messenger RNA transcripts. However, some long Drosophila melanogaster introns contain a cryptic site, known as a recursive splice site (RS-site), that enables a multi-step process of intron removal termed recursive splicing. The extent to which recursive splicing occurs in other species and its mechanistic basis have not been examined. Here we identify highly conserved RS-sites in genes expressed in the mammalian brain that encode proteins functioning in neuronal development. Moreover, the RS-sites are found in some of the longest introns across vertebrates. We find that vertebrate recursive splicing requires initial definition of an 'RS-exon' that follows the RS-site. The RS-exon is then excluded from the dominant mRNA isoform owing to competition with a reconstituted 5' splice site formed at the RS-site after the first splicing step. Conversely, the RS-exon is included when preceded by cryptic promoters or exons that fail to reconstitute an efficient 5' splice site. Most RS-exons contain a premature stop codon such that their inclusion can decrease mRNA stability. Thus, by establishing a binary splicing switch, RS-sites demarcate different mRNA isoforms emerging from long genes by coupling cryptic elements with inclusion of RS-exons.

  2. Permo-Triassic vertebrate extinctions: A program

    NASA Technical Reports Server (NTRS)

    Olson, E. C.

    1988-01-01

    Since the time of the Authors' study on this subject, a great deal of new information has become available. Concepts of the nature of extinctions have changed materially. The Authors' conclusion that a catastrophic event was not responsible for the extinction of vertebrates has modified to the extent that hypotheses involving either the impact of a massive extra-terrestrial body or volcanism provide plausible but not currently fully testable hypotheses. Stated changes resulted in a rapid decrease in organic diversity, as the ratio of origins of taxa to extinctions shifted from strongly positive to negative, with momentary equilibrium being reached at about the Permo-Triassic boundary. The proximate causes of the changes in the terrestrial biota appear to lie in two primary factors: (1) strong climatic changes (global mean temperatures, temperature ranges, humidity) and (2) susceptibility of the dominant vertebrates (large dicynodonts) and the glossopteris flora to disruption of the equlibrium of the world ecosystem. The following proximate causes have been proposed: (1) rhythmic fluctuations in solar radiation, (2) tectonic events as Pangea assembled, altering land-ocean relationships, patterns of wind and water circulation and continental physiography, (3) volcanism, and (4) changes subsequent to impacts of one or more massive extra terrestrial objects, bodies or comets. These hypotheses are discussed.

  3. High-altitude adaptations in vertebrate hemoglobins.

    PubMed

    Weber, Roy E

    2007-09-30

    Vertebrates at high altitude are subjected to hypoxic conditions that challenge aerobic metabolism. O(2) transport from the respiratory surfaces to tissues requires matching between the O(2) loading and unloading tensions and the O(2)-affinity of blood, which is an integrated function of hemoglobin's intrinsic O(2)-affinity and its allosteric interaction with cellular effectors (organic phosphates, protons and chloride). Whereas short-term altitudinal adaptations predominantly involve adjustments in allosteric interactions, long-term, genetically-coded adaptations typically involve changes in the structure of the haemoglobin molecules. The latter commonly comprise substitutions of amino acid residues at the effector binding sites, the heme-protein contacts, or at intersubunit contacts that stabilize either the low-affinity ('Tense') or the high-affinity ('Relaxed') structures of the molecules. Molecular heterogeneity (multiple isoHbs with differentiated oxygenation properties) can further broaden the range of physico-chemical conditions where Hb functions under altitudinal hypoxia. This treatise reviews the molecular and cellular mechanisms that adapt haemoglobin-oxygen affinities in mammals, birds and ectothermic vertebrates at high altitude.

  4. Gene expression throughout a vertebrate's embryogenesis

    PubMed Central

    2011-01-01

    Background Describing the patterns of gene expression during embryonic development has broadened our understanding of the processes and patterns that define morphogenesis. Yet gene expression patterns have not been described throughout vertebrate embryogenesis. This study presents statistical analyses of gene expression during all 40 developmental stages in the teleost Fundulus heteroclitus using four biological replicates per stage. Results Patterns of gene expression for 7,000 genes appear to be important as they recapitulate developmental timing. Among the 45% of genes with significant expression differences between pairs of temporally adjacent stages, significant differences in gene expression vary from as few as five to more than 660. Five adjacent stages have disproportionately more significant changes in gene expression (> 200 genes) relative to other stages: four to eight and eight to sixteen cell stages, onset of circulation, pre and post-hatch, and during complete yolk absorption. The fewest differences among adjacent stages occur during gastrulation. Yet, at stage 16, (pre-mid-gastrulation) the largest number of genes has peak expression. This stage has an over representation of genes in oxidative respiration and protein expression (ribosomes, translational genes and proteases). Unexpectedly, among all ribosomal genes, both strong positive and negative correlations occur. Similar correlated patterns of expression occur among all significant genes. Conclusions These data provide statistical support for the temporal dynamics of developmental gene expression during all stages of vertebrate development. PMID:21356103

  5. Generation of Viable Plant-Vertebrate Chimeras

    PubMed Central

    Aedo, Geraldine; Araya, Francisco; Hopfner, Ursula; Fernández, Juan; Allende, Miguel L.; Egaña, José T.

    2015-01-01

    The extreme dependence on external oxygen supply observed in animals causes major clinical problems and several diseases are related to low oxygen tension in tissues. The vast majority of the animals do not produce oxygen but a few exceptions have shown that photosynthetic capacity is physiologically compatible with animal life. Such symbiotic photosynthetic relationships are restricted to a few aquatic invertebrates. In this work we aimed to explore if we could create a chimerical organism by incorporating photosynthetic eukaryotic cells into a vertebrate animal model. Here, the microalgae Chlamydomonas reinhardtii was injected into zebrafish eggs and the interaction and viability of both organisms were studied. Results show that microalgae were distributed into different tissues, forming a fish-alga chimera organism for a prolonged period of time. In addition, microscopic observation of injected algae, in vivo expression of their mRNA and re-growth of the algae ex vivo suggests that they survived to the developmental process, living for several days after injection. Moreover microalgae did not trigger a significant inflammatory response in the fish. This work provides additional evidence to support the possibility that photosynthetic vertebrates can be engineered. PMID:26126202

  6. Sensing and surviving hypoxia in vertebrates.

    PubMed

    Jonz, Michael G; Buck, Leslie T; Perry, Steve F; Schwerte, Thorsten; Zaccone, Giacomo

    2016-02-01

    Surviving hypoxia is one of the most critical challenges faced by vertebrates. Most species have adapted to changing levels of oxygen in their environment with specialized organs that sense hypoxia, while only few have been uniquely adapted to survive prolonged periods of anoxia. The goal of this review is to present the most recent research on oxygen sensing, adaptation to hypoxia, and mechanisms of anoxia tolerance in nonmammalian vertebrates. We discuss the respiratory structures in fish, including the skin, gills, and air-breathing organs, and recent evidence for chemosensory neuroepithelial cells (NECs) in these tissues that initiate reflex responses to hypoxia. The use of the zebrafish as a genetic and developmental model has allowed observation of the ontogenesis of respiratory and chemosensory systems, demonstration of a putative intracellular O2 sensor in chemoreceptors that may initiate transduction of the hypoxia signal, and investigation into the effects of extreme hypoxia on cardiorespiratory development. Other organisms, such as goldfish and freshwater turtles, display a high degree of anoxia tolerance, and these models are revealing important adaptations at the cellular level, such as the regulation of glutamatergic and GABAergic neurotransmission in defense of homeostasis in central neurons.

  7. A Membrane-Bound Vertebrate Globin

    PubMed Central

    Blank, Miriam; Wollberg, Jessica; Gerlach, Frank; Reimann, Katja; Roesner, Anja; Hankeln, Thomas; Fago, Angela; Weber, Roy E.; Burmester, Thorsten

    2011-01-01

    The family of vertebrate globins includes hemoglobin, myoglobin, and other O2-binding proteins of yet unclear functions. Among these, globin X is restricted to fish and amphibians. Zebrafish (Danio rerio) globin X is expressed at low levels in neurons of the central nervous system and appears to be associated with the sensory system. The protein harbors a unique N-terminal extension with putative N-myristoylation and S-palmitoylation sites, suggesting membrane-association. Intracellular localization and transport of globin X was studied in 3T3 cells employing green fluorescence protein fusion constructs. Both myristoylation and palmitoylation sites are required for correct targeting and membrane localization of globin X. To the best of our knowledge, this is the first time that a vertebrate globin has been identified as component of the cell membrane. Globin X has a hexacoordinate binding scheme and displays cooperative O2 binding with a variable affinity (P50∼1.3–12.5 torr), depending on buffer conditions. A respiratory function of globin X is unlikely, but analogous to some prokaryotic membrane-globins it may either protect the lipids in cell membrane from oxidation or may act as a redox-sensing or signaling protein. PMID:21949889

  8. Early jawless vertebrates and cyclostome origins.

    PubMed

    Janvier, Philippe

    2008-10-01

    Undoubted fossil lampreys are recorded since the Late Devonian (358 Ma), and probable fossil hagfishes since the Late Carboniferous (300 Ma), but molecular clock data suggest a much earlier divergence times for the two groups. In the early 20(th) century, hagfishes and lampreys were generally thought to have diverged much later from unknown ancestral cyclostomes, in turn derived through 'degeneracy' from some Paleozoic armored jawless vertebrates, or 'ostracoderms.' However, current vertebrate phylogenies suggest that most, if not all, 'ostracoderms' are in fact jawless stem gnathostomes, which retain certain features that were once regarded as unique to the cyclostomes, such as gill pouches or lack of horizontal semicircular canal. The dorsal, median, nasohypophysial complex of osteostracans has been regarded as identical and homologous to that of lampreys, but recent investigation (notably on the galeaspid braincase) now suggests that this resemblance is in fact a convergence. The anatomy and physiology of lampreys and hagfishes are so different that it is difficult to reconstruct an ancestral morphotype of the cyclostomes, assuming that they are a clade, and there is no clear evidence of any fossil taxon that is neither a fossil hagfish nor a fossil lamprey, but would be more closely related to the cyclostomes than to the gnathostomes. A possible exception is the Silurian-Devonian euphaneropids (or 'naked anaspids').

  9. The evolution of vertebrate opioid receptors

    PubMed Central

    Stevens, Craig W.

    2011-01-01

    The proteins that mediate the analgesic and other effects of opioid drugs and endogenous opioid peptides are known as opioid receptors. Opioid receptors consist of a family of four closely-related proteins belonging to the large superfamily of G-protein coupled receptors. The three types of opioid receptors shown unequivocally to mediate analgesia in animal models are the mu (MOR), delta (DOR), and kappa (KOR) opioid receptor proteins. The role of the fourth member of the opioid receptor family, the nociceptin or orphanin FQ receptor (ORL), is not as clear as hyperalgesia, analgesia, and no effect was reported after administration of ORL agonists. There are now cDNA sequences for all four types of opioid receptors that are expressed in the brain of six species from three different classes of vertebrates. This review presents a comparative analysis of vertebrate opioid receptors using bioinformatics and data from recent human genome studies. Results indicate that opioid receptors arose by gene duplication, that there is a vector of opioid receptor divergence, and that MOR shows evidence of rapid evolution. PMID:19273128

  10. Identifying Synonymous Regulatory Elements in Vertebrate Genomes

    SciTech Connect

    Ovcharenko, I; Nobrega, M A

    2005-02-07

    Synonymous gene regulation, defined as driving shared temporal and/or spatial expression of groups of genes, is likely predicated on genomic elements that contain similar modules of certain transcription factor binding sites (TFBS). We have developed a method to scan vertebrate genomes for evolutionary conserved modules of TFBS in a predefined configuration, and created a tool, named SynoR that identify synonymous regulatory elements (SREs) in vertebrate genomes. SynoR performs de novo identification of SREs utilizing known patterns of TFBS in active regulatory elements (REs) as seeds for genome scans. Layers of multiple-species conservation allow the use of differential phylogenetic sequence conservation filters in the search of SREs and the results are displayed as to provide an extensive annotation of genes containing detected REs. Gene Ontology categories are utilized to further functionally classify the identified genes, and integrated GNF Expression Atlas 2 data allow the cataloging of tissue-specificities of the predicted SREs. We illustrate how this new tool can be used to establish a linkage between human diseases and noncoding genomic content. SynoR is publicly available at http://synor.dcode.org.

  11. Vertebrate helentrons and other novel Helitrons.

    PubMed

    Poulter, Russell T M; Goodwin, Timothy J D; Butler, Margaret I

    2003-08-14

    Helitrons, a novel class of eukaryote mobile genetic elements, are distinguished from other transposable elements by encoding a 'rolling circle' replication (RCR) protein (Rep) and a helicase. Helitrons have recently been described from Arabidopsis, rice and the nematode Caenorhabditis. We now report the discovery of Helitron-like elements in vertebrates, specifically in the genomes of the fish Danio rerio and Sphoeroides nephelus. We also describe Helitrons from the white rot fungus Phanerochaete chrysosporium and from the Anopheles genome. Many of the fish Helitrons have an uncorrupted open reading frame encoding both the RCR Rep protein and a helicase. These fish elements are of particular interest because they also encode, within the single open reading frame, an apurinic-apyrimidinic (AP) endonuclease most closely related to those of certain non-long terminal repeat retrotransposons. As they invariably carry an endonuclease and also form a very distinct clade, we have named these vertebrate elements 'helentrons'. It is likely that these helentrons are still active.

  12. TRPM7 regulates gastrulation during vertebrate embryogenesis

    PubMed Central

    Liu, Wei; Su, Li-Ting; Khadka, Deepak K.; Mezzacappa, Courtney; Komiya, Yuko; Sato, Akira; Habas, Raymond; Runnels, Loren W.

    2010-01-01

    During gastrulation, cells in the dorsal marginal zone polarize, elongate, align and intercalate to establish the physical body axis of the developing embryo. Here we demonstrate that the bifunctional channel-kinase TRPM7 is specifically required for vertebrate gastrulation. TRPM7 is temporally expressed maternally and throughout development, and is spatially enriched in tissues undergoing convergent extension during gastrulation. Functional studies reveal that TRPM7’s ion channel, but not its kinase, specifically affects cell polarity and convergent extension movements during gastrulation, independent of mesodermal specification. During gastrulation, the non-canonical Wnt pathway via Dishevelled (Dvl) orchestrates the activities of the GTPases Rho and Rac to control convergent extension movements. We find that TRPM7 functions synergistically with non-canonical Wnt signaling to regulate Rac activity. The phenotype caused by depletion of the Ca2+- and Mg2+-permeant TRPM7 is suppressed by expression of a dominant negative form of Rac, as well as by Mg2+ supplementation or by expression of the Mg2+ transporter SLC41A2. Together, these studies demonstrate an essential role for the ion channel TRPM7 and Mg2+ in Rac-dependent polarized cell movements during vertebrate gastrulation. PMID:21145885

  13. The cat vertebral column: stance configuration and range of motion

    NASA Technical Reports Server (NTRS)

    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

  14. The cat vertebral column: stance configuration and range of motion

    NASA Technical Reports Server (NTRS)

    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

  15. Vertebral bone marrow fat associated with lower trabecular BMD and prevalent vertebral fracture in older adults.

    PubMed

    Schwartz, Ann V; Sigurdsson, Sigurdur; Hue, Trisha F; Lang, Thomas F; Harris, Tamara B; Rosen, Clifford J; Vittinghoff, Eric; Siggeirsdottir, Kristin; Sigurdsson, Gunnar; Oskarsdottir, Diana; Shet, Keerthi; Palermo, Lisa; Gudnason, Vilmundur; Li, Xiaojuan

    2013-06-01

    Bone marrow fat (BMF) and bone mineral density (BMD) by dual x-ray energy absorptiometry (DXA) are negatively correlated. However, little is known about the association of BMF with fracture or with separate trabecular and cortical bone compartments. Our objective was to assess the relationships between vertebral BMF, BMD by quantitative computed tomography, and fracture in older adults. We conducted a cross-sectional study in the Age Gene/Environment Susceptibility-Reykjavik cohort. Outcomes measures included vertebral BMF (L1-L4) measured with magnetic resonance spectroscopy, quantitative computed tomography and DXA scans of the hip and spine, and DXA vertebral fracture assessments. Previous clinical fracture was determined from medical records. In 257 participants without recent bone-active medication use, mean age was 79 (SD 3.1) years. Mean BMF was 53.5% ± 8.1% in men and 55.0% ± 8.4% in women. Those with prevalent vertebral fracture (21 men, 32 women) had higher mean BMF in models adjusted for BMD. In separate models by sex, the difference was statistically significant only in men (57.3% vs 52.8%, P = 0.02). BMF was associated with lower trabecular volumetric BMD (vBMD) at the spine (-10.5% difference for each 1 SD increase in BMF, P < 0.01), total hip, and femoral neck, but not with cortical vBMD, in women. In men, BMF was marginally associated with trabecular spine vBMD (-6.1%, P = 0.05). Total hip and spine areal BMD (aBMD) were negatively correlated with BMF in women only. Higher marrow fat correlated with lower trabecular, but not cortical, BMD in older women but not men. Higher marrow fat was associated with prevalent vertebral fracture in men, even after adjustment for BMD.

  16. From cyst to tubule: innovations in vertebrate spermatogenesis.

    PubMed

    Yoshida, Shosei

    2016-01-01

    Although vertebrates share many common traits, their germline development and function exhibit significant divergence. In particular, this article focuses on their spermatogenesis. The fundamental elements that constitute vertebrate spermatogenesis and the evolutionary changes that occurred upon transition from water to land will be discussed. The life-long continuity of spermatogenesis is supported by the function of stem cells. Series of mitotic and meiotic germ cell divisions are 'incomplete' due to incomplete cytokinesis, forming syncytia interconnected via intercellular bridges (ICBs). Throughout this process, germ cells are supported by appropriate microenvironments established primarily by somatic Sertoli cells. In anamniotes (fish and amphibians) spermatogenesis progresses in cysts, in which developing germ cell syncytia are individually encapsulated by Sertoli cells. Accordingly, Sertoli cells undergo turnover with germ cells that they nourish. This mode of cystic spermatogenesis is also observed in nonvertebrates as insects. In amniotes (reptiles, birds, and mammals), however, Sertoli cells do not turn over but comprise a persistent structure of seminiferous tubules. Sertoli cells nourish different stages of germ cells simultaneously in distinct regions of their surface. This function of Sertoli cells is spatiotemporally orchestrated, and the seminiferous epithelial cycle and spermatogenic wave make the seminiferous tubules a high-throughput factory for sperm production. Furthermore, contrary to the organized differentiating cells, undifferentiated spermatogonia that comprise the stem cell compartment exhibit active motion over the basal layer of seminiferous tubules and the frequent breakdown of ICBs. Thus, amniote seminiferous tubules represent a typical facultative (or open) niche environment without a stem cell tethering anatomically defined niche. WIREs Dev Biol 2016, 5:119-131. doi: 10.1002/wdev.204 For further resources related to this article

  17. Mitochondrial heteroplasmy in vertebrates using ChIP-sequencing data.

    PubMed

    Rensch, Thomas; Villar, Diego; Horvath, Julie; Odom, Duncan T; Flicek, Paul

    2016-06-27

    Mitochondrial heteroplasmy, the presence of more than one mitochondrial DNA (mtDNA) variant in a cell or individual, is not as uncommon as previously thought. It is mostly due to the high mutation rate of the mtDNA and limited repair mechanisms present in the mitochondrion. Motivated by mitochondrial diseases, much focus has been placed into studying this phenomenon in human samples and in medical contexts. To place these results in an evolutionary context and to explore general principles of heteroplasmy, we describe an integrated cross-species evaluation of heteroplasmy in mammals that exploits previously reported NGS data. Focusing on ChIP-seq experiments, we developed a novel approach to detect heteroplasmy from the concomitant mitochondrial DNA fraction sequenced in these experiments. We first demonstrate that the sequencing coverage of mtDNA in ChIP-seq experiments is sufficient for heteroplasmy detection. We then describe a novel detection method for accurate detection of heteroplasmies, which also accounts for the error rate of NGS technology. Applying this method to 79 individuals from 16 species resulted in 107 heteroplasmic positions present in a total of 45 individuals. Further analysis revealed that the majority of detected heteroplasmies occur in intergenic regions. In addition to documenting the prevalence of mtDNA in ChIP-seq data, the results of our mitochondrial heteroplasmy detection method suggest that mitochondrial heteroplasmies identified across vertebrates share similar characteristics as found for human heteroplasmies. Although largely consistent with previous studies in individual vertebrates, our integrated cross-species analysis provides valuable insights into the evolutionary dynamics of mitochondrial heteroplasmy.

  18. Functional significance of the taper of vertebrate cone photoreceptors

    PubMed Central

    Hárosi, Ferenc I.

    2012-01-01

    Vertebrate photoreceptors are commonly distinguished based on the shape of their outer segments: those of cones taper, whereas the ones from rods do not. The functional advantages of cone taper, a common occurrence in vertebrate retinas, remain elusive. In this study, we investigate this topic using theoretical analyses aimed at revealing structure–function relationships in photoreceptors. Geometrical optics combined with spectrophotometric and morphological data are used to support the analyses and to test predictions. Three functions are considered for correlations between taper and functionality. The first function proposes that outer segment taper serves to compensate for self-screening of the visual pigment contained within. The second function links outer segment taper to compensation for a signal-to-noise ratio decline along the longitudinal dimension. Both functions are supported by the data: real cones taper more than required for these compensatory roles. The third function relates outer segment taper to the optical properties of the inner compartment whereby the primary determinant is the inner segment’s ability to concentrate light via its ellipsoid. In support of this idea, the rod/cone ratios of primarily diurnal animals are predicted based on a principle of equal light flux gathering between photoreceptors. In addition, ellipsoid concentration factor, a measure of ellipsoid ability to concentrate light onto the outer segment, correlates positively with outer segment taper expressed as a ratio of characteristic lengths, where critical taper is the yardstick. Depending on a light-funneling property and the presence of focusing organelles such as oil droplets, cone outer segments can be reduced in size to various degrees. We conclude that outer segment taper is but one component of a miniaturization process that reduces metabolic costs while improving signal detection. Compromise solutions in the various retinas and retinal regions occur between

  19. Placoderms (Armored Fish): Dominant Vertebrates of the Devonian Period

    NASA Astrophysics Data System (ADS)

    Young, Gavin C.

    2010-05-01

    Placoderms, the most diverse group of Devonian fishes, were globally distributed in all habitable freshwater and marine environments, like teleost fishes in the modern fauna. Their known evolutionary history (Early Silurian-Late Devonian) spanned at least 70 million years. Known diversity (335 genera) will increase when diverse assemblages from new areas are described. Placoderms first occur in the Early Silurian of China, but their diversity remained low until their main evolutionary radiation in the Early Devonian, after which they became the dominant vertebrates of Devonian seas. Most current placoderm data are derived from the second half of the group's evolutionary history, and recent claims that they form a paraphyletic group are based on highly derived Late Devonian forms; 16 shared derived characters are proposed here to support placoderm monophyly. Interrelationships of seven placoderm orders are unresolved because Silurian forms from China are still poorly known. The relationship of placoderms to the two major extant groups of jawed fishes—osteichthyans (bony fishes) and chondrichthyans (cartilaginous sharks, rays, and chimaeras)—remains uncertain, but the detailed preservation of placoderm internal braincase structures provides insights into the ancestral gnathostome (jawed vertebrate) condition. Placoderms provide the most complex morphological and biogeographic data set for the Middle Paleozoic; marked discrepancies in stratigraphic occurrence between different continental regions indicate strongly endemic faunas that were probably constrained by marine barriers until changes in paleogeography permitted range enlargement into new areas. Placoderm distributions in time and space indicate major faunal interchange between Gondwana and Laurussia near the Frasnian-Famennian boundary; closure of the Devonian equatorial ocean is a possible explanation.

  20. Vertebral microanatomy in squamates: structure, growth and ecological correlates.

    PubMed

    Houssaye, Alexandra; Mazurier, Arnaud; Herrel, Anthony; Volpato, Virginie; Tafforeau, Paul; Boistel, Renaud; De Buffrénil, Vivian

    2010-12-01

    The histological study of vertebrae in extant squamates shows that the internal vertebral structure in this group differs from that of other tetrapods. Squamate vertebrae are lightly built and basically composed of two roughly concentric osseous tubes--one surrounding the neural canal and the other constituting the peripheral cortex of the vertebra--connected by few thin trabeculae. This structure, which characteristically evokes that of a tubular bone, results from a peculiar remodelling process characterised by an imbalance between local bone resorption and redeposition; in both periosteal and endosteo-endochondral territories, bone is extensively resorbed but not reconstructed in the same proportion by secondary deposits. This process is particularly intense in the deep region of the centrum, where originally compact cortices are made cancellous, and where the endochondral spongiosa is very loose. This remodelling process starts at an early stage of development and remains active throughout subsequent growth. The growth of squamate centra is also strongly asymmetrical, with the posterior (condylar) part growing much faster than the anterior (cotylar) part. Preliminary analyses testing for associations between vertebral structure and habitat use suggest that vertebrae of fossorial taxa are denser than those of terrestrial taxa, those in aquatic taxa being of intermediate density. However, phylogenetically informed analyses do not corroborate these findings, thus suggesting a strong phylogenetic signal in the data. As our analyses demonstrate that vertebrae in snakes are generally denser than those of lizards sensu stricto, this may drive the presence of a phylogenetic signal in the data. More comprehensive sampling of fossorial and aquatic lizards is clearly needed to more rigorously evaluate these patterns. © 2010 The Authors. Journal of Anatomy © 2010 Anatomical Society of Great Britain and Ireland.

  1. Vertebral microanatomy in squamates: structure, growth and ecological correlates

    PubMed Central

    Houssaye, Alexandra; Mazurier, Arnaud; Herrel, Anthony; Volpato, Virginie; Tafforeau, Paul; Boistel, Renaud; de Buffrénil, Vivian

    2010-01-01

    The histological study of vertebrae in extant squamates shows that the internal vertebral structure in this group differs from that of other tetrapods. Squamate vertebrae are lightly built and basically composed of two roughly concentric osseous tubes – one surrounding the neural canal and the other constituting the peripheral cortex of the vertebra – connected by few thin trabeculae. This structure, which characteristically evokes that of a tubular bone, results from a peculiar remodelling process characterised by an imbalance between local bone resorption and redeposition; in both periosteal and endosteo-endochondral territories, bone is extensively resorbed but not reconstructed in the same proportion by secondary deposits. This process is particularly intense in the deep region of the centrum, where originally compact cortices are made cancellous, and where the endochondral spongiosa is very loose. This remodelling process starts at an early stage of development and remains active throughout subsequent growth. The growth of squamate centra is also strongly asymmetrical, with the posterior (condylar) part growing much faster than the anterior (cotylar) part. Preliminary analyses testing for associations between vertebral structure and habitat use suggest that vertebrae of fossorial taxa are denser than those of terrestrial taxa, those in aquatic taxa being of intermediate density. However, phylogenetically informed analyses do not corroborate these findings, thus suggesting a strong phylogenetic signal in the data. As our analyses demonstrate that vertebrae in snakes are generally denser than those of lizards sensu stricto, this may drive the presence of a phylogenetic signal in the data. More comprehensive sampling of fossorial and aquatic lizards is clearly needed to more rigorously evaluate these patterns. PMID:21039477

  2. Vascular Plant and Vertebrate Inventory of Coronado National Memorial

    USGS Publications Warehouse

    Schmidt, Cecilia A.; Powell, Brian F.; Swann, Don E.; Halvorson, William L.

    2007-01-01

    We conducted inventories for amphibians and reptiles, birds, and mammals; and summarized past inventories for vascular plants at Coronado National Memorial (NM) in Arizona. We used our data as well as data from previous research to compile species lists for the memorial, assess inventory completeness, and make suggestions on future monitoring efforts. There have been 940 species of plants and vertebrates recorded at Coronado NM (Table 1), of which 46 (5%) are non-native. The species richness of the memorial is one of the highest in the Sonoran Desert Network of park units, third only to park units that are two and one-half (Chiricahua National Monument), 19 (Saguaro National Park) and 70 (Organ Pipe Cactus National Monument) times larger in area. The high species diversities are due to the large elevational gradient, overlap of bigeographical regions, wide range of geology and soils, and diverse vegetation communities present at the memorial. Changes in species composition have occurred at the memorial over the last 20 years in all major taxonomic groups. These changes are likely due to increases in grassy plant species (both native and non-native) at the lower elevations of the memorial. We suspect that grassy plant cover has increased because of changes in grazing intensity, introduction of some non-native species, and a recent fire. All recent vertebrate inventories have yielded grassland obligate species not previously recorded at the memorial. Based on the review of past studies, we believe the inventory for most taxa, except bats, is nearly complete, though some rare or elusive species will likely be added with additional survey effort.

  3. Insight into the primordial MHC from studies in ectothermic vertebrates.

    PubMed

    Flajnik, M F; Ohta, Y; Namikawa-Yamada, C; Nonaka, M

    1999-02-01

    MHC classical class I and class II genes have been identified in representative species from all major jawed vertebrate taxa, the oldest group being the cartilaginous fish, whereas no class I/II genes of any type have been detected in animals from older taxa. Among ectothermic vertebrate classes, studies of MHC architecture have been done in cartilaginous fish (sharks), bony fish (several teleost species), and amphibians (the frog Xenopus). The Xenopus MHC contains class I, class II, and class III genes, demonstrating that all of these genes were linked in the ancestor of the tetrapods, but the gene order is not the same as that in mouse/man. Studies of polyploid Xenopus suggest that MHC genes can be differentially silenced when multiple copies are present; i.e. MHC 'subregions' can be silenced. Surprisingly, in all teleosts examined to date class I and class II genes are not linked. Likewise, class III genes like the complement genes factor B (Bf) and C4 are scattered throughout the genome of teleosts. However, the presumed classical class I genes are closely linked to the 'immune' proteasome genes, LMP2 and LMP7, and to the peptide-transporter genes (TAP), implying that a true 'class I region' exists in this group. A similar type of linkage group is found in chickens and perhaps Xenopus, and thus it may reveal the ancestral organization of class I-associated genes. In cartilaginous fish, classical and non-classical class I genes have been isolated from three shark species, and class II A and B chain genes from nurse sharks. Studies of MHC linkage in sharks are being carried out to provide further understanding of the putative primordial organization of MHC Segregation studies in one shark family point to linkage of classical class I and class II genes, suggesting that the non-linkage of these genes in teleosts is a derived characteristic.

  4. The use of wild vertebrates in contemporary Spanish ethnoveterinary medicine.

    PubMed

    González, José A; Amich, Francisco; Postigo-Mota, Salvador; Vallejo, José Ramón

    2016-09-15

    This review documents the wide and varied repertoire of traditional practices based on the use of wild vertebrates in Spanish ethnoveterinary medicine (EVM) from the early 20th century to the present. Empirical practices, both ritual and magical, are recorded, and these EVM data are compared with those of other countries in the Mediterranean Region and Latin America. The data collected here could form a scientific foundation for future inventories of traditional knowledge and help in the discovery of new drugs for livestock. A qualitative systematic review of international and national databases in the fields of ethnobiology, ethnoveterinary medicine, folklore and ethnography was made. Information was obtained from more than 60 documentary sources. We recorded the use of 30 wild vertebrates and a total of 84 empirical remedies based on the use of a single species. The two most relevant zoological groups are reptiles and mammals. A wide diversity of body parts or products have been and are used. The meat and skin of snakes are the animal products most commonly used. These zootherapeutic resources have been and are used to treat or prevent ca. 50 animal diseases or conditions, in particular digestive and reproductive ailments, together with some infectious diseases. Sheep, cattle and equines form the group of domestic animals in which the greatest number of useful species are employed. In addition, many remedies and practices of the magical type are documented. In comparison with other culturally related areas, this is a rich heritage. Contemporary Spanish EVM practices amass a great richness of wild animal-based remedies. A diversity of animal parts or products have been used, offering a cultural heritage that could be a fundamental step in the discovery of new and low-cost drugs for treating livestock and alternative materials for pharmaceutical purposes. This overview contributes to the inventory of some uses and rituals seriously threatened by the progressive

  5. Facts and fancies about early fossil chordates and vertebrates.

    PubMed

    Janvier, Philippe

    2015-04-23

    The interrelationships between major living vertebrate, and even chordate, groups are now reasonably well resolved thanks to a large amount of generally congruent data derived from molecular sequences, anatomy and physiology. But fossils provide unexpected combinations of characters that help us to understand how the anatomy of modern groups was progressively shaped over millions of years. The dawn of vertebrates is documented by fossils that are preserved as either soft-tissue imprints, or minute skeletal fragments, and it is sometimes difficult for palaeontologists to tell which of them are reliable vertebrate remains and which merely reflect our idea of an ancestral vertebrate.

  6. Candidal Vertebral Osteomyelitis in the Midst of Renal Disorders

    PubMed Central

    Kumar, Anil; Rao, Srivatsa Nagaraja; Kumar, Krishna; Karim, Shamsul

    2016-01-01

    Vertebral osteomyelitis also known as discitis/pyogenic spondylitis refers to inflammation of the vertebral disc space. It is commonly seen in men and adults more than 50 years of age. Fungal osteomyelitis is a rare scenario compared to its bacterial counterpart. Spinal epidural abscess is a dangerous complication associated with vertebral osteomyelitis. Here, we report two cases of vertebral osteomyelitis caused by Candida tropicalis in patients with renal disorders (stage 5 chronic kidney disease and nephropathy). One of the case discussed here presented with spinal epidural abscess. Both the patients were started on antifungal therapy. One patient responded to treatment while the other was lost to follow up. PMID:27190806

  7. Vertebral artery dissection related to basilar impression: case report.

    PubMed

    Dickinson, L D; Tuite, G F; Colon, G P; Papadopoulos, S M

    1995-04-01

    A 50-year-old man with myelopathy secondary to basilar impression developed bilateral vertebral artery dissection after undergoing treatment with 8 pounds of cervical traction. The vertebral artery dissection resulted in vertebrobasilar insufficiency and posterior circulation stroke. In this report, the current management philosophies in the treatment of basilar impression are discussed, and the pertinent neurovascular anatomy is illustrated. This report suggests that vertebral artery injury may result from attempted reduction of severe basilar impression. Regardless of the cause of cranial settling, the risk of vertebral artery injury with cervical traction should be considered in patients with severe basilar impression.

  8. Gravity, blood circulation, and the adaptation of form and function in lower vertebrates.

    PubMed

    Lillywhite, H B

    Gravitational force influences musculoskeletal systems, fluid distribution, and hydrodynamics of the circulation, especially in larger terrestrial vertebrates. The disturbance to hydrodynamics and distribution of body fluids relates largely to the effects of hydrostatic pressure gradients acting in vertical blood columns. These, in turn, are linked to the evolution of adaptive countermeasures involving modifications of structure and function. Comparative studies of snakes suggest there are four generalizations concerning adaptive countermeasures to gravity stress that seem relevant to lower vertebrates generally. First, increasing levels of regulated arterial blood pressure are expected to evolve with some relation to gravitational stresses incurred by the effects of height and posture on vertical blood columns above the heart. Second, aspects of gross anatomical organization are expected to evolve in relation to gravitational influence incurred by habitat and behavior. Third, natural selection coupled to gravitational stresses has favored morphological features that reduce the compliance of perivascular tissues and provide an anatomical "antigravity suit." Fourth, natural selection has produced gradients or regional differences of vascular characteristics in tall or elongated vertebrates that are active in high gravity stress environments. Consideration or awareness of these principles should be incorporated into interpretations of structure and function in lower vertebrates.

  9. Evolutionary study of vertebrate and invertebrate members of the dystrophin and utrophin gene family

    SciTech Connect

    Roberts, R.G.; Nicholson, L.; Bobrow, M.

    1994-09-01

    Vertebrates express two members of the dystrophin gene family. The prototype, dystrophin, is expressed in muscle and neural tissue, and is defective in the human disorders Duchenne and Becker muscular dystrophy (DMD, BMD). The dystrophin homologue utrophin is more generally expressed but has not yet been associated with a genetic disorder. The function of neither protein is clear. A comparison of human utrophin with the known dystrophins (human, mouse, chicken, Torpedo) suggests that dystrophin and utrophin diverged before the vertebrate radiation. We have used reverse-transcript PCR (RT-PCR) directed by degenerate primers to characterize dystrophin and utrophin transcripts from a range of vertebrate and invertebrate animals. Our results suggest that the duplication leading to distinct dystrophin and utrophin genes occurred close to the point of divergence of urochordates from the cephalochordate-vertebrate lineage. This divergence may have occurred to fulfill a novel role which arose at this point, or may reflect a need for separate regulation of the neuromuscular and other functions of the ancient dystrophin. Our data include sequences of the first non-human utrophins to be characterized, and show these to be substantially more divergent than their cognate dystrophins. In addition, our results provide a large body of information regarding the tolerance of amino acid positions in the cysteine-rich and C-terminal domains to substitution. This will aid the interpretations of DMD and BMD missense mutations in these regions.

  10. Vertebral column deformities in white-beaked dolphins from the eastern North Atlantic.

    PubMed

    Bertulli, Chiara G; Galatius, Anders; Kinze, Carl C; Rasmussen, Marianne H; Deaville, Rob; Jepson, Paul; Vedder, Elisabeth J; Sánchez Contreras, Guillermo J; Sabin, Richard C; Watson, Alastair

    2015-09-17

    Five white-beaked dolphins Lagenorhynchus albirostris with outwardly vertebral kyphosis, kyphoscoliosis or lordosis were identified during a photo-identification survey of over 400 individuals (2002-2013) in Faxaflói and Skjálfandi Bays, Iceland. In addition, 3 stranding reports from Denmark, The Netherlands and the UK were analysed, providing both external observation and post mortem details of axial deviations of the vertebral column in this species. Two of the free-ranging cases and 2 of the stranded specimens appeared to have an acquired disease, either as a direct result of trauma, or indirectly from trauma/wound and subsequent infection and bony proliferation, although we were unable to specifically identify the causes. Our data represent a starting point to understand vertebral column deformations and their implications in white-beaked dolphins from the eastern North Atlantic. We recommend for future necropsy cases to conduct macro- and microscopic evaluation of muscle from both sides of the deformed region, in order to assess chronic or acute conditions related to the vertebral deformations and cause of death.

  11. Nervous systems and scenarios for the invertebrate-to-vertebrate transition.

    PubMed

    Holland, Nicholas D

    2016-01-05

    Older evolutionary scenarios for the origin of vertebrates often gave nervous systems top billing in accordance with the notion that a big-brained Homo sapiens crowned a tree of life shaped mainly by progressive evolution. Now, however, tree thinking positions all extant organisms equidistant from the tree's root, and molecular phylogenies indicate that regressive evolution is more common than previously suspected. Even so, contemporary theories of vertebrate origin still focus on the nervous system because of its functional importance, its richness in characters for comparative biology, and its central position in the two currently prominent scenarios for the invertebrate-to-vertebrate transition, which grew out of the markedly neurocentric annelid and enteropneust theories of the nineteenth century. Both these scenarios compare phyla with diverse overall body plans. This diversity, exacerbated by the scarcity of relevant fossil data, makes it challenging to establish plausible homologies between component parts (e.g. nervous system regions). In addition, our current understanding of the relation between genotype and phenotype is too preliminary to permit us to convert gene network data into structural features in any simple way. These issues are discussed here with special reference to the evolution of nervous systems during proposed transitions from invertebrates to vertebrates. © 2015 The Author(s).

  12. Ontogenetic cell death and phagocytosis in the visual system of vertebrates.

    PubMed

    Francisco-Morcillo, Javier; Bejarano-Escobar, Ruth; Rodríguez-León, Joaquín; Navascués, Julio; Martín-Partido, Gervasio

    2014-10-01

    Programmed cell death (PCD), together with cell proliferation, cell migration, and cell differentiation, is an essential process during development of the vertebrate nervous system. The visual system has been an excellent model on which to investigate the mechanisms involved in ontogenetic cell death. Several phases of PCD have been reported to occur during visual system ontogeny. During these phases, comparative analyses demonstrate that dying cells show similar but not identical spatiotemporally restricted patterns in different vertebrates. Additionally, the chronotopographical coincidence of PCD with the entry of specialized phagocytes in some regions of the developing vertebrate visual system suggests that factors released from degenerating cells are involved in the cell migration of macrophages and microglial cells. Contradicting this hypothesis however, in many cases the cell corpses generated during degeneration are rapidly phagocytosed by neighboring cells, such as neuroepithelial cells or Müller cells. In this review, we describe the occurrence and the sites of PCD during the morphogenesis and differentiation of the retina and optic pathways of different vertebrates, and discuss the possible relationship between PCD and phagocytes during ontogeny. Copyright © 2014 Wiley Periodicals, Inc.

  13. Early Chordate Origin of the Vertebrate Integrin αI Domains

    PubMed Central

    Chouhan, Bhanupratap Singh; Käpylä, Jarmo; Denessiouk, Konstantin; Denesyuk, Alexander; Heino, Jyrki; Johnson, Mark S.

    2014-01-01

    Half of the 18 human integrins α subunits have an inserted αI domain yet none have been observed in species that have diverged prior to the appearance of the urochordates (ascidians). The urochordate integrin αI domains are not human orthologues but paralogues, but orthologues of human αI domains extend throughout later-diverging vertebrates and are observed in the bony fish with duplicate isoforms. Here, we report evidence for orthologues of human integrins with αI domains in the agnathostomes (jawless vertebrates) and later diverging species. Sequence comparisons, phylogenetic analyses and molecular modeling show that one nearly full-length sequence from lamprey and two additional fragments include the entire integrin αI domain region, have the hallmarks of collagen-binding integrin αI domains, and we show that the corresponding recombinant proteins recognize the collagen GFOGER motifs in a metal dependent manner, unlike the α1I domain of the ascidian C. intestinalis. The presence of a functional collagen receptor integrin αI domain supports the origin of orthologues of the human integrins with αI domains prior to the earliest diverging extant vertebrates, a domain that has been conserved and diversified throughout the vertebrate lineage. PMID:25409021

  14. Nervous systems and scenarios for the invertebrate-to-vertebrate transition

    PubMed Central

    Holland, Nicholas D.

    2016-01-01

    Older evolutionary scenarios for the origin of vertebrates often gave nervous systems top billing in accordance with the notion that a big-brained Homo sapiens crowned a tree of life shaped mainly by progressive evolution. Now, however, tree thinking positions all extant organisms equidistant from the tree's root, and molecular phylogenies indicate that regressive evolution is more common than previously suspected. Even so, contemporary theories of vertebrate origin still focus on the nervous system because of its functional importance, its richness in characters for comparative biology, and its central position in the two currently prominent scenarios for the invertebrate-to-vertebrate transition, which grew out of the markedly neurocentric annelid and enteropneust theories of the nineteenth century. Both these scenarios compare phyla with diverse overall body plans. This diversity, exacerbated by the scarcity of relevant fossil data, makes it challenging to establish plausible homologies between component parts (e.g. nervous system regions). In addition, our current understanding of the relation between genotype and phenotype is too preliminary to permit us to convert gene network data into structural features in any simple way. These issues are discussed here with special reference to the evolution of nervous systems during proposed transitions from invertebrates to vertebrates. PMID:26598728

  15. [Percutaneous biopsy evaluation in the diagnosis of thoracic and lumbar vertebral destruction syndrome].

    PubMed

    Rosales-Olivares, Luis Miguel; Valle-Cerna, Iván; Alpizar-Aguirre, Armando; Miramontes-Martínez, Victor; Arenas-Sordo, María de la Luz; Reyes-Sánchez, Alejandro

    2007-01-01

    The vertebral destruction syndrome is defined as those pathologies affecting the integrity of the vertebral structure, modifying its normal architecture and resulting in neurological deficit. Correct diagnosis is essential to define appropriate treatment. Biopsy, in addition to histopathological study, is a vital element for definitive diagnosis. We carried out a descriptive, deliberate interventional study in 20 patients with a diagnosis of vertebral destruction in whom a percutaneous transpendicular biopsy was done between January 2005 and July 2006. Variables analyzed were age, sex, affected segment, neurological condition, neurological deficit type, results of the biopsy and specific diagnosis. There was a predominance of males (55%). The lumbar spine was the most affected region in 80% of patients. Of the biopsies performed, 10% were reported as normal tissue, 20% with degenerative changes, 15% with inflammatory changes, 15% with primary tumoral lesion, 5% with chronic osteomyelitis, 10% with tuberculosis, 15% with tumoral metastasis and 10% necrotic devitalized bone tissue. Of these patients, 55% were treated nonsurgically, and the remaining 45% were treated surgically. No complications were reported. Percutaneous transpedicular biopsy has only 55% specificity in diagnosis and for that reason is a less useful diagnostic method in our setting for destructive lesion diagnosis from the vertebral body.

  16. Expression and evolution of Tiki1 and Tiki2 genes in vertebrates

    PubMed Central

    FEISTEL, KERSTIN; BRITO, JOSE M.; AMADO, NATHALIA G.; XU, CHIWEI; ABREU, JOSE G.; HE, XI

    2015-01-01

    Tiki1 is a Wnt protease and antagonist specifically expressed in the Spemann-Mangold Organizer and is required for head formation in Xenopus embryos. Here we report neighbor-joining phylogenetic analysis of vertebrate Tiki genes and their mRNA expression patterns in chick, mouse, and rabbit embryos. Tiki1 and Tiki2 orthologues are highly conserved, and exhibit similar but also different developmental expression patterns among the vertebrate/mammalian species analyzed. The Tiki1 gene is noticeably absent in the rodent lineage, but is present in lagomorphs and all other vertebrate/mammalian species examined. Expression in Hensen’s node, the equivalent of the Xenopus Organizer, was observed for Chick Tiki2 and Rabbit Tiki1 and Tiki2. Mouse Tiki2 was detected at low levels at gastrulation and head fold stages, but not in the node. Mouse Tiki2 and chick Tiki1 display similar expression in the dorsal spinal cord. Chick Tiki1 expression was also detected in the surface ectoderm and maxillary bud, while chick Tiki2 was found in the anterior intestinal portal, head mensenchyme and primitive atrium. Our expression analyses provide evidence that Tiki1 and Tiki2 are evolutionary conserved among vertebrate species and their expression in the Organizer and other regions suggests contributions of these Wnt inhibitors to embryonic patterning as well as organogenesis. Our analyses further reveal mis-regulation of TIKI1 and TIKI2 in human cancer and diseases. PMID:25354456

  17. The Role of the Vertebral End Plate in Low Back Pain

    PubMed Central

    Lotz, J. C.; Fields, A. J.; Liebenberg, E. C.

    2013-01-01

    End plates serve as the interface between rigid vertebral bodies and pliant intervertebral disks. Because the lumbar spine carries significant forces and disks don't have a dedicated blood supply, end plates must balance conflicting requirements of being strong to prevent vertebral fracture and porous to facilitate transport between disk cells and vertebral capillaries. Consequently, end plates are particularly susceptible to damage, which can increase communication between proinflammatory disk constituents and vascularized vertebral bone marrow. Damaged end plate regions can be sites of reactive bone marrow lesions that include proliferating nerves, which are susceptible to chemical sensitization and mechanical stimulation. Although several lines of evidence indicate that innervated end plate damage can be a source of chronic low back pain, its role in patients is likely underappreciated because innervated damage is poorly visualized with diagnostic imaging. This literature review summarizes end plate biophysical function and aspects of pathologic degeneration that can lead to vertebrogenic pain. Areas of future research are identified in the context of unmet clinical needs for patients with chronic low back pain. PMID:24436866

  18. Control of Vertebrate Skeletal Mineralization by Polyphosphates

    PubMed Central

    Omelon, Sidney; Georgiou, John; Henneman, Zachary J.; Wise, Lisa M.; Sukhu, Balram; Hunt, Tanya; Wynnyckyj, Chrystia; Holmyard, Douglas; Bielecki, Ryszard; Grynpas, Marc D.

    2009-01-01

    Background Skeletons are formed in a wide variety of shapes, sizes, and compositions of organic and mineral components. Many invertebrate skeletons are constructed from carbonate or silicate minerals, whereas vertebrate skeletons are instead composed of a calcium phosphate mineral known as apatite. No one yet knows why the dynamic vertebrate skeleton, which is continually rebuilt, repaired, and resorbed during growth and normal remodeling, is composed of apatite. Nor is the control of bone and calcifying cartilage mineralization well understood, though it is thought to be associated with phosphate-cleaving proteins. Researchers have assumed that skeletal mineralization is also associated with non-crystalline, calcium- and phosphate-containing electron-dense granules that have been detected in vertebrate skeletal tissue prepared under non-aqueous conditions. Again, however, the role of these granules remains poorly understood. Here, we review bone and growth plate mineralization before showing that polymers of phosphate ions (polyphosphates: (PO3−)n) are co-located with mineralizing cartilage and resorbing bone. We propose that the electron-dense granules contain polyphosphates, and explain how these polyphosphates may play an important role in apatite biomineralization. Principal Findings/Methodology The enzymatic formation (condensation) and destruction (hydrolytic degradation) of polyphosphates offers a simple mechanism for enzymatic control of phosphate accumulation and the relative saturation of apatite. Under circumstances in which apatite mineral formation is undesirable, such as within cartilage tissue or during bone resorption, the production of polyphosphates reduces the free orthophosphate (PO43−) concentration while permitting the accumulation of a high total PO43− concentration. Sequestering calcium into amorphous calcium polyphosphate complexes can reduce the concentration of free calcium. The resulting reduction of both free PO43− and free

  19. Control of vertebrate skeletal mineralization by polyphosphates.

    PubMed

    Omelon, Sidney; Georgiou, John; Henneman, Zachary J; Wise, Lisa M; Sukhu, Balram; Hunt, Tanya; Wynnyckyj, Chrystia; Holmyard, Douglas; Bielecki, Ryszard; Grynpas, Marc D

    2009-05-20

    Skeletons are formed in a wide variety of shapes, sizes, and compositions of organic and mineral components. Many invertebrate skeletons are constructed from carbonate or silicate minerals, whereas vertebrate skeletons are instead composed of a calcium phosphate mineral known as apatite. No one yet knows why the dynamic vertebrate skeleton, which is continually rebuilt, repaired, and resorbed during growth and normal remodeling, is composed of apatite. Nor is the control of bone and calcifying cartilage mineralization well understood, though it is thought to be associated with phosphate-cleaving proteins. Researchers have assumed that skeletal mineralization is also associated with non-crystalline, calcium- and phosphate-containing electron-dense granules that have been detected in vertebrate skeletal tissue prepared under non-aqueous conditions. Again, however, the role of these granules remains poorly understood. Here, we review bone and growth plate mineralization before showing that polymers of phosphate ions (polyphosphates: (PO(3)(-))(n)) are co-located with mineralizing cartilage and resorbing bone. We propose that the electron-dense granules contain polyphosphates, and explain how these polyphosphates may play an important role in apatite biomineralization. The enzymatic formation (condensation) and destruction (hydrolytic degradation) of polyphosphates offers a simple mechanism for enzymatic control of phosphate accumulation and the relative saturation of apatite. Under circumstances in which apatite mineral formation is undesirable, such as within cartilage tissue or during bone resorption, the production of polyphosphates reduces the free orthophosphate (PO(4)(3-)) concentration while permitting the accumulation of a high total PO(4)(3-) concentration. Sequestering calcium into amorphous calcium polyphosphate complexes can reduce the concentration of free calcium. The resulting reduction of both free PO(4)(3-) and free calcium lowers the relative apatite

  20. Light adaptation and the evolution of vertebrate photoreceptors.

    PubMed

    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

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

    PubMed

    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

  2. Expression of temperature-sensitive ion channel TRPM8 in sperm cells correlates with vertebrate evolution

    PubMed Central

    Majhi, Rakesh Kumar; Saha, Somdatta; Kumar, Ashutosh; Ghosh, Arijit; Swain, Nirlipta; Goswami, Luna; Mohapatra, Pratyush; Maity, Apratim; Kumar Sahoo, Vivek

    2015-01-01

    Transient Receptor Potential cation channel, subfamily Melastatin, member 8 (TRPM8) is involved in detection of cold temperature, different noxious compounds and in execution of thermo- as well as chemo-sensitive responses at cellular levels. Here we explored the molecular evolution of TRPM8 by analyzing sequences from various species. We elucidate that several regions of TRPM8 had different levels of selection pressure but the 4th–5th transmembrane regions remain highly conserved. Analysis of synteny suggests that since vertebrate origin, TRPM8 gene is linked with SPP2, a bone morphogen. TRPM8, especially the N-terminal region of it, seems to be highly variable in human population. We found 16,656 TRPM8 variants in 1092 human genomes with top variations being SNPs, insertions and deletions. A total of 692 missense mutations are also mapped to human TRPM8 protein of which 509 seem to be delateroiours in nature as supported by Polyphen V2, SIFT and Grantham deviation score. Using a highly specific antibody, we demonstrate that TRPM8 is expressed endogenously in the testis of rat and sperm cells of different vertebrates ranging from fish to higher mammals. We hypothesize that TRPM8 had emerged during vertebrate evolution (ca 450 MYA). We propose that expression of TRPM8 in sperm cell and its role in regulating sperm function are important factors that have guided its molecular evolution, and that these understandings may have medical importance. PMID:26500819

  3. Cost minimization by helpers in cooperative vertebrates.

    PubMed

    Russell, A F; Sharpe, L L; Brotherton, P N M; Clutton-Brock, T H

    2003-03-18

    When parents invest heavily in reproduction they commonly suffer significant energetic costs. Parents reduce the long-term fitness implications of these costs through increased foraging and reduced reproductive investment in the future. Similar behavioral modifications might be expected among helpers in societies of cooperative vertebrates, in which helping is associated with energetic costs. By using multivariate analyses and experiments, we show that in cooperative meerkats, Suricata suricatta, helping is associated with substantial short-term growth costs but limited long-term fitness costs. This association forms because individual contributions to cooperation are initially condition dependent, and, because when helpers invest heavily in cooperation, they increase their foraging rate during the subsequent nonbreeding period and reduce their level of cooperative investment in the subsequent reproductive period. These results provide a unique demonstration that despite significant short-term costs, helpers, like breeders, are able to reduce the fitness consequences of these costs through behavioral modifications.

  4. Salmonella Typhi Vertebral Osteomyelitis and Epidural Abscess

    PubMed Central

    Chua, Ying Ying; Chen, John L. T.

    2016-01-01

    Salmonella vertebral osteomyelitis is an uncommon complication of Salmonella infection. We report a case of a 57-year-old transgender male who presented with lower back pain for a period of one month following a fall. Physical examination only revealed tenderness over the lower back with no neurological deficits. MRI of the thoracic and lumbar spine revealed a spondylodiscitis at T10-T11 and T12-L1 and right posterior epidural collection at the T9-T10 level. He underwent decompression laminectomy with segmental instrumentation and fusion of T8 to L3 vertebrae. Intraoperatively, he was found to have acute-on-chronic osteomyelitis in T10 and T11, epidural abscess, and discitis in T12-L1. Tissue and wound culture grew Salmonella Typhi and with antibiotics susceptibility guidance he was treated with intravenous ceftriaxone for a period of six weeks. He recovered well with no neurological deficits. PMID:27034871

  5. Estrogen receptor signaling during vertebrate development

    PubMed Central

    Bondesson, Maria; Hao, Ruixin; Lin, Chin-Yo; Williams, Cecilia; Gustafsson, Jan-Åke

    2014-01-01

    Estrogen receptors are expressed and their cognate ligands produced in all vertebrates, indicative of important and conserved functions. Through evolution estrogen has been involved in controlling reproduction, affecting both the development of reproductive organs and reproductive behavior. This review broadly describes the synthesis of estrogens and the expression patterns of aromatase and the estrogen receptors, in relation to estrogen functions in the developing fetus and child. We focus on the role of estrogens for development of reproductive tissues, as well as non-reproductive effects on the developing brain. We collate data from human, rodent, bird and fish studies and highlight common and species-specific effects of estrogen signaling on fetal development. Morphological malformations originating from perturbed estrogen signaling in estrogen receptor and aromatase knockout mice are discussed, as well as the clinical manifestations of rare estrogen receptor alpha and aromatase gene mutations in humans. PMID:24954179

  6. Planar Cell Polarity in vertebrate limb morphogenesis

    PubMed Central

    Gao, Bo; Yang, Yingzi

    2013-01-01

    Studies of the vertebrate limb development have contributed significantly to understanding the fundamental mechanisms underlying growth, patterning and morphogenesis of a complex multicellular organism. In the limb, well-defined signaling centers interact to coordinate limb growth and patterning along the three axes. Recent analyses of live imaging and mathematical modeling have provided evidence that polarized cell behaviors governed by morphogen gradients play an important role in shaping the limb bud. Furthermore, the Wnt/Planar Cell Polarity (PCP) pathway that controls uniformly polarized cellular behaviors in a field of cells has emerged to be critical for directional morphogenesis in the developing limb. Directional information coded in the morphogen gradient may be interpreted by responding cells through regulating the activities of PCP components in a Wnt morphogen dose-dependent manner. PMID:23747034

  7. Lysophosphatidic Acid (LPA) Signaling in Vertebrate Reproduction

    PubMed Central

    Ye, Xiaoqin; Chun, Jerold

    2009-01-01

    Lysophosphatidic acid (LPA) is a cell membrane phospholipid metabolite that can act as an extracellular signal. Its effects are mediated through at least five G protein-coupled receptors (GPCRs), LPA1-5, and likely others as well. Studies in multiple species including LPA receptor-deficient mice and humans have identified or implicated important roles for receptor-mediated LPA signaling in multiple aspects of vertebrate reproduction. These include ovarian function, spermatogenesis, fertilization, early embryo development, embryo implantation, embryo spacing, decidualization, pregnancy maintenance, and parturition. LPA signaling may also have pathological consequences, influencing aspects of endometriosis and ovarian cancer. Here we review recent progress in LPA signaling research relevant to female and male reproduction. PMID:19836970

  8. Cost minimization by helpers in cooperative vertebrates

    PubMed Central

    Russell, A. F.; Sharpe, L. L.; Brotherton, P. N. M.; Clutton-Brock, T. H.

    2003-01-01

    When parents invest heavily in reproduction they commonly suffer significant energetic costs. Parents reduce the long-term fitness implications of these costs through increased foraging and reduced reproductive investment in the future. Similar behavioral modifications might be expected among helpers in societies of cooperative vertebrates, in which helping is associated with energetic costs. By using multivariate analyses and experiments, we show that in cooperative meerkats, Suricata suricatta, helping is associated with substantial short-term growth costs but limited long-term fitness costs. This association forms because individual contributions to cooperation are initially condition dependent, and, because when helpers invest heavily in cooperation, they increase their foraging rate during the subsequent nonbreeding period and reduce their level of cooperative investment in the subsequent reproductive period. These results provide a unique demonstration that despite significant short-term costs, helpers, like breeders, are able to reduce the fitness consequences of these costs through behavioral modifications. PMID:12629209

  9. Pyogenic vertebral osteomyelitis/disc infection.

    PubMed

    Lehovsky, J

    1999-03-01

    Spinal osteomyelitis has been known about for centuries. Granulomatous infection was the principal offender in the past, but nowadays, with an increased number of patients at 'risk', the proportion of pyogenic infections has risen. Awareness of this is the essence of early diagnosis. The advent of magnetic resonance imaging has proved a major milestone; with its high sensitivity and specificity, it is an essential part of the diagnostic work-up. The treatment of spinal osteomyelitis follows the same basic principles as for any infection. Once the diagnosis has been established, early conservative treatment is commenced. Debridement, drainage of any abscesses, spinal decompression and stabilization are options in surgical treatment. The successful use of metallic implants to achieve correction and stabilization is probably helped by good perfusion of the vertebral body and accompanying good soft tissue coverage. The eradication of infection is therefore still possible.

  10. Planar cell polarity in vertebrate limb morphogenesis.

    PubMed

    Gao, Bo; Yang, Yingzi

    2013-08-01

    Studies of the vertebrate limb development have contributed significantly to understanding the fundamental mechanisms underlying growth, patterning, and morphogenesis of a complex multicellular organism. In the limb, well-defined signaling centers interact to coordinate limb growth and patterning along the three axes. Recent analyses of live imaging and mathematical modeling have provided evidence that polarized cell behaviors governed by morphogen gradients play an important role in shaping the limb bud. Furthermore, the Wnt/planar cell polarity (PCP) pathway that controls uniformly polarized cell behaviors in a field of cells has emerged to be critical for directional morphogenesis in the developing limb. Directional information coded in the morphogen gradient may be interpreted by responding cells through regulating the activities of PCP components in a Wnt morphogen dose-dependent manner.

  11. The molecular regulation of vertebrate limb patterning.

    PubMed

    Butterfield, Natalie C; McGlinn, Edwina; Wicking, Carol

    2010-01-01

    The limb has long been considered a paradigm for organogenesis because of its simplicity and ease of manipulation. However, it has become increasingly clear that the processes required to produce a perfectly formed limb involve complex molecular interactions across all three axes of limb development. Old models have evolved with acquisition of molecular knowledge, and in more recent times mathematical modeling approaches have been invoked to explain the precise spatio-temporal regulation of gene networks that coordinate limb patterning and outgrowth. This review focuses on recent advances in our understanding of vertebrate limb development, highlighting the signaling interactions required to lay down the pattern on which the processes of differentiation will act to ultimately produce the final limb.

  12. Morphogenesis and evolution of vertebrate appendicular muscle

    PubMed Central

    HAINES, LYNN; CURRIE, PETER D.

    2001-01-01

    Two different modes are utilised by vertebrate species to generate the appendicular muscle present within fins and limbs. Primitive Chondricthyan or cartilaginous fishes use a primitive mode of muscle formation to generate the muscle of the fins. Direct epithelial myotomal extensions invade the fin and generate the fin muscles while remaining in contact with the myotome. Embryos of amniotes such as chick and mouse use a similar mechanism to that deployed in the bony teleost species, zebrafish. Migratory mesenchymal myoblasts delaminate from fin/limb level somites, migrate to the fin/limb field and differentiate entirely within the context of the fin/limb bud. Migratory fin and limb myoblasts express identical genes suggesting that they possess both morphogenetic and molecular identity. We conclude that the mechanisms controlling tetrapod limb muscle formation arose prior to the Sarcopterygian or tetrapod radiation. PMID:11523824

  13. High-throughput hyperdimensional vertebrate phenotyping

    PubMed Central

    Pardo-Martin, Carlos; Allalou, Amin; Medina, Jaime; Eimon, Peter M.; Wählby, Carolina; Yanik, Mehmet Fatih

    2013-01-01

    Most gene mutations and biologically active molecules cause complex responses in animals that cannot be predicted by cell culture models. Yet animal studies remain too slow and their analyses are often limited to only a few readouts. Here we demonstrate high-throughput optical projection tomography with micrometer resolution and hyperdimensional screening of entire vertebrates in tens of seconds using a simple fluidic system. Hundreds of independent morphological features and complex phenotypes are automatically captured in three dimensions with unprecedented speed and detail in semi-transparent zebrafish larvae. By clustering quantitative phenotypic signatures, we can detect and classify even subtle alterations in many biological processes simultaneously. We term our approach hyperdimensional in vivo phenotyping (HIP). To illustrate the power of HIP, we have analyzed the effects of several classes of teratogens on cartilage formation using 200 independent morphological measurements and identified similarities and differences that correlate well with their known mechanisms of actions in mammals. PMID:23403568

  14. [Aggressive vertebral hemangiomas: optimization of management tactics].

    PubMed

    Kravtsov, M N; Manukovskiĭ, V A; Zharinov, G M; Kandyba, D V; Tsibirov, A A; Savello, A V; Svistov, D V

    2012-01-01

    Today vertebral hemangioma is not completely understood entity, neither its pathogenesis nor optimal treatment is determined. Nowadays in majority of clinics in this country ineffective radiotherapy remains the first-line treatment. We analyzed results of treatment of 205 patients (286 lesions) with aggressive hemangiomas operated in Department of Neurosurgery of Military Medical Academy and Department of Nuclear Medicine of of Russian Scientific Center of Radiological and Surgical Technologies (Saint-Petersburg, Russia) since 1999 till 2009. Percutaneus vertebroplasty was performed in 167 lesions, radiotherapy was applied in 119 aggressive hemangiomas. Vertebroplasty is more effective for treatment of aggressive hemangiomas in comparison with radiotherapy. Signs of hemangiomas aggression, indications for surgery, and tactics of management were determined. Use of percutaneous vertebroplasty for treatment of aggressive hemangiomas resulted in fast recovery of the patients. This procedure is minimally invasive, it reduces hospital stay and duration of recovery.

  15. Magnetic Susceptibility in the Vertebral Column

    NASA Astrophysics Data System (ADS)

    Schick, F.; Nagele, T.; Lutz, O.; Pfeffer, K.; Giehl, J.

    1994-01-01

    A magnetic resonance method is described which provides good-quality field-mapping images of the spine, although the in vivo signals from red bone marrow of the vertebral bodies exhibit similar fractions of lipid and water protons with their chemical-shift difference of 3.4 ppm. The susceptibilities of bone marrow and intervertebral disks were examined in 20 cadaveric human spines, 9 healthy volunteers, and 9 patients with degenerative disk alterations. The influence of geometrical properties was studied in cylindrical spine phantoms of different size and contents with different susceptibility. The measurements reveal interindividual differences of the susceptibility of the intervertebral disks in healthy subjects. Three out of nine degenerated disks with low signal in T2-weighted spin-echo images showed irregularities of the field distribution within the nucleus pulposus.

  16. Evolutionary conservation of regulatory elements in vertebrate Hox gene clusters.

    PubMed

    Santini, Simona; Boore, Jeffrey L; Meyer, Axel

    2003-06-01

    Comparisons of DNA sequences among evolutionarily distantly related genomes permit identification of conserved functional regions in noncoding DNA. Hox genes are highly conserved in vertebrates, occur in clusters, and are uninterrupted by other genes. We aligned (PipMaker) the nucleotide sequences of the HoxA clusters of tilapia, pufferfish, striped bass, zebrafish, horn shark, human, and mouse, which are separated by approximately 500 million years of evolution. In support of our approach, several identified putative regulatory elements known to regulate the expression of Hox genes were recovered. The majority of the newly identified putative regulatory elements contain short fragments that are almost completely conserved and are identical to known binding sites for regulatory proteins (Transfac database). The regulatory intergenic regions located between the genes that are expressed most anteriorly in the embryo are longer and apparently more evolutionarily conserved than those at the other end of Hox clusters. Different presumed regulatory sequences are retained in either the Aalpha or Abeta duplicated Hox clusters in the fish lineages. This suggests that the conserved elements are involved in different gene regulatory networks and supports the duplication-deletion-complementation model of functional divergence of duplicated genes.

  17. Aquatic vertebrate assemblages of the upper Clear Creek Watershed, California

    USGS Publications Warehouse

    Brown, L.R.; May, J.T.

    2007-01-01

    We sampled streams in the Upper Clear Creek Watershed in northwestern California in fall 2004 and fall 2005 to document assemblages of aquatic vertebrates and to provide resource managers with information on the importance of these assemblages in terms of regional biodiversity. We used single-pass backpack electrofishing to sample 15 sites in fall 2004 and the same 15 sites plus 4 new sites in fall 2005. We captured 10 fish taxa and 2 species of larval amphibians. Seven of the fish taxa were native species. Of the exotic species, only brook trout (Salvelinus fontinalis) occurred at more than 1 site. Ordinations by nonmetric multidimensional scaling indicated a gradient from sites with rainbow trout (Oncorhynchus mykiss), Pacific giant salamander (Dicamptodon tenebrosus), and tailed frog (Ascaphus truei) to sites dominated by riffle sculpin (Cottus gulosus), California roach (Hesperoleucas symmetricus), and Sacramento sucker (Catostomus occidentalis). The gradient in species composition was associated with changes in elevation, gradient, discharge, and substrate. The Upper Clear Creek Watershed represents a unique area of overlap between the North Coast California amphibian fauna and the Central Valley fish fauna with a notable paucity of exotic fishes and amphibians. Preservation of the integrity of native aquatic assemblages is an important goal for aquatic resource management in the region; our results provide a critcial baseline to gauge future management actions.

  18. Evolutionary conservation of regulatory elements in vertebrate HOX gene clusters

    SciTech Connect

    Santini, Simona; Boore, Jeffrey L.; Meyer, Axel

    2003-12-31

    Due to their high degree of conservation, comparisons of DNA sequences among evolutionarily distantly-related genomes permit to identify functional regions in noncoding DNA. Hox genes are optimal candidate sequences for comparative genome analyses, because they are extremely conserved in vertebrates and occur in clusters. We aligned (Pipmaker) the nucleotide sequences of HoxA clusters of tilapia, pufferfish, striped bass, zebrafish, horn shark, human and mouse (over 500 million years of evolutionary distance). We identified several highly conserved intergenic sequences, likely to be important in gene regulation. Only a few of these putative regulatory elements have been previously described as being involved in the regulation of Hox genes, while several others are new elements that might have regulatory functions. The majority of these newly identified putative regulatory elements contain short fragments that are almost completely conserved and are identical to known binding sites for regulatory proteins (Transfac). The conserved intergenic regions located between the most rostrally expressed genes in the developing embryo are longer and better retained through evolution. We document that presumed regulatory sequences are retained differentially in either A or A clusters resulting from a genome duplication in the fish lineage. This observation supports both the hypothesis that the conserved elements are involved in gene regulation and the Duplication-Deletion-Complementation model.

  19. Prostaglandin E2 regulates vertebrate haematopoietic stem cell homeostasis

    PubMed Central

    North, Trista E.; Goessling, Wolfram; Walkley, Carl R.; Lengerke, Claudia; Kopani, Kamden R.; Lord, Allegra M.; Weber, Gerhard J.; Bowman, Teresa V.; Jang, Il-Ho; Grosser, Tilo; FitzGerald, Garret A.; Daley, George Q.; Orkin, Stuart H.; Zon, Leonard I.

    2009-01-01

    Haematopoietic stem cell (HSC) homeostasis is tightly controlled by growth factors, signalling molecules and transcription factors. Definitive HSCs derived during embryogenesis in the aorta-gonad-mesonephros region subsequently colonize fetal and adult haematopoietic organs1,2. To identify new modulators of HSC formation and homeostasis, a panel of biologically active compounds was screened for effects on stem cell induction in the zebrafish aorta-gonad-mesonephros region. Here, we show that chemicals that enhance prostaglandin (PG) E2 synthesis increased HSC numbers, and those that block prostaglandin synthesis decreased stem cell numbers. The cyclooxygenases responsible for PGE2 synthesis were required for HSC formation. A stable derivative of PGE2 improved kidney marrow recovery following irradiation injury in the adult zebrafish. In murine embryonic stem cell differentiation assays, PGE2 caused amplification of multipotent progenitors. Furthermore, ex vivo exposure to stabilized PGE2 enhanced spleen colony forming units at day 12 post transplant and increased the frequency of long-term repopulating HSCs present in murine bone marrow after limiting dilution competitive transplantation. The conserved role for PGE2 in the regulation of vertebrate HSC homeostasis indicates that modulation of the prostaglandin pathway may facilitate expansion of HSC number for therapeutic purposes. PMID:17581586

  20. Evolutionary Conservation of Regulatory Elements in Vertebrate Hox Gene Clusters

    PubMed Central

    Santini, Simona; Boore, Jeffrey L.; Meyer, Axel

    2003-01-01

    Comparisons of DNA sequences among evolutionarily distantly related genomes permit identification of conserved functional regions in noncoding DNA. Hox genes are highly conserved in vertebrates, occur in clusters, and are uninterrupted by other genes. We aligned (PipMaker) the nucleotide sequences of the HoxA clusters of tilapia, pufferfish, striped bass, zebrafish, horn shark, human, and mouse, which are separated by approximately 500 million years of evolution. In support of our approach, several identified putative regulatory elements known to regulate the expression of Hox genes were recovered. The majority of the newly identified putative regulatory elements contain short fragments that are almost completely conserved and are identical to known binding sites for regulatory proteins (Transfac database). The regulatory intergenic regions located between the genes that are expressed most anteriorly in the embryo are longer and apparently more evolutionarily conserved than those at the other end of Hox clusters. Different presumed regulatory sequences are retained in either the Aα or Aβ duplicated Hox clusters in the fish lineages. This suggests that the conserved elements are involved in different gene regulatory networks and supports the duplication-deletion-complementation model of functional divergence of duplicated genes. PMID:12799348

  1. Kinesin-2 family in vertebrate ciliogenesis

    PubMed Central

    Zhao, Chengtian; Omori, Yoshihiro; Brodowska, Katarzyna; Kovach, Peter; Malicki, Jarema

    2012-01-01

    The differentiation of cilia is mediated by kinesin-driven transport. As the function of kinesins in vertebrate ciliogenesis is poorly characterized, we decided to determine the role of kinesin-2 family motors—heterotrimeric kinesin-II and the homodimeric Kif17 kinesin—in zebrafish cilia. We report that kif17 is largely dispensable for ciliogenesis; kif17 homozygous mutant animals are viable and display subtle morphological defects of olfactory cilia only. In contrast to that, the kif3b gene, encoding a heterotrimeric kinesin subunit, is necessary for cilia differentiation in most tissues, although exceptions exist, and include photoreceptors and a subset of hair cells. Cilia of these cell types persist even in kif3b/kif17 double mutants. Although we have not observed a functional redundancy of kif3b and kif17, kif17 is able to substitute for kif3b in some cilia. In contrast to kif3b/kif17 double mutants, simultaneous interference with kif3b and kif3c leads to the complete loss of photoreceptor and hair cell cilia, revealing redundancy of function. This is in agreement with the idea that Kif3b and Kif3c motor subunits form complexes with Kif3a, but not with each other. Interestingly, kif3b mutant photoreceptor cilia differentiate with a delay, suggesting that kif3c, although redundant with kif3b at later stages of differentiation, is not active early in photoreceptor ciliogenesis. Consistent with that, the overexpression of kif3c in kif3b mutants rescues early photoreceptor cilia defects. These data reveal unexpected diversity of functional relationships between vertebrate ciliary kinesins, and show that the repertoire of kinesin motors changes in some cilia during their differentiation. PMID:22308397

  2. Gangliosides of the Vertebrate Nervous System.

    PubMed

    Schnaar, Ronald L

    2016-08-14

    Gangliosides, sialylated glycosphingolipids, found on all vertebrate cells and tissues, are major molecular determinants on the surfaces of vertebrate nerve cells. Composed of a sialylated glycan attached to a ceramide lipid, the same four structures-GM1, GD1a, GD1b, and GT1b-represent the vast majority (>90%) of gangliosides in the brains of all mammals and birds. Primarily found on the outer surface of the plasma membrane with their glycans facing outward, gangliosides associate laterally with each other, sphingomyelin, cholesterol, and select proteins in lipid rafts-the dynamic functional subdomains of the plasma membrane. The functions of gangliosides in the human nervous system are revealed by congenital mutations in ganglioside biosynthetic genes. Mutations in ST3GAL5, which codes for an enzyme early in brain ganglioside biosynthesis, result in an early-onset seizure disorder with profound motor and cognitive decay, whereas mutations in B4GALNT1, a gene encoding a later step, result in hereditary spastic paraplegia accompanied by intellectual deficits. The molecular functions of brain gangliosides include regulation of receptors in the same membrane via lateral (cis) associations and regulation of cell-cell recognition by trans interaction with ganglioside binding proteins on apposing cells. Gangliosides also affect the aggregation of Aβ (Alzheimer's disease) and α-synuclein (Parkinson's Disease). As analytical, biochemical, and genetic tools advance, research on gangliosides promises to reveal mechanisms of molecular control related to nerve and glial cell differentiation, neuronal excitability, axon outgrowth after nervous system injury, and protein folding in neurodegenerative diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Vertebral surface registration using ridgelines/crestlines

    NASA Astrophysics Data System (ADS)

    Tan, Sovira; Yao, Jianhua; Yao, Lawrence; Summers, Ronald M.; Ward, Michael M.

    2008-03-01

    The Iterative Closest Point (ICP) algorithm is an efficient and popular technique for surface registration. It however suffers from the well-known problem of local minima that make the algorithm stop before it reaches the desired global solution. ICP can be improved by the use of landmarks or features. We recently developed a level set capable of evolving on the surface of an object represented by a triangular mesh. This level set permits the segmentation of portions of a surface based on curvature features. The boundary of a segmented portion forms a ridgeline/crestline. We show that the ridgelines/crestlines and corresponding enclosed surfaces extracted by the algorithm can substantially improve ICP registration. We compared the performance of an ICP algorithm in three setups: 1) ICP without landmarks. 2) ICP using ridgelines. 3) ICP using ridgelines and corresponding enclosed surfaces. Our material consists of vertebral body surfaces extracted for a study about the progression of Ankylosing Spondylitis. Same vertebrae scanned at intervals of one or two years were rigidly registered. Vertebral body rims and the end plate surfaces they enclose were used as landmarks. The performance measure was the mean error distance between the registered surfaces. From the one hundred registrations that we performed the average mean error was respectively 0.503mm, 0.335mm and 0.254mm for the three setups. Setup 3 almost halved the average error of setup 1. Moreover the error range is dramatically reduced from [0.0985, 2.19]mm to just [0.0865, 0.532]mm, making the algorithm very robust.

  4. Ranking terrestrial vertebrate species for utility in biomonitoring and vulnerability to environmental contaminants

    USGS Publications Warehouse

    Golden, N.H.; Rattner, B.A.

    2003-01-01

    The measurement of contaminant tissue concentrations or exposure-related effects in biota has been used extensively to monitor pollution and environmental health. Terrestrial vertebrates have historically been an important group of species in such evaluations, not only because many are excellent sentinels of environmental contamination, but also because they are valued natural resources in their own right that may be adversely affected by toxicant exposure. Selection of appropriate vertebrates for biomonitoring studies frequently relies on expert opinion, although a few rigorous schemes are in use for predicting vulnerability of birds to the adverse effects of petroleum crude oil. A Utility Index that ranks terrestrial vertebrate species as potential sentinels of contaminants in a region, and a Vulnerability Index that assesses the threat of specific groups of contaminants to these species, have been developed to assist decision makers in risk assessments of persistent organic pollutants, cholinesterase-inhibiting pesticides, petroleum crude oil, mercury, and lead shot. Twenty-five terrestrial vertebrate species commonly found in Atlantic Coast estuarine habitat were ranked for their utility as biomonitors of contamination and their vulnerability to pollutants in this region. No single species, taxa or class of vertebrates was found to be an ideal sentinel for all groups of contaminants. Although birds have overwhelmingly been used to monitor contaminants compared to other terrestrial vertebrate classes, the non-migratory nature and dietary habits of the snapping turtle and mink consistently resulted in ranking these species excellent sentinels as well. Vulnerability of Atlantic Coast populations of these species varied considerably among groups of contaminants. Usually a particular species was found to be at high risk to only one or two groups of contaminants, although a noteworthy exception is the bald eagle that is highly vulnerable to all five of the

  5. Vertebrate Osmoregulation: A Student Laboratory Exercise Using Teleost Fish

    ERIC Educational Resources Information Center

    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…

  6. Cooperative Learning as a Tool To Teach Vertebrate Anatomy.

    ERIC Educational Resources Information Center

    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)

  7. Collection & Processing of Vertebrate Specimens for Arbovirus Studies.

    ERIC Educational Resources Information Center

    Sudia, W. Daniel; And Others

    Described are techniques used by the National Communicable Disease Center in obtaining blood and tissues from man and other vertebrates for arbovirus isolation and antibody studies. Also included are techniques for capturing and handling vertebrates; banding and marking; restraining and bleeding; storing of specimens to preserve antibody and…

  8. Insights into vertebrate evolution from the chicken genome sequence

    PubMed Central

    Furlong, Rebecca F

    2005-01-01

    The chicken has recently joined the ever-growing list of fully sequenced animal genomes. Its unique features include expanded gene families involved in egg and feather production as well as more surprising large families, such as those for olfactory receptors. Comparisons with other vertebrate genomes move us closer to defining a set of essential vertebrate genes. PMID:15693954

  9. [A digital radiology method for assessing vertebral osteoporosis].

    PubMed

    Diacinti, D; Acca, M; Tomei, E

    1996-01-01

    The radiologic identification of vertebral fractures is usually subjective and reproducibility is poor. This paper describes a new digital radiologic method to perform vertebral morphometry, i.e. osteoradiometry (ORM). Lateral radiographs of the thoracic and lumbar spine were obtained in 50 premenopausal women and digitalized by means of a video camera. A special computer software enables to calculate the anterior (Ha), middle (Hm), and posterior (Hp) heights of vertebral bodies (T4-L5) and the morphometric indices of vertebral fractures. ORM reproducibility was assessed by comparing repeated measurements made by two radiologists: the intra- and interobserver variation coefficients (CV) were respectively 1.5% and 2.3% for Hp; 1.3% and 2% for Hm; 1.4% and 2.1% for Ha. The normal range for vertebral dimensions was therefore established. The anterior and posterior heights increased from T4 to L2, but for L3-L5 the posterior height was lower than the anterior height (Ha/Hp > 1). Vertebral heights positively correlated with the standing heights of the subjects (r = 0.2, p < 0.05). Weight and the body mass index (BMI) were not correlated with vertebral heights. These normal values, compared with those found in osteoporosis patients, will allow to assess ORM diagnostic efficacy in identifying vertebral fractures.

  10. Checklist of vertebrate animals of the Cascade Head Experimental Forest.

    Treesearch

    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...

  11. Variability and constraint in the mammalian vertebral column.

    PubMed

    Asher, R J; Lin, K H; Kardjilov, N; Hautier, L

    2011-05-01

    Patterns of vertebral variation across mammals have seldom been quantified, making it difficult to test hypotheses of covariation within the axial skeleton and mechanisms behind the high level of vertebral conservatism among mammals. We examined variation in vertebral counts within 42 species of mammals, representing monotremes, marsupials and major clades of placentals. These data show that xenarthrans and afrotherians have, on average, a high proportion of individuals with meristic deviations from species' median series counts. Monotremes, xenarthrans, afrotherians and primates show relatively high variation in thoracolumbar vertebral count. Among the clades sampled in our dataset, rodents are the least variable, with several species not showing any deviations from median vertebral counts, or vertebral anomalies such as asymmetric ribs or transitional vertebrae. Most mammals show significant correlations between sacral position and length of the rib cage; only a few show a correlation between sacral position and number of sternebrae. The former result is consistent with the hypothesis that adult axial skeletal structures patterned by distinct mesodermal tissues are modular and covary; the latter is not. Variable levels of correlation among these structures may indicate that the boundaries of prim/abaxial mesodermal precursors of the axial skeleton are not uniform across species. We do not find evidence for a higher frequency of vertebral anomalies in our sample of embryos or neonates than in post-natal individuals of any species, contrary to the hypothesis that stabilizing selection plays a major role in vertebral patterning.

  12. Cooperative Learning as a Tool To Teach Vertebrate Anatomy.

    ERIC Educational Resources Information Center

    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)

  13. Vertebrate Osmoregulation: A Student Laboratory Exercise Using Teleost Fish

    ERIC Educational Resources Information Center

    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…

  14. Fossil jawless fish from China foreshadows early jawed vertebrate anatomy.

    PubMed

    Gai, Zhikun; Donoghue, Philip C J; Zhu, Min; Janvier, Philippe; Stampanoni, Marco

    2011-08-17

    Most living vertebrates are jawed vertebrates (gnathostomes), and the living jawless vertebrates (cyclostomes), hagfishes and lampreys, provide scarce information about the profound reorganization of the vertebrate skull during the evolutionary origin of jaws. The extinct bony jawless vertebrates, or 'ostracoderms', are regarded as precursors of jawed vertebrates and provide insight into this formative episode in vertebrate evolution. Here, using synchrotron radiation X-ray tomography, we describe the cranial anatomy of galeaspids, a 435-370-million-year-old 'ostracoderm' group from China and Vietnam. The paired nasal sacs of galeaspids are located anterolaterally in the braincase, and the hypophyseal duct opens anteriorly towards the oral cavity. These three structures (the paired nasal sacs and the hypophyseal duct) were thus already independent of each other, like in gnathostomes and unlike in cyclostomes and osteostracans (another 'ostracoderm' group), and therefore have the condition that current developmental models regard as prerequisites for the development of jaws. This indicates that the reorganization of vertebrate cranial anatomy was not driven deterministically by the evolutionary origin of jaws but occurred stepwise, ultimately allowing the rostral growth of ectomesenchyme that now characterizes gnathostome head development.

  15. Height Loss, Vertebral Fractures, and the Misclassification of Osteoporosis

    PubMed Central

    Xu, WanWan; Perera, Subashan; Medich, Donna; Fiorito, Gail; Wagner, Julie; Berger, Loretta K.; Greenspan, Susan L.

    2010-01-01

    Background The presence of a vertebral fracture identifies a patient who has clinical osteoporosis. However, approximately 2/3 to 3/4 of VFs are asymptomatic. Vertebral Fracture Assessment is a method derived from dual-xray absorptiometry (DXA) to assess vertebral fractures. The objectives of this study were 1) to determine the association between the degree of height loss in older men and women and risk of a vertebral fracture, and 2) to determine if knowledge of vertebral fractures will alter the classification of osteoporosis based on bone mineral density alone. Methods 231 men and women over the age of 65 underwent DXA scan of their spine and hip (including bone mineral density and Vertebral Fracture Assessment), measurement of their height, and a questionnaire. Results We found that height loss was significantly associated with a vertebral fracture (p=0.0160). The magnitude of the association translates to a 19% increase in odds for 1/2 inch and 177% for 3 inches. Although 45% had osteoporosis by either bone mineral density or fracture criteria, 30% would have been misclassified if bone mineral density criteria were used alone. Conclusions Height loss is an indicator for the presence of vertebral fractures. Bone mineral density criteria alone may misclassify older patients who have osteoporosis. PMID:20870048

  16. Solitary thoracic vertebral body cysticercosis presenting with progressive compressive myelopathy.

    PubMed

    Furtado, Sunil V; Dadlani, Ravi; Ghosal, Nandita; Rao, Arun S

    2013-04-01

    Common bony spinal pathologies that could present with progressive spasticity include vertebral body tumors or chronic infections of the spine. Cysticercosis of the spine commonly has an intramedullary occurrence. The authors discuss the presentation and management of a rare case of solitary vertebral cysticercosis that presented with lower-limb spasticity and sphincter involvement.

  17. Evolutionary Genomics and Adaptive Evolution of the Hedgehog Gene Family (Shh, Ihh and Dhh) in Vertebrates

    PubMed Central

    Pereira, Joana; Johnson, Warren E.; O’Brien, Stephen J.; Jarvis, Erich D.; Zhang, Guojie; Gilbert, M. Thomas P.; Vasconcelos, Vitor; Antunes, Agostinho

    2014-01-01

    The Hedgehog (Hh) gene family codes for a class of secreted proteins composed of two active domains that act as signalling molecules during embryo development, namely for the development of the nervous and skeletal systems and the formation of the testis cord. While only one Hh gene is found typically in invertebrate genomes, most vertebrates species have three (Sonic hedgehog – Shh; Indian hedgehog – Ihh; and Desert hedgehog – Dhh), each with different expression patterns and functions, which likely helped promote the increasing complexity of vertebrates and their successful diversification. In this study, we used comparative genomic and adaptive evolutionary analyses to characterize the evolution of the Hh genes in vertebrates following the two major whole genome duplication (WGD) events. To overcome the lack of Hh-coding sequences on avian publicly available databases, we used an extensive dataset of 45 avian and three non-avian reptilian genomes to show that birds have all three Hh paralogs. We find suggestions that following the WGD events, vertebrate Hh paralogous genes evolved independently within similar linkage groups and under different evolutionary rates, especially within the catalytic domain. The structural regions around the ion-binding site were identified to be under positive selection in the signaling domain. These findings contrast with those observed in invertebrates, where different lineages that experienced gene duplication retained similar selective constraints in the Hh orthologs. Our results provide new insights on the evolutionary history of the Hh gene family, the functional roles of these paralogs in vertebrate species, and on the location of mutational hotspots. PMID:25549322

  18. Evolutionary genomics and adaptive evolution of the Hedgehog gene family (Shh, Ihh and Dhh) in vertebrates.

    PubMed

    Pereira, Joana; Johnson, Warren E; O'Brien, Stephen J; Jarvis, Erich D; Zhang, Guojie; Gilbert, M Thomas P; Vasconcelos, Vitor; Antunes, Agostinho

    2014-01-01

    The Hedgehog (Hh) gene family codes for a class of secreted proteins composed of two active domains that act as signalling molecules during embryo development, namely for the development of the nervous and skeletal systems and the formation of the testis cord. While only one Hh gene is found typically in invertebrate genomes, most vertebrates species have three (Sonic hedgehog--Shh; Indian hedgehog--Ihh; and Desert hedgehog--Dhh), each with different expression patterns and functions, which likely helped promote the increasing complexity of vertebrates and their successful diversification. In this study, we used comparative genomic and adaptive evolutionary analyses to characterize the evolution of the Hh genes in vertebrates following the two major whole genome duplication (WGD) events. To overcome the lack of Hh-coding sequences on avian publicly available databases, we used an extensive dataset of 45 avian and three non-avian reptilian genomes to show that birds have all three Hh paralogs. We find suggestions that following the WGD events,