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Sample records for muscone protects vertebral

  1. Enhancing Effect of Borneol and Muscone on Geniposide Transport across the Human Nasal Epithelial Cell Monolayer

    PubMed Central

    Chen, Zhenzhen; Gong, Xin; Lu, Yang; Du, Shouying; Yang, Zhihui; Bai, Jie; Li, Pengyue; Wu, Huichao

    2014-01-01

    Geniposide is widely used in the treatment of cerebral ischemic stroke and cerebrovascular diseases for its anti-thrombotic and anti-inflammatory effects. Recent studies demonstrated that geniposide could be absorbed promptly and thoroughly by intranasal administration in mice and basically transported into the brain. Here, we explored its transport mechanism and the effect of borneol and muscone on its transport by human nasal epithelial cell (HNEC) monolayer. The cytotoxicity of geniposide, borneol, muscone and their combinations on HNECs was evaluated by the MTT assay. Transcellular transport of geniposide and the influence of borneol and muscone were studied using the HNEC monolayer. Immunostaining and transepithelial electrical resistance were measured to assess the integrity of the monolayer. The membrane fluidity of HNEC was evaluated by fluorescence recovery after photobleaching. Geniposide showed relatively poor absorption in the HNEC monolayer and it was not a P-gp substrate. Geniposide transport in both directions significantly increased when co-administrated with increasing concentrations of borneol and muscone. The enhancing effect of borneol and muscone on geniposide transport across the HNEC may be attributed to the significant enhancement on cell membrane fluidity, disassembly effect on tight junction integrity and the process was reversible. These results indicated that intranasal administration has good potential to treat cerebrovascular diseases. PMID:24992195

  2. Patterns of Vertebrate Diversity and Protection in Brazil.

    PubMed

    Jenkins, Clinton N; Alves, Maria Alice S; Uezu, Alexandre; Vale, Mariana M

    2015-01-01

    Most conservation decisions take place at national or finer spatial scales. Providing useful information at such decision-making scales is essential for guiding the practice of conservation. Brazil is one of the world's megadiverse countries, and consequently decisions about conservation in the country have a disproportionate impact on the survival of global biodiversity. For three groups of terrestrial vertebrates (birds, mammals, and amphibians), we examined geographic patterns of diversity and protection in Brazil, including that of endemic, small-ranged, and threatened species. To understand potential limitations of the data, we also explored how spatial bias in collection localities may influence the perceived patterns of diversity. The highest overall species richness is in the Amazon and Atlantic Forests, while the Atlantic Forest dominates in terms of country endemics and small-ranged species. Globally threatened species do not present a consistent pattern. Patterns for birds were similar to overall species richness, with higher concentrations of threatened species in the Atlantic Forest, while mammals show a more generalized pattern across the country and a high concentration in the Amazon. Few amphibians are listed as threatened, mostly in the Atlantic Forest. Data deficient mammals occur across the country, concentrating in the Amazon and southeast Atlantic Forest, and there are no data deficient birds in Brazil. In contrast, nearly a third of amphibians are data deficient, widespread across the country, but with a high concentration in the far southeast. Spatial biases in species locality data, however, possibly influence the perceived patterns of biodiversity. Regions with low sampling density need more biological studies, as do the many data deficient species. All biomes except the Amazon have less than 3% of their area under full protection. Reassuringly though, rates of protection do correlate with higher biodiversity, including higher levels of

  3. Patterns of Vertebrate Diversity and Protection in Brazil

    PubMed Central

    Jenkins, Clinton N.; Alves, Maria Alice S.; Uezu, Alexandre; Vale, Mariana M.

    2015-01-01

    Most conservation decisions take place at national or finer spatial scales. Providing useful information at such decision-making scales is essential for guiding the practice of conservation. Brazil is one of the world’s megadiverse countries, and consequently decisions about conservation in the country have a disproportionate impact on the survival of global biodiversity. For three groups of terrestrial vertebrates (birds, mammals, and amphibians), we examined geographic patterns of diversity and protection in Brazil, including that of endemic, small-ranged, and threatened species. To understand potential limitations of the data, we also explored how spatial bias in collection localities may influence the perceived patterns of diversity. The highest overall species richness is in the Amazon and Atlantic Forests, while the Atlantic Forest dominates in terms of country endemics and small-ranged species. Globally threatened species do not present a consistent pattern. Patterns for birds were similar to overall species richness, with higher concentrations of threatened species in the Atlantic Forest, while mammals show a more generalized pattern across the country and a high concentration in the Amazon. Few amphibians are listed as threatened, mostly in the Atlantic Forest. Data deficient mammals occur across the country, concentrating in the Amazon and southeast Atlantic Forest, and there are no data deficient birds in Brazil. In contrast, nearly a third of amphibians are data deficient, widespread across the country, but with a high concentration in the far southeast. Spatial biases in species locality data, however, possibly influence the perceived patterns of biodiversity. Regions with low sampling density need more biological studies, as do the many data deficient species. All biomes except the Amazon have less than 3% of their area under full protection. Reassuringly though, rates of protection do correlate with higher biodiversity, including higher levels of

  4. Psychological effects of musky compounds: comparison of androstadienone with androstenol and muscone.

    PubMed

    Jacob, Suma; Garcia, Sheila; Hayreh, Davinder; McClintock, Martha K

    2002-11-01

    Previously, we have shown that delta4,16-androstadien-3-one modulates psychological state, reducing negative mood and increasing positive mood (Jacob and McClintock, 2000; Jacob et al., 2001a). In order to determine whether similar musky compounds also produce these effects, we compared the effects of androstadienone to those of androstenol and muscone, measuring the psychological states of 37 participants. Androstenol and muscone were chosen because they too have a musky odor at high concentrations, while androstenol is a steroid like androstadienone and muscone is not. In a controlled laboratory setting, we conducted a double-blind, within-subject, repeated-measures experiment counterbalanced for order of presentation. Under each participant's nose, a nanomolar amount of each compound was presented, masked by clove oil to minimize perceptible olfactory differences. Participants completed a baseline psychological battery and twice again at 25-min intervals after exposure. Androstadienone's effects on psychological state were unique in comparison with those of androstenol and with muscone. Exposure through passive inhalation, rather than dermal contact, was sufficient for these effects. Although this is additional evidence that androstadienone may be a pheromone, it is yet to be determined whether humans exude concentrations into the air adequate for social communication or process this chemical information within natural social contexts. PMID:12460587

  5. Self-Assembled Thermoresponsive Nanogels Prepared by Reverse Micelle → Positive Micelle Method for Ophthalmic Delivery of Muscone, a Poorly Water-Soluble Drug.

    PubMed

    Wang, Guohua; Nie, Qixia; Zang, Chen; Zhang, Baoxian; Zhu, Qiong; Luo, Gan; Wang, Shuang

    2016-09-01

    This study aimed to design a nanocarrier ophthalmic delivery system of muscone, a poorly water-soluble drug. The muscone thermoresponsive nanogels were self-assembled by reverse micelle → positive micelle method. Muscone was demonstrated to have uniform narrow particle size distribution in nanogel by the dynamic light scattering test. The developed nanocomposite hydrogel had a high muscone loading, and the rheology results showed that the phase transition temperature was 34.05°C. Thixotropy test indicated that the nanogel was able to resist the blinking of eyes because of the thixotropy recovery time, which is <5 s. Compared with muscone eye drops, muscone nanogels showed longer retention time on the corneal surface using fluorescent labeling technology and produced a 3.4-fold increase in apparent permeability coefficients (Papp). Draize testing showed that the developed nanogel caused no eye irritation. In vivo pharmacokinetic study indicated that the nanogel could significantly increase the bioavailability of muscone after administration compared with eye drops. These results indicate that self-assembled thermoresponsive nanogel prepared by reverse micelle → positive micelle method has potential for the ophthalmic delivery of poorly water-soluble drugs. PMID:27041413

  6. Spatial mismatch of phylogenetic diversity across three vertebrate groups and protected areas in Europe

    PubMed Central

    Zupan, Laure; Cabeza, Mar; Maiorano, Luigi; Roquet, Cristina; Devictor, Vincent; Lavergne, Sébastien; Mouillot, David; Mouquet, Nicolas; Renaud, Julien; Thuiller, Wilfried

    2014-01-01

    Aim We investigate patterns of phylogenetic diversity in relation to species diversity for European birds, mammals and amphibians, to evaluate their congruence and highlight areas of particular evolutionary history. We estimate the extent to which the European network of protected areas (PAs) network retains interesting evolutionary history areas for the three groups separately and simultaneously. Location Europe Methods Phylogenetic (QEPD) and species diversity (SD) were estimated using the Rao’s quadratic entropy at 10′ resolution. We determined the regional relationship between QEPD and SD for each taxa with a spatial regression model and used the tails of the residuals (QERES) distribution to identify areas of higher and lower QEPD than predicted. Spatial congruence of biodiversity between groups was assessed with Pearson’s correlation. A simple classification scheme allowed building a convergence map where a convergent pixel equalled to a QERES value of the same sign for the 3 groups. This convergence map was overlaid to the current PAs network to estimate the level of protection in convergent pixels and compared it to a null expectation built on 1000 randomization of PAs over the landscape. Results QERES patterns across vertebrates show a strong spatial mismatch highlighting different evolutionary histories. Convergent areas represent only 2.7% of the Western Palearctic, with only 8.4% of these areas being covered by the current PAs network while a random distribution would retain 10.4% of them. QERES are unequally represented within PAs: areas with higher QEPD than predicted are better covered than expected, while low QEPD areas are undersampled. Main conclusions Patterns of diversity strongly diverge between groups of vertebrates in Europe. Although Europe has the world’s most extensive PAs network, evolutionary history of terrestrial vertebrates is unequally protected. The challenge is now to reconcile effective conservation planning with a

  7. Survey of protected terrestrial vertebrates on the Oak Ridge Reservation 1995 annual progress report

    SciTech Connect

    Vail, E.R.; Mitchell, J.M.; Webb, J.W.; King, A.L.; Hamlett, P.A.

    1995-11-01

    This progress report discusses surveys of protected terrestrial vertebrates on the Oak Ridge Reservation (ORR) from October 1994 through September 1995. These surveys are important to help avoid or minimize potential impacts of projects on the ORR to species listed as threatened, endangered, or in need of management by the US Fish and Wildlife Service and the Tennessee Wildlife Resources Agency. Currently, there are 69 species of federally or state-listed terrestrial vertebrates that may occur in Tennessee. Not all of these are expected to occur on the ORR, nor do resources permit comprehensive sampling for all of them over the entire ORR. To effectively organize sampling efforts, listed animal species that might be present were targeted using a prioritization system based on historical and recent sightings, species distributions, literature reviews, and personal communications. Sampling was conducted during the time of the year when each targeted species would most likely be encountered. Several trapping and surveying methods were used, including pitfall traps, Sherman traps, seining, artificial covers, and cave and avian surveys.

  8. Survey of protected terrestrial vertebrates on the Oak Ridge Reservation. Final report

    SciTech Connect

    Mitchell, J.M.; Vail, E.R.; Webb, J.W.; King, A.L.; Hamlett, P.A.

    1996-05-01

    Surveys of protected terrestrial vertebrates on the Oak Ridge Reservation (ORR) were conducted from October 1994 through May 1996. The surveys were undertaken to help avoid or minimize the potential impacts of projects on the ORR to species listed by the state or federal government as endangered, threatened, or in need-of-management; federal species of concern were included. Results of the survey will also assist in effectively managing the ORR. Currently, there are 69 species of federal- or state-listed terrestrial vertebrates (20 reptiles and amphibians, 20 mammals, and 29 birds) that may occur in Tennessee. Listed animal species that might be present on the ORR were targeted for survey using a prioritization system based on historical and recent sightings, known species distributions, presence of suitable habitat, literature reviews, and personal communications. Survey methods included trapping, seining, monitoring artificial covers, active searching, and avian surveys. Surveys were conducted during the time of year when each targeted species was most likely to be encountered. The report also includes ancillary information. Records are provided for nonlisted species (44 species of reptiles and amphibians, 155 species of birds, and 28 species of mammals). Categorization of survey sites into 1 or more of 19 habitat types, which are briefly described, is presented. Notes are summarized on the occurrence of threatened and endangered species on the ORR. The report also lists threatened and endangered species not found that might be located by additional surveys, recommends three survey areas for natural-area status due to wildlife value, and suggests several avenues for future work.

  9. Survey of protected terrestrial vertebrates on the Oak Ridge Reservation. Final report

    SciTech Connect

    Mitchell, J.M.; Vail, E.R.; Webb, J.W.; Evans, J.W.

    1996-07-01

    This document is the final report on surveys of protected terrestrial vertebrates on the Oak Ridge Reservation (ORR) conducted from October 1994 through May 1996. The surveys were undertaken to gain information that could help prevent or minimize the potential impacts of projects on the ORR to species listed by the state or federal government as endangered, threatened, or in need of management; federal species of concern were also included. The results of the survey will assist in the effective management of the natural resources of the ORR. Currently, there are 69 species of federal or state listed terrestrial vertebrates (20 reptiles and amphibians, 20 mammals, and 29 birds) that may occur in Tennessee. Listed animal species that might be present on the ORR were targeted for survey using a prioritization system based on historical and recent sightings, known species distributions, presence of suitable habitat, literature reviews, and personal communications. Survey methods included trapping, seining, monitoring of artificial covers, active searching, and avian surveys. Surveys were conducted during the time of year when each targeted species was most likely to be encountered. The surveys confirmed the presence of 20 threatened and endangered species on the ORR. This report also includes some ancillary information. Records are provided for nonlisted species (44 species of reptiles and amphibians, 155 species of birds, and 28 species of mammals). Categorization of survey sites into 1 or more of 19 habitat types, which are briefly described, is presented. Notes are summarized on the occurrence of threatened and endangered species on the ORR. Finally, this report also lists threatened and endangered species not found that might be located by additional surveys, recommends three survey areas for natural-area status due to wildlife value, and suggests several avenues for future work.

  10. China's endemic vertebrates sheltering under the protective umbrella of the giant panda.

    PubMed

    Li, Binbin V; Pimm, Stuart L

    2016-04-01

    The giant panda attracts disproportionate conservation resources. How well does this emphasis protect other endemic species? Detailed data on geographical ranges are not available for plants or invertebrates, so we restrict our analyses to 3 vertebrate taxa: birds, mammals, and amphibians. There are gaps in their protection, and we recommend practical actions to fill them. We identified patterns of species richness, then identified which species are endemic to China, and then which, like the panda, live in forests. After refining each species' range by its known elevational range and remaining forest habitats as determined from remote sensing, we identified the top 5% richest areas as the centers of endemism. Southern mountains, especially the eastern Hengduan Mountains, were centers for all 3 taxa. Over 96% of the panda habitat overlapped the endemic centers. Thus, investing in almost any panda habitat will benefit many other endemics. Existing panda national nature reserves cover all but one of the endemic species that overlap with the panda's distribution. Of particular interest are 14 mammal, 20 bird, and 82 amphibian species that are inadequately protected. Most of these species the International Union for Conservation of Nature currently deems threatened. But 7 mammal, 3 bird, and 20 amphibian species are currently nonthreatened, yet their geographical ranges are <20,000 km(2) after accounting for elevational restriction and remaining habitats. These species concentrate mainly in Sichuan, Yunnan, Nan Mountains, and Hainan. There is a high concentration in the east Daxiang and Xiaoxiang Mountains of Sichuan, where pandas are absent and where there are no national nature reserves. The others concentrate in Yunnan, Nan Mountains, and Hainan. Here, 10 prefectures might establish new protected areas or upgrade local nature reserves to national status. PMID:26332026

  11. Insecticidal and vertebrate toxicity associated with ethnobotanicals used as post-harvest protectants in Ghana.

    PubMed

    Belmain, S R; Neal, G E; Ray, D E; Golob, P

    2001-03-01

    Six plant species (Cassia sophera, Chamaecrista nigricans, Mitragyna inermis, Ocimum americanum, Securidaca longepedunculata and Synedrella nodiflora) traditionally used in Ghana to control insect pests of stored grain and legumes were screened in the laboratory at three concentrations (0.5, 1 and 5%, w/w) against four common storage pests (Rhyzopertha dominica, Callosobruchus maculatus, Sitophilus zeamais and Prostephanus truncatus). All the plants showed some ability to control all or some of the test insect species. Levels of efficacy varied according to test concentration with the highest concentration tested providing the best control. The S. longepedunculata plant induced the highest percent mortality and was the best at reducing emergence of the F(1) generation. The six plants were also incorporated into standard rat diet at two concentrations (1 and 5%, w/w) and fed to rats over a 6-week period to assess potential deleterious effects against vertebrates. None of the plants demonstrated any neurotoxicological or neurobehavioural effects to the rats over the course of the trial. However, S. longepedunculata and C. nigricans caused a significant reduction in rat growth rate when incorporated at 5% in the diet, induced cell hyperplasia in the liver, and reduced the mean weight of the liver and kidneys, compared to the control group of rats. Kidney pathology was affected only by the 5% concentration of S. longepedunculata which caused a reduced accumulation of alpha2mu-globulin. The implications of these results are discussed in the context of farmer usage of insecticidal plants for stored product protection. PMID:11278061

  12. Use of survey data to develop sediment criteria for protecting aquatic vertebrates in mountain streams

    EPA Science Inventory

    We examined the relationship of aquatic vertebrate taxa abundances and an index of biotic integrity (IBI) to reachwide measures of areal percent streambed surficial fines (≤ 0.06 mm) and sand and fines (≤ 2 mm), based on data collected from 557 wadeable streams in the Western Mou...

  13. Endovascular stenting of symptomatic innominate artery stenosis under distal balloon protection of the internal carotid and vertebral artery for cerebral protection: a technical case report.

    PubMed

    Sakamoto, Shigeyuki; Kiura, Yoshihiro; Kajihara, Yosuke; Mukada, Kazutoshi; Kurisu, Kaoru

    2013-02-01

    The use of cerebral protection devices in endovascular treatment for innominate artery (IA) stenosis is not well established. We describe a novel technique for cerebral protection during endovascular stenting of symptomatic IA stenosis. An 82-year-old man presented with acutely scattered brain infarction by artery-to-artery embolism due to IA stenosis. Endovascular treatment for symptomatic IA stenosis was planned to prevent recurrent attacks. Endovascular stenting for IA stenosis via the right femoral artery approach was performed under simultaneous distal balloon protection of the right internal carotid artery (ICA) and vertebral artery (VA) via the right brachial artery approach. Successful treatment of symptomatic IA stenosis was achieved with no complications. The technique with simultaneous distal balloon protection of the ICA and VA provided excellent cerebral protection in stenting of IA stenosis. PMID:23263481

  14. Fluorinated Musk Fragrances: The CF2 Group as a Conformational Bias Influencing the Odour of Civetone and (R)-Muscone.

    PubMed

    Callejo, Ricardo; Corr, Michael J; Yang, Mingyan; Wang, Mingan; Cordes, David B; Slawin, Alexandra M Z; O'Hagan, David

    2016-06-01

    The difluoromethylene (CF2 ) group has a strong tendency to adopt corner over edge locations in aliphatic macrocycles. In this study, the CF2 group has been introduced into musk relevant macrocyclic ketones. Nine civetone and five muscone analogues have been prepared by synthesis for structure and odour comparisons. X-ray studies indeed show that the CF2 groups influence ring structure and they give some insight into the preferred ring conformations, triggering a musk odour as determined in a professional perfumery environment. The historical conformational model of Bersuker and co-workers for musk fragrance generally holds, and structures that become distorted from this consensus, by the particular placement of the CF2 groups, lose their musk fragrance and become less pleasant. PMID:27149882

  15. On how much biodiversity is covered in Europe by national protected areas and by the Natura 2000 network: insights from terrestrial vertebrates.

    PubMed

    Maiorano, L; Amori, G; Montemaggiori, A; Rondinini, C; Santini, L; Saura, S; Boitani, L

    2015-08-01

    The European Union has made extensive biodiversity conservation efforts with the Habitats and Birds Directives and with the establishment of the Natura 2000 network of protected areas, one of the largest networks of conservation areas worldwide. We performed a gap analysis of the entire Natura 2000 system plus national protected areas and all terrestrial vertebrates (freshwater fish excluded). We also evaluated the level of connectivity of both systems, providing therefore a first estimate of the functionality of the Natura 2000 system as an effective network of protected areas. Together national protected areas and the Natura 2000 network covered more than one-third of the European Union. National protected areas did not offer protection to 13 total gap species (i.e., species not covered by any protected area) or to almost 300 partial gap species (i.e., species whose representation target is not met). Together the Natura 2000 network and national protected areas left 1 total gap species and 121 partial gap species unprotected. The terrestrial vertebrates listed in the Habitats and Birds Directives were relatively well covered (especially birds), and overall connectivity was improved considerably by Natura 2000 sites that act as stepping stones between national protected areas. Overall, we found that the Natura 2000 network represents at continental level an important network of protected areas that acts as a good complement to existing national protected areas. However, a number of problems remain that are mainly linked to the criteria used to list the species in the Habitats and Birds Directives. The European Commission initiated in 2014 a process aimed at assessing the importance of the Birds and Habitats Directives for biodiversity conservation. Our results contribute to this assessment and suggest the system is largely effective for terrestrial vertebrates but would benefit from further updating of the species lists and field management. PMID:25997522

  16. Vertebrate skeletogenesis.

    PubMed

    Lefebvre, Véronique; Bhattaram, Pallavi

    2010-01-01

    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 nonexperts 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 toward 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

  17. Vertebral Morphometry.

    PubMed

    Chou, Sharon H; Vokes, Tamara

    2016-01-01

    There is as yet no agreement about the criteria by which to arrive at an imaging diagnosis of a vertebral fracture. Because high-grade fractures result in alterations in vertebral shape, 1 possible avenue of diagnosis has been to quantitate changes in vertebral shape. The result has been a variety of methods for the relative and absolute measurements of vertebral dimensions. Such measurements have also lent themselves to automated computed analysis. The number of techniques reflects the absence of any consensus about the best. The semiquantitative technique proposed by Genant has become the most widely used and has served the field well for comparative purposes. Its use in higher grade fractures has been widely endorsed, if some concepts (e.g., short vertebral height-vertebrae) are at variance with lower grades of fracturing. Vertebral morphometry may be the only recourse in high volume epidemiological and interventional studies. PMID:26349790

  18. [Construction of an indicator system for evaluating the protection efficacy of national nature reserves in China: A case study on terrestrial vertebrates (excluding migratory birds)].

    PubMed

    Yan, Yu-ying; Yang, Dao-de; Deng, Jiao; Zhang, Zhi-qiang; Zhou, Xian-yan; Wang, Wei; Li, Jun-sheng

    2015-05-01

    The protection efficacy of nature reserves is a key element in achieving targets of biodiversity conservation. It is therefore very important to develop a scientific, systematic, and accurate index system for evaluating the protection efficacy of national nature reserves in China. Using methods of frequency statistics, expert consultation, analytic hierarchy process, and demonstration survey, we present a novel index system for evaluating the protection efficacy of Chinese national nature reserves for terrestrial vertebrates (excluding migratory birds) over a 10-year period. The indicator system included one target layer, two system layers, nine factor layers, and forty index layers. The system layer included ecological effectiveness evaluation (with a score of 60%) and management effectiveness evaluation (score of 40%). The ecological effectiveness evaluation was a comprehensive, dynamic evaluation of the target species, population, habitat, and ecological system. The management effectiveness evaluation was focused on the effectiveness of patrol and monitoring. The additional part aimed to analyze the impact of humans on the target species, population and nature resources of the nature reserve. This study combined the ecological effectiveness evaluation and the management effectiveness evaluation for the first time, highlighted the importance of time and space changes, distinguished the influence of natural factors from human factors, and integrated them into the evaluation results. By emphasizing quantifiable indicators, this evaluation index system could vastly assist the protection of nature reserves by improving management effectiveness, biodiversity conservation, and macroscopic decision-making. PMID:26571679

  19. Vertebrate Reproduction.

    PubMed

    Kornbluth, Sally; Fissore, Rafael

    2015-10-01

    Vertebrate reproduction requires a myriad of precisely orchestrated events-in particular, the maternal production of oocytes, the paternal production of sperm, successful fertilization, and initiation of early embryonic cell divisions. These processes are governed by a host of signaling pathways. Protein kinase and phosphatase signaling pathways involving Mos, CDK1, RSK, and PP2A regulate meiosis during maturation of the oocyte. Steroid signals-specifically testosterone-regulate spermatogenesis, as does signaling by G-protein-coupled hormone receptors. Finally, calcium signaling is essential for both sperm motility and fertilization. Altogether, this signaling symphony ensures the production of viable offspring, offering a chance of genetic immortality. PMID:26430215

  20. 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…

  1. Management of Vertebral Stenosis Complicated by Presence of Acute Thrombus

    SciTech Connect

    Canyigit, Murat; Arat, Anil Cil, Barbaros E.; Sahin, Gurdal; Turkbey, Baris; Elibol, Bulent

    2007-04-15

    A 44-year-old male presented with multiple punctate acute infarcts of the vertebrobasilar circulation and a computed tomographic angiogram showing stenosis of the right vertebral origin. A digital subtraction angiogram demonstrated a new intraluminal filling defect at the origin of the stenotic vertebral artery where antegrade flow was maintained. This filling defect was accepted to be an acute thrombus of the vertebral origin, most likely due to rupture of a vulnerable plaque. The patient was treated with intravenous heparin. A control angiogram revealed dissolution of the acute thrombus under anticoagulation and the patient was treated with stenting with distal protection. Diffusion-weighted magnetic resonance imaging demonstrated no additional acute ischemic lesions. We were unable to find a similar report in the English literature documenting successful management of an acute vertebral ostial thrombus with anticoagulation. Anticoagulation might be considered prior to endovascular treatment of symptomatic vertebral stenoses complicated by the presence of acute thrombus.

  2. 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. PMID:11550762

  3. [Vertebral hydatidosis: case report].

    PubMed

    Varela, R; Santelices, J P; Cuzmar, D; Aldunate, J T; Plaza-Guzmán, N; Lizama-Calvo, P

    2015-01-01

    Hydatidosis caused by echinococcus granulosus may affect any organ in the body, with the lungs and the liver as the most commonly affected organs. Vertebral compromise resulting from echinococcus granulosus has a low prevalence and accounts for less than 1% of bone compromise. We report the case of a 50 year-old female who presented at the Trauma Service with progressive low back pain with 5 months of duration that irradiated to the right lower limb, and led to neurologic compromise of the limb. Imaging studies showed spondylodiscitis at T12-L1, confirmed by a biopsy. Treatment of this condition is both orthopedic and surgical. The recurrence rate is high, between 30 and 40%. The objective of describing this case is to propose the differential diagnosis of a vertebral mass of unknown origin and provide details as to how to manage this condition. PMID:27012085

  4. 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

  5. Building the Vertebrate Spine

    NASA Astrophysics Data System (ADS)

    Pourquié, Olivier

    2008-03-01

    The vertebrate body can be subdivided along the antero-posterior (AP) axis into repeated structures called segments. This periodic pattern is established during embryogenesis by the somitogenesis process. Somites are generated in a rhythmic fashion from the paraxial mesoderm and subsequently differentiate to give rise to the vertebrae and skeletal muscles of the body. Somite formation involves an oscillator-the segmentation clock-whose periodic signal is converted into the periodic array of somite boundaries. This clock drives the dynamic expression of cyclic genes in the presomitic mesoderm and requires Notch and Wnt signaling. Microarray studies of the mouse presomitic mesoderm transcriptome reveal that the segmentation clock drives the periodic expression of a large network of cyclic genes involved in cell signaling. Mutually exclusive activation of the Notch/FGF and Wnt pathways during each cycle suggests that coordinated regulation of these three pathways underlies the clock oscillator. In humans, mutations in the genes associated to the function of this oscillator such as Dll3 or Lunatic Fringe result in abnormal segmentation of the vertebral column such as those seen in congenital scoliosis. Whereas the segmentation clock is thought to set the pace of vertebrate segmentation, the translation of this pulsation into the reiterated arrangement of segment boundaries along the AP axis involves dynamic gradients of FGF and Wnt signaling. The FGF signaling gradient is established based on an unusual mechanism involving mRNA decay which provides an efficient means to couple the spatio-temporal activation of segmentation to the posterior elongation of the embryo. Another striking aspect of somite production is the strict bilateral symmetry of the process. Retinoic acid was shown to control aspects of this coordination by buffering destabilizing effects from the embryonic left-right machinery. Defects in this embryonic program controlling vertebral symmetry might lead

  6. Mechanotransduction During Vertebrate Neurulation.

    PubMed

    Sokol, Sergei Y

    2016-01-01

    Vertebrate neural tube formation is a complex morphogenetic process, which involves hundreds of genes dynamically coordinating various behaviors in different cell populations of neural tissue. The challenge remains to determine the relative contributions of physical forces and biochemical signaling events to neural tube closure and accompanying cell fate specification. Planar cell polarity (PCP) molecules are prime candidate factors for the production of actomyosin-dependent mechanical signals necessary for morphogenesis. Conversely, physical forces may contribute to the polarized distribution of PCP proteins. Understanding mechanosensory and mechanotransducing properties of diverse molecules should help define the direction and amplitude of physical stresses that are critical for neurulation. PMID:26969989

  7. Vertebral Angiosarcoma. Case Study.

    PubMed

    Guzik, Grzegorz

    2015-01-01

    Bone angiosarcomas, especially vertebral angiosarcomas, are very rare. There are no studies based on large clinical samples in the literature, and only a few single case reports can be found. The symptoms of the disease are not specific. It is usually detected incidentally or at a late stage when pathological vertebral fractures or neurological complications occur. Diagnostic imaging and history help to recognize the tumour behind the symptoms, but do not allow accurate clinical diagnosis. The basis for a diagnosis is the histopathological examination supported by immunohistochemistry (IHC) assays. The case of a 26-year-old woman with an angiosarcoma involving the eighth thoracic vertebra we report reflects diagnostic problems adversely affecting the efficacy and accuracy of treatment offered to patients. The patient underwent three surgeries of the spine, including two biopsies. A needle biopsy did not provide sufficient information for the diagnosis. An open excisional biopsy, which at the same time temporarily reduced neurological deficits in the patient, was the only chance to obtain an accurate diagnosis. The third surgery was posterior decompression of the spinal cord due to the rapidly escalating paraparesis. It was not until 8 weeks later that the final diagnosis was established. At that time, the patient could not be qualified for any supplementary treatment. The patient died in hospital 6 months after the onset of disease. PMID:26468177

  8. The epidemiology of vertebral fractures. European Vertebral Osteoporosis Study Group.

    PubMed

    Cooper, C; O'Neill, T; Silman, A

    1993-01-01

    Vertebral fractures are recognised as a hallmark of osteoporosis, yet little is known of their epidemiology. This deficiency limits accurate characterisation of the public health importance of osteoporosis. Assessment of the impact of vertebral fractures has been hampered by the absence of formal criteria for identifying fractures on a thoracolumbar radiograph. Initial methods relying upon subjective radiological assessments have given way to morphometric measurements of vertebral heights, with deformities defined according to various algorithms. These methods have been used in a series of studies performed in Rochester, MN, to determine the incidence, outcome, and time trends of vertebral deformities. The results suggest a prevalence rate of vertebral deformity of 25.3 per 100 Rochester women aged 50 years and over (95% CI, 22.3-28.2), with an estimated incidence of 17.8 per 1,000 person-years. The incidence of clinically diagnosed vertebral fractures among women in the same population was 5.3 per 1,000 person-years, suggesting that around 30% of such deformities in women receive clinical attention. Morphometric measurement on the radiographs of women with clinically diagnosed fractures revealed that 80% had grade 2 ( > 4 SD) deformities. Comparable data on the occurrence and health impact of vertebral deformities throughout Europe are urgently required. The European Vertebral Osteoporosis Study (EVOS) is a multicentre epidemiological study that aims to address this issue. It is designed as a radiographic prevalence study in 34 European centres.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8110529

  9. Vertebral fracture classification

    NASA Astrophysics Data System (ADS)

    de Bruijne, Marleen; Pettersen, Paola C.; Tankó, László B.; Nielsen, Mads

    2007-03-01

    A novel method for classification and quantification of vertebral fractures from X-ray images is presented. Using pairwise conditional shape models trained on a set of healthy spines, the most likely unfractured shape is estimated for each of the vertebrae in the image. The difference between the true shape and the reconstructed normal shape is an indicator for the shape abnormality. A statistical classification scheme with the two shapes as features is applied to detect, classify, and grade various types of deformities. In contrast with the current (semi-)quantitative grading strategies this method takes the full shape into account, it uses a patient-specific reference by combining population-based information on biological variation in vertebra shape and vertebra interrelations, and it provides a continuous measure of deformity. Good agreement with manual classification and grading is demonstrated on 204 lateral spine radiographs with in total 89 fractures.

  10. Chemical ecology of vertebrate carrion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  11. Molecular Evolutionary Analysis of β-Defensin Peptides in Vertebrates

    PubMed Central

    Tu, Jianbo; Li, Diyan; Li, Qingqing; Zhang, Long; Zhu, Qing; Gaur, Uma; Fan, Xiaolan; Xu, Huailiang; Yao, Yongfang; Zhao, Xiaoling; Yang, Mingyao

    2015-01-01

    Vertebrate β-defensins comprise an important family of antimicrobial peptides that protect organisms from a diverse spectrum of bacteria, viruses, fungi, and protozoan parasites. Previous studies have shown a marked variation in the number of β-defensins among species, but the underlying reason is unclear. To address this question, we performed comprehensive computational searches to study the intact β-defensin genes from 29 vertebrates. Phylogenetic analysis of the β-defensin genes in vertebrates identified frequent changes in the number of β-defensin genes and multiple species-specific gene gains and losses that have been occurring throughout the evolution of vertebrates. The number of intact β-defensin genes varied from 1 in the western clawed frog to 20 in cattle, with numerous expansions and contractions of the gene family throughout vertebrates, especially among tetrapods. The β-defensin gene number in a species is relevant to the ever-changing microbial challenges from the environment that they inhabit. Selection pressure analysis shows there exist three amino acid sites under significant positive selection. Protein structural characteristics analysis suggests that structural diversity determines the diverse functions of β-defensins. Our study provides a new perspective on the relationships among vertebrate β-defensin gene repertoires and different survival circumstances, which helps explain how β-defensins have evolved. PMID:26056425

  12. Molecular Evolutionary Analysis of β-Defensin Peptides in Vertebrates.

    PubMed

    Tu, Jianbo; Li, Diyan; Li, Qingqing; Zhang, Long; Zhu, Qing; Gaur, Uma; Fan, Xiaolan; Xu, Huailiang; Yao, Yongfang; Zhao, Xiaoling; Yang, Mingyao

    2015-01-01

    Vertebrate β-defensins comprise an important family of antimicrobial peptides that protect organisms from a diverse spectrum of bacteria, viruses, fungi, and protozoan parasites. Previous studies have shown a marked variation in the number of β-defensins among species, but the underlying reason is unclear. To address this question, we performed comprehensive computational searches to study the intact β-defensin genes from 29 vertebrates. Phylogenetic analysis of the β-defensin genes in vertebrates identified frequent changes in the number of β-defensin genes and multiple species-specific gene gains and losses that have been occurring throughout the evolution of vertebrates. The number of intact β-defensin genes varied from 1 in the western clawed frog to 20 in cattle, with numerous expansions and contractions of the gene family throughout vertebrates, especially among tetrapods. The β-defensin gene number in a species is relevant to the ever-changing microbial challenges from the environment that they inhabit. Selection pressure analysis shows there exist three amino acid sites under significant positive selection. Protein structural characteristics analysis suggests that structural diversity determines the diverse functions of β-defensins. Our study provides a new perspective on the relationships among vertebrate β-defensin gene repertoires and different survival circumstances, which helps explain how β-defensins have evolved. PMID:26056425

  13. Charcot Arthropathy of the Lumbosacral Spine Mimicking a Vertebral Tumor after Spinal Cord Injury

    PubMed Central

    Son, Soo-Bum; Kim, Eun-Sang; Eoh, Whan

    2013-01-01

    Charcot spinal arthropathy is a rare, progressive type of vertebral joint degeneration that occurs in the setting of any preexisting condition characterized by decreased afferent innervation to the extent that normal protective joint sensation in the vertebral column is impaired. The authors report on a case of Charcot arthropathy of the lower lumbar spine mimicking a spinal tumor following cervical cord injury. PMID:24527202

  14. 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. PMID:23640588

  15. Global patterns of terrestrial vertebrate diversity and conservation.

    PubMed

    Jenkins, Clinton N; Pimm, Stuart L; Joppa, Lucas N

    2013-07-01

    Identifying priority areas for biodiversity is essential for directing conservation resources. Fundamentally, we must know where individual species live, which ones are vulnerable, where human actions threaten them, and their levels of protection. As conservation knowledge and threats change, we must reevaluate priorities. We mapped priority areas for vertebrates using newly updated data on >21,000 species of mammals, amphibians, and birds. For each taxon, we identified centers of richness for all species, small-ranged species, and threatened species listed with the International Union for the Conservation of Nature. Importantly, all analyses were at a spatial grain of 10 × 10 km, 100 times finer than previous assessments. This fine scale is a significant methodological improvement, because it brings mapping to scales comparable with regional decisions on where to place protected areas. We also mapped recent species discoveries, because they suggest where as-yet-unknown species might be living. To assess the protection of the priority areas, we calculated the percentage of priority areas within protected areas using the latest data from the World Database of Protected Areas, providing a snapshot of how well the planet's protected area system encompasses vertebrate biodiversity. Although the priority areas do have more protection than the global average, the level of protection still is insufficient given the importance of these areas for preventing vertebrate extinctions. We also found substantial differences between our identified vertebrate priorities and the leading map of global conservation priorities, the biodiversity hotspots. Our findings suggest a need to reassess the global allocation of conservation resources to reflect today's improved knowledge of biodiversity and conservation. PMID:23803854

  16. Evolution of vertebrate retinal photoreception

    PubMed Central

    Lamb, Trevor D.

    2009-01-01

    Recent findings shed light on the steps underlying the evolution of vertebrate photoreceptors and retina. Vertebrate ciliary photoreceptors are not as wholly distinct from invertebrate rhabdomeric photoreceptors as is sometimes thought. Recent information on the phylogenies of ciliary and rhabdomeric opsins has helped in constructing the likely routes followed during evolution. Clues to the factors that led the early vertebrate retina to become invaginated can be obtained by combining recent knowledge about the origin of the pathway for dark re-isomerization of retinoids with knowledge of the inability of ciliary opsins to undergo photoreversal, along with consideration of the constraints imposed under the very low light levels in the deep ocean. Investigation of the origin of cell classes in the vertebrate retina provides support for the notion that cones, rods and bipolar cells all originated from a primordial ciliary photoreceptor, whereas ganglion cells, amacrine cells and horizontal cells all originated from rhabdomeric photoreceptors. Knowledge of the molecular differences between cones and rods, together with knowledge of the scotopic signalling pathway, provides an understanding of the evolution of rods and of the rods' retinal circuitry. Accordingly, it has been possible to propose a plausible scenario for the sequence of evolutionary steps that led to the emergence of vertebrate photoreceptors and retina. PMID:19720653

  17. Medical treatment of vertebral osteoporosis.

    PubMed

    Lippuner, K

    2003-10-01

    Although osteoporosis is a systemic disease, vertebral fractures due to spinal bone loss are a frequent, sometimes early and often neglected complication of the disease, generally associated with considerable disability and pain. As osteoporotic vertebral fractures are an important predictor of future fracture risk, including at the hip, medical management is targeted at reducing fracture risk. A literature search for randomized, double-blind, prospective, controlled clinical studies addressing medical treatment possibilities of vertebral fractures in postmenopausal Caucasian women was performed on the leading medical databases. For each publication, the number of patients with at least one new vertebral fracture and the number of randomized patients by treatment arm was retrieved. The relative risk (RR) and the number needed to treat (NNT, i.e. the number of patients to be treated to avoid one radiological vertebral fracture over the duration of the study), together with the respective 95% confidence intervals (95%CI) were calculated for each study. Treatment of steroid-induced osteoporosis and treatment of osteoporosis in men were reviewed separately, based on the low number of publications available. Forty-five publications matched with the search criteria, allowing for analysis of 15 different substances tested regarding their anti-fracture efficacy at the vertebral level. Bisphosphonates, mainly alendronate and risedronate, were reported to have consistently reduced the risk of a vertebral fracture over up to 50 months of treatment in four (alendronate) and two (risedronate) publications. Raloxifene reduced vertebral fracture risk in one study over 36 months, which was confirmed by 48 months' follow-up data. Parathormone (PTH) showed a drastic reduction in vertebral fracture risk in early studies, while calcitonin may also be a treatment option to reduce fracture risk. For other substances published data are conflicting (calcitriol, fluoride) or insufficient

  18. 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…

  19. Vertebral Augmentation: State of the Art.

    PubMed

    Sebaaly, Amer; Nabhane, Linda; Issa El Khoury, Fouad; Kreichati, Gaby; El Rachkidi, Rami

    2016-04-01

    Osteoporotic vertebral compression fractures (OVF) are an increasing public health problem. Cement augmentation (vertebroplasty of kyphoplasty) helps stabilize painful OVF refractory to medical treatment. This stabilization is thought to improve pain and functional outcome. Vertebroplasty consists of injecting cement into a fractured vertebra using a percutaneous transpedicular approach. Balloon kyphoplasty uses an inflatable balloon prior to injecting the cement. Although kyphoplasty is associated with significant improvement of local kyphosis and less cement leakage, this does not result in long-term clinical and functional improvement. Moreover, vertebroplasty is favored by some due to the high cost of kyphoplasty. The injection of cement increases the stiffness of the fracture vertebrae. This can lead, in theory, to adjacent OVF. However, many studies found no increase of subsequent fracture when comparing medical treatment to cement augmentation. Kyphoplasty can have a protective effect due to restoration of sagittal balance. PMID:27114782

  20. Vertebral Augmentation: State of the Art

    PubMed Central

    Nabhane, Linda; Issa El Khoury, Fouad; Kreichati, Gaby; El Rachkidi, Rami

    2016-01-01

    Osteoporotic vertebral compression fractures (OVF) are an increasing public health problem. Cement augmentation (vertebroplasty of kyphoplasty) helps stabilize painful OVF refractory to medical treatment. This stabilization is thought to improve pain and functional outcome. Vertebroplasty consists of injecting cement into a fractured vertebra using a percutaneous transpedicular approach. Balloon kyphoplasty uses an inflatable balloon prior to injecting the cement. Although kyphoplasty is associated with significant improvement of local kyphosis and less cement leakage, this does not result in long-term clinical and functional improvement. Moreover, vertebroplasty is favored by some due to the high cost of kyphoplasty. The injection of cement increases the stiffness of the fracture vertebrae. This can lead, in theory, to adjacent OVF. However, many studies found no increase of subsequent fracture when comparing medical treatment to cement augmentation. Kyphoplasty can have a protective effect due to restoration of sagittal balance. PMID:27114782

  1. 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. PMID:26490134

  2. 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. PMID:26564847

  3. Extraneural Glioblastoma Multiforme Vertebral Metastasis.

    PubMed

    Goodwin, C Rory; Liang, Lydia; Abu-Bonsrah, Nancy; Hdeib, Alia; Elder, Benjamin D; Kosztowski, Thomas; Bettegowda, Chetan; Laterra, John; Burger, Peter; Sciubba, Daniel M

    2016-05-01

    Glioblastoma multiforme (GBM) is the most common malignant central nervous system tumor; however, extraneural metastasis is uncommon. Of those that metastasize extraneurally, metastases to the vertebral bodies represent a significant proportion. We present a review of 28 cases from the published literature of GBM metastasis to the vertebra. The mean age at presentation was 38.4 years with an average overall survival of 26 months. Patients were either asymptomatic with metastasis discovered at autopsy or presented with varying degrees of pain, weakness of the extremities, or other neurologic deficits. Of the cases that included the time to spinal metastasis, the average time was 26.4 months with a reported survival of 10 months after diagnosis of vertebral metastasis. A significant number of patients had no treatments for their spinal metastasis, although the intracranial lesions were treated extensively with surgery and/or adjuvant therapy. With increasing incremental gains in the survival of patients with GBM, clinicians will encounter patients with extracranial metastasis. As such, this review presents timely information concerning the presentation and outcomes of patients with vertebral metastasis. PMID:26704201

  4. Extraneural Glioblastoma Multiforme Vertebral Metastasis

    PubMed Central

    Goodwin, C. Rory; Liang, Lydia; Abu-Bonsrah, Nancy; Hdeib, Alia; Elder, Benjamin D.; Kosztowski, Thomas; Bettegowda, Chetan; Laterra, John; Burger, Peter; Sciubba, Daniel M.

    2016-01-01

    Glioblastoma multiforme (GBM) is the most common malignant central nervous system tumor; however, extraneural metastasis is uncommon. Of those that metastasize extraneurally, metastases to the vertebral bodies represent a significant proportion. We present a review of 28 cases from the published literature of GBM metastasis to the vertebra. The mean age at presentation was 38.4 years with an average overall survival of 26 months. Patients were either asymptomatic with metastasis discovered at autopsy or presented with varying degrees of pain, weakness of the extremities, or other neurologic deficits. Of the cases that included the time to spinal metastasis, the average time was 26.4 months with a reported survival of 10 months after diagnosis of vertebral metastasis. A significant number of patients had no treatments for their spinal metastasis, although the intracranial lesions were treated extensively with surgery and/or adjuvant therapy. With increasing incremental gains in the survival of patients with GBM, clinicians will encounter patients with extracranial metastasis. As such, this review presents timely information concerning the presentation and outcomes of patients with vertebral metastasis. PMID:26704201

  5. 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. PMID:11324019

  6. Vertebral Fractures: Clinical Importance and Management.

    PubMed

    Kendler, D L; Bauer, D C; Davison, K S; Dian, L; Hanley, D A; Harris, S T; McClung, M R; Miller, P D; Schousboe, J T; Yuen, C K; Lewiecki, E M

    2016-02-01

    Vertebral fractures are common and can result in acute and chronic pain, decreases in quality of life, and diminished lifespan. The identification of vertebral fractures is important because they are robust predictors of future fractures. The majority of vertebral fractures do not come to clinical attention. Numerous modalities exist for visualizing suspected vertebral fracture. Although differing definitions of vertebral fracture may present challenges in comparing data between different investigations, at least 1 in 5 men and women aged >50 years have one or more vertebral fractures. There is clinical guidance to target spine imaging to individuals with a high probability of vertebral fracture. Radiology reports of vertebral fracture need to clearly state that the patient has a "fracture," with further pertinent details such as the number, recency, and severity of vertebral fracture, each of which is associated with risk of future fractures. Patients with vertebral fracture should be considered for antifracture therapy. Physical and pharmacologic modalities of pain control and exercises or physiotherapy to maintain spinal movement and strength are important components in the care of vertebral fracture patients. PMID:26524708

  7. Bilateral mechanical rotational vertebral artery occlusion.

    PubMed

    Dargon, Phong T; Liang, Conrad W; Kohal, Anmol; Dogan, Aclan; Barnwell, Stanley L; Landry, Gregory J

    2013-10-01

    Rotational vertebral artery occlusion, or bow hunter's stroke, is reversible, positional symptomatic vertebrobasilar ischemia. The typical mechanism of action is obstruction of a dominant vertebral artery with contralateral head rotation in the setting of baseline ipsilateral vertebral artery stenosis or occlusion. Here we present a rare case of mechanical occlusion of bilateral patent vertebral arteries manifesting as near syncope with rightward head rotation. Diagnostic cerebral angiography showed dynamic right C5 vertebral occlusion and left C2 vertebral occlusion. The patient underwent right C4/5 transverse process decompression. Postoperative angiogram showed patent flow through the right vertebral artery in neutral position and with head turn with resultant resolution of symptoms. PMID:23465174

  8. Evolution of the new vertebrate head by co-option of an ancient chordate skeletal tissue.

    PubMed

    Jandzik, David; Garnett, Aaron T; Square, Tyler A; Cattell, Maria V; Yu, Jr-Kai; Medeiros, Daniel M

    2015-02-26

    A defining feature of vertebrates (craniates) is a pronounced head that is supported and protected by a robust cellular endoskeleton. In the first vertebrates, this skeleton probably consisted of collagenous cellular cartilage, which forms the embryonic skeleton of all vertebrates and the adult skeleton of modern jawless and cartilaginous fish. In the head, most cellular cartilage is derived from a migratory cell population called the neural crest, which arises from the edges of the central nervous system. Because collagenous cellular cartilage and neural crest cells have not been described in invertebrates, the appearance of cellular cartilage derived from neural crest cells is considered a turning point in vertebrate evolution. Here we show that a tissue with many of the defining features of vertebrate cellular cartilage transiently forms in the larvae of the invertebrate chordate Branchiostoma floridae (Florida amphioxus). We also present evidence that during evolution, a key regulator of vertebrate cartilage development, SoxE, gained new cis-regulatory sequences that subsequently directed its novel expression in neural crest cells. Together, these results suggest that the origin of the vertebrate head skeleton did not depend on the evolution of a new skeletal tissue, as is commonly thought, but on the spread of this tissue throughout the head. We further propose that the evolution of cis-regulatory elements near an ancient regulator of cartilage differentiation was a major factor in the evolution of the vertebrate head skeleton. PMID:25487155

  9. The Vertebral Fracture Cascade: Etiology and Clinical Implications.

    PubMed

    Broy, Susan B

    2016-01-01

    A vertebral fracture is a marker of bone fragility and is associated with a downward spiral of recurrent fractures known as the vertebral fracture cascade. Etiology of this unfortunate cascade includes bone and muscle loss from immobility, changes in spinal mechanics causing increased loading on adjacent vertebrae, and the development of an increased thoracic kyphosis (hyperkyphosis [HK]). Degenerative disc disease, common in osteoporotic patients, can also cause HK. HK of any etiology has been associated with decreased thoracic extensor muscle strength, unstable gait, increased body sway, decreased physical and pulmonary functions, chronic pain, and increased spinal loads contributing to the vertebral fracture cascade. Preventing this downward spiral requires a multidisciplinary approach that includes early identification, consideration of pharmacologic treatment, early mobilization of the fracture patient, appropriate exercise, and back protection. Exercise should include weight-bearing and muscle-strengthening activities, but caution is needed to avoid undue stress on the back. Physical therapy can be particularly helpful by teaching the patient how to safely perform daily activities and can assist the patient in establishing a safe exercise program that avoids flexion but promotes back extension and weight-bearing activities. Hopefully, these measures will decrease pain, prevent falls, improve posture, prevent additional bone and muscle loss, and potentially abort the devastating downward spiral of the vertebral fracture cascade. PMID:26363627

  10. Variance in the treatment of vertebral haemangiomas.

    PubMed

    Rawat, Sheh; Nangia, S; Ezhilalan, R B; Bansal, A K; Ghosh, D

    2007-01-01

    Vertebral haemangiomas constitute an infrequently encounterd entity in clinical practice. Although x-ray, computerised tomography scan and magnetic resonance Imaging scan provide a pathognomic picture confirming the diagnosis of vertebral haemangiomas, angiography constitutes an important tool for diagnosis and helps in deciding and execution of treatment. Various treatment modalities like surgery, radiotherapy, pre-operative embolisation, percutaneous vertebroplasty and intralesional ethanol have been discussed in the setting of asymptomatic vertebral haemangiomas to those presenting with features of cord compression. PMID:17802977

  11. 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. PMID:27053733

  12. General management of vertebral fractures.

    PubMed

    Rapado, A

    1996-03-01

    Vertebral fractures cause pain and disability. Four concepts should guide their comprehensive management: treat the patient, not the skeleton; use a multidisciplinary approach; engage the patient and his or her family in the treatment; and provide appropriate goals, education, encouragement, and support. The goals include procuring bone mass and preventing injury: back support, physical therapy, occupational therapy, psychosocial support, and prevention of falls. Initial treatment includes bed rest, pain management with local and systemic analgesia, bracing to improve comfort, and patient reassurance. Long-term management includes spinal stretching exercises and continuing ordinary activities within limits permitted by pain. A back school program is an effective addition to conventional concepts using physiotherapy exclusively. In certain selected patients, the indication for operative treatment of vertebral fracture depends on the additional injury, and extent and characteristics of cord compression; stability of the fracture; and the amount of deformity. Vertebroplasty can be effective in the control of pain and in obtaining stability of the spine. PMID:8777087

  13. Centrosome positioning in vertebrate development

    PubMed Central

    Tang, Nan; Marshall, Wallace F.

    2012-01-01

    Summary The centrosome, a major organizer of microtubules, has important functions in regulating cell shape, polarity, cilia formation and intracellular transport as well as the position of cellular structures, including the mitotic spindle. By means of these activities, centrosomes have important roles during animal development by regulating polarized cell behaviors, such as cell migration or neurite outgrowth, as well as mitotic spindle orientation. In recent years, the pace of discovery regarding the structure and composition of centrosomes has continuously accelerated. At the same time, functional studies have revealed the importance of centrosomes in controlling both morphogenesis and cell fate decision during tissue and organ development. Here, we review examples of centrosome and centriole positioning with a particular emphasis on vertebrate developmental systems, and discuss the roles of centrosome positioning, the cues that determine positioning and the mechanisms by which centrosomes respond to these cues. The studies reviewed here suggest that centrosome functions extend to the development of tissues and organs in vertebrates. PMID:23277534

  14. 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

  15. Opportunities and costs for preventing vertebrate extinctions.

    PubMed

    Conde, Dalia A; Colchero, Fernando; Güneralp, Burak; Gusset, Markus; Skolnik, Ben; Parr, Michael; Byers, Onnie; Johnson, Kevin; Young, Glyn; Flesness, Nate; Possingham, Hugh; Fa, John E

    2015-03-16

    Despite an increase in policy and management responses to the global biodiversity crisis, implementation of the 20 Aichi Biodiversity Targets still shows insufficient progress [1]. These targets, strategic goals defined by the United Nations Convention on Biological Diversity (CBD), address major causes of biodiversity loss in part by establishing protected areas (Target 11) and preventing species extinctions (Target 12). To achieve this, increased interventions will be required for a large number of sites and species. The Alliance for Zero Extinction (AZE) [2], a consortium of conservation-oriented organisations that aims to protect Critically Endangered and Endangered species restricted to single sites, has identified 920 species of mammals, birds, amphibians, reptiles, conifers and reef-building corals in 588 'trigger' sites [3]. These are arguably the most irreplaceable category of important biodiversity conservation sites. Protected area coverage of AZE sites is a key indicator of progress towards Target 11 [1]. Moreover, effective conservation of AZE sites is essential to achieve Target 12, as the loss of any of these sites would certainly result in the global extinction of at least one species [2]. However, averting human-induced species extinctions within AZE sites requires enhanced planning tools to increase the chances of success [3]. Here, we assess the potential for ensuring the long-term conservation of AZE vertebrate species (157 mammals, 165 birds, 17 reptiles and 502 amphibians) by calculating a conservation opportunity index (COI) for each species. The COI encompasses a set of measurable indicators that quantify the possibility of achieving successful conservation of a species in its natural habitat (COIh) and by establishing insurance populations in zoos (COIc). PMID:25784036

  16. Estrogenic modulation of auditory processing: a vertebrate comparison

    PubMed Central

    Caras, Melissa L.

    2013-01-01

    Sex-steroid hormones are well-known regulators of vocal motor behavior in several organisms. A large body of evidence now indicates that these same hormones modulate processing at multiple levels of the ascending auditory pathway. The goal of this review is to provide a comparative analysis of the role of estrogens in vertebrate auditory function. Four major conclusions can be drawn from the literature: First, estrogens may influence the development of the mammalian auditory system. Second, estrogenic signaling protects the mammalian auditory system from noise- and age-related damage. Third, estrogens optimize auditory processing during periods of reproductive readiness in multiple vertebrate lineages. Finally, brain-derived estrogens can act locally to enhance auditory response properties in at least one avian species. This comparative examination may lead to a better appreciation of the role of estrogens in the processing of natural vocalizations and may provide useful insights toward alleviating auditory dysfunctions emanating from hormonal imbalances. PMID:23911849

  17. 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. PMID:25968309

  18. Problems with six-point vertebral morphometry

    NASA Astrophysics Data System (ADS)

    Gardner, Jill C.; Yaffe, Laurence G.; Johansen, Jennifer M.; von Ingersleben, Gabriel; Chestnut, Charles H., III

    1998-06-01

    In this study we have examined errors in measurements of vertebral heights and vertebral area resulting from spin rotation and projection effects in x-ray images. Measurement errors were evaluated with phantom images, and simulated rotations of a 3D spine model. An active contour model (snake) was used for measurements of vertebral area. The model contained two pressure parameters which were needed to obtain good fits of the snake to upper and lower edges (endplates) of rotated vertebral bodies. Details of the snake model are included in this report. The results of this study indicate that six point vertebral morphometry can result to significant measurement errors, representing an overestimation of vertebral height and area, in cases showing projection effects and concealed endplate contours. In serial studies, such errors could produce the erroneous appearance of `growing' vertebral bodies. One can improve the accuracy of the morphometric analysis by using additional fiducial points placed on corresponding endplate contours. Additional useful information on fracture and vertebral deformity can be obtained by accurately tracking edge contours, using an active contour model, or comparable techniques.

  19. [Vertebral changes in histiocytosis x (author's transl)].

    PubMed

    Greinacher, I; Gutjahr, P

    1978-06-01

    Manifestations of histiocytosis X in the vertebral column occurred in 3 of 15 children. Pathological alterations showed a marked variability. Especially a vertebra plana should be considered as eosinophilic granuloma, until another cause is proven. Bone scans were positive in all three cases. Even in most severe cases with vertebral destruction neurological abnormalities were absent. PMID:308238

  20. 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

  1. 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. PMID:26316746

  2. 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

  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. Vertebrate eye development as modeled in Drosophila.

    PubMed

    Wawersik, S; Maas, R L

    2000-04-12

    Pax6, a member of the paired-box family of transcription factors, is critical for oculogenesis in both vertebrates and insects. Identification of potential vertebrate Pax6 targets has been guided by studies in Drosophila, where the Pax6 homologs eyeless ( ey ) and twin of eyeless ( toy ) function within a network of genes that synergistically pattern the developing fly eye. These targets, which share homology with the fly genes sine oculis, eyes absent and dachshund, exist in mice and humans as the Six, Eya and Dach gene families. Members of these gene families are present in the developing vertebrate eye, and preliminary studies suggest that they may function in a network analogous to that in the fly. Thus, despite radically different architecture, a similar molecular scaffold underlies both vertebrate and fly eye patterning, suggesting that the considerable power of Drosophila genetics can be harnessed to study mammalian ocular development. PMID:10767315

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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. PMID:22640621

  10. 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. PMID:26878338

  11. [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. PMID:11381807

  12. 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

  13. Vertebral artery occlusion and oral contraceptives.

    PubMed Central

    Ask-Upmark, E; Bickerstaff, E R

    1976-01-01

    If vertebral artery occlusion occurs in degenerative arterial disease it is almost invariably left-sided, but in vertebral artery deficiency syndromes associated with oral contraceptives a striking preponderance of right-sided involvement has been shown. This observation adds support to the view that causes other than changes in the wall of the vessel at the site of occlusion must be sought as an explanation of the occlusion. PMID:1252812

  14. 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.

  15. 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

  16. Cilia in vertebrate development and disease

    PubMed Central

    Oh, Edwin C.; Katsanis, Nicholas

    2012-01-01

    Through the combined study of model organisms, cell biology, cell signaling and medical genetics we have significantly increased our understanding of the structure and functions of the vertebrate cilium. This ancient organelle has now emerged as a crucial component of certain signaling and sensory perception pathways in both developmental and homeostatic contexts. Here, we provide a snapshot of the structure, function and distribution of the vertebrate cilium and of the pathologies that are associated with its dysfunction. PMID:22223675

  17. 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

  18. Risk factors for vertebral deformities in men: relationship to number of vertebral deformities. European Vertebral Osteoporosis Study Group.

    PubMed

    Ismail, A A; O'Neill, T W; Cooper, C; Silman, A J

    2000-02-01

    Recent epidemiological studies suggest a similar overall prevalence of vertebral deformity in men to that in women, though the influence of increasing age on the prevalence of vertebral deformity is less marked in men. However, most affected men have only a single or two vertebral deformities, which may be unrelated to osteoporosis. The aim of this study was to examine the role of risk factors, previously demonstrated to be associated with vertebral osteoporosis in females, in men with single/dual deformities compared to those with multiple deformities. Age stratified random samples of men aged 50 years and over were recruited from population registers in 30 European centers as part of the European Vertebral Osteoporosis Study (EVOS). Subjects had a lateral spinal radiograph and the presence of vertebral deformity was determined using the McCloskey algorithm. Lifestyle and other risk factor data were obtained from an interviewer-administered questionnaire. In all 6937 men with a mean age of 64.4 (SD = 8.5) years were studied of whom 738 (10.6%) subjects had one or two deformities, and 109 (1.6%) subjects had three or more deformities. There was a marked increase in the prevalence of multiple vertebral deformities with increasing age, but only a modest effect of age on the prevalence of single deformities. Associations between various risk factors for osteoporosis and vertebral deformity were analyzed separately in men with single/dual vertebral deformity from those with three or more deformities using logistic regression. After adjustment for age, there were statistically significant associations between the following risk factors and multiple deformities: previous hip fracture (odds ratio [OR] 10.5), lack of regular physical activity (OR 2.9), low body mass (OR 2.5), and previous steroid use (OR 2.3). By contrast, there were only weak associations with these same variables in males with single/dual deformities and, apart from poor self-reported general health, all

  19. 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

  20. Expression patterns and adaptive functional diversity of vertebrate myoglobins.

    PubMed

    Helbo, Signe; Weber, Roy E; Fago, Angela

    2013-09-01

    Recent years have witnessed a new round of research on one of the most studied proteins - myoglobin (Mb), the oxygen (O2) carrier of skeletal and heart muscle. Two major discoveries have stimulated research in this field: 1) that Mb has additional protecting functions, such as the regulation of in vivo levels of the signaling molecule nitric oxide (NO) by scavenging and generating NO during normoxia and hypoxia, respectively; and 2) that Mb in vertebrates (particularly fish) is expressed as tissue-specific isoforms in other tissues than heart and skeletal muscle, such as vessel endothelium, liver and brain, as found in cyprinid fish. Furthermore, Mb has also been found to protect against oxidative stress after hypoxia and reoxygenation and to undergo allosteric, O2-linked S-nitrosation, as in rainbow trout. Overall, the emerging evidence, particularly from fish species, indicates that Mb fulfills a broader array of physiological functions in a wider range of different tissues than hitherto appreciated. This new knowledge helps to better understand how variations in Mb structure and function may correlate with differences in animals' lifestyles and hypoxia-tolerance. This review integrates old and new results on Mb expression patterns and functional properties amongst vertebrates and discusses how these may relate to adaptive variations in different species. This article is part of a special issue entitled: Oxygen Binding and Sensing Proteins. PMID:23388387

  1. Developmental mechanisms of vertebrate limb evolution.

    PubMed

    Cohn, M J

    2001-01-01

    Over the past few years, our understanding of the evolution of limbs has been improved by important new discoveries in the fossil record. Additionally, rapid progress has been made in identifying the molecular basis of vertebrate limb development. It is now possible to integrate these two areas of research in order to identify the molecular developmental mechanisms underlying the evolution of paired appendages in vertebrates. After the origin of paired appendages, several vertebrate lineages reduced or eliminated fins and limbs and returned to the limbless condition. Examples include eels, caecilians, snakes, slow worms and several marine mammals. Analyses of fossil and extant vertebrates show that evolution of limblessness frequently occurred together with elongation of the trunk and loss of clear morphological boundaries in the vertebral column. This may be suggestive of a common developmental mechanism linking these two processes. We have addressed this question by analysing python embryonic development at tissue, cellular and molecular levels, and we have identified a developmental mechanism which may account for evolution of limb loss in these animals. PMID:11277086

  2. 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

  3. [Amphioxus: how to become a vertebrate].

    PubMed

    Bertrand, Stéphanie; Camasses, Alain; Escriva, Hector

    2007-01-01

    Evo-devo is a young disciplin, which aims to explain the morphological evolution of organisms through developmental mechanisms and genes networks. A major question within this discipline is the origin of vertebrates. It seems now admitted that vertebrates derive from an invertebrate chordate ancestor. Several models among living chordate representatives are used today to answer this question. The small world of evo-evo interested in the emergence of vertebrates is ebullient about the advent of several totally sequenced genomes allowing comparative analyses to become evermore reliable. Furthermore "non classical" models are developed which can be submitted to refined developmental analysis. One of these is amphioxus (genus Branchyostoma), "a peaceful anchory fillet to illuminate chordate evolution" (Garcia-Fernandez, 2006a, b). The features of this model are described in this review. PMID:17762824

  4. 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

  5. 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. PMID:23580532

  6. 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.

  7. 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

  8. Pediatric congenital vertebral artery arteriovenous malformation.

    PubMed

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

    2003-05-01

    Vertebral arteriovenous fistulas are rare in children and the congenital form has been seldom reported in the literature. Prior to using endovascular therapy techniques, only surgery was the main treatment. The most common endovascular treatment is through the use of detachable balloons. This report describes the clinical and radiological findings of a congenital vertebral artery fistula in a 20-month-old child. Balloons could not be safely employed; therefore, embolization was performed with Guglielmi detachable microcoils. We review the history and treatment of these lesions, their clinical presentation, and imaging features, including their outcome, with particular attention to the pediatric population. PMID:12695869

  9. 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

  10. Transposon-mediated Genome Manipulations in Vertebrates

    PubMed Central

    Ivics, Zoltán; Li, Meng Amy; Mátés, Lajos; Boeke, Jef D.; Bradley, Allan; Izsvák, Zsuzsanna

    2010-01-01

    Transposable elements are segments of DNA with the unique ability to move about in the genome. This inherent feature can be exploited to harness these elements as gene vectors for diverse genome manipulations. Transposon-based genetic strategies have been established in vertebrate species over the last decade, and current progress in this field indicates that transposable elements will serve as indispensable tools in the genetic toolkit of vertebrate models. In particular, transposons can be applied as vectors for somatic and germline transgenesis, and as insertional mutagens in both loss-of-function and gain-of-function forward mutagenesis screens. The major advantage of using transposons as genetic tools is that they facilitate analysis of gene function in an easy, controlled and scalable manner. Transposon-based technologies are beginning to be exploited to link sequence information to gene functions in vertebrate models. In this article, we provide an overview of transposon-based methods used in vertebrate model organisms, and highlight the most important considerations concerning genetic applications of the transposon systems. PMID:19478801

  11. 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.

  12. Vertebral osteomyelitis combined streptococcal viridans endocarditis.

    PubMed

    Lee, Kuo-Chen; Tsai, Yi-Ting; Lin, Chih-Yuan; Tsai, Chien-Sung

    2003-01-01

    Endocarditis may be difficult to diagnose in patients with osteomyelitis in an early stage because they usually are treated for fever, bone pain and stiffness in the outpatient department. Herein we report an uncommon patient who developed severe lower back pain sustained for 2 months, and streptococcal viridans infected vertebral osteomyelitis combined endocarditis were diagnosed and cured. PMID:12493523

  13. 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…

  14. Vertebral Osteomyelitis Caused by Helicobacter cinaedi

    PubMed Central

    Yoshizaki, Aisa; Takegawa, Hiroshi; Doi, Asako; Mizuno, Yasushi

    2015-01-01

    Helicobacter cinaedi causes bacteremia, cellulitis, and gastroenteritis. We report the first case of vertebral osteomyelitis caused by H. cinaedi in an elderly man with low back pain and fever. The pathogen was detected in blood and lumbar disc, and the infection was successfully treated with oral doxycycline for 11 weeks. PMID:26109448

  15. 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

  16. 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. PMID:27386723

  17. 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…

  18. A differential staining technique for vertebrate histology.

    PubMed

    Bhattacharyya, T K

    1979-03-01

    A staining method is described for studying micro-anatomy of different vertebrate tissues in the light microscope. A staining sequence of celestin blue--erythrosin--orange G--fast green with mordanting in phosphomolybdic acid yields a satisfactory differentiation and fine colour contrast in various tissues. The efficacy of the method was tested on different avian and mammalian tissues. PMID:86938

  19. 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.…

  20. De novo synthesis of a sunscreen compound in vertebrates.

    PubMed

    Osborn, Andrew R; Almabruk, Khaled H; Holzwarth, Garrett; Asamizu, Shumpei; LaDu, Jane; Kean, Kelsey M; Karplus, P Andrew; Tanguay, Robert L; Bakalinsky, Alan T; Mahmud, Taifo

    2015-01-01

    Ultraviolet-protective compounds, such as mycosporine-like amino acids (MAAs) and related gadusols produced by some bacteria, fungi, algae, and marine invertebrates, are critical for the survival of reef-building corals and other marine organisms exposed to high-solar irradiance. These compounds have also been found in marine fish, where their accumulation is thought to be of dietary or symbiont origin. In this study, we report the unexpected discovery that fish can synthesize gadusol de novo and that the analogous pathways are also present in amphibians, reptiles, and birds. Furthermore, we demonstrate that engineered yeast containing the fish genes can produce and secrete gadusol. The discovery of the gadusol pathway in vertebrates provides a platform for understanding its role in these animals, and the possibility of engineering yeast to efficiently produce a natural sunscreen and antioxidant presents an avenue for its large-scale production for possible use in pharmaceuticals and cosmetics. PMID:25965179

  1. Determination of vertebral pose in 3D by minimization of vertebral asymmetry

    NASA Astrophysics Data System (ADS)

    Vrtovec, Tomaž; Pernuš, Franjo; Likar, Boštjan

    2011-03-01

    The vertebral pose in three dimensions (3D) may provide valuable information for quantitative clinical measurements or aid the initialization of image analysis techniques. We propose a method for automated determination of the vertebral pose in 3D that, in an iterative registration scheme, estimates the position and rotation of the vertebral coordinate system in 3D images. By searching for the hypothetical points, which are located where the boundaries of anatomical structures would have maximal symmetrical correspondences when mirrored over the vertebral planes, the asymmetry of vertebral anatomical structures is minimized. The method was evaluated on 14 normal and 14 scoliotic vertebrae in images acquired by computed tomography (CT). For each vertebra, 1000 randomly initialized experiments were performed. The results show that the vertebral pose can be successfully determined in 3D with mean accuracy of 0.5mm and 0.6° and mean precision of 0.17mm and 0.17. according to the 3D position and 3D rotation, respectively.

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

    PubMed

    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

  3. 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

  4. 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. PMID:24369014

  5. Intra-arterial Onyx Embolization of Vertebral Body Lesions

    PubMed Central

    Sedora-Roman, Neda I.; Reddy, Arra Suresh; Ogilvy, Christopher S.; Thomas, Ajith J.

    2013-01-01

    While Onyx embolization of cerebrospinal arteriovenous shunts is well-established, clinical researchers continue to broaden applications to other vascular lesions of the neuraxis. This report illustrates the application of Onyx (eV3, Plymouth, MN) embolization to vertebral body lesions, specifically, a vertebral hemangioma and renal cell carcinoma vertebral body metastatic lesion. PMID:24729960

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

    PubMed Central

    2016-01-01

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

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

    PubMed Central

    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

  8. Dynamic epithelia of the developing vertebrate face

    PubMed Central

    Choe, Chong Pyo; Crump, J. Gage

    2015-01-01

    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. PMID:25748249

  9. Clinical Management of Vertebral Compression Fractures.

    PubMed

    Miller, Paul D

    2016-01-01

    Vertebral compression fractures (VCF's) are the most common form of osteoporotic fractures. Whether symptomatic or asymptomatic, they both represent a high risk for not only vertebral but also nonvertebral fractures in untreated populations. This high risk of future fracture after a VCF is independent of the T-score because bone strength is a combination of bone mineral density and bone quality. VCFs are the single greatest risk for future fractures at all other skeletal sites in untreated populations, including hip fractures. They are often unrecognized despite their exceptionally high prevalence in all genders and most ethnic groups as age increases. This article highlights some of the key messages about VCF's, and how assessment for their presence and then management will reduce the risk of all osteoporotic fractures. PMID:26439186

  10. 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.

  11. Turning Heads: Development of Vertebrate Branchiomotor Neurons

    PubMed Central

    Chandrasekhar, Anand

    2007-01-01

    The cranial motor neurons innervate muscles that control eye, jaw, and facial movements of the vertebrate head and parasympathetic neurons that innervate certain glands and organs. These efferent neurons develop at characteristic locations in the brainstem, and their axons exit the neural tube in well-defined trajectories to innervate target tissues. This review is focused on a subset of cranial motor neurons called the branchiomotor neurons, which innervate muscles derived from the branchial (pharyngeal) arches. First, the organization of the branchiomotor pathways in zebrafish, chick, and mouse embryos will be compared, and the underlying axon guidance mechanisms will be addressed. Next, the molecular mechanisms that generate branchiomotor neurons and specify their identities will be discussed. Finally, the caudally directed or tangential migration of facial branchiomotor neurons will be examined. Given the advances in the characterization and analysis of vertebrate genomes, we can expect rapid progress in elucidating the cellular and molecular mechanisms underlying the development of these vital neuronal networks. PMID:14699587

  12. 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.

  13. [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. PMID:24598790

  14. Vertebral osteomyelitis: disk hypodensity on CT

    SciTech Connect

    Larde, D.; Mathieu, D.; Frija, J.; Gaston, A.; Vasile, N.

    1982-11-01

    The importance and role of computed tomography (CT) are discussed on the basis of 36 cases of vertebral osteomyelitis. The bone images themselves, the detection of lumbar disk hypodensity, and the exploration of soft paraspinal regions in the search for an abscess are factors that contribute to the superiority of this method in difficult cases. In cases where the diagnosis is already known, CT offers an excellent method to assess the extent of the lesions. Its accuracy, coupled with its rapidity and noninvasive nature, affects the role of conventional tomography, a method that is incomplete and involves higher radiation doses. CT offers an excellent method for follow-up after treatment of vertebral osteomyelitis.

  15. Vertebral destruction due to abdominal aortic aneurysm

    PubMed Central

    Jiménez Viseu Pinheiro, J.F.; Blanco Blanco, J.F.; Pescador Hernández, D.; García García, F.J.

    2014-01-01

    Introduction Low back pain is a common cause of medical consultation, and usually supposes a non-malignant prognostic. Presentation of case We report an atypical appearance of low back pain associated to shock and pulsatile abdominal mass that made us diagnose an abdominal aortic aneurysm as reason of vertebral lysis and pain. Discusion Surgical repair of contained AAA should be directed to secondary re-rupture prevention, with an approximate survival near to 100% at selected patients for elective surgery. Consequently, orthopedic surgery for back spine stabilization has to be elective in those cases when vertebral destruction is above 30% and clinic is directly related to spine instability. Conclusion We should consider AAA as other cause of low back pain and routinely examine the abdomen and seek complementary imaging proves when risk factors for AAA are present. PMID:25569196

  16. Acute compressive myelopathy due to vertebral haemangioma

    PubMed Central

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

    2014-01-01

    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. PMID:24777075

  17. 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

  18. Light sensitivity in a vertebrate mechanoreceptor?

    PubMed Central

    Baker, Gary E.; de Grip, Willem J.; Turton, Michael; Wagner, Hans-Joachim; Foster, Russell G.; Douglas, Ron H.

    2015-01-01

    ABSTRACT Using immunohistochemistry and western blot analysis, we demonstrate that melanopsin is localised in cells around the central pore of lateral line neuromasts in the African clawed frog, Xenopus laevis. Since melanopsin is a known photoreceptor pigment with diverse functions in vertebrates, we suggest that the lateral line of Xenopus laevis, which is primarily a mechanoreceptor, might also be light sensitive. Potential functions of such photosensitivity are discussed, including its role in mediating locomotor responses following dermal illumination. PMID:26206352

  19. Transmission of Ranavirus between Ectothermic Vertebrate Hosts

    PubMed Central

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

    2014-01-01

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

  20. 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. PMID:25486407

  1. 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

  2. T-cell receptors in ectothermic vertebrates.

    PubMed

    Charlemagne, J; Fellah, J S; De Guerra, A; Kerfourn, F; Partula, S

    1998-12-01

    The structure and expression of genes encoding molecules homologous to mammalian T-cell receptors (TCR) have been recently studied in ectothermic vertebrate species representative of chondrychthians, teleosts, and amphibians. The overall TCR chain structure is well conserved in phylogeny: TCR beta- and TCR alpha-like chains were detected in all the species analyzed; TCR gamma- and TCR delta-like chains were also present in a chondrychthian species. The diversity potential of the variable (V) and joining (J) segments is rather large and, as in mammals, conserved diversity (D) segments are associated to the TCR beta and TCR delta chains. An important level of junctional diversity occurred at the V-(D)-J junctions, with the potential addition of N- and P-nucleotides. Thus, the conservation of the structure and of the potential of diversity of TCR molecules have been under a permanent selective pressure during vertebrate evolution. The structure of MHC class I and class II molecules was also well conserved in jawed vertebrates. TCR and MHC molecules are strongly functionally linked and play a determinant role in the initiation and the regulation of the specific immune responses; thus, it is not surprising that their structures have been reciprocally frozen during evolution. PMID:9914905

  3. 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. PMID:27030773

  4. The immunoglobulins of cold-blooded vertebrates.

    PubMed

    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

  5. Effects of hypoxia on vertebrate blood vessels.

    PubMed

    Russell, Michael J; Dombkowski, Ryan A; Olson, Kenneth R

    2008-03-01

    Hypoxia contracts mammalian respiratory vessels and increases vascular resistance in respiratory tissues of many vertebrates. In systemic vessels these responses vary, hypoxia relaxes mammalian vessels and contracts systemic arteries from cyclostomes. It has been proposed that hypoxic vasoconstriction in cyclostome systemic arteries is the antecedent to mammalian hypoxic pulmonary vasoconstriction, however, phylogenetic characterization of hypoxic responses is lacking. In this study, we characterized the hypoxic response of isolated systemic and respiratory vessels from a variety of vertebrates using standard myography. Pre-gill/respiratory (ventral aorta, afferent branchial artery, pulmonary artery) and post-gill/systemic (dorsal and thoracic aortas, efferent branchial artery) from lamprey (Petromyzon marinus), sandbar shark (Carcharhinus plumbeus), yellowfin tuna (Thunnus albacares), American bullfrog (Rana catesbeiana), American alligator (Alligator mississippiensis), Pekin duck (Anas platyrhynchos domesticus), chicken (Gallus domesticus) and rat (Rattus norvegicus) were exposed to hypoxia at rest or during pre-stimulation (elevated extracellular potassium, epinephrine or norepinephrine). Hypoxia produced a relaxation or transient contraction followed by relaxation in all pre-gill vessels, except for contraction in lamprey, and vasoconstriction or tri-phasic constriction-dilation-constriction in all pulmonary vessels. Hypoxia contracted systemic vessels from all animals except shark and rat and in pre-contracted rat aortas it produced a transient contraction followed by relaxation. These results show that while the classic "systemic hypoxic vasodilation and pulmonary hypoxic vasoconstriction" may occur in the microcirculation, the hypoxic response of the vertebrate macrocirculation is quite variable. These findings also suggest that hypoxic vasoconstriction is a phylogenetically ancient response. PMID:18214862

  6. 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

  7. 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

  8. FRAX and the effect of teriparatide on vertebral and non-vertebral fracture

    PubMed Central

    Harvey, Nicholas C; Kanis, John A; Odén, Anders; Burge, Russel T; Mitlak, Bruce H; Johansson, Helena; McCloskey, Eugene V

    2016-01-01

    Summary Daily teriparatide injections have been shown to reduce vertebral and non-vertebral fractures. Here we demonstrate that the magnitude of fracture risk reduction is independent of baseline fracture probability assessed by FRAX. Background Daily administration of 20μg or 40μg teriparatide has been shown to significantly decrease the risk of vertebral and non-vertebral fracture compared with placebo. The aim of the present study was to evaluate fracture risk assessed at baseline using the FRAX® tool and to determine the efficacy of teriparatide as a function of baseline fracture risk. Methods 1637 postmenopausal women in the pivotal phase 3 trial, randomly assigned to receive placebo (n=544), teriparatide 20 μg per day (n=541) or teriparatide 40 μg per day (n=552), were studied. Baseline clinical risk factors were entered into country-specific FRAX models to compute the 10-year probability of major osteoporotic fractures with or without input of femoral neck BMD. Because there was no difference in effect of 20 and 40μg teriparatide daily on fracture occurrence, the two active groups were merged. The interaction between probability of a major fracture and treatment efficacy was examined by Poisson regression. Results The 10-year probability of major osteoporotic fractures (with BMD) ranged from 2.2-67.2%. Treatment with teriparatide was associated with a 37% decrease in all non-vertebral fractures (95% CI:10-56 %) and a 56% decrease in low energy non-vertebral fractures (95% CI:24-75%) compared with placebo. The risk of morphometric vertebral fractures decreased significantly by 66% (95% CI:50-77%). Hazard ratios for the effect of teriparatide on the fracture outcome did not change significantly with increasing fracture probability (p>0.30). Similar findings were noted for the interaction when BMD was excluded from the FRAX model, or when probability of hip fracture was used as the marker of baseline risk. Conclusion We conclude that teriparatide

  9. Prospective Single-Site Experience with Radiofrequency-Targeted Vertebral Augmentation for Osteoporotic Vertebral Compression Fracture

    PubMed Central

    Moser, Franklin G.; Maya, Marcel M.; Blaszkiewicz, Laura; Scicli, Andrea; Miller, Larry E.; Block, Jon E.

    2013-01-01

    Vertebral augmentation procedures are widely used to treat osteoporotic vertebral compression fractures (VCFs). We report our initial experience with radiofrequency-targeted vertebral augmentation (RF-TVA) in 20 patients aged 50 to 90 years with single-level, symptomatic osteoporotic VCF between T10 and L5, back pain severity > 4 on a 0 to 10 scale, Oswestry Disability Index ≥ 21%, 20% to 90% vertebral height loss compared to adjacent vertebral body, and fracture age < 6 months. After treatment, patients were followed through hospital discharge and returned for visits after 1 week, 1 month, and 3 months. Back pain severity improved 66% (P < 0.001), from 7.9 (95% CI: 7.1 to 8.6) at pretreatment to 2.7 (95% CI: 1.5 to 4.0) at 3 months. Back function improved 46% (P < 0.001), from 74 (95% CI: 69% to 79%) at pretreatment to 40 (95% CI: 33% to 47%) at 3 months. The percentage of patients regularly consuming pain medication was 70% at pretreatment and only 21% at 3 months. No adverse events related to the device or procedure were reported. RF-TVA reduces back pain severity, improves back function, and reduces pain medication requirements with no observed complications in patients with osteoporotic VCF. PMID:24228187

  10. 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

  11. Embryo protection in contemporary immunology

    PubMed Central

    Fraune, Sebastian; Augustin, René

    2011-01-01

    Early embryos of many vertebrates and invertebrates develop outside the mother and are exposed to a myriad of potential microbial colonizers. Here we discuss how these embryos are protected from microbial attacks and how they might control and shape their microbiota. In essence we delineate a new role for antimicrobial peptides both in selecting particular bacterial partners during early development and in being important components of a “be prepared” strategy providing transgenerational protection. PMID:21966549

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

    PubMed

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

    1997-08-15

    To investigate the association between anthropometric indices and morphometrically determined vertebral deformity, the authors carried out a cross-sectional study using data from the European Vertebral Osteoporosis Study (EVOS), a population-based study of vertebral osteoporosis in 36 European centers from 19 countries. A total of 16,047 EVOS subjects were included in this analysis, of whom 1,973 subjects (915 males, 1,058 females) (12.3%) aged 50 years or over had one or more vertebral deformities ("cases"). The cases were compared with the 14,074 subjects (6,539 males, 7,535 females) with morphometrically normal spines ("controls"). Data were collected on self-reported height at age 25 years and minimum weight after age 25 years, as well as on current measured height and weight. Body mass index (BMI) and height and weight change were calculated from these data. The relations between these variables and vertebral deformity were examined separately by sex with logistic regression adjusting for age, smoking, and physical activity. In females, there was a significant trend of decreasing risk with increasing quintile of current weight, current BMI, and weight gain since age 25 years. In males, subjects in the lightest quintile for these measures were at increased risk but there was no evidence of a trend. An ecologic analysis by country revealed a negative correlation between mean BMI and the prevalence of deformity in females but not in males. The authors conclude that low body weight is associated with presence of vertebral deformity. PMID:9270407

  13. Early Bone Marrow Edema Pattern of the Osteoporotic Vertebral Compression Fracture : Can Be Predictor of Vertebral Deformity Types and Prognosis?

    PubMed Central

    Ahn, Sung Eun; Park, Ji Seon; Jin, Wook; Park, So Young; Kim, Sung Bum

    2016-01-01

    Objective To evaluate whether an early bone marrow edema pattern predicts vertebral deformity types and prognosis in osteoporotic vertebral compression fracture (OVCF). Methods This retrospective study enrolled 64 patients with 75 acute OVCFs who underwent early MRI and followed up MRI. On early MRI, the low SI pattern of OVCF on T1WI were assessed and classified into 3 types (diffuse, globular or patchy, band-like). On followed up MRI, the vertebral deformity types (anterior wedge, biconcave, crush), degree of vertebral body height loss, incidence of vertebral osteonecrosis and spinal stenosis were assessed for each vertebral fracture types. Results According to the early bone marrow edema pattern on T1WI, 26 vertebrae were type 1, 14 vertebrae were type 2 and 35 vertebrae were type 3. On followed up MRI, the crush-type vertebral deformity was most frequent among the type 1 OVCFs, the biconcave-type vertebral deformity was most frequent among the type 2 OVCFs and the anterior wedge-type vertebral deformity was most frequent among the type 3 OVCFs (p<0.001). In addition, type 1 early bone marrow edema pattern of OVCF on T1WI were associated with higher incidence of severe degree vertebral body height loss, vertebral osteonecrosis and spinal stenosis on the follow up MRI. Conclusion Early bone marrow edema pattern of OVCF on T1WI, significant correlated with vertebral deformity types on the follow up MRI. The severe degree of vertebral height loss, vertebral osteonecrosis, and spinal stenosis were more frequent in patients with diffuse low SI pattern. PMID:26962419

  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. Evolution of Vertebrate Phototransduction: Cascade Activation.

    PubMed

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

    2016-08-01

    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

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. The Vertebrate Primary Cilium in Development, Homeostasis, and Disease

    PubMed Central

    Gerdes, Jantje M.; Davis, Erica E.; Katsanis, Nicholas

    2010-01-01

    Cilia are complex structures that have garnered interest because of their roles in vertebrate development and their involvement in human genetic disorders. In contrast to multicellular invertebrates in which cilia are restricted to specific cell types, these organelles are found almost ubiquitously in vertebrate cells, where they serve a diverse set of signaling functions. Here, we highlight properties of vertebrate cilia, with particular emphasis on their relationship with other subcellular structures, and explore the physiological consequences of ciliary dysfunction. PMID:19345185

  3. Response of thoracolumbar vertebral bodies to high rate compressive loading - biomed 2013.

    PubMed

    Dooley, C J; Wester, B A; Wing, I D; Voo, L M; Armiger, R S; Merkle, A C

    2013-01-01

    Underbody blast (UBB) events created by improvised explosive devices are threats to warfighter survivability. High intensity blast waves emitted from these devices transfer large forces through vehicle structures to occupants, often resulting in injuries including debilitating spinal fractures. The vertical loading vector through the spine generates significant compressive forces at high strain rates. To better understand injury mechanisms and ultimately better protect vehicle occupants against UBB attacks, high-fidelity computational models are being developed to predict the human response to dynamic loading characteristic of these events. This effort details the results from a series of 23 high-rate compression tests on vertebral body specimen. A high-rate servo-hydraulic test system applied a range of compressive loading rates (.01 mm/s to 1238 mm/s) to vertebral bodies in the thoracolumbar region (T7-L5). The force-deflection curves generated indicate rate dependent sensitivity of vertebral stiffness, ultimate load and ultimate deflection. Specimen subjected to high-rate dynamic loading to failure experienced critical structural damage at 5.5% ± 2.1% deflection. Compared to quasi-static loading, vertebral bodies had greater stiffness, greater force to failure, and lower ultimate failure deflection at high rates. Post-failure, an average loss in height of 15% was observed, along with a mean reduction in strength of 48%. The resulting data from these tests will allow for enhanced biofidelity of computational models by characterizing the vertebral stiffness response and ultimate deflection at rates representative of UBB events. PMID:23686197

  4. Generation of Viable Plant-Vertebrate Chimeras.

    PubMed

    Alvarez, Marjorie; Reynaert, Nicole; Chávez, Myra N; 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

  5. 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. PMID:12957391

  6. Degenerative diseases of the vertebral column.

    PubMed

    Resnick, D

    1985-07-01

    Several distinct degenerative processes affect the articulations of the vertebral column; each is associated with characteristic radiographic and pathologic abnormalities, and many are accompanied by significant clinical manifestations. A discussion of these processes is best accomplished according to the type of joint that is involved. With regard to cartilaginous articulations, of which the intervertebral disk is most important, intervertebral (osteo)chondrosis, spondylosis deformans, and, in the cervical spine, uncovertebral arthrosis are the major degenerative disorders. Osteoarthritis (osteoarthrosis) affects any of the synovium-lined joints of the vertebral column, including the apophyseal, costovertebral, transitional lumbosacral, median atlantoaxial, and sacroiliac articulations. Fibrous articulations, ligaments, or entheses (sites of tendon or ligament attachment to bone) are involved in diffuse idiopathic skeletal hyperostosis, ossification of the posterior spinal ligaments, and Baastrup disease. Of the many complications of these degenerative processes, alignment abnormalities (including segmental instability, degenerative spondylolisthesis, senile kyphosis, and degenerative scoliosis), intervertebral disk displacement, calcification or ossification, and spinal stenosis are the most important. PMID:3923556

  7. What can vertebrates tell us about segmentation?

    PubMed Central

    2014-01-01

    Segmentation is a feature of the body plans of a number of diverse animal groupings, including the annelids, arthropods and chordates. However, it has been unclear whether or not these different manifestations of segmentation are independently derived or have a common origin. Central to this issue is whether or not there are common developmental mechanisms that establish segmentation and the evolutionary origins of these processes. A fruitful way to address this issue is to consider how segmentation in vertebrates is directed. During vertebrate development three different segmental systems are established: the somites, the rhombomeres and the pharyngeal arches. In each an iteration of parts along the long axis is established. However, it is clear that the formation of the somites, rhombomeres or pharyngeal arches have little in common, and as such there is no single segmentation process. These different segmental systems also have distinct evolutionary histories, thus highlighting the fact that segmentation can and does evolve independently at multiple points. We conclude that the term segmentation indicates nothing more than a morphological description and that it implies no mechanistic similarity. Thus it is probable that segmentation has arisen repeatedly during animal evolution. PMID:25009737

  8. 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

  9. 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.

  10. The origins and evolution of vertebrate metamorphosis.

    PubMed

    Laudet, Vincent

    2011-09-27

    Metamorphosis, classically defined as a spectacular post-embryonic transition, is well exemplified by the transformation of a tadpole into a frog. It implies the appearance of new body parts (such as the limbs), the resorption of larval features (such as the tail) and the remodelling of many organs (such as the skin or the intestine). In vertebrates, metamorphosis has been well characterized in anuran amphibians, where thyroid hormones orchestrate the intricate and seemingly contradictory changes observed at the cellular and tissue levels. Thyroid hormones control a complex hierarchical cascade of target genes via binding to specific receptors, TRα and TRβ, ligand-activated transcription factors belonging to the nuclear receptor superfamily. Metamorphosis is actually widespread in the vertebrates, though quite diverse in the way it manifests in a particular species. Furthermore, evolutionary and ecological variations of this key event, from paedomorphosis to direct development, provide an excellent illustration of how tinkering with a control pathway can lead to divergent life histories. The study of invertebrate chordates has also shed light on the origin of metamorphosis. The available data suggest that post-embryonic remodelling governed by thyroid hormones is an ancestral feature of chordates. According to this view, metamorphosis of the anurans is an extreme example of a widespread life history transition. PMID:21959163

  11. 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.

  12. Recursive splicing in long vertebrate genes

    PubMed Central

    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

    2015-01-01

    It is generally believed that splicing removes introns as single units from pre-mRNA transcripts. However, some long D. melanogaster introns contain a cryptic site, called a recursive splice site (RS-site), that enables a multi-step process of intron removal termed recursive splicing1,2. The extent to which recursive splicing occurs in other species and its mechanistic basis remain unclear. 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 a “RS-exon” that follows the RS-site. The RS-exon is then excluded from the dominant mRNA isoform due 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 exons or promoters that are prevalent in long introns, but which fail to reconstitute an efficient 5′ splice site. Most RS-exons contain a premature stop codon such that their inclusion may decrease mRNA stability. Thus, by establishing a binary splicing switch, RS-sites demarcate different mRNA isoforms emerging from long genes by coupling inclusion of cryptic elements with RS-exons. PMID:25970246

  13. 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

  14. 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. PMID:25970246

  15. 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

  16. 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

  17. Neural induction and early patterning in vertebrates.

    PubMed

    Ozair, Mohammad Zeeshan; Kintner, Chris; Brivanlou, Ali H

    2013-07-01

    In vertebrates, the development of the nervous system is triggered by signals from a powerful 'organizing' region of the early embryo during gastrulation. This phenomenon--neural induction--was originally discovered and given conceptual definition by experimental embryologists working with amphibian embryos. Work on the molecular circuitry underlying neural induction, also in the same model system, demonstrated that elimination of ongoing transforming growth factor-β (TGFβ) signaling in the ectoderm is the hallmark of anterior neural-fate acquisition. This observation is the basis of the 'default' model of neural induction. Endogenous neural inducers are secreted proteins that act to inhibit TGFβ ligands in the dorsal ectoderm. In the ventral ectoderm, where the signaling ligands escape the inhibitors, a non-neural fate is induced. Inhibition of the TGFβ pathway has now been demonstrated to be sufficient to directly induce neural fate in mammalian embryos as well as pluripotent mouse and human embryonic stem cells. Hence the molecular process that delineates neural from non-neural ectoderm is conserved across a broad range of organisms in the evolutionary tree. The availability of embryonic stem cells from mouse, primates, and humans will facilitate further understanding of the role of signaling pathways and their downstream mediators in neural induction in vertebrate embryos. PMID:24014419

  18. 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. PMID:25959851

  19. 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

  20. Dominance in vertebrate broods and litters.

    PubMed

    Drummond, Hugh

    2006-03-01

    Drawing on the concepts and theory of dominance in adult vertebrates, this article categorizes the relationships of dominance between infant siblings, identifies the behavioral mechanisms that give rise to those relationships, and proposes a model to explain their evolution. Dominance relationships in avian broods can be classified according to the agonistic roles of dominants and subordinates as "aggression-submission," "aggression-resistance," "aggression-aggression," "aggression-avoidance," "rotating dominance," and "flock dominance." These relationships differ mainly in the submissiveness/pugnacity of subordinates, which is pivotal, and in the specificity/generality of the learning processes that underlie them. As in the dominance hierarchies of adult vertebrates, agonistic roles are engendered and maintained by several mechanisms, including differential fighting ability, assessment, trained winning and losing (especially in altricial species), learned individual relationships (especially in precocial species), site-specific learning, and probably group-level effects. An evolutionary framework in which the species-typical dominance relationship is determined by feeding mode, confinement, cost of subordination, and capacity for individual recognition, can be extended to mammalian litters and account for the aggression-submission and aggression-resistance observed in distinct populations of spotted hyenas and the "site-specific dominance" (teat ownership) of some pigs, felids, and hyraxes. Little is known about agonism in the litters of other mammals or broods of poikilotherms, but some species of fish and crocodilians have the potential for dominance among broodmates. PMID:16602272

  1. Health impact associated with vertebral deformities: results from the European Vertebral Osteoporosis Study (EVOS).

    PubMed

    Matthis, C; Weber, U; O'Neill, T W; Raspe, H

    1998-01-01

    To study the association between vertebral deformities and subjective health outcome indicators, including back pain and disability, a cross-sectional survey with spinal radiographs and personal interviews was carried out in 36 study centres in 19 European countries on a total of 15,570 men and women aged 50-79 years (population-based stratified random samples). No interventions were done. The main outcome measures were the presence and intensity of current and previous back pain, functional capacity (ADL questionnaire) and overall subjective health. The presence and intensity of back pain and functional and health impairments varied within wide ranges with no obvious regional pattern. However, the associations between negative health outcomes and vertebral deformity were homogeneous between countries and between centres within countries. In logistic regression analyses weak but significant associations between the presence of vertebral deformities and various health indicators were demonstrated. The magnitude of the associations increased with severity and number of deformities. Compared with subjects without deformities those with low-grade deformities had no or only a weakly elevated risk for back pain, disability and impaired subjective health (odds ratios (OR) 1.2-1.3). The odds ratios increased for individuals with single severe deformities (OR 1.3-2.1) and were highest in those with multiple severe deformities (OR 1.7-4.2). The associations between vertebral deformities and negative health outcomes were stronger in men than in women. In this cross-sectional study radiologically assessed vertebral deformities were therefore weakly associated with both current and previous back pain as well as with functional and health impairments in both women and men. Multiple severe deformities were associated with severe and disabling back pain with stronger effects in men. PMID:10024907

  2. 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

  3. 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. PMID:25943906

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

    PubMed

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

    2015-07-01

    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

  5. Candidal Vertebral Osteomyelitis in the Midst of Renal Disorders.

    PubMed

    Gopinathan, Anusha; Kumar, Anil; Rao, Srivatsa Nagaraja; Kumar, Krishna; Karim, Shamsul

    2016-04-01

    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

  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. 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

  8. Tick subolesin is an ortholog of the akirins described in insects and vertebrates.

    PubMed

    Galindo, Ruth C; Doncel-Pérez, Ernesto; Zivkovic, Zorica; Naranjo, Victoria; Gortazar, Christian; Mangold, Atilio J; Martín-Hernando, María Paz; Kocan, Katherine M; de la Fuente, José

    2009-04-01

    The tick protective antigen, subolesin, is a regulatory protein involved in the control of multiple cellular pathways. Subolesin is evolutionary conserved in invertebrates and vertebrates with sequence homology to akirins, a recently renamed group of proteins that were proposed to function as transcription factors in Drosophila and mice. The objective of this research was to provide evidence of the sequence and functional homology between tick subolesin and akirins. The phylogenetic analysis of subolesin and akirins showed that they are evolutionary conserved. The effect of subolesin and akirin2 knockdown was compared in adult ticks and mice, respectively. The results demonstrated that tick subolesin is an ortholog of insect and vertebrate akirins and suggested that these proteins function in the regulation of NF-kappaB-dependent and independent expression of signal transduction and innate immune response genes. These results suggest that these proteins have an important role in host-pathogen interactions. PMID:19041667

  9. Effects of desert wildfires on desert tortoise (Gopherus agassizii) and other small vertebrates

    USGS Publications Warehouse

    Esque, T.C.; Schwalbe, C.R.; DeFalco, L.A.; Duncan, R.B.; Hughes, T.J.

    2003-01-01

    We report the results of standardized surveys to determine the effects of wildfires on desert tortoises (Gopherus agassizii) and their habitats in the northeastern Mojave Desert and northeastern Sonoran Desert. Portions of 6 burned areas (118 to 1,750 ha) were examined for signs of mortality of vertebrates. Direct effects of fire in desert habitats included animal mortality and loss of vegetation cover. A range of 0 to 7 tortoises was encountered during surveys, and live tortoises were found on all transects. In addition to desert tortoises, only small (<1 kg) mammals and reptiles (11 taxa) were found dead on the study areas. We hypothesize that indirect effects of fire on desert habitats might result in changes in the composition of diets and loss of vegetation cover, resulting in an increase in predation and loss of protection from temperature extremes. These changes in habitat also might cause changes in vertebrate communities in burned areas.

  10. 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

  11. 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

  12. Routine needle biopsy during vertebral augmentation procedures. Is it necessary?

    PubMed

    Pneumaticos, Spiros G; Chatziioannou, Sofia N; Savvidou, Christiana; Pilichou, Anastasia; Rontogianni, Dimitra; Korres, Dimitrios S

    2010-11-01

    Vertebral augmentation procedures are currently widely performed to treat vertebral compression fractures. The purpose of this study was to determine the frequency of underlying previously unrecognized etiology in a consecutive series of patients undergoing kyphoplasty to treat vertebral compression fractures. A prospective histological evaluation of vertebral body biopsy specimens from presumed osteoporotic vertebral compression fractures were performed in order to identify aforementioned causes. Over a 2-year period, vertebral body biopsies from 154 vertebral levels were performed in 75 patients undergoing kyphoplasty for vertebral compression fractures. All patients received a preoperative workup that included plain radiographs, MRI, whole body bone scan, and laboratory examinations. Bone specimens were obtained from affected vertebral bodies and submitted for histologic evaluation to identify the prevalence of an underlying cause. All specimens demonstrated fragmented bone with variable amounts of unmineralised bone, signs of bone-remodeling and/or fracture-healing. In 11 patients underlying pathology other than osteoporosis was identified (prostate cancer, 1; pancreatic cancer, 1; colon cancer, 1; breast cancer, 2; multiple myeloma, 3; leukemia, 1; and lung cancer, 2). In all but one patient the results of the biopsy confirmed the diagnosis suspected from the preoperative workup. For the last patient, namely the one with pancreatic cancer, the workup did not identify the origin of the primary tumor, although the patient was considered to have a compression fracture secondary to metastatic disease of unknown origin, the vertebral biopsy suggested the presence of adenocarcinoma which eventually was proven to be pancreatic cancer. In augmentation procedures for vertebral compression fractures, bone biopsy should be reserved for the patients where the preoperative evaluation raises the suspicion of a non-osteoporotic etiology. PMID:20372942

  13. Ischemic stroke: carotid and vertebral artery disease.

    PubMed

    Vilela, P; Goulão, A

    2005-03-01

    Ischemic strokes may have distinct aetiologies, including several different intrinsic arterial pathological disorders. The diagnosis and understanding of these arterial diseases is critical for the correct management of stroke as different treatment approaches are undertaken according to the aetiology. Atherosclerosis is by far the most common arterial disease among adults, and other pathological processes include arterial dissection, small vessel disease, inflammatory and non-inflammatory vasculopathy and vasomotor disorders. In children, there are several vasculopathies responsible for vaso-occlusive disease such as sickle-cell anemia, acute regressive angiopathy and Moya-Moya disease, neurofibromatosis, dissections, vasculitis associated with intracranial and systemic infections. An overview of the major carotid and vertebral pathological diseases responsible for ischemic stroke in adults and children, highlighting the accuracy of the different imaging modalities for its diagnosis and the imaging appearance of these diseases, is given. PMID:15657789

  14. Morphogenesis and evolution of vertebrate appendicular muscle.

    PubMed

    Haines, L; Currie, P 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

  15. De Novo Genesis of Enhancers in Vertebrates

    PubMed Central

    Eichenlaub, Michael P.; Ettwiller, Laurence

    2011-01-01

    Evolutionary innovation relies partially on changes in gene regulation. While a growing body of evidence demonstrates that such innovation is generated by functional changes or translocation of regulatory elements via mobile genetic elements, the de novo generation of enhancers from non-regulatory/non-mobile sequences has, to our knowledge, not previously been demonstrated. Here we show evidence for the de novo genesis of enhancers in vertebrates. For this, we took advantage of the massive gene loss following the last whole genome duplication in teleosts to systematically identify regions that have lost their coding capacity but retain sequence conservation with mammals. We found that these regions show enhancer activity while the orthologous coding regions have no regulatory activity. These results demonstrate that these enhancers have been de novo generated in fish. By revealing that minor changes in non-regulatory sequences are sufficient to generate new enhancers, our study highlights an important playground for creating new regulatory variability and evolutionary innovation. PMID:22069375

  16. Control of segment number in vertebrate embryos.

    PubMed

    Gomez, Céline; Ozbudak, Ertuğrul M; Wunderlich, Joshua; Baumann, Diana; Lewis, Julian; Pourquié, Olivier

    2008-07-17

    The vertebrate body axis is subdivided into repeated segments, best exemplified by the vertebrae that derive from embryonic somites. The number of somites is precisely defined for any given species but varies widely from one species to another. To determine the mechanism controlling somite number, we have compared somitogenesis in zebrafish, chicken, mouse and corn snake embryos. Here we present evidence that in all of these species a similar 'clock-and-wavefront' mechanism operates to control somitogenesis; in all of them, somitogenesis is brought to an end through a process in which the presomitic mesoderm, having first increased in size, gradually shrinks until it is exhausted, terminating somite formation. In snake embryos, however, the segmentation clock rate is much faster relative to developmental rate than in other amniotes, leading to a greatly increased number of smaller-sized somites. PMID:18563087

  17. 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

  18. Spontaneous resolution of lumbar vertebral eosinophilic granuloma.

    PubMed

    Bavbek, M; Atalay, B; Altinörs, N; Caner, H

    2004-02-01

    Eosinophilic granuloma (EG) is a rare disease but is more common in adults than children. It's often self-limiting. Spinal involvement is rare. It is the localized and most benign form of Langerhans' cell histiocytosis (previously known as histiocytosis X), characterised by lytic lesions in one or more bones. Spontaneous resolution of vertebral body lesions is very rare. In this case, the patient had one EG in a cervical vertebra and a similar lesion in a lumbar vertebra. This case is important because it featured a symptomatic lesion in the cervical spine accompanied by an asymptomatic lesion in a lumbar vertebra. We treated the cervical lesion by surgical fusion and followed the lumbar lesion up conservatively, with the patient in a corset. After 8 years of follow-up, control MRI showed that the lumbar lesion had spontaneously resolved. PMID:14963750

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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. PMID:12629209

  5. A systematic approach to vertebral hemangioma.

    PubMed

    Gaudino, Simona; Martucci, Matia; Colantonio, Raffaella; Lozupone, Emilio; Visconti, Emiliano; Leone, Antonio; Colosimo, Cesare

    2015-01-01

    Vertebral hemangiomas (VHs) are a frequent and often incidental finding on computed tomography (CT) and magnetic resonance (MR) imaging of the spine. When their imaging appearance is "typical" (coarsened vertical trabeculae on radiographic and CT images, hyperintensity on T1- and T2-weighted MR images), the radiological diagnosis is straightforward. Nonetheless, VHs might also display an "atypical" appearance on MR imaging because of their histological features (amount of fat, vessels, and interstitial edema). Although the majority of VHs are asymptomatic and quiescent lesions, they can exhibit active behaviors, including growing quickly, extending beyond the vertebral body, and invading the paravertebral and/or epidural space with possible compression of the spinal cord and/or nerve roots ("aggressive" VHs). These "atypical" and "aggressive" VHs are a radiological challenge since they can mimic primary bony malignancies or metastases. CT plays a central role in the workup of atypical VHs, being the most appropriate imaging modality to highlight the polka-dot appearance that is representative of them. When aggressive VHs are suspected, both CT and MR are needed. MR is the best imaging modality to characterize the epidural and/or soft-tissue component, helping in the differential diagnosis. Angiography is a useful imaging adjunct for evaluating and even treating aggressive VHs. The primary objectives of this review article are to summarize the clinical, pathological, and imaging features of VHs, as well as the treatment options, and to provide a practical guide for the differential diagnosis, focusing on the rationale assessment of the findings from radiography, CT, and MR imaging. PMID:25348558

  6. 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. PMID:27261254

  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. 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…

  9. Percutaneous pediculoplasty: polymethylmethacrylate injection into lytic vertebral pedicle lesions.

    PubMed

    Gailloud, Philippe; Beauchamp, Norman J; Martin, Jean-Baptiste; Murphy, Kieran J

    2002-05-01

    Two patients with painful lytic lesions of the vertebral pedicle were treated with percutaneous pediculoplasty. This technique, similar to vertebroplasty but with increased procedural risks because of the immediate vicinity of neural structures, was performed under high-quality biplane fluoroscopic guidance. For lesions involving both the pedicle and the vertebral body, a double-needle unipedicular technique is advocated. PMID:11997361

  10. Thoracic vertebral osteomyelitis: an unusual complication of Crohn's disease.

    PubMed

    Ajayi, Olushola; Mayooran, Nithiananthan; Iqbal, Nasir

    2014-01-01

    Vertebral osteomyelitis complicating Crohn's disease is a rare occurrence and mostly occurred in patients with Crohn's disease complicated by an abscess or fistulising disease. We report a case of thoracic vertebral osteomyelitis, occurring in a refractory Crohn's disease without contiguous abscess or fistula with the bowel. PMID:24916975

  11. Evolution, structure, and synthesis of vertebrate egg-coat proteins

    PubMed Central

    Litscher, Eveline S.; Wassarman, Paul M.

    2015-01-01

    All vertebrate eggs are surrounded by an extracellular coat that supports growth of oocytes, protects oocytes, eggs, and early embryos, and participates in the process of fertilization. In mammals (platypus to human beings) the coat is called a zona pellucida (ZP) and in non-mammals (molluscs to birds), a vitelline envelope (VE). The ZP and VE are composed of just a few proteins that are related to one another and possess a common motif, called the zona pellucida domain (ZPD). The ZPD arose more than ~600 million years ago, consists of ~260 amino acids, and has 8 conserved Cys residues that participate in 4 intramolecular disulfides. It is likely that egg-coat proteins are derived from a common ancestral gene. This gene duplicated several times during evolution and gave rise to 3–4 genes in fish, 5 genes in amphibians, 6 genes in birds, and 3–4 genes in mammals. Some highly divergent sequences, N- and C-terminal to the ZPD, have been identified in egg-coat proteins and some of these sequences may be under positive Darwinian selection that drives evolution of the proteins. These and other aspects of egg-coat proteins, including their structure and synthesis, are addressed in this review. PMID:26504367

  12. A Novel Canine Model of Acute Vertebral Artery Occlusion

    PubMed Central

    Zhang, Yunfeng; Jin, Min; Du, Bin; Lin, Hao; Xu, Chengyong; Jiang, Weijian; Jia, Jianping

    2015-01-01

    Background The extended time window and theoretic reduction in hemorrhage make mechanical strategies an attractive approach for the treatment of patients with ischemic stroke. However, a limited availability of suitable animal models of cerebrovascular thrombosis has hampered the study of novel endovascular interventions. The aim of the present study was to develop a new technique for site-specific placement of a thrombus in a canine model that would allow for the evaluation of mechanical thrombectomy and clot retrieval methods and the visualization of thrombus dislocation or fragmentation during angiographic manipulation. Methods Angiography and embolization with a preformed thrombus were performed in 12 canines. Under fluoroscopic guidance, an embolism protection device (EPD) was anchored to the middle segment of the left vertebral artery (VA) via the left femoral arterial sheath. A preformed radiopaque clot was injected through the guide catheter into the left VA, via the contralateral femoral artery, proximal to the EPD. After 15 min of occlusion, the EPD was removed and persistent occlusion of the VA was documented angiographically. Results Angiography performed during the observation period confirmed the persistence of VA occlusion in each case, and displacement of the radiopaque clots did not occur during the 3-hour observation period. The technique allowed selective embolization of targeted vessels without thrombus fragmentation. Conclusion This study demonstrates, for the first time, a canine model of post-circulation embolism induced by autologous blood clot placement. This model can be rapidly formed and easily operated, and the site of thrombosis can be readily controlled. PMID:26545253

  13. Avoidance and tolerance of freezing in ectothermic vertebrates.

    PubMed

    Costanzo, Jon P; Lee, Richard E

    2013-06-01

    Ectothermic vertebrates have colonized regions that are seasonally or perpetually cold, and some species, particularly terrestrial hibernators, must cope with temperatures that fall substantially below 0°C. Survival of such excursions depends on either freeze avoidance through supercooling or freeze tolerance. Supercooling, a metastable state in which body fluids remain liquid below the equilibrium freezing/melting point, is promoted by physiological responses that protect against chilling injury and by anatomical and behavioral traits that limit risk of inoculative freezing by environmental ice and ice-nucleating agents. Freeze tolerance evolved from responses to fundamental stresses to permit survival of the freezing of a substantial amount of body water under thermal and temporal conditions of ecological relevance. Survival of freezing is promoted by a complex suite of molecular, biochemical and physiological responses that limit cell death from excessive shrinkage, damage to macromolecules and membranes, metabolic perturbation and oxidative stress. Although freeze avoidance and freeze tolerance generally are mutually exclusive strategies, a few species can switch between them, the mode used in a particular instance of chilling depending on prevailing physiological and environmental conditions. PMID:23678097

  14. De novo synthesis of a sunscreen compound in vertebrates

    PubMed Central

    Osborn, Andrew R; Almabruk, Khaled H; Holzwarth, Garrett; Asamizu, Shumpei; LaDu, Jane; Kean, Kelsey M; Karplus, P Andrew; Tanguay, Robert L; Bakalinsky, Alan T; Mahmud, Taifo

    2015-01-01

    Ultraviolet-protective compounds, such as mycosporine-like amino acids (MAAs) and related gadusols produced by some bacteria, fungi, algae, and marine invertebrates, are critical for the survival of reef-building corals and other marine organisms exposed to high-solar irradiance. These compounds have also been found in marine fish, where their accumulation is thought to be of dietary or symbiont origin. In this study, we report the unexpected discovery that fish can synthesize gadusol de novo and that the analogous pathways are also present in amphibians, reptiles, and birds. Furthermore, we demonstrate that engineered yeast containing the fish genes can produce and secrete gadusol. The discovery of the gadusol pathway in vertebrates provides a platform for understanding its role in these animals, and the possibility of engineering yeast to efficiently produce a natural sunscreen and antioxidant presents an avenue for its large-scale production for possible use in pharmaceuticals and cosmetics. DOI: http://dx.doi.org/10.7554/eLife.05919.001 PMID:25965179

  15. Applications of memory alloy stent in vertebral fractures

    PubMed Central

    Yimin, Yang; Zhi, Zhang; ZhiWei, Ren; Wei, Ma; Jha, Rajiv Kumar

    2014-01-01

    Background The aim of this study was to evaluate the feasibility of treating vertebral compression fractures using an autonomously developed nitinol memory alloy vertebral stent. Material/Methods Thoracolumbar vertebral specimens from adult human cadavers were made into models of compression fractures. The models were divided into group A, which received percutaneous kyphoplasty (PKP), balloon dilation, and nitinol memory alloy vertebral stent implantation (PKP + nitinol stent group); group B, which received percutaneous vertebroplasty (PVP) and direct implantation of a nitinol memory alloy vertebral stent (PVP + nitinol stent group); and group C, which received PKP, balloon dilation, and bone cement vertebroplasty (PKP + polymethylmethacrylate (PMMA) group). Vertebral heights were measured before and after the surgery and the water bath incubation to compare the impact of the 3 different surgical approaches on reducing vertebral compression. Results The 3 surgical groups could all significantly restore the heights of compressed vertebral bodies. The vertebral heights of the PKP + nitinol stent group, PVP + nitinol stent group, and PKP + PMMA group were changed from the preoperative levels of (1.59±0.08) cm, (1.68±0.08) cm, and (1.66±0.11) cm to the postoperative levels of (2.00±0.09) cm, (1.87±0.04) cm, and (1.99±0.09) cm, respectively. After the water bath, the vertebral heights of each group were changed to (2.10±0.07) cm, (1.98±0.09) cm, and (2.00±0.10) cm, respectively. Pairwise comparison of the differences between the preoperative and postoperative vertebral heights showed that group A and group B differed significantly (P=0.000); group B and group C differed significantly (P=0.003); and group A and group C had no significant difference (P=0.172). Pairwise comparison of the differences in the vertebral heights before and after the water bath showed that group A and group C differed significantly (P=0.000); group B and group C differed significantly

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

    SciTech Connect

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

    2009-09-15

    The purpose of this study was to investigate geometrical stability and preservation of height gain of vertebral bodies after percutaneous vertebroplasty during 2 years' follow-up and to elucidate the geometric remodeling process of the vertebral bidisk unit (VDU) of the affected segment. Patients with osteoporotic vertebral compression fractures with pain resistant to analgetic drugs were treated with polymethylmethacrylate vertebroplasty. Mean {+-} standard error cement volume was 5.1 {+-} 2.0 ml. Vertebral geometry was documented by sagittal and coronal reformations from multidetector computed tomography data sets: anterior, posterior, and lateral vertebral heights, end plate angles, and compression index (CI = anterior/posterior height). Additionally, the VDU (vertebral bodies plus both adjacent disk spaces) was calculated from the multidetector computed tomography data sets: anterior, posterior, and both lateral aspects. Patients were assigned to two groups: moderate compression with CI of >0.75 (group 1) and severe compression with CI of <0.75 (group 2). A total of 83 vertebral bodies of 30 patients (7 men, 23 women, age 70.7 {+-} 9.7 years, range 40-82 years) were treated with vertebroplasty and prospectively followed for 24 months. In the moderate compression group (group 1), the vertebral heights were stabilized over time at the preinterventional levels. Compared with group 1, group 2 showed a greater anterior height gain (+2.8 {+-} 2.2 mm vs. +0.8 {+-} 2.0 mm, P < 0.001), better reduction of end plate angle (-4.9 {+-} 4.8{sup o} vs. -1.0 {+-} 2.7{sup o}, P < 0.01), and improved CI (+0.12 {+-} 0.13 vs. +0.02 {+-} 0.07, P < 0.01) and demonstrated preserved anterior height gain at 2 years (+1.2 {+-} 3.2 mm, P < 0.01) as well as improved end plate angles (-5.2 {+-} 5.0{sup o}, P < 0.01) and compression indices (+0.11 {+-} 0.15, P < 0.01). Thus, posterior height loss of vertebrae and adjacent intervertebral disk spaces contributed to a remodeling of the VDU

  17. Evolution of the Vertebrate Cranium: Viewed from Hagfish Developmental Studies.

    PubMed

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

    2016-06-01

    Our knowledge of vertebrate cranium evolution has relied largely on the study of gnathostomes. Recent evolutionary and developmental studies of cyclostomes have shed new light on the history of the vertebrate skull. The recent ability to obtain embryos of the hagfish, Eptatretus burgeri, has enabled new studies which have suggested an embryonic morphological pattern (the "cyclostome pattern") of craniofacial development. This pattern is shared by cyclostomes, but not by modern jawed vertebrates. Because this pattern of embryonic head development is thought to be present in some stem gnathostomes (ostracoderms), it is possible that the cyclostome pattern represents the vertebrate ancestral pattern. The study of cyclostomes may thus lead to an understanding of the most ancestral basis of craniofacial development. In this review, we summarize the development of the hagfish chondrocranium in light of the cyclostome pattern, present an updated comparison of the cyclostome chondrocranium, and discuss several aspects of the evolution and development of the vertebrate skull. PMID:27268976

  18. Nuisance arthropods, nonhost odors, and vertebrate chemical aposematism

    NASA Astrophysics Data System (ADS)

    Weldon, Paul J.

    2010-05-01

    Mosquitoes, ticks, and other ectoparasitic arthropods use chemoreception to avoid vertebrates that are known or presumed to be dangerous or otherwise unprofitable hosts. Nonhosts may belong to a species that is regularly unaccepted or one that includes both accepted and unaccepted individuals. A diverse array of qualities including immunocompetence, vigilant grooming behavior, mechanical inaccessibility, and toxicity have been proposed as the features that render vertebrate chemical emitters unsuitable as hosts for arthropods. In addition to advantages accrued by ectoparasitic arthropods that avoid nonhosts, vertebrates that are not accepted as hosts benefit by evading injurious ectoparasites and the infectious agents they transmit. The conferral of advantages to both chemical receivers (ectoparasitic arthropods) and emitters (unpreferred vertebrates) in these interactions renders nonhost odors aposematic. Chemical aposematism involving ectoparasites selects for vertebrates that emit distinctive odors. In addition, chemical mimicry, where vulnerable organisms benefit when misidentified as nonhosts, may be accommodated by duped ectoparasites.

  19. The generation of vertebral segmental patterning in the chick embryo

    PubMed Central

    Senthinathan, Biruntha; Sousa, Cátia; Tannahill, David; Keynes, Roger

    2012-01-01

    We have carried out a series of experimental manipulations in the chick embryo to assess whether the notochord, neural tube and spinal nerves influence segmental patterning of the vertebral column. Using Pax1 expression in the somite-derived sclerotomes as a marker for segmentation of the developing intervertebral disc, our results exclude such an influence. In contrast to certain teleost species, where the notochord has been shown to generate segmentation of the vertebral bodies (chordacentra), these experiments indicate that segmental patterning of the avian vertebral column arises autonomously in the somite mesoderm. We suggest that in amniotes, the subdivision of each sclerotome into non-miscible anterior and posterior halves plays a critical role in establishing vertebral segmentation, and in maintaining left/right alignment of the developing vertebral elements at the body midline. PMID:22458512

  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. PMID:24533544

  1. The Lamprey: A jawless vertebrate model system for examining origin of the neural crest and other vertebrate traits

    PubMed Central

    Green, Stephen A.; Bronner, Marianne E.

    2014-01-01

    Summary Lampreys are a group of jawless fishes that serve as an important point of comparison for studies of vertebrate evolution. Lampreys and hagfishes are agnathan fishes, the cyclostomes, which sit at a crucial phylogenetic position as the only living sister group of the jawed vertebrates. Comparisons between cyclostomes and jawed vertebrates can help identify shared derived (i.e. synapomorphic) traits that might have been inherited from ancestral early vertebrates, if unlikely to have arisen convergently by chance. One example of a uniquely vertebrate trait is the neural crest, an embryonic tissue that produces many cell types crucial to vertebrate features, such as the craniofacial skeleton, pigmentation of the skin, and much of the peripheral nervous system (Gans and Northcutt, 1983). Invertebrate chordates arguably lack unambiguous neural crest homologs, yet have cells with some similarities, making comparisons with lampreys and jawed vertebrates essential for inferring characteristics of development in early vertebrates, and how they may have evolved from nonvertebrate chordates. Here we review recent research on cyclostome neural crest development, including research on lamprey gene regulatory networks and differentiated neural crest fates. PMID:24560767

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

    PubMed Central

    FOLEY, ANN C.; STERN, CLAUDIO D.

    2001-01-01

    addition, the hypoblast plays a role in directing cell movements in the adjacent epiblast. These movements distance the future forebrain territory from the developing organiser (Hensen's node), and we suggest that this is a mechanism to protect the forebrain from caudalising signals from the node. These mechanisms are consistent with all the findings obtained from the mouse to date. We conclude that the mechanisms responsible for setting up the forebrain and more caudal regions of the nervous system are probably similar among different classes of higher vertebrates. Moreover, while reconciling the two main models, our findings provide stronger support for Nieuwkoop's ideas than for the concept of multiple organisers, each inducing a distinct region of the CNS. PMID:11523828

  3. Coastal Vertebrate Exposure to Predicted Habitat Changes Due to Sea Level Rise

    NASA Astrophysics Data System (ADS)

    Hunter, Elizabeth A.; Nibbelink, Nathan P.; Alexander, Clark R.; Barrett, Kyle; Mengak, Lara F.; Guy, Rachel K.; Moore, Clinton T.; Cooper, Robert J.

    2015-12-01

    Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species' fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species ( n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species' foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.

  4. Evolutionary conservation of vertebrate blood-brain barrier chemoprotective mechanisms in Drosophila

    PubMed Central

    Mayer, Fahima; Mayer, Nasima; Chinn, Leslie; Pinsonneault, Robert L.; Kroetz, Deanna; Bainton, Roland J.

    2011-01-01

    Pharmacologic remedy of many brain diseases is difficult because of the powerful drug exclusion properties of the blood-brain barrier (BBB). Chemical isolation of the vertebrate brain is achieved through the highly integrated, anatomically compact and functionally overlapping chemical isolation processes of the BBB. These include functions that need to be coordinated between tight diffusion junctions and unidirectionally-acting xenobiotic transporters. Understanding of many of these processes has been hampered, as they are not well mimicked by ex vivo models of the BBB and have been experimentally difficult and expensive to disentangle in intact rodent models. Here we show that the Drosophila melanogaster (Dm) humoral/CNS barrier conserves the xenobiotic exclusion properties found in the vertebrate vascular endothelium. We characterize a fly ABC transporter, Mdr65, that functions similar to mammalian xenobiotic BBB transporters and show that varying its levels solely in the Dm BBB changes the inherent sensitivity of the barrier to cytotoxic pharmaceuticals. Furthermore we demonstrate orthologous function between Mdr65 and vertebrate ABC transporters by rescuing chemical protection of the Dm brain with human MDR1/Pgp. These data indicate that the ancient origins of CNS chemoprotection extend to both conserved molecular means and functionally analogous anatomic spaces that together promote CNS selective drug partition. Thus, Dm presents an experimentally tractable system for analyzing physiological properties of the BBB in an intact organism. PMID:19295159

  5. Coastal Vertebrate Exposure to Predicted Habitat Changes Due to Sea Level Rise.

    PubMed

    Hunter, Elizabeth A; Nibbelink, Nathan P; Alexander, Clark R; Barrett, Kyle; Mengak, Lara F; Guy, Rachel K; Moore, Clinton T; Cooper, Robert J

    2015-12-01

    Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species' fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species (n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species' foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR. PMID:26163199

  6. Coastal vertebrate exposure to predicted habitat changes due to sea level rise

    USGS Publications Warehouse

    Hunter, Elizabeth A.; Nibbelink, Nathan P.; Alexander, Clark R.; Barrett, Kyle; Mengak, Lara F.; Guy, Rachel; Moore, Clinton; Cooper, Robert J.

    2015-01-01

    Sea level rise (SLR) may degrade habitat for coastal vertebrates in the Southeastern United States, but it is unclear which groups or species will be most exposed to habitat changes. We assessed 28 coastal Georgia vertebrate species for their exposure to potential habitat changes due to SLR using output from the Sea Level Affecting Marshes Model and information on the species’ fundamental niches. We assessed forecasted habitat change up to the year 2100 using three structural habitat metrics: total area, patch size, and habitat permanence. Almost all of the species (n = 24) experienced negative habitat changes due to SLR as measured by at least one of the metrics. Salt marsh and ocean beach habitats experienced the most change (out of 16 categorical land cover types) across the three metrics and species that used salt marsh extensively (rails and marsh sparrows) were ranked highest for exposure to habitat changes. Species that nested on ocean beaches (Diamondback Terrapins, shorebirds, and terns) were also ranked highly, but their use of other foraging habitats reduced their overall exposure. Future studies on potential effects of SLR on vertebrates in southeastern coastal ecosystems should focus on the relative importance of different habitat types to these species’ foraging and nesting requirements. Our straightforward prioritization approach is applicable to other coastal systems and can provide insight to managers on which species to focus resources, what components of their habitats need to be protected, and which locations in the study area will provide habitat refuges in the face of SLR.

  7. Do lower vertebrates suffer from motion sickness?

    NASA Astrophysics Data System (ADS)

    Lychakov, Dmitri

    The poster presents literature data and results of the author’s studies with the goal to find out whether the lower animals are susceptible to motion sickness (Lychakov, 2012). In our studies, fish and amphibians were tested for 2 h and more by using a rotating device (f = 0.24 Hz, a _{centrifugal} = 0.144 g) and a parallel swing (f = 0.2 Hz, a _{horizontal} = 0.059 g). The performed studies did not revealed in 4 fish species and in toads any characteristic reactions of the motion sickness (sopite syndrome, prodromal preparatory behavior, vomiting). At the same time, in toads there appeared characteristic stress reactions (escape response, an increase of the number of urinations, inhibition of appetite), as well as some other reactions not associated with motion sickness (regular head movements, eye retractions). In trout fry the used stimulation promoted division of the individuals into the groups differing by locomotor reaction to stress, as well as the individuals with the well-expressed compensatory reaction that we called the otolithotropic reaction. Analysis of results obtained by other authors confirms our conclusions. Thus, the lower vertebrates, unlike mammals, are immune to motion sickness either under the land conditions or under conditions of weightlessness. On the basis of available experimental data and theoretical concepts of mechanisms of development the motion sickness, formulated in several hypotheses (mismatch hypothesis, Traisman‘ s hypothesis, resonance hypothesis), there presented the synthetic hypothesis of motion sickness that has the conceptual significance. According to the hypothesis, the unusual stimulation producing sensor-motor or sensor-sensor conflict or an action of vestibular and visual stimuli of frequency of about 0.2 Hz is perceived by CNS as poisoning and causes the corresponding reactions. The motion sickness actually is a byproduct of technical evolution. It is suggested that in the lower vertebrates, unlike mammals

  8. Contaminant effect endpoints in terrestrial vertebrates at and above the individual level

    USGS Publications Warehouse

    Rattner, B.A.; Cohen, J.B.; Golden, N.H.

    2000-01-01

    Use of biochemical, physiological, anatomical, reproductive and behavioral characteristics of wild terrestrial vertebrates to assess contaminant exposure and effects has become commonplace over the past 3 decades. At the level of the individual organism, response patterns have been associated with and sometimes causally linked to contaminant exposure. However, such responses at the organismal level are rarely associated with or causally linked to effects at the population level. Although the ultimate goal of ecotoxicology is the protection of populations, communities, and ecosystems, most of the existing science and regulatory legislation focus on the level of the individual. Consequently, much of this overview concentrates on contaminant effects at the organismal level, with some extrapolation to higher-level effects. In this chapter, we review the state of the science for the evaluation of biotic end-points used to assess contaminant exposure and effects at or above the level of the individual. In addition, we describe extant contaminant concentration thresholds, guidelines, or standards (toxicant criteria) in environmental matrices (e.g., water, soil, sediment, foods) that have been developed to protect wild terrestrial vertebrates. Suggestions are provided to develop and embellish the use and value of such endpoints and criteria for extrapolation of effects to higher levels of biological organization. Increasing focus on populations, communities, and ecosystems is needed to develop biologically meaningful regulatory guidelines that will protect natural resources.

  9. 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. PMID:23746908

  10. Fatal Vertebral Artery Injury in Penetrating Cervical Spine Trauma

    PubMed Central

    Tannoury, Chadi; Degiacomo, Anthony

    2015-01-01

    Study Design. This case illustrates complications to a vertebral artery injury (VAI) resulting from penetrating cervical spine trauma. Objectives. To discuss the management of both VAI and cervical spine trauma after penetrating gunshot wound to the neck. Summary of Background Data. Vertebral artery injury following cervical spine trauma is infrequent, and a unilateral VAI often occurs without neurologic sequela. Nevertheless, devastating complications of stroke and death do occur. Methods. A gunshot wound to the neck resulted in a C6 vertebral body fracture and C5–C7 transverse foramina fractures. Neck CT angiogram identified a left vertebral artery occlusion. A cerebral angiography confirmed occlusion of the left extracranial vertebral artery and patency of the remaining cerebrovascular system. Following anterior cervical corpectomy and stabilization, brainstem infarction occurred and resulted in death. Results. A fatal outcome resulted from vertebral artery thrombus propagation with occlusion of the basilar artery triggering basilar ischemia and subsequent brainstem and cerebellar infarction. Conclusions. Vertebral artery injury secondary to cervical spine trauma can lead to potentially devastating neurologic sequela. Early surgical stabilization, along with anticoagulation therapy, contributes towards managing the combination of injuries. Unfortunately, despite efforts, a poor outcome is sometimes inevitable when cervical spine trauma is coupled with a VAI. PMID:26640731

  11. Thyroglobulin Represents a Novel Molecular Architecture of Vertebrates.

    PubMed

    Holzer, Guillaume; Morishita, Yoshiaki; Fini, Jean-Baptiste; Lorin, Thibault; Gillet, Benjamin; Hughes, Sandrine; Tohmé, Marie; Deléage, Gilbert; Demeneix, Barbara; Arvan, Peter; Laudet, Vincent

    2016-08-01

    Thyroid hormones modulate not only multiple functions in vertebrates (energy metabolism, central nervous system function, seasonal changes in physiology, and behavior) but also in some non-vertebrates where they control critical post-embryonic developmental transitions such as metamorphosis. Despite their obvious biological importance, the thyroid hormone precursor protein, thyroglobulin (Tg), has been experimentally investigated only in mammals. This may bias our view of how thyroid hormones are produced in other organisms. In this study we searched genomic databases and found Tg orthologs in all vertebrates including the sea lamprey (Petromyzon marinus). We cloned a full-size Tg coding sequence from western clawed frog (Xenopus tropicalis) and zebrafish (Danio rerio). Comparisons between the representative mammal, amphibian, teleost fish, and basal vertebrate indicate that all of the different domains of Tg, as well as Tg regional structure, are conserved throughout the vertebrates. Indeed, in Xenopus, zebrafish, and lamprey Tgs, key residues, including the hormonogenic tyrosines and the disulfide bond-forming cysteines critical for Tg function, are well conserved despite overall divergence of amino acid sequences. We uncovered upstream sequences that include start codons of zebrafish and Xenopus Tgs and experimentally proved that these are full-length secreted proteins, which are specifically recognized by antibodies against rat Tg. By contrast, we have not been able to find any orthologs of Tg among non-vertebrate species. Thus, Tg appears to be a novel protein elaborated as a single event at the base of vertebrates and virtually unchanged thereafter. PMID:27311711

  12. A unified anatomy ontology of the vertebrate skeletal system.

    PubMed

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

    2012-01-01

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

  13. A Unified Anatomy Ontology of the Vertebrate Skeletal System

    PubMed Central

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

    2012-01-01

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

  14. Observer agreement in pediatric semi-quantitative vertebral fracture diagnosis

    PubMed Central

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

    2013-01-01

    Background The Genant semi-quantitative (GSQ) method has been a standard procedure for diagnosis of vertebral fractures in adults, but has only recently been shown to be of clinical utility in pediatrics. Observer agreement using the GSQ method in this age group has not been described. Objective To evaluate observer agreement on vertebral readability and vertebral fracture diagnosis using the GSQ method in pediatric vertebral morphometry. Materials and methods Spine radiographs of 186 children with acute lymphoblastic leukemia were evaluated independently by three radiologists using the same GSQ methodology as in adults. A subset of 100 radiographs was evaluated on two occasions. Results An average of 4.7% of vertebrae were unreadable for the three radiologists. Intraobserver Cohen’s kappa (κ) on readability ranged from 0.434 to 0.648 at the vertebral level and from 0.416 to 0.611 at the patient level, while interobserver κ for readability had a range of 0.330 to 0.504 at the vertebral level and 0.295 to 0.467 at the patient level. Intraobserver κ for the presence of vertebral fracture had a range of 0.529 to 0.726 at the vertebral level and was 0.528 to 0.767 at the patient level. Interobserver κ for fracture at the vertebral level ranged from 0.455 to 0.548 and from 0.433 to 0.486 at the patient level. Conclusion Most κ values for both intra- and interobserver agreement in applying the GSQ method to pediatric spine radiographs were in the moderate to substantial range, comparable to the performance of the technique in adult studies. The GSQ method should be considered for use in pediatric research and clinical practice. PMID:24323185

  15. Gut Melatonin in Vertebrates: Chronobiology and Physiology

    PubMed Central

    Mukherjee, Sourav; Maitra, Saumen Kumar

    2015-01-01

    Melatonin, following discovery in the bovine pineal gland, has been detected in several extra-pineal sources including gastrointestinal tract or gut. Arylalkylamine N-acetyltransferase (AANAT) is the key regulator of its biosynthesis. Melatonin in pineal is rhythmically produced with a nocturnal peak in synchronization with environmental light–dark cycle. A recent study on carp reported first that melatonin levels and intensity of a ~23 kDa AANAT protein in each gut segment also exhibit significant daily variations but, unlike pineal, show a peak at midday in all seasons. Extensive experimental studies ruled out direct role of light–dark conditions in determining temporal pattern of gut melatoninergic system in carp, and opened up possible role of environmental non-photic cue(s) as its synchronizer. Based on mammalian findings, physiological significance of gut-derived melatonin also appears unique because its actions at local levels sharing paracrine and/or autocrine functions have been emphasized. The purpose of this mini review is to summarize the existing data on the chronobiology and physiology of gut melatonin and to emphasize their relation with the same hormone derived in the pineal in vertebrates including fish. PMID:26257705

  16. Earth orbital variations and vertebrate bioevolution

    NASA Technical Reports Server (NTRS)

    Mclean, Dewey M.

    1988-01-01

    Cause of the Pleistocene-Holocene transition mammalian extinctions at the end of the last age is the subject of debate between those advocating human predation and climate change. Identification of an ambient air temperature (AAT)-uterine blood flow (UBF) coupling phenomenon supports climate change as a factor in the extinctions, and couples the extinctions to earth orbital variations that drive ice age climatology. The AAT-UBF phenomenon couples mammalian bioevolution directly to climate change via effects of environmental heat upon blood flow to the female uterus and damage to developing embryos. Extinctions were in progress during climatic warming before the Younger Dryas event, and after, at times when the AAT-UBF couple would have been operative; however, impact of a sudden short-term cooling on mammals in the process of adapting to smaller size and relatively larger S/V would have been severe. Variations in earth's orbit, and orbital forcing of atmospheric CO2 concentrations, were causes of the succession of Pleistocene ice ages. Coincidence of mammalian extinctions with terminations of the more intense cold stages links mammalian bioevolution to variations in earth's orbit. Earth orbital variations are a driving source of vertebrate bioevolution.

  17. Mathematical modeling of vertebrate limb development.

    PubMed

    Zhang, Yong-Tao; Alber, Mark S; Newman, Stuart A

    2013-05-01

    In this paper, we review the major mathematical and computational models of vertebrate limb development and their roles in accounting for different aspects of this process. The main aspects of limb development that have been modeled include outgrowth and shaping of the limb bud, establishment of molecular gradients within the bud, and formation of the skeleton. These processes occur interdependently during development, although (as described in this review), there are various interpretations of the biological relationships among them. A wide range of mathematical and computational methods have been used to study these processes, including ordinary and partial differential equation systems, cellular automata and discrete, stochastic models, finite difference methods, finite element methods, the immersed boundary method, and various combinations of the above. Multiscale mathematical modeling and associated computational simulation have become integrated into the study of limb morphogenesis and pattern formation to an extent with few parallels in the field of developmental biology. These methods have contributed to the design and analysis of experiments employing microsurgical and genetic manipulations, evaluation of hypotheses for limb bud outgrowth, interpretation of the effects of natural mutations, and the formulation of scenarios for the origination and evolution of the limb skeleton. PMID:23219575

  18. Microtubules, polarity and vertebrate neural tube morphogenesis.

    PubMed

    Cearns, Michael D; Escuin, Sarah; Alexandre, Paula; Greene, Nicholas D E; Copp, Andrew J

    2016-07-01

    Microtubules (MTs) are key cellular components, long known to participate in morphogenetic events that shape the developing embryo. However, the links between the cellular functions of MTs, their effects on cell shape and polarity, and their role in large-scale morphogenesis remain poorly understood. Here, these relationships were examined with respect to two strategies for generating the vertebrate neural tube: bending and closure of the mammalian neural plate; and cavitation of the teleost neural rod. The latter process has been compared with 'secondary' neurulation that generates the caudal spinal cord in mammals. MTs align along the apico-basal axis of the mammalian neuroepithelium early in neural tube closure, participating functionally in interkinetic nuclear migration, which indirectly impacts on cell shape. Whether MTs play other functional roles in mammalian neurulation remains unclear. In the zebrafish, MTs are important for defining the neural rod midline prior to its cavitation, both by localizing apical proteins at the tissue midline and by orienting cell division through a mirror-symmetric MT apparatus that helps to further define the medial localization of apical polarity proteins. Par proteins have been implicated in centrosome positioning in neuroepithelia as well as in the control of polarized morphogenetic movements in the neural rod. Understanding of MT functions during early nervous system development has so far been limited, partly by techniques that fail to distinguish 'cause' from 'effect'. Future developments will likely rely on novel ways to selectively impair MT function in order to investigate the roles they play. PMID:27025884

  19. Blurring the Edges in Vertebrate Sex Determination

    PubMed Central

    Barske, Lindsey A.

    2009-01-01

    Summary of recent advances Sex in vertebrates is determined by genetic- or environmentally-based signals. These signals initiate molecular cascades and cell-cell interactions within the gonad that lead to the adoption of the male or female fate. Previously, genetic- and environmentally-based mechanisms were thought to be distinct, but this idea is fading as a result of the unexpected discovery of coincident genetic and thermal influences within single species. Together with accumulating phylogenetic evidence of frequent transitions between sex-determining mechanisms, these findings suggest that genetic and environmental sex determination actually represent points on a continuum rather than discrete categories, and that populations may shift in one direction or the other in response to mutations or changing ecological conditions. Elucidation of the underlying molecular basis of sex determination in mice has yielded a bistable model of mutually antagonistic signaling pathways and feedback regulatory loops. This system would be highly responsive to changes in the upstream primary signal and may provide a basis for the rapid evolution of and transitions between different methods of sex determination. PMID:19152784

  20. Evolution and development of the vertebrate ear

    NASA Technical Reports Server (NTRS)

    Fritzsch, B.; Beisel, K. W.

    2001-01-01

    This review outlines major aspects of development and evolution of the ear, specifically addressing issues of cell fate commitment and the emerging molecular governance of these decisions. Available data support the notion of homology of subsets of mechanosensors across phyla (proprioreceptive mechanosensory neurons in insects, hair cells in vertebrates). It is argued that this conservation is primarily related to the specific transducing environment needed to achieve mechanosensation. Achieving this requires highly conserved transcription factors that regulate the expression of the relevant structural genes for mechanosensory transduction. While conserved at the level of some cell fate assignment genes (atonal and its mammalian homologue), the ear has also radically reorganized its development by implementing genes used for cell fate assignment in other parts of the developing nervous systems (e.g., neurogenin 1) and by evolving novel sets of genes specifically associated with the novel formation of sensory neurons that contact hair cells (neurotrophins and their receptors). Numerous genes have been identified that regulate morphogenesis, but there is only one common feature that emerges at the moment: the ear appears to have co-opted genes from a large variety of other parts of the developing body (forebrain, limbs, kidneys) and establishes, in combination with existing transcription factors, an environment in which those genes govern novel, ear-related morphogenetic aspects. The ear thus represents a unique mix of highly conserved developmental elements combined with co-opted and newly evolved developmental elements.

  1. Cell death in the developing vertebrate retina.

    PubMed

    Vecino, Elena; Hernández, María; García, Mónica

    2004-01-01

    Programmed cell death occurs naturally, as a physiological process, during the embryonic development of multicellular organisms. In the retina, which belongs to the central nervous system, at least two phases of cell death have been reported to occur during development. An early phase takes place concomitant with the processes of neurogenesis, cell migration and cell differentiation. A later phase affecting mainly neurons occurs when connections are established and synapses are formed, resulting in selective elimination of inappropriate connections. This pattern of cell death in the developing retina is common among different vertebrates. However, the timing and magnitude of retinal cell death varies among species. In addition, a precise regulation of apoptosis during retinal development has been described. Factors such as neurotrophins, among many others, and electrical activity influence the survival of retinal cells during the course of development. In this paper, we present a summary of these different aspects of programmed cell death during retinal development, and examine how these differ among different species. PMID:15558487

  2. Animal Models of Parkinson's Disease: Vertebrate Genetics

    PubMed Central

    Lee, Yunjong; Dawson, Valina L.; Dawson, Ted M.

    2012-01-01

    Parkinson's disease (PD) is a complex genetic disorder that is associated with environmental risk factors and aging. Vertebrate genetic models, especially mice, have aided the study of autosomal-dominant and autosomal-recessive PD. Mice are capable of showing a broad range of phenotypes and, coupled with their conserved genetic and anatomical structures, provide unparalleled molecular and pathological tools to model human disease. These models used in combination with aging and PD-associated toxins have expanded our understanding of PD pathogenesis. Attempts to refine PD animal models using conditional approaches have yielded in vivo nigrostriatal degeneration that is instructive in ordering pathogenic signaling and in developing therapeutic strategies to cure or halt the disease. Here, we provide an overview of the generation and characterization of transgenic and knockout mice used to study PD followed by a review of the molecular insights that have been gleaned from current PD mouse models. Finally, potential approaches to refine and improve current models are discussed. PMID:22960626

  3. Vertebral heart size in retired racing Greyhounds.

    PubMed

    Marin, Liliana M; Brown, Jamie; McBrien, Chas; Baumwart, Ryan; Samii, Valerie F; Couto, C Guillermo

    2007-01-01

    The vertebral heart size (VHS) is used to objectively assess cardiac dimensions on thoracic radiographs. A high VHS suggest the presence of cardiac pathology, such as dilated cardiomyopathy, degenerative atrioventricular valvular disease, pericardial effusion, pericardioperitoneal diaphragmatic hernia, tricuspid dysplasia, ventricular septal defect, or patent ductus arteriosus, among others. However, breed or body conformation can influence the VHS. Because Greyhounds have a high prevalence of physiologic systolic murmurs associated with high aortic velocity, and large cardiac dimensions when compared with dogs of similar size, they are frequently suspected of having heart disease. The purpose of this study was to compare the VHS in normal Greyhounds with those in Rottweilers, and a group of dogs from various other breeds using both analog and digital radiology. The VHS was significantly higher in Greyhounds (P< 0.0001), when compared with Rottweilers and to other dog breeds. The mean VHS on lateral radiographs for Greyhounds was 10.5 +/- 0.1, for Rottweilers it was 9.8 +/- 0.1, and for mixed breed dogs it was 10.1 +/- 0.2. This study confirms that the relative cardiomegaly reported in necropsy and echocardiographic studies in Greyhounds is easily detected using plain radiography and the VHS. PMID:17691632

  4. Evolution of the Vertebrate Resistin Gene Family

    PubMed Central

    Hu, Qingda; Tan, Huanran; Irwin, David M.

    2015-01-01

    Resistin (encoded by Retn) was previously identified in rodents as a hormone associated with diabetes; however human resistin is instead linked to inflammation. Resistin is a member of a small gene family that includes the resistin-like peptides (encoded by Retnl genes) in mammals. Genomic searches of available genome sequences of diverse vertebrates and phylogenetic analyses were conducted to determine the size and origin of the resistin-like gene family. Genes encoding peptides similar to resistin were found in Mammalia, Sauria, Amphibia, and Actinistia (coelacanth, a lobe-finned fish), but not in Aves or fish from Actinopterygii, Chondrichthyes, or Agnatha. Retnl originated by duplication and transposition from Retn on the early mammalian lineage after divergence of the platypus, but before the placental and marsupial mammal divergence. The resistin-like gene family illustrates an instance where the locus of origin of duplicated genes can be identified, with Retn continuing to reside at this location. Mammalian species typically have a single copy Retn gene, but are much more variable in their numbers of Retnl genes, ranging from 0 to 9. Since Retn is located at the locus of origin, thus likely retained the ancestral expression pattern, largely maintained its copy number, and did not display accelerated evolution, we suggest that it is more likely to have maintained an ancestral function, while Retnl, which transposed to a new location, displays accelerated evolution, and shows greater variability in gene number, including gene loss, likely evolved new, but potentially lineage-specific, functions. PMID:26076481

  5. Evolution of the Vertebrate Resistin Gene Family.

    PubMed

    Hu, Qingda; Tan, Huanran; Irwin, David M

    2015-01-01

    Resistin (encoded by Retn) was previously identified in rodents as a hormone associated with diabetes; however human resistin is instead linked to inflammation. Resistin is a member of a small gene family that includes the resistin-like peptides (encoded by Retnl genes) in mammals. Genomic searches of available genome sequences of diverse vertebrates and phylogenetic analyses were conducted to determine the size and origin of the resistin-like gene family. Genes encoding peptides similar to resistin were found in Mammalia, Sauria, Amphibia, and Actinistia (coelacanth, a lobe-finned fish), but not in Aves or fish from Actinopterygii, Chondrichthyes, or Agnatha. Retnl originated by duplication and transposition from Retn on the early mammalian lineage after divergence of the platypus, but before the placental and marsupial mammal divergence. The resistin-like gene family illustrates an instance where the locus of origin of duplicated genes can be identified, with Retn continuing to reside at this location. Mammalian species typically have a single copy Retn gene, but are much more variable in their numbers of Retnl genes, ranging from 0 to 9. Since Retn is located at the locus of origin, thus likely retained the ancestral expression pattern, largely maintained its copy number, and did not display accelerated evolution, we suggest that it is more likely to have maintained an ancestral function, while Retnl, which transposed to a new location, displays accelerated evolution, and shows greater variability in gene number, including gene loss, likely evolved new, but potentially lineage-specific, functions. PMID:26076481

  6. Facultative parthenogenesis discovered in wild vertebrates

    PubMed Central

    Booth, Warren; Smith, Charles F.; Eskridge, Pamela H.; Hoss, Shannon K.; Mendelson, Joseph R.; Schuett, Gordon W.

    2012-01-01

    Facultative parthenogenesis (FP)—asexual reproduction by bisexual species—has been documented in a variety of multi-cellular organisms but only recently in snakes, varanid lizards, birds and sharks. Unlike the approximately 80 taxa of unisexual reptiles, amphibians and fishes that exist in nature, FP has yet to be documented in the wild. Based on captive documentation, it appears that FP is widespread in squamate reptiles (snakes, lizards and amphisbaenians), and its occurrence in nature seems inevitable, yet the task of detecting FP in wild individuals has been deemed formidable. Here we show, using microsatellite DNA genotyping and litter characteristics, the first cases of FP in wild-collected pregnant females and their offspring of two closely related species of North American pitviper snakes—the copperhead (Agkistrodon contortrix) and cottonmouth (Agkistrodon piscivorus). Our findings support the view that non-hybrid origins of parthenogenesis, such as FP, are more common in squamates than previously thought. With this confirmation, FP can no longer be viewed as a rare curiosity outside the mainstream of vertebrate evolution. Future research on FP in squamate reptiles related to proximate control of induction, reproductive competence of parthenogens and population genetics modelling is warranted. PMID:22977071

  7. Decay of vertebrate characters in hagfish and lamprey (Cyclostomata) and the implications for the vertebrate fossil record

    PubMed Central

    Sansom, Robert S.; Gabbott, Sarah E.; Purnell, Mark A.

    2011-01-01

    The timing and sequence of events underlying the origin and early evolution of vertebrates remains poorly understood. The palaeontological evidence should shed light on these issues, but difficulties in interpretation of the non-biomineralized fossil record make this problematic. Here we present an experimental analysis of decay of vertebrate characters based on the extant jawless vertebrates (Lampetra and Myxine). This provides a framework for the interpretation of the anatomy of soft-bodied fossil vertebrates and putative cyclostomes, and a context for reading the fossil record of non-biomineralized vertebrate characters. Decay results in transformation and non-random loss of characters. In both lamprey and hagfish, different types of cartilage decay at different rates, resulting in taphonomic bias towards loss of ‘soft’ cartilages containing vertebrate-specific Col2α1 extracellular matrix proteins; phylogenetically informative soft-tissue characters decay before more plesiomorphic characters. As such, synapomorphic decay bias, previously recognized in early chordates, is more pervasive, and needs to be taken into account when interpreting the anatomy of any non-biomineralized fossil vertebrate, such as Haikouichthys, Mayomyzon and Hardistiella. PMID:20947532

  8. The effect of teriparatide to alleviate pain and to prevent vertebral collapse after fresh osteoporotic vertebral fracture.

    PubMed

    Tsuchie, Hiroyuki; Miyakoshi, Naohisa; Kasukawa, Yuji; Nishi, Tomio; Abe, Hidekazu; Segawa, Toyohito; Shimada, Yoichi

    2016-01-01

    Vertebral fracture is often seen in osteoporotic patients. Teriparatide is expected to promote bone union. Therefore, we evaluated the action of vertebral collapse prevention by administering teriparatide to vertebral fracture patients. Thirty-four patients with fresh vertebral fracture (48 vertebrae) participated in this study. They were administered either teriparatide (daily 20 µg/day or weekly 56.5 µg/week) or risedronate (17.5 mg/week): ten patients (20 vertebrae) received teriparatide daily (Daily group), 11 patients (15 vertebrae) received teriparatide weekly (Weekly group), and 13 patients (14 vertebrae) received risedronate (RIS group). We compared some laboratory examination items, visual analogue scale (VAS) of low back pain, vertebral collapse rate and local kyphotic angle, and the cleft frequency. In addition, we evaluated 22 vertebral fracture patients (24 vertebrae) who did not take any osteoporotic medicines (Control group). There was no significant difference in any of the scores at the start of treatment. At 8 and 12 weeks after the initial visit, VAS scores in the Daily and Weekly groups were significantly lower than in the RIS group (p < 0.05). At 8 and 12 weeks, the vertebral collapse rate and local kyphotic angle in the Daily group were significantly lower than in the RIS and Control groups (p < 0.01 and p < 0.05, respectively), and those in the Weekly group were significantly lower than in the Control group (p < 0.05). The cleft frequency in the Daily group was significantly lower than in the RIS group (p < 0.05). Teriparatide is promising for the prevention of vertebral collapse progression after vertebral fracture. PMID:25773046

  9. Understanding Balloon Kyphoplasty and Myeloma-Induced Vertebral Compression Fractures

    MedlinePlus

    ... back and the ribs. More often than not, back pain and generalized weakness are what bring many undiagnosed ... the doctor in the first place. Sudden severe back pain can indicate that the vertebral body *Words appearing ...

  10. GENETIC VARIATION IN CLONAL VERTEBRATES DETECTED BY SIMPLE SEQUENCE FINGERPRINTING

    EPA Science Inventory

    Measurement of clonal heterogeneity is central to understanding evolutionary and population genetics of roughly 50 species of vertebrates lack effective genetic recombination. imple-sequence DNA fingerprinting with oligonucleotide probes (CAG)5 and (GACA)4 was used to detect hete...

  11. Relevant signs of stable and unstable thoracolumbar vertebral column trauma

    SciTech Connect

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

    1981-12-01

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

  12. Explaining large-scale patterns of vertebrate diversity

    PubMed Central

    Wiens, John J.

    2015-01-01

    The major clades of vertebrates differ dramatically in their current species richness, from 2 to more than 32 000 species each, but the causes of this variation remain poorly understood. For example, a previous study noted that vertebrate clades differ in their diversification rates, but did not explain why they differ. Using a time-calibrated phylogeny and phylogenetic comparative methods, I show that most variation in diversification rates among 12 major vertebrate clades has a simple ecological explanation: predominantly terrestrial clades (i.e. birds, mammals, and lizards and snakes) have higher net diversification rates than predominantly aquatic clades (i.e. amphibians, crocodilians, turtles and all fish clades). These differences in diversification rates are then strongly related to patterns of species richness. Habitat may be more important than other potential explanations for richness patterns in vertebrates (such as climate and metabolic rates) and may also help explain patterns of species richness in many other groups of organisms. PMID:26202428

  13. A Common Fold Mediates Vertebrate Defense and Bacterial Attack

    SciTech Connect

    Rosado, Carlos J.; Buckle, Ashley M.; Law, Ruby H.P.; Butcher, Rebecca E.; Kan, Wan-Ting; Bird, Catherina H.; Ung, Kheng; Browne, Kylie A.; Baran, Katherine; Bashtannyk-Puhalovich, Tanya A.; Faux, Noel G.; Wong, Wilson; Porter, Corrine J.; Pike, Robert N.; Ellisdon, Andrew M.; Pearce, Mary C.; Bottomley, Stephen P.; Emsley, Jonas; Smith, A. Ian; Rossjohn, Jamie; Hartland, Elizabeth L.; Voskoboinik, Ilia; Trapani, Joseph A.; Bird, Phillip I.; Dunstone, Michelle A.; Whisstock, James C.

    2008-10-02

    Proteins containing membrane attack complex/perforin (MACPF) domains play important roles in vertebrate immunity, embryonic development, and neural-cell migration. In vertebrates, the ninth component of complement and perforin form oligomeric pores that lyse bacteria and kill virus-infected cells, respectively. However, the mechanism of MACPF function is unknown. We determined the crystal structure of a bacterial MACPF protein, Plu-MACPF from Photorhabdus luminescens, to 2.0 angstrom resolution. The MACPF domain reveals structural similarity with poreforming cholesterol-dependent cytolysins (CDCs) from Gram-positive bacteria. This suggests that lytic MACPF proteins may use a CDC-like mechanism to form pores and disrupt cell membranes. Sequence similarity between bacterial and vertebrate MACPF domains suggests that the fold of the CDCs, a family of proteins important for bacterial pathogenesis, is probably used by vertebrates for defense against infection.

  14. Do Vertebrate Gut Metagenomes Confer Rapid Ecological Adaptation?

    PubMed

    Alberdi, Antton; Aizpurua, Ostaizka; Bohmann, Kristine; Zepeda-Mendoza, Marie Lisandra; Gilbert, M Thomas P

    2016-09-01

    During times of rapid environmental change, survival of most vertebrate populations depends on their phenomic plasticity. Although differential gene-expression and post-transcriptional processes of the host genome receive focus as the main molecular mechanisms, growing evidence points to the gut microbiota as a key driver defining hosts' phenotypes. We propose that the plasticity of the gut microbiota might be an essential factor determining phenomic plasticity of vertebrates, and that it might play a pivotal role when vertebrates acclimate and adapt to fast environmental variation. We contemplate some key questions and suggest methodological approaches and experimental designs that can be used to evaluate whether gut microorganisms provide a boost of plasticity to vertebrates' phenomes, thereby increasing their acclimation and adaptation capacity. PMID:27453351

  15. Experiment K307: Vertebral body strength of rat spinal columns

    NASA Technical Reports Server (NTRS)

    Kazarian, L. E.

    1981-01-01

    The effects of space flight on vertebral body bone strength excised were investigated. Comparative biomechanical investigations of vertebral body strength for flight, synchronous, and vivarium rats following spacecraft recovery (R+0), at R+6 and R+29 days post flight recovery are presented. Statistical analyses are presented for the mechanical properties of stiffness, ultimate load, displacement to ultimate load, and energy to ultimate load. At R+0 all of the above properties show that the vertebral body exhibits an increasing susceptibility to fracture. The reduction of bone strength is inhomogeneous and dependent on vertebral level. The R+6 recovery data was inconclusive since it varied above and below the R+0 data. At R+29 ultimate load values showed a statistically significant increase in bone strength approaching that of the vivarium or control group.

  16. The evolutionary landscape of alternative splicing in vertebrate species.

    PubMed

    Barbosa-Morais, Nuno L; Irimia, Manuel; Pan, Qun; Xiong, Hui Y; Gueroussov, Serge; Lee, Leo J; Slobodeniuc, Valentina; Kutter, Claudia; Watt, Stephen; Colak, Recep; Kim, TaeHyung; Misquitta-Ali, Christine M; Wilson, Michael D; Kim, Philip M; Odom, Duncan T; Frey, Brendan J; Blencowe, Benjamin J

    2012-12-21

    How species with similar repertoires of protein-coding genes differ so markedly at the phenotypic level is poorly understood. By comparing organ transcriptomes from vertebrate species spanning ~350 million years of evolution, we observed significant differences in alternative splicing complexity between vertebrate lineages, with the highest complexity in primates. Within 6 million years, the splicing profiles of physiologically equivalent organs diverged such that they are more strongly related to the identity of a species than they are to organ type. Most vertebrate species-specific splicing patterns are cis-directed. However, a subset of pronounced splicing changes are predicted to remodel protein interactions involving trans-acting regulators. These events likely further contributed to the diversification of splicing and other transcriptomic changes that underlie phenotypic differences among vertebrate species. PMID:23258890

  17. An amphioxus Krox gene: insights into vertebrate hindbrain evolution.

    PubMed

    Knight, R D; Panopoulou, G D; Holland, P W; Shimeld, S M

    2000-10-01

    The transcription factor Krox-20 has roles in the maintenance of segmentation and specification of segment identity in the vertebrate hindbrain. Overt hindbrain segmentation is a vertebrate novelty, and is not seen in invertebrate chordates such as amphioxus and tunicates. To test if the roles of Krox-20 are also derived, we cloned a Krox-20 related gene, AmphiKrox, from amphioxus. AmphiKrox is related to a small family of vertebrate Krox genes and is expressed in the most anterior region of the amphioxus brain and in the club shaped gland, a secretory organ that develops in the anterior pharynx. Neither expression domain overlaps with the expression of AmphiHox-1, -2, -3 or -4, suggesting that the roles of Krox-20 in hindbrain segmentation and in Hox gene regulation were acquired concomitant with the duplication of Krox genes in vertebrate evolution. PMID:11180801

  18. [About evolution of sleep-wakefulness cycle in vertebrates].

    PubMed

    Oganesian, G A; Aristakesian, E A; Vataev, S I

    2012-10-01

    Data about behavioral, somato-vegetative and neurophysiological parameters of sleep and wakefulness in insects, cold- and warm-blooded vertebrates are provided. Hypotheses existing now about evolutionary formation of separate sleep phases and stages in vertebrates are considered. In the review are shown the data about correlations of quantitative characteristics of sleep and wake in some mammals with basic metabolic rate, lifestyle, environmental habits. The original experimental results at formation of neurophysiological characteristics of sleep and wake in vertebrates, phylogeny and in ontogeny of mature and immature mammals are provided in detail. On the basis of own concepts about evolutionary development of sleep-wakefulness cycle in vertebrates the interactions of telencephalic, diencephalic and rhombencepalic parts of brain in the processes of cycle wakefulness cycle integration are discussed. PMID:23401913

  19. Duplications of hox gene clusters and the emergence of vertebrates.

    PubMed

    Soshnikova, Natalia; Dewaele, Romain; Janvier, Philippe; Krumlauf, Robb; Duboule, Denis

    2013-06-15

    The vertebrate body plan is characterized by an increased complexity relative to that of all other chordates and large-scale gene amplifications have been associated with key morphological innovations leading to their remarkable evolutionary success. Here, we use compound full Hox clusters deletions to investigate how Hox genes duplications may have contributed to the emergence of vertebrate-specific innovations. We show that the combined deletion of HoxA and HoxB leads to an atavistic heart phenotype, suggesting that the ancestral HoxA/B cluster was co-opted to help in diversifying the complex organ in vertebrates. Other phenotypic effects observed seem to illustrate the resurgence of ancestral (plesiomorphic) features. This indicates that the duplications of Hox clusters were associated with the recruitment or formation of novel cis-regulatory controls, which were key to the evolution of many vertebrate features and hence to the evolutionary radiation of this group. PMID:23501471

  20. Case Study: Giant Cell Arteritis with Vertebral Artery Stenosis

    PubMed Central

    Daniel Chomlak, R.; Ghazanfari, Farshad; Datta, Mineesh

    2016-01-01

    In giant cell arteritis (GCA), involvement of the vertebral arteries is rare with reported rates of 3%–4% for ischemic events secondary to vertebral artery stenosis or occlusion for those patients with GCA. This case study describes a patient who initially presented with acute onset of vertigo but was also found to have transient, side-alternating upper limb neurological findings. While initial imaging showed no vascular abnormalities, it was not until GCA was eventually confirmed with a temporal artery biopsy that the initial scans were shown to have bilateral narrowing of the vertebral arteries. While rare, vertebral artery involvement is an important complication to consider in the setting of GCA due to the high rate of associated mortality, despite immunosuppressive therapy. PMID:27279753

  1. Tetrameric organization of vertebrate centromeric nucleosomes

    PubMed Central

    Dimitriadis, Emilios K.; Weber, Christian; Gill, Rajbir K.; Diekmann, Stephan; Dalal, Yamini

    2010-01-01

    Mitosis ensures equal genome segregation in the eukaryotic lineage. This process is facilitated by microtubule attachment to each chromosome via its centromere. In centromeres, canonical histone H3 is replaced in nucleosomes by a centromere-specific histone H3 variant (CENH3), providing the unique epigenetic signature required for microtubule binding. Due to recent findings of alternative CENH3 nucleosomal forms in invertebrate centromeres, it has been debated whether the classical octameric nucleosomal arrangement of two copies of CENH3, H4, H2A, and H2B forms the basis of the vertebrate centromere. To address this question directly, we examined CENH3 [centromere protein A (CENP-A)] nucleosomal organization in human cells, using a combination of nucleosome component analysis, atomic force microscopy (AFM), and immunoelectron microscopy (immuno-EM). We report that native CENP-A nucleosomes contain centromeric alpha satellite DNA, have equimolar amounts of H2A, H2B, CENP-A, and H4, and bind kinetochore proteins. These nucleosomes, when measured by AFM, yield one-half the dimensions of canonical octameric nucleosomes. Using immuno-EM, we find that one copy of CENP-A, H2A, H2B, and H4 coexist in CENP-A nucleosomes, in which internal C-terminal domains are accessible. Our observations indicate that CENP-A nucleosomes are organized as asymmetric heterotypic tetramers, rather than canonical octamers. Such altered nucleosomes form a chromatin fiber with distinct folding characteristics, which we utilize to discriminate tetramers directly within bulk chromatin. We discuss implications of our observations in the context of universal epigenetic and mechanical requirements for functional centromeres. PMID:21059934

  2. Treatment of Ruptured Vertebral Artery Dissecting Aneurysms

    PubMed Central

    Hamasaki, Osamu; Ikawa, Fusao; Hidaka, Toshikazu; Kurokawa, Yasuharu; Yonezawa, Ushio

    2014-01-01

    Summary We evaluated the outcomes of endovascular or surgical treatment of ruptured vertebral artery dissecting aneurysms (VADAs), and investigated the relations between treatment complications and the development and location of the posterior inferior cerebellar artery (PICA). We treated 14 patients (12 men, two women; mean age, 56.2 years) with ruptured VADAs between March 1999 and June 2012 at our hospital. Six and eight patients had Hunt and Hess grades 1-3 and 4-5, respectively. Twelve patients underwent internal endovascular trapping, one underwent proximal endovascular occlusion alone, and one underwent proximal endovascular occlusion in the acute stage and occipital artery (OA)-PICA anastomosis and surgical trapping in the chronic stage. The types of VADA based on their location relative to the ipsilateral PICA were distal, PICA-involved, and non-PICA in nine, two, and three patients, respectively. The types of PICA based on their development and location were bilateral anterior inferior cerebellar artery (AICA)-PICA, ipsilateral AICA-PICA, extradural, and intradural type in one, two, two, and nine patients, respectively. Two patients with high anatomical risk developed medullary infarction, but their midterm outcomes were better than in previous reports. The modified Rankin scale indicated grades 0-2, 3-5, and 6 in eight, three, and three patients, respectively. A good outcome is often obtained in the treatment of ruptured VADA using internal endovascular trapping, except in the PICA-involved type, even with high-grade subarachnoid hemorrhage. Treatment of the PICA-involved type is controversial. The anatomical location and development of PICA may be predicted by complications with postoperative medullary infarction. PMID:24976093

  3. The 'Tully monster' is a vertebrate.

    PubMed

    McCoy, Victoria E; Saupe, Erin E; Lamsdell, James C; Tarhan, Lidya G; McMahon, Sean; Lidgard, Scott; Mayer, Paul; Whalen, Christopher D; Soriano, Carmen; Finney, Lydia; Vogt, Stefan; Clark, Elizabeth G; Anderson, Ross P; Petermann, Holger; Locatelli, Emma R; Briggs, Derek E G

    2016-04-28

    Problematic fossils, extinct taxa of enigmatic morphology that cannot be assigned to a known major group, were once a major issue in palaeontology. A long-favoured solution to the 'problem of the problematica', particularly the 'weird wonders' of the Cambrian Burgess Shale, was to consider them representatives of extinct phyla. A combination of new evidence and modern approaches to phylogenetic analysis has now resolved the affinities of most of these forms. Perhaps the most notable exception is Tullimonstrum gregarium, popularly known as the Tully monster, a large soft-bodied organism from the late Carboniferous Mazon Creek biota (approximately 309-307 million years ago) of Illinois, USA, which was designated the official state fossil of Illinois in 1989. Its phylogenetic position has remained uncertain and it has been compared with nemerteans, polychaetes, gastropods, conodonts, and the stem arthropod Opabinia. Here we review the morphology of Tullimonstrum based on an analysis of more than 1,200 specimens. We find that the anterior proboscis ends in a buccal apparatus containing teeth, the eyes project laterally on a long rigid bar, and the elongate segmented body bears a caudal fin with dorsal and ventral lobes. We describe new evidence for a notochord, cartilaginous arcualia, gill pouches, articulations within the proboscis, and multiple tooth rows adjacent to the mouth. This combination of characters, supported by phylogenetic analysis, identifies Tullimonstrum as a vertebrate, and places it on the stem lineage to lampreys (Petromyzontida). In addition to increasing the known morphological disparity of extinct lampreys, a chordate affinity for T. gregarium resolves the nature of a soft-bodied fossil which has been debated for more than 50 years. PMID:26982721

  4. Functionally conserved enhancers with divergent sequences in distant vertebrates

    SciTech Connect

    Yang, Song; Oksenberg, Nir; Takayama, Sachiko; Heo, Seok -Jin; Poliakov, Alexander; Ahituv, Nadav; Dubchak, Inna; Boffelli, Dario

    2015-10-30

    To examine the contributions of sequence and function conservation in the evolution of enhancers, we systematically identified enhancers whose sequences are not conserved among distant groups of vertebrate species, but have homologous function and are likely to be derived from a common ancestral sequence. In conclusion, our approach combined comparative genomics and epigenomics to identify potential enhancer sequences in the genomes of three groups of distantly related vertebrate species.

  5. Diabetic foot complicated by vertebral osteomyelitis and epidural abscess

    PubMed Central

    Trombetta, Maddalena; Imbriaco, Chiara; Rigolon, Riccardo; Mingolla, Lucia; Zamboni, Federica; Dal Molin, Francesca; Cioccoloni, Dario; Sanga, Viola; Bruti, Massimiliano; Brocco, Enrico; Conti, Michela; Ravenna, Giorgio; Perrone, Fabrizia; Stoico, Vincenzo; Bonora, Enzo

    2016-01-01

    Summary Vertebral osteomyelitis (or spondylodiscitis) is steadily increasing in Western countries and often results from hematogenous seeding, direct inoculation during spinal surgery, or contiguous spread from an infection in the adjacent soft tissue. We present the case of a 67-year-old white patient with type 2 diabetes who went to Hospital for high fever, back pain, and worsening of known infected ulcers in the left foot. Despite intravenous antibiotic treatment and surgical debridement of the foot infection, high fever and lower back pain continued. Bone biopsy and two consecutive blood cultures were positive for Staphylococcus aureus. A spinal magnetic resonance imaging (MRI) was performed, revealing serious osteomyelitis in L4 and L5 complicated by an epidural abscess. Contiguous or other distant focuses of infection were not identified. In this case, diabetic foot could be considered as a primary distant focus for vertebral osteomyelitis. Clinicians should consider vertebral osteomyelitis as a ‘possible’ diagnosis in patients with type 2 diabetes complicated by foot infection that is associated with fever and lower back pain. Learning points Vertebral osteomyelitis is increasing in Western countries, especially in patients with type 2 diabetes. The primary focus of infection is the genitourinary tract followed by skin, soft tissue, endocarditis, bursitis, septic arthritis, and intravascular access. Diabetic foot could be a rare primary focus of infection for vertebral osteomyelitis, and, however, vertebral osteomyelitis could be a serious, albeit rare, complication of diabetic foot. Clinicians should keep in mind the many potential complications of diabetic foot ulcerations and consider vertebral osteomyelitis as a “possible” diagnosis in patients with type 2 diabetes and foot ulcers associated with nonspecific symptoms such as lower back pain. Early diagnosis and correct management of vertebral osteomyelitis are crucial to improve clinical outcomes

  6. The pre-vertebrate origins of neurogenic placodes.

    PubMed

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

    2015-08-27

    The sudden appearance of the neural crest and neurogenic placodes in early branching vertebrates has puzzled biologists for over a century. These embryonic tissues contribute to the development of the cranium and associated sensory organs, which were crucial for the evolution of the vertebrate "new head". A previous study suggests that rudimentary neural crest cells existed in ancestral chordates. However, the evolutionary origins of neurogenic placodes have remained obscure owing to a paucity of embryonic data from tunicates, the closest living relatives to those early vertebrates. Here we show that the tunicate Ciona intestinalis exhibits a proto-placodal ectoderm (PPE) that requires inhibition of bone morphogenetic protein (BMP) and expresses the key regulatory determinant Six1/2 and its co-factor Eya, a developmental process conserved across vertebrates. The Ciona PPE is shown to produce ciliated neurons that express genes for gonadotropin-releasing hormone (GnRH), a G-protein-coupled receptor for relaxin-3 (RXFP3) and a functional cyclic nucleotide-gated channel (CNGA), which suggests dual chemosensory and neurosecretory activities. These observations provide evidence that Ciona has a neurogenic proto-placode, which forms neurons that appear to be related to those derived from the olfactory placode and hypothalamic neurons of vertebrates. We discuss the possibility that the PPE-derived GnRH neurons of Ciona resemble an ancestral cell type, a progenitor to the complex neuronal circuit that integrates sensory information and neuroendocrine functions in vertebrates. PMID:26258298

  7. Amphioxus FGF signaling predicts the acquisition of vertebrate morphological traits

    PubMed Central

    Bertrand, Stephanie; Camasses, Alain; Somorjai, Ildiko; Belgacem, Mohamed R.; Chabrol, Olivier; Escande, Marie-Line; Pontarotti, Pierre; Escriva, Hector

    2011-01-01

    FGF signaling is one of the few cell–cell signaling pathways conserved among all metazoans. The diversity of FGF gene content among different phyla suggests that evolution of FGF signaling may have participated in generating the current variety of animal forms. Vertebrates possess the greatest number of FGF genes, the functional evolution of which may have been implicated in the acquisition of vertebrate-specific morphological traits. In this study, we have investigated the roles of the FGF signal during embryogenesis of the cephalochordate amphioxus, the best proxy for the chordate ancestor. We first isolate the full FGF gene complement and determine the evolutionary relationships between amphioxus and vertebrate FGFs via phylogenetic and synteny conservation analysis. Using pharmacological treatments, we inhibit the FGF signaling pathway in amphioxus embryos in different time windows. Our results show that the requirement for FGF signaling during gastrulation is a conserved character among chordates, whereas this signal is not necessary for neural induction in amphioxus, in contrast to what is known in vertebrates. We also show that FGF signal, acting through the MAPK pathway, is necessary for the formation of the most anterior somites in amphioxus, whereas more posterior somite formation is not FGF-dependent. This result leads us to propose that modification of the FGF signal function in the anterior paraxial mesoderm in an amphioxus-like vertebrate ancestor might have contributed to the loss of segmentation in the preotic paraxial mesoderm of the vertebrate head. PMID:21571634

  8. Violet Fox: A Clinical View of Vertebral Fractures.

    PubMed

    McKiernan, Fergus E

    2016-01-01

    Had Violet's abdominal MR not been performed, or its findings not appreciated, the cause of her clinical event might never have been known because our current concept of osteoporotic vertebral fracture (VF) is substantially predicated on a change in either vertebral height or shape on lateral or sagittal spine imaging. The intention of this commentary is to stimulate a multidisciplinary conversation of osteoporotic VFs from an integrated clinical, physiological, and imaging perspective. For research and epidemiological purposes, osteoporotic VFs have been defined as a reduction in anterior, middle, or posterior vertebral height although the required minimum height reduction (e.g., 15% or 20%) varies among definition schemes. We further classify osteoporotic VFs to be "clinical" when they are accompanied by back pain and "morphometric" when they are not, and we have generally accepted the assertion that most of the osteoporotic VFs are painless, that is, morphometric. This dichotomous VF definition scheme has been the foundation of osteoporosis epidemiology and the primary endpoint in most pivotal osteoporosis pharmaceutical trials. Although, having served the osteoporosis community well, our clinical experience, refined by recent insights into vertebral anatomy and spinal biomechanics, advances in vertebral imaging, and 2 decades of vertebral augmentation suggest that the spectrum of osteoporotic VFs is more complicated than this scheme suggests. PMID:26356546

  9. The origin of conodonts and of vertebrate mineralized skeletons

    USGS Publications Warehouse

    Murdock, Duncan J.E.; Dong, Xi-Ping; Repetski, John E.; Marone, Federica; Stampanoni, Marco; Donoghue, Philip C.J.

    2013-01-01

    Conodonts are an extinct group of jawless vertebrates whose tooth-like elements are the earliest instance of a mineralized skeleton in the vertebrate lineage, inspiring the ‘inside-out’ hypothesis that teeth evolved independently of the vertebrate dermal skeleton and before the origin of jaws. However, these propositions have been based on evidence from derived euconodonts. Here we test hypotheses of a paraconodont ancestry of euconodonts using synchrotron radiation X-ray tomographic microscopy to characterize and compare the microstructure of morphologically similar euconodont and paraconodont elements. Paraconodonts exhibit a range of grades of structural differentiation, including tissues and a pattern of growth common to euconodont basal bodies. The different grades of structural differentiation exhibited by paraconodonts demonstrate the stepwise acquisition of euconodont characters, resolving debate over the relationship between these two groups. By implication, the putative homology of euconodont crown tissue and vertebrate enamel must be rejected as these tissues have evolved independently and convergently. Thus, the precise ontogenetic, structural and topological similarities between conodont elements and vertebrate odontodes appear to be a remarkable instance of convergence. The last common ancestor of conodonts and jawed vertebrates probably lacked mineralized skeletal tissues. The hypothesis that teeth evolved before jaws and the inside-out hypothesis of dental evolution must be rejected; teeth seem to have evolved through the extension of odontogenic competence from the external dermis to internal epithelium soon after the origin of jaws.

  10. 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.

  11. Bow hunter's syndrome secondary to bilateral dynamic vertebral artery compression.

    PubMed

    Healy, Andrew T; Lee, Bryan S; Walsh, Kevin; Bain, Mark D; Krishnaney, Ajit A

    2015-01-01

    Bow hunter's syndrome is a condition in which vertebrobasilar insufficiency is resultant from head rotation, clinically manifested by presyncopal sensation, syncope, dizziness, and nausea. It is usually diagnosed clinically, with supporting vascular imaging demonstrating an occluded or at the very least compromised unilateral vertebral artery, while the dominant vertebral artery remains patent in the neutral position. Dynamic imaging is utilized to confirm the rotational compression of the dominant vertebral artery. We present the rare case of a patient with typical Bow hunter's symptoms, bilaterally patent vertebral arteries on neutral imaging, and bilateral compromise with head rotation. Our patient underwent posterior decompression of the culprit atlanto-axial transverse foramen and subaxial cervical fusion, with resolution of his symptoms. Our patient exemplifies the possibility of bilateral dynamic vertebral artery occlusion. We show that Bow hunter's syndrome cannot be ruled out in the setting of bilaterally patent vertebral arteries on neutral imaging and that severe cervical spondylosis should impart further clinical suspicion of this unusual phenomenon. PMID:25070633

  12. Osteolytic mass bridging two cervical vertebrae: Unusual presentation of a vertebral body hemangioma

    PubMed Central

    Miller, Dane; Sag, Alan Alper; Krishnan, Anant; Silbergleit, Richard; Roy, Anindya; Dulai, Mohanpal

    2015-01-01

    Vertebral hemangioma is the most common spinal axis tumor. This rare presentation of a vertebral hemangioma extended contiguously from one cervical vertebra to another, encasing the vertebral artery, and thereby mimicking other tumors of the spine. We discuss the differential diagnosis of bridging vertebral masses. PMID:27190555

  13. Targeting global protected area expansion for imperiled biodiversity.

    PubMed

    Venter, Oscar; Fuller, Richard A; Segan, Daniel B; Carwardine, Josie; Brooks, Thomas; Butchart, Stuart H M; Di Marco, Moreno; Iwamura, Takuya; Joseph, Liana; O'Grady, Damien; Possingham, Hugh P; Rondinini, Carlo; Smith, Robert J; Venter, Michelle; Watson, James E M

    2014-06-01

    Governments have agreed to expand the global protected area network from 13% to 17% of the world's land surface by 2020 (Aichi target 11) and to prevent the further loss of known threatened species (Aichi target 12). These targets are interdependent, as protected areas can stem biodiversity loss when strategically located and effectively managed. However, the global protected area estate is currently biased toward locations that are cheap to protect and away from important areas for biodiversity. Here we use data on the distribution of protected areas and threatened terrestrial birds, mammals, and amphibians to assess current and possible future coverage of these species under the convention. We discover that 17% of the 4,118 threatened vertebrates are not found in a single protected area and that fully 85% are not adequately covered (i.e., to a level consistent with their likely persistence). Using systematic conservation planning, we show that expanding protected areas to reach 17% coverage by protecting the cheapest land, even if ecoregionally representative, would increase the number of threatened vertebrates covered by only 6%. However, the nonlinear relationship between the cost of acquiring land and species coverage means that fivefold more threatened vertebrates could be adequately covered for only 1.5 times the cost of the cheapest solution, if cost efficiency and threatened vertebrates are both incorporated into protected area decision making. These results are robust to known errors in the vertebrate range maps. The Convention on Biological Diversity targets may stimulate major expansion of the global protected area estate. If this expansion is to secure a future for imperiled species, new protected areas must be sited more strategically than is presently the case. PMID:24960185

  14. Molecular signatures that are distinctive characteristics of the vertebrates and chordates and supporting a grouping of vertebrates with the tunicates.

    PubMed

    Gupta, Radhey S

    2016-01-01

    Members of the phylum Chordata and the subphylum Vertebrata are presently distinguished solely on the basis of morphological characteristics. The relationship of the vertebrates to the two non-vertebrate chordate subphyla is also a subject of debate. Analyses of protein sequences have identified multiple conserved signature indels (CSIs) that are specific for Chordata or for Vertebrata. Five CSIs in 4 important proteins are specific for the Vertebrata, whereas two other CSIs are uniquely found in all sequenced chordate species including Ciona intestinalis and Oikapleura dioica (Tunicates) as well as Branchiostoma floridae (Cephalochordates). The shared presence of these molecular signatures by all vertebrates/chordate species, but in no other animal taxa, strongly indicates that the genetic changes represented by the identified CSIs diagnose monophyletic groups. Two other discovered CSIs are uniquely shared by different vertebrate species and by either one (Ciona intestinalis) or both tunicate (Ciona and Oikapleura) species, but they are not found in Branchiostoma or other animal species. Specific presence of these CSIs in different vertebrates and either one or both tunicate species provides strong independent evidence that the vertebrate species are more closely related to the urochordates (tunicates) than to the cephalochordates. PMID:26419477

  15. Computer Simulation and Analysis on Flow Characteristics and Distribution Patterns of Polymethylmethacrylate in Lumbar Vertebral Body and Vertebral Pedicle

    PubMed Central

    Liu, Da; Liu, Xu-li; Zhang, Bo; Liao, Dong-fa; Li, Zhi-qiang; Zhou, Jiang-jun; Kang, Xia; Zheng, Wei; Lei, Wei

    2015-01-01

    This study was designed to analyze the flow and distribution of polymethylmethacrylate (PMMA) in vertebral body through computer simulation. Cadaveric lumbar vertebrae were scanned through electron beam tomography (EBT). The data was imported into Mimics software to build computational model. Vertebral body center and junction of pedicle and vertebral body were chosen as injection points. Silicone oil with viscosity of 100,000 cSt matching with PMMA bone cement was chosen for injection. The flow and distribution of silicone oil were analyzed using Fluent software. In vertebral body, silicone oil formed a circle-like shape centered by injection point on transverse and longitudinal sections, finally forming a sphere-like shape as a whole. Silicone oil diffused along lateral and posterior walls forming a circle-like shape on transverse section centered by injection point in pedicle, eventually forming a sphere-like shape as a whole. This study demonstrated that silicone oil flowed and diffused into a circle-like shape centered by injection point and finally formed a sphere-like shape as a whole in both vertebral body and pedicle. The flow and distribution of silicon oil in computational model could simulate PMMA distribution in vertebral body. It may provide theoretical evidence to reduce PMMA leakage risk during percutaneous vertebroplasty. PMID:26770969

  16. Hotspots of species richness, threat and endemism for terrestrial vertebrates in SW Europe

    NASA Astrophysics Data System (ADS)

    Pascual, López-López; Luigi, Maiorano; Alessandra, Falcucci; Emilio, Barba; Luigi, Boitani

    2011-09-01

    The Mediterranean basin, and the Iberian Peninsula in particular, represent an outstanding "hotspot" of biological diversity with a long history of integration between natural ecosystems and human activities. Using deductive distribution models, and considering both Spain and Portugal, we downscaled traditional range maps for terrestrial vertebrates (amphibians, breeding birds, mammals and reptiles) to the finest possible resolution with the data at hand, and we identified hotspots based on three criteria: i) species richness; ii) vulnerability, and iii) endemism. We also provided a first evaluation of the conservation status of biodiversity hotspots based on these three criteria considering both existing and proposed protected areas (i.e., Natura 2000). For the identification of hotspots, we used a method based on the cumulative distribution functions of species richness values. We found no clear surrogacy among the different types of hotspots in the Iberian Peninsula. The most important hotspots (considering all criteria) are located in the western and southwestern portions of the study area, in the Mediterranean biogeographical region. Existing protected areas are not specifically concentrated in areas of high species richness, with only 5.2% of the hotspots of total richness being currently protected. The Natura 2000 network can potentially constitute an important baseline for protecting vertebrate diversity in the Iberian Peninsula although further improvements are needed. We suggest taking a step forward in conservation planning in the Mediterranean basin, explicitly considering the history of the region as well as its present environmental context. This would allow moving from traditional reserve networks (conservation focused on "patterns") to considerations about the "processes" that generated present biodiversity.

  17. US protected lands mismatch biodiversity priorities.

    PubMed

    Jenkins, Clinton N; Van Houtan, Kyle S; Pimm, Stuart L; Sexton, Joseph O

    2015-04-21

    Because habitat loss is the main cause of extinction, where and how much society chooses to protect is vital for saving species. The United States is well positioned economically and politically to pursue habitat conservation should it be a societal goal. We assessed the US protected area portfolio with respect to biodiversity in the country. New synthesis maps for terrestrial vertebrates, freshwater fish, and trees permit comparison with protected areas to identify priorities for future conservation investment. Although the total area protected is substantial, its geographic configuration is nearly the opposite of patterns of endemism within the country. Most protected lands are in the West, whereas the vulnerable species are largely in the Southeast. Private land protections are significant, but they are not concentrated where the priorities are. To adequately protect the nation's unique biodiversity, we recommend specific areas deserving additional protection, some of them including public lands, but many others requiring private investment. PMID:25847995

  18. US protected lands mismatch biodiversity priorities

    PubMed Central

    Pimm, Stuart L.; Sexton, Joseph O.

    2015-01-01

    Because habitat loss is the main cause of extinction, where and how much society chooses to protect is vital for saving species. The United States is well positioned economically and politically to pursue habitat conservation should it be a societal goal. We assessed the US protected area portfolio with respect to biodiversity in the country. New synthesis maps for terrestrial vertebrates, freshwater fish, and trees permit comparison with protected areas to identify priorities for future conservation investment. Although the total area protected is substantial, its geographic configuration is nearly the opposite of patterns of endemism within the country. Most protected lands are in the West, whereas the vulnerable species are largely in the Southeast. Private land protections are significant, but they are not concentrated where the priorities are. To adequately protect the nation’s unique biodiversity, we recommend specific areas deserving additional protection, some of them including public lands, but many others requiring private investment. PMID:25847995

  19. High Serum SHBG Predicts Incident Vertebral Fractures in Elderly Men

    PubMed Central

    Vandenput, Liesbeth; Mellström, Dan; Kindmark, Andreas; Johansson, Helena; Lorentzon, Mattias; Leung, Jason; Redlund‐Johnell, Inga; Rosengren, Björn E; Karlsson, Magnus K; Wang, Yi‐Xiang; Kwok, Timothy

    2016-01-01

    ABSTRACT Previous prospective cohort studies have shown that serum levels of sex steroids and sex hormone‐binding globulin (SHBG) associate with nonvertebral fracture risk in men. The predictive value of sex hormones and SHBG for vertebral fracture risk specifically is, however, less studied. Elderly men (aged ≥65 years) from Sweden and Hong Kong participating in the Osteoporotic Fractures in Men (MrOS) study had baseline estradiol and testosterone analyzed by gas chromatography–mass spectrometry (GC‐MS) and SHBG by immunoradiometric assay (IRMA). Incident clinical vertebral fractures (n = 242 cases) were evaluated in 4324 men during an average follow‐up of 9.1 years. In a subsample of these men (n = 2256), spine X‐rays were obtained at baseline and after an average follow‐up of 4.3 years to identify incident radiographic vertebral fractures (n = 157 cases). The likelihood of incident clinical and radiographic vertebral fractures was estimated by Cox proportional hazards models and logistic regression models, respectively. Neither serum estradiol (hazard ratio [HR] per SD increase = 0.93, 95% confidence interval [CI] 0.80–1.08) nor testosterone (1.05, 0.91–1.21) predicted incident clinical vertebral fractures in age‐adjusted models in the combined data set. High serum SHBG, however, associated with increased clinical vertebral fracture risk (1.24, 1.12–1.37). This association remained significant after further adjustment for FRAX with or without bone mineral density (BMD). SHBG also associated with increased incident radiographic vertebral fracture risk (combined data set; odds ratio [OR] per SD increase = 1.23, 95% CI 1.05–1.44). This association remained significant after adjustment for FRAX with or without BMD. In conclusion, high SHBG predicts incident clinical and radiographic vertebral fractures in elderly men and adds moderate information beyond FRAX with BMD for vertebral fracture risk prediction. © 2015 The

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

    PubMed

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

    2016-03-01

    Hormones, particularly thyroid hormones and corticosteroids, play critical roles in vertebrate life stage transitions such as amphibian metamorphosis, hatching in precocial birds, and smoltification in salmonids. Since they synergistically regulate several metabolic and developmental processes that accompany vertebrate life stage transitions, the existence of extensive cross-communication between the adrenal/interrenal and thyroidal axes is not surprising. Synergies of corticosteroids and thyroid hormones are based on effects at the level of tissue hormone sensitivity and gene regulation. In addition, in representative nonmammalian vertebrates, corticotropin-releasing hormone (CRH) stimulates hypophyseal thyrotropin secretion, and thus functions as a common regulator of both the adrenal/interrenal and thyroidal axes to release corticosteroids and thyroid hormones. The dual function of CRH has been speculated to control or affect the timing of vertebrate life history transitions across taxa. After a brief overview of recent insights in the molecular mechanisms behind the synergic actions of thyroid hormones and corticosteroids during life stage transitions, this review examines the evidence for a possible role of CRH in controlling vertebrate life stage transitions. PMID:26874222

  1. Vertebral Artery Hypoplasia in a Black Kenyan Population

    PubMed Central

    Ogeng'o, Julius; Olabu, Beda; Sinkeet, Rankeet; Ogeng'o, Nafula M.; Elbusaid, Hemedi

    2014-01-01

    This study examined the characteristics of vertebral artery hypoplasia in 346 arteries of adult black Kenyans. The circumference was measured on haematoxylin/eosin stained microscopic sections of the distal one-third of the intracranial vertebral arteries using scion image analyser. Internal diameter was calculated in millimetre. Data were analysed using SPSS version 16.0. Vertebral artery hypoplasia (diameter < 2.0 mm) occurred in 100 (28.9%) arteries. Sixty of these (17.3%) were on the left and 40 (11.6%) on the right. Sixty (17.3%) were in females while 40 (11.6%) were in males. The side and gender differences were statistically significant at confidence interval of 95%. Frequency of vertebral artery hypoplasia was higher than in most other populations studied. The condition differs from that in other populations because it is more common on the left side and in females. We recommend ultrasound, angio-CT, or angio-MRI evaluation of vertebral arterial system before diagnostic or interventional procedures on posterior circulation.

  2. The amphioxus genome illuminates vertebrate origins and cephalochordate biology

    PubMed Central

    Holland, Linda Z.; Albalat, Ricard; Azumi, Kaoru; Benito-Gutiérrez, Èlia; Blow, Matthew J.; Bronner-Fraser, Marianne; Brunet, Frederic; Butts, Thomas; Candiani, Simona; Dishaw, Larry J.; Ferrier, David E.K.; Garcia-Fernàndez, Jordi; Gibson-Brown, Jeremy J.; Gissi, Carmela; Godzik, Adam; Hallböök, Finn; Hirose, Dan; Hosomichi, Kazuyoshi; Ikuta, Tetsuro; Inoko, Hidetoshi; Kasahara, Masanori; Kasamatsu, Jun; Kawashima, Takeshi; Kimura, Ayuko; Kobayashi, Masaaki; Kozmik, Zbynek; Kubokawa, Kaoru; Laudet, Vincent; Litman, Gary W.; McHardy, Alice C.; Meulemans, Daniel; Nonaka, Masaru; Olinski, Robert P.; Pancer, Zeev; Pennacchio, Len A.; Pestarino, Mario; Rast, Jonathan P.; Rigoutsos, Isidore; Robinson-Rechavi, Marc; Roch, Graeme; Saiga, Hidetoshi; Sasakura, Yasunori; Satake, Masanobu; Satou, Yutaka; Schubert, Michael; Sherwood, Nancy; Shiina, Takashi; Takatori, Naohito; Tello, Javier; Vopalensky, Pavel; Wada, Shuichi; Xu, Anlong; Ye, Yuzhen; Yoshida, Keita; Yoshizaki, Fumiko; Yu, Jr-Kai; Zhang, Qing; Zmasek, Christian M.; de Jong, Pieter J.; Osoegawa, Kazutoyo; Putnam, Nicholas H.; Rokhsar, Daniel S.; Satoh, Noriyuki; Holland, Peter W.H.

    2008-01-01

    Cephalochordates, urochordates, and vertebrates evolved from a common ancestor over 520 million years ago. To improve our understanding of chordate evolution and the origin of vertebrates, we intensively searched for particular genes, gene families, and conserved noncoding elements in the sequenced genome of the cephalochordate Branchiostoma floridae, commonly called amphioxus or lancelets. Special attention was given to homeobox genes, opsin genes, genes involved in neural crest development, nuclear receptor genes, genes encoding components of the endocrine and immune systems, and conserved cis-regulatory enhancers. The amphioxus genome contains a basic set of chordate genes involved in development and cell signaling, including a fifteenth Hox gene. This set includes many genes that were co-opted in vertebrates for new roles in neural crest development and adaptive immunity. However, where amphioxus has a single gene, vertebrates often have two, three, or four paralogs derived from two whole-genome duplication events. In addition, several transcriptional enhancers are conserved between amphioxus and vertebrates—a very wide phylogenetic distance. In contrast, urochordate genomes have lost many genes, including a diversity of homeobox families and genes involved in steroid hormone function. The amphioxus genome also exhibits derived features, including duplications of opsins and genes proposed to function in innate immunity and endocrine systems. Our results indicate that the amphioxus genome is elemental to an understanding of the biology and evolution of nonchordate deuterostomes, invertebrate chordates, and vertebrates. PMID:18562680

  3. Cement Leakage into Adjacent Vertebral Body Following Percutaneous Vertebroplasty

    PubMed Central

    Park, Jae Hoo; Kim, Hyeun Sung

    2016-01-01

    Percutaneous vertebroplasty (PV) is a minimally invasive procedure for osteoporotic vertebral compression fractures that fail to respond to conventional conservative treatment. It significantly improves intolerable back pain within hours, and has a low complication rate. Although rare, PV is not free of complications, most of which are directly related to cement leakage. Because of its association with new adjacent fracture, the importance of cement leakage into the adjacent disc space is paramount. Here, we report an interesting case of cement leakage into the adjacent upper vertebral body as well as disc space following PV. To the best of our knowledge, there has been no report of cement leakage into the adjacent vertebral body following PV. This rare case is presented along with a review of the literature. PMID:27437018

  4. Translational control of tropomyosin expression in vertebrate hearts.

    PubMed

    Dube, Dipak K; McLean, Matthew D; Dube, Syamalima; Poiesz, Bernard J

    2014-09-01

    The tropomyosin (TM) gene family produces a set of related TM proteins with important functions in striated and smooth muscle, and nonmuscle cells. In vertebrate striated muscle, the thin filament consists largely of actin, TM, the troponin (Tn) complex (Tn-I, Tn-C and Tn-T), and tropomodulin (Tmod) and is responsible for mediating Ca(2+) control of muscle contraction and relaxation. There are four known genes (designated as TPM1, TPM2, TPM3, and TPM4) for TM in vertebrates. The four TM genes generate a multitude of tissue- and developmental-specific isoforms through the use of different promoters, alternative mRNA splicing, different 3'-end mRNA processing and tissue-specific translational control. In this review, we have focused mainly on the regulation of TM expression in striated muscles, primarily in vertebrate hearts with special emphasis on translational control using mouse and Mexican axolotl animal models. PMID:25125172

  5. Conserved and Divergent Patterns of DNA Methylation in Higher Vertebrates

    PubMed Central

    Jiang, Ning; Wang, Lin; Chen, Jing; Wang, Luwen; Leach, Lindsey; Luo, Zewei

    2014-01-01

    DNA methylation in the genome plays a fundamental role in the regulation of gene expression and is widespread in the genome of eukaryotic species. For example, in higher vertebrates, there is a “global” methylation pattern involving complete methylation of CpG sites genome-wide, except in promoter regions that are typically enriched for CpG dinucleotides, or so called “CpG islands.” Here, we comprehensively examined and compared the distribution of CpG sites within ten model eukaryotic species and linked the observed patterns to the role of DNA methylation in controlling gene transcription. The analysis revealed two distinct but conserved methylation patterns for gene promoters in human and mouse genomes, involving genes with distinct distributions of promoter CpGs and gene expression patterns. Comparative analysis with four other higher vertebrates revealed that the primary regulatory role of the DNA methylation system is highly conserved in higher vertebrates. PMID:25355807

  6. The largest Silurian vertebrate and its palaeoecological implications

    PubMed Central

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

    2014-01-01

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

  7. A comparative view of regenerative neurogenesis in vertebrates.

    PubMed

    Alunni, Alessandro; Bally-Cuif, Laure

    2016-03-01

    In all vertebrate species studied thus far, the adult central nervous system harbors neural stem cells that sustain constitutive neurogenesis, as well as latent neural progenitors that can be awakened in lesional contexts. In spite of this common theme, many species differ dramatically in their ability to recruit constitutive progenitors, to awaken latent progenitors, or to enhance or bias neural progenitor fate to achieve successful neuronal repair. This Review summarizes the striking similarities in the essential molecular and cellular properties of adult neural stem cells between different vertebrate species, both under physiological and reparative conditions. It also emphasizes the differences in the reparative process across evolution and how the study of non-mammalian models can provide insights into both basic neural stem cell properties and stimulatory cues shared between vertebrates, and subsequent neurogenic events, which are abortive under reparative conditions in mammals. PMID:26932669

  8. Evolution of lung breathing from a lungless primitive vertebrate.

    PubMed

    Hoffman, M; Taylor, B E; Harris, M B

    2016-04-01

    Air breathing was critical to the terrestrial radiation and evolution of tetrapods and arose in fish. The vertebrate lung originated from a progenitor structure present in primitive boney fish. The origin of the neural substrates, which are sensitive to metabolically produced CO2 and which rhythmically activate respiratory muscles to match lung ventilation to metabolic demand, is enigmatic. We have found that a distinct periodic centrally generated rhythm, described as "cough" and occurring in lamprey in vivo and in vitro, is modulated by central sensitivity to CO2. This suggests that elements critical for the evolution of breathing in tetrapods, were present in the most basal vertebrate ancestors prior to the evolution of the lung. We propose that the evolution of breathing in all vertebrates occurred through exaptations derived from these critical basal elements. PMID:26476056

  9. Heparan sulfate proteoglycans: a sugar code for vertebrate development?

    PubMed

    Poulain, Fabienne E; Yost, H Joseph

    2015-10-15

    Heparan sulfate proteoglycans (HSPGs) have long been implicated in a wide range of cell-cell signaling and cell-matrix interactions, both in vitro and in vivo in invertebrate models. Although many of the genes that encode HSPG core proteins and the biosynthetic enzymes that generate and modify HSPG sugar chains have not yet been analyzed by genetics in vertebrates, recent studies have shown that HSPGs do indeed mediate a wide range of functions in early vertebrate development, for example during left-right patterning and in cardiovascular and neural development. Here, we provide a comprehensive overview of the various roles of HSPGs in these systems and explore the concept of an instructive heparan sulfate sugar code for modulating vertebrate development. PMID:26487777

  10. The evolution and development of vertebrate lateral line electroreceptors

    PubMed Central

    Baker, Clare V. H.; Modrell, Melinda S.; Gillis, J. Andrew

    2016-01-01

    Summary Electroreception is an ancient vertebrate sense with a fascinating evolutionary history involving multiple losses as well as independent evolution at least twice within teleosts. We review the phylogenetic distribution of electroreception and the morphology and innervation of electroreceptors in different vertebrate groups. We summarise recent work from our laboratory that has confirmed the homology of ampullary electroreceptors in non-teleost jawed vertebrates by showing, in conjunction with previously published work, that these are derived embryonically from lateral line placodes. Finally, we review hypotheses to explain the distribution of electroreception within teleosts, including the hypothesis that teleost ampullary and tuberous electroreceptors evolved via the modification of mechanosensory hair cells in lateral line neuromasts. We conclude that further experimental work on teleost electroreceptor development is needed to test such hypotheses. PMID:23761476

  11. Early Chordate Origins of the Vertebrate Second Heart Field

    PubMed Central

    Stolfi, Alberto; Gainous, T. Blair; Young, John J.; Mori, Alessandro; Levine, Michael; Christiaen, Lionel

    2016-01-01

    The vertebrate heart is formed from diverse embryonic territories, including the first and second heart fields. The second heart field (SHF) gives rise to the right ventricle and outflow tract, yet its evolutionary origins are unclear. We found that heart progenitor cells of the simple chordate Ciona intestinalis also generate precursors of the atrial siphon muscles (ASMs). These precursors express Islet and Tbx1/10, evocative of the splanchnic mesoderm that produces the lower jaw muscles and SHF of vertebrates. Evidence is presented that the transcription factor COE is a critical determinant of ASM fate. We propose that the last common ancestor of tunicates and vertebrates possessed multipotent cardiopharyngeal muscle precursors, and that their reallocation might have contributed to the emergence of the SHF. PMID:20671188

  12. A comparative view of regenerative neurogenesis in vertebrates

    PubMed Central

    Alunni, Alessandro; Bally-Cuif, Laure

    2016-01-01

    In all vertebrate species studied thus far, the adult central nervous system harbors neural stem cells that sustain constitutive neurogenesis, as well as latent neural progenitors that can be awakened in lesional contexts. In spite of this common theme, many species differ dramatically in their ability to recruit constitutive progenitors, to awaken latent progenitors, or to enhance or bias neural progenitor fate to achieve successful neuronal repair. This Review summarizes the striking similarities in the essential molecular and cellular properties of adult neural stem cells between different vertebrate species, both under physiological and reparative conditions. It also emphasizes the differences in the reparative process across evolution and how the study of non-mammalian models can provide insights into both basic neural stem cell properties and stimulatory cues shared between vertebrates, and subsequent neurogenic events, which are abortive under reparative conditions in mammals. PMID:26932669

  13. Evolutionary perspectives on clonal reproduction in vertebrate animals

    PubMed Central

    Avise, John C.

    2015-01-01

    A synopsis is provided of different expressions of whole-animal vertebrate clonality (asexual organismal-level reproduction), both in the laboratory and in nature. For vertebrate taxa, such clonal phenomena include the following: human-mediated cloning via artificial nuclear transfer; intergenerational clonality in nature via parthenogenesis and gynogenesis; intergenerational hemiclonality via hybridogenesis and kleptogenesis; intragenerational clonality via polyembryony; and what in effect qualifies as clonal replication via self-fertilization and intense inbreeding by simultaneous hermaphrodites. Each of these clonal or quasi-clonal mechanisms is described, and its evolutionary genetic ramifications are addressed. By affording an atypical vantage on standard vertebrate reproduction, clonality offers fresh perspectives on the evolutionary and ecological significance of recombination-derived genetic variety. PMID:26195735

  14. Vertebrate palaeontology of Australasia into the twenty-first century

    PubMed Central

    Nguyen, Jacqueline M. T.; Molak, Martyna; Black, Karen H.; Fitzgerald, Erich M. G.; Travouillon, Kenny J.; Ho, Simon Y. W.

    2011-01-01

    The 13th Conference on Australasian Vertebrate Evolution Palaeontology and Systematics (CAVEPS) took place in Perth, Western Australia, from 27 to 30 April 2011. This biennial meeting was jointly hosted by Curtin University, the Western Australian Museum, Murdoch University and the University of Western Australia. Researchers from diverse disciplines addressed many aspects of vertebrate evolution, including functional morphology, phylogeny, ecology and extinctions. New additions to the fossil record were reported, especially from hitherto under-represented ages and clades. Yet, application of new techniques in palaeobiological analyses dominated, such as dental microwear and geochronology, and technological advances, including computed tomography and ancient biomolecules. This signals a shift towards increased emphasis in interpreting broader evolutionary patterns and processes. Nonetheless, further field exploration for new fossils and systematic descriptions will continue to shape our understanding of vertebrate evolution in this little-studied, but most unusual, part of the globe. PMID:21715395

  15. 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. PMID:26928226

  16. Identification of chemosensory receptor genes from vertebrate genomes.

    PubMed

    Niimura, Yoshihito

    2013-01-01

    Chemical senses are essential for the survival of animals. In vertebrates, mainly three different types of receptors, olfactory receptors (ORs), vomeronasal receptors type 1 (V1Rs), and vomeronasal receptors type 2 (V2Rs), are responsible for the detection of chemicals in the environment. Mouse or rat genomes contain >1,000 OR genes, forming the largest multigene family in vertebrates, and have >100 V1R and V2R genes as well. Recent advancement in genome sequencing enabled us to computationally identify nearly complete repertories of OR, V1R, and V2R genes from various organisms, revealing that the numbers of these genes are highly variable among different organisms depending on each species' living environment. Here I would explain bioinformatic methods to identify the entire repertoires of OR, V1R, and V2R genes from vertebrate genome sequences. PMID:24014356

  17. GONAD MORPHOGENESIS IN VERTEBRATES: DIVERGENT MEANS TO A CONVERGENT END

    PubMed Central

    DeFalco, Tony; Capel, Blanche

    2015-01-01

    A critical element of successful sexual reproduction is the generation of sexually dimorphic adult reproductive organs, the testis and ovary, which produce functional gametes. The examination of different vertebrate species shows that the adult gonad is remarkably similar in its morphology across different phylogenetic classes. Surprisingly, however, the cellular and molecular programs employed to create similar organs are not evolutionarily conserved. We highlight the mechanisms used by different vertebrate model systems to generate the somatic architecture necessary to support gametogenesis. In addition, we examine the different vertebrate patterns of germ cell migration from their site of origin to colonize the gonad, and highlight their roles in sex-specific morphogenesis. We also discuss the plasticity of the adult gonad and consider how different genetic and environmental conditions can induce transitions between testis and ovary morphology. PMID:19807280

  18. Identification of a Novel Gig2 Gene Family Specific to Non-Amniote Vertebrates

    PubMed Central

    Zhang, Yi-Bing; Liu, Ting-Kai; Jiang, Jun; Shi, Jun; Liu, Ying; Li, Shun; Gui, Jian-Fang

    2013-01-01

    Gig2 (grass carp reovirus (GCRV)-induced gene 2) is first identified as a novel fish interferon (IFN)-stimulated gene (ISG). Overexpression of a zebrafish Gig2 gene can protect cultured fish cells from virus infection. In the present study, we identify a novel gene family that is comprised of genes homologous to the previously characterized Gig2. EST/GSS search and in silico cloning identify 190 Gig2 homologous genes in 51 vertebrate species ranged from lampreys to amphibians. Further large-scale search of vertebrate and invertebrate genome databases indicate that Gig2 gene family is specific to non-amniotes including lampreys, sharks/rays, ray-finned fishes and amphibians. Phylogenetic analysis and synteny analysis reveal lineage-specific expansion of Gig2 gene family and also provide valuable evidence for the fish-specific genome duplication (FSGD) hypothesis. Although Gig2 family proteins exhibit no significant sequence similarity to any known proteins, a typical Gig2 protein appears to consist of two conserved parts: an N-terminus that bears very low homology to the catalytic domains of poly(ADP-ribose) polymerases (PARPs), and a novel C-terminal domain that is unique to this gene family. Expression profiling of zebrafish Gig2 family genes shows that some duplicate pairs have diverged in function via acquisition of novel spatial and/or temporal expression under stresses. The specificity of this gene family to non-amniotes might contribute to a large extent to distinct physiology in non-amniote vertebrates. PMID:23593256

  19. Do global diversity patterns of vertebrates reflect those of monocots?

    PubMed

    McInnes, Lynsey; Jones, F Andrew; Orme, C David L; Sobkowiak, Benjamin; Barraclough, Timothy G; Chase, Mark W; Govaerts, Rafaël; Soltis, Douglas E; Soltis, Pamela S; Savolainen, Vincent

    2013-01-01

    Few studies of global diversity gradients in plants exist, largely because the data are not available for all species involved. Instead, most global studies have focussed on vertebrates, as these taxa have historically been associated with the most complete data. Here, we address this shortfall by first investigating global diversity gradients in monocots, a morphologically and functionally diverse clade representing a quarter of flowering plant diversity, and then assessing congruence between monocot and vertebrate diversity patterns. To do this, we create a new dataset that merges biome-level associations for all monocot genera with country-level associations for almost all ∼70,000 species. We then assess the evidence for direct versus indirect effects of this plant diversity on vertebrate diversity using a combination of linear regression and structural equation modelling (SEM). Finally, we also calculate overlap of diversity hotspots for monocots and each vertebrate taxon. Monocots follow a latitudinal gradient although with pockets of extra-tropical diversity, mirroring patterns in vertebrates. Monocot diversity is positively associated with vertebrate diversity, but the strength of correlation varies depending on the clades being compared. Monocot diversity explains marginal amounts of variance (<10%) after environmental factors have been accounted for. However, correlations remain among model residuals, and SEMs apparently reveal some direct effects of monocot richness. Our results suggest that collinear responses to environmental gradients are behind much of the congruence observed, but that there is some evidence for direct effects of producer diversity on consumer diversity. Much remains to be done before broad-scale diversity gradients among taxa are fully explained. Our dataset of monocot distributions will aid in this endeavour. PMID:23658679

  20. Prevalent Morphometric Vertebral Fractures in Professional Male Rugby Players

    PubMed Central

    Hind, Karen; Birrell, Fraser; Beck, Belinda

    2014-01-01

    There is an ongoing concern about the risk of injury to the spine in professional rugby players. The objective of this study was to investigate the prevalence of vertebral fracture using vertebral fracture assessment (VFA) dual energy X-ray absorptiometry (DXA) imaging in professional male rugby players. Ninety five professional rugby league (n = 52) and union (n = 43) players (n = 95; age 25.9 (SD 4.3) years; BMI: 29.5 (SD 2.9) kg.m2) participated in the research. Each participant received one VFA, and one total body and lumbar spine DXA scan (GE Lunar iDXA). One hundred and twenty vertebral fractures were identified in over half of the sample by VFA. Seventy four were graded mild (grade 1), 40 moderate (grade 2) and 6 severe (grade 3). Multiple vertebral fractures (≥2) were found in 37 players (39%). There were no differences in prevalence between codes, or between forwards and backs (both 1.2 v 1.4; p>0.05). The most common sites of fracture were T8 (n = 23), T9 (n = 18) and T10 (n = 21). The mean (SD) lumbar spine bone mineral density Z-score was 2.7 (1.3) indicating high player bone mass in comparison with age- and sex-matched norms. We observed a high number of vertebral fractures using DXA VFA in professional rugby players of both codes. The incidence, aetiology and consequences of vertebral fractures in professional rugby players are unclear, and warrant timely, prospective investigation. PMID:24846310

  1. Nucleic Acid Templated Chemical Reaction in a Live Vertebrate

    PubMed Central

    2016-01-01

    Nucleic acid templated reactions are enabled by the hybridization of probe-reagent conjugates resulting in high effective reagent concentration and fast chemical transformation. We have developed a reaction that harnesses cellular microRNA (miRNA) to yield the cleavage of a linker releasing fluorogenic rhodamine in a live vertebrate. The reaction is based on the catalytic photoreduction of an azide by a ruthenium complex. We showed that this system reports specific expression of miRNA in living tissues of a vertebrate. PMID:27413783

  2. How can mathematics help us explore vertebrate segmentation?

    PubMed Central

    Baker, Ruth E.; Schnell, Santiago

    2009-01-01

    Since the discovery of gene products oscillating during the formation of vertebral segments, much attention has been directed toward eluciating the molecular basis of the so-called segmentation clock. What research has told us is, that even in the most simple vertebrates, enormously complicated gene networks act in each cell to give rise to oscillations, and that cell-cell communication synchronizes these oscillations between neighboring cells. A number of theories have been proposed to explain both the initiation and maintenance of oscillations in a single cell and the synchronization of such oscillations between cells. We discuss these theories in this Commentary. PMID:19649154

  3. Shark-bitten vertebrate coprolites from the Miocene of Maryland

    NASA Astrophysics Data System (ADS)

    Godfrey, Stephen J.; Smith, Joshua B.

    2010-05-01

    Coprolites (fossilized feces) preserve a wide range of biogenic components, from bacteria and spores to a variety of vertebrate tissues. Two coprolites from the Calvert Cliffs outcrop belt (Miocene-aged Chesapeake Group), MD, USA, preserve shark tooth impressions in the form of partial dental arcades. The specimens are the first known coprolites to preserve vertebrate tooth marks. They provide another example of trace fossils providing evidence of prehistoric animal behaviors that cannot be directly approached through the study of body fossils. Shark behaviors that could account for these impressions include: (1) aborted coprophagy, (2) benthic or nektonic exploration, or (3) predation.

  4. Shark-bitten vertebrate coprolites from the Miocene of Maryland.

    PubMed

    Godfrey, Stephen J; Smith, Joshua B

    2010-05-01

    Coprolites (fossilized feces) preserve a wide range of biogenic components, from bacteria and spores to a variety of vertebrate tissues. Two coprolites from the Calvert Cliffs outcrop belt (Miocene-aged Chesapeake Group), MD, USA, preserve shark tooth impressions in the form of partial dental arcades. The specimens are the first known coprolites to preserve vertebrate tooth marks. They provide another example of trace fossils providing evidence of prehistoric animal behaviors that cannot be directly approached through the study of body fossils. Shark behaviors that could account for these impressions include: (1) aborted coprophagy, (2) benthic or nektonic exploration, or (3) predation. PMID:20213300

  5. Increase in vertebral body size in postmenopausal women with osteoporosis.

    PubMed

    Briot, K; Kolta, S; Fechtenbaum, J; Said-Nahal, R; Benhamou, C L; Roux, C

    2010-08-01

    Bone geometry plays a prominent role in bone strength. Cross-sectional studies have shown that advancing age is associated with increasing diameter of long bones, related to both periostal apposition and endosteal resorption. However, there are few data provided by prospective studies, especially concerning the changes in vertebral body dimensions. The objective of this prospective study was to measure the changes occurring in the vertebral body size of women with postmenopausal osteoporosis. Three-year data from placebo groups of the SOTI and TROPOS trials, performed in women with postmenopausal osteoporosis, were used for this study. In these trials, patients underwent lateral radiographs of the thoracic and lumbar spine at baseline and annually over 3 years, according to standardized procedures. Six-point digitization method was used: the four corner points of the vertebral body from T4 to L4 are marked, as well as an additional point in the middle of the upper and lower endplates. From these 6 points, the vertebral body perimeter, area and depth were measured at baseline and at 3 years. The analysis excluded all vertebrae with prevalent or incident fracture. A total of 2017 postmenopausal women (mean age 73.4+/-6.1 years) with a mean lumbar spine T score of -3.1+/-1.5, and a mean femoral neck T score of -3.0+/-0.7 are included in the analysis. Vertebral body dimensions increased over 3 years, by 2.1+/-5.5% (mean depth+/-SD), by 1.7+/-8.3% (mean area+/-SD) and by 1.5+/-4.9% (mean perimeter+/-SD) at the thoracic level (T4 to T12). At the lumbar level (L1 to L4), these dimensions increased as well: 1.4+/-3.6% (mean depth+/-SD), 1.4+/-5.7% (mean area+/-SD), 0.7+/-2.9% (mean perimeter+/-SD). A significant increase in vertebral body size was observed for each vertebral level from T5 to L4 for each of these parameters (p<0.01). These prospective results demonstrate that vertebral body dimensions increase over 3 years in women with postmenopausal osteoporosis. PMID

  6. Transient Cortical Blindness Following Vertebral Angiography: A Case Report

    PubMed Central

    Chan, Ho Fung; Ma, Ka Fai; Cheng, Lik Fai; Chan, Tony KT

    2015-01-01

    Transient cortical blindness (TCB) is a rare but well-known complication of cerebral angiography. Its pathophysiology remains uncertain. We would like to report a case of TCB in a patient during a follow up vertebral angiogram for post-coil embolization of left posterior inferior cerebellar artery aneurysm. Patient's vision was resumed spontaneously within 24 hours after angiography, with no residual neurological deficit in subsequent clinical follow up. Multi-modality imaging evaluation including vertebral angiography, brain CT and MRI performed on same day are presented. PMID:25763297

  7. Molecular genetics and the evolution of ultraviolet vision in vertebrates

    PubMed Central

    Shi, Yongsheng; Radlwimmer, F. Bernhard; Yokoyama, Shozo

    2001-01-01

    Despite the biological importance of UV vision, its molecular bases are not well understood. Here, we present evidence that UV vision in vertebrates is determined by eight specific amino acids in the UV pigments. Amino acid sequence analyses show that contemporary UV pigments inherited their UV sensitivities from the vertebrate ancestor by retaining most of these eight amino acids. In the avian lineage, the ancestral pigment lost UV sensitivity, but some descendants regained it by one amino acid change. Our results also strongly support the hypothesis that UV pigments have an unprotonated Schiff base-linked chromophore. PMID:11573008

  8. Changes in the adult vertebrate auditory sensory epithelium after trauma.

    PubMed

    Oesterle, Elizabeth C

    2013-03-01

    Auditory hair cells transduce sound vibrations into membrane potential changes, ultimately leading to changes in neuronal firing and sound perception. This review provides an overview of the characteristics and repair capabilities of traumatized auditory sensory epithelium in the adult vertebrate ear. Injured mammalian auditory epithelium repairs itself by forming permanent scars but is unable to regenerate replacement hair cells. In contrast, injured non-mammalian vertebrate ear generates replacement hair cells to restore hearing functions. Non-sensory support cells within the auditory epithelium play key roles in the repair processes. PMID:23178236

  9. Age of sex-determining mechanisms in vertebrates.

    PubMed

    WITSCHI, E

    1959-08-14

    Certain characteristic patterns of physiologic sex determination are not causally linked with types of genic and chromosomal constitution (XX-XY or ZW-ZZ). The observed widespread but not universal parallelism in the distribution of genetic and physiologic patterns among vertebrate groups expresses genealogic relationship. On the basis of this interpretation one may estimate the approximate evolutionary age of the mechanism of genetic sex determination. It is concluded that in all tetrapod vertebrates these mechanisms originated during the Jurassic period. Environmental conditions seem to affect the progress of this evolution. PMID:13675759

  10. Continuum theory of gene expression waves during vertebrate segmentation

    NASA Astrophysics Data System (ADS)

    Jörg, David J.; Morelli, Luis G.; Soroldoni, Daniele; Oates, Andrew C.; Jülicher, Frank

    2015-09-01

    The segmentation of the vertebrate body plan during embryonic development is a rhythmic and sequential process governed by genetic oscillations. These genetic oscillations give rise to traveling waves of gene expression in the segmenting tissue. Here we present a minimal continuum theory of vertebrate segmentation that captures the key principles governing the dynamic patterns of gene expression including the effects of shortening of the oscillating tissue. We show that our theory can quantitatively account for the key features of segmentation observed in zebrafish, in particular the shape of the wave patterns, the period of segmentation and the segment length as a function of time.

  11. The clinical effect of percutaneous kyphoplasty for the treatment of multiple osteoporotic vertebral compression fractures and the prevention of new vertebral fractures

    PubMed Central

    Zhai, Weifeng; Jia, Yongwei; Wang, Jianjie; Cheng, Liming; Zeng, Zhili; Yu, Yan; Chen, Lei

    2015-01-01

    This study aimed to investigate the clinical effect of percutaneous kyphoplasty and the precautions against adjacent vertebral refractures in the treatment of multiple osteoporotic vertebral compression fractures. 54 cases (128 vertebrae) with multiple osteoporotic vertebral compression fractures from July 2007 to December 2013 treated with percutaneous kyphoplasty were retrospectively reviewed. 36 cases of them suffered from bi-segment vertebral fractures, 16 cases with tri-segment vertebral fractures and 2 cases with quadri-segment vertebral fractures. The operative effect was evaluated by visual analogue scale (VAS) score and oswestry disability index (ODI) score. Then the reasons for adjacent vertebral refractures were analyzed and the precautions were proposed. 54 cases (128 vertebrae) were admitted with percutaneous kyphoplasty successfully. No pulmonary embolism, spinal cord injury and other serious complications were found. The follow-up took 3-33 months with the average of 12 months. There was significant difference of VAS scores and ODI scores between pre-operation and post-operation (P<0.05). Bone cement leakage occurred in 23 vertebrae, and the incidence rate was 18.0%. 8 cases sustained adjacent vertebral refractures including 3 cases in the contiguous vertebral bodies and 5 cases in the interval vertebral bodies, and the incidence rate was 14.8%. 5 cases gained fracture healing after additional percutaneous kyphoplasty procedures while the other 3 cases were healed basically after conservative treatment for three months. In conclusion, percutaneous kyphoplasty is safe and effective to treat multiple osteoporotic vertebral compression fractures. However, the risk of new adjacent vertebral fractures in the multiple osteoporotic vertebral compression fractures is higher than that in the single osteoporotic vertebral compression fracture. Timely and proper treatment can reduce refractures. PMID:26550284

  12. The UNC-45 Myosin Chaperone: From Worms to Flies to Vertebrates

    PubMed Central

    Lee, Chi F.; Melkani, Girish C.; Bernstein, Sanford I.

    2014-01-01

    UNC-45 is a UCS domain protein that is critical for myosin stability and function. It likely aides in folding myosin during cellular differentiation and maintenance and protects myosin from denaturation during stress. Invertebrates have a single unc-45 gene that is expressed in both muscle and non-muscle tissues. Vertebrates possess one gene expressed in striated muscle (unc-45b) and one that is more generally expressed (unc-45a). Structurally, UNC-45 is composed of a series of alpha-helices connected by loops. It has an N-terminal TPR domain that binds to Hsp90 and a central domain composed of armadillo repeats. Its C-terminal UCS domain, which is also comprised of helical armadillo repeats, interacts with myosin. In this review, we present biochemical, structural and genetic analyses of UNC-45 in Caenorhabditis elegans, Drosophila melanogaster and various vertebrates. Further, we provide insights into UNC-45 functions, its potential mechanism of action and its roles in human disease. PMID:25376491

  13. Maternal transfer of antibodies in vertebrates: trans-generational effects on offspring immunity

    PubMed Central

    Hasselquist, Dennis; Nilsson, Jan-Åke

    2008-01-01

    Maternal effects by which females provide their offspring with non-genetic factors such as hormones, nutrients and antibodies can have an important impact on offspring fitness. In vertebrates, maternal antibodies (matAb) are transferred from the mother, via the placenta, egg yolk or milk during lactation to offspring until they are 2 weeks (birds), 4–10 weeks (rodents) and 9 months (humans) old, respectively. matAb transfer can have direct effects on offspring growth rate in birds and rodents, probably by passively protecting the newborn from common pathogens before their endogenous immune system has matured. Indirect long-term effects of matAb transfer on the offspring's own immunity can be synergistic, if matAb act as antigen templates of the accumulated immunological experience of the mother and educate the newborn's immune system. However, it may also be suppressive if matAb reduce antigen presentation to the newborn resulting in antigen-specific blocking of offspring endogenous immunity. Our aim is to review the mechanisms and direct effects of matAb transfer in vertebrates with an emphasis on birds, outline a framework for research on the long-term effects of matAb on the endogenous immune system of the mature offspring and encourage ecological and evolutionary studies of matAb transfer in non-domesticated animals. PMID:18926976

  14. Emergence of the acute-phase protein hemopexin in jawed vertebrates

    PubMed Central

    Dooley, Helen; Buckingham, E. Bryan; Criscitiello, Michael F.; Flajnik, Martin F.

    2010-01-01

    When released from damaged erythrocytes free heme not only provides a source of iron for invading bacteria but is also highly toxic due to its ability to catalyze free radical formation. Hemopexin (Hx) binds free heme with very high affinity and thus protects against heme toxicity, sequesters heme from pathogens, and helps conserve valuable iron. Hx is also an acute-phase serum protein (APP), whose expression is induced by inflammation. To date Hx has been identified as far back in phylogeny as bony fish where it is called Warm-temperature Acclimation-related 65 kDa Protein (WAP65), as serum protein levels are increased at elevated environmental temperatures as well as by infection. During analysis of nurse shark (Ginglymostoma cirratum) plasma we isolated a Ni2+-binding serum glycoprotein and characterized it as the APP Hx. We subsequently cloned Hx from nurse shark and another cartilaginous fish species, the little skate Leucoraja erinacea. Functional analysis showed shark Hx, like that of mammals, binds heme but is found at unusually high levels in normal shark serum. As an Hx orthologue could not be found in the genomes of jawless vertebrates or lower deuterostomes it appears to have arisen just prior to the emergence of jawed vertebrates, coincident with the second round of genome wide duplication and the appearance of tetrameric haemoglobin (Hb). PMID:20884052

  15. Rate-dependent fracture characteristics of lumbar vertebral bodies.

    PubMed

    Stemper, Brian D; Yoganandan, Narayan; Baisden, Jamie L; Umale, Sagar; Shah, Alok S; Shender, Barry S; Paskoff, Glenn R

    2015-01-01

    Experimental testing incorporating lumbar columns and isolated components is essential to advance the understanding of injury tolerance and for the development of safety enhancements. This study incorporated a whole column axial acceleration model and an isolated vertebral body model to quantify compression rates during realistic loading and compressive tolerance of vertebrae. Eight lumbar columns and 53 vertebral bodies from 23 PMHS were used. Three-factor ANOVA was used to determine significant differences (p<0.05) in physiologic and failure biomechanics based on compression rate, spinal level, and gender. Results demonstrated a significant increase in ultimate force (i.e., fracture) from lower to higher compression rates. Ultimate stress also increased with compression rate. Displacement and strain to failure were consistent at both compression rates. Differences in ultimate mechanics between vertebral bodies obtained from males and females demonstrated non-significant trends, with female vertebral bodies having lower ultimate force that would be associated with decreased injury tolerance. This was likely a result of smaller vertebrae in that population. Combined with existing literature, results presented in this manuscript contribute to the understanding of lumbar spine tolerance during axial loading events that occur in both military and civilian environments with regard to effects of compression rate and gender. PMID:25154535

  16. The molecular evolution of the vertebrate behavioural repertoire.

    PubMed

    Grant, Seth G N

    2016-01-01

    How the sophisticated vertebrate behavioural repertoire evolved remains a major question in biology. The behavioural repertoire encompasses the set of individual behavioural components that an organism uses when adapting and responding to changes in its external world. Although unicellular organisms, invertebrates and vertebrates share simple reflex responses, the fundamental mechanisms that resulted in the complexity and sophistication that is characteristic of vertebrate behaviours have only recently been examined. A series of behavioural genetic experiments in mice and humans support a theory that posited the importance of synapse proteome expansion in generating complexity in the behavioural repertoire. Genome duplication events, approximately 550 Ma, produced expansion in the synapse proteome that resulted in increased complexity in synapse signalling mechanisms that regulate components of the behavioural repertoire. The experiments demonstrate the importance to behaviour of the gene duplication events, the diversification of paralogues and sequence constraint. They also confirm the significance of comparative proteomic and genomic studies that identified the molecular origins of synapses in unicellular eukaryotes and the vertebrate expansion in proteome complexity. These molecular mechanisms have general importance for understanding the repertoire of behaviours in different species and for human behavioural disorders arising from synapse gene mutations. PMID:26598730

  17. 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. PMID:26817767

  18. Vertebral hemangioma coincident with metastasis of colon adenocarcinoma.

    PubMed

    Zapałowicz, Krzysztof; Bierzyńska-Macyszyn, Grażyna; Stasiów, Bartłomiej; Krzan, Aleksandra; Wierzycka, Beata; Kopycka, Anna

    2016-03-01

    The authors report on colon cancer metastasis to the L-3 vertebra, which had been previously found to be involved by an asymptomatic hemangioma. A 61-year-old female patient was admitted after onset of lumbar axial pain and weakness of the right quadriceps muscle. Her medical history included colon cancer that had been diagnosed 3 years earlier and was treated via a right hemicolectomy followed by chemotherapy. Presurgical imaging revealed an asymptomatic hemangioma in the L-3 vertebral body. Computed tomography and MRI of the spine were performed after admission and revealed a hemangioma in the L-3 vertebral body as well as a soft-tissue mass protruding from the L-3 vertebral body to the spinal canal. Treatment consisted of vertebroplasty of the hemangioma, left L-3 hemilaminectomy, and removal of the pathological mass from the spinal canal and the L-3 vertebral body. Histopathological examination revealed the presence of colon cancer metastasis and a hemangioma in the same vertebra. PMID:26588498

  19. Trends in Children's Concepts of Vertebrate and Invertebrate.

    ERIC Educational Resources Information Center

    Braund, Martin

    1998-01-01

    Presents the results of a cross-age study of 7- to 15-year-old children on their thinking about vertebrate and invertebrate animals. Suggests experiences that could be included in the school science curriculum and argues for more classroom work relating structure with function in order to address students' conceptual difficulties. (Contains 18…

  20. Asymptomatic Lumbar Vertebral Erosion from Inferior Vena Cava Filter Perforation

    SciTech Connect

    Fang, Wayne Hieb, Robert A.; Olson, Eric; Carrera, Guillermo F.

    2007-06-15

    In 2002, a 24-year-old female trauma patient underwent prophylactic inferior vena cava filter placement. Recurrent bouts of renal stones prompted serial CT imaging in 2004. In this brief report, we describe erosion and ossification of the L3 vertebral body by a Greenfield filter strut.

  1. Facultative parthenogenesis in a critically endangered wild vertebrate.

    PubMed

    Fields, Andrew T; Feldheim, Kevin A; Poulakis, Gregg R; Chapman, Demian D

    2015-06-01

    Facultative parthenogenesis - the ability of sexually reproducing species to sometimes produce offspring asexually - is known from a wide range of ordinarily sexually reproducing vertebrates in captivity, including some birds, reptiles and sharks [1-3]. Despite this, free-living parthenogens have never been observed in any of these taxa in the wild, although two free-living snakes were recently discovered each gestating a single parthenogen - one copperhead (Agkistrodon contortrix) and one cottonmouth (Agkistrodon piscivorus) [1]. Vertebrate parthenogens are characterized as being of the homogametic sex (e.g., females in sharks, males in birds) and by having elevated homozygosity compared to their mother [1-3], which may reduce their viability [4]. Although it is unknown if either of the parthenogenetic snakes would have been carried to term or survived in the wild, facultative parthenogenesis might have adaptive significance [1]. If this is true, it is reasonable to hypothesize that parthenogenesis would be found most often at low population density, when females risk reproductive failure because finding mates is difficult [5]. Here, we document the first examples of viable parthenogens living in a normally sexually reproducing wild vertebrate, the smalltooth sawfish (Pristis pectinata). We also provide a simple approach to screen any microsatellite DNA database for parthenogens, which will enable hypothesis-driven research on the significance of vertebrate parthenogenesis in the wild. PMID:26035783

  2. Overview of Vertebrate Animal Models of Fungal Infection

    PubMed Central

    Hohl, Tobias M.

    2014-01-01

    Fungi represent emerging infectious threats to human populations worldwide. Mice and other laboratory animals have proved invaluable in modeling clinical syndromes associated with superficial and life-threatening invasive mycoses. This review outlines salient features of common vertebrate animal model systems to study fungal pathogenesis, host antifungal immune responses, and antifungal compounds. PMID:24709390

  3. [Revision surgery after implantation of a vertebral disc prosthesis].

    PubMed

    Hopf, C

    2008-04-01

    Assessment of the revisability of surgery after the endoprosthetic replacement of vertebral discs shows that the surgical approach depends on the time of revision surgery and the reason why it is carried out. Our experience is based on nine revision operations out of 152 cervical vertebra prostheses of the Bryan and Prodisc C types implanted from 2003 to 2007 and 312 endoprostheses of the Charité and Prodisc types implanted from 1999 to 2007. Our own results show differing approaches in perioperative or late postoperative revision operations. Operations to exchange implants were not possible, whereas a change of surgical procedure is the rule. The same access route can usually be selected in the cervical spine, but in the lumbar spine this can only be done perioperatively; if revision surgery is carried out at a later date, an alternative access route must be used. Using strict indications for the primary implant is the only way to prevent postoperative revision surgery that is due to an inaccurate primary assessment and not to the vertebral endoprosthesis (e.g. post-discotomy syndrome, facet joint arthropathy, rotation instability, vertebral slip). The next generation of vertebral disc endoprostheses must incorporate reduced load of the zygapophyseal joints and improved revisability. PMID:18340432

  4. Bilateral carotid and bilateral vertebral artery dissection following facial massage.

    PubMed

    Chakrapani, Andrea L; Zink, Walter; Zimmerman, Robert; Riina, Howard; Benitez, Ronald

    A 50-year-old woman underwent facial massage. After 13 days, she experienced left retro-orbital pain, ptosis, and miosis. Magnetic resonance imaging (MRI) showed stenotic dissection of bilateral cervical internal carotid and vertebral arteries. The intracranial vasculature was intact. She was treated conservatively with long-term oral anticoagulation and remains asymptomatic 18 months later. PMID:18388028

  5. The origin of the myelination program in vertebrates.

    PubMed

    Zalc, B; Goujet, D; Colman, D

    2008-06-24

    The myelin sheath was a transformative vertebrate acquisition, enabling great increases in impulse propagation velocity along axons. Not all vertebrates possess myelinated axons, however, and when myelin first appeared in the vertebrate lineage is an important open question. It has been suggested that the dual, apparently unrelated acquisitions of myelin and the hinged jaw were actually coupled in evolution [1,2]. If so, it would be expected that myelin was first acquired during the Devonian period by the oldest jawed fish, the placoderms [3]. Although myelin itself is not retained in the fossil record, within the skulls of fossilized Paleozoic vertebrate fish are exquisitely preserved imprints of cranial nerves and the foramina they traversed. Examination of these structures now suggests how the nerves functioned in vivo. In placoderms, the first hinge-jawed fish, oculomotor nerve diameters remained constant, but nerve lengths were ten times longer than in the jawless osteostraci. We infer that to accommodate this ten-fold increase in length, while maintaining a constant diameter, the oculomotor system in placoderms must have been myelinated to function as a rapidly conducting motor pathway. Placoderms were the first fish with hinged jaws and some can grow to formidable lengths, requiring a rapid conduction system, so it is highly likely that they were the first organisms with myelinated axons in the craniate lineage. PMID:18579089

  6. Testing the evolutionary conservation of vocal motoneurons in vertebrates.

    PubMed

    Albersheim-Carter, Jacob; Blubaum, Aleksandar; Ballagh, Irene H; Missaghi, Kianoush; Siuda, Edward R; McMurray, George; Bass, Andrew H; Dubuc, Réjean; Kelley, Darcy B; Schmidt, Marc F; Wilson, Richard J A; Gray, Paul A

    2016-04-01

    Medullary motoneurons drive vocalization in many vertebrate lineages including fish, amphibians, birds, and mammals. The developmental history of vocal motoneuron populations in each of these lineages remains largely unknown. The highly conserved transcription factor Paired-like Homeobox 2b (Phox2b) is presumed to be expressed in all vertebrate hindbrain branchial motoneurons, including laryngeal motoneurons essential for vocalization in humans. We used immunohistochemistry and in situ hybridization to examine Phox2b protein and mRNA expression in caudal hindbrain and rostral spinal cord motoneuron populations in seven species across five chordate classes. Phox2b was present in motoneurons dedicated to sound production in mice and frogs (bullfrog, African clawed frog), but not those in bird (zebra finch) or bony fish (midshipman, channel catfish). Overall, the pattern of caudal medullary motoneuron Phox2b expression was conserved across vertebrates and similar to expression in sea lamprey. These observations suggest that motoneurons dedicated to sound production in vertebrates are not derived from a single developmentally or evolutionarily conserved progenitor pool. PMID:26160673

  7. Shifted magnetic alignment in vertebrates: Evidence for neural lateralization?

    PubMed

    Malkemper, E Pascal; Painter, Michael S; Landler, Lukas

    2016-06-21

    A wealth of evidence provides support for magnetic alignment (MA) behavior in a variety of disparate species within the animal kingdom, in which an animal, or a group of animals, show a tendency to align the body axis in a consistent orientation relative to the geomagnetic field lines. Interestingly, among vertebrates, MA typically coincides with the north-south magnetic axis, however, the mean directional preferences of an individual or group of organisms is often rotated clockwise from the north-south axis. We hypothesize that this shift is not a coincidence, and future studies of this subtle, yet consistent phenomenon may help to reveal some properties of the underlying sensory or processing mechanisms, that, to date, are not well understood. Furthermore, characterizing the fine structure exhibited in MA behaviors may provide key insights to the biophysical substrates mediating magnetoreception in vertebrates. Therefore, in order to determine if a consistent shift is exhibited in taxonomically diverse vertebrates, we performed a meta-analysis on published MA datasets from 23 vertebrate species that exhibited an axial north-south preference. This analysis revealed a significant clockwise shift from the north-south magnetic axis. We summarize and discuss possible competing hypotheses regarding the proximate mechanisms underlying the clockwise shifted MA and conclude that the most likely cause of such a shift would be a lateralization in central processing of magnetic information. PMID:27059891

  8. Reservoir Competence of Vertebrate Hosts for Anaplasma phagocytophilum

    PubMed Central

    Hersh, Michelle H.; Tibbetts, Michael; McHenry, Diana J.; Duerr, Shannon; Brunner, Jesse; Killilea, Mary; LoGiudice, Kathleen; Schmidt, Kenneth A.; Ostfeld, Richard S.

    2012-01-01

    Fourteen vertebrate species (10 mammals and 4 birds) were assessed for their ability to transmit Anaplasma phagocytophilum, the bacterium that causes human granulocytic anaplasmosis, to uninfected feeding ixodid ticks. Small mammals were most likely to infect ticks but all species assessed were capable of transmitting the bacterium, in contrast to previous findings. PMID:23171835

  9. Structural aspects of the calcification process of lower vertebrate collagen.

    PubMed

    Bigi, A; Koch, M H; Panzavolta, S; Roveri, N; Rubini, K

    2000-01-01

    In order to investigate the structural relationship between inorganic phase and collagen fibrils in the calcified tissues of lower vertebrates we have carried out a wide and small angle X-ray diffraction investigation on carp scales and bone samples. The small angle patterns from decalcified bone and scales, as well as uncalcified tendon samples from carp are very similar to that of type I collagen from higher vertebrates. The D-axial period, 67 nm, is the same as that of higher vertebrate type I collagen, while the most significant difference is the relatively low intensity of the first order reflection, which is, however, the most intense. The relative intensity distributions of the meridional reflections recorded from fish bone and scales are in agreement with an electron density distribution according to a step function. The calculated step length is very close to the values previously reported for calcified tissues from higher vertebrates. The small angle reflections from calcified, as well as decalcified, scales display different directions of orientation, which could be in agreement with a plywood arrangement of collagen fibrils in successive sheets parallel to the plane of the scale. PMID:10826707

  10. Late Cretaceous terrestrial vertebrate fauna, North Slope, Alaska

    SciTech Connect

    Clemens, W.A.; Allison, C.W.

    1985-01-01

    Closely related terrestrial vertebrates in Cretaceous mid-latitude (30/sup 0/ to 50/sup 0/) faunas of North America and Asia as well as scattered occurrences of footprints and skin impressions suggested that in the Late Mesozoic the Alaskan North Slope supported a diverse fauna. In 1961 abundant skeletal elements of Cretaceous, Alaskan dinosaurs (hadrosaurids) were discovered by the late R.L. Liscomb. This material is being described by K.L. Davies. Additional fossils collected by E.M. Brouwers and her associates include skeletal elements of hadrosaurid and carnosaurian (.tyrannosaurid) dinosaurs and other vertebrates. The fossil locality on the North Slope is not at about 70/sup 0/N. In the Late Cretaceous the members of this fauna were subject to the daylight regime and environment at a paleolatitude closer to 80/sup 0/N. Current hypotheses attributing extinctions of dinosaurs and some other terrestrial vertebrates to impact of an extraterrestrial object cite periods of darkness, decreased temperature (possibly followed by extreme warming) and acid rain as the direct causes of their demise. Unless members of this North Slope fauna undertook long-distance migrations, their high latitude occurrence indicates groups of dinosaurs and other terrestrial vertebrates regularly tolerated months of darkness.

  11. Complex Vertebral Arteriovenous Fistula and Ruptured Aneurysm in Neurofibromatosis

    PubMed Central

    Roth, Tori C.; Manness, Wayne K; Hershey, Beverly L.; Yazdi, Joseph

    2000-01-01

    The objective and importance of this study was to describe the challenges encountered with treating a high-flow vertebral arteriovenous fistula (AVF) and ruptured aneurysm in a patient with life-threatening hemorrhage. A 36-year-old female with Neurofibromatosis type 1 (NF1) presented 2 weeks after uneventful cesarean section with a rapidly expanding pulsatile neck mass. Angiography demonstrated a complex left vertebral AVF and multiple associated vertebral artery aneurysms. Emergent endovascular coil embolization was performed using a retrograde and antegrade approach to occlude the fistulas and trap the ruptured aneurysm, successfully treating the acute hemorrhage. Subsequent definitive therapy was accomplished utilizing a combined neurointerventional and neurosurgical strategy of direct-puncture acrylic embolization and ligation of the vertebral artery. Recent advances in neurointerventional technology allow novel approaches in the primary and/or preoperative treatment of complex vascular lesions such as those seen in NF1. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5p40-b PMID:17171099

  12. The molecular evolution of the vertebrate behavioural repertoire

    PubMed Central

    2016-01-01

    How the sophisticated vertebrate behavioural repertoire evolved remains a major question in biology. The behavioural repertoire encompasses the set of individual behavioural components that an organism uses when adapting and responding to changes in its external world. Although unicellular organisms, invertebrates and vertebrates share simple reflex responses, the fundamental mechanisms that resulted in the complexity and sophistication that is characteristic of vertebrate behaviours have only recently been examined. A series of behavioural genetic experiments in mice and humans support a theory that posited the importance of synapse proteome expansion in generating complexity in the behavioural repertoire. Genome duplication events, approximately 550 Ma, produced expansion in the synapse proteome that resulted in increased complexity in synapse signalling mechanisms that regulate components of the behavioural repertoire. The experiments demonstrate the importance to behaviour of the gene duplication events, the diversification of paralogues and sequence constraint. They also confirm the significance of comparative proteomic and genomic studies that identified the molecular origins of synapses in unicellular eukaryotes and the vertebrate expansion in proteome complexity. These molecular mechanisms have general importance for understanding the repertoire of behaviours in different species and for human behavioural disorders arising from synapse gene mutations. PMID:26598730

  13. Evidence for Evolution from the Vertebrate Fossil Record.

    ERIC Educational Resources Information Center

    Gingerich, Philip D.

    1983-01-01

    Discusses three examples of evolutionary transition in the vertebrate fossil record, considering evolutionary transitions at the species level. Uses archaic squirrel-like Paleocine primates, the earliest primates of modern aspect, as examples. Also reviews new evidence on the origin of whales and their transition from land to sea. (JN)

  14. NATURE OF CUMULATIVE IMPACTS ON BIOTIC DIVERSITY OF WETLAND VERTEBRATES

    EPA Science Inventory

    There is no longer any doubt that cumulative impacts have important effects on wetland vertebrates. he interactions of species diversity and community structure produce a complex pattern in which environmental impacts can play a highly significant role. ariety of examples shows h...

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

    PubMed Central

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

    2013-01-01

    Summary 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. PMID:23431116

  16. Recommended nomenclature for the vertebrate alcohol dehydrogenase gene family.

    PubMed

    Duester, G; Farrés, J; Felder, M R; Holmes, R S; Höög, J O; Parés, X; Plapp, B V; Yin, S J; Jörnvall, H

    1999-08-01

    The alcohol dehydrogenase (ADH) gene family encodes enzymes that metabolize a wide variety of substrates, including ethanol, retinol, other aliphatic alcohols, hydroxysteroids, and lipid peroxidation products. Studies on 19 vertebrate animals have identified ADH orthologs across several species, and this has now led to questions of how best to name ADH proteins and genes. Seven distinct classes of vertebrate ADH encoded by non-orthologous genes have been defined based upon sequence homology as well as unique catalytic properties or gene expression patterns. Each class of vertebrate ADH shares <70% sequence identity with other classes of ADH in the same species. Classes may be further divided into multiple closely related isoenzymes sharing >80% sequence identity such as the case for class I ADH where humans have three class I ADH genes, horses have two, and mice have only one. Presented here is a nomenclature that uses the widely accepted vertebrate ADH class system as its basis. It follows the guidelines of human and mouse gene nomenclature committees, which recommend coordinating names across species boundaries and eliminating Roman numerals and Greek symbols. We recommend that enzyme subunits be referred to by the symbol "ADH" (alcohol dehydrogenase) followed by an Arabic number denoting the class; i.e. ADH1 for class I ADH. For genes we recommend the italicized root symbol "ADH" for human and "Adh" for mouse, followed by the appropriate Arabic number for the class; i.e. ADH1 or Adh1 for class I ADH genes. For organisms where multiple species-specific isoenzymes exist within a class, we recommend adding a capital letter after the Arabic number; i.e. ADH1A, ADH1B, and ADH1C for human alpha, beta, and gamma class I ADHs, respectively. This nomenclature will accommodate newly discovered members of the vertebrate ADH family, and will facilitate functional and evolutionary studies. PMID:10424757

  17. EGR1 and EGR2 involvement in vertebrate tendon differentiation.

    PubMed

    Lejard, Véronique; Blais, Frédéric; Guerquin, Marie-Justine; Bonnet, Aline; Bonnin, Marie-Ange; Havis, Emmanuelle; Malbouyres, Maryline; Bidaud, Christelle Bonod; Maro, Géraldine; Gilardi-Hebenstreit, Pascale; Rossert, Jérome; Ruggiero, Florence; Duprez, Delphine

    2011-02-18

    The molecules involved in vertebrate tendon formation during development remain largely unknown. To date, only two DNA-binding proteins have been identified as being involved in vertebrate tendon formation, the basic helix-loop-helix transcription factor Scleraxis and, recently, the Mohawk homeobox gene. We investigated the involvement of the early growth response transcription factors Egr1 and Egr2 in vertebrate tendon formation. We established that Egr1 and Egr2 expression in tendon cells was correlated with the increase of collagen expression during tendon cell differentiation in embryonic limbs. Vertebrate tendon differentiation relies on a muscle-derived FGF (fibroblast growth factor) signal. FGF4 was able to activate the expression of Egr genes and that of the tendon-associated collagens in chick limbs. Egr gene misexpression experiments using the chick model allowed us to establish that either Egr gene has the ability to induce de novo expression of the reference tendon marker scleraxis, the main tendon collagen Col1a1, and other tendon-associated collagens Col3a1, Col5a1, Col12a1, and Col14a1. Mouse mutants for Egr1 or Egr2 displayed reduced amounts of Col1a1 transcripts and a decrease in the number of collagen fibrils in embryonic tendons. Moreover, EGR1 and EGR2 trans-activated the mouse Col1a1 proximal promoter and were recruited to the tendon regulatory regions of this promoter. These results identify EGRs as novel DNA-binding proteins involved in vertebrate tendon differentiation by regulating type I collagen production. PMID:21173153

  18. Subfunctionalization and neofunctionalization of vertebrate Lef/Tcf transcription factors.

    PubMed

    Klingel, Susanne; Morath, Iris; Strietz, Juliane; Menzel, Katharina; Holstein, Thomas W; Gradl, Dietmar

    2012-08-01

    Invertebrates express a multitude of Wnt ligands and all Wnt/β-catenin signaling pathways converge to only one nuclear Lef/Tcf. In vertebrates, however, four distinct Lef/Tcfs, i.e. Tcf-1, Lef, Tcf-3, and Tcf-4 fulfill this function. At present, it is largely unknown to what extent the various Lef/Tcfs are functionally similar or diversified in vertebrates. In particular, it is not known which domains are responsible for the Tcf subtype specific functions. We investigated the conserved and non-conserved functions of the various Tcfs by using Xenopus laevis as a model organism and testing Tcfs from Hydra magnipapillata, Caenorhabditis elegans and Drosophila melanogaster. In order to identify domains relevant for the individual properties we created series of chimeric constructs consisting of parts of XTcf-3, XTcf-1 and HyTcf. Rescue experiments in Xenopus morphants revealed that the three invertebrate Tcfs tested compensated the loss of distinct Xenopus Tcfs: Drosophila Tcf (Pangolin) can substitute for the loss of XTcf-1, XTcf-3 and XTcf-4. By comparison, Caenorhabditis Tcf (Pop-1) and Hydra Tcf (HyTcf) can substitute for the loss of only XTcf-3 and XTcf-4, respectively. The domain, which is responsible for subtype specific functions is the regulatory CRD domain. A phylogenetic analysis separates Tcf-1/Lef-1 from the sister group Tcf-3/4 in the vertebrate lineage. We propose that the vertebrate specific diversification of Tcfs in vertebrates resulted in subfunctionalization of a Tcf that already united most of the Lef/Tcf functions. PMID:22641013

  19. The evolutionary origins of chordate hematopoiesis and vertebrate endothelia.

    PubMed

    Pascual-Anaya, Juan; Albuixech-Crespo, Beatriz; Somorjai, Ildikó Maureen Lara; Carmona, Rita; Oisi, Yasuhiro; Alvarez, Susana; Kuratani, Shigeru; Muñoz-Chápuli, Ramón; Garcia-Fernàndez, Jordi

    2013-03-15

    The vertebrate circulatory system is the most complex vascular system among those of metazoans, with key innovations including a multi-chambered heart and highly specialized blood cells. Invertebrate vessels, on the other hand, consist of hemal spaces between the basal laminae of epithelia. How the evolutionary transition from an invertebrate-type system to the complex vertebrate one occurred is, however, poorly understood. We investigate here the development of the cardiovascular system of the cephalochordate amphioxus Branchiostoma lanceolatum in order to gain insight into the origin of the vertebrate cardiovascular system. The cardiac markers Hand, Csx (Nkx2-5) and Tbx4/5 reveal a broad cardiac-like domain in amphioxus; such a decentralized organization during development parallels that seen in the adult anatomy. Our data therefore support the hypothesis that amphioxus never possessed a proper heart, even transiently during development. We also define a putative hematopoietic domain, supported by the expression of the hematopoietic markers Scl and Pdvegfr. We show that this area is closed to the dorsal aorta anlages, partially linked to excretory tissues, and that its development is regulated by retinoic acid, thus recalling the aorta-gonads-mesonephros (AGM) area of vertebrates. This region probably produces Pdvegfr+ hemal cells, with an important role in amphioxus vessel formation, since treatments with an inhibitor of PDGFR/VEGFR lead to a decrease of Laminin in the basal laminae of developing vessels. Our results point to a chordate origin of hematopoiesis in an AGM-like area from where hemal Pdvegfr+ cells are produced. These Pdvegfr+ cells probably resemble the ancestral chordate blood cells from which the vertebrate endothelium later originated. PMID:23201012

  20. Vertebrate POLQ and POLβ Cooperate in Base Excision Repair of Oxidative DNA Damage

    PubMed Central

    Yoshimura, Michio; Kohzaki, Masaoki; Nakamura, Jun; Asagoshi, Kenjiro; Sonoda, Eiichiro; Hou, Esther; Prasad, Rajendra; Wilson, Samuel H.; Tano, Keizo; Yasui, Akira; Lan, Li; Seki, Mineaki; Wood, Richard D.; Arakawa, Hiroshi; Buerstedde, Jean-Marie; Hochegger, Helfrid; Okada, Takashi; Hiraoka, Masahiro; Takeda, Shunichi

    2007-01-01

    Summary Base excision repair (BER) plays an essential role in protecting cells from mutagenic base damage caused by oxidative stress, hydrolysis, and environmental factors. POLQ is a DNA polymerase, which appears to be involved in translesion DNA synthesis (TLS) past base damage. We disrupted POLQ, and its homologs HEL308 and POLN in chicken DT40 cells, and also created polq/hel308 and polq/poln double mutants. We found that POLQ-deficient mutants exhibit hypersensitivity to oxidative base damage induced by H2O2, but not to UV or cisplatin. Surprisingly, this phenotype was synergistically increased by concomitant deletion of the major BER polymerase, POLβ. Moreover, extracts from a polq null mutant cell line show reduced BER activity, and POLQ, like POLβ, accumulated rapidly at sites of base damage. Accordingly, POLQ and POLβ share an overlapping function in the repair of oxidative base damage. Taken together, these results suggest a role for vertebrate POLQ in BER. PMID:17018297

  1. Mosquito immune responses and malaria transmission: lessons from insect model systems and implications for vertebrate innate immunity and vaccine development.

    PubMed

    Barillas-Mury, C; Wizel, B; Han, Y S

    2000-06-01

    The introduction of novel biochemical, genetic, molecular and cell biology tools to the study of insect immunity has generated an information explosion in recent years. Due to the biodiversity of insects, complementary model systems have been developed. The conceptual framework built based on these systems is used to discuss our current understanding of mosquito immune responses and their implications for malaria transmission. The areas of insect and vertebrate innate immunity are merging as new information confirms the remarkable extent of the evolutionary conservation, at a molecular level, in the signaling pathways mediating these responses in such distant species. Our current understanding of the molecular language that allows the vertebrate innate immune system to identify parasites, such as malaria, and direct the acquired immune system to mount a protective immune response is very limited. Insect vectors of parasitic diseases, such as mosquitoes, could represent excellent models to understand the molecular responses of epithelial cells to parasite invasion. This information could broaden our understanding of vertebrate responses to parasitic infection and could have extensive implications for anti-malarial vaccine development. PMID:10802234

  2. Posterior internal fixation plus vertebral bone implantation under navigational aid for thoracolumbar fracture treatment

    PubMed Central

    ZHOU, WEI; KONG, WEIQING; ZHAO, BIZHEN; FU, YISHAN; ZHANG, TAO; XU, JIANGUANG

    2013-01-01

    The aim of this study was to investigate the method of posterior thoracolumbar vertebral pedicle screw reduction and fixation combined with vertebral bone implantation via the affected vertebral body under navigational aid for the treatment of thoracolumbar fractures. The efficacy of the procedure was also measured. Between June 2005 and March 2011, posterior thoracolumbar vertebral pedicle screw reduction and fixation plus artificial bone implantation via the affected vertebral pedicle under navigational aid was used to treat 30 patients with thoracolumbar fractures, including 18 males and 12 females, ranging in age from 21 to 57 years. Compared with the values prior to surgery, intraspinal occupation, vertebral height ratio and Cobb angle at the follow-up were significantly improved. At the long-term follow-up, the postoperative Cobb angle loss was <1° and the anterior vertebral body height loss was <2 mm. Posterior thoracolumbar vertebral pedicle screw reduction and fixation combined with vertebral bone implantation via the affected vertebral body under navigational aid may increase the accuracy and safety of surgery, and it is an ideal method of internal implantation. Bone implantation via the affected vertebral body may increase vertebral stability. PMID:23935737

  3. Vocal Corollary Discharge Communicates Call Duration to Vertebrate Auditory System

    PubMed Central

    2013-01-01

    Corollary discharge is essential to an animal's ability to filter self-generated from external stimuli. This includes acoustic communication, although direct demonstration of a corollary discharge that both conveys a vocal motor signal and informs the auditory system about the physical attributes of a self-generated vocalization has remained elusive for vertebrates. Here, we show the underlying synaptic activity of a neuronal vocal corollary discharge pathway in the hindbrain of a highly vocal species of fish. Neurons carrying the vocal corollary discharge are specifically adapted for the transmission of duration information, a predominant acoustic cue. The results reveal that vertebrates, like some insects, have a robust corollary discharge conveying call duration. Along with evidence for the influence of vocal duration on auditory encoding in mammals, these new findings suggest that linking vocal motor and corollary discharge pathways with pattern generating, call duration neurons is a shared network character across the animal kingdom. PMID:24285884

  4. 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

  5. The Current Status of Vertebrate Cellular mRNA IRESs

    PubMed Central

    Jackson, Richard J.

    2013-01-01

    Internal ribosome entry sites/segments (IRESs) were first discovered over 20 years ago in picornaviruses, followed by the discovery of two other types of IRES in hepatitis C virus (HCV), and the dicistroviruses, which infect invertebrates. In the meantime, reports of IRESs in eukaryotic cellular mRNAs started to appear, and the list of such putative IRESs continues to grow to the point in which it now stands at ∼100, 80% of them in vertebrate mRNAs. Despite initial skepticism from some quarters, there now seems universal agreement that there is genuine internal ribosome entry on the viral IRESs. However, the same cannot be said for cellular mRNA IRESs, which continue to be shrouded in controversy. The aim of this article is to explain why vertebrate mRNA IRESs remain controversial, and to discuss ways in which these controversies might be resolved. PMID:23378589

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

    PubMed

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

    2016-04-26

    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

  7. Comparative transcriptome analysis reveals vertebrate phylotypic period during organogenesis

    PubMed Central

    Irie, Naoki; Kuratani, Shigeru

    2011-01-01

    One of the central issues in evolutionary developmental biology is how we can formulate the relationships between evolutionary and developmental processes. Two major models have been proposed: the 'funnel-like' model, in which the earliest embryo shows the most conserved morphological pattern, followed by diversifying later stages, and the 'hourglass' model, in which constraints are imposed to conserve organogenesis stages, which is called the phylotypic period. Here we perform a quantitative comparative transcriptome analysis of several model vertebrate embryos and show that the pharyngula stage is most conserved, whereas earlier and later stages are rather divergent. These results allow us to predict approximate developmental timetables between different species, and indicate that pharyngula embryos have the most conserved gene expression profiles, which may be the source of the basic body plan of vertebrates. PMID:21427719

  8. Blunt Abdominal Aortic Injury Associated with L2 Vertebral Fracture.

    PubMed

    Yoshioka, Yuki; Morimoto, Yoshihisa; Sugimoto, Takaki; Arase, Hiroki; Araki, Kota

    2016-07-01

    Blunt abdominal aortic injury (BAAI) is very rare. In general, BAAI occurs in high-energy accidents. Here, we present a case of BAAI in a low-energy accident. A 70-year-old female was injured after falling 3 m. Her vital signs were stable. She had lumbar fractures (L1, L2) and BAAI associated with a fragment of the fractured L2 vertebral body. On the fifth posttrauma day, we performed an operation because computed tomography showed a bone fragment of the lumbar fractures (L1, L2) threatening the abdominal aorta. The aortic injury site was transected, and the fragment of the L2 vertebral body was removed. Even in low-energy accidents, BAAI should be considered. BAAI with stable vital signs can be electively treated. PMID:27126715

  9. Diagnosis of hematogenous pyogenic vertebral osteomyelitis by magnetic resonance imaging

    SciTech Connect

    Meyers, S.P.; Wiener, S.N. )

    1991-04-01

    The clinical information and imaging data from 27 patients with hematogenous pyogenic vertebral osteomyelitis were reviewed. All patients had roentgenographic and magnetic resonance imaging examinations. Seventeen patients had computed tomograms; 17 had technetium Tc 99m medronate bone scans; and seven had gallium citrate Ga 67 scans. Magnetic resonance imaging, when used as a part of the initial radiologic evaluation, detected abnormalities consistent with osteomyelitis in all 27 patients. Magnetic resonance imaging also demonstrated paravertebral and/or epidural extension of infection in 14 patients, including seven patients who had neurologic signs of lower-extremity weakness. Roentgenograms, computed tomograms, technetium bone scans, and gallium scans had findings suggestive of the diagnosis in 48%, 65%, 71%, and 86% of the patients, respectively. We recommend magnetic resonance imaging as an important and perhaps critical imaging modality for detection of pyogenic vertebral osteomyelitis.

  10. Allelochemical communication in vertebrates: kairomones, allomones and synomones.

    PubMed

    Sbarbati, A; Osculati, F

    2006-01-01

    Communication between different species by means of chemicals (allelomones) is widespread among prokaryotes, plants and invertebrates. This study reviews data suggesting that allelochemically mediated communication also exists among vertebrates. The work aims to provide a concise, interdisciplinary review of communication mediated by infochemicals, with a focus on interspecies and interkingdom signaling. A definition of infochemicals is given, with a brief review of the general principles of chemical communication in different kingdoms in nature. Findings are reported which suggest that interspecies chemical signaling is important for vertebrates also. It is proposed that the general laws of chemical ecology are valid for mammals too, and that the terms indicating the different types of allelomones (i.e. kairomone, allomone and synomone) might also be used in medicine. In particular, the microchemical environment at the airway and digestive interfaces are discussed from an infochemical point of view. PMID:17159346

  11. Risk Factors for Vertebral Artery Injuries in Cervical Spine Trauma

    PubMed Central

    Dabke, Harshad V.

    2014-01-01

    Blunt cerebrovascular injuries (i.e. involvement of carotid and vertebral arteries) are increasingly being recognized in setting of cervical spine trauma/fractures and are associated with high incidence of stroke/morbidity and mortality. The incidence of vertebral artery injuries (VAI) is more common than previously thought and regular screening is seldom performed. However there exists no screening criteria and conflicting reports exists between spine and trauma literature. Many clinicians do not routinely screen/evaluate patients presenting with cervical spine trauma for potential VAI. This article provides a brief summary of existing evidence regarding the incidence of VAI in the background of cervical trauma/fractures. The type and fracture pattern that is associated with a high risk of VAI warranting mandatory screening/further work-up is discussed. A brief overview of diagnostic modalities and their respective sensitivity/specificity along with available treatment options is also summarized. PMID:25317310

  12. Worlds within worlds: evolution of the vertebrate gut microbiota

    PubMed Central

    Ley, Ruth E.; Lozupone, Catherine A.; Hamady, Micah; Knight, Rob

    2009-01-01

    Here we use published 16S rRNA gene sequences to compare the bacterial assemblages associated with humans, other mammals, other metazoa, and free-living microbial communities spanning a range of environmental conditions. The composition of the vertebrate gut microbiota is influenced by diet, host morphology and phylogeny, and in this respect the human gut bacterial community is typical for an omnivorous primate. However, a wider view reveals that the vertebrate gut microbiota is highly differentiated from free-living communities not associated with animal body habitats. The recently initiated international Human Microbiome Project should strive to include a broad representation of humans, as well as other mammals and environmental samples: comparative analyses of microbiotas and their microbiomes are a powerful way to explore the evolutionary history of the biosphere. PMID:18794915

  13. An aggressive vertebral hemangioma in pregnancy: a case report

    PubMed Central

    2014-01-01

    Introduction Pregnancy-related compressive myelopathy secondary to vertebral hemangioma is a rare occurrence and its treatment antepartum is rare. Case presentation A 19-year-old North African woman in her 38th week of pregnancy presented with paraplegia that progressed within 2 days after a rapidly progressive weakness of her lower limbs. Magnetic resonance imaging studies showed compression of her spinal cord in front of the fourth thoracic vertebra for suspected tuberculous spondylitis. A Caesarean section was done followed by corpectomy with a bone graft because we intraoperatively discovered a vertebral hemangioma. Pathology showed an aggressive hemangioma. Conclusion At any term of pregnancy, extensive neurological involvement which is rapidly progressive due to compression should be considered for immediate decompression. PMID:24943121

  14. Vertebral artery thrombosis: a rare presentation of primary polycythaemia

    PubMed Central

    Gul, H L; Lau, S Y M; Chan-Lam, D; Ng, J-P

    2014-01-01

    Primary polycythaemia, also known as polycythaemia vera (PV), is a myeloproliferative neoplasm (MPN) which is associated with arterial and venous thrombosis and which can contribute to significant morbidity and mortality if untreated. Arterial thrombosis accounts for a large proportion of PV-related thrombotic events which may manifest as stroke and myocardial infarction. There is an abundance of literature documenting thrombosis arising in the cerebral vasculature secondary to PV. However, vertebral artery thrombosis associated with PV has not been previously described. We present a case of vertebral artery thrombosis as the presenting manifestation of PV. This case demonstrates the importance of recognising MPNs as a cause of an unusual presentation of thrombosis. PMID:24862411

  15. Vertebral Dissecting Aneurysm Treated with Wingspan Stent Deployment and Detachable Coils

    PubMed Central

    Lv, M.; Lv, X.; Li, Y.; Yang, X.; Wu, Z.

    2009-01-01

    Summary We describe the first documented endovascular treatment of vertebral dissecting aneurysm using a Wingspan stent and detachable coils. A 54-year-old man presented with a nonruptured vertebral dissecting aneurysm. Because of the dissecting nature of the vertebral aneurysms, a 3x15-mm Wingspan stent was placed in the left vertebral artery. One month later, several detachable coils were introduced into the aneurysm. Six-month follow-up angiogram confirmed the obliteration. Vertebral dissecting aneurysm can be treated with Wingspan stent placement and detachable coils. PMID:20465940

  16. The Spectrum of Recovery From Fracture-Induced Vertebral Deformity in Pediatric Leukemia.

    PubMed

    Dal Osto, Leo C; Konji, Victor N; Halton, Jacqueline; Matzinger, Mary Ann; Bassal, Mylène; Rauch, Frank; Ward, Leanne M

    2016-06-01

    Vertebral fractures (VF) are a frequent complication of acute lymphoblastic leukemia. Some children with VF undergo vertebral body reshaping to the point of complete restoration of normal vertebral dimensions. Others are left with permanent vertebral deformity if the degree of reshaping has been incomplete by the time of final adult height attainment. In this report, we describe three children with painful VF at leukemia diagnosis or during chemotherapy. Each patient highlights different clinical trajectories in their recovery from VF and underscores the need for osteoporosis intervention trials with the goal to prevent permanent vertebral deformity in selected patients. PMID:26878592

  17. Vertebral hyperemia associated with bone marrow insult and recovery

    SciTech Connect

    Klein, H.A.; Bolden, R.O.; Simone, F.J.

    1984-06-01

    A 15-year-old boy with rhabdoid sarcoma received chemotherapy, which was followed by bone marrow depression, massive nosebleeds and, finally, hematologic recovery. On both hepatobiliary and renal scintigraphy, prominent vertebral activity was present in early images. Correlation with his clinical course suggests that the findings reflect hyperemia due to marrow insult and recovery. Radionuclide imaging to detect hyperemia may be a useful probe for drug effects on hematopoietic bone marrow.

  18. Vertebrate seed dispersers maintain the composition of tropical forest seedbanks

    PubMed Central

    Wandrag, E. M.; Dunham, A. E.; Miller, R. H.; Rogers, H. S.

    2015-01-01

    The accumulation of seeds in the soil (the seedbank) can set the template for the early regeneration of habitats following disturbance. Seed dispersal is an important factor determining the pattern of seed rain, which affects the interactions those seeds experience. For this reason, seed dispersal should play an important role in structuring forest seedbanks, yet we know little about how that happens. Using the functional extirpation of frugivorous vertebrates from the island of Guam, together with two nearby islands (Saipan and Rota) that each support relatively intact disperser assemblages, we aimed to identify the role of vertebrate dispersers in structuring forest seedbanks. We sampled the seedbank on Guam where dispersers are absent, and compared this with the seedbank on Saipan and Rota where they are present. Almost twice as many species found in the seedbank on Guam, when compared with Saipan and Rota, had a conspecific adult within 2 m. This indicates a strong role of vertebrate dispersal in determining the identity of seeds in the seedbank. In addition, on Guam, a greater proportion of samples contained no seeds and overall species richness was lower than on Saipan. Differences in seed abundance and richness between Guam and Rota were less clear, as seedbanks on Rota also contained fewer species than Saipan, possibly due to increased post-dispersal seed predation. Our findings suggest that vertebrate seed dispersers can have a strong influence on the species composition of seedbanks. Regardless of post-dispersal processes, without dispersal, seedbanks no longer serve to increase the species pool of recruits during regeneration. PMID:26578741

  19. Membranes, minerals, and proteins of developing vertebrate enamel.

    PubMed

    Diekwisch, Thomas G H; Berman, Brett J; Anderton, Xochitl; Gurinsky, Brian; Ortega, Adam J; Satchell, Paul G; Williams, Mia; Arumugham, Chithra; Luan, Xianghong; McIntosh, James E; Yamane, Akira; Carlson, David S; Sire, Jean-Yves; Shuler, Charles F

    2002-12-01

    Developing tooth enamel is formed as organized mineral in a specialized protein matrix. In order to analyze patterns of enamel mineralization and enamel protein expression in species representative of the main extant vertebrate lineages, we investigated developing teeth in a chondrichthyan, the horn shark, a teleost, the guppy, a urodele amphibian, the Mexican axolotl, an anuran amphibian, the leopard frog, two lepidosauria, a gecko and an iguana, and two mammals, a marsupial, the South American short-tailed gray opossum, and the house mouse. Electron microscopic analysis documented the presence of a distinct basal lamina in all species investigated. Subsequent stages of enamel biomineralization featured highly organized long and parallel enamel crystals in mammals, lepidosaurians, the frog, and the shark, while amorphous mineral deposits and/or randomly oriented crystals were observed in the guppy and the axolotl. In situ hybridization using a full-length mouse probe for amelogenin mRNA resulted in amelogenin specific signals in mouse, opossum, gecko, frog, axolotl, and shark. Using immunohistochemistry, amelogenin and tuftelin enamel proteins were detected in the enamel organ of many species investigated, but tuftelin epitopes were also found in other tissues. The anti-M179 antibody, however, did not react with the guppy and axolotl enameloid matrix. We conclude that basic features of vertebrate enamel/enameloid formation such as the presence of enamel proteins or the mineral deposition along the dentin-enamel junction were highly conserved in vertebrates. There were also differences in terms of enamel protein distribution and mineral organization between the vertebrates lineages. Our findings indicated a correlation between the presence of amelogenins and the presence of long and parallel hydroxyapatite crystals in tetrapods and shark. PMID:12430167

  20. New insights into the vertebral Hox code of archosaurs.

    PubMed

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

    2015-01-01

    Variation in axial formulae (i.e., number and identity of vertebrae) is an important feature in the evolution of vertebrates. Vertebrae at different axial positions exhibit a region-specific morphology. Key determinants for the establishment of particular vertebral shapes are the highly conserved Hox genes. Here, we analyzed Hox gene expression in the presacral vertebral column in the Nile crocodile in order to complement and extend a previous examination in the alligator and thus establish a Hox code for the axial skeleton of crocodilians in general. The newly determined expression of HoxA-4, C-5, B-7, and B-8 all revealed a crocodilian-specific pattern. HoxA-4 and HoxC-5 characterize cervical morphologies and the latter furthermore is associated with the position of the forelimb relative to the axial skeleton. HoxB-7 and HoxB-8 map exclusively to the dorsal vertebral region. The resulting expression patterns of these two Hox genes is the first description of their exact expression in the archosaurian embryo. Our comparative analyses of the Hox code in several amniote taxa provide new evidence that evolutionary differences in the axial skeleton correspond to changes in Hox gene expression domains. We detect two general processes: (i) expansion of a Hox gene's expression domain as well as (ii) a shift of gene expression. We infer that the ancestral archosaur Hox code may have resembled that of the crocodile. In association with the evolution of morphological traits, it may have been modified to patterns that can be observed in birds. PMID:26372060

  1. Differential use of salmon by vertebrate consumers: implications for conservation.

    PubMed

    Levi, Taal; Wheat, Rachel E; Allen, Jennifer M; Wilmers, Christopher C

    2015-01-01

    Salmon and other anadromous fish are consumed by vertebrates with distinct life history strategies to capitalize on this ephemeral pulse of resource availability. Depending on the timing of salmon arrival, this resource may be in surplus to the needs of vertebrate consumers if, for instance, their populations are limited by food availability during other times of year. However, the life history of some consumers enables more efficient exploitation of these ephemeral resources. Bears can deposit fat and then hibernate to avoid winter food scarcity, and highly mobile consumers such as eagles, gulls, and other birds can migrate to access asynchronous pulses of salmon availability. We used camera traps on pink, chum, and sockeye salmon spawning grounds with various run times and stream morphologies, and on individual salmon carcasses, to discern potentially different use patterns among consumers. Wildlife use of salmon was highly heterogeneous. Ravens were the only avian consumer that fed heavily on pink salmon in small streams. Eagles and gulls did not feed on early pink salmon runs in streams, and only moderately at early sockeye runs, but were the dominant consumers at late chum salmon runs, particularly on expansive river flats. Brown bears used all salmon resources far more than other terrestrial vertebrates. Notably, black bears were not observed on salmon spawning grounds despite being the most frequently observed vertebrate on roads and trails. From a conservation and management perspective, all salmon species and stream morphologies are used extensively by bears, but salmon spawning late in the year are disproportionately important to eagles and other highly mobile species that are seasonally limited by winter food availability. PMID:26339539

  2. Rapid progress on the vertebrate tree of life

    PubMed Central

    2010-01-01

    Background Among the greatest challenges for biology in the 21st century is inference of the tree of life. Interest in, and progress toward, this goal has increased dramatically with the growing availability of molecular sequence data. However, we have very little sense, for any major clade, of how much progress has been made in resolving a full tree of life and the scope of work that remains. A series of challenges stand in the way of completing this task but, at the most basic level, progress is limited by data: a limited fraction of the world's biodiversity has been incorporated into a phylogenetic analysis. More troubling is our poor understanding of what fraction of the tree of life is understood and how quickly research is adding to this knowledge. Here we measure the rate of progress on the tree of life for one clade of particular research interest, the vertebrates. Results Using an automated phylogenetic approach, we analyse all available molecular data for a large sample of vertebrate diversity, comprising nearly 12,000 species and 210,000 sequences. Our results indicate that progress has been rapid, increasing polynomially during the age of molecular systematics. It is also skewed, with birds and mammals receiving the most attention and marine organisms accumulating far fewer data and a slower rate of increase in phylogenetic resolution than terrestrial taxa. We analyse the contributors to this phylogenetic progress and make recommendations for future work. Conclusions Our analyses suggest that a large majority of the vertebrate tree of life will: (1) be resolved within the next few decades; (2) identify specific data collection strategies that may help to spur future progress; and (3) identify branches of the vertebrate tree of life in need of increased research effort. PMID:20211001

  3. Severe spontaneous vertebral fractures after denosumab discontinuation: three case reports.

    PubMed

    Aubry-Rozier, B; Gonzalez-Rodriguez, E; Stoll, D; Lamy, O

    2016-05-01

    Osteoporosis treatments are usually given for a limited period of time in order to balance benefits and risks. We report three cases of postmenopausal women without any previous fragility fracture who presented severe spontaneous vertebral fractures after denosumab discontinuation. We think that the occurrence of these fractures could be explained by the severe rebound effect observed after denosumab discontinuation and that a consensus regarding the end of treatment with denosumab has to be defined. PMID:26510845

  4. Vertebrate seed dispersers maintain the composition of tropical forest seedbanks.

    PubMed

    Wandrag, E M; Dunham, A E; Miller, R H; Rogers, H S

    2015-01-01

    The accumulation of seeds in the soil (the seedbank) can set the template for the early regeneration of habitats following disturbance. Seed dispersal is an important factor determining the pattern of seed rain, which affects the interactions those seeds experience. For this reason, seed dispersal should play an important role in structuring forest seedbanks, yet we know little about how that happens. Using the functional extirpation of frugivorous vertebrates from the island of Guam, together with two nearby islands (Saipan and Rota) that each support relatively intact disperser assemblages, we aimed to identify the role of vertebrate dispersers in structuring forest seedbanks. We sampled the seedbank on Guam where dispersers are absent, and compared this with the seedbank on Saipan and Rota where they are present. Almost twice as many species found in the seedbank on Guam, when compared with Saipan and Rota, had a conspecific adult within 2 m. This indicates a strong role of vertebrate dispersal in determining the identity of seeds in the seedbank. In addition, on Guam, a greater proportion of samples contained no seeds and overall species richness was lower than on Saipan. Differences in seed abundance and richness between Guam and Rota were less clear, as seedbanks on Rota also contained fewer species than Saipan, possibly due to increased post-dispersal seed predation. Our findings suggest that vertebrate seed dispersers can have a strong influence on the species composition of seedbanks. Regardless of post-dispersal processes, without dispersal, seedbanks no longer serve to increase the species pool of recruits during regeneration. PMID:26578741

  5. Partitioning sources of variation in vertebrate species richness

    USGS Publications Warehouse

    Boone, R.B.; Krohn, W.B.

    2000-01-01

    Aim: To explore biogeographic patterns of terrestrial vertebrates in Maine, USA using techniques that would describe local and spatial correlations with the environment. Location: Maine, USA. Methods: We delineated the ranges within Maine (86,156 km2) of 275 species using literature and expert review. Ranges were combined into species richness maps, and compared to geomorphology, climate, and woody plant distributions. Methods were adapted that compared richness of all vertebrate classes to each environmental correlate, rather than assessing a single explanatory theory. We partitioned variation in species richness into components using tree and multiple linear regression. Methods were used that allowed for useful comparisons between tree and linear regression results. For both methods we partitioned variation into broad-scale (spatially autocorrelated) and fine-scale (spatially uncorrelated) explained and unexplained components. By partitioning variance, and using both tree and linear regression in analyses, we explored the degree of variation in species richness for each vertebrate group that Could be explained by the relative contribution of each environmental variable. Results: In tree regression, climate variation explained richness better (92% of mean deviance explained for all species) than woody plant variation (87%) and geomorphology (86%). Reptiles were highly correlated with environmental variation (93%), followed by mammals, amphibians, and birds (each with 84-82% deviance explained). In multiple linear regression, climate was most closely associated with total vertebrate richness (78%), followed by woody plants (67%) and geomorphology (56%). Again, reptiles were closely correlated with the environment (95%), followed by mammals (73%), amphibians (63%) and birds (57%). Main conclusions: Comparing variation explained using tree and multiple linear regression quantified the importance of nonlinear relationships and local interactions between species

  6. Vertebrate fatty acyl desaturase with Δ4 activity

    PubMed Central

    Li, Yuanyou; Monroig, Oscar; Zhang, Liang; Wang, Shuqi; Zheng, Xiaozhong; Dick, James R.; You, Cuihong; Tocher, Douglas R.

    2010-01-01

    Biosynthesis of the highly biologically active long-chain polyunsaturated fatty acids, arachidonic (ARA), eicosapentaenoic (EPA), and docosahexaenoic (DHA) acids, in vertebrates requires the introduction of up to three double bonds catalyzed by fatty acyl desaturases (Fad). Synthesis of ARA is achieved by Δ6 desaturation of 18∶2n - 6 to produce 18∶3n - 6 that is elongated to 20∶3n - 6 followed by Δ5 desaturation. Synthesis of EPA from 18∶3n - 3 requires the same enzymes and pathway as for ARA, but DHA synthesis reportedly requires two further elongations, a second Δ6 desaturation and a peroxisomal chain shortening step. This paper describes cDNAs, fad1 and fad2, isolated from the herbivorous, marine teleost fish (Siganus canaliculatus) with high similarity to mammalian Fad proteins. Functional characterization of the cDNAs by heterologous expression in the yeast Saccharomyces cerevisiae showed that Fad1 was a bifunctional Δ6/Δ5 Fad. Previously, functional dual specificity in vertebrates had been demonstrated for a zebrafish Danio rerio Fad and baboon Fad, so the present report suggests bifunctionality may be more widespread in vertebrates. However, Fad2 conferred on the yeast the ability to convert 22∶5n - 3 to DHA indicating that this S. canaliculatus gene encoded an enzyme having Δ4 Fad activity. This is a unique report of a Fad with Δ4 activity in any vertebrate species and indicates that there are two possible mechanisms for DHA biosynthesis, a direct route involving elongation of EPA to 22∶5n - 3 followed by Δ4 desaturation, as well as the more complicated pathway as described above. PMID:20826444

  7. Comparative anatomy of the vestibular nuclear complex in submammalian vertebrates.

    NASA Technical Reports Server (NTRS)

    Mehler, W. R.

    1972-01-01

    A synopsis of the literature on the natural history of the vestibular nuclear complex (VNC) in lower vertebrates is presented in an attempt to assess the knowledge available. The review discloses that there is considerable descriptive information that is widely dispersed in the literature. However, information about the topology, number, and cellular composition of the cell groups that compose the VNC is sketchy. Major cytological and hodological information is still needed to establish which parts of the VNC actually are homologous.

  8. Double Cones as a Basis for Polarization Sensitivity in Vertebrates

    NASA Astrophysics Data System (ADS)

    Rowe, Manoel

    1995-01-01

    Over the course of the past 50 years there has been an increasing number of claims that certain vertebrates are sensitive to the linear polarization state of visible radiation. However, the mechanism(s) that mediates this polarization sensitivity remains elusive at the present time. The retinas of most vertebrates contain anatomical structures loosely referred to as double cones--composite entities constituted by the apposition of two independently developed, diurnally active photoreceptors. The significance of this apposition for visual function also remains elusive. It is possible that double cones mediate polarization sensitivity as a consequence of geometric birefringence; light polarized parallel to the axis joining the centers of the two halves of a double cone can potentially stimulate the receptors more strongly than light polarized in the direction perpendicular to both that axis and the normal axis of light propagation down the length of the double cone. The feasibility of this mechanism for polarization sensitivity has been examined here with specific reference to the retina of a representative animal, the green sunfish (Lepomis cyanellus). Transmission electron micrographs of thin sections from a sunfish retina were analyzed in order to develop simple models of waveguiding down the long axis of a sunfish double cone. The results of the computations indicate that the mechanism is feasible only if there are refractive index gradients in the photoreceptors of sunfish. Isolated receptors were thus examined with scanning microinterferometry to demonstrate the presence of such gradients. In the course of the investigation, the literature pertaining to vertebrate polarization sensitivity and retinal anatomy were reviewed to delimit the generality of the conclusions drawn from sunfish photoreceptors. As a result of this analysis, it should be concluded that much future research is needed to clarify what (if any) role optical polarization plays in the sensory

  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. PMID:26706913

  10. Differential use of salmon by vertebrate consumers: implications for conservation

    PubMed Central

    Wheat, Rachel E.; Allen, Jennifer M.; Wilmers, Christopher C.

    2015-01-01

    Salmon and other anadromous fish are consumed by vertebrates with distinct life history strategies to capitalize on this ephemeral pulse of resource availability. Depending on the timing of salmon arrival, this resource may be in surplus to the needs of vertebrate consumers if, for instance, their populations are limited by food availability during other times of year. However, the life history of some consumers enables more efficient exploitation of these ephemeral resources. Bears can deposit fat and then hibernate to avoid winter food scarcity, and highly mobile consumers such as eagles, gulls, and other birds can migrate to access asynchronous pulses of salmon availability. We used camera traps on pink, chum, and sockeye salmon spawning grounds with various run times and stream morphologies, and on individual salmon carcasses, to discern potentially different use patterns among consumers. Wildlife use of salmon was highly heterogeneous. Ravens were the only avian consumer that fed heavily on pink salmon in small streams. Eagles and gulls did not feed on early pink salmon runs in streams, and only moderately at early sockeye runs, but were the dominant consumers at late chum salmon runs, particularly on expansive river flats. Brown bears used all salmon resources far more than other terrestrial vertebrates. Notably, black bears were not observed on salmon spawning grounds despite being the most frequently observed vertebrate on roads and trails. From a conservation and management perspective, all salmon species and stream morphologies are used extensively by bears, but salmon spawning late in the year are disproportionately important to eagles and other highly mobile species that are seasonally limited by winter food availability. PMID:26339539

  11. 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

  12. ELF communications system ecological monitoring program. Small vertebrate studies

    NASA Astrophysics Data System (ADS)

    Beaver, Donald L.; Hill, Richard W.; Hill, Susan D.

    1994-10-01

    The U.S. Navy has completed a program monitoring flora, fauna, and ecological relationships tor possible effects from electromagnetic fields produced by its Extremely Low Frequency (ELF) Communications System. This report documents studies of small mammals and nesting birds conducted near its transmitting antenna in Michigan. From 1982 through 1993 researchers from the Michigan State University (MSU) monitored organismal and population aspects of vertebrates in areas near (treatment) and far (control) from the Michigan antenna. They examined the reproductive, developmental, behavioral, and physiological characteristics of representative vertebrate species. Studied species were the deer mouse, chipmunk, tree swallow, and blackcapped - chickadee. Investigators had also monitored ecological aspects of the mammalian community until 1988 when this study element was discontinued due to highly variable results. In a different project, ornithologists from the University of Minnesota-Duluth monitored the ecological characteristics of the bird community near the ELF System. The MSU research team used several statistical tests to examine data; however, nested analysis of variance was the most often used test. Based on the results of their study, they conclude that the EM fields produced by the Naval Radio Transmitting Facility-Republic, Michigan did not affect small vertebrates.

  13. Evolutionary Dynamics of Rhodopsin Type 2 Opsins in Vertebrates

    PubMed Central

    Yokoyama, Shozo; Tada, Takashi

    2010-01-01

    Among the five groups of visual pigments in vertebrates, the rhodopsin type 2 (RH2) group shows the largest number of gene duplication events. We have isolated three intact and one nonfunctional RH2 opsin genes each from Northern lampfish (Stenobrachius leucopsarus) and scabbardfish (Lepidopus fitchi). Using the deduced amino acid sequences of these and other representative RH2 opsin genes in vertebrates, we have estimated the divergence times and evolutionary rates of amino acid substitution at various stages of RH2 opsin evolution. The results show that the duplications of the lampfish and scabbardfish RH2 opsins have occurred ∼60 and ∼30 million years ago (Ma), respectively. The evolutionary rates of RH2 opsins in the early vertebrate ancestors were ∼0.25 × 10−9/site/year, which increased to ∼1 × 10−9 to 3 × 10−9/site/year in euteleost lineages and to ∼0.3 × 10−9 to 0.5 × 10−9/site/year in coelacanth and tetrapods. PMID:19759234

  14. Meis homeoproteins directly regulate Pax6 during vertebrate lens morphogenesis

    PubMed Central

    Zhang, Xin; Friedman, Adam; Heaney, Shaun; Purcell, Patricia; Maas, Richard L.

    2002-01-01

    Pax6 is a pivotal regulator of eye development throughout Metazoa, but the direct upstream regulators of vertebrate Pax6 expression are unknown. In vertebrates, Pax6 is required for formation of the lens placode, an ectodermal thickening that precedes lens development. Here we show that the Meis1 and Meis2 homeoproteins are direct regulators of Pax6 expression in prospective lens ectoderm. In mice, Meis1 and Meis2 are developmentally expressed in a pattern remarkably similar to Pax6 and their expression is Pax6-independent. Biochemical and transgenic experiments reveal that Meis1 and Meis2 bind a specific sequence in the Pax6 lens placode enhancer that is required for its activity. Furthermore, Pax6 and Meis2 exhibit a strong genetic interaction in lens development, and Pax6 expression is elevated in lenses of Meis2-overexpressing transgenic mice. When expressed in embryonic lens ectoderm, dominant-negative forms of Meis down-regulate endogenous Pax6. These results contrast with those in Drosophila, where the single Meis homolog, Homothorax, has been shown to negatively regulate eye formation. Therefore, despite the striking evolutionary conservation of Pax6 function, Pax6 expression in the vertebrate lens is uniquely regulated. PMID:12183364

  15. The evolution of the vertebrate Dlx gene family.

    PubMed Central

    Stock, D W; Ellies, D L; Zhao, Z; Ekker, M; Ruddle, F H; Weiss, K M

    1996-01-01

    The vertebrate Dlx gene family consists of homeobox-containing transcription factors distributed in pairs on the same chromosomes as the Hox genes. To investigate the evolutionary history of Dlx genes, we have cloned five new zebrafish family members and have provided additional sequence information for two mouse genes. Phylogenetic analyses of Dlx gene sequences considered in the context of their chromosomal arrangements suggest that an initial tandem duplication produced a linked pair of Dlx genes after the divergence of chordates and arthropods but prior to the divergence of tunicates and vertebrates. This pair of Dlx genes was then duplicated in the chromosomal events that led to the four clusters of Hox genes characteristic of bony fish and tetrapods. It is possible that a pair of Dlx genes linked to the Hoxc cluster has been lost from mammals. We were unable to distinguish between independent duplication and retention of the ancestral state of bony vertebrates to explain the presence of a greater number of Dlx genes in zebrafish than mammals. Determination of the linkage relationship of these additional zebrafish Dlx genes to Hox clusters should help resolve this issue. PMID:8855272

  16. Evolutionary genomics of immunoglobulin-encoding Loci in vertebrates.

    PubMed

    Das, Sabyasachi; Hirano, Masayuki; Tako, Rea; McCallister, Chelsea; Nikolaidis, Nikolas

    2012-04-01

    Immunoglobulins (or antibodies) are an essential element of the jawed vertebrate adaptive immune response system. These molecules have evolved over the past 500 million years and generated highly specialized proteins that recognize an extraordinarily large number of diverse substances, collectively known as antigens. During vertebrate evolution the diversification of the immunoglobulin-encoding loci resulted in differences in the genomic organization, gene content, and ratio of functional genes and pseudogenes. The tinkering process in the immunoglobulin-encoding loci often gave rise to lineage-specific characteristics that were formed by selection to increase species adaptation and fitness. Immunoglobulin loci and their encoded antibodies have been shaped repeatedly by contrasting evolutionary forces, either to conserve the prototypic structure and mechanism of action or to generate alternative and diversified structures and modes of function. Moreover, evolution favored the development of multiple mechanisms of primary and secondary antibody diversification, which are used by different species to effectively generate an almost infinite collection of diverse antibody types. This review summarizes our current knowledge on the genomics and evolution of the immunoglobulin-encoding loci and their protein products in jawed vertebrates. PMID:23024601

  17. The eyes of Tullimonstrum reveal a vertebrate affinity.

    PubMed

    Clements, Thomas; Dolocan, Andrei; Martin, Peter; Purnell, Mark A; Vinther, Jakob; Gabbott, Sarah E

    2016-04-28

    Tullimonstrum gregarium is an iconic soft-bodied fossil from the Carboniferous Mazon Creek Lagerstätte (Illinois, USA). Despite a large number of specimens and distinct anatomy, various analyses over the past five decades have failed to determine the phylogenetic affinities of the 'Tully monster', and although it has been allied to such disparate phyla as the Mollusca, Annelida or Chordata, it remains enigmatic. The nature and phylogenetic affinities of Tullimonstrum have defied confident systematic placement because none of its preserved anatomy provides unequivocal evidence of homology, without which comparative analysis fails. Here we show that the eyes of Tullimonstrum possess ultrastructural details indicating homology with vertebrate eyes. Anatomical analysis using scanning electron microscopy reveals that the eyes of Tullimonstrum preserve a retina defined by a thick sheet comprising distinct layers of spheroidal and cylindrical melanosomes. Time-of-flight secondary ion mass spectrometry and multivariate statistics provide further evidence that these microbodies are melanosomes. A range of animals have melanin in their eyes, but the possession of melanosomes of two distinct morphologies arranged in layers, forming retinal pigment epithelium, is a synapomorphy of vertebrates. Our analysis indicates that in addition to evidence of colour patterning, ecology and thermoregulation, fossil melanosomes can also carry a phylogenetic signal. Identification in Tullimonstrum of spheroidal and cylindrical melanosomes forming the remains of retinal pigment epithelium indicates that it is a vertebrate; considering its body parts in this new light suggests it was an anatomically unusual member of total group Vertebrata. PMID:27074512

  18. 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.

  19. Vertebrate diet decreases winter torpor use in a desert marsupial

    NASA Astrophysics Data System (ADS)

    Pavey, Chris R.; Burwell, Chris J.; Körtner, Gerhard; Geiser, Fritz

    2009-06-01

    One of the energetic benefits of daily torpor over prolonged hibernation is that it enables animals to regularly forage and, therefore, replenish food reserves between bouts of torpor. However, little is known about the diet of predators undergoing torpor or whether differences in prey composition among individuals influence torpor characteristics. Here, we test the hypothesis that prey composition affects winter torpor use and patterns of a population of carnivorous marsupial, the brush-tailed mulgara ( Dasycercus blythi), in the Great Sandy Desert, Australia. Mulgaras in the study population captured a wide range of prey including vertebrates (mammals, reptiles, birds), seven insect orders, spiders and centipedes. The proportion of vertebrates in the diet was negatively correlated with both frequency of torpor use and maximum bout duration. This variation in torpor use with diet can be explained by the higher energetic content of vertebrates as well as their larger size. Even assuming uniform intake of prey biomass among individuals, those that subsisted on an invertebrate-dominated diet during winter apparently suffered energetic shortages as a result of the scarcity of invertebrate taxa with high energy content (such as insect larvae). Our study is the first to demonstrate a link between diet composition and daily torpor use in a free-ranging mammal.

  20. 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

  1. The evolution of nasal immune systems in vertebrates.

    PubMed

    Sepahi, Ali; Salinas, Irene

    2016-01-01

    The olfactory organs of vertebrates are not only extraordinary chemosensory organs but also a powerful defense system against infection. Nasopharynx-associated lymphoid tissue (NALT) has been traditionally considered as the first line of defense against inhaled antigens in birds and mammals. Novel work in early vertebrates such as teleost fish has expanded our view of nasal immune systems, now recognized to fight both water-borne and air-borne pathogens reaching the olfactory epithelium. Like other mucosa-associated lymphoid tissues (MALT), NALT of birds and mammals is composed of organized lymphoid tissue (O-NALT) (i.e., tonsils) as well as a diffuse network of immune cells, known as diffuse NALT (D-NALT). In teleosts, only D-NALT is present and shares most of the canonical features of other teleost MALT. This review focuses on the evolution of NALT in vertebrates with an emphasis on the most recent findings in teleosts and lungfish. Whereas teleost are currently the most ancient group where NALT has been found, lungfish appear to be the earliest group to have evolved primitive O-NALT structures. PMID:26391349

  2. Expansion of transducin subunit gene families in early vertebrate tetraploidizations.

    PubMed

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

    2012-10-01

    Hundreds of gene families expanded in the early vertebrate tetraploidizations including many gene families in the phototransduction cascade. We have investigated the evolution of the heterotrimeric G-proteins of photoreceptors, the transducins, in relation to these events using both phylogenetic analyses and synteny comparisons. Three alpha subunit genes were identified in amniotes and the coelacanth, GNAT1-3; two of these were identified in amphibians and teleost fish, GNAT1 and GNAT2. Most tetrapods have four beta genes, GNB1-4, and teleosts have additional duplicates. Finally, three gamma genes were identified in mammals, GNGT1, GNG11 and GNGT2. Of these, GNGT1 and GNGT2 were found in the other vertebrates. In frog and zebrafish additional duplicates of GNGT2 were identified. Our analyses show all three transducin families expanded during the early vertebrate tetraploidizations and the beta and gamma families gained additional copies in the teleost-specific genome duplication. This suggests that the tetraploidizations contributed to visual specialisations. PMID:22814267

  3. Structural and functional evolution of vertebrate neuroendocrine stress systems.

    PubMed

    Denver, Robert John

    2009-04-01

    The vertebrate hypothalamus-pituitary-adrenal (HPA; or interrenal) axis plays pivotal roles in animal development and in physiological and behavioral adaptation to environmental change. The HPA, or stress axis, is organized in a hierarchical manner, with feedback operating at several points along the axis. Recent findings suggest that the proteins, gene structures, and signaling pathways of the HPA axis were present in the earliest vertebrates and have been maintained by natural selection owing to their critical adaptive roles. In all vertebrates studied, the HPA axis is activated in response to stressors and is controlled centrally by peptides of the corticotropin-releasing factor (CRF) family of which four paralogous members have been identified. Signaling by CRF-like peptides is mediated by at least two distinct G protein-coupled receptors and modulated by a secreted binding protein. These neuropeptides function as hypophysiotropins and as neurotransmitters/neuromodulators, influencing stress-related behaviors, such as anxiety and fear. In addition to modulating HPA activity and behavioral stress responses, CRF-like peptides are implicated in timing key life history transitions, such as metamorphosis in amphibians and birth in mammals. CRF-like peptides and signaling components are also expressed outside of the central nervous system where they have diverse physiological functions. Glucocorticoids are the downstream effectors of the HPA axis, playing essential roles in development, energy balance and behavior, and feedback actions on the activity of the HPA axis. PMID:19456324

  4. CRDB: database of chemosensory receptor gene families in vertebrate.

    PubMed

    Dong, Dong; Jin, Ke; 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

  5. 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.

  6. Recent findings on vertebrate developmental immunity using the zebrafish model.

    PubMed

    Galindo-Villegas, Jorge

    2016-01-01

    To grant survival against sterile or microbe induced inflammation, all animals rely on correct immune system functioning. The development of immunity occurs in vertebrates during embryogenesis in a process called hematopoiesis, which is characterized by the formation of blood cellular components such as embryonic erythrocytes and primitive macrophages. These cells are formed in a sterile environment from a rare subset of pluripotent hematopoietic stem cells (HSC) during a brief period of the primitive hematopoietic wave. Diverse signals, like Notch, are indispensable in HSC emergence and differentiation. However, to successfully replicate the process in vitro using pluripotent precursors, the full set of required signals is still a matter of debate. Among the latest findings, proinflammatory signals produced by transient primitive myelocites in zebrafish have been seen to act as essential mediators in establishing the HSC program of the adult vertebrate hematopoietic system. In this regard, the zebrafish immune model has emerged as a feasible live vertebrate model for examining developmental immunity and related host-microbe interactions, both at the molecular and cellular level. Thus, using the zebrafish embryo, this review summarizes recent findings, on the signals required for immune development and further maturation of the system, in a context where no adaptive immune response has yet been developed. PMID:26589453

  7. Purification of the Vertebrate Nuclear Pore Complex by Biochemical Criteria

    PubMed Central

    Miller, Brian R.; Forbes, Douglass J.

    2015-01-01

    The nuclear pore is a large and complex biological machine, mediating all signal-directed transport between the nucleus and the cytoplasm. The vertebrate pore has a mass of ~120 million daltons or 30 times the size of a ribosome. The large size of the pore, coupled to its tight integration in the nuclear lamina, has hampered the isolation of pore complexes from vertebrate sources. We have now developed a strategy for the purification of nuclear pores from in vitro assembled annulate lamellae (AL), a cytoplasmic mimic of the nuclear envelope that lacks a lamina, nuclear matrix, and chromatin-associated proteins. We find that purified pore complexes from annulate lamellae contain every nuclear pore protein tested. In addition, immunoblotting reveals the presence of soluble transport receptors and factors known to play important roles in the transport of macromolecules through the pore. While transport factors such as Ran and NTF2 show only transient interaction with the pores, a number of soluble transport receptors, including importin β, show a tight association with the purified pores. In summary, we report that we have purified the vertebrate pore by biochemical criteria; silver staining reveals ~40–50 distinct protein bands. PMID:11208084

  8. 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

  9. Evolutionary aspects of self- and world consciousness in vertebrates

    PubMed Central

    Fabbro, Franco; Aglioti, Salvatore M.; Bergamasco, Massimo; Clarici, Andrea; Panksepp, Jaak

    2015-01-01

    Although most aspects of world and self-consciousness are inherently subjective, neuroscience studies in humans and non-human animals provide correlational and causative indices of specific links between brain activity and representation of the self and the world. In this article we review neuroanatomic, neurophysiological and neuropsychological data supporting the hypothesis that different levels of self and world representation in vertebrates rely upon (i) a “basal” subcortical system that includes brainstem, hypothalamus and central thalamic nuclei and that may underpin the primary (or anoetic) consciousness likely present in all vertebrates; and (ii) a forebrain system that include the medial and lateral structures of the cerebral hemispheres and may sustain the most sophisticated forms of consciousness [e.g., noetic (knowledge based) and autonoetic, reflective knowledge]. We posit a mutual, bidirectional functional influence between these two major brain circuits. We conclude that basic aspects of consciousness like primary self and core self (based on anoetic and noetic consciousness) are present in many species of vertebrates and that, even self-consciousness (autonoetic consciousness) does not seem to be a prerogative of humans and of some non-human primates but may, to a certain extent, be present in some other mammals and birds PMID:25859205

  10. Reproductive costs in terrestrial male vertebrates: insights from bird studies.

    PubMed

    Bleu, Josefa; Gamelon, Marlène; Sæther, Bernt-Erik

    2016-01-27

    Reproduction requires resources that cannot be allocated to other functions resulting in direct reproductive costs (i.e. trade-offs between current reproduction and subsequent survival/reproduction). In wild vertebrates, direct reproductive costs have been widely described in females, but their occurrence in males remains to be explored. To fill this gap, we gathered 53 studies on 48 species testing direct reproductive costs in male vertebrates. We found a trade-off between current reproduction and subsequent performances in 29% of the species and in every clade. As 73% of the studied species are birds, we focused on that clade to investigate whether such trade-offs are associated with (i) levels of paternal care, (ii) polygyny or (iii) pace of life. More precisely for this third question, it is expected that fast species (i.e. short lifespan, early maturity, high fecundity) pay a cost in terms of survival, whereas slow species (with opposite characteristics) do so in terms of fecundity. Our findings tend to support this hypothesis. Finally, we pointed out the potential confounding effects that should be accounted for when investigating reproductive costs in males and strongly encourage the investigation of such costs in more clades to understand to what extent our results are relevant for other vertebrates. PMID:26791619

  11. Increased complexity of gene structure and base composition in vertebrates.

    PubMed

    Wu, Ying; Yuan, Huizhong; Tan, Shengjun; Chen, Jian-Qun; Tian, Dacheng; Yang, Haiwang

    2011-07-20

    How the structure and base composition of genes changed with the evolution of vertebrates remains a puzzling question. Here we analyzed 895 orthologous protein-coding genes in six multicellular animals: human, chicken, zebrafish, sea squirt, fruit fly, and worm. Our analyses reveal that many gene regions, particularly intron and 3' UTR, gradually expanded throughout the evolution of vertebrates from their invertebrate ancestors, and that the number of exons per gene increased. Studies based on all protein-coding genes in each genome provide consistent results. We also find that GC-content increased in many gene regions (especially 5' UTR) in the evolution of endotherms, except in coding-exons. Analysis of individual genomes shows that 3' UTR demonstrated stronger length and GC-content correlation with intron than 5' UTR, and gene with large intron in all six species demonstrated relatively similar GC-content. Our data indicates a great increase in complexity in vertebrate genes and we propose that the requirement for morphological and functional changes is probably the driving force behind the evolution of structure and base composition complexity in multicellular animal genes. PMID:21777854

  12. Reproductive costs in terrestrial male vertebrates: insights from bird studies

    PubMed Central

    Gamelon, Marlène; Sæther, Bernt-Erik

    2016-01-01

    Reproduction requires resources that cannot be allocated to other functions resulting in direct reproductive costs (i.e. trade-offs between current reproduction and subsequent survival/reproduction). In wild vertebrates, direct reproductive costs have been widely described in females, but their occurrence in males remains to be explored. To fill this gap, we gathered 53 studies on 48 species testing direct reproductive costs in male vertebrates. We found a trade-off between current reproduction and subsequent performances in 29% of the species and in every clade. As 73% of the studied species are birds, we focused on that clade to investigate whether such trade-offs are associated with (i) levels of paternal care, (ii) polygyny or (iii) pace of life. More precisely for this third question, it is expected that fast species (i.e. short lifespan, early maturity, high fecundity) pay a cost in terms of survival, whereas slow species (with opposite characteristics) do so in terms of fecundity. Our findings tend to support this hypothesis. Finally, we pointed out the potential confounding effects that should be accounted for when investigating reproductive costs in males and strongly encourage the investigation of such costs in more clades to understand to what extent our results are relevant for other vertebrates. PMID:26791619

  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. UntranslatedmRNAregions (UTRs) are key mediators of post-transcriptional regulation. Previous studies have predicted thousands ofORFs 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 andRNAlevels, with a similar magnitude to miRNAs. Reporter experiments reveal clear repression of downstream translation byuORFs/oORFs.uORFnumber, intercistronic distance, overlap with theCDS, and initiation context most strongly influence translation. Evolution has targeted these features to favoruORFs amenable to regulation over constitutively repressiveuORFs/oORFs. Finally, we observe that the regulatory potential ofuORFs on individual genes is conserved across species. These results provide insight into the regulatory code withinmRNAleader sequences and their capacity to modulate translation across vertebrates. PMID:26896445

  14. Progression of Infection after Surgical CT Navigation-Assisted Aspiration Biopsy of a Vertebral Abscess

    PubMed Central

    Spyropoulou, Vasiliki; Valaikaite, Raimunda; Dhouib, Amira; Dayer, Romain; Ceroni, Dimitri

    2016-01-01

    Background Context. Computed tomography- (CT-) guided fine-needle aspiration biopsy of the vertebral body is an important tool in the diagnostic evaluation of vertebral osteomyelitis. The procedure is considered simple to perform and it is considered a safe procedure with few complications. Purpose. The purpose of this study was to describe an unusual complication due to a CT-guided fine-needle aspiration biopsy of the vertebral body of L3, to better understand the relationship between surgical procedure and complication, and to reflect on how to avoid it. Study Design/Setting. Case report and literature review. Methods. The medical records, laboratory findings, and radiographic imaging studies of an 11-year-old boy, with an unusual complication due to a CT-guided fine-needle aspiration biopsy of the vertebral body of L3, were reviewed. Results. We report a case of vertebral osteomyelitis of L3 caused by methicillin-sensitive Staphylococcus aureus (MSSA). Following a computed tomography-guided aspiration biopsy of the vertebral body of L3, vertebral osteomyelitis rapidly progressed into the vertebral body of L4 as well as the L3-L4 disk. Conclusions. Based on the present case, one should consider that a CT-guided fine-needle aspiration biopsy of the vertebral body may be complicated by a progression of a vertebral osteomyelitis into both the intervertebral disk and also the adjacent vertebral body. PMID:26949558

  15. Progression of Infection after Surgical CT Navigation-Assisted Aspiration Biopsy of a Vertebral Abscess.

    PubMed

    Spyropoulou, Vasiliki; Valaikaite, Raimunda; Dhouib, Amira; Dayer, Romain; Ceroni, Dimitri

    2016-01-01

    Background Context. Computed tomography- (CT-) guided fine-needle aspiration biopsy of the vertebral body is an important tool in the diagnostic evaluation of vertebral osteomyelitis. The procedure is considered simple to perform and it is considered a safe procedure with few complications. Purpose. The purpose of this study was to describe an unusual complication due to a CT-guided fine-needle aspiration biopsy of the vertebral body of L3, to better understand the relationship between surgical procedure and complication, and to reflect on how to avoid it. Study Design/Setting. Case report and literature review. Methods. The medical records, laboratory findings, and radiographic imaging studies of an 11-year-old boy, with an unusual complication due to a CT-guided fine-needle aspiration biopsy of the vertebral body of L3, were reviewed. Results. We report a case of vertebral osteomyelitis of L3 caused by methicillin-sensitive Staphylococcus aureus (MSSA). Following a computed tomography-guided aspiration biopsy of the vertebral body of L3, vertebral osteomyelitis rapidly progressed into the vertebral body of L4 as well as the L3-L4 disk. Conclusions. Based on the present case, one should consider that a CT-guided fine-needle aspiration biopsy of the vertebral body may be complicated by a progression of a vertebral osteomyelitis into both the intervertebral disk and also the adjacent vertebral body. PMID:26949558

  16. Decelerated genome evolution in modern vertebrates revealed by analysis of multiple lancelet genomes.

    PubMed

    Huang, Shengfeng; Chen, Zelin; Yan, Xinyu; Yu, Ting; Huang, Guangrui; Yan, Qingyu; Pontarotti, Pierre Antoine; Zhao, Hongchen; Li, Jie; Yang, Ping; Wang, Ruihua; Li, Rui; Tao, Xin; Deng, Ting; Wang, Yiquan; Li, Guang; Zhang, Qiujin; Zhou, Sisi; You, Leiming; Yuan, Shaochun; Fu, Yonggui; Wu, Fenfang; Dong, Meiling; Chen, Shangwu; Xu, Anlong

    2014-01-01

    Vertebrates diverged from other chordates ~500 Myr ago and experienced successful innovations and adaptations, but the genomic basis underlying vertebrate origins are not fully understood. Here we suggest, through comparison with multiple lancelet (amphioxus) genomes, that ancient vertebrates experienced high rates of protein evolution, genome rearrangement and domain shuffling and that these rates greatly slowed down after the divergence of jawed and jawless vertebrates. Compared with lancelets, modern vertebrates retain, at least relatively, less protein diversity, fewer nucleotide polymorphisms, domain combinations and conserved non-coding elements (CNE). Modern vertebrates also lost substantial transposable element (TE) diversity, whereas lancelets preserve high TE diversity that includes even the long-sought RAG transposon. Lancelets also exhibit rapid gene turnover, pervasive transcription, fastest exon shuffling in metazoans and substantial TE methylation not observed in other invertebrates. These new lancelet genome sequences provide new insights into the chordate ancestral state and the vertebrate evolution. PMID:25523484

  17. Decelerated genome evolution in modern vertebrates revealed by analysis of multiple lancelet genomes

    PubMed Central

    Huang, Shengfeng; Chen, Zelin; Yan, Xinyu; Yu, Ting; Huang, Guangrui; Yan, Qingyu; Pontarotti, Pierre Antoine; Zhao, Hongchen; Li, Jie; Yang, Ping; Wang, Ruihua; Li, Rui; Tao, Xin; Deng, Ting; Wang, Yiquan; Li, Guang; Zhang, Qiujin; Zhou, Sisi; You, Leiming; Yuan, Shaochun; Fu, Yonggui; Wu, Fenfang; Dong, Meiling; Chen, Shangwu; Xu, Anlong

    2014-01-01

    Vertebrates diverged from other chordates ~500 Myr ago and experienced successful innovations and adaptations, but the genomic basis underlying vertebrate origins are not fully understood. Here we suggest, through comparison with multiple lancelet (amphioxus) genomes, that ancient vertebrates experienced high rates of protein evolution, genome rearrangement and domain shuffling and that these rates greatly slowed down after the divergence of jawed and jawless vertebrates. Compared with lancelets, modern vertebrates retain, at least relatively, less protein diversity, fewer nucleotide polymorphisms, domain combinations and conserved non-coding elements (CNE). Modern vertebrates also lost substantial transposable element (TE) diversity, whereas lancelets preserve high TE diversity that includes even the long-sought RAG transposon. Lancelets also exhibit rapid gene turnover, pervasive transcription, fastest exon shuffling in metazoans and substantial TE methylation not observed in other invertebrates. These new lancelet genome sequences provide new insights into the chordate ancestral state and the vertebrate evolution. PMID:25523484

  18. 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

  19. Evolutionary hierarchy of vertebrate-like heterotrimeric G protein families.

    PubMed

    Krishnan, Arunkumar; Mustafa, Arshi; Almén, Markus Sällman; Fredriksson, Robert; Williams, Michael J; Schiöth, Helgi B

    2015-10-01

    Heterotrimeric G proteins perform a crucial role as molecular switches controlling various cellular responses mediated by G protein-coupled receptor (GPCR) signaling pathway. Recent data have shown that the vertebrate-like G protein families are found across metazoans and their closest unicellular relatives. However, an overall evolutionary hierarchy of vertebrate-like G proteins, including gene family annotations and in particular mapping individual gene gain/loss events across diverse holozoan lineages is still incomplete. Here, with more expanded invertebrate taxon sampling, we have reconstructed phylogenetic trees for each of the G protein classes/families and provide a robust classification and hierarchy of vertebrate-like heterotrimeric G proteins. Our results further extend the evidence that the common ancestor (CA) of holozoans had at least five ancestral Gα genes corresponding to all major vertebrate Gα classes and contain a total of eight genes including two Gβ and one Gγ. Our results also indicate that the GNAI/O-like gene likely duplicated in the last CA of metazoans to give rise to GNAI- and GNAO-like genes, which are conserved across invertebrates. Moreover, homologs of GNB1-4 paralogon- and GNB5 family-like genes are found in most metazoans and that the unicellular holozoans encode two ancestral Gβ genes. Similarly, most bilaterian invertebrates encode two Gγ genes which include a representative of the GNG gene cluster and a putative homolog of GNG13. Interestingly, our results also revealed key evolutionary events such as the Drosophila melanogaster eye specific Gβ subunit that is found conserved in most arthropods and several previously unidentified species specific expansions within Gαi/o, Gαs, Gαq, Gα12/13 classes and the GNB1-4 paralogon. Also, we provide an overall proposed evolutionary scenario on the expansions of all G protein families in vertebrate tetraploidizations. Our robust classification/hierarchy is essential to further

  20. 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

  1. Indication for Partial Vertebral Osteotomy and Realignment in Posterior Spinal Fixation for Osteoporotic Thoracolumbar Vertebral Collapse with Neurological Deficits.

    PubMed

    Takahashi, Toshiyuki; Hanakita, Junya; Kawaoka, Taigo; Ohtake, Yasufumi; Adachi, Hiromasa; Shimizu, Kampei

    2016-08-15

    Instrumented spinal fixation is ordinarily required in patients who present with myelopathy or cauda equina syndrome secondary to vertebral collapse following osteoporotic thoracolumbar fracture. Posterior spinal fixation is a major surgical option, and partial vertebral osteotomy (PVO) through a posterior approach is occasionally reasonable for achievement of complete neural decompression and improvement of excessive local kyphosis. However, the indications and need for PVO remain unclear. The objectives of this retrospective study were to determine the efficacy and safety of posterior spinal fixation with or without PVO for osteoporotic thoracolumbar vertebral collapse and identify patients who require neural decompression and alignment correction by PVO. We retrospectively reviewed the clinical records of 20 patients (13 females, 7 males; mean age, 67.1 years) who underwent instrumented posterior fixation for osteoporotic thoracolumbar vertebral fracture. Clinical outcomes were assessed by the Japanese Orthopedic Association score and visual analog scale scores in the lumbar and leg areas. PVO was added with posterior spinal fixation in eight patients because neural decompression was incomplete after laminectomy as indicated by intraoperative echo imaging. Neurological and functional recovery significantly improved during follow-up. Clinical outcomes in patients who underwent PVO were similar to those in patients who did not undergo PVO. However, correction of the local kyphotic angle and improvement of spinal canal compromise after surgery was significant in patients who underwent PVO. The patients who required PVO had a less local kyphotic angle in the supine position and higher occupation rate of the fractured fragment in the spinal canal in the preoperative examination. PMID:27021642

  2. Indication for Partial Vertebral Osteotomy and Realignment in Posterior Spinal Fixation for Osteoporotic Thoracolumbar Vertebral Collapse with Neurological Deficits

    PubMed Central

    TAKAHASHI, Toshiyuki; HANAKITA, Junya; KAWAOKA, Taigo; OHTAKE, Yasufumi; ADACHI, Hiromasa; SHIMIZU, Kampei

    2016-01-01

    Instrumented spinal fixation is ordinarily required in patients who present with myelopathy or cauda equina syndrome secondary to vertebral collapse following osteoporotic thoracolumbar fracture. Posterior spinal fixation is a major surgical option, and partial vertebral osteotomy (PVO) through a posterior approach is occasionally reasonable for achievement of complete neural decompression and improvement of excessive local kyphosis. However, the indications and need for PVO remain unclear. The objectives of this retrospective study were to determine the efficacy and safety of posterior spinal fixation with or without PVO for osteoporotic thoracolumbar vertebral collapse and identify patients who require neural decompression and alignment correction by PVO. We retrospectively reviewed the clinical records of 20 patients (13 females, 7 males; mean age, 67.1 years) who underwent instrumented posterior fixation for osteoporotic thoracolumbar vertebral fracture. Clinical outcomes were assessed by the Japanese Orthopedic Association score and visual analog scale scores in the lumbar and leg areas. PVO was added with posterior spinal fixation in eight patients because neural decompression was incomplete after laminectomy as indicated by intraoperative echo imaging. Neurological and functional recovery significantly improved during follow-up. Clinical outcomes in patients who underwent PVO were similar to those in patients who did not undergo PVO. However, correction of the local kyphotic angle and improvement of spinal canal compromise after surgery was significant in patients who underwent PVO. The patients who required PVO had a less local kyphotic angle in the supine position and higher occupation rate of the fractured fragment in the spinal canal in the preoperative examination. PMID:27021642

  3. Comparative sensitivity of aquatic invertebrate and vertebrate species to wastewater from an operational coal mine in central Queensland, Australia.

    PubMed

    Lanctôt, C; Wilson, S P; Fabbro, L; Leusch, F D L; Melvin, S D

    2016-07-01

    Coal excavation and refinement processes generate substantial volumes of contaminated effluent that may be detrimental to aquatic ecosystems. As such, understanding the impacts of coal mine water releases on aquatic animals and ecosystems is essential for effectively managing and protecting neighboring environments. Such information will ultimately be applied towards developing ongoing monitoring strategies that are protective of native wildlife. Despite intensive mining operations in Australia, few studies have documented toxicity associated with coal mine wastewater (CMW) on native species. To address existing knowledge gaps, we investigated acute toxicity (48-96h) using eight native invertebrate species and sub-chronic effects (2 week) using three vertebrate species following exposure to wastewater from two dams (CMW1 and CMW2) located at an open-cut coal mine licensed to discharge into the Fitzroy catchment (Queensland, Australia). Wastewater from these sites is characterized by elevated conductivity, pH, sulfates as well as relatively high total and dissolved metal(loid)s (including As, Al, B, Cu, Mn, Ni, Se and Zn). Acute exposures revealed cladocerans (Daphnia carinata) and planarians (Dugesia sp.) to be the most sensitive species, exhibiting significant mortality after 48 and 96h exposure to CMW2, respectively. Neither wastewater was found to elicit acute toxicity in vertebrates, but a range of sub-lethal morphological effects were observed following the sub-chronic exposures. The overall response pattern was characterized by decreased condition factor and hepatosomatic index in the fish Hypseleotris compressa and Pseudomugil signifier, and in Limnodynastes peronii tadpoles. Tadpoles were generally more sensitive compared to the two fish species. Differences in responses were observed amongst CMW1 and CMW2, which likely relates to differences in physico-chemical properties between sites. Our results have identified several candidate vertebrate and

  4. Sun protection

    MedlinePlus

    ... age spots are caused by exposure to the sun. The two types of sun rays that can injure the skin are ultraviolet ... changes is to protect your skin from the sun. This includes using sunscreen and other protective measures. ...

  5. 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

  6. Ecological Relationships of Meso-Scale Distribution in 25 Neotropical Vertebrate Species

    PubMed Central

    Michalski, Lincoln José; Norris, Darren; de Oliveira, Tadeu Gomes; Michalski, Fernanda

    2015-01-01

    Vertebrates are a vital ecological component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services they continue to be threatened by anthropogenic impacts throughout the Amazon. Here we use a standardized, regularly spaced arrangement of camera traps within 25km2 to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. We examined seasonal differences in the per species encounter rates (number of photos per camera trap and number of cameras with photos). Generalized linear models (GLMs) were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river) on the number of photos per species and on functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (Panthera onca) and Puma (Puma concolor)] and their prey. A total of 649 independent photos of 25 species were obtained from 1,800 camera trap days (900 each during wet and dry seasons). Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons for only three species (Mazama americana, Dasyprocta leporina and Myoprocta acouchy) all of which were photographed more (3 to 10 fold increase) during the wet season. Mazama americana was the only species where a significant difference was found in occupancy, with more photos in more cameras during the wet season. For most groups and species variation in the number of photos per camera was only explained weakly by the GLMs (deviance explained ranging from 10.3 to 54.4%). Terrestrial birds (Crax alector, Psophia crepitans and Tinamus major) and rodents (Cuniculus paca, Dasyprocta leporina and M. acouchy) were the notable exceptions, with our GLMs significantly explaining variation in the distribution of all species

  7. Sudden cerebral infarction after interventional vertebral artery embolism for vertebral artery injury during removal of C1-C2 pedicle screw fixation: a case report

    PubMed Central

    Yang, Yi; Liu, Hao; Ma, Litai; Zeng, Jiancheng; Song, Yueming; Xie, Xiaodong

    2015-01-01

    Vertebral artery injury (VAI) is a rare but serious complication of cervical spine surgery. Instrumented posterior surgery of the upper cervical spine places the vertebral artery at the highest risk of injury. However, VAI during removal of cervical internal fixation is really rare and unexpected. We present a case of 52-year-old male patient who suffered VAI during removal of C1-C2 pedicle screw fixation. An interventional vertebral artery embolism was performed and the patient suffered a sudden cerebral infarction one day after interventional vertebral artery embolism. From this case, removal of upper cervical pedicle screws of malposition is not recommended if it is not really necessary for some other reasons. Interventional vertebral artery embolism is an effective and less invasive procedure than open ligation surgery in the treatment of haemorrhage resulted from VAI but potential risk of cerebral infarction should not be ignored. PMID:26629224

  8. The effects of lifestyle, dietary dairy intake and diabetes on bone density and vertebral deformity prevalence: the EVOS study.

    PubMed

    Lunt, M; Masaryk, P; Scheidt-Nave, C; Nijs, J; Poor, G; Pols, H; Falch, J A; Hammermeister, G; Reid, D M; Benevolenskaya, L; Weber, K; Cannata, J; O'Neill, T W; Felsenberg, D; Silman, A J; Reeve, J

    2001-01-01

    The risk of low and moderate energy fracture is related to bone mineral density (BMD). Yet it is uncertain whether the epidemiologic determinants of fracture risk are the same as for low bone density. The European Vertebral Osteoporosis Study was a population-based prevalence study of vertebral deformity in 36 age-stratified population samples aged 50-80 years. In nearly 4000 subjects (13 centers), BMD measurements were also made at the spine, femoral neck and femoral trochanter. To investigate whether effects of reported physical activity on spine deformity risk were mediated through BMD, we modeled these and other risk factor data with BMD as the dependent variate after adjusting for age, center, sex and body mass index (BMI). The significant determinants of vertebral deformity risk were also entered into logistic models of deformity risk that included BMD measurements as covariates. Both current and lifetime physical activity were positively associated with BMD. This effect was stronger with hip BMD than with spine BMD. Lifetime smoking exposure was associated with reduced BMD. Type 2 diabetes mellitus was associated with increased BMD. Weak positive associations were found between consumption of dairy products and BMD at the three measured sites and these were strengthened by an interaction with measures of physical activity in men. Physical activity in women had the largest beneficial effect in lean women and in women exposed to hormone replacement therapy. When fracture risk was modeled with BMD as a covariate, the lifestyle and dietary determinants became less strongly related to vertebral deformity risk, suggesting that BMD may have acted as an intermediary variable. However, heavy physical activity in men still increased spine deformity risk after adjusting for BMD. It is concluded that physical activity in both genders and milk consumption in young women might protect against vertebral deformities in later life through their effects on bone density. The

  9. Molecular evidence from Ciona intestinalis for the evolutionary origin of vertebrate sensory placodes.

    PubMed

    Mazet, Françoise; Hutt, James A; Milloz, Josselin; Millard, John; Graham, Anthony; Shimeld, Sebastian M

    2005-06-15

    Cranial sensory placodes are focused areas of the head ectoderm of vertebrates that contribute to the development of the cranial sense organs and their associated ganglia. Placodes have long been considered a key character of vertebrates, and their evolution is proposed to have been essential for the evolution of an active predatory lifestyle by early vertebrates. Despite their importance for understanding vertebrate origins, the evolutionary origin of placodes has remained obscure. Here, we use a panel of molecular markers from the Six, Eya, Pax, Dach, FoxI, COE and POUIV gene families to examine the tunicate Ciona intestinalis for evidence of structures homologous to vertebrate placodes. Our results identify two domains of Ciona ectoderm that are marked by the genetic cascade that regulates vertebrate placode formation. The first is just anterior to the brain, and we suggest this territory is equivalent to the olfactory/adenohypophyseal placodes of vertebrates. The second is a bilateral domain adjacent to the posterior brain and includes cells fated to form the atrium and atrial siphon of adult Ciona. We show this bares most similarity to placodes fated to form the vertebrate acoustico-lateralis system. We interpret these data as support for the hypothesis that sensory placodes did not arise de novo in vertebrates, but evolved from pre-existing specialised areas of ectoderm that contributed to sensory organs in the common ancestor of vertebrates and tunicates. PMID:15950613

  10. Segmentation of vertebral bodies in CT and MR images based on 3D deterministic models

    NASA Astrophysics Data System (ADS)

    Štern, Darko; Vrtovec, Tomaž; Pernuš, Franjo; Likar, Boštjan

    2011-03-01

    The evaluation of vertebral deformations is of great importance in clinical diagnostics and therapy of pathological conditions affecting the spine. Although modern clinical practice is oriented towards the computed tomography (CT) and magnetic resonance (MR) imaging techniques, as they can provide a detailed 3D representation of vertebrae, the established methods for the evaluation of vertebral deformations still provide only a two-dimensional (2D) geometrical description. Segmentation of vertebrae in 3D may therefore not only improve their visualization, but also provide reliable and accurate 3D measurements of vertebral deformations. In this paper we propose a method for 3D segmentation of individual vertebral bodies that can be performed in CT and MR images. Initialized with a single point inside the vertebral body, the segmentation is performed by optimizing the parameters of a 3D deterministic model of the vertebral body to achieve the best match of the model to the vertebral body in the image. The performance of the proposed method was evaluated on five CT (40 vertebrae) and five T2-weighted MR (40 vertebrae) spine images, among them five are normal and five are pathological. The results show that the proposed method can be used for 3D segmentation of vertebral bodies in CT and MR images and that the proposed model can describe a variety of vertebral body shapes. The method may be therefore used for initializing whole vertebra segmentation or reliably describing vertebral body deformations.

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

    USGS Publications Warehouse

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

    2016-01-01

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

  12. A review of anatomical and mechanical factors affecting vertebral body integrity

    PubMed Central

    2004-01-01

    Background: The aetiology of osteoporotic vertebral fracture is multifactorial and may be conceptualised using a systems framework. Previous studies have established several correlates of vertebral fracture including reduced vertebral cross-sectional area, weakness in back extensor muscles, reduced bone mineral density, increasing age, worsening kyphosis and recent vertebral fracture. Alterations in these physical characteristics may influence biomechanical loads and neuromuscular control of the trunk and contribute to changes in subregional bone mineral density of the vertebral bodies. Methods: This review discusses factors that have received less attention in the literature, which may contribute to the development of vertebral fracture. A literature review was conducted using electronic databases including Medline, Cinahl and ISI Web of Science to examine the potential contribution of trabecular architecture, subregional bone mineral density, vertebral geometry, muscle force, muscle strength, neuromuscular control and intervertebral disc integrity to the aetiology of osteoporotic vertebral fracture. Interpretation: A better understanding of factors such as biomechanical loading and neuromuscular control of the trunk may help to explain the high incidence of subsequent vertebral fracture after sustaining an initial vertebral fracture. Consideration of these issues may be important in the development of prevention and management strategies. PMID:15912196

  13. Vascular Plant and Vertebrate Inventory of Chiricahua National Monument

    USGS Publications Warehouse

    Powell, Brian F.; Schmidt, Cecilia A.; Halvorson, William L.; Anning, Pamela

    2009-01-01

    This report summarizes the results of the first comprehensive inventory of vascular plants and vertebrates at Chiricahua National Monument (NM) in Arizona. This project was part of a larger effort to inventory vascular plants and vertebrates in eight National Park Service units in the Sonoran Desert Network of parks in Arizona and New Mexico. In 2002, 2003, and 2004 we surveyed for plants and vertebrates (amphibians, reptiles, birds, and mammals) at Chiricahua NM to document the presence of species within the boundaries of the monument. Because we used repeatable study designs and standardized field methods, these inventories can serve as the first step in a biological monitoring program for the monument. This report is also the first summary of previous research from the monument and therefore it provides an important overview of survey efforts to date. We used data from our inventory and previous research to compile complete species lists for the monument and to assess inventory completeness. We recorded a total of 424 species, including 37 not previously found at the monument (Table 1). We found 10 species of non-native plants and one non-native mammal. Most non-native plants were found along the western boundary of the monument. Based on a review of our inventory and past research at the monument, there have been a total of 1,137 species of plants and vertebrates found at the monument. We believe the inventories of vascular plants and vertebrates are nearly complete and that the monument has one of the most complete inventories of any unit in the Sonoran Desert Network. The mammal community at the monument had the highest species richness (69 species) and the amphibian and reptile community was among the lowest species richness (33 species) of any park in the Sonoran Desert Network. Species richness of the plant and bird communities was intermediate. Among the important determinants of species richness for all groups is the geographic location of the monument

  14. Vertebral classification using localized pathology-related shape model

    NASA Astrophysics Data System (ADS)

    Zewail, R.; Elsafi, A.; Durdle, N.

    2008-03-01

    Radiographs of the spine are frequently examined for assessment of vertebral abnormalities. Features like osteophytes (bony growth of vertebra's corners), and disc space narrowing are often used as visual evidence of osteoarthris or degenerative joint disease. These symptoms result in remarkable changes in the shapes of the vertebral body. Statistical analysis of anatomical structure has recently gained increased popularity within the medical imaging community, since they have the potential to enhance the automated diagnosis process. In this paper, we present a novel method for computer-assisted vertebral classification using a localized, pathology-related shape model. The new classification scheme is able to assess the condition of multiple vertebrae simultaneously, hence is possible to directly classify the whole spine anatomy according to the condition of interest (anterior osteophites). At the core of this method is a new localized shape model that uses concepts of sparsity, dimension reduction, and statistical independence to extract sets of localized modes of deformations specific to each of the vertebrae under investigation. By projection of the shapes onto any specific set of deformation modes (or basis), we obtain low-dimensional features that are most directly related to the pathology of the vertebra of interest. These features are then used as input to a support vector machine classifier to classify the vertebra under investigation as normal or upnormal. Experiments are conducted using contours from digital x-ray images of five vertebrae of lumbar spine. The accuracy of the classification scheme is assessed using the ROC curves. An average specifity of 96.8 % is achieved with a sensitivity of 80 %.

  15. Deep Vertebrate Roots for Mammalian Zinc Finger Transcription Factor Subfamilies

    PubMed Central

    Liu, Hui; Chang, Li-Hsin; Sun, Younguk; Lu, Xiaochen; Stubbs, Lisa

    2014-01-01

    While many vertebrate transcription factor (TF) families are conserved, the C2H2 zinc finger (ZNF) family stands out as a notable exception. In particular, novel ZNF gene types have arisen, duplicated, and diverged independently throughout evolution to yield many lineage-specific TF genes. This evolutionary dynamic not only raises many intriguing questions but also severely complicates identification of those ZNF genes that remain functionally conserved. To address this problem, we searched for vertebrate “DNA binding orthologs” by mining ZNF loci from eight sequenced genomes and then aligning the patterns of DNA-binding amino acids, or “fingerprints,” extracted from the encoded ZNF motifs. Using this approach, we found hundreds of lineage-specific genes in each species and also hundreds of orthologous groups. Most groups of orthologs displayed some degree of fingerprint divergence between species, but 174 groups showed fingerprint patterns that have been very rigidly conserved. Focusing on the dynamic KRAB-ZNF subfamily—including nearly 400 human genes thought to possess potent KRAB-mediated epigenetic silencing activities—we found only three genes conserved between mammals and nonmammalian groups. These three genes, members of an ancient familial cluster, encode an unusual KRAB domain that functions as a transcriptional activator. Evolutionary analysis confirms the ancient provenance of this activating KRAB and reveals the independent expansion of KRAB-ZNFs in every vertebrate lineage. Most human ZNF genes, from the most deeply conserved to the primate-specific genes, are highly expressed in immune and reproductive tissues, indicating that they have been enlisted to regulate evolutionarily divergent biological traits. PMID:24534434

  16. 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

  17. Phylogenetic analysis of vertebrate lactate dehydrogenase (LDH) multigene families.

    PubMed

    Li, Yi-Ju; Tsoi, Stephen C-M; Mannen, Hideyuka; Shoei-lung Li, Steven

    2002-05-01

    In this paper we analyzed 49 lactate dehydrogenase (LDH) sequences, mostly from vertebrates. The amino acid sequence differences were found to be larger for a human-killifish pair than a human-lamprey pair. This indicates that some protein sequence convergence may occur and reduce the sequence differences in distantly related species. We also examined transitions and transversions separately for several species pairs and found that the transitions tend to be saturated in the distantly related species pair, while transversions are increasing. We conclude that transversions maintain a conservative rate through the evolutionary time. Kimura's two-parameter model for multiple-hit correction on transversions only was used to derive a distance measure and then construct a neighbor-joining (NJ) tree. Three findings were revealed from the NJ tree: (i) the branching order of the tree is consistent with the common branch pattern of major vertebrates; (ii) Ldh-A and Ldh-B genes were duplicated near the origin of vertebrates; and (iii) Ldh-C and Ldh-A in mammals were produced by an independent gene duplication in early mammalian history. Furthermore, a relative rate test showed that mammalian Ldh-C evolved more rapidly than mammalian Ldh-A. Under a two-rate model, this duplication event was calibrated to be approximately 247 million years ago (mya), dating back to the Triassic period. Other gene duplication events were also discovered in Xenopus, the first duplication occurring approximately 60-70 mya in both Ldh-A and Ldh-B, followed by another recent gene duplication event, approximately 20 mya, in Ldh-B. PMID:11965434

  18. The evolution of isochore patterns in vertebrate genomes

    PubMed Central

    Costantini, Maria; Cammarano, Rosalia; Bernardi, Giorgio

    2009-01-01

    Background Previous work from our laboratory showed that (i) vertebrate genomes are mosaics of isochores, typically megabase-size DNA segments that are fairly homogeneous in base composition; (ii) isochores belong to a small number of families (five in the human genome) characterized by different GC levels; (iii) isochore family patterns are different in fishes/amphibians and mammals/birds, the latter showing GC-rich isochore families that are absent or very scarce in the former; (iv) there are two modes of genome evolution, a conservative one in which isochore patterns basically do not change (e.g., among mammalian orders), and a transitional one, in which they do change (e.g., between amphibians and mammals); and (v) isochores are tightly linked to a number of basic biological properties, such as gene density, gene expression, replication timing and recombination. Results The present availability of a number of fully sequenced genomes ranging from fishes to mammals allowed us to carry out investigations that (i) more precisely quantified our previous conclusions; (ii) showed that the different isochore families of vertebrate genomes are largely conserved in GC levels and dinucleotide frequencies, as well as in isochore size; and (iii) isochore family patterns can be either conserved or change within both warm- and cold-blooded vertebrates. Conclusion On the basis of the results presented, we propose that (i) the large conservation of GC levels and dinucleotide frequencies may reflect the conservation of chromatin structures; (ii) the conservation of isochore size may be linked to the role played by isochores in chromosome structure and replication; (iii) the formation, the maintainance and the changes of isochore patterns are due to natural selection. PMID:19344507

  19. 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. PMID:26637127

  20. 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

  1. Threats from climate change to terrestrial vertebrate hotspots in Europe.

    PubMed

    Maiorano, Luigi; Amori, Giovanni; Capula, Massimo; Falcucci, Alessandra; Masi, Monica; Montemaggiori, Alessandro; Pottier, Julien; Psomas, Achilleas; Rondinini, Carlo; Russo, Danilo; Zimmermann, Niklaus E; Boitani, Luigi; Guisan, Antoine

    2013-01-01

    We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21(st) century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran's I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation. PMID:24066162

  2. Threats from Climate Change to Terrestrial Vertebrate Hotspots in Europe

    PubMed Central

    Maiorano, Luigi; Amori, Giovanni; Capula, Massimo; Falcucci, Alessandra; Masi, Monica; Montemaggiori, Alessandro; Pottier, Julien; Psomas, Achilleas; Rondinini, Carlo; Russo, Danilo; Zimmermann, Niklaus E.

    2013-01-01

    We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21st century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran’s I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation. PMID:24066162

  3. Physiological properties of vertebrate nerve cells in tissue culture.

    PubMed

    Dichter, M A

    1975-01-01

    Vertebrate neurons in tissue culture are providing us with a new model system for studying the complex events which occur during neuronal differentiation, synaptogenesis, and neural network formation. It is already apparent that dissociated embryo neurons are capable of differentiating both morphologically and physiologically along predetermined lines in the absence of external influences. These neurons can form new connections with one another but retain some specificity in their selections. Both simple and complex neural networks can be seen. At the present time, the development of the invitro model system is just being explored. The potential value of a system of this kind at a variety of investigative levels should be appreciated. Questions of a fundamental nature in neurobiology, such as how synapses form, what rules govern such interaction, how cells recognize one another, and the nature of the basic two-, three-, or four-cell circuits that comprise the more complex neurons tissue can be approached with this system. Studies of the neurons and synapses themselves can lead to a more basic understanding of vertebrate nervous system functioning. The development of certain pathophysiological processes and the effects of neuroactive drugs on vertebrate neurons may be studied at the cellular level. Finally, the basic mechanism of some genetic abnormalities which produce abnormal nervous structure and function may be more easily determined in a simplified in vitro model than in the intact central nervous system. The value of any model is not inherent in the elegance of the model itseld, but only in its ability to suggest answers to fundamental questions about the system being modeled. Many fundamental questions about brain mechanisms in mental retardation remain unanswered. Perhaps some day the model of nerve cells in tissue culture will bring us closer to the answers to these questions. PMID:173059

  4. Basal jawed vertebrate phylogenomics using transcriptomic data from Solexa sequencing.

    PubMed

    Chen, Ming; Zou, Ming; Yang, Lei; He, Shunping

    2012-01-01

    The traditionally accepted relationships among basal jawed vertebrates have been challenged by some molecular phylogenetic analyses based on mitochondrial sequences. Those studies split extant gnathostomes into two monophyletic groups: tetrapods and piscine branch, including Chondrichthyes, Actinopterygii and sarcopterygian fishes. Lungfish and bichir are found in a basal position on the piscine branch. Based on transcriptomes of an armored bichir (Polypterus delhezi) and an African lungfish (Protopterus sp.) we generated, expressed sequences and whole genome sequences available from public databases, we obtained 111 genes to reconstruct the phylogenetic tree of basal jawed vertebrates and estimated their times of divergence. Our phylogenomic study supports the traditional relationship. We found that gnathostomes are divided into Chondrichthyes and the Osteichthyes, both with 100% support values (posterior probabilities and bootstrap values). Chimaeras were found to have a basal position among cartilaginous fishes with a 100% support value. Osteichthyes were divided into Actinopterygii and Sarcopterygii with 100% support value. Lungfish and tetrapods form a monophyletic group with 100% posterior probability. Bichir and two teleost species form a monophyletic group with 100% support value. The previous tree, based on mitochondrial data, was significantly rejected by an approximately unbiased test (AU test, p = 0). The time of divergence between lungfish and tetrapods was estimated to be 391.8 Ma and the divergence of bichir from pufferfish and medaka was estimated to be 330.6 Ma. These estimates closely match the fossil record. In conclusion, our phylogenomic study successfully resolved the relationship of basal jawed vertebrates based on transtriptomes, EST and whole genome sequences. PMID:22558409

  5. 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. PMID:25426636

  6. The Primary Cilium: A Signaling Center During Vertebrate Development

    PubMed Central

    Goetz, Sarah C.

    2011-01-01

    The primary cilium has recently stepped into the spotlight, as a flood of data demonstrate that this organelle has crucial roles in vertebrate development and human genetic diseases. Cilia are required for the response to developmental signals, and evidence is accumulating that the primary cilium is specialized for Hedgehog (Hh) signal transduction. Formation of cilia, in turn, is regulated by other signaling pathways, possibly including the planar cell polarity pathway. The cilium therefore represents a nexus for signaling pathways during development. The connections between cilia and developmental signaling have begun to clarify the basis of human diseases associated with ciliary dysfunction. PMID:20395968

  7. Adult vertebrate behavioural aquatic toxicology: Reliability and validity.

    PubMed

    Parker, Matthew O

    2016-01-01

    Current advances in the ability to assay adult aquatic vertebrate behaviour are potentially very useful to aquatic toxicologists wishing to characterise the effects of pollutants on behaviour, cognition or neurodevelopment. This review considers two specific challenges faced by researchers wishing to exploit these technologies: maximising reliability and validity. It will suggest two behavioural procedures, with the potential for automation and high-throughput implementation, which can be used to measure social cohesion and anxiety, two areas of interest in behavioural aquatic toxicology. In addition, the review will make recommendations about how these procedures (and others) could be carried out to maximise reliability and validity. PMID:26358137

  8. Neural maps in insect versus vertebrate auditory systems.

    PubMed

    Hildebrandt, K Jannis

    2014-02-01

    The convergent evolution of hearing in insects and vertebrates raises the question about similarity of the central representation of sound in these distant animal groups. Topographic representations of spectral, spatial and temporal cues have been widely described in mammals, but evidence for such maps is scarce in insects. Recent data on insect sound encoding provides evidence for an early integration of sound parameters to form highly-specific representation that predict behavioral output. In mammals, new studies investigating neural representation of perceptual features in behaving animals allow asking similar questions. A comparative approach may help in understanding principles underlying the formation of perceptual categories and behavioral plasticity. PMID:24492083

  9. In vitro synthesis of vertebrate U1 snRNA.

    PubMed Central

    Lund, E; Dahlberg, J E

    1989-01-01

    We have developed a DNA-dependent in vitro transcription system for vertebrate snRNA genes. By isolating the nuclei (germinal vesicles, GVs) of Xenopus laevis oocytes under oil to maintain the in vivo composition of their internal milieu, we are able to prepare nuclei that retain their ability to synthesize snRNAs efficiently. Homogenates of these GVs synthesize correctly initiated and terminated U1 snRNA using exogenous X.laevis U1 genes as templates. The templates may be either injected into the nucleus prior to its isolation or added to the nuclear homogenate. Images PMID:2714253

  10. [Venomous and poisonous animals. IV. Envenomations by venomous aquatic vertebrates].

    PubMed

    Bédry, R; De Haro, L

    2007-04-01

    Epidemiological information on marine envenomation is generally less extensive in Europe than in tropical regions where these injuries are more severe and the need for medical advice is more frequent. For these reasons use of regional Poison Control Centers in the area where the injury occurs must be encouraged. The purpose of this review is to describe envenomation by bony fish (lion fish, stone fish, and catfish), cartilaginous fish (stingrays and poisonous sharks), or other venomous aquatic vertebrates (moray-eels and marine snakes). Understanding of these envenomation syndromes is important not only in tropical areas but also in Europe where importation of dangerous species has increased in recent years. PMID:17691425

  11. Termites, vertebrate herbivores, and the fruiting success of Acacia drepanolobium.

    PubMed

    Brody, Alison K; Palmer, Todd M; Fox-Dobbs, Kena; Doak, Dan F

    2010-02-01

    In African savannas, vertebrate herbivores are often identified as key determinants of plant growth, survivorship, and reproduction. However, plant reproduction is likely to be the product of responses to a suite of abiotic and biotic factors, including nutrient availability and interactions with antagonists and mutualists. In a relatively simple system, we examined the role of termites (which act as ecosystem engineers--modifying physical habitat and creating islands of high soil fertility), vertebrate herbivores, and symbiotic ants, on the fruiting success of a dominant plant, Acacia drepanolobium, in East African savannas. Using observational data, large-scale experimental manipulations, and analysis of foliar N, we found that Acacia drepanolobium trees growing at the edge of termite mounds were more likely to reproduce than those growing farther away, in off-mound soils. Although vertebrate herbivores preferentially used termite mounds as demonstrated by dung deposits, long-term exclusion of mammalian grazers did not significantly reduce A. drepanolobium fruit production. Leaf N was significantly greater in trees growing next to mounds than in those growing farther away, and this pattern was unaffected by exclusion of vertebrates. Thus, soil enrichment by termites, rather than through dung and urine deposition by large herbivores, is of primary importance to fruit production near mounds. Across all mound-herbivore treatment combinations, trees that harbored Crematogaster sjostedti were more likely to fruit than those that harbored one of the other three ant species. Although C. sjostedti is less aggressive than the other ants, it tends to inhabit large, old trees near termite mounds which are more likely to fruit than smaller ones. Termites play a key role in generating patches of nutrient-rich habitat important to the reproductive success of A. drepanolobium in East African savannas. Enhanced nutrient acquisition from termite mounds appears to allow plants to

  12. Post-Translational Modifications of Histones in Vertebrate Neurogenesis

    PubMed Central

    Mitrousis, Nikolaos; Tropepe, Vincent; Hermanson, Ola

    2015-01-01

    The process of neurogenesis, through which the entire nervous system of an organism is formed, has attracted immense scientific attention for decades. How can a single neural stem cell give rise to astrocytes, oligodendrocytes, and neurons? Furthermore, how is a neuron led to choose between the hundreds of different neuronal subtypes that the vertebrate CNS contains? Traditionally, niche signals and transcription factors have been on the spotlight. Recent research is increasingly demonstrating that the answer may partially lie in epigenetic regulation of gene expression. In this article, we comprehensively review the role of post-translational histone modifications in neurogenesis in both the embryonic and adult CNS. PMID:26733796

  13. Imaging vertebrate digestive function and lipid metabolism in vivo

    PubMed Central

    Otis, Jessica P.; Farber, Steven A.

    2012-01-01

    Challenges in imaging lipid-processing events in live, intact vertebrate models have historically led to reliance on cultured cell studies, thus hampering our understanding of lipid metabolism and gastrointestinal physiology. Fluorescently-labeled molecules, such as BODIPY-labeled lipids, can reveal lipid-processing events in live zebrafish (Danio rerio) and has expanded our understanding of digestive physiology. This review will cover recent advances from the past two to three years in the use of fluorescence-based imaging techniques in live zebrafish to characterize gastrointestinal physiology in health and disease and to conduct small molecule screens to discover therapeutic compounds. PMID:24187571

  14. Molecular evidence from ascidians for the evolutionary origin of vertebrate cranial sensory placodes.

    PubMed

    Mazet, Francoise; Shimeld, Sebastian M

    2005-07-15

    Cranial sensory placodes are specialised areas of the head ectoderm of vertebrate embryos that contribute to the formation of the cranial sense organs and associated ganglia. Placodes are often considered a vertebrate innovation, and their evolution has been hypothesised as one key adaptation underlying the evolution of active predation by primitive vertebrates. Here, we review recent molecular evidence pertinent to understanding the evolutionary origin of placodes. The development of vertebrate placodes is regulated by numerous genes, including members of the Pax, Six, Eya, Fox, Phox, Neurogenin and Pou gene families. In the sea squirt Ciona intestinalis (a basal chordate and close relative of the vertebrates), orthologues of these genes are deployed in the development of the oral and atrial siphons, structures used for filter feeding by the sessile adult. Our interpretation of these findings is that vertebrate placodes and sea squirt siphon primordia have evolved from the same patches of specialised ectoderm present in the common ancestor of the chordates. PMID:15981200

  15. Diverse of Erythropoiesis Responding to Hypoxia and Low Environmental Temperature in Vertebrates

    PubMed Central

    Maekawa, Shun; Kato, Takashi

    2015-01-01

    Erythrocytes are responsible for transporting oxygen to tissue and are essential for the survival of almost all vertebrate animals. Circulating erythrocyte counts are tightly regulated and respond to erythrocyte mass and oxygen tension. Since the discovery of erythropoietin, the erythropoietic responses to environment and tissue oxygen tension have been investigated in mice and human. Moreover, it has recently become increasingly clear that various environmental stresses could induce the erythropoiesis via various modulating systems, while all vertebrates live in various environments and habitually adapt to environmental stress. Therefore, it is considered that investigations of erythropoiesis in vertebrates provide a lead to the various erythropoietic responses to environmental stress. This paper comparatively introduces the present understanding of erythropoiesis in vertebrates. Indeed, there is a wide range of variations in vertebrates' erythropoiesis. This paper also focused on erythropoietic responses to environmental stress, hypoxia, and lowered temperature in vertebrates. PMID:26557695

  16. The genetic landscape and clinical implications of vertebral anomalies in VACTERL association

    PubMed Central

    Chen, Yixin; Liu, Zhenlei; Chen, Jia; Zuo, Yuzhi; Liu, Sen; Chen, Weisheng; Liu, Gang; Qiu, Guixing; Giampietro, Philip F; Wu, Nan; Wu, Zhihong

    2016-01-01

    VACTERL association is a condition comprising multisystem congenital malformations, causing severe physical disability in affected individuals. It is typically defined by the concurrence of at least three of the following component features: vertebral anomalies (V), anal atresia (A), cardiac malformations (C), tracheo-oesophageal fistula (TE), renal dysplasia (R) and limb abnormalities (L). Vertebral anomaly is one of the most important and common defects that has been reported in approximately 60–95% of all VACTERL patients. Recent breakthroughs have suggested that genetic factors play an important role in VACTERL association, especially in those with vertebral phenotypes. In this review, we summarised the genetic studies of the VACTERL association, especially focusing on the genetic aetiology of patients with vertebral anomalies. Furthermore, genetic reports of other syndromes with vertebral phenotypes overlapping with VACTERL association are also included. We aim to provide a further understanding of the genetic aetiology and a better evidence for genetic diagnosis of the association and vertebral anomalies. PMID:27084730

  17. Insider protection

    SciTech Connect

    Waddoups, I.G.

    1993-07-01

    The government community is broadly addressing the insider threat. The first section of this paper defines protection approaches and the latter sections present various applicable technology developments. The bulk of the paper discusses technology developments applied to (1) personnel and material tracking and inventory, (2) classified document protection, and (3) protecting security systems. The personnel and material tracking system uses a PC based-host to (1) collect information from proximity tags and material movement sensors, (2) apply rules to this input to assure that the ongoing activity meets the site selectable rules and, (3) forward the results to either an automated inventory system or an alarm system. The document protection system uses a PC network to efficiently and securely control classified material which is stored on write-once-read-mostly optical media. The protection of sensor to multiplexer communications in a security system is emphasized in the discussion of protecting security systems.

  18. Altered disc pressure profile after an osteoporotic vertebral fracture is a risk factor for adjacent vertebral body fracture.

    PubMed

    Tzermiadianos, Michael N; Renner, Susan M; Phillips, Frank M; Hadjipavlou, Alexander G; Zindrick, Michael R; Havey, Robert M; Voronov, Michael; Patwardhan, Avinash G

    2008-11-01

    This study investigated the effect of endplate deformity after an osteoporotic vertebral fracture in increasing the risk for adjacent vertebral fractures. Eight human lower thoracic or thoracolumbar specimens, each consisting of five vertebrae were used. To selectively fracture one of the endplates of the middle VB of each specimen a void was created under the target endplate and the specimen was flexed and compressed until failure. The fractured vertebra was subjected to spinal extension under 150 N preload that restored the anterior wall height and vertebral kyphosis, while the fractured endplate remained significantly depressed. The VB was filled with cement to stabilize the fracture, after complete evacuation of its trabecular content to ensure similar cement distribution under both the endplates. Specimens were tested in flexion-extension under 400 N preload while pressure in the discs and strain at the anterior wall of the adjacent vertebrae were recorded. Disc pressure in the intact specimens increased during flexion by 26 +/- 14%. After cementation, disc pressure increased during flexion by 15 +/- 11% in the discs with un-fractured endplates, while decreased by 19 +/- 26.7% in the discs with the fractured endplates. During flexion, the compressive strain at the anterior wall of the vertebra next to the fractured endplate increased by 94 +/- 23% compared to intact status (p < 0.05), while it did not significantly change at the vertebra next to the un-fractured endplate (18.2 +/- 7.1%, p > 0.05). Subsequent flexion with compression to failure resulted in adjacent fracture close to the fractured endplate in six specimens and in a non-adjacent fracture in one specimen, while one specimen had no adjacent fractures. Depression of the fractured endplate alters the pressure profile of the damaged disc resulting in increased compressive loading of the anterior wall of adjacent vertebra that predisposes it to wedge fracture. This data suggests that correction of

  19. Computerized method for detection of vertebral fractures on lateral chest radiographs based on morphometric data

    NASA Astrophysics Data System (ADS)

    Kasai, Satoshi; Li, Feng; Shiraishi, Junji; Li, Qiang; Straus, Christopher; Vokes, Tamara; MacMahon, Heber; Doi, Kunio

    2007-03-01

    Vertebral fractures are the most common osteoporosis-related fractures. It is important to detect vertebral fractures, because they are associated with increased risk of subsequent fractures, and because pharmacologic therapy can reduce the risk of subsequent fractures. Although vertebral fractures are often not clinically recognized, they can be visualized on lateral chest radiographs taken for other purposes. However, only 15-60% of vertebral fractures found on lateral chest radiographs are mentioned in radiology reports. The purpose of this study was to develop a computerized method for detection of vertebral fractures on lateral chest radiographs in order to assist radiologists' image interpretation. Our computerized method is based on the automated identification of upper and lower vertebral edges. In order to develop the scheme, radiologists provided morphometric data for each identifiable vertebra, which consisted of six points for each vertebra, for 25 normals and 20 cases with severe fractures. Anatomical information was obtained from morphometric data of normal cases in terms of vertebral heights, heights of vertebral disk spaces, and vertebral centerline. Computerized detection of vertebral fractures was based on the reduction in the heights of fractured vertebrae compared to adjacent vertebrae and normal reference data. Vertebral heights from morphometric data on normal cases were used as reference. On 138 chest radiographs (20 with fractures) the sensitivity of our method for detection of fracture cases was 95% (19/20) with 0.93 (110/118) false-positives per image. In conclusion, the computerized method would be useful for detection of potentially overlooked vertebral fractures on lateral chest radiographs.

  20. Odontogenic Pain as the Principal Presentation of Vertebral Artery Pseudoaneurysm; a Case Report

    PubMed Central

    Zenteno, Marco; Alvis-Miranda, Hernando Raphael; Lee, Angel; Moscote-Salazar, Luis Rafael

    2015-01-01

    Dissection of the vertebral artery is an important but rare cause of cerebrovascular accidents. Here we report a 48-year-old man with toothache since 4 days before who presented to the emergency department with neck pain and final diagnosis of dissecting right vertebral artery pseudoaneurysm. To our knowledge, this maybe the first report of odontogenic pain as the first manifestation of vertebral artery pseudoaneurysm in the literatures. PMID:26495399

  1. Dipeptide frequencies in proteins and the CpG deficiency in vertebrate DNA.

    PubMed

    Bullock, E; Elton, R A

    1972-12-01

    Analysis of vertebrate protein sequences totalling 4040 residues shows that amino acids with a high proportion of codons ending in C occur with significantly reduced frequency before amino acids whose codons start with G. This effect is not shown by "control" bacterial protein sequences. The consequent implication of shortage of XXC. GXX codon pairs in vertebrate messenger RNA is discussed in relation to the extreme rarity of the base doublet CpG in vertebrate DNA. PMID:24173492

  2. Ancient origin of lubricated joints in bony vertebrates

    PubMed Central

    Askary, Amjad; Smeeton, Joanna; Paul, Sandeep; Schindler, Simone; Braasch, Ingo; Ellis, Nicholas A; Postlethwait, John; Miller, Craig T; Crump, J Gage

    2016-01-01

    Synovial joints are the lubricated connections between the bones of our body that are commonly affected in arthritis. It is assumed that synovial joints first evolved as vertebrates came to land, with ray-finned fishes lacking lubricated joints. Here, we examine the expression and function of a critical lubricating protein of mammalian synovial joints, Prg4/Lubricin, in diverse ray-finned fishes. We find that Prg4 homologs are specifically enriched at the jaw and pectoral fin joints of zebrafish, stickleback, and gar, with genetic deletion of the zebrafish prg4b gene resulting in the same age-related degeneration of joints as seen in lubricin-deficient mice and humans. Our data support lubricated synovial joints evolving much earlier than currently accepted, at least in the common ancestor of all bony vertebrates. Establishment of the first arthritis model in the highly regenerative zebrafish will offer unique opportunities to understand the aetiology and possible treatment of synovial joint disease. DOI: http://dx.doi.org/10.7554/eLife.16415.001 PMID:27434666

  3. Evolution of the protease-activated receptor family in vertebrates

    PubMed Central

    JIN, MIN; YANG, HAI-WEI; TAO, AI-LIN; WEI, JI-FU

    2016-01-01

    Belonging to the G protein-coupled receptor (GPcr) family, the protease-activated receptors (Pars) consist of 4 members, PAR1-4. PARs mediate the activation of cells via thrombin, serine and other proteases. Such protease-triggered signaling events are thought to be critical for hemostasis, thrombosis and other normal pathological processes. In the present study, we examined the evolution of PARs by analyzing phylogenetic trees, chromosome location, selective pressure and functional divergence based on the 169 functional gene alignment sequences from 57 vertebrate gene sequences. We found that the 4 PARs originated from 4 invertebrate ancestors by phylogenetic trees analysis. The selective pressure results revealed that only PAR1 appeared by positive selection during its evolution, while the other PAR members did not. In addition, we noticed that although these PARs evolved separately, the results of functional divergence indicated that their evolutional rates were similar and their functions did not significantly diverge. The findings of our study provide valuable insight into the evolutionary history of the vertebrate PAR family. PMID:26820116

  4. Neural Differentiation Modulates the Vertebrate Brain Specific Splicing Program

    PubMed Central

    Madgwick, Alicia; Fort, Philippe; Hanson, Peter S.; Thibault, Philippe; Gaudreau, Marie-Claude; Lutfalla, Georges; Möröy, Tarik; Abou Elela, Sherif; Chaudhry, Bill; Elliott, David J.; Morris, Christopher M.; Venables, Julian P.

    2015-01-01

    Alternative splicing patterns are known to vary between tissues but these patterns have been found to be predominantly peculiar to one species or another, implying only a limited function in fundamental neural biology. Here we used high-throughput RT-PCR to monitor the expression pattern of all the annotated simple alternative splicing events (ASEs) in the Reference Sequence Database, in different mouse tissues and identified 93 brain-specific events that shift from one isoform to another (switch-like) between brain and other tissues. Consistent with an important function, regulation of a core set of 9 conserved switch-like ASEs is highly conserved, as they have the same pattern of tissue-specific splicing in all vertebrates tested: human, mouse and zebrafish. Several of these ASEs are embedded within genes that encode proteins associated with the neuronal microtubule network, and show a dramatic and concerted shift within a short time window of human neural stem cell differentiation. Similarly these exons are dynamically regulated in zebrafish development. These data demonstrate that although alternative splicing patterns often vary between species, there is nonetheless a core set of vertebrate brain-specific ASEs that are conserved between species and associated with neural differentiation. PMID:25993117

  5. Controversial Issues in Kyphoplasty and Vertebroplasty in Osteoporotic Vertebral Fractures

    PubMed Central

    Papanastassiou, Ioannis D.; Filis, Andreas; Gerochristou, Maria A.; Vrionis, Frank D.

    2014-01-01

    Kyphoplasty (KP) and vertebroplasty (VP) have been successfully employed for many years for the treatment of osteoporotic vertebral fractures. The purpose of this review is to resolve the controversial issues raised by the two randomized trials that claimed no difference between VP and SHAM procedure. In particular we compare nonsurgical management (NSM) and KP and VP, in terms of clinical parameters (pain, disability, quality of life, and new fractures), cost-effectiveness, radiological variables (kyphosis correction and vertebral height restoration), and VP versus KP for cement extravasation and complications profile. Cement types and optimal filling are analyzed and technological innovations are presented. Finally unipedicular/bipedicular techniques are compared. Conclusion. VP and KP are superior to NSM in clinical and radiological parameters and probably more cost-effective. KP is superior to VP in sagittal balance improvement and cement leaking. Complications are rare but serious adverse events have been described, so caution should be exerted. Unilateral procedures should be pursued whenever feasible. Upcoming randomized trials (CEEP, OSTEO-6, STIC-2, and VERTOS IV) will provide the missing link. PMID:24724106

  6. Genetic control of segmentation of axial structures in vertebrates

    SciTech Connect

    Mglinets, V.A.

    1995-07-01

    The processes of segmentation of axial structures in vertebrates during early embryonic development are reviewed. These processes include the formation of neuromeres, somitomeres, cranial ganglia, and branchial arches in the head and of neuromeres, somites, spinal ganglia, and motor nerves in the body of the embryo. The class of vertebrate homeobox genes Hox is described with respect to the arrangement of these genes in four clusters, the structural and functional similarity of paralogues in gene subfamilies, and the type of Hox gene expression in the head and body. A hypothesis concerning the existence of a genetic Hox code, determining the fate of individual segments in neuroectodermal and mesenchymal derivatives, is discussed. In the context of this hypothesis, phenotypic expression of the mutant Hox genes, accompanied by the loss of their function and cases of excessive and ectopic expression of Hox genes, are analyzed. Only in such cases do mutant phenotypes demonstrate symptoms of actual homeotic transformation, in which specific segmental structures are substituted by their homologues, as has been described for homeotic mutations in Drosophila. 56 refs., 1 fig.

  7. Bacterial endocarditis presenting as acute vertebral osteomyelitis: 14 cases.

    PubMed

    Ninet, J; Gayet, J L; Etienne, J; Bonvoisin, B; Vignon, E; Berthou, J D; Delahaye, J P; Pasquier, J; Delaye, J; Normand, J

    1984-10-01

    Association between bacterial endocarditis (BE) and vertebral osteomyelitis (VO) has infrequently been noted. In a retrospective analysis of BE (280 cases) and VO (150 cases) 14 cases were found to have this association. There were 12 males and 2 females, ages ranging from 39 to 72 years, mean age 56.6. Blood cultures were positive for Streptococcus viridans (6 cases). Str. faecalis (4 cases), staphylococcus (2 cases), Gram negative bacteria (1 case). Organism was not isolated in one case. Fever and severe back pain antedate the diagnosis of VO 3.5 and 2.5 months. X rays films of the spine and bone scans (4 cases) revealed lumbar (6 cases) or cervical (4 cases), or dorsal (3 cases) or combined cervical and dorsal (1 case) locations. History of murmur (4 cases) and development of mitral (8 cases) or aortic (4 cases) or combined mitral and aortic (2 cases) insufficiencies were consistent with concomitant BE. Echocardiogram revealed vegetations in 6 out of 9 cases. Patients received antibiotic therapy for 3.5 months. Ten patients were cured with antibiotics only, 4 required valve replacement. One died. Thus age, sex, history of heart disease, valvular involvement, duration of symptoms prior to admission and bacteriological pictures are the same in BE with VO as in BE without VO. Survival rates are also the same if early recognition of BE and VO with prompt and prolonged antibiotic therapy may prevent severe haemodynamic or vertebral problems. PMID:6519073

  8. A mixed-mating strategy in a hermaphroditic vertebrate

    PubMed Central

    Mackiewicz, Mark; Tatarenkov, Andrey; Turner, Bruce J; Avise, John C

    2006-01-01

    Mixed-mating systems, in which hermaphrodites can either self-fertilize or outcross, are common in many species of plants and invertebrates and have been informative models for studying the selective forces that can maintain both inbreeding and outbreeding in populations. Here, we document a remarkable instance of evolutionary convergence to an analogous mixed mating system by a vertebrate, the mangrove killifish (Kryptolebias marmoratus). In this androdioecious species, most individuals are simultaneous hermaphrodites that characteristically self-fertilize, resulting in local populations that consist of (nearly) homozygous lines. Most demes are also genetically diverse, an observation traditionally attributed to de novo mutation coupled with high levels of inter-site migration. However, data presented here, from a survey of 35 microsatellite loci in Floridian populations, show that genotypic diversity also stems proximally from occasional outcross events that release ‘explosions’ of transient recombinant variation. The result is a local population genetic pattern (of extensive genotypic variety despite low but highly heterogeneous intra-individual heterozygosities) that differs qualitatively from the genetic architectures known in any other vertebrate species. Advantages of a mixed-mating strategy in K. marmoratus probably relate to this fish's solitary lifestyle and its ability to colonize new habitats. PMID:16959634

  9. Cervical vertebral strain measurements under axial and eccentric loading.

    PubMed

    Pintar, F A; Yoganandan, N; Pesigan, M; Reinartz, J; Sances, A; Cusick, J F

    1995-11-01

    The mid to lower cervical spine is a common site for compression related injury. In the present study, we determined the patterns of localized strain distribution in the anterior aspect of the vertebral body and in the lateral masses of lower cervical three-segment units. Miniature strain gages were mounted to human cadaveric vertebrae. Each preparation was line-loaded using a knife-edge oriented in the coronal plane that was moved incrementally from anterior to posterior to induce compression-flexion or compression-extension loading. Uniform compressive loading and failure runs were also conducted. Failure tests indicated strain shifting to "restabilize" the preparation after failure of a component. Under these various compressive loading vectors, the location which resulted in the least amount of deformation for a given force application (i.e., stiffest axis) was quantified to be in the region between 0.5- 1.0 cm anterior to the posterior longitudinal ligament. The location in which line-loading produced no rotation (i.e., balance point) was in this region; it was also close to where the vertebral body strains change from compressive to tensile. Strain values from line loading in this region produced similar strains as recorded under uniform compressive loading, and this was also the region of minimum strain. The region of minimum strain was also more pronounced under higher magnitudes of loading, suggesting that as the maximum load carrying capacity is reached the stiffest axis becomes more well defined. PMID:8748531

  10. Of mice and genes: evolution of vertebrate brain development

    NASA Technical Reports Server (NTRS)

    Fritzsch, B.

    1998-01-01

    In this review the current understanding of genetic and molecular evolution of development, in particular the formation of the major axis of bilateral animals, is critically evaluated, and the early pattern formation in the hindbrain is related as much as possible to these processes. On the genetic level it is proposed that the exuberant multiplication of regulatory genes compared to that of structural genes relates to the increased flexibility of early vertebrate development. In comparisons to fruit flies, many conserved genes are found to be expressed very differently, while many others seem to reflect a comparable pattern and thus suggest a conservation of function. Even genes with a largely conserved pattern of expression may change the level at which they are expressed and the mechanisms by which they are regulated in their expression. Evolution and development of hindbrain motoneurons is reviewed, and it is concluded that both comparative data as well as more recent experimental data suggest a limited importance for the rhombomeres. Clearly, many cell fate-specifying processes work below the level of rhombomeres or in the absence of rhombomeres. It is suggested that more comparative developmental data are needed to establish firmly the relationship between homeobox genes and rhombomere specification in vertebrates other than a few model species.

  11. Homology and Convergence in Vertebrate and Invertebrate Nervous Systems

    NASA Astrophysics Data System (ADS)

    Sandeman, David

    Each year the meeting of the American Neuroscience Society attracts over 20,000 members, reflecting the explosion of interest in this field that has occurred over the past few decades. Researchers from many disciplines are focusing their skills on the investigation of every aspect of nervous systems, and neuroscience now encompasses the entire range of endeavour from the study of the single molecules that make up neural membranes to the non-invasive observation of neural function in animals behaving in their natural environments. Advances over the past three decades in our understanding of nervous systems are impressive and come from a multifaceted approach to the study of both vertebrate and invertebrate animals. An almost unexpected by-product of the parallel investigation of vertebrate and invertebrate nervous systems that is explored in this article is the emergent view of an intricate web of evolutionary homology and convergence exhibited in the structure and function of the nervous systems of these two large, paraphyletic groups of animals.

  12. 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.

  13. Ancient origin of lubricated joints in bony vertebrates.

    PubMed

    Askary, Amjad; Smeeton, Joanna; Paul, Sandeep; Schindler, Simone; Braasch, Ingo; Ellis, Nicholas A; Postlethwait, John; Miller, Craig T; Crump, J Gage

    2016-01-01

    Synovial joints are the lubricated connections between the bones of our body that are commonly affected in arthritis. It is assumed that synovial joints first evolved as vertebrates came to land, with ray-finned fishes lacking lubricated joints. Here, we examine the expression and function of a critical lubricating protein of mammalian synovial joints, Prg4/Lubricin, in diverse ray-finned fishes. We find that Prg4 homologs are specifically enriched at the jaw and pectoral fin joints of zebrafish, stickleback, and gar, with genetic deletion of the zebrafish prg4b gene resulting in the same age-related degeneration of joints as seen in lubricin-deficient mice and humans. Our data support lubricated synovial joints evolving much earlier than currently accepted, at least in the common ancestor of all bony vertebrates. Establishment of the first arthritis model in the highly regenerative zebrafish will offer unique opportunities to understand the aetiology and possible treatment of synovial joint disease. PMID:27434666

  14. Mortality after hip fracture with vertebral compression fracture is poor.

    PubMed

    Imai, Norio; Endo, Naoto; Hoshino, Tadashi; Suda, Ken; Miyasaka, Dai; Ito, Tomoyuki

    2016-01-01

    Due to the increasing elderly population, the prevalence of osteoporotic hip fractures in Japanese patients continues to rise. It is well established that patients with either hip fracture or both symptomatic and asymptomatic morphometric vertebral compression fracture (VCF) have a poor health prognosis compared with the general population. The purpose of this study was to retrospectively investigate vertebral fracture rates among patients with hip fracture and their influence on mortality. We examined 182 cases of osteoporotic hip fracture in patients admitted to our institution between January 2009 and May 2011. The average age at the time of fracture was 85 years. Radiographs of the lumbar spine were obtained from all of the participants and the lateral spinal radiographs were examined for evidence of VCF. The patients were classified into two groups, those with VCF and those without. A VCF was identified in approximately 78 % of the patients. The mortality rate 1 year after the hip fracture was approximately 22 % and it was significantly higher in patients with VCF. Through multivariate statistics we found that VCF, post-operative complication, loss of ambulation after operation and medication for osteoporosis were statistically significant. In other words, VCF, post-operative complication and loss of ambulation were considered to be poor prognostic factors and medication for osteoporosis was likely to improve the prognosis. We concluded that the risk of mortality after hip fracture is significantly greater in patients who also have VCF compared to patients without VCF, and that medication for osteoporosis is likely to improve prognosis. PMID:25501699

  15. Making sense-data-based simulations of vertebrate limb development.

    PubMed

    Iber, Dagmar; Zeller, Rolf

    2012-12-01

    Limb bud development has been studied for decades and contributed a wealth of knowledge to our understanding of the molecular and cellular mechanisms that govern organogenesis in vertebrate embryos. However, the general regulatory paradigms that underlie the functional and structural organization of complex systems such as developing limb buds have remained largely elusive. A significant number of mathematical theories have been proposed to explain these developmental processes, but have rarely been validated by experimental analysis. In the age of systems biology, experimental and mathematical approaches have become interlinked and enable the experimental validation of computational models by molecular and genetic analysis. This in turn allows refinement of the mathematical simulations such that simulating limb bud development becomes increasingly more realistic. The resulting models not only detect inconsistencies in the interpretation of experimental data, but their predictive power facilitates identification of key regulatory interactions and definition of so-called core and accessory mechanisms. The ongoing integrative analysis of vertebrate limb organogenesis indicates that these network simulations may be suitable for in silico genetics, that is the computational modeling of complex loss-of-functions and gain-of-functions states. Such in silico genetic approaches will permit the simulation of complex mutant phenotypes tedious or impossible to generate using mouse molecular genetics. PMID:23266216

  16. Clinical, Genetic and Environmental Factors Associated with Congenital Vertebral Malformations

    PubMed Central

    Giampietro, P.F.; Raggio, C.L.; Blank, R.D.; McCarty, C.; Broeckel, U.; Pickart, M.A.

    2013-01-01

    Congenital vertebral malformations (CVM) pose a significant health problem because they can be associated with spinal deformities, such as congenital scoliosis and kyphosis, in addition to various syndromes and other congenital malformations. Additional information remains to be learned regarding the natural history of congenital scoliosis and related health problems. Although significant progress has been made in understanding the process of somite formation, which gives rise to vertebral bodies, there is a wide gap in our understanding of how genetic factors contribute to CVM development. Maternal diabetes during pregnancy most commonly contributes to the occurrence of CVM, followed by other factors such as hypoxia and anticonvulsant medications. This review highlights several emerging clinical issues related to CVM, including pulmonary and orthopedic outcome in congenital scoliosis. Recent breakthroughs in genetics related to gene and environment interactions associated with CVM development are discussed. The Klippel-Feil syndrome which is associated with cervical segmentation abnormalities is illustrated as an example in which animal models, such as the zebrafish, can be utilized to provide functional evidence of pathogenicity of identified mutations. PMID:23653580

  17. Vertebrate Neural Stem Cells: Development, Plasticity, and Regeneration.

    PubMed

    Shimazaki, Takuya

    2016-03-25

    Natural recovery from disease and damage in the adult mammalian central nervous system (CNS) is limited compared with that in lower vertebrate species, including fish and salamanders. Species-specific differences in the plasticity of the CNS reflect these differences in regenerative capacity. Despite numerous extensive studies in the field of CNS regeneration, our understanding of the molecular mechanisms determining the regenerative capacity of the CNS is still relatively poor. The discovery of adult neural stem cells (aNSCs) in mammals, including humans, in the early 1990s has opened up new possibilities for the treatment of CNS disorders via self-regeneration through the mobilization of these cells. However, we now know that aNSCs in mammals are not plastic enough to induce significant regeneration. In contrast, aNSCs in some regenerative species have been found to be as highly plastic as early embryonic neural stem cells (NSCs). We must expand our knowledge of NSCs and of regenerative processes in lower vertebrates in an effort to develop effective regenerative treatments for damaged CNS in humans. PMID:26853878

  18. [Revascularization of the carotid and vertebral arteries in the elderly].

    PubMed

    Illuminati, G; Bezzi, M; D'Urso, A; Giacobbi, D; Ceccanei, G; Vietri, F

    2004-01-01

    From January 1994 to July 2004, 323 patients underwent 348 revascularization of carotid bifurcation for atherosclerotic stenoses. Eighty eight patients (group A) were 75 year-old or older, whereas 235 (group B) were younger than 75 years. Postoperative mortality/neurologic morbidity rate was 1% in group A, and 1.4% in group B. At 5 years, patency and freedom from symptoms/stroke were, respectively, 91% and 92% in group A, and 89% and 91% in group B. None of these differences was statistically significant. In the same time period, 26 internal carotid arteries were revascularized in 24 patients, 75 or more aged, for a symptomatic kinking. Postoperative mortality/morbidity rate was absent, whereas, at 5 years, patency and freedom from symptoms/stroke were, respectively, 88% and 92%. Twelve vertebral arteries were revascularized in 12 patients, 75 or more aged, for invalidating symptoms of vertebrobasilar insufficiency. Postoperative mortality/neurologic morbidity rate was absent. In one case postoperative recurrence of symptoms occurred, despite a patent revascularization. Patency and freedom from symptoms/stroke were 84% and 75%, at 5 years. Revascularization of carotid and vertebral arteries in the elderly can be accomplished with good results, superposable to those of standard revascularization of carotid bifurcation in a younger patients' population. PMID:15803810

  19. Anterior-posterior patterning and segmentation of the vertebrate head

    PubMed Central

    Schilling, Thomas F.

    2008-01-01

    Segmentation of the vertebrate head emerges out of earlier processes that establish the anterior-posterior (A-P) axis. Recent genetic studies and comparisons across species have led to a better understanding of the links between A-P patterning and segmentation. These point to similar signals acting on both head and trunk, such as retinoic acid and fibroblast growth factors. These form interacting networks of diffusible morphogen gradients that pattern both hindbrain rhombomeres and mesodermal somites. New computational models, particularly for retinoic acid, have revealed how morphogen gradients are established and made robust to changes in signaling levels. However, the orientations of these gradients, as well as how they interact to generate segments, differ remarkably between germ layers and body regions. Thus, the vertebrate head is, in part, built through modifications of the same processes that link A-P patterning and segmentation in the trunk, but fundamental differences in how these processes are deployed lend further doubt to the notion that head and trunk segments are homologous. PMID:21669823

  20. Vertebral sarcoidosis: demonstration of bone involvement by computerized axial tomography

    SciTech Connect

    Dinerstein, S.L.; Kovarsky, J.

    1984-08-01

    A report is given of a rare case of vertebral sarcoidosis with negative conventional spinal x-ray films, yet with typical cystic lesions of the spine found incidentally during abdominal computerized axial tomography (CAT). The patient was a 28-year-old black man, who was admitted for evaluation of a 1 1/2-year history of diffuse myalgias, intermittent fever to 102 F orally, bilateral hilar adenopathy, and leukopenia. A technetium polyphosphate bone scan revealed diffuse areas of increased uptake over the sternum, entire vertebral column, and pelvis. Conventional x-ray films of the cervical, thoracic, and lumbar spine, and an AP view of the pelvis were all normal. Chest x-ray film revealed only bilateral hilar adenopathy. During the course of an extensive negative evaluation for infection, an abdominal CAT scan was done, showing multiple, small, sclerotic-rimmed cysts at multiple levels of the lower thoracic and lumbar spine. Bone marrow biopsy revealed only changes consistent with anemia of chronic disease. Mediastinal lymph node biopsy revealed noncaseating granulomas. A tentative diagnosis of sarcoidosis was made, and treatment with prednisone, isoniazid and rifampin was begun. Within two weeks of initiation of prednisone therapy, the patient was symptom-free. A repeat technetium polyphosphate bone scan revealed only a small residual area of mildly increased uptake over the upper thoracic vertebrae.

  1. [Skin derivatives in ontogeny and phylogeny of vertebrates].

    PubMed

    Chernova, O F

    2009-01-01

    The skin of vertebrates has numerous and diverse derivatives, either located within the epithelial sheet itself (glands) or extending above its surface (teeth, scales, feathers, hairs, etc.). Many of them have a modular structure and constitute structural-functional units. Ontogenetically, all skin derivatives are of ectomesodermal origin, and their morphogenesis is subject to metabolic control, heterochronies (divergence in the timing of origination and development), and regulation by means of tissue interactions and molecular signaling via similar pathways. The diversification (origination of morphological diversity) of skin derivatives within the same morphological type is explained by the development of new generations of ectomesodermal structures separated be heterochronies and regulated by changes in the gradients of molecular signaling pathways under the influence of environmental factors. Evolutionary relationships between the majority of skin derivatives are obscure, except for teeth and glands associated with sensory organs, which evolved together with the latter. Apparently, many vertebrate skin derivatives (scales, feathers, hairs, and glands) originated as innovations at nodal stages of phylogeny and subsequently evolved convergently or in parallel. PMID:19391480

  2. The Mechanism of Germline Sex Determination in Vertebrates.

    PubMed

    Nishimura, Toshiya; Tanaka, Minoru

    2016-07-01

    Germ cells are the common cells of origin for the two different types of gametes, sperm and eggs. In vertebrates so far examined, the sex of germ cells is determined by gonadal somatic cells. However, influenced by the somatic cells, how germ cells adopt their sexual fates by intrinsic factors has long been unclear in vertebrates. We recently identified forkhead box L3 (FOXL3) as a germ cell-intrinsic factor involved in the sperm-egg fate decision in the teleost fish medaka (Oryzias latipes). On the basis of the results obtained by the analysis of foxl3/FOXL3 expression and loss-of-function mutants, we review when and how germ cell sex is regulated non-cell-autonomously and cell-autonomously. We then discuss the fact that the germline sex determination pathway is genetically distinct from other essential gametogenic pathways such as meiotic entry and the establishment of germline stem cells. Another extraordinary finding in the foxl3 mutant is that functional sperm can be produced in the ovary, which provides a new notion that gametogenesis can proceed regardless of the sex of the surrounding somatic cells once the sexual identity of germ cells is established in medaka. PMID:27009043

  3. Vertebrate sex-determining genes play musical chairs.

    PubMed

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

    2016-01-01

    Sexual reproduction is one of the most highly conserved processes in evolution. However, the genetic and cellular mechanisms making the decision of whether the undifferentiated gonad of animal embryos develops either towards male or female are manifold and quite diverse. In vertebrates, sex-determining mechanisms range from environmental to simple or complex genetic mechanisms and different mechanisms have evolved repeatedly and independently. In species with simple genetic sex-determination, master sex-determining genes lying on sex chromosomes drive the gonadal differentiation process by switching on a developmental program, which ultimately leads to testicular or ovarian differentiation. So far, very few sex-determining genes have been identified in vertebrates and apart from mammals and birds, these genes are apparently not conserved over a larger number of related orders, families, genera, or even species. To fill this knowledge gap and to better explore genetic sex-determination, we propose a strategy (RAD-Sex) that makes use of next-generation sequencing technology to identify genetic markers that define sex-specific segments of the male or female genome. PMID:27291506

  4. Regeneration versus scarring in vertebrate appendages and heart.

    PubMed

    Jaźwińska, Anna; Sallin, Pauline

    2016-01-01

    Injuries to complex human organs, such as the limbs and the heart, result in pathological conditions, for which we often lack adequate treatments. While modern regenerative approaches are based on the transplantation of stem cell-derived cells, natural regeneration in lower vertebrates, such as zebrafish and newts, relies predominantly on the intrinsic plasticity of mature tissues. This property involves local activation of the remaining material at the site of injury to promote cell division, cell migration and complete reproduction of the missing structure. It remains an unresolved question why adult mammals are not equally competent to reactivate morphogenetic programmes. Although organ regeneration depends strongly on the proliferative properties of cells in the injured tissue, it is apparent that various organismic factors, such as innervation, vascularization, hormones, metabolism and the immune system, can affect this process. Here, we focus on a correlation between the regenerative capacity and cellular specialization in the context of functional demands, as illustrated by appendages and heart in diverse vertebrates. Elucidation of the differences between homologous regenerative and non-regenerative tissues from various animal models is essential for understanding the applicability of lessons learned from the study of regenerative biology to clinical strategies for the treatment of injured human organs. PMID:26414617

  5. 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

  6. The Migration Matrix: Marine Vertebrate Movements in Magnetic Coordinate Space

    NASA Astrophysics Data System (ADS)

    Horton, T. W.; Holdaway, R. N.; Clapham, P. J.; Zerbini, A. N.; Andriolo, A.; Hays, G. C.; Egevang, C.; Domeier, M. L.; Lucas, N.

    2011-12-01

    Determining how vertebrates navigate during their long-distance migrations remains one of the most enduring and fundamental challenges of behavioral ecology. It is widely accepted that spatial orientation relative to a reference datum is a fundamental requirement of long-distance return migration between seasonal habitats, and a variety of viable positional and directional orientation cues, including the sun, stars, and magnetic field, have been documented experimentally. However, a fundamental question remains unanswered: Are empirically observed migratory movements compatible with modern theoretical frameworks of spatial orientation? To address this question, we analysed leatherback turtle (Dermochelys coriacea), arctic tern (Sterna paradisaea), humpback whale (Megaptera novaeangliae), and great white shark (Carcharodon carcharias) track maps, frequency distribution diagrams and time-series plots of animal locations in spherical magnetic coordinate space. Our analyses indicates that, although individual migration tracks are spatially and temporally distinct, vertebrate movements are non-randomly distributed in all three spherical magnetic coordinates (i.e. intensity, inclination, and declination). Stop-over locations, migratory destinations, and re-orientation points occur at similar magnetic coordinate locations, relative to tagging areas, in all four species, suggesting that a common system of magnetic orientation likely informs the navigational behaviors of these phylogenetically diverse taxa. Although our analyses demonstrate that the experiment-derived 'magnetic map' goal orientation theoretical framework of animal navigation is compatible with remotely-sensed migration track data, they also indicate that magnetic information is complemented by spatially and temporally contingent celestial stimuli during navigation.

  7. Ischemic spinal cord infarction in children without vertebral fracture

    PubMed Central

    Nance, Jessica R.; Golomb, Meredith R.

    2007-01-01

    Spinal cord infarction in children is a rare condition which is becoming more widely recognized. There are few reports in the pediatric literature characterizing etiology, diagnosis, treament and prognosis. The risk factors for pediatric ischemic spinal cord infarction include obstruction of blood flow associated with cardiovascular compromise or malformation, iatrogenic or traumatic vascular inujury, cerebellar herniation, thrombotic or embolic disease, infection, and vasculitis. In many children the cause of spinal cord ischemia in the absence of vertebral fracture is unknown. Imaging diagnosis of spinal cord ischemia is often difficult due to the small transverse area of the cord, cerebrospinal fluid artifact and inadequate resolution of MRI. Physical therapy is the most important treatment option. The prognosis is dependent on the level of spinal cord damage, early identification and reversal of ischemia, and follow-up with intensive physical therapy and medical support. In addition to summarizing the literature regarding spinal cord infarction in children without vertebral fracture, this review article adds two cases to the literature which highlight the difficulties and controversies in the management of this condition. PMID:17437902

  8. Late Permian vertebrate community of the Pranhita Godavari valley, India

    NASA Astrophysics Data System (ADS)

    Ray, Sanghamitra; Bandyopadhyay, Saswati

    2003-03-01

    The Kundaram Formation of the Pranhita-Godavari valley yields the only Late Permian multispecies terrestrial vertebrate assemblage from India. This includes various medium and small dicynodonts such as Endothiodon, Oudenodon, Kingoria, Emydops, Cistecephalus and Pristerodon. At present two species of Endothiodon ( E. mahalanobisi and E. uniseries) are known. Apart from these dicynodonts, the Kundaram vertebrate fauna also contains a medium-sized gorgonopsian and a small captorhinid. The material, from the red mudstone dominated Kundaram Formation, includes numerous isolated, disarticulated skulls and lower jaws. Postcranial elements are relatively rare except for a few broken limb ends and vertebrae. The bones are encrusted by iron rich matrix and most of them had suffered deformation. This skull dominant accumulation is attributed to prolonged aerial exposure prior to burial resulting in disarticulation of the skeletons and subsequent inundation by floodwater. The limb bones and other postcranial elements of the already disarticulated skeletons were winnowed out by shallow competent flow while the relatively heavier skulls and lower jaws resisting transportation were buried near the site of death. The Late Permian scenario of the Pranhita-Godavari valley was characterised by the dominance of herbivores. This abundance of herbivores at the base and the presence of relatively few carnivores and omnivores at the top of the Kundaram food pyramid indicate a trophic structure similar to that of the modern-day terrestrial ecosystem.

  9. Neural differentiation modulates the vertebrate brain specific splicing program.

    PubMed

    Madgwick, Alicia; Fort, Philippe; Hanson, Peter S; Thibault, Philippe; Gaudreau, Marie-Claude; Lutfalla, Georges; Möröy, Tarik; Abou Elela, Sherif; Chaudhry, Bill; Elliott, David J; Morris, Christopher M; Venables, Julian P

    2015-01-01

    Alternative splicing patterns are known to vary between tissues but these patterns have been found to be predominantly peculiar to one species or another, implying only a limited function in fundamental neural biology. Here we used high-throughput RT-PCR to monitor the expression pattern of all the annotated simple alternative splicing events (ASEs) in the Reference Sequence Database, in different mouse tissues and identified 93 brain-specific events that shift from one isoform to another (switch-like) between brain and other tissues. Consistent with an important function, regulation of a core set of 9 conserved switch-like ASEs is highly conserved, as they have the same pattern of tissue-specific splicing in all vertebrates tested: human, mouse and zebrafish. Several of these ASEs are embedded within genes that encode proteins associated with the neuronal microtubule network, and show a dramatic and concerted shift within a short time window of human neural stem cell differentiation. Similarly these exons are dynamically regulated in zebrafish development. These data demonstrate that although alternative splicing patterns often vary between species, there is nonetheless a core set of vertebrate brain-specific ASEs that are conserved between species and associated with neural differentiation. PMID:25993117

  10. Estimation of stature from radiologic anthropometry of the lumbar vertebral dimensions in Chinese.

    PubMed

    Zhang, Kui; Chang, Yun-feng; Fan, Fei; Deng, Zhen-hua

    2015-11-01

    The recent study was to assess the relationship between the radiologic anthropometry of the lumbar vertebral dimensions and stature in Chinese and to develop regression formulae to estimate stature from these dimensions. A total of 412 normal, healthy volunteers, comprising 206 males and 206 females, were recruited. The linear regression analysis were performed to assess the correlation between the stature and lengths of various segments of the lumbar vertebral column. Among the regression equations created for single variable, the predictive value was greatest for the reconstruction of stature from the lumbar segment in both sexes and subgroup analysis. When individual vertebral body was used, the heights of posterior vertebral body of L3 gave the most accurate results for male group, the heights of central vertebral body of L1 provided the most accurate results for female group and female group with age above 45 years, the heights of central vertebral body of L3 gave the most accurate results for the groups with age from 20-45 years for both sexes and the male group with age above 45 years. The heights of anterior vertebral body of L5 gave the less accurate results except for the heights of anterior vertebral body of L4 provided the less accurate result for the male group with age above 45 years. As expected, multiple regression equations were more successful than equations derived from a single variable. The research observations suggest lumbar vertebral dimensions to be useful in stature estimation among Chinese population. PMID:26593994

  11. Coiling occlusion of the vertebral artery for a patient with recurrent posterior circulation TIAs.

    PubMed

    Chembala, J; Jadun, C; Natarajan, I; Roffe, C

    2013-02-01

    Recurrent posterior circulation infarcts frequently involve multiple vascular territories, suggesting an embolic source. We describe a patient with left vertebral artery occlusion who had recurrent transient ischaemic attacks due to cerebral embolization originating from the occluded vertebral artery in spite of optimal anticoagulant and antithrombotic treatment. This was successfully managed by coiling occlusion of the vertebral artery with no recurrence of symptoms over one year of follow-up. To our knowledge, this is the first report of coiling occlusion in the treatment of recurrent vertebral artery embolization. PMID:23859172

  12. Lack of evidence of WNT3A as a candidate gene for congenital vertebral malformations

    PubMed Central

    Ghebranious, Nader; Raggio, Cathleen L; Blank, Robert D; McPherson, Elizabeth; Burmester, James K; Ivacic, Lynn; Rasmussen, Kristen; Kislow, Jennifer; Glurich, Ingrid; Jacobsen, F Stig; Faciszewski, Thomas; Pauli, Richard M; Boachie-Adjei, Oheneba; Giampietro, Philip F

    2007-01-01

    Background Prior investigations have not identified a major locus for vertebral malformations, providing evidence that there is genetic heterogeneity for this condition. WNT3A has recently been identified as a negative regulator of Notch signaling and somitogenesis. Mice with mutations in Wnt3a develop caudal vertebral malformations. Because congenital vertebral malformations represent a sporadic occurrence, linkage approaches to identify genes associated with human vertebral development are not feasible. We hypothesized that WNT3A mutations might account for a subset of congenital vertebral malformations. Methods A pilot study was performed using a cohort of patients with congenital vertebral malformations spanning the entire vertebral column was characterized. DNA sequence analysis of the WNT3A gene in these 50 patients with congenital vertebral malformations was performed. Results A female patient of African ancestry with congenital scoliosis and a T12-L1 hemivertebrae was found to be heterozygous for a missense variant resulting in the substitution of alanine by threonine at codon 134 in highly conserved exon 3 of the WNT3A gene. This variant was found at a very low prevalence (0.35%) in a control population of 443 anonymized subjects and 1.1% in an African population. Conclusion These data suggest that WNT3A does not contribute towards the development of congenital vertebral malformations. Factors such as phenotypic and genetic heterogeneity may underlie our inability to detect mutations in WNT3A in our patient sample. PMID:17888180

  13. Vertebrate pheromones and other semiochemicals: the potential for accommodating complexity in signalling by volatile compounds for vertebrate management

    PubMed Central

    Pickett, John A.; Barasa, Stephen; Birkett, Michael A.

    2014-01-01

    The interaction between volatile and non-volatile, e.g. proteinaceous, components of pheromone and other semiochemical-based signalling systems presents a daunting set of problems for exploitation in the management of vertebrates, good or bad. Aggravating this is the complexity of the mixtures involved with pheromones, not only by definition associated with each species, but also with individual members of that species and their positions within their immediate communities. Nonetheless, already in some contexts, particularly where signals are perceived at other trophic levels from those of the vertebrates, e.g. by arthropods, reductionist approaches can be applied whereby the integrity of complex volatile mixtures is maintained, but perturbed by augmentation with individual components. In the present article, this is illustrated for cattle husbandry, fish farming and human health. So far, crude formulations have been used to imitate volatile semiochemical interactions with non-volatile components, but new approaches must be developed to accommodate more sophisticated interactions and not least the activities of the non-volatile, particularly proteinaceous components, currently being deduced. PMID:25109967

  14. Vertebrate pheromones and other semiochemicals: the potential for accommodating complexity in signalling by volatile compounds for vertebrate management.

    PubMed

    Pickett, John A; Barasa, Stephen; Birkett, Michael A

    2014-08-01

    The interaction between volatile and non-volatile, e.g. proteinaceous, components of pheromone and other semiochemical-based signalling systems presents a daunting set of problems for exploitation in the management of vertebrates, good or bad. Aggravating this is the complexity of the mixtures involved with pheromones, not only by definition associated with each species, but also with individual members of that species and their positions within their immediate communities. Nonetheless, already in some contexts, particularly where signals are perceived at other trophic levels from those of the vertebrates, e.g. by arthropods, reductionist approaches can be applied whereby the integrity of complex volatile mixtures is maintained, but perturbed by augmentation with individual components. In the present article, this is illustrated for cattle husbandry, fish farming and human health. So far, crude formulations have been used to imitate volatile semiochemical interactions with non-volatile components, but new approaches must be developed to accommodate more sophisticated interactions and not least the activities of the non-volatile, particularly proteinaceous components, currently being deduced. PMID:25109967

  15. Absorption Characteristics of Vertebrate Non-Visual Opsin, Opn3

    PubMed Central

    Sugihara, Tomohiro; Nagata, Takashi; Mason, Benjamin; Koyanagi, Mitsumasa; Terakita, Akihisa

    2016-01-01

    Most animals possess multiple opsins which sense light for visual and non-visual functions. Here, we show spectral characteristics of non-visual opsins, vertebrate Opn3s, which are widely distributed among vertebrates. We successfully expressed zebrafish Opn3 in mammalian cultured cells and measured its absorption spectrum spectroscopically. When incubated with 11-cis retinal, zebrafish Opn3 formed a blue-sensitive photopigment with an absorption maximum around 465 nm. The Opn3 converts to an all-trans retinal-bearing photoproduct with an absorption spectrum similar to the dark state following brief blue-light irradiation. The photoproduct experienced a remarkable blue-shift, with changes in position of the isosbestic point, during further irradiation. We then used a cAMP-dependent luciferase reporter assay to investigate light-dependent cAMP responses in cultured cells expressing zebrafish, pufferfish, anole and chicken Opn3. The wild type opsins did not produce responses, but cells expressing chimera mutants (WT Opn3s in which the third intracellular loops were replaced with the third intracellular loop of a Gs-coupled jellyfish opsin) displayed light-dependent changes in cAMP. The results suggest that Opn3 is capable of activating G protein(s) in a light-dependent manner. Finally, we used this assay to measure the relative wavelength-dependent response of cells expressing Opn3 chimeras to multiple quantally-matched stimuli. The inferred spectral sensitivity curve of zebrafish Opn3 accurately matched the measured absorption spectrum. We were unable to estimate the spectral sensitivity curve of mouse or anole Opn3, but, like zebrafish Opn3, the chicken and pufferfish Opn3-JiL3 chimeras also formed blue-sensitive pigments. These findings suggest that vertebrate Opn3s may form blue-sensitive G protein-coupled pigments. Further, we suggest that the method described here, combining a cAMP-dependent luciferase reporter assay with chimeric opsins possessing the third

  16. Fc receptors for immunoglobulins and their appearance during vertebrate evolution.

    PubMed

    Akula, Srinivas; Mohammadamin, Sayran; Hellman, Lars

    2014-01-01

    Receptors interacting with the constant domain of immunoglobulins (Igs) have a number of important functions in vertebrates. They facilitate phagocytosis by opsonization, are key components in antibody-dependent cellular cytotoxicity as well as activating cells to release granules. In mammals, four major types of classical Fc receptors (FcRs) for IgG have been identified, one high-affinity receptor for IgE, one for both IgM and IgA, one for IgM and one for IgA. All of these receptors are related in structure and all of them, except the IgA receptor, are found in primates on chromosome 1, indicating that they originate from a common ancestor by successive gene duplications. The number of Ig isotypes has increased gradually during vertebrate evolution and this increase has likely been accompanied by a similar increase in isotype-specific receptors. To test this hypothesis we have performed a detailed bioinformatics analysis of a panel of vertebrate genomes. The first components to appear are the poly-Ig receptors (PIGRs), receptors similar to the classic FcRs in mammals, so called FcRL receptors, and the FcR γ chain. These molecules are not found in cartilagous fish and may first appear within bony fishes, indicating a major step in Fc receptor evolution at the appearance of bony fish. In contrast, the receptor for IgA is only found in placental mammals, indicating a relatively late appearance. The IgM and IgA/M receptors are first observed in the monotremes, exemplified by the platypus, indicating an appearance during early mammalian evolution. Clearly identifiable classical receptors for IgG and IgE are found only in marsupials and placental mammals, but closely related receptors are found in the platypus, indicating a second major step in Fc receptor evolution during early mammalian evolution, involving the appearance of classical IgG and IgE receptors from FcRL molecules and IgM and IgA/M receptors from PIGR. PMID:24816777

  17. Vascular Plant and Vertebrate Inventory of Tonto National Monument

    USGS Publications Warehouse

    Albrecht, Eric W.; Powell, Brian F.; Halvorson, William L.; Schmidt, Cecilia A.

    2007-01-01

    This report summarizes the results of the first biological inventory of plants and vertebrates at Tonto National Monument (NM). From 2001 to 2003, we surveyed for vascular plants and vertebrates (amphibians, reptiles, birds, and mammals) at Tonto NM to record species presence. We focused most of our efforts along the Cave Springs riparian area, but surveyed other areas as well. We recorded 149 species in the riparian area, and 369 species overall in the monument, including 65 plant species and four bird species that were previously unrecorded for the monument. We recorded 78 plant species in the riparian area that previous studies had not indicated were present there. Several species of each taxonomic group were found only in the riparian area, suggesting that because of their concentration in this small area these populations are vulnerable to disturbance and may be of management concern. Four of the bird species that we recorded (Bell's vireo, yellow warbler, summer tanager, and Abert's towhee) have been identified as riparian 'obligate' species by other sources. Bird species that are obligated to riparian areas are targets of conservation concern due to widespread degradation of riparian areas in the desert southwest over the last century. The flora and fauna of the riparian area would benefit from continued limited public access. The dependence of the riparian area on the spring and surface flow suggests monitoring of this resource per se would benefit management of the riparian area's flora and fauna as well. The monument would benefit from incorporating monitoring protocols developed by the Sonoran Desert Network Inventory and Monitoring program rather than initiating a separate program for the riparian area. Park managers can encourage the Inventory and Monitoring program to address the unique monitoring challenges presented by small spatial areas such as this riparian area, and can request specific monitoring recommendations. We suggest that repeat

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

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

  19. Parametric modelling and segmentation of vertebral bodies in 3D CT and MR spine images

    NASA Astrophysics Data System (ADS)

    Štern, Darko; Likar, Boštjan; Pernuš, Franjo; Vrtovec, Tomaž

    2011-12-01

    Accurate and objective evaluation of vertebral deformations is of significant importance in clinical diagnostics and therapy of pathological conditions affecting the spine. Although modern clinical practice is focused on three-dimensional (3D) computed tomography (CT) and magnetic resonance (MR) imaging techniques, the established methods for evaluation of vertebral deformations are limited to measuring deformations in two-dimensional (2D) x-ray images. In this paper, we propose a method for quantitative description of vertebral body deformations by efficient modelling and segmentation of vertebral bodies in 3D. The deformations are evaluated from the parameters of a 3D superquadric model, which is initialized as an elliptical cylinder and then gradually deformed by introducing transformations that yield a more detailed representation of the vertebral body shape. After modelling the vertebral body shape with 25 clinically meaningful parameters and the vertebral body pose with six rigid body parameters, the 3D model is aligned to the observed vertebral body in the 3D image. The performance of the method was evaluated on 75 vertebrae from CT and 75 vertebrae from T2-weighted MR spine images, extracted from the thoracolumbar part of normal and pathological spines. The results show that the proposed method can be used for 3D segmentation of vertebral bodies in CT and MR images, as the proposed 3D model is able to describe both normal and pathological vertebral body deformations. The method may therefore be used for initialization of whole vertebra segmentation or for quantitative measurement of vertebral body deformations.

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

    PubMed

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

    2014-02-01

    In most bony fishes vertebral column strain during locomotion is almost exclusively in the intervertebral joints, and when these joints move there is the potential to store and release strain energy. Since cartilaginous fishes have poorly mineralized vertebral centra, we tested whether the vertebral bodies undergo substantial strain and thus may be sites of energy storage during locomotion. We measured axial strains of the intervertebral joints and vertebrae in vivo and ex vivo to characterize the dynamic behavior of the vertebral column. We used sonomicrometry to directly measure in vivo and in situ strains of intervertebral joints and vertebrae of Squalus acanthias swimming in a flume. For ex vivo measurements, we used a materials testing system to dynamically bend segments of vertebral column at frequencies ranging from 0.25 to 1.00 Hz and a range of physiologically relevant curvatures, which were determined using a kinematic analysis. The vertebral centra of S. acanthias undergo strain during in vivo volitional movements as well as in situ passive movements. Moreover, when isolated segments of vertebral column were tested during mechanical bending, we measured the same magnitudes of strain. These data support our hypothesis that vertebral column strain in lateral bending is not limited to the intervertebral joints. In histological sections, we found that the vertebral column of S. acanthias has an intracentral canal that is open and covered with a velum layer. An open intracentral canal may indicate that the centra are acting as tunics around some sections of a hydrostat, effectively stiffening the vertebral column. These data suggest that the entire vertebral column of sharks, both joints and centra, is mechanically engaged as a dynamic spring during locomotion. PMID:24388493

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

    PubMed Central

    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

  2. Initial clinical experience with a novel vertebral augmentation system for treatment of symptomatic vertebral compression fractures: A case series of 26 consecutive patients

    PubMed Central

    2011-01-01

    Background Minimally invasive vertebral augmentation procedures are widely used to treat vertebral compression fractures although procedural polymethylmethacrylate cement leakage remains common. We report herein our initial experience with a novel vertebral augmentation technique designed to treat symptomatic vertebral osteoporotic fractures and osteolytic metastases with minimal cement extravasation. Methods Forty-two vertebral fractures were identified in 26 consecutive patients (mean age 74 ± 9 years). All patients were treated with a novel percutaneous vertebral augmentation device (Kiva® VCF Treatment System, Benvenue Medical, Santa Clara, CA, USA). Indications for surgery included recent (≤ 3 months) symptomatic osteoporotic vertebral fracture (n = 34) and pathologic vertebral fractures (e.g. metabolic bone disease, myeloma, metastasis) (n = 8) located between T10 and S1. Patient outcomes were evaluated pre-treatment and at 2- and 6-month follow-up visits. Postoperative cement extravasation was assessed with computed tomography. Patient-reported back pain was quantified using an 11-point numeric scale. Back-specific functional disability was self-reported with the Oswestry Disability Index on a 0 to 100% scale. Results No cases of intraoperative hypotension, respiratory disturbance, neurological deterioration, infection, or death were observed. There were 2 (4.8%) levels where anterior cement leakage was visible radiographically in patients with osteolyses. No intracanal leakage was observed. Back pain scores improved 71% (p < 0.001) from pre-treatment to the 6-month follow-up. Back function improved 56% from baseline to 6 months (p < 0.001). Conclusions The initial clinical experience with the Kiva® System demonstrated significant improvements in back pain and function with minimal and clinically insignificant procedural cement leakage. PMID:21939548

  3. Evolution of the head-trunk interface in tetrapod vertebrates.

    PubMed

    Sefton, Elizabeth M; Bhullar, Bhart-Anjan S; Mohaddes, Zahra; Hanken, James

    2016-01-01

    Vertebrate neck musculature spans the transition zone between head and trunk. The extent to which the cucullaris muscle is a cranial muscle allied with the gill levators of anamniotes or is instead a trunk muscle is an ongoing debate. Novel computed tomography datasets reveal broad conservation of the cucullaris in gnathostomes, including coelacanth and caecilian, two sarcopterygians previously thought to lack it. In chicken, lateral plate mesoderm (LPM) adjacent to occipital somites is a recently identified embryonic source of cervical musculature. We fate-map this mesoderm in the axolotl (Ambystoma mexicanum), which retains external gills, and demonstrate its contribution to posterior gill-levator muscles and the cucullaris. Accordingly, LPM adjacent to the occipital somites should be regarded as posterior cranial mesoderm. The axial position of the head-trunk border in axolotl is congruent between LPM and somitic mesoderm, unlike in chicken and possibly other amniotes. PMID:27090084

  4. PAR-1 phosphorylates Mind bomb to promote vertebrate neurogenesis

    PubMed Central

    Ossipova, Olga; Ezan, Jerome; Sokol, Sergei Y.

    2010-01-01

    Summary Generation of neurons in the vertebrate central nervous system requires complex transcriptional regulatory network and signaling processes in polarized neuroepithelial progenitor cells. Here we demonstrate that neurogenesis in the Xenopus neural plate in vivo and mammalian neural progenitors in vitro involves intrinsic antagonistic activities of the polarity proteins PAR-1 and aPKC. Furthermore, we show that Mind bomb (Mib), a ubiquitin ligase that promotes Notch ligand trafficking and activity, is a crucial molecular substrate for PAR-1. The phosphorylation of Mib by PAR-1 results in Mib degradation, repression of Notch signaling and stimulation of neuronal differentiation. These observations suggest a conserved mechanism for neuronal fate determination that might operate during asymmetric divisions of polarized neural progenitor cells. PMID:19686683

  5. Spinal corollary discharge modulates motion sensing during vertebrate locomotion

    PubMed Central

    Chagnaud, Boris P.; Banchi, Roberto; Simmers, John; Straka, Hans

    2015-01-01

    During active movements, neural replicas of the underlying motor commands may assist in adapting motion-detecting sensory systems to an animal's own behaviour. The transmission of such motor efference copies to the mechanosensory periphery offers a potential predictive substrate for diminishing sensory responsiveness to self-motion during vertebrate locomotion. Here, using semi-isolated in vitro preparations of larval Xenopus, we demonstrate that shared efferent neural pathways to hair cells of vestibular endorgans and lateral line neuromasts express cyclic impulse bursts during swimming that are directly driven by spinal locomotor circuitry. Despite common efferent innervation and discharge patterns, afferent signal encoding at the two mechanosensory peripheries is influenced differentially by efference copy signals, reflecting the different organization of body/water motion-detecting processes in the vestibular and lateral line systems. The resultant overall gain reduction in sensory signal encoding in both cases, which likely prevents overstimulation, constitutes an adjustment to increased stimulus magnitudes during locomotion. PMID:26337184

  6. Vertebrate-like regeneration in the invertebrate chordate amphioxus

    PubMed Central

    Somorjai, Ildikó M. L.; Garcia-Fernàndez, Jordi; Escrivà, Hector

    2012-01-01

    An important question in biology is why some animals are able to regenerate, whereas others are not. The basal chordate amphioxus is uniquely positioned to address the evolution of regeneration. We report here the high regeneration potential of the European amphioxus Branchiostoma lanceolatum. Adults regenerate both anterior and posterior structures, including neural tube, notochord, fin, and muscle. Development of a classifier based on tail regeneration profiles predicts the assignment of young and old adults to their own class with >94% accuracy. The process involves loss of differentiated characteristics, formation of an msx-expressing blastema, and neurogenesis. Moreover, regeneration is linked to the activation of satellite-like Pax3/7 progenitor cells, the extent of which declines with size and age. Our results provide a framework for understanding the evolution and diversity of regeneration mechanisms in vertebrates. PMID:22203957

  7. Origins of the Vertebrate Erythro/Megakaryocytic System

    PubMed Central

    Svoboda, Ondrej; Bartunek, Petr

    2015-01-01

    Vertebrate erythrocytes and thrombocytes arise from the common bipotent thrombocytic-erythroid progenitors (TEPs). Even though nonmammalian erythrocytes and thrombocytes are phenotypically very similar to each other, mammalian species have developed some key evolutionary improvements in the process of erythroid and thrombocytic differentiation, such as erythroid enucleation, megakaryocyte endoreduplication, and platelet formation. This brings up a few questions that we try to address in this review. Specifically, we describe the ontology of erythro-thrombopoiesis during adult hematopoiesis with focus on the phylogenetic origin of mammalian erythrocytes and thrombocytes (also termed platelets). Although the evolutionary relationship between mammalian and nonmammalian erythroid cells is clear, the appearance of mammalian megakaryocytes is less so. Here, we discuss recent data indicating that nonmammalian thrombocytes and megakaryocytes are homologs. Finally, we hypothesize that erythroid and thrombocytic differentiation evolved from a single ancestral lineage, which would explain the striking similarities between these cells. PMID:26557683

  8. Human Disc Nucleus Properties and Vertebral Endplate Permeability

    PubMed Central

    Rodriguez, Azucena G.; Slichter, Chloe K.; Acosta, Frank L.; Rodriguez-Soto, Ana E.; Burghardt, Andrew J.; Majumdar, Sharmila; Lotz, Jeffrey C.

    2010-01-01

    Study of human cadaveric discs quantifying endplate permeability and porosity and correlating these with measures of disc quality: cell density, proteoglycan content, and overall degeneration. Permeability and porosity increased with age and were not correlated with cell density or overall degeneration, suggesting that endplate calcification may not accelerate disc degeneration. Study Design Experimental quantification of relationships between vertebral endplate morphology, permeability, disc cell density, glycosaminoglycan content and degeneration in samples harvested from human cadaveric spines. Objective To test the hypothesis that variation in endplate permeability and porosity contribute to changes in intervertebral disc cell density and overall degeneration. Summary of Background Data Cells within the intervertebral disc are dependent on diffusive exchange with capillaries in the adjacent vertebral bone. Previous findings suggest that blocked routes of transport negatively affect disc quality, yet there are no quantitative relationships between human vertebral endplate permeability, porosity, cell density and disc degeneration. Such relationships would be valuable for clarifying degeneration risk factors, and patient features that may impede efforts at disc tissue engineering. Methods Fifty-one motion segments were harvested from 13 frozen cadaveric human lumbar spines (32 to 85 years) and classified for degeneration using the MRI-based Pfirrmann scale. A cylindrical core was harvested from the center of each motion segment that included vertebral bony and cartilage endplates along with adjacent nucleus tissue. The endplate mobility, a type of permeability, was measured directly using a custom-made permeameter before and after the cartilage endplate was removed. Cell density within the nucleus tissue was estimated using the picogreen method while the nuclear GAG content was quantified using the DMMB technique. Specimens were imaged at 8 μm resolution using

  9. A Calcium-Relay Mechanism in Vertebrate Phototransduction

    PubMed Central

    2013-01-01

    Calcium-signaling in cells requires a fine-tuned system of calcium-transport proteins involving ion channels, exchangers, and ion-pumps but also calcium-sensor proteins and their targets. Thus, control of physiological responses very often depends on incremental changes of the cytoplasmic calcium concentration, which are sensed by calcium-binding proteins and are further transmitted to specific target proteins. This Review will focus on calcium-signaling in vertebrate photoreceptor cells, where recent physiological and biochemical data indicate that a subset of neuronal calcium sensor proteins named guanylate cyclase-activating proteins (GCAPs) operate in a calcium-relay system, namely, to make gradual responses to small changes in calcium. We will further integrate this mechanism in an existing computational model of phototransduction showing that it is consistent and compatible with the dynamics that are characteristic for the precise operation of the phototransduction pathways. PMID:23472635

  10. Ludwig Edinger: the vertebrate series and comparative neuroanatomy.

    PubMed

    Patton, Paul

    2015-01-01

    At the end of the nineteenth century, Ludwig Edinger completed the first comparative survey of the microscopic anatomy of vertebrate brains. He is regarded as the founder of the field of comparative neuroanatomy. Modern commentators have misunderstood him to have espoused an anti-Darwinian linear view of brain evolution, harkening to the metaphysics of the scala naturae. This understanding arises, in part, from an increasingly contested view of nineteenth-century morphology in Germany. Edinger did espouse a progressionist, though not strictly linear, view of forebrain evolution, but his work also provided carefully documented evidence that brain stem structures vary in complexity independently from one another and across species in a manner that is not compatible with linear progress. This led Edinger to reject progressionism for all brain structures other than the forebrain roof, based on reasoning not too dissimilar from those his successors used to dismiss it for the forebrain roof. PMID:25187404

  11. Spatial Distribution of Intraflagellar Transport Proteins in Vertebrate Photoreceptors

    PubMed Central

    Luby-Phelps, Katharine; Fogerty, Joseph; Baker, Sheila A.; Pazour, Gregory J.; Besharse, Joseph C.

    2008-01-01

    Intraflagellar transport (IFT) of a ∼17S particle containing at least 16 distinct polypeptides is required for the assembly and maintenance of cilia and flagella. Although both genetic and biochemical evidence suggest a role for IFT in vertebrate photoreceptors, the spatial distribution of IFT proteins within photoreceptors remains poorly defined. We have evaluated the distribution of 4 IFT proteins using a combination of immunocytochemistry and rod-specific over-expression of GFP tagged IFT proteins. Endogenous IFT proteins are most highly concentrated within the inner segment, around the basal body, and within the outer segment IFT proteins are localized in discrete particles along the entire length of the axoneme. IFT52-GFP and IFT57-GFP mimicked this pattern in transgenic Xenopus. PMID:17931679

  12. The cellular and molecular mechanisms of vertebrate lens development

    PubMed Central

    Cvekl, Aleš; Ashery-Padan, Ruth

    2014-01-01

    The ocular lens is a model system for understanding important aspects of embryonic development, such as cell specification and the spatiotemporally controlled formation of a three-dimensional structure. The lens, which is characterized by transparency, refraction and elasticity, is composed of a bulk mass of fiber cells attached to a sheet of lens epithelium. Although lens induction has been studied for over 100 years, recent findings have revealed a myriad of extracellular signaling pathways and gene regulatory networks, integrated and executed by the transcription factor Pax6, that are required for lens formation in vertebrates. This Review summarizes recent progress in the field, emphasizing the interplay between the diverse regulatory mechanisms employed to form lens progenitor and precursor cells and highlighting novel opportunities to fill gaps in our understanding of lens tissue morphogenesis. PMID:25406393

  13. [Molecular physiology of glycine receptors in nervous system of vertebrates].

    PubMed

    2014-03-01

    Glycine receptor is the anion-selective channel, providing fast synaptic transmission in the central nervous system of vertebrates. Together with the nicotinic acetylcholine, GABA and serotonin (5-HT3R) receptors, it belongs to the superfamily of pentameric cys-loop receptors. It has been cloned one beta and four alpha subunits of glycine receptor, which are specifically distributed in different areas of the nervous system. Due to their specific molecular properties and distribution, different subunits ensure important physiological functions: from control of motor activity and regulation of neuronal differentiation to sensory information processing and modulation of pain sensitivity. In this review we briefly describe main functions of these transmembrane proteins, their distribution and molecular architecture. Special attention is paid to recent studies on the molecular physiology of these receptors, as well as on presenting of molecular domains responsible for their modulation and dysfunction. PMID:25508361

  14. [Molecular physiology of glycine receptors in nervous system of vertebrates].

    PubMed

    Maleeva, G V; Brezhestovskiĭ, P D

    2014-03-01

    Glycine receptor is the anion-selective channel, providing fast synaptic transmission in the central nervous system of vertebrates. Together with the nicotinic acetylcholine, GABA and serotonin (5-HT3R) receptors, it belongs to the superfamily of pentameric cys-loop receptors. It has been cloned one beta and four alpha subunits of glycine receptor, which are specifically distributed in different areas of the nervous system. Due to their specific molecular properties and distribution, different subunits ensure important physiological functions: from control of motor activity and regulation of neuronal differentiation to sensory information processing and modulation of pain sensitivity. In this review we briefly describe main functions of these transmembrane proteins, their distribution and molecular architecture. Special attention is paid to recent studies on the molecular physiology of these receptors, as well as on presenting of molecular domains responsible for their modulation and dysfunction. PMID:25464730

  15. Differential diagnosis of multiple vertebral compression: butterfly vertebrae

    PubMed Central

    Ozaras, Nihal; Gumussu, Kevser; Demir, Saliha Eroglu; Rezvani, Aylin

    2015-01-01

    [Purpose] A butterfly vertebra is a rare congenital anomaly resulting from a symmetric fusion defect. Only a few cases of butterfly vertebra have been described. This anomaly may be isolated or associated with Pfeiffer, Jarcho-Levins, Crouzon, or Alagille syndrome. [Subject and Methods] We herein describe a 38-year-old man who presented with neck and low back pain and was found to have butterfly vertebrae at the T9 and L3 levels. He also had Behçet’s disease and psoriasis. [Results] The patient’s symptoms improved with analgesics and physiotherapy. [Conclusion] To our knowledge, butterfly vertebrae at two levels have never been reported. Butterfly vertebrae may be confused with vertebral fractures in lateral radiographs, and awareness of this anomaly is important for a correct diagnosis. PMID:26696746

  16. Cranio-vertebral junction anomaly: atlanto-occipital assimilation.

    PubMed

    Pooja Jain, -; Khursheed Raza, -; Chiman Kumari, -; Manisha Hansda, -; Sb Ray, -

    2016-01-01

    Cranio-vertebral junction is a pivot which holds the globe of the head. Bony anomalies at this point are particularly significant because they lodge the spinal cord and lower part of the brain stem. Clinically fusion of the atlas with the lower part of the occiput is known as Atlanto-occipital assimilation or atlas occipitalization, which can be either partial or complete depending upon the extent of fusion. It can present as totally asymptomatic accidental finding or can be a cause behind major neuro-vascular compression. The present case study is an endeavor to explain occipitalization of atlas bone on the basis of embryology and explain its clinical relevance. PMID:27424507

  17. Noise regulation and symmetry breaking during vertebrate body elongation

    NASA Astrophysics Data System (ADS)

    Emonet, Thierry; Das, Dipjyoti; Holley, Scott A.

    Elongation of the vertebrate body axis is driven by collective cell migration and cell proliferation at the posteriorly advancing embryonic tailbud. Within the Zebrafish tailbud an ordered stream of cells symmetrically bifurcates to form the left and right halves of the presomitic mesoderm. Maintaining bilateral symmetry during this process is critical to avoid catastrophic spine deformation. Using direct comparison between experimental data and a simple model of cell migration we identified the dynamic regulation of the noise in the direction of motion of individual cells as a critical factor in maintaining symmetric cell flow. Genetic perturbations that reduced noise led to body axis deformation whereas an increase in noise led to retarded elongation as predicted by our model.

  18. Bio-logging of physiological parameters in higher marine vertebrates

    NASA Astrophysics Data System (ADS)

    Ponganis, Paul J.

    2007-02-01

    Bio-logging of physiological parameters in higher marine vertebrates had its origins in the field of bio-telemetry in the 1960s and 1970s. The development of microprocessor technology allowed its first application to bio-logging investigations of Weddell seal diving physiology in the early 1980s. Since that time, with the use of increased memory capacity, new sensor technology, and novel data processing techniques, investigators have examined heart rate, temperature, swim speed, stroke frequency, stomach function (gastric pH and motility), heat flux, muscle oxygenation, respiratory rate, diving air volume, and oxygen partial pressure (P) during diving. Swim speed, heart rate, and body temperature have been the most commonly studied parameters. Bio-logging investigation of pressure effects has only been conducted with the use of blood samplers and nitrogen analyses on animals diving at isolated dive holes. The advantages/disadvantages and limitations of recording techniques, probe placement, calibration techniques, and study conditions are reviewed.

  19. Vascular endothelial growth factors: A comparison between invertebrates and vertebrates.

    PubMed

    Kipryushina, Yulia O; Yakovlev, Konstantin V; Odintsova, Nelly A

    2015-12-01

    This review aims to summarize recent data concerning the structure and role of the members of the vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) families in the context of early development, organogenesis and regeneration, with a particular emphasis on the role of these factors in the development of invertebrates. Homologs of VEGF and/or VEGFR have been found in all Eumetazoa, in both Radiata and Bilateria, where they are expressed in the descendants of different germ layers and play a pivotal role in the development of animals with and without a vascular system. VEGF is a well-known angiogenesis regulator, but this factor also control cell migration during neurogenesis and the development of branching organs (the trachea) in invertebrate and vertebrate species. A possible explanation for the origin of Vegf/Vegfr in the animal kingdom and a pathway of Vegf/Vegfr evolution are discussed. PMID:26066416

  20. Vertebral anomaly in fossil sea cows (Mammalia, Sirenia).

    PubMed

    Voss, Manja; Asbach, Patrick; Hilger, André

    2011-06-01

    Four incompletely preserved caudal vertebrae lacking the neural arches of two fossil sirenian individuals of Halitherium schinzii (Oligocene) from the Rhine area in Germany and northern Belgium reveal osteological alterations. The caudal vertebrae possess a transverse process with growth retardation. This asymmetry indicates that the affected transverse processes are less developed than their counterparts and, consequently, deviate from the norm. Computed tomography (CT) scans reveal osteosclerotic patterns, a morphological feature that characterizes sea cows and supports the nonpathological state of the vertebrae. Additionally, no indications of vertebral fractures or any other occurrences due to external factors are present. This is the oldest documentation of such an anomaly in any sirenian and is interpreted here as hypoplasia, the underdevelopment of an organ or parts of it that might cause a functional deficiency. PMID:21538937

  1. Histone H1 null vertebrate cells exhibit altered nucleosome architecture

    PubMed Central

    Hashimoto, Hideharu; Takami, Yasunari; Sonoda, Eiichiro; Iwasaki, Tomohito; Iwano, Hidetomo; Tachibana, Makoto; Takeda, Shunichi; Nakayama, Tatsuo; Kimura, Hiroshi; Shinkai, Yoichi

    2010-01-01

    In eukaryotic nuclei, DNA is wrapped around an octamer of core histones to form nucleosomes, and chromatin fibers are thought to be stabilized by linker histones of the H1 type. Higher eukaryotes express multiple variants of histone H1; chickens possess six H1 variants. Here, we generated and analyzed the phenotype of a complete deletion of histone H1 genes in chicken cells. The H1-null cells showed decreased global nucleosome spacing, expanded nuclear volumes, and increased chromosome aberration rates, although proper mitotic chromatin structure appeared to be maintained. Expression array analysis revealed that the transcription of multiple genes was affected and was mostly downregulated in histone H1-deficient cells. This report describes the first histone H1 complete knockout cells in vertebrates and suggests that linker histone H1, while not required for mitotic chromatin condensation, plays important roles in nucleosome spacing and interphase chromatin compaction and acts as a global transcription regulator. PMID:20156997

  2. An Overview of Seasonal Changes in Oxidative Stress and Antioxidant Defence Parameters in Some Invertebrate and Vertebrate Species

    PubMed Central

    Chainy, Gagan Bihari Nityananda; Paital, Biswaranjan; Dandapat, Jagneswar

    2016-01-01

    Antioxidant defence system, a highly conserved biochemical mechanism, protects organisms from harmful effects of reactive oxygen species (ROS), a by-product of metabolism. Both invertebrates and vertebrates are unable to modify environmental physical factors such as photoperiod, temperature, salinity, humidity, oxygen content, and food availability as per their requirement. Therefore, they have evolved mechanisms to modulate their metabolic pathways to cope their physiology with changing environmental challenges for survival. Antioxidant defences are one of such biochemical mechanisms. At low concentration, ROS regulates several physiological processes, whereas at higher concentration they are toxic to organisms because they impair cellular functions by oxidizing biomolecules. Seasonal changes in antioxidant defences make species able to maintain their correct ROS titre to take various physiological functions such as hibernation, aestivation, migration, and reproduction against changing environmental physical parameters. In this paper, we have compiled information available in the literature on seasonal variation in antioxidant defence system in various species of invertebrates and vertebrates. The primary objective was to understand the relationship between varied biological phenomena seen in different animal species and conserved antioxidant defence system with respect to seasons. PMID:27127682

  3. An Overview of Seasonal Changes in Oxidative Stress and Antioxidant Defence Parameters in Some Invertebrate and Vertebrate Species.

    PubMed

    Chainy, Gagan Bihari Nityananda; Paital, Biswaranjan; Dandapat, Jagneswar

    2016-01-01

    Antioxidant defence system, a highly conserved biochemical mechanism, protects organisms from harmful effects of reactive oxygen species (ROS), a by-product of metabolism. Both invertebrates and vertebrates are unable to modify environmental physical factors such as photoperiod, temperature, salinity, humidity, oxygen content, and food availability as per their requirement. Therefore, they have evolved mechanisms to modulate their metabolic pathways to cope their physiology with changing environmental challenges for survival. Antioxidant defences are one of such biochemical mechanisms. At low concentration, ROS regulates several physiological processes, whereas at higher concentration they are toxic to organisms because they impair cellular functions by oxidizing biomolecules. Seasonal changes in antioxidant defences make species able to maintain their correct ROS titre to take various physiological functions such as hibernation, aestivation, migration, and reproduction against changing environmental physical parameters. In this paper, we have compiled information available in the literature on seasonal variation in antioxidant defence system in various species of invertebrates and vertebrates. The primary objective was to understand the relationship between varied biological phenomena seen in different animal species and conserved antioxidant defence system with respect to seasons. PMID:27127682

  4. Was the appearance of surfactants in air breathing vertebrates ultimately the cause of decompression sickness and autoimmune disease?

    PubMed

    Arieli, Ran

    2015-01-15

    All air breathing vertebrates are endowed with pulmonary surfactants, surface-active lipoprotein complexes formed by type II alveolar cells. Surfactants are deposited in clearly defined areas on the luminal aspect of blood vessels, producing hydrophobic spots. Gas nanobubbles measuring 5-100nm form spontaneously on the smooth hydrophobic spot from dissolved gas. Bubbles nucleate and grow at these spots after decompression from high pressure. Proteins with hydrophobic regions circulating in the blood will adhere to the gas phase-plasma interface. Deformation of their secondary and tertiary configuration will present them as foreign molecules or autoantigens. Components of the intact protein which are also present in a deformed protein may be recognized as foreign too. This process is proposed as the trigger for autoimmune diseases. The presence of autoimmune disease in air breathing vertebrates, increased autoimmunity and the elevated risk of decompression sickness with age, as well as variable sensitivity to both diseases, can be matched with the appearance of surfactant spots. Eliminating these spots may provide protection against both diseases. PMID:25462836

  5. 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

  6. Streptococcal vertebral osteomyelitis: multiple faces of the same disease.

    PubMed

    Murillo, O; Roset, A; Sobrino, B; Lora-Tamayo, J; Verdaguer, R; Jiménez-Mejias, E; Nolla, J M; Colmenero, J de D; Ariza, J

    2014-01-01

    The role of Streptococcus species as an aetiological microorganism of vertebral osteomyelitis (VO) is considered to be of little relevance. We aimed to describe a large number of cases of streptococcal vertebral osteomyelitis (SVO), to analyze the clinical features associated with different Streptococcus species, and to compare them with a cohort of patients with VO caused by Staphylococcus aureus. An incidence study and a retrospective, multicenter, observational clinical study of cases of SVO (1991-2011) were performed. Statistical comparison of SVO by different species and between them and staphylococcal VO was carried out. Over the whole period there was an increasing incidence in the number of VOs and SVOs per year (p <0.05). Among 58 cases of SVO, those caused by non-viridans streptococcus (Streptococcus pneumoniae, Streptococcus agalactiae and Streptococcus pyogenes; n = 26) mimicked VO by S. aureus, and presented with more fever, neurological symptoms and paravertebral abscesses in comparison with those caused by the viridans group (remaining species). In contrast, the latter have a sub-acute clinical picture and were associated with the presence of endocarditis (p <0.05). Among non-viridans SVOs, concomitant infection was specifically related to S. pneumoniae (p <0.05). In conclusion, SVO presents a wide range of clinical patterns. The relationship between VO and diagnosis of endocarditis was established with SVO caused by the viridans group. Whereas non-viridans SVO mimics acute characteristics of VO caused by S. aureus, cases of viridans SVO are significantly more likely to have a sub-acute clinical presentation. The increased incidence of SVO during the last decades could support a new epidemiological scenario. PMID:23889700

  7. Shedding light into the function of the earliest vertebrate skeleton

    NASA Astrophysics Data System (ADS)

    Martinez-Perez, Carlos; Purnell, Mark; Rayfield, Emily; Donoghue, Philip

    2016-04-01

    Conodonts are an extinct group of jawless vertebrates, the first in our evolutionary lineage to develop a biomineralized skeleton. As such, the conodont skeleton is of great significance because of the insights it provides concerning the biology and function of the primitive vertebrate skeleton. Conodont function has been debated for a century and a half on the basis of its paleocological importance in the Palaezoic ecosystems. However, due to the lack of extanct close representatives and the small size of the conodont element (under a milimiter in length) strongly limited their functional analysis, traditional restricted to analogy. More recently, qualitative approaches have been developed, facilitating tests of element function based on occlusal performance and analysis of microwear and microstructure. In this work we extend these approaches using novel quantitative experimental methods including Synchrotron Radiation X-ray Tomographic Microscopy or Finite Element Analysis to test hypotheses of conodont function. The development of high resolution virtual models of conodont elements, together with biomechanical approaches using Finite Element analysis, informed by occlusal and microwear analyses, provided conclusive support to test hypothesis of structural adaptation within the crown tissue microstructure, showing a close topological co-variation patterns of compressive and tensile stress distribution with different crystallite orientation. In addition, our computational analyses strongly support a tooth-like function for many conodont species. Above all, our study establishes a framework (experimental approach) in which the functional ecology of conodonts can be read from their rich taxonomy and phylogeny, representing an important attempt to understand the role of this abundant and diverse clade in the Phanerozoic marine ecosystems.

  8. Management strategy for bilateral complex vertebral artery aneurysms.

    PubMed

    Saito, Norihiro; Kamiyama, Hiroyasu; Takizawa, Katsumi; Takebayashi, Seiji; Asano, Takeshi; Kobayashi, Tohru; Kobayashi, Rina; Kubota, Shunsuke; Ito, Yasuhiro; Karagiozov, Kostadin L

    2016-04-01

    Bilateral complex vertebral artery aneurysms (BCoVAAns) have no established strategy of management. We retrospectively reviewed five consecutive patients with unruptured BCoVAAns between January 2006 and December 2012. Considering surgical risks of lower cranial nerve (LCN) injuries and eventual growth of an opposite side lesion after unilateral vertebral artery (VA) occlusion, we proposed a strategy of combined open and interventional treatment using revascularization. We applied the following several specific techniques: (1) proximal clipping and occipital artery-posterior inferior cerebellar artery (OA-PICA) and/or superficial temporary artery (STA)-superior cerebellar artery (SCA) bypasses; (2) Distal blood pressure, motor evoked potentials (MEPs), and somatosensory evoked potentials (SEPs) monitoring after parent artery temporary occlusion for safe permanent occlusion of the proximal portions of VA and PICA; (3) V3 to V4 bypass using radial artery (RA) graft with proximal clipping or trapping, two of them combined with OA-PICA bypass; (4) VA fenestration as an opportunity to preserve the flow of the parent artery. Two patients were treated bilaterally and 3 unilaterally, with modified Rankin scale assessed at 39 months postoperatively in average 0 in 2, 1 in 2, and 2 in 1, respectively, and the untreated opposite side lesions without regrowth or bleeding. Two patients with patent V3-RA-V4 bypass complained of dysphagia due to LCN palsies. One of them however suffered a cerebellar infarction due to occlusion of the OA-PICA bypass. When BCoVAAns require surgical treatment, revascularization or preservation of the VA should be considered at the first operation. By doing so, the opposite aneurysm can be effectively occluded by coil embolization, even with VA sacrifice if required. PMID:26564148

  9. Oxygen in demand: How oxygen has shaped vertebrate physiology.

    PubMed

    Dzal, Yvonne A; Jenkin, Sarah E M; Lague, Sabine L; Reichert, Michelle N; York, Julia M; Pamenter, Matthew E

    2015-08-01

    In response to varying environmental and physiological challenges, vertebrates have evolved complex and often overlapping systems. These systems detect changes in environmental oxygen availability and respond by increasing oxygen supply to the tissues and/or by decreasing oxygen demand at the cellular level. This suite of responses is termed the oxygen transport cascade and is comprised of several components. These components include 1) chemosensory detectors that sense changes in oxygen, carbon dioxide, and pH in the blood, and initiate changes in 2) ventilation and 3) cardiac work, thereby altering the rate of oxygen delivery to, and carbon dioxide clearance from, the tissues. In addition, changes in 4) cellular and systemic metabolism alters tissue-level metabolic demand. Thus the need for oxygen can be managed locally when increasing oxygen supply is not sufficient or possible. Together, these mechanisms provide a spectrum of responses that facilitate the maintenance of systemic oxygen homeostasis in the face of environmental hypoxia or physiological oxygen depletion (i.e. due to exercise or disease). Bill Milsom has dedicated his career to the study of these responses across phylogenies, repeatedly demonstrating the power of applying the comparative approach to physiological questions. The focus of this review is to discuss the anatomy, signalling pathways, and mechanics of each step of the oxygen transport cascade from the perspective of a Milsomite. That is, by taking into account the developmental, physiological, and evolutionary components of questions related to oxygen transport. We also highlight examples of some of the remarkable species that have captured Bill's attention through their unique adaptations in multiple components of the oxygen transport cascade, which allow them to achieve astounding physiological feats. Bill's research examining the oxygen transport cascade has provided important insight and leadership to the study of the diverse suite

  10. Novel Hepatozoon in vertebrates from the southern United States.

    PubMed

    Allen, Kelly E; Yabsley, Michael J; Johnson, Eileen M; Reichard, Mason V; Panciera, Roger J; Ewing, Sidney A; Little, Susan E

    2011-08-01

    Novel Hepatozoon spp. sequences collected from previously unrecognized vertebrate hosts in North America were compared with documented Hepatozoon 18S rRNA sequences in an effort to examine phylogenetic relationships between the different Hepatozoon organisms found cycling in nature. An approximately 500-base pair fragment of 18S rDNA common to Hepatozoon spp. and some other apicomplexans was amplified and sequenced from the tissues or blood of 16 vertebrate host species from the southern United States, including 1 opossum (Didelphis virginiana), 2 bobcats (Lynx rufus), 1 domestic cat (Felis catus), 3 coyotes (Canis latrans), 1 gray fox (Urocyon cinereoargenteus), 4 raccoons (Procyon lotor), 1 pet boa constrictor (Boa constrictor imperator), 1 swamp rabbit (Sylvilagus aquaticus), 1 cottontail rabbit (Sylvilagus floridanus), 4 woodrats (Neotoma fuscipes and Neotoma micropus), 3 white-footed mice (Peromyscus leucopus), 8 cotton rats (Sigmodon hispidus), 1 cotton mouse (Peromyscus gossypinus), 1 eastern grey squirrel (Sciurus carolinensis), and 1 woodchuck (Marmota monax). Phylogenetic analyses and comparison with sequences in the existing database revealed distinct groups of Hepatozoon spp., with clusters formed by sequences obtained from scavengers and carnivores (opossum, raccoons, canids, and felids) and those obtained from rodents. Surprisingly, Hepatozoon spp. sequences from wild rabbits were most closely related to sequences obtained from carnivores (97.2% identical), and the sequence from the boa constrictor was most closely related to the rodent cluster (97.4% identical). These data are consistent with recent work identifying prey-predator transmission cycles in Hepatozoon spp. and suggest this pattern may be more common than previously recognized. PMID:21506825

  11. 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

  12. Vertebrate biochronology of late Triassic red beds in New Mexico

    SciTech Connect

    Hunt, A.P. )

    1989-09-01

    Four vertebrate biochrons can be recognized in Late Triassic strata of New Mexico: (A) Metoposaurus-Rutiodon-Desmatosuchus-Calyptosuchus-Placerias occurs in the Los Esteros member of the Santa Rosa formation near Lamy and is less well known from the lower Petrified Forest Member of the Chinle Formation near San Ysidro, at Mesa del Oro, near Fort Wingate, at Ojo Huelos, and in the Joyita hills. (B) Anaschisma-Belodon-Typothorax-Desmatosuchus-Paratypothorax occurs in the lower Bull Canyon formation in Bull Canyon and near Tucumcari, in the Trujillo Formation near Tucumcari, and possibly in the Travesser Formation of the Dry Cimarron valley, the Petrified Forest Member near Carthage, and the Garita Creek formation near Lamy and Conchas Lake. (C) Anaschisma-Belodon-Typothorax occurs in the upper Bull Canyon formation in Bull Canyon, in the upper Petrified Forest Member near San Ysidro, at Ghost Ranch, near Albuquerque (Correo Sandstone Bed), and possibly in the Sloan Canyon Formation of the Dry Cimarron valley. (D) Anaschisma-new phytosaur, cf. Typothorax-new sphenosuchian, occurs in the Redonda Formation near Tucumcari. The biochronologic ranges of significant vertebrate taxa within New Mexico follow: metoposaurs - Metoposaurus (A-B ), Anaschisma (B-D); phytosuars - Rutiodon (A), Belodon (B-C), new taxon (D); aetosaurs - Calyptosuchus (A), Desmatosuchus (A-B), Paratypothorax (B), Typothorax (B-D ); rauisuchians - Postosuchus (A-B), Chatterjeea (B-C); sphenosuchians - new taxon 1 (A), Hesperosuchus (B), new taxon 2 (D); dinosaurs - ornithischians (B), Coelophysis (C), other theropods (B-C); therapsids - Placerias (A), Pseudotriconodon (C). Biochron A may be Carnian in age, whereas biochrons B-D are probably early to middle ( ) Norian.

  13. Complications of Posterior Vertebral Resection for Spinal Deformity

    PubMed Central

    Kim, Sung-Soo; Cho, Beom-Cheol; Kim, Jin-Hyok; Park, Ji-Yong; Lee, Beom-Jung; Suk, Se-Il

    2012-01-01

    Study Design Retrospective study. Purpose To evaluate the incidence and risk factors of complications following posterior vertebral resection (PVR) for spinal deformity. Methods A review of 233 patients treated with PVR at one institution over a nine-year period (1997 to 2005) was performed. The average age was 33.5 years. Complications were assessed in terms of surgical techniques (posterior vertebral column resection [PVCR] and decancellation osteotomy) and etiologies of deformity. Results Local kyphosis was corrected from 51.4° to 2.7°, thoracic scoliosis 63.9° to 24.5° (62.6% correction), and thoracolumbar or lumbar scoliosis 50.1° to 17.1° (67.6%). The overall incidence of complications was 40.3%. There was no significant difference between PVCR and decancellation osteotomy in the incidence of complications. There were more complications in the older patients (>35 years) than the younger (p < 0.05). Hig her than 3,000 ml of blood loss and 200 minutes of operation time increased the incidence of complications, with significant difference (p < 0.05). More than 5 levels of fusion significantly increased the total number of complications and postoperative neurologic deficit (p < 0.05). Most of the postoperative paraplegia cases had preoperative neurologic deficit. Preoperative kyphosis, especially in tuberculous sequela, had hig her incidences of complications and postoperative neurologic deficit (p < 0.05). More than 40° of kyphosis correction had the tendency to increase complications and postoperative neurologic deficit without statistical significance (p > 0.05). There was 1 mortality case by heart failure. Revision surgery was performed in 15 patients for metal failure or progressing curve. Conclusions The overall incidence of complications of PVR was 40.3%. Older age, abundant blood loss, preoperative kyphosis, and long fusion were risk factors for complications. PMID:23275809

  14. Can initial clinical assessment exclude thoracolumbar vertebral injury?

    PubMed Central

    Gill, Dinendra Singh; Mitra, Biswadev; Reeves, Fairleigh; Cameron, Peter A; Fitzgerald, Mark; Liew, Susan; Varma, Dinesh

    2013-01-01

    Introduction The aim of this study was to test the hypothesis that all blunt trauma patients, presenting with a Glasgow coma scale (GCS) score of 15, without intoxication or neurological deficit, and no pain or tenderness on log-roll can have any thoracolumbar fracture excluded without imaging. Materials and Methods All patients diagnosed with a thoracolumbar fracture presenting to the emergency department of a major trauma centre and having an initial GCS score of 15 were included in the study. Variables collected included type of fracture, mechanism of injury, the presence of pain or tenderness on log-roll, ethanol levels and prehospital opioid analgesia. Results There were 536 patients with thoracolumbar fractures, of which 508 (94.8%) patients had either pain, tenderness or had received prehospital opioid analgesia. A small subgroup of 28 (5.2%) patients who received no prehospital opioid analgesia, did not complain of pain and had no tenderness to the thoracolumbar spine elicited on log-roll. This subgroup was significantly older (p=0.033) and a high proportion of patients (64.3%) had a concurrent fracture of the cervical spine. Within this subgroup, a clinically significant unstable thoracic fracture was present in three patients, with all three patients exhibiting symptoms and signs of neurological injury or having a concurrent cervical vertebral fracture. Conclusions In this population of blunt trauma patients with a GCS score of 15, not under the influence of alcohol or prehospital morphine administration, the absence of pain or tenderness on log-roll can exclude a clinically significant lumbar vertebral fracture, but does not exclude a thoracic fracture. PMID:22915226

  15. Vascular Plant and Vertebrate Inventory of Coronado National Memorial

    USGS Publications Warehouse

    Schmidt, Cecilia A., (Edited By); 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.

  16. 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.

  17. Molecular evolution of the vertebrate mechanosensory cell and ear

    PubMed Central

    Fritzsch, Bernd; Beisel, Kirk W.; Pauley, Sarah; Soukup, Garrett

    2014-01-01

    The molecular basis of mechanosensation, mechanosensory cell development and mechanosensory organ development is reviewed with an emphasis on its evolution. In contrast to eye evolution and development, which apparently modified a genetic program through intercalation of genes between the master control genes on the top (Pax6, Eya1, Six1) of the hierarchy and the structural genes (rhodopsin) at the bottom, the as yet molecularly unknown mechanosensory channel precludes such a firm conclusion for mechanosensors. However, recent years have seen the identification of several structural genes which are involved in mechanosensory tethering and several transcription factors controlling mechanosensory cell and organ development; these warrant the interpretation of available data in very much the same fashion as for eye evolution: molecular homology combined with potential morphological parallelism. This assertion of molecular homology is strongly supported by recent findings of a highly conserved set of microRNAs that appear to be associated with mechanosensory cell development across phyla. The conservation of transcription factors and their regulators fits very well to the known or presumed mechanosensory specializations which can be mostly grouped as variations of a common cellular theme. Given the widespread distribution of the molecular ability to form mechanosensory cells, it comes as no surprise that structurally different mechanosensory organs evolved in different phyla, presenting a variation of a common theme specified by a conserved set of transcription factors in their cellular development. Within vertebrates and arthropods, some mechanosensory organs evolved into auditory organs, greatly increasing sensitivity to sound through modifications of accessory structures to direct sound to the specific sensory epithelia. However, while great attention has been paid to the evolution of these accessory structures in vertebrate fossils, comparatively less attention has

  18. Non-participants differ from participants as regards risk factors for vertebral deformities: a source of misinterpretation in the European Vertebral Osteoporosis Study.

    PubMed

    Hasserius, Ralph; Karlsson, Magnus K; Nilsson, Bo E; Redlund-Johnell, Inga; Johnell, Olof

    2002-08-01

    Interpretation of data in epidemiological cohort studies may be confounded if differences exist between non-participants and participants. In the Malmö part of the European Vertebral Osteoporosis Study (EVOS), which was designed to evaluate the prevalence of vertebral deformity in 50-80-year-old persons, we compared 74 men and 95 women who had been invited, but declined to participate with age- and gender-matched participants as regards alcohol abuse, previous fractures and subsequent mortality, factors known to affect the prevalence of vertebral deformity. We found more men with alcohol abuse, more men with a previous fragility fracture and a tendency to more men with a previous clinical vertebral fracture among the non-participants than in the male participants. In contrast, there were fewer female non-participants than female participants with a previous clinical vertebral fracture. The mortality rate during the decade after the baseline examination was higher among both male and female non-participants. The "true" prevalence of vertebral deformity in the whole male population at risk in Malmö seems to be underestimated in the EVOS study. In women, it is more difficult to estimate the combined result of the confounding factors. Conclusions based on the EVOS participants may not be applicable to the whole population at risk. PMID:12358120

  19. Regions identity between the genome of vertebrates and non-retroviral families of insect viruses

    PubMed Central

    2011-01-01

    Background The scope of our understanding of the evolutionary history between viruses and animals is limited. The fact that the recent availability of many complete insect virus genomes and vertebrate genomes as well as the ability to screen these sequences makes it possible to gain a new perspective insight into the evolutionary interaction between insect viruses and vertebrates. This study is to determine the possibility of existence of sequence identity between the genomes of insect viruses and vertebrates, attempt to explain this phenomenon in term of genetic mobile element, and try to investigate the evolutionary relationship between these short regions of identity among these species. Results Some of studied insect viruses contain variable numbers of short regions of sequence identity to the genomes of vertebrate with nucleotide sequence length from 28 bp to 124 bp. They are found to locate in multiple sites of the vertebrate genomes. The ontology of animal genes with identical regions involves in several processes including chromatin remodeling, regulation of apoptosis, signaling pathway, nerve system development and some enzyme-like catalysis. Phylogenetic analysis reveals that at least some short regions of sequence identity in the genomes of vertebrate are derived the ancestral of insect viruses. Conclusion Short regions of sequence identity were found in the vertebrates and insect viruses. These sequences played an important role not only in the long-term evolution of vertebrates, but also in promotion of insect virus. This typical win-win strategy may come from natural selection. PMID:22073942

  20. Using Independent Research Projects to Foster Learning in the Comparative Vertebrate Anatomy Laboratory

    ERIC Educational Resources Information Center

    Ghedotti, Michael J.; Fielitz, Christopher; Leonard, Daniel J.

    2005-01-01

    This paper presents a teaching methodology involving an independent research project component for use in undergraduate Comparative Vertebrate Anatomy laboratory courses. The proposed project introduces cooperative, active learning in a research context to comparative vertebrate anatomy. This project involves pairs or groups of three students…