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Sample records for planaria

  1. Taxonomy Icon Data: Planaria [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Planaria Dugesia japonica Platyhelminthes Dugesia_japonica_L.png Dugesia_japonica_NL.png Dugesia_japon...ica_S.png Dugesia_japonica_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Dugesia+japon...ica&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Dugesia+japonica&t=NL http://biosciencedbc.j...p/taxonomy_icon/icon.cgi?i=Dugesia+japonica&t=S http://biosciencedbc.jp/taxonomy_...icon/icon.cgi?i=Dugesia+japonica&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=124 ...

  2. A Method for Dispensing Planaria (Dugesia dorotocephala) for Mosquito Control

    Science.gov (United States)

    1988-12-01

    other day. Planaria surviving Turbellaria ) was first shown by Lischetti (1919). after 14 days and those added to the population Studies have since...FILE COPY DECEMBER 198S OPERATIONAl. AND StCIENTIFI( NOTES A METHOD FOR DISPENSING PLANARIA (DI’E.S’IA DOROTOCEPHALA) FOR MOSQUITO CONTROL SW. N1...potential as number of experimental (12.64 ± 2.99) and con- a biological control agent of mosquitoes (Yu and trol (11.99 ± 2.47) planaria remaining after 14

  3. The phyletic status of the genus Planaria (Platyhelminthes, Turbellaria, Tricladida)

    NARCIS (Netherlands)

    Ball, Ian R.; Gourbault, Nicole

    1978-01-01

    The amphiatlantic distribution of the genus Planaria is incompatible with our current hypothesis of the historical biogeography of freshwater planarians. New anatomical studies suggest the possibility that the genus is not strictly monophyletic; new karyological data are strongly corroborative of th

  4. Effects of Water Quality on Survival and Reproduction of Four Species of Planaria (Turbellaria: Tricladida)

    Science.gov (United States)

    1994-01-01

    EB 24 ’ L Effects of water quality on survival and reproduction of four species of planaria ( Turbellaria : Tricladida)" V.R. RIVERAI and M.J. PERICH2...Introduction Historically, researchers have investigated planar- ians for their regeneration, physiology, memory and Planaria ( Turbellaria : Tricladida) are...determined to be the most adaptable and tolerant of the species evaluated. _ Key words: Planaria , water quality, survival, reproduction 0

  5. An Exploratory Evaluation of Tyrosine Hydroxylase Inhibition in Planaria as a Model for Parkinsonism

    Directory of Open Access Journals (Sweden)

    David Prokai

    2013-11-01

    Full Text Available Planaria are the simplest organisms with bilateral symmetry and a central nervous system (CNS with cephalization; therefore, they could be useful as model organisms to investigate mechanistic aspects of parkinsonism and to screen potential therapeutic agents. Taking advantage of the organism’s anti-tropism towards light, we measured a significantly reduced locomotor velocity in planaria after exposure to 3-iodo-L-tyrosine, an inhibitor of tyrosine hydroxylase that is an enzyme catalyzing the first and rate-limiting step in the biosynthesis of catecholamines. A simple semi-automatic assay using videotaped experiments and subsequent evaluation by tracking software was also implemented to increase throughput. The dopaminergic regulation of locomotor velocity was confirmed by bromocriptine, a drug whose mechanisms of action to treat Parkinson’s disease is believed to be through the stimulation of nerves that control movement.

  6. Schild (apparent pA2) analysis of a kappa-opioid antagonist in Planaria.

    Science.gov (United States)

    Raffa, Robert B; Baron, David A; Tallarida, Ronald J

    2006-07-01

    Previous investigators have provided radioimmunological and immunocytochemical evidence for an enkephalinergic (opioid) system in Planaria and described naloxone-sensitive qualitative behavioral responses to kappa-opioid receptor agonists. We report the application of Schild-analysis to the antagonism of a selective kappa agonist (U-50,488H) by a selective kappa antagonist (nor-BNI) in a quantitative in vivo endpoint. The results provide further evidence of a kappa-opioid-like receptor in planarians.

  7. Persistent conditioned place preference to cocaine and withdrawal hypo-locomotion to mephedrone in the flatworm planaria.

    Science.gov (United States)

    Hutchinson, Claire V; Prados, Jose; Davidson, Colin

    2015-04-23

    The purpose of the present study was to determine the effects of exposure to cocaine and mephedrone on conditioned place preference (CPP) and locomotion in the flatworm planaria. Planaria were treated with either cocaine or mephedrone at 1 or 10 μM. Planaria were exposed to 15 min of drug in their non-preferred place (either a rough- or smooth-floored petri dish) on alternate days, and were exposed to normal water in their preferred place on the following day. There were 5 days of conditioning to drug. Planaria were then tested for CPP on day 2, 6 and 13 after withdrawal. We found that animals exhibited CPP to cocaine at both 1 and 10 μM, but not to mephedrone. When examining locomotor activity we found that neither cocaine nor mephedrone treatment showed any evidence of evoking increased motility or locomotor sensitisation. Hypo-motility was seen on the first day of conditioning at concentrations of 10 μM for both cocaine and mephedrone, but had disappeared by the last day of conditioning. Examining chronic withdrawal, only 10 μM mephedrone had a significant effect on motility, decreasing locomotion on day 2 of withdrawal. Taken together we have shown that cocaine evoked CPP in planaria. We have also shown withdrawal depressing effects of mephedrone on motility.

  8. Cysteine and Aspartyl Proteases Contribute to Protein Digestion in the Gut of Freshwater Planaria.

    Directory of Open Access Journals (Sweden)

    Louise S Goupil

    2016-08-01

    Full Text Available Proteases perform numerous vital functions in flatworms, many of which are likely to be conserved throughout the phylum Platyhelminthes. Within this phylum are several parasitic worms that are often poorly characterized due to their complex life-cycles and lack of responsiveness to genetic manipulation. The flatworm Schmidtea mediterranea, or planaria, is an ideal model organism to study the complex role of protein digestion due to its simple life cycle and amenability to techniques like RNA interference (RNAi. In this study, we were interested in deconvoluting the digestive protease system that exists in the planarian gut. To do this, we developed an alcohol-induced regurgitation technique to enrich for the gut enzymes in S. mediterranea. Using a panel of fluorescent substrates, we show that this treatment produces a sharp increase in proteolytic activity. These enzymes have broad yet diverse substrate specificity profiles. Proteomic analysis of the gut contents revealed the presence of cysteine and metallo-proteases. However, treatment with class-specific inhibitors showed that aspartyl and cysteine proteases are responsible for the majority of protein digestion. Specific RNAi knockdown of the cathepsin B-like cysteine protease (SmedCB reduced protein degradation in vivo. Immunohistochemistry and whole-mount in situ hybridization (WISH confirmed that the full-length and active forms of SmedCB are found in secretory cells surrounding the planaria intestinal lumen. Finally, we show that the knockdown of SmedCB reduces the speed of tissue regeneration. Defining the roles of proteases in planaria can provide insight to functions of conserved proteases in parasitic flatworms, potentially uncovering drug targets in parasites.

  9. Vertically- and horizontally-transmitted memories – the fading boundaries between regeneration and inheritance in planaria

    Science.gov (United States)

    Neuhof, Moran; Levin, Michael; Rechavi, Oded

    2016-01-01

    ABSTRACT The Weismann barrier postulates that genetic information passes only from the germline to the soma and not in reverse, thus providing an obstacle to the inheritance of acquired traits. Certain organisms such as planaria – flatworms that can reproduce through asymmetric fission – avoid the limitations of this barrier, thus blurring the distinction between the processes of inheritance and development. In this paper, we re-evaluate canonical ideas about the interaction between developmental, genetic and evolutionary processes through the lens of planaria. Biased distribution of epigenetic effects in asymmetrically produced parts of a regenerating organism could increase variation and therefore affect the species' evolution. The maintenance and fixing of somatic experiences, encoded via stable biochemical or physiological states, may contribute to evolutionary processes in the absence of classically defined generations. We discuss different mechanisms that could induce asymmetry between the two organisms that eventually develop from the regenerating parts, including one particularly fascinating source – the potential capacity of the brain to produce long-lasting epigenetic changes. PMID:27565761

  10. Subadditive withdrawal from cocaine/kappa-opioid agonist combinations in Planaria.

    Science.gov (United States)

    Raffa, Robert B; Stagliano, Gregory W; Tallarida, Ronald J

    2006-10-09

    We have previously developed and extensively characterized a convenient and sensitive metric for the quantification of withdrawal responses using Planaria. Planaria are particularly valuable for these studies because of their permeable exteriors and their relevant neurotransmitter systems (e.g., dopaminergic, opioid, and serotonergic). In the present study, we used this metric and mathematically rigorous joint-action analysis to investigate poly-drug withdrawal from fixed-ratio cocaine/kappa-opioid agonist combinations. The D50 (concentration producing half-maximal effect) for cocaine and U-50,488H was 10.3 and 1.02 microg, respectively. The D50 for 19:1 or 1:19 combinations did not differ significantly (p>0.05) from expected additive values (11.6+/-3.0 vs. 9.9+/-1.4 and 1.1+/-0.2 vs. 1.5+/-0.1, respectively), but the 3:1, 1:1, and 1:3 ratios did (34.5+/-6.9 vs. 7.7+/-1.1; 55.1+/-10.0 vs. 5.7+/-0.7; and 40.8+/-8.9 vs. 3.3+/-0.4, respectively), indicating subadditive interaction at these ratios. The finding of subadditivity in this model suggests that abstinence-induced withdrawal from the combination is less intense than that predicted from the individual drug potencies. The concept that certain combinations of drugs leads to attenuated withdrawal might generalize to humans.

  11. Vertically- and horizontally-transmitted memories – the fading boundaries between regeneration and inheritance in planaria

    Directory of Open Access Journals (Sweden)

    Moran Neuhof

    2016-09-01

    Full Text Available The Weismann barrier postulates that genetic information passes only from the germline to the soma and not in reverse, thus providing an obstacle to the inheritance of acquired traits. Certain organisms such as planaria – flatworms that can reproduce through asymmetric fission – avoid the limitations of this barrier, thus blurring the distinction between the processes of inheritance and development. In this paper, we re-evaluate canonical ideas about the interaction between developmental, genetic and evolutionary processes through the lens of planaria. Biased distribution of epigenetic effects in asymmetrically produced parts of a regenerating organism could increase variation and therefore affect the species' evolution. The maintenance and fixing of somatic experiences, encoded via stable biochemical or physiological states, may contribute to evolutionary processes in the absence of classically defined generations. We discuss different mechanisms that could induce asymmetry between the two organisms that eventually develop from the regenerating parts, including one particularly fascinating source – the potential capacity of the brain to produce long-lasting epigenetic changes.

  12. Opioid receptor types involved in the development of nicotine physical dependence in an invertebrate (Planaria) model.

    Science.gov (United States)

    Raffa, Robert B; Baron, Steve; Bhandal, Jaspreet S; Brown, Tevin; Song, Kevin; Tallarida, Christopher S; Rawls, Scott M

    2013-11-01

    Recent data suggest that opioid receptors are involved in the development of nicotine physical dependence in mammals. Evidence in support of a similar involvement in an invertebrate (Planaria) is presented using the selective opioid receptor antagonist naloxone, and the more receptor subtype-selective antagonists CTAP (D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2) (μ, MOR), naltrindole (δ, DOR), and nor-BNI (norbinaltorphimine) (κ, KOR). Induction of physical dependence was achieved by 60-min pre-exposure of planarians to nicotine and was quantified by abstinence-induced withdrawal (reduction in spontaneous locomotor activity). Known MOR and DOR subtype-selective opioid receptor antagonists attenuated the withdrawal, as did the non-selective antagonist naloxone, but a KOR subtype-selective antagonist did not. An involvement of MOR and DOR, but not KOR, in the development of nicotine physical dependence or in abstinence-induced withdrawal was thus demonstrated in a sensitive and facile invertebrate model.

  13. Fine-scale differences in diel activity among nocturnal freshwater planarias (Platyhelminthes: Tricladida

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    Cicolani Bruno

    2011-04-01

    Full Text Available Abstract Background Although most freshwater planarias are well known photonegative organisms, their diel rhythms have never been quantified. Differences in daily activity rhythms may be particularly important for temperate-climate, freshwater planarias, which tend to overlap considerably in spatial distribution and trophic requirements. Methods Activity of stress-free, individually tested young adults of three common planarian species was recorded at 3-h intervals in a 10-d experiment under natural sunlight and photoperiod during autumnal equinox (D:L ~12:12. Individual activity status was averaged over the 10-d experiment, each tested individual thus serving as a true replicate. Twelve individuals per species were tested. Food was provided every 36 h, resulting in alternating day- and nighttime feeding events. Activity during the first post-feeding h was recorded and analyzed separately. Statistical procedures included ANOVAs, correlations, and second-order analyses of angles. Results Dugesia (= Girardia tigrina Girard 1850 exhibited clear nocturnal behavior, Dugesia (= Schmidtea polychroa Schmidt 1861 was predominantly but not exclusively nocturnal, and Polycelis tenuis Ijima 1884 was relatively more active from midnight through noon. Species-specific activity peaks were statistically similar, with peaks at dawn for P. tenuis and just before midnight for the two dugesiids; however, D. tigrina was comparatively more active in the early night hours, while D. polychroa was more active than D. tigrina during daytime. D. tigrina also responded less readily to daytime food addition. P. tenuis remained poorly active and unresponsive throughout the experiment. Individual variability in diel behavior was highest for D. polychroa and lowest for D. tigrina. P. tenuis's general low degree of activity and late activity peak in the experiment may be related to a strong reliance on external stimuli. Conclusions The tested species are mainly nocturnal

  14. The blue land planarian Caenoplana coerulea, an invader in Argentina La planaria terrestre azul Caenoplana coerulea, un invasor en Argentina

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    Lisandro Héctor Luis-Negrete

    2011-03-01

    Full Text Available The blue land planarian Caenoplana coerulea is reported from Argentina (Buenos Aires province. We found C. coerulea in the east central region of Argentina in anthropic environments. The specimens that we found have the characteristic of the species found in others regions; that is, a bluish dorsal surface with a yellow mid-dorsal stripe and eyes forming a single row around the anterior tip, clustered laterally. This is the first record of this species from the Neotropical Region, and together with Bipalium kewense are the only 2 species of exotic terrestrial planarians so far recorded in Argentina.La planaria terrestre azul Caenoplana coerulea se registra para el centro este de Argentina (provincia de Buenos Aires, en ambientes antropizados. Los ejemplares encontrados presentan las características de la especie registrada en otras regiones, con una superficie dorsal azulada y una hilera medio dorsal amarilla, y ojos formando una hilera alrededor del extremo anterior, agrupados lateralmente. Es la primera vez que se cita dicha especie en la Región Neotropical, y junto a Bipalium kewense son las únicas planarias terrestres exóticas registradas en Argentina.

  15. Caracterización funcional de la vía Wnt/Bcatenina en el restablecimiento y mantenimiento del eje anteroposterior durante la regeneración y homeostasis de la planaria Schmidtea mediterranea

    OpenAIRE

    Iglesias García, Marta

    2016-01-01

    La gran mayoría de planarias son capaces de regenerar, y cuando lo hacen, invariablemente mantienen la polaridad de regeneración; es decir, siempre regeneran una cabeza en las heridas anteriores y una cola en las posteriores al ser amputadas transversalmente. Entender los mecanismos que subyacen dicho fenómeno ha sido objeto de investigación desde finales del siglo XIX. Asimismo, muchos investigadores se han interesado en comprender como una planaria mantiene las proporciones corporales dura...

  16. Stimulus polarity and conditioning in planaria.

    Science.gov (United States)

    BARNES, C D; KATZUNG, B G

    1963-08-23

    Orientation in the monopolar pulse field used as the unconditioned stimulus was found to influence formation of a conditioned response to light in planarians. Planarians trained while oriented with the head toward the cathode reached maximal response rates rapidly, while those trained while oriented toward the anode showed no evidence of conditioned response formation.

  17. A Simple Method for Isolation of Neoblasts from Planaria

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    Hamed Chitsazan

    2009-01-01

    Full Text Available Objective: Freshwater planarians were used as models for studying metazoan regenerationand stem cell biology. Here a simple, fast and high throughput method for extracting theirstem cells (neoblasts is represented.Materials and Methods: Specimens of the Dugesia sp with an average length of 18 mmwere homogenized by a glass Dounce tissue grinder which contained about 1 ml of planariansaline solution. The extracted suspension was serially filtered by 60, 41, 30, 20 and 11 μmnylon meshes. In order to obtain purified neoblasts in the final suspension; this suspensionhas been compared with a cell suspension from 30 Gy irradiated worms. Hoechst 33342was used to determine cells from non-cellular particles; methylene blue and propidium iodidewere used to detect the number of dead cells in each extraction.Results: About 2.6-3 million cells were extracted from 10-12 worms. Flow cytometry analysisshowed about 83% of the extracted particles were cells. In suspensions from irradiatedanimals, about 50% of the cells were absent, the final suspension contained about 62-66%neoblasts and about 17% non-cellular particles. When these extracts were treated with distilledwater to destroy the cells, only rabdites and chitinous spines of the parenchyma wereobserved in the extract.Conclusion: Results show that the purity of neoblasts in the final suspension is about 66%.Non-cellular particles have a carbohydrate nature and, therefore, this extraction method iscompletely compatible with molecular (e.g. proteomics and transcriptomics and cellularmethods (e.g. neoblast culture.

  18. Presence of galactosylated core fucose on N-glycans in the planaria Dugesia japonica.

    Science.gov (United States)

    Paschinger, Katharina; Razzazi-Fazeli, Ebrahim; Furukawa, Kiyoshi; Wilson, Iain B H

    2011-06-01

    Planarial species are of especial interest to biologists due to the phenomenon of pluripotency and, in comparison to other developmental processes, it can be hypothesised that glycan-lectin interactions may play a role. In order to examine the N-glycans of one of these organisms, Dugesia japonica, peptide:N-glycosidase A was employed and the released glycans were subject to pyridylamination, HPLC and mass spectrometric analysis. A range of oligomannosidic glycans was observed with a trimethylated Man(5) GlcNAc(2) structure being the dominant species. Three glycans were also observed to contain deoxyhexose; in particular, a glycan with the composition Hex(4) HexNAc(2) Fuc(1) Me(2) was revealed by exoglycosidase digestion, in combination with MS/MS, to contain a galactosylated core α1,6-fucose residue, whereas this core modification was found to be capped with a methylhexose residue in the case of a Hex(5) HexNAc(2) Fuc(1) Me(3) structure. This is the first report of these types of structures in a platyhelminth and indicates that the 'GalFuc' modification of N-glycans is not just restricted to molluscs and nematodes.

  19. An Outer Arm Dynein Conformational Switch Is Required for Metachronal Synchrony of Motile Cilia in Planaria

    Science.gov (United States)

    Rompolas, Panteleimon; Patel-King, Ramila S.

    2010-01-01

    Motile cilia mediate the flow of mucus and other fluids across the surface of specialized epithelia in metazoans. Efficient clearance of peri-ciliary fluids depends on the precise coordination of ciliary beating to produce metachronal waves. The role of individual dynein motors and the mechanical feedback mechanisms required for this process are not well understood. Here we used the ciliated epithelium of the planarian Schmidtea mediterranea to dissect the role of outer arm dynein motors in the metachronal synchrony of motile cilia. We demonstrate that animals that completely lack outer dynein arms display a significant decline in beat frequency and an inability of cilia to coordinate their oscillations and form metachronal waves. Furthermore, lack of a key mechanosensitive regulatory component (LC1) yields a similar phenotype even though outer arms still assemble in the axoneme. The lack of metachrony was not due simply to a decrease in ciliary beat frequency, as reducing this parameter by altering medium viscosity did not affect ciliary coordination. In addition, we did not observe a significant temporal variability in the beat cycle of impaired cilia. We propose that this conformational switch provides a mechanical feedback system within outer arm dynein that is necessary to entrain metachronal synchrony. PMID:20844081

  20. Selective amputation of the pharynx identifies a FoxA-dependent regeneration program in planaria

    Science.gov (United States)

    Adler, Carolyn E; Seidel, Chris W; McKinney, Sean A; Sánchez Alvarado, Alejandro

    2014-01-01

    Planarian flatworms regenerate every organ after amputation. Adult pluripotent stem cells drive this ability, but how injury activates and directs stem cells into the appropriate lineages is unclear. Here we describe a single-organ regeneration assay in which ejection of the planarian pharynx is selectively induced by brief exposure of animals to sodium azide. To identify genes required for pharynx regeneration, we performed an RNAi screen of 356 genes upregulated after amputation, using successful feeding as a proxy for regeneration. We found that knockdown of 20 genes caused a wide range of regeneration phenotypes and that RNAi of the forkhead transcription factor FoxA, which is expressed in a subpopulation of stem cells, specifically inhibited regrowth of the pharynx. Selective amputation of the pharynx therefore permits the identification of genes required for organ-specific regeneration and suggests an ancient function for FoxA-dependent transcriptional programs in driving regeneration. DOI: http://dx.doi.org/10.7554/eLife.02238.001 PMID:24737865

  1. Rinvenimento di una Planaria ascrivibile a Dugesia etrusca monoadenodactyla Lepori (Turbellaria, Tricladida) nell'Isola di Molara (Sardegna)

    OpenAIRE

    Pala, Maria; Casu, Salvatore; Vacca, Rosa Alba

    1980-01-01

    The Molara planarian belonging to the group gonocephala should not be ascribed to the Dugesia benazzii of Sardinia and Corsica, but to Dugesia etrusca monoadenodactyla found in the province of Grosseto and described by Lepori in 1947. It was established that the Molara planarian belongs to the above-mentioned race by histological examination of the copulatory system as well as on the basis of its chromosome equipment which is of the 2n=16; n=8 type.

  2. Screening of Native Rotifers, Hydra, Planaria for Deriving Aquatic Life Criteria%水生生物水质基准研究中轮虫、水螅、涡虫类受试生物的筛选

    Institute of Scientific and Technical Information of China (English)

    郑欣; 闫振广; 刘征涛; 刘婷婷; 王晓南; 武江越; 王伟莉

    2015-01-01

    轮虫、水螅、涡虫是水生生态系统的重要生物类群.因其对水体污染较敏感,所以对水生生物基准研究有重要意义.依据我国生物区系资料及毒性数据丰度,筛选出8种代表性本土轮虫、水螅、涡虫类生物.参照美国水生生物基准技术指南,搜集、筛选了这8种代表性生物的急性毒性数据,通过数据分析,筛选出对各物种毒性最大的污染物,主要包括重金属、农药、有机锡化物、表面活性剂、吡啶胺类杀菌剂.分析污染物的物种敏感度分布,依据累积概率对代表性生物的物种敏感性进行分类,结果为:萼花臂尾轮虫(Brachionus calyciflorus)、绿水螅(Hydrav iridissima)、普通水螅(Hydra vulgaris)对重金属铜的累积概率为6.5%、85%和10.4%,普通水螅(Hydra vulgaris)对重金属汞的累积概率为6.3%;龟甲轮虫(Keratella cochlearis)和四齿腔轮虫(Lecane quadridentata)对五氯酚钠的累积概率为5.1%和7.6%;褐水螅(Hydrao ligactis)和绿水螅(Hydra viridissima)对三丁基氧化锡的累积概率为6.9%和13.8%,萼花臂尾轮虫(Brachionus calyciflorus)对氟啶胺的累积概率为6.7%,日本三角涡虫(Dugesia japonica)对四氯化碳、十二烷基苯磺酸钠的累积概率分别为6.7%和7.1%.上述结果表明:萼花臂尾轮虫、绿水螅对重金属铜敏感;普通水螅对重金属铜和汞敏感;龟甲轮虫和四齿腔轮虫对农药敏感;褐水螅和绿水螅对有机锡化物敏感;萼花臂尾轮虫对吡啶胺类杀菌剂敏感;日本三角涡虫对四氯化碳、表面活性剂敏感.这7种代表性生物可作为相关污染物的水生生物基准受试物种.

  3. Dugesia hepta, nuova specie di Planaria di acqua dolce di Sardegna appartenente alla superspecie Dugesia gonocephala (Dugès) (Turbellaria, Tricladida)

    OpenAIRE

    Pala, Maria; Casu, Salvatore; Vacca, Rosa Alba

    1981-01-01

    A planarian belonging to the group Dugesia gonocephala s.l. was found in thirteen sites in Sardinia (eleven in the catchment area of the Rio Mannu of Porto Torres and two in that of the Coghinas). It is morphologically related to Dugesia benazzii Lepori of Sardinia and Corsica but presents a different caryotype: 2n=14; n=7 chromosomes instead of 2n=16; n=8 chromosomes. The latter is considered to be the most common in the superspecies Dugesia gonocephala of central European and Mediterr...

  4. Image files of planarians analyzed by in situ hybridication and immunohistochemical staining - Plabrain DB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available ans or planarian head regions in the regeneration process. Images are displayed in A list of image files of ...file File name: planaria_image.zip File URL: ftp://ftp.biosciencedbc.jp/archive/p...labrain-db/LATEST/planaria_image.zip File size: 2.74MB Simple search URL - Data acquisition method Whole-mou

  5. Clarks Hill Lake Water Quality Study.

    Science.gov (United States)

    1982-06-01

    MACROINVERTEBRATE TAXONOMIC LIST CLARKS HILL LAKE 1981 Phylum Platyhelminthes Order Diptera Class Turbellaria Ablabesmyia parajanta unidentified Planariidae A...HILL LAKE 1981 Phylum Platyhelminthes Order Diptera (continued) Planaria sp.,’ Bezzia sp. 2 unidentified Planariidae Chaoborus punctipennis unidentified

  6. Galantamine reverses scopolamine-induced behavioral alterations in Dugesia tigrina.

    Science.gov (United States)

    Ramakrishnan, Latha; Amatya, Christina; DeSaer, Cassie J; Dalhoff, Zachary; Eggerichs, Michael R

    2014-09-01

    In planaria (Dugesia tigrina), scopolamine, a nonselective muscarinic receptor antagonist, induced distinct behaviors of attenuated motility and C-like hyperactivity. Planarian locomotor velocity (pLMV) displayed a dose-dependent negative correlation with scopolamine concentrations from 0.001 to 1.0 mM, and a further increase in scopolamine concentration to 2.25 mM did not further decrease pLMV. Planarian hyperactivity counts was dose-dependently increased following pretreatment with scopolamine concentrations from 0.001 to 0.5 mM and then decreased for scopolamine concentrations ≥ 1 mM. Planarian learning and memory investigated using classical Pavlovian conditioning experiments demonstrated that scopolamine (1 mM) negatively influenced associative learning indicated by a significant decrease in % positive behaviors from 86 % (control) to 14 % (1 mM scopolamine) and similarly altered memory retention, which is indicated by a decrease in % positive behaviors from 69 % (control) to 27 % (1 mM scopolamine). Galantamine demonstrated a complex behavior in planarian motility experiments since co-application of low concentrations of galantamine (0.001 and 0.01 mM) protected planaria against 1 mM scopolamine-induced motility impairments; however, pLMV was significantly decreased when planaria were tested in the presence of 0.1 mM galantamine alone. Effects of co-treatment of scopolamine and galantamine on memory retention in planaria via classical Pavlovian conditioning experiments showed that galantamine (0.01 mM) partially reversed scopolamine (1 mM)-induced memory deficits in planaria as the % positive behaviors increased from 27 to 63 %. The results demonstrate, for the first time in planaria, scopolamine's effects in causing learning and memory impairments and galantamine's ability in reversing scopolamine-induced memory impairments.

  7. A list of image files of planarians analyzed by in situ hybridication and immunohistochemical staining - Plabrain DB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available aining Data detail Data name A list of image files of planarians analyzed by in situ hybridication and immun...ohistochemical staining Description of data contents This list includes file names of image... immunohistochemical staining in intact planarians or planarian head regions in the regeneration process. A set of the image... In situ hybridication and immunohistochemical staining . Data file File name: planaria_image_list.zip File ...URL: ftp://ftp.biosciencedbc.jp/archive/plabrain-db/LATEST/planaria_image_list.zip File size: 1KB Simple sea

  8. The Journal of the Imagination in Language Learning and Teaching, 2001.

    Science.gov (United States)

    Coreil, Clyde, Ed.

    2001-01-01

    This collection of papers includes the following: "On the Educational Uses of Fantasy" (Geoffrey Madoc-Jones and Kieran Egan); "The Dangers of Empathy with Students" (Mario Rinvolucri); "The Magic of Folktales for Teaching English and Culture" (Planaria Price); "The Inner Voice: A Critical Factor in L2 Learning" (Brian Tomlinson); "Dance: An…

  9. Spiro Fused Diterpene-Indole Alkaloids from a Creek-Bottom-Derived Aspergillus terreus

    Science.gov (United States)

    Cai, Shengxin; Du, Lin; Gerea, Alexandra L.; King, Jarrod B.; You, Jianlan

    2013-01-01

    Four metabolites, teraspiridoles A–D (2–5), formed from the merger of diterpene and modified indole scaffold were obtained from an Aspergillus terreus isolate. The structures and absolute configurations of these natural products were established using NMR, mass spectrometry, Marfey’s method, VCD, and ECD data. Teraspiridole B (3) exhibited weak inhibition of planaria regeneration/survival. PMID:23924243

  10. Acute toxic responses of the freshwater planarian, Dugesia dorotocephala, to methylmercury

    Energy Technology Data Exchange (ETDEWEB)

    Best, J.B.; Morita, M.; Ragin, J.; Best, J. Jr.

    1981-07-01

    Toxic responses of planaria to various aquatic habitat concentrations of methylmercury chloride (MMC) were investigated. One hundred percent lethality occurred within 5 h in 2 ppM MMC, 24 h in 1 ppM MMC, and 5 days in 0.5 ppM MMC. No deaths occurred in 0.2 ppM MMC over a 10 day period, however, non-lethal toxic responses were observed. Varying degrees of head resorption, progressing caudally from the snout were observed. With continuing exposure, partial head regeneration and recovery toward more normal appearance occurred by 10 days. Teratogenic effects were observed in surgical decapitation experiments. Head regeneration was retarded in 0.1 and 0.2 ppM MMC. Malformations, visible lesions, or gross behavioral abnormalities were produced by 2 week exposure of planaria to concentrations of 20 ppB MMC or lower. (RJC)

  11. Estimation of the toxicity of silver nanoparticles by using planarian flatworms.

    Science.gov (United States)

    Kustov, Leonid; Tiras, Kharlampii; Al-Abed, Souhail; Golovina, Natalia; Ananyan, Mikhail

    2014-03-01

    The regeneration of planarian flatworms - specifically, changes to the area of the regeneration bud (blastema) after surgical dissection - was proposed for use as a robust tool for estimating the toxicity of silver nanoparticles. The use of Planaria species, due to their unique regenerative capacity, could result in a reduction in the use of more-traditional laboratory animals for toxicity testing. With our novel approach, silver nanoparticles were found to be moderately toxic to the planarian, Girardia tigrina.

  12. Planarians as a model of aging to study the interaction between stem cells and senescent cells in vivo

    Directory of Open Access Journals (Sweden)

    Patrick M. Perrigue

    2015-12-01

    Full Text Available The depletion of stem cell pools and the accumulation of senescent cells in animal tissues are linked to aging. Planarians are invertebrate flatworms and are unusual in that their stem cells, called neoblasts, are constantly replacing old and dying cells. By eliminating neoblasts in worms via irradiation, the biological principles of aging are exposed in the absence of wound healing and regeneration, making planaria a powerful tool for aging research.

  13. The Study of Regenerative Growth and Transdetermination in Drosophila melanogaster

    OpenAIRE

    2013-01-01

    Why some tissues can regenerate, while other cannot is a fundamental question for regenerative medicine. The ability to regenerate at least some tissues is widespread across diverse animals. Some, such as Hydra and planaria can regenerate the majority of their body, while urodele amphibians such as salamanders can regenerate the spinal cord in their tails and also a complete limb. Humans can regenerate tissues such as the liver, muscle and skin. There are diverse mechanisms of regenerations, ...

  14. [The molecular genetic typification of planarians in the genus Bdellocephala (Dendrocoelidae, Tricladida, Turbellaria) from Lake Baikal with an assessment of their species diversity].

    Science.gov (United States)

    Kuznedelov, K D; Novikova, O A; Naumova, T V

    2000-01-01

    Baikal planaria from genus Bdellocephala were typified using rDNA locus coding 5'--end domain of 18S ribosome RNA. Five colour forms of 24 possible variants that differ in diapason 0-1.3% of genotype were determined by comparative analysis of nucleotide sequences. The authors use back colour--one of the most variable and typical character in the given group--to collect material for investigation. It allows to minimize the size of investigation sample and at the same time to cover maximum variability of Bdellocephala. One of the positive result of molecular typification of colour forms was a discovery of unique individuals that belong to new species. Karyological analysis of colour forms shows variations in chromosome numbers that divide planaria into 3 groups (2n = 20, 24, 26). Comparative analysis of morphological and ecological characters and karyotypes of some forms united by the same genotype allows to distinguish them as separate species. Criteria of modern phenetic system of Baikal planaria are discussed.

  15. Effects of Withania somnifera and Ginkgo biloba on Neural Regeneration using Planarian Model

    Science.gov (United States)

    Singhal, M.; Brinker, R.

    2016-12-01

    Elderly populations and associated age-related diseases, including damaged peripheral and central neural systems, are increasing. Both systems are vital, and methods to sustain function are sought. The purpose of this experiment was to determine whether Withania somnifera (WS) and Ginkgo biloba (GB) extracts are conducive to planarian regeneration. After acclimation, brown planaria were cut across lateral nerve cord. Experimental groups were treated with 100μg WS or GB extract. Planarian length was measured and piece tested for negative phototaxis. In phototactic test, planaria were allowed 30 seconds to cross petri dish and stay under dark side. A positive response signified photoreceptor presence, indicating regeneration. Both GB and WS groups expressed more favorable cumulative regeneration rates than control group (97.31%, 71.44%, and 40.60% respectively). The null hypothesis (identical regeneration rates) was rejected (p-value ≈ 0.0375). Because phototactic data wasn't taken on days 4 and 5, there was no significant difference in average day of first phototactic response. Most WS and GB planaria first responded on day 6, suggesting that, had data been taken on days 4 and 5, both plant-treated groups would have exhibited even sooner responses than control. Future studies include quantifying regeneration via planarian locomotive velocity (pLMV) and other stereotypical responses.

  16. Image files of PCR data plotted on the FACS profiles - Plabrain DB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Plabrain DB Image files of PCR data plotted on the FACS profiles Data detail Data name Image... files of PCR data plotted on the FACS profiles DOI 10.18908/lsdba.nbdc01108-002 Description of data content...s FACS-based single-cell PCR data was plotted on the FACS profile, in which cells are sorted by DNA content ...(Hoechst33342) and cell size (CalceinAM). Blue dots indicate the +cells. Individual FACS profile...earch . Data file File name: planaria_facs_profile.zip File URL: http://togodb.biosciencedbc.jp/togodb/view/

  17. Zebrafish Ciliopathy Screen Plus Human Mutational Analysis Identifies C21orf59 and CCDC65 Defects as Causing Primary Ciliary Dyskinesia

    Science.gov (United States)

    Austin-Tse, Christina; Halbritter, Jan; Zariwala, Maimoona A.; Gilberti, Renée M.; Gee, Heon Yung; Hellman, Nathan; Pathak, Narendra; Liu, Yan; Panizzi, Jennifer R.; Patel-King, Ramila S.; Tritschler, Douglas; Bower, Raqual; O’Toole, Eileen; Porath, Jonathan D.; Hurd, Toby W.; Chaki, Moumita; Diaz, Katrina A.; Kohl, Stefan; Lovric, Svjetlana; Hwang, Daw-Yang; Braun, Daniela A.; Schueler, Markus; Airik, Rannar; Otto, Edgar A.; Leigh, Margaret W.; Noone, Peadar G.; Carson, Johnny L.; Davis, Stephanie D.; Pittman, Jessica E.; Ferkol, Thomas W.; Atkinson, Jeffry J.; Olivier, Kenneth N.; Sagel, Scott D.; Dell, Sharon D.; Rosenfeld, Margaret; Milla, Carlos E.; Loges, Niki T.; Omran, Heymut; Porter, Mary E.; King, Stephen M.; Knowles, Michael R.; Drummond, Iain A.; Hildebrandt, Friedhelm

    2013-01-01

    Primary ciliary dyskinesia (PCD) is caused when defects of motile cilia lead to chronic airway infections, male infertility, and situs abnormalities. Multiple causative PCD mutations account for only 65% of cases, suggesting that many genes essential for cilia function remain to be discovered. By using zebrafish morpholino knockdown of PCD candidate genes as an in vivo screening platform, we identified c21orf59, ccdc65, and c15orf26 as critical for cilia motility. c21orf59 and c15orf26 knockdown in zebrafish and planaria blocked outer dynein arm assembly, and ccdc65 knockdown altered cilia beat pattern. Biochemical analysis in Chlamydomonas revealed that the C21orf59 ortholog FBB18 is a flagellar matrix protein that accumulates specifically when cilia motility is impaired. The Chlamydomonas ida6 mutant identifies CCDC65/FAP250 as an essential component of the nexin-dynein regulatory complex. Analysis of 295 individuals with PCD identified recessive truncating mutations of C21orf59 in four families and CCDC65 in two families. Similar to findings in zebrafish and planaria, mutations in C21orf59 caused loss of both outer and inner dynein arm components. Our results characterize two genes associated with PCD-causing mutations and elucidate two distinct mechanisms critical for motile cilia function: dynein arm assembly for C21orf59 and assembly of the nexin-dynein regulatory complex for CCDC65. PMID:24094744

  18. Limnologic-geologic excursion in the territory of the lower Erft River

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, G.; Thome, K.N.

    1976-01-01

    The geography and hydrology of the area of the excursion are described. There is much damage due to brown coal strip mining operations. Ground water was drained through a canal leading to the Erft River. The water in nearby springs is rich in Fe which repels plant life. The canal contains only a few blue algae (Oscillatoria splendida) and filamentous green algae (Ulothrix tenerrima) which tolerate high Fe concentrations. The Erft shore plant population includes Sparganium erectum, Potamogeton natans, P. pectinatus and Ranunculus fluitans. On flowering plants and stones, diatoms, various green algae (Cladophora glomerata, Stigeoclonium tenue, Oedogonium capillare) and the tropical red alga Compsopogon hookeri were found. The macrozoobenthos is composed mainly of snails (Bithynia tenaculata, Lumnaea ovata, Physa fontinalis, P. acuta and worms of North American origin (Dugesia tifrina, Dendrocoelum lacteum and Planaria lugubris). The Isopoda included Asellus coxalis and A. aquaticus. Leeches (Herpobdella octoculata) and insect larvae (Chironomids, Limnephilids) were also found.

  19. Modeling planarian regeneration: a primer for reverse-engineering the worm.

    Science.gov (United States)

    Lobo, Daniel; Beane, Wendy S; Levin, Michael

    2012-01-01

    A mechanistic understanding of robust self-assembly and repair capabilities of complex systems would have enormous implications for basic evolutionary developmental biology as well as for transformative applications in regenerative biomedicine and the engineering of highly fault-tolerant cybernetic systems. Molecular biologists are working to identify the pathways underlying the remarkable regenerative abilities of model species that perfectly regenerate limbs, brains, and other complex body parts. However, a profound disconnect remains between the deluge of high-resolution genetic and protein data on pathways required for regeneration, and the desired spatial, algorithmic models that show how self-monitoring and growth control arise from the synthesis of cellular activities. This barrier to progress in the understanding of morphogenetic controls may be breached by powerful techniques from the computational sciences-using non-traditional modeling approaches to reverse-engineer systems such as planaria: flatworms with a complex bodyplan and nervous system that are able to regenerate any body part after traumatic injury. Currently, the involvement of experts from outside of molecular genetics is hampered by the specialist literature of molecular developmental biology: impactful collaborations across such different fields require that review literature be available that presents the key functional capabilities of important biological model systems while abstracting away from the often irrelevant and confusing details of specific genes and proteins. To facilitate modeling efforts by computer scientists, physicists, engineers, and mathematicians, we present a different kind of review of planarian regeneration. Focusing on the main patterning properties of this system, we review what is known about the signal exchanges that occur during regenerative repair in planaria and the cellular mechanisms that are thought to underlie them. By establishing an engineering-like style

  20. The TALE class homeobox gene Smed-prep defines the anterior compartment for head regeneration.

    Directory of Open Access Journals (Sweden)

    Daniel A Felix

    2010-04-01

    Full Text Available Planaria continue to blossom as a model system for understanding all aspects of regeneration. They provide an opportunity to understand how the replacement of missing tissues from preexisting adult tissue is orchestrated at the molecular level. When amputated along any plane, planaria are capable of regenerating all missing tissue and rescaling all structures to the new size of the animal. Recently, rapid progress has been made in understanding the developmental pathways that control planarian regeneration. In particular Wnt/beta-catenin signaling is central in promoting posterior fates and inhibiting anterior identity. Currently the mechanisms that actively promote anterior identity remain unknown. Here, Smed-prep, encoding a TALE class homeodomain, is described as the first gene necessary for correct anterior fate and patterning during planarian regeneration. Smed-prep is expressed at high levels in the anterior portion of whole animals, and Smed-prep(RNAi leads to loss of the whole brain during anterior regeneration, but not during lateral regeneration or homeostasis in intact worms. Expression of markers of different anterior fated cells are greatly reduced or lost in Smed-prep(RNAi animals. We find that the ectopic anterior structures induced by abrogation of Wnt signaling also require Smed-prep to form. We use double knockdown experiments with the S. mediterranea ortholog of nou-darake (that when knocked down induces ectopic brain formation to show that Smed-prep defines an anterior fated compartment within which stem cells are permitted to assume brain fate, but is not required directly for this differentiation process. Smed-prep is the first gene clearly implicated as being necessary for promoting anterior fate and the first homeobox gene implicated in establishing positional identity during regeneration. Together our results suggest that Smed-prep is required in stem cell progeny as they form the anterior regenerative blastema and is

  1. The TALE class homeobox gene Smed-prep defines the anterior compartment for head regeneration.

    Science.gov (United States)

    Felix, Daniel A; Aboobaker, A Aziz

    2010-04-22

    Planaria continue to blossom as a model system for understanding all aspects of regeneration. They provide an opportunity to understand how the replacement of missing tissues from preexisting adult tissue is orchestrated at the molecular level. When amputated along any plane, planaria are capable of regenerating all missing tissue and rescaling all structures to the new size of the animal. Recently, rapid progress has been made in understanding the developmental pathways that control planarian regeneration. In particular Wnt/beta-catenin signaling is central in promoting posterior fates and inhibiting anterior identity. Currently the mechanisms that actively promote anterior identity remain unknown. Here, Smed-prep, encoding a TALE class homeodomain, is described as the first gene necessary for correct anterior fate and patterning during planarian regeneration. Smed-prep is expressed at high levels in the anterior portion of whole animals, and Smed-prep(RNAi) leads to loss of the whole brain during anterior regeneration, but not during lateral regeneration or homeostasis in intact worms. Expression of markers of different anterior fated cells are greatly reduced or lost in Smed-prep(RNAi) animals. We find that the ectopic anterior structures induced by abrogation of Wnt signaling also require Smed-prep to form. We use double knockdown experiments with the S. mediterranea ortholog of nou-darake (that when knocked down induces ectopic brain formation) to show that Smed-prep defines an anterior fated compartment within which stem cells are permitted to assume brain fate, but is not required directly for this differentiation process. Smed-prep is the first gene clearly implicated as being necessary for promoting anterior fate and the first homeobox gene implicated in establishing positional identity during regeneration. Together our results suggest that Smed-prep is required in stem cell progeny as they form the anterior regenerative blastema and is required for

  2. Gap Junctional Blockade Stochastically Induces Different Species-Specific Head Anatomies in Genetically Wild-Type Girardia dorotocephala Flatworms.

    Science.gov (United States)

    Emmons-Bell, Maya; Durant, Fallon; Hammelman, Jennifer; Bessonov, Nicholas; Volpert, Vitaly; Morokuma, Junji; Pinet, Kaylinnette; Adams, Dany S; Pietak, Alexis; Lobo, Daniel; Levin, Michael

    2015-11-24

    The shape of an animal body plan is constructed from protein components encoded by the genome. However, bioelectric networks composed of many cell types have their own intrinsic dynamics, and can drive distinct morphological outcomes during embryogenesis and regeneration. Planarian flatworms are a popular system for exploring body plan patterning due to their regenerative capacity, but despite considerable molecular information regarding stem cell differentiation and basic axial patterning, very little is known about how distinct head shapes are produced. Here, we show that after decapitation in G. dorotocephala, a transient perturbation of physiological connectivity among cells (using the gap junction blocker octanol) can result in regenerated heads with quite different shapes, stochastically matching other known species of planaria (S. mediterranea, D. japonica, and P. felina). We use morphometric analysis to quantify the ability of physiological network perturbations to induce different species-specific head shapes from the same genome. Moreover, we present a computational agent-based model of cell and physical dynamics during regeneration that quantitatively reproduces the observed shape changes. Morphological alterations induced in a genomically wild-type G. dorotocephala during regeneration include not only the shape of the head but also the morphology of the brain, the characteristic distribution of adult stem cells (neoblasts), and the bioelectric gradients of resting potential within the anterior tissues. Interestingly, the shape change is not permanent; after regeneration is complete, intact animals remodel back to G. dorotocephala-appropriate head shape within several weeks in a secondary phase of remodeling following initial complete regeneration. We present a conceptual model to guide future work to delineate the molecular mechanisms by which bioelectric networks stochastically select among a small set of discrete head morphologies. Taken together

  3. Gap Junctional Blockade Stochastically Induces Different Species-Specific Head Anatomies in Genetically Wild-Type Girardia dorotocephala Flatworms

    Directory of Open Access Journals (Sweden)

    Maya Emmons-Bell

    2015-11-01

    Full Text Available The shape of an animal body plan is constructed from protein components encoded by the genome. However, bioelectric networks composed of many cell types have their own intrinsic dynamics, and can drive distinct morphological outcomes during embryogenesis and regeneration. Planarian flatworms are a popular system for exploring body plan patterning due to their regenerative capacity, but despite considerable molecular information regarding stem cell differentiation and basic axial patterning, very little is known about how distinct head shapes are produced. Here, we show that after decapitation in G. dorotocephala, a transient perturbation of physiological connectivity among cells (using the gap junction blocker octanol can result in regenerated heads with quite different shapes, stochastically matching other known species of planaria (S. mediterranea, D. japonica, and P. felina. We use morphometric analysis to quantify the ability of physiological network perturbations to induce different species-specific head shapes from the same genome. Moreover, we present a computational agent-based model of cell and physical dynamics during regeneration that quantitatively reproduces the observed shape changes. Morphological alterations induced in a genomically wild-type G. dorotocephala during regeneration include not only the shape of the head but also the morphology of the brain, the characteristic distribution of adult stem cells (neoblasts, and the bioelectric gradients of resting potential within the anterior tissues. Interestingly, the shape change is not permanent; after regeneration is complete, intact animals remodel back to G. dorotocephala-appropriate head shape within several weeks in a secondary phase of remodeling following initial complete regeneration. We present a conceptual model to guide future work to delineate the molecular mechanisms by which bioelectric networks stochastically select among a small set of discrete head morphologies

  4. Modeling planarian regeneration: a primer for reverse-engineering the worm.

    Directory of Open Access Journals (Sweden)

    Daniel Lobo

    Full Text Available A mechanistic understanding of robust self-assembly and repair capabilities of complex systems would have enormous implications for basic evolutionary developmental biology as well as for transformative applications in regenerative biomedicine and the engineering of highly fault-tolerant cybernetic systems. Molecular biologists are working to identify the pathways underlying the remarkable regenerative abilities of model species that perfectly regenerate limbs, brains, and other complex body parts. However, a profound disconnect remains between the deluge of high-resolution genetic and protein data on pathways required for regeneration, and the desired spatial, algorithmic models that show how self-monitoring and growth control arise from the synthesis of cellular activities. This barrier to progress in the understanding of morphogenetic controls may be breached by powerful techniques from the computational sciences-using non-traditional modeling approaches to reverse-engineer systems such as planaria: flatworms with a complex bodyplan and nervous system that are able to regenerate any body part after traumatic injury. Currently, the involvement of experts from outside of molecular genetics is hampered by the specialist literature of molecular developmental biology: impactful collaborations across such different fields require that review literature be available that presents the key functional capabilities of important biological model systems while abstracting away from the often irrelevant and confusing details of specific genes and proteins. To facilitate modeling efforts by computer scientists, physicists, engineers, and mathematicians, we present a different kind of review of planarian regeneration. Focusing on the main patterning properties of this system, we review what is known about the signal exchanges that occur during regenerative repair in planaria and the cellular mechanisms that are thought to underlie them. By establishing an

  5. Identification and Actions of a Novel Third Maresin Conjugate in Tissue Regeneration: MCTR3.

    Science.gov (United States)

    Dalli, Jesmond; Sanger, Julia M; Rodriguez, Ana R; Chiang, Nan; Spur, Bernd W; Serhan, Charles N

    2016-01-01

    Maresin conjugates in tissue regeneration (MCTR) are a new family of evolutionarily conserved chemical signals that orchestrate host responses to promote tissue regeneration and resolution of infections. Herein, we identified the novel MCTR3 and established rank order potencies and matched the stereochemistries of MCTR1, MCTR2 and MCTR3 using material prepared by total organic synthesis and mediators isolated from both mouse and human systems. MCTR3 was produced from endogenous substrate by E. coli activated human macrophages and identified in sepsis patients. Each of the three synthetic MCTR dose-dependently (1-100 nM) accelerated tissue regeneration in planaria by 0.6-0.9 days. When administered at the onset or peak of inflammation, each of the MCTR promoted resolution of E. coli infections in mice. They increased bacterial phagocytosis by exudate leukocytes (~15-50%), limited neutrophil infiltration (~20-50%), promoted efferocytosis (~30%) and reduced eicosanoids. MCTR1 and MCTR2 upregulated human neutrophil and macrophage phagocytic responses where MCTR3 also proved to possess potent actions. These results establish the complete stereochemistry and rank order potencies for MCTR1, MCTR2 and MCTR3 that provide novel resolution moduli in regulating host responses to clear infections and promote tissue regeneration.

  6. WD60/FAP163 is a dynein intermediate chain required for retrograde intraflagellar transport in cilia.

    Science.gov (United States)

    Patel-King, Ramila S; Gilberti, Renée M; Hom, Erik F Y; King, Stephen M

    2013-09-01

    Retrograde intraflagellar transport (IFT) is required for assembly of cilia. We identify a Chlamydomonas flagellar protein (flagellar-associated protein 163 [FAP163]) as being closely related to the D1bIC(FAP133) intermediate chain (IC) of the dynein that powers this movement. Biochemical analysis revealed that FAP163 is present in the flagellar matrix and is actively trafficked by IFT. Furthermore, FAP163 copurified with D1bIC(FAP133) and the LC8 dynein light chain, indicating that it is an integral component of the retrograde IFT dynein. To assess the functional role of FAP163, we generated an RNA interference knockdown of the orthologous protein (WD60) in planaria. The Smed-wd60(RNAi) animals had a severe ciliary assembly defect that dramatically compromised whole-organism motility. Most cilia were present as short stubs that had accumulated large quantities of IFT particle-like material between the doublet microtubules and the membrane. The few remaining approximately full-length cilia had a chaotic beat with a frequency reduced from 24 to ∼10 Hz. Thus WD60/FAP163 is a dynein IC that is absolutely required for retrograde IFT and ciliary assembly.

  7. A planarian p53 homolog regulates proliferation and self-renewal in adult stem cell lineages.

    Science.gov (United States)

    Pearson, Bret J; Sánchez Alvarado, Alejandro

    2010-01-01

    The functions of adult stem cells and tumor suppressor genes are known to intersect. However, when and how tumor suppressors function in the lineages produced by adult stem cells is unknown. With a large population of stem cells that can be manipulated and studied in vivo, the freshwater planarian is an ideal system with which to investigate these questions. Here, we focus on the tumor suppressor p53, homologs of which have no known role in stem cell biology in any invertebrate examined thus far. Planaria have a single p53 family member, Smed-p53, which is predominantly expressed in newly made stem cell progeny. When Smed-p53 is targeted by RNAi, the stem cell population increases at the expense of progeny, resulting in hyper-proliferation. However, ultimately the stem cell population fails to self-renew. Our results suggest that prior to the vertebrates, an ancestral p53-like molecule already had functions in stem cell proliferation control and self-renewal.

  8. SMED-TLX-1 (NR2E1) is critical for tissue and body plan maintenance in Schmidtea mediterranea in fasting/feeding cycles.

    Science.gov (United States)

    Raška, O; Kostrouchová, V; Behenský, F; Yilma, P; Saudek, V; Kostrouch, Z; Kostrouchová, M

    2011-01-01

    Nuclear receptors (NRs), or nuclear hormone receptors (NHRs), are transcription factors that regulate development and metabolism of most if not all animal species. Their regulatory networks include conserved mechanisms that are shared in-between species as well as mechanisms that are restricted to certain phyla or even species. In search for conserved members of the NHR family in Schmidtea mediterranea, we identified a molecular signature of a class of NRs, NR2E1, in the S. mediterranea genome and cloned its complete cDNA coding sequence. The derived amino acid sequence shows a high degree of conservation of both DNA-binding domain and ligand- binding domain and a remarkably high homology to vertebrate NR2E1 and C. elegans NHR-67. Quantitative PCR detected approximately ten-fold higher expression of Smed-tlx-1 in the proximal part of the head compared to the tail region. The expression of Smed-tlx-1 is higher during fed state than during fasting. Smed-tlx-1 down-regulation by RNA interference affects the ability of the animals to maintain body plan and induces defects of brain, eyes and body shape during fasting and re-growing cycles. These results suggest that SMED-TLX-1 is critical for tissue and body plan maintenance in planaria.

  9. Toxicity of a hazardous chemical mixture in the planarian, Dugesia dorotocephala

    Energy Technology Data Exchange (ETDEWEB)

    Ramsdell, H.S.; Matthews, C.M. [Colorado State Univ., Ft. Collins, CO (United States)

    1995-12-31

    The responses of the planarian, Dugesia dorotocephala to toxic chemical mixtures representative of water contaminants associated with hazardous waste sites have been studied in laboratory experiments. These free-living flatworms are readily maintained under laboratory conditions and are a useful invertebrate model for toxicology studies. Their widespread occurrence also makes them potentially useful for environmental studies. Mature asexual Dugesia dorotocephala were exposed for 14 days to mixtures of seven contaminants frequently detected in water at hazardous waste sites. The complete 1X mixture contained both metals (As, 3.1 ppm; Cr, 0.7 ppm; Pb, 3.7 ppm) and organics (chloroform, 1.5 ppm; benzene, 5.0 ppm; phenol, 3.4 ppm; trichloroethylene, 3.8 ppm). Groups of planaria were treated with the complete mixture at 0.1X, 1X and 10X concentrations. Additional groups were exposed to the metals-only or organics-only submixtures, also at 0.1X, 1X and 10X concentrations. Treatment solutions were renewed daily. Suppression of fissioning was observed in all of the 1X and 10X treatment groups. Significant mortality occurred only in the 10X complete and 1 0X metals-only treatments. It appears that the toxic effects of the complete mixture are primarily associated with the metal components.

  10. WD60/FAP163 is a dynein intermediate chain required for retrograde intraflagellar transport in cilia

    Science.gov (United States)

    Patel-King, Ramila S.; Gilberti, Renée M.; Hom, Erik F. Y.; King, Stephen M.

    2013-01-01

    Retrograde intraflagellar transport (IFT) is required for assembly of cilia. We identify a Chlamydomonas flagellar protein (flagellar-associated protein 163 [FAP163]) as being closely related to the D1bIC(FAP133) intermediate chain (IC) of the dynein that powers this movement. Biochemical analysis revealed that FAP163 is present in the flagellar matrix and is actively trafficked by IFT. Furthermore, FAP163 copurified with D1bIC(FAP133) and the LC8 dynein light chain, indicating that it is an integral component of the retrograde IFT dynein. To assess the functional role of FAP163, we generated an RNA interference knockdown of the orthologous protein (WD60) in planaria. The Smed-wd60(RNAi) animals had a severe ciliary assembly defect that dramatically compromised whole-organism motility. Most cilia were present as short stubs that had accumulated large quantities of IFT particle–like material between the doublet microtubules and the membrane. The few remaining approximately full-length cilia had a chaotic beat with a frequency reduced from 24 to ∼10 Hz. Thus WD60/FAP163 is a dynein IC that is absolutely required for retrograde IFT and ciliary assembly. PMID:23864713

  11. Spot the difference: Solving the puzzle of hidden pictures in the lizard genome for identification of regeneration factors

    Science.gov (United States)

    Chung, Jin Woong

    2016-01-01

    All living things share some common life processes, such as growth and reproduction, and have the ability to respond to their environment. However, each type of organism has its own specialized way of managing biological events. Genetic sequences determine phenotypic and physiological traits. Based on genetic information, comparative genomics has been used to delineate the differences and similarities between various genomes, and significant progress has been made in understanding regenerative biology by comparing the genomes of a variety of lower animal models of regeneration, such as planaria, zebra fish, and newts. However, the genome of lizards has been relatively ignored until recently, even though lizards have been studied as an excellent amniote model of tissue regeneration. Very recently, whole genome sequences of lizards have been uncovered, and several attempts have been made to find regeneration factors based on genetic information. In this article, recent advances in comparative analysis of the lizard genome are introduced, and their biological implications and putative applications for regenerative medicine and stem cell biology are discussed. [BMB Reports 2016; 49(5): 249-254] PMID:26949021

  12. The DDX3 subfamily of the DEAD box helicases: divergent roles as unveiled by studying different organisms and in vitro assays.

    Science.gov (United States)

    Rosner, A; Rinkevich, B

    2007-01-01

    DDX3 (or Ded1p), the highly conserved subfamily of the DEAD-box RNA helicase family (40 members in humans), plays important roles in RNA metabolism. DDX3X and DDX3Y, the two human paralogous genes of this subfamily of proteins, have orthologous candidates in a diverse range of eukaryotes, from yeast and plants to animals. While DDX3Y, which is essential for normal spermatogenesis, is translated only in the testes, DDX3X protein is ubiquitously expressed, involved in RNA transcription, RNA splicing, mRNA transport, translation initiation and cell cycle regulation. Studies of recent years have revealed that DDX3X participates in HIV and hepatitis C viral infections, and in hepatocellular carcinoma, a complication of hepatitis B and hepatitis C infections. In the urochordates (i.e., Botryllus schlosseri) and in diverse invertebrate phyla (represented by model organisms such as: Drosophila, Hydra, Planaria), DDX3 proteins (termed also PL10) are involved in developmental pathways, highly expressed in adult undifferentiated soma and germ cells and in some adult and embryo's differentiating tissues. As the mechanistic and functional knowledge of DDX3 proteins is limited, we suggest assembling the available data on DDX3 proteins, from all studied organisms and in vitro assays, depicting a unified mechanistic scheme for DDX3 proteins' functions. Understanding the diverse functions of DDX3 in multicellular organisms may be particularly important for effective strategies of drug design.

  13. Common mechanics of mode switching in locomotion of limbless and legged animals.

    Science.gov (United States)

    Kuroda, Shigeru; Kunita, Itsuki; Tanaka, Yoshimi; Ishiguro, Akio; Kobayashi, Ryo; Nakagaki, Toshiyuki

    2014-06-06

    Crawling using muscular waves is observed in many species, including planaria, leeches, nemertea, aplysia, snails, chitons, earthworms and maggots. Contraction or extension waves propagate along the antero-posterior axis of the body as the crawler pushes the ground substratum backward. However, the observation that locomotory waves can be directed forward or backward has attracted much attention over the past hundred years. Legged organisms such as centipedes and millipedes exhibit parallel phenomena; leg tips form density waves that propagate backward or forward. Mechanical considerations reveal that leg-density waves play a similar role to locomotory waves in limbless species, and that locomotory waves are used by a mechanism common to both legged and limbless species to achieve crawling. Here, we report that both mode switching of the wave direction and friction control were achieved when backward motion was induced in the laboratory. We show that the many variations of switching in different animals can essentially be classified in two types according to mechanical considerations. We propose that during their evolution, limbless crawlers first moved in a manner similar to walking before legs were obtained. Therefore, legged crawlers might have learned the mechanical mode of movement involved in walking long before obtaining legs.

  14. Embryonic development of Girardia tigrina (Girard, 1850) (Platyhelminthes, Tricladida, Paludicola).

    Science.gov (United States)

    Vara, D C; Leal-Zanchet, A M; Lizardo-Daudt, H m

    2008-11-01

    The embryonic development of freshwater triclads is mainly known from studies of species of Dendrocoelum, Planaria, Polycelis, and, more recently, Schmidtea. The present study characterizes the development of Girardia tigrina (Girard, 1850) by means of optical microcopy using glycol methacrylate semi-thin sections. 94 cocoons were collected in the period from laying to hatching, with intervals of up to twenty-four hours. The sequence of morphological changes occurring in the embryo permitted the identification of nine embryonic stages. At the time of cocoon laying, numerous embryos were dispersed among many yolk cells, with a rigid capsule covering the entire cocoon. In the first stage (approx. up to 6 hours after cocoon laying), yolk cells and embryonic cells showed random distribution. Stage II (between 12 and 24 hours after cocoon laying) is characterized by aggregates of blastomeres, which later aggregate forming an enteroblastula. Approximately 2 days after cocoon laying (stage III), formation of the embryonic epidermis and embryonic digestive system took place, the latter degenerating during the subsequent stage. Stage V (until the fourth day) is characterized by the formation of the definitive epidermis. Between 4 and 6 days after laying, organogenesis of the definitive inner organs starts (stage VI). Approximately 14 days after laying (stage IX), formation of the nervous system is completed. At this stage, the embryo shows similar characteristics to those of newly hatched juveniles. The hatching of Girardia tigrina occurs in the period between twelve to twenty-two days after cocoon laying.

  15. Spot the difference: Solving the puzzle of hidden pictures in the lizard genome for identification of regeneration factors.

    Science.gov (United States)

    Chung, Jin Woong

    2016-05-01

    All living things share some common life processes, such as growth and reproduction, and have the ability to respond to their environment. However, each type of organism has its own specialized way of managing biological events. Genetic sequences determine phenotypic and physiological traits. Based on genetic information, comparative genomics has been used to delineate the differences and similarities between various genomes, and significant progress has been made in understanding regenerative biology by comparing the genomes of a variety of lower animal models of regeneration, such as planaria, zebra fish, and newts. However, the genome of lizards has been relatively ignored until recently, even though lizards have been studied as an excellent amniote model of tissue regeneration. Very recently, whole genome sequences of lizards have been uncovered, and several attempts have been made to find regeneration factors based on genetic information. In this article, recent advances in comparative analysis of the lizard genome are introduced, and their biological implications and putative applications for regenerative medicine and stem cell biology are discussed. [BMB Reports 2016; 49(5): 249-254].

  16. Dynamics of asexual reproduction in planarians

    Science.gov (United States)

    Schoetz, Eva-Maria; Lincoln, Bryan; Quinodoz, Sofia

    2011-03-01

    Planaria research is experiencing a resurgence due to the development of molecular tools, the Planarian genome project and database resources. Despite the resulting progress in planarian biology research, an extensive study of their physical properties remains to be undertaken. We developed a method to collect a large amount of data on the dynamics of clonal reproduction in the freshwater planarian S.mediterranea. The capability of planarians to regenerate an entire organism from a minuscule body part is based on a homogeneously distributed stem cell population that comprises 25-30% of all cells. Due to this stem cell contingent, planarians can reproduce spontaneously by dividing into a larger head and a smaller tail piece, which then will rebuild the missing body parts, including a central nervous system, within about a week. Time-lapse imaging allows us to characterize the fission process in detail, revealing the stages of the process as well as capturing the nature of the rupture itself. A traction force measurement setup is being developed to allow us to quantify the forces planarians exert on the substrate during reproduction, a macroscopic analog to the Traction Force Microscopy setups used to determine local cellular forces. We are particularly interested in the molecular processes during division and the interplay between tissue mechanics and cell signaling.

  17. Complete genome sequence of a novel extrachromosomal virus-like element identified in planarian Girardia tigrina

    Directory of Open Access Journals (Sweden)

    Vagner Loura L

    2002-06-01

    Full Text Available Abstract Background Freshwater planarians are widely used as models for investigation of pattern formation and studies on genetic variation in populations. Despite extensive information on the biology and genetics of planaria, the occurrence and distribution of viruses in these animals remains an unexplored area of research. Results Using a combination of Suppression Subtractive Hybridization (SSH and Mirror Orientation Selection (MOS, we compared the genomes of two strains of freshwater planarian, Girardia tigrina. The novel extrachromosomal DNA-containing virus-like element denoted PEVE (Planarian Extrachromosomal Virus-like Element was identified in one planarian strain. The PEVE genome (about 7.5 kb consists of two unique regions (Ul and Us flanked by inverted repeats. Sequence analyses reveal that PEVE comprises two helicase-like sequences in the genome, of which the first is a homolog of a circoviral replication initiator protein (Rep, and the second is similar to the papillomavirus E1 helicase domain. PEVE genome exists in at least two variant forms with different arrangements of single-stranded and double-stranded DNA stretches that correspond to the Us and Ul regions. Using PCR analysis and whole-mount in situ hybridization, we characterized PEVE distribution and expression in the planarian body. Conclusions PEVE is the first viral element identified in free-living flatworms. This element differs from all known viruses and viral elements, and comprises two potential helicases that are homologous to proteins from distant viral phyla. PEVE is unevenly distributed in the worm body, and is detected in specific parenchyma cells.

  18. Generation of Mice with Hepatocyte-Specific Conditional Deletion of Notum.

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    Frédéric Canal

    Full Text Available Fine tuning of the Wnt/β-catenin signaling pathway is essential for the proper development and function of the liver. Aberrant activation of this pathway is observed in 20%-40% of hepatocellular carcinomas (HCC. Notum encodes a secreted Wnt deacylase that inhibits Wnt activity and thereby restricts the zone of activation of Wnt/β-catenin signaling. An important role of NOTUM has been described in development in drosophila, planaria and zebrafish, but its role in the mammalian liver is unknown. Notum is required for spatial control of the Wnt/β-catenin signaling in several animal models and the Wnt/β-catenin pathway contributes to liver patterning involved in metabolic zonation. Therefore, Notum may be involved in the liver patterning induced by the Wnt/β-catenin signaling during the adult stage.We generated a conditional Notum knockout mouse mutant to study the effect of the deletion of Notum in the liver. We show that Notum is a direct target of the Wnt/β-catenin signaling in the liver. Liver-specific deletion of Notum did not modify liver zonation, but Notum deletion had a long-term effect on mouse physiology. In particular, male mutant mice developed metabolic disorders.We show that Notum is not a key actor of Wnt/β-catenin-dependent liver patterning of adult mice, but has role in liver glucose homeostasis. Male mice deficient in Notum specifically in the liver develop metabolic dysfunctions implicating Notum in the development of Type 2 diabetes.

  19. A second-generation device for automated training and quantitative behavior analyses of molecularly-tractable model organisms.

    Directory of Open Access Journals (Sweden)

    Douglas Blackiston

    Full Text Available A deep understanding of cognitive processes requires functional, quantitative analyses of the steps leading from genetics and the development of nervous system structure to behavior. Molecularly-tractable model systems such as Xenopus laevis and planaria offer an unprecedented opportunity to dissect the mechanisms determining the complex structure of the brain and CNS. A standardized platform that facilitated quantitative analysis of behavior would make a significant impact on evolutionary ethology, neuropharmacology, and cognitive science. While some animal tracking systems exist, the available systems do not allow automated training (feedback to individual subjects in real time, which is necessary for operant conditioning assays. The lack of standardization in the field, and the numerous technical challenges that face the development of a versatile system with the necessary capabilities, comprise a significant barrier keeping molecular developmental biology labs from integrating behavior analysis endpoints into their pharmacological and genetic perturbations. Here we report the development of a second-generation system that is a highly flexible, powerful machine vision and environmental control platform. In order to enable multidisciplinary studies aimed at understanding the roles of genes in brain function and behavior, and aid other laboratories that do not have the facilities to undergo complex engineering development, we describe the device and the problems that it overcomes. We also present sample data using frog tadpoles and flatworms to illustrate its use. Having solved significant engineering challenges in its construction, the resulting design is a relatively inexpensive instrument of wide relevance for several fields, and will accelerate interdisciplinary discovery in pharmacology, neurobiology, regenerative medicine, and cognitive science.

  20. Recent evidence for evolution of the genetic code

    Science.gov (United States)

    Osawa, S.; Jukes, T. H.; Watanabe, K.; Muto, A.

    1992-01-01

    The genetic code, formerly thought to be frozen, is now known to be in a state of evolution. This was first shown in 1979 by Barrell et al. (G. Barrell, A. T. Bankier, and J. Drouin, Nature [London] 282:189-194, 1979), who found that the universal codons AUA (isoleucine) and UGA (stop) coded for methionine and tryptophan, respectively, in human mitochondria. Subsequent studies have shown that UGA codes for tryptophan in Mycoplasma spp. and in all nonplant mitochondria that have been examined. Universal stop codons UAA and UAG code for glutamine in ciliated protozoa (except Euplotes octacarinatus) and in a green alga, Acetabularia. E. octacarinatus uses UAA for stop and UGA for cysteine. Candida species, which are yeasts, use CUG (leucine) for serine. Other departures from the universal code, all in nonplant mitochondria, are CUN (leucine) for threonine (in yeasts), AAA (lysine) for asparagine (in platyhelminths and echinoderms), UAA (stop) for tyrosine (in planaria), and AGR (arginine) for serine (in several animal orders) and for stop (in vertebrates). We propose that the changes are typically preceded by loss of a codon from all coding sequences in an organism or organelle, often as a result of directional mutation pressure, accompanied by loss of the tRNA that translates the codon. The codon reappears later by conversion of another codon and emergence of a tRNA that translates the reappeared codon with a different assignment. Changes in release factors also contribute to these revised assignments. We also discuss the use of UGA (stop) as a selenocysteine codon and the early history of the code.

  1. Recent evidence for evolution of the genetic code

    Science.gov (United States)

    Osawa, S.; Jukes, T. H.; Watanabe, K.; Muto, A.

    1992-01-01

    The genetic code, formerly thought to be frozen, is now known to be in a state of evolution. This was first shown in 1979 by Barrell et al. (G. Barrell, A. T. Bankier, and J. Drouin, Nature [London] 282:189-194, 1979), who found that the universal codons AUA (isoleucine) and UGA (stop) coded for methionine and tryptophan, respectively, in human mitochondria. Subsequent studies have shown that UGA codes for tryptophan in Mycoplasma spp. and in all nonplant mitochondria that have been examined. Universal stop codons UAA and UAG code for glutamine in ciliated protozoa (except Euplotes octacarinatus) and in a green alga, Acetabularia. E. octacarinatus uses UAA for stop and UGA for cysteine. Candida species, which are yeasts, use CUG (leucine) for serine. Other departures from the universal code, all in nonplant mitochondria, are CUN (leucine) for threonine (in yeasts), AAA (lysine) for asparagine (in platyhelminths and echinoderms), UAA (stop) for tyrosine (in planaria), and AGR (arginine) for serine (in several animal orders) and for stop (in vertebrates). We propose that the changes are typically preceded by loss of a codon from all coding sequences in an organism or organelle, often as a result of directional mutation pressure, accompanied by loss of the tRNA that translates the codon. The codon reappears later by conversion of another codon and emergence of a tRNA that translates the reappeared codon with a different assignment. Changes in release factors also contribute to these revised assignments. We also discuss the use of UGA (stop) as a selenocysteine codon and the early history of the code.

  2. Novel proresolving and tissue-regenerative resolvin and protectin sulfido-conjugated pathways

    Science.gov (United States)

    Dalli, Jesmond; Ramon, Sesquile; Norris, Paul C.; Colas, Romain A.; Serhan, Charles N.

    2015-01-01

    Local mediators orchestrate the host response to both sterile and infectious challenge and resolution. Recent evidence demonstrates that maresin sulfido-conjugates actively resolve acute inflammation and promote tissue regeneration. In this report, we investigated self-limited infectious exudates for novel bioactive chemical signals in tissue regeneration and resolution. By use of spleens from Escherichia coli infected mice, self-resolving infectious exudates, human spleens, and blood from patients with sepsis, we identified 2 new families of potent molecules. Characterization of their physical properties and isotope tracking demonstrated that the bioactive structures contained a docosahexaenoate backbone and sulfido-conjugated triene or tetraene double-bond systems. Activated human phagocytes converted 17-hydro(peroxy)-4Z,7Z,10Z,13Z,15E,19Z-docosahexaenoic acid to these bioactive molecules. Regeneration of injured planaria was accelerated with nanomolar amounts of 16-glutathionyl, 17-hydroxy-4Z,7Z,10,12,14,19Z-docosahexaenoic acid and 16-cysteinylglycinyl, 17-hydroxy-4Z,7Z,10,12,14,19Z-docosahexaenoic acid (Protectin sulfido-conjugates) or 8-glutathionyl, 7,17-dihydroxy-4Z,9,11,13Z,15E,19Z-docosahexaenoic acid and 8-cysteinylglycinyl, 7,17-dihydroxy-4Z,9,11,13Z,15E,19Z-docosahexaenoic acid (Resolvin sulfido-conjugates). Each protectin and resolvin sulfido-conjugate dose dependently (0.1–10 nM) stimulated human macrophage bacterial phagocytosis, phagolysosomal acidification, and efferocytosis. Together, these results identify 2 novel pathways and provide evidence for structural elucidation of new resolution moduli. These resolvin and protectin conjugates identified in mice and human infected tissues control host responses promoting catabasis.—Dalli, J., Ramon, S., Norris, P. C., Colas, R. A., Serhan, C. N. Novel proresolving and tissue-regenerative resolvin and protectin sulfido-conjugated pathways. PMID:25713027

  3. Theoretical computer science and the natural sciences

    Science.gov (United States)

    Marchal, Bruno

    2005-12-01

    I present some fundamental theorems in computer science and illustrate their relevance in Biology and Physics. I do not assume prerequisites in mathematics or computer science beyond the set N of natural numbers, functions from N to N, the use of some notational conveniences to describe functions, and at some point, a minimal amount of linear algebra and logic. I start with Cantor's transcendental proof by diagonalization of the non enumerability of the collection of functions from natural numbers to the natural numbers. I explain why this proof is not entirely convincing and show how, by restricting the notion of function in terms of discrete well defined processes, we are led to the non algorithmic enumerability of the computable functions, but also-through Church's thesis-to the algorithmic enumerability of partial computable functions. Such a notion of function constitutes, with respect to our purpose, a crucial generalization of that concept. This will make easy to justify deep and astonishing (counter-intuitive) incompleteness results about computers and similar machines. The modified Cantor diagonalization will provide a theory of concrete self-reference and I illustrate it by pointing toward an elementary theory of self-reproduction-in the Amoeba's way-and cellular self-regeneration-in the flatworm Planaria's way. To make it easier, I introduce a very simple and powerful formal system known as the Schoenfinkel-Curry combinators. I will use the combinators to illustrate in a more concrete way the notion introduced above. The combinators, thanks to their low-level fine grained design, will also make it possible to make a rough but hopefully illuminating description of the main lessons gained by the careful observation of nature, and to describe some new relations, which should exist between computer science, the science of life and the science of inert matter, once some philosophical, if not theological, hypotheses are made in the cognitive sciences. In the

  4. Ethanol and cocaine: environmental place conditioning, stereotypy, and synergism in planarians.

    Science.gov (United States)

    Tallarida, Christopher S; Bires, Kristopher; Avershal, Jacob; Tallarida, Ronald J; Seo, Stephanie; Rawls, Scott M

    2014-09-01

    More than 90% of individuals who use cocaine also report concurrent ethanol use, but only a few studies, all conducted with vertebrates, have investigated pharmacodynamic interactions between ethanol and cocaine. Planaria, a type of flatworm often considered to have the simplest 'brain,' is an invertebrate species especially amenable to the quantification of drug-induced behavioral responses and identification of conserved responses. Here, we investigated stereotypical and environmental place conditioning (EPC) effects of ethanol administered alone and in combination with cocaine. Planarians displayed concentration-related increases in C-shaped movements following exposure to ethanol (0.01-1%) (maximal effect: 9.9±1.1 C-shapes/5 min at 0.5%) or cocaine (0.1-5 mM) (maximal effect: 42.8±4.1 C-shapes/5 min at 5 mM). For combined administration, cocaine (0.1-5 mM) was tested with submaximal ethanol concentrations (0.01, 0.1%); the observed effect for the combination was enhanced compared to its predicted effect, indicating synergism for the interaction. The synergy with ethanol was specific for cocaine, as related experiments revealed that combinations of ethanol and nicotine did not result in synergy. For EPC experiments, ethanol (0.0001-1%) concentration-dependently increased EPC, with significant environmental shifts detected at 0.01 and 1%. Cocaine (0.001-1 μM) produced an inverted U-shaped concentration-effect curve, with a significant environmental shift observed at 0.01 μM. For combined exposure, variable cocaine concentrations (0.001-1 μM) were administered with a statistically ineffective concentration of ethanol (0.0001%). For each concentration of cocaine, the environmental shift was enhanced by ethanol, with significance detected at 1 μM. Cocaethylene, a metabolite of cocaine and ethanol, also produced C-shapes and EPC. Lidocaine (0.001-10 μM), an anesthetic and analog of cocaine, did not produce EPC or C-shaped movements. Evidence from planarians

  5. The use of invertebrates as indicators of environmental change in alpine rivers and lakes

    Energy Technology Data Exchange (ETDEWEB)

    Khamis, K.; Hannah, D.M. [School of Geography Earth and Environmental Science, University of Birmingham, Birmingham B15 2TT (United Kingdom); Brown, L.E. [School of Geography/water@leeds, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom); Tiberti, R. [DSTA, Dipartimento di Scienze della Terra e dell' Ambiente, University of Pavia, Via Ferrata 9, 27100 Pavia (Italy); Alpine Wildlife Research Centre, Gran Paradiso National Park, Degioz 11, I-1101 Valsavarenche, Aosta (Italy); Milner, A.M., E-mail: a.m.milner@bham.ac.uk [School of Geography Earth and Environmental Science, University of Birmingham, Birmingham B15 2TT (United Kingdom); Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775 (United States)

    2014-09-15

    In alpine regions climatic change will alter the balance between water sources (rainfall, ice-melt, snowmelt, and groundwater) for aquatic systems, particularly modifying the relative contributions of meltwater, groundwater and rain to both rivers and lakes. While these changes are expected to have implications for alpine aquatic ecosystems, little is known about potential ecological tipping points and associated indicator taxa. We examined changes in biotic communities along a gradient of glacier influence for two study systems: (1) a stream network in the French Pyrénées; and (2) a network of lakes in the Italian Alps, with the aim of identifying potential indicator taxa (macroinvertebrates and zooplankton) of glacier retreat in these environments. To assess parallels in biotic responses across streams and lakes, both primary data and findings from other publications were synthesised. Using TITAN (Threshold Indicator Taxa ANalysis) changes in community composition of river taxa were identified at thresholds of < 5.1% glacier cover and < 66.6% meltwater contribution. Below these thresholds the loss of cold stenothermic benthic invertebrate taxa, Diamesa spp. and the Pyrenean endemic Rhyacophila angelieri was apparent. Some generalist taxa including Protonemura sp., Perla grandis, Baetis alpinus, Rhithrogena loyolaea and Microspectra sp. increased when glacier cover was < 2.7% and < 52% meltwater. Patterns were not as distinct for the alpine lakes, due to fewer sampling sites; however, Daphnia longispina grp. and the benthic invertebrate groups Plectopera and Planaria were identified as potential indicator taxa. While further work is required to assess potential indicator taxa for alpine lake systems, findings from alpine river systems were consistent between methods for assessing glacier influence (meltwater contribution/glacier cover). Hence, it is clear that TITAN could become a useful management tool, enabling: (i) the identification of taxa particularly

  6. 器官形态发生探索Ⅰ:生物电与形态发生%Exploration of organ morphogenesis Ⅰ:Bioelectricity and morphogenesis

    Institute of Scientific and Technical Information of China (English)

    赵海平; 刘振; 陈广信; 李春义

    2015-01-01

    Summary Morphogenesis is a biological process that involves the shape development and pattern maintenance of an organism . Morphogenetic information is needed for morphogenetic primordial developing to construct an appropriate three‐dimension (3D) structure , which includes three aspects :positional information , prepatterning information , and epigenetic information . The essence and mechanism of morphogenetic information is the primary condition to understand morphogenesis . This paper reviews the latest research progress of morphogenetic field , bioelectricity and organ morphogenesis . Mechanism of organ morphogenesis has not been well understood in life science field . Advances in molecular biology were expected to solve this mystery , but proved to be a failure . Interestingly , recent study showed that organ morphogenesis was regulated by bioelectricity at multiple levels on lower animals , for example:1) Artificially setting the resting potential in embryonic frog cells can lead to eye formation at any part of amphibian body ;2) bioelectricity can regulate regeneration of tail and ectopic limb formation in Xenopus tadpoles ;3) bioelectricity determines regeneration pattern of amputated planaria fragments on whether head or tail . Therefore , organ fate was obviously determined by bioelectric state of morphogenetic primordia . Bioelectricity is the essence of organ morphogenetic information , which is a landmark advance in this field that the bioelectricity encodes organ morphogenesis . It is an inspiration that electric is used as a signal code in communication for understanding work mechanism of bioelectric code . For example , Morse alphabet and binary , which consist of electrical signal , are used in telegram system and computer system respectively . Nowadays , 3D structures can be made by 3D printer , and the machine can execute commands encoded by binary . The physical process of bioelectricity encoding organ morphogenesis in animal bodies is

  7. Redescripción y algunos aspectos ecológicos de Girardia tigrina, G. cameliae y G. paramensis (Dugesiidae, Tricladida en Antioquia, Colombia Redescription and some ecological aspects of Girardia tigrina, G. cameliae y G. paramensis (Dugesiidae, Tricladida in Antioquia, Colombia

    Directory of Open Access Journals (Sweden)

    Mauricio A Muñoz

    2007-12-01

    Full Text Available Turbellaria está integrada por 2 órdenes: Catenulida y Rhabditophora. Dentro del último, el suborden Paludicola comprende las familias Dendrocoelidae, Dugesiidae y Planariidae. En este estudio fueron encontradas: Girardia cameliae, G. paramensis y G. tigrina (Dugesiidae. Fueron analizados 22 sistemas acuáticos (captura manual en zonas de remanso del centro y sur oriente de Antioquia. En 3 individuos por especie, se hizo descripción de: ancho, longitud y color corporal; forma y tamaño de cabeza; posición auricular; distancia entre manchas oculares; longitud y posición de faringe. Se efectuó análisis histológico de: gonoporo; bulbo, papila, glándulas y lúmen peneal; vesículas seminales y vasos deferentes; atrio masculino; testículos; canal bursal y bolsa copuladora; ovario y oviductos; glándulas de la cáscara. Se midieron: oxigeno disuelto, pH, conductividad y dureza en el agua. Se realizó reconstrucción gráfica de órganos reproductivos (caracteres taxonómicos en cortes histológicos seriados. G. tigrina y G. paramensis, presentaron amplia distribución geográfica. Estas especies consumieron ex situ: Daphnia pulex, Chironomus sp., Culex sp. y Drosophila sp. (estados larvales. Tales planarias prefirieron aguas clase II y III (según BMWP/Col. Los aspectos físicos y químicos no exhibieron diferencias entre las preferencias de las especies. G. cameliae se encontró en una sola localidad en condiciones particulares.The Turbellaria comprises 2 orders: Catenulida and Rhabditophora. In the latter, the suborder Paludicola contains the families Dendrocoelidae, Dugesiidae and Planariidae. In this study, we found Girardia cameliae, Girardia paramensis and Giardia tigrina (Dugesiidae in 22 aquatic systems using manual capture in river ponds zones of central and southeastern Antioquia. In 3 individuals per species, a description of: corporal color, length, and wide; head form and size; auricles position; intraocular distance; pharynx

  8. The Study of DNA Damage by Pb2+ and Cd2 + in Dugesia japonica and Damage Repair%Pb2+和Cd2+对日本三角涡虫DNA损伤及损伤后修复的研究

    Institute of Scientific and Technical Information of China (English)

    彭莹; 李亚男; 黄原; 叶海燕

    2012-01-01

    以日本三角涡虫(Dugesia japonica)为实验材料,采用急性毒性实验研究Pb2+、Cd2+胁迫下日本三角涡虫体细胞DNA损伤情况以及绿豆浸出液对DNA损伤的保护和修复机制.采用浓度为120 mg/L的Pb(NO3)2和1 mg/L的CdCl2溶液分别处理涡虫,紫外分光光度法和琼脂糖凝胶电泳检测24h后三角涡虫DNA损伤情况.同时增加由绿豆浸出液进行修复的2组对照以研究绿豆对于DNA重金属损伤后的修复作用和效果.结果表明,Pb2+、Cd2胁迫使日本三角涡虫DNA交联程度增加,并引起DNA链的断裂;绿豆浸出液对于由Cd2+胁迫引起的DNA损伤修复作用较好.而对于Pb2+胁迫,在绿豆浸出液与Pb2同时培养的对照组中,推测该浸出液可能使Pb2+形成沉淀从而减小Pb2+浓度,因此使DNA损伤修复具有较好效果,对已经由Pb2+胁迫造成损伤的DNA,修复作用不大.%We used technology of Ultraviolet Spectrophotometry and Agarose Gel Electrophoresis to analyze DNA damage under Pb2+ and Cd2+ stress in Dugesia japonica' somatic cell, and DNA damage repair by lixivium of green beans. The concentration of Pb2+ and Cd2+ were respectively120 mg/L (Pb(NO3)2) and 1 mg/L (CdCl2). We also added control groups with lixivium of green beans to repair the damaged DNA. Planaria were exposed to 24 hours and extracted using method of Proteinase K . Though the analysis of experimental data. The results show that Lead and cadmium can induce DNA-DNA cross-linking and cut the DNA into smaller snippet. It had a better effect with the lixivium of green beans for damage repair caused by Cd2+ stress. For DNA damage caused by Pb2* stress, it also had a better effect if we added the green beans lixivium at the same time with Pb (NO3)2 The reason is probable because the lixivium can precipitate Pb2+. But in control group which we added the lixivium after damage, there had not repairable effect in DNA damage.