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Sample records for mediterranean ascidian ciona

  1. Delineating metamorphic pathways in the ascidian Ciona intestinalis.

    PubMed

    Nakayama-Ishimura, Akie; Chambon, Jean-phillippe; Horie, Takeo; Satoh, Nori; Sasakura, Yasunori

    2009-02-15

    In most ascidians, metamorphosis of tadpole-like swimming larvae is accompanied by dynamic changes in their shape to form sessile adults. The mechanisms underlying ascidian metamorphosis have been debated for a long time. Although recent molecular studies have revealed the presence of various molecules involving in this process, the basic mechanism of the metamorphic events is still unclear. For example, it has not been solved whether all metamorphic events are organized by the same single pathway or by multiple, independent pathways. In the present study, we approached this question using the ascidian Ciona intestinalis. When the papillae and preoral lobes of the larvae were cut off, the papillae-cut larvae initiated certain trunk metamorphic events such as the formation of an ampulla, body axis rotation and adult organ growth without other metamorphic events. This observation indicates that metamorphic events can be divided into at least two groups, events initiated in the papillae-cut larva and events not initiated in this larva. In addition to this observation, we have isolated a novel mutant, tail regression failed (trf), which shows similar phenotypes to those of papillae-cut larvae. The phenotypes of trf mutants are basically different from those of swimming juvenile mutants (Sasakura, Y., Nakashima, K., Awazu, S., Matsuoka, T., Nakayama, A., Azuma, J., Satoh, N., 2005. Transposon-mediated insertional mutagenesis revealed the functions of animal cellulose synthase in the ascidian Ciona intestinalis. Proc. Natl. Acad. Sci. U. S. A. 102, 15134-15139.), which also show abnormal metamorphosis. These findings suggest a model by which ascidian metamorphic events can be classified into four groups initiated by different pathways.

  2. Toll-like Receptors of the Ascidian Ciona intestinalis

    PubMed Central

    Sasaki, Naoko; Ogasawara, Michio; Sekiguchi, Toshio; Kusumoto, Shoichi; Satake, Honoo

    2009-01-01

    Key transmembrane proteins in the innate immune system, Toll-like receptors (TLRs), have been suggested to occur in the genome of non-mammalian organisms including invertebrates. However, authentic invertebrate TLRs have been neither structurally nor functionally investigated. In this paper, we originally present the structures, localization, ligand recognition, activities, and inflammatory cytokine production of all TLRs of the ascidian Ciona intestinalis, designated as Ci-TLR1 and Ci-TLR2. The amino acid sequence of Ci-TLR1 and Ci-TLR2 were found to possess unique structural organization with moderate sequence similarity to functionally characterized vertebrate TLRs. ci-tlr1 and ci-tlr2 genes were expressed predominantly in the stomach and intestine as well as in hemocytes. Ci-TLR1 and Ci-TLR2 expressed in HEK293 cells, unlike vertebrate TLRs, were localized to both the plasma membrane and endosomes. Intriguingly, both Ci-TLR1 and Ci-TLR2 stimulate NF-κB induction in response to multiple pathogenic ligands such as double-stranded RNA, and bacterial cell wall components that are differentially recognized by respective vertebrate TLRs, revealing that Ci-TLRs recognize broader pathogen-associated molecular patterns than vertebrate TLRs. The Ci-TLR-stimulating pathogenic ligands also induced the expression of Ci-TNFα in the intestine and stomach where Ci-TLRs are expressed. These results provide evidence that the TLR-triggered innate immune systems are essentially conserved in ascidians, and that Ci-TLRs possess “hybrid” biological and immunological functions, compared with vertebrate TLRs. Moreover, it is presumed that chordate TLR ancestors also acquired the Ci-TLR-like multiple cellular localization and pathogen-associated molecular pattern recognition. PMID:19651780

  3. Construction of a cDNA microarray derived from the ascidian Ciona intestinalis.

    PubMed

    Azumi, Kaoru; Takahashi, Hiroki; Miki, Yasufumi; Fujie, Manabu; Usami, Takeshi; Ishikawa, Hisayoshi; Kitayama, Atsusi; Satou, Yutaka; Ueno, Naoto; Satoh, Nori

    2003-10-01

    A cDNA microarray was constructed from a basal chordate, the ascidian Ciona intestinalis. The draft genome of Ciona has been read and inferred to contain approximately 16,000 protein-coding genes, and cDNAs for transcripts of 13,464 genes have been characterized and compiled as the "Ciona intestinalis Gene Collection Release I". In the present study, we constructed a cDNA microarray of these 13,464 Ciona genes. A preliminary experiment with Cy3- and Cy5-labeled probes showed extensive differential gene expression between fertilized eggs and larvae. In addition, there was a good correlation between results obtained by the present microarray analysis and those from previous EST analyses. This first microarray of a large collection of Ciona intestinalis cDNA clones should facilitate the analysis of global gene expression and gene networks during the embryogenesis of basal chordates.

  4. Huntingtin gene evolution in Chordata and its peculiar features in the ascidian Ciona genus

    PubMed Central

    Gissi, Carmela; Pesole, Graziano; Cattaneo, Elena; Tartari, Marzia

    2006-01-01

    Background To gain insight into the evolutionary features of the huntingtin (htt) gene in Chordata, we have sequenced and characterized the full-length htt mRNA in the ascidian Ciona intestinalis, a basal chordate emerging as new invertebrate model organism. Moreover, taking advantage of the availability of genomic and EST sequences, the htt gene structure of a number of chordate species, including the cogeneric ascidian Ciona savignyi, and the vertebrates Xenopus and Gallus was reconstructed. Results The C. intestinalis htt transcript exhibits some peculiar features, such as spliced leader trans-splicing in the 98 nt-long 5' untranslated region (UTR), an alternative splicing in the coding region, eight alternative polyadenylation sites, and no similarities of both 5' and 3'UTRs compared to homologs of the cogeneric C. savignyi. The predicted protein is 2946 amino acids long, shorter than its vertebrate homologs, and lacks the polyQ and the polyP stretches found in the the N-terminal regions of mammalian homologs. The exon-intron organization of the htt gene is almost identical among vertebrates, and significantly conserved between Ciona and vertebrates, allowing us to hypothesize an ancestral chordate gene consisting of at least 40 coding exons. Conclusion During chordate diversification, events of gain/loss, sliding, phase changes, and expansion of introns occurred in both vertebrate and ascidian lineages predominantly in the 5'-half of the htt gene, where there is also evidence of lineage-specific evolutionary dynamics in vertebrates. On the contrary, the 3'-half of the gene is highly conserved in all chordates at the level of both gene structure and protein sequence. Between the two Ciona species, a fast evolutionary rate and/or an early divergence time is suggested by the absence of significant similarity between UTRs, protein divergence comparable to that observed between mammals and fishes, and different distribution of repetitive elements. PMID:17092333

  5. Time course for tail regression during metamorphosis of the ascidian Ciona intestinalis.

    PubMed

    Matsunobu, Shohei; Sasakura, Yasunori

    2015-09-01

    In most ascidians, the tadpole-like swimming larvae dramatically change their body-plans during metamorphosis and develop into sessile adults. The mechanisms of ascidian metamorphosis have been researched and debated for many years. Until now information on the detailed time course of the initiation and completion of each metamorphic event has not been described. One dramatic and important event in ascidian metamorphosis is tail regression, in which ascidian larvae lose their tails to adjust themselves to sessile life. In the present study, we measured the time associated with tail regression in the ascidian Ciona intestinalis. Larvae are thought to acquire competency for each metamorphic event in certain developmental periods. We show that the timing with which the competence for tail regression is acquired is determined by the time since hatching, and this timing is not affected by the timing of post-hatching events such as adhesion. Because larvae need to adhere to substrates with their papillae to induce tail regression, we measured the duration for which larvae need to remain adhered in order to initiate tail regression and the time needed for the tail to regress. Larvae acquire the ability to adhere to substrates before they acquire tail regression competence. We found that when larvae adhered before they acquired tail regression competence, they were able to remember the experience of adhesion until they acquired the ability to undergo tail regression. The time course of the events associated with tail regression provides a valuable reference, upon which the cellular and molecular mechanisms of ascidian metamorphosis can be elucidated.

  6. Siphon regeneration capacity is compromised during aging in the ascidian Ciona intestinalis.

    PubMed

    Jeffery, William R

    2012-01-01

    The ascidian Ciona intestinalis has a short life span and powerful regeneration capacities. The regeneration of the oral siphon (OS) involves wound healing, blastema formation, cell proliferation, and replacement of 8 oral pigment organs (OPO), the latter via differentiation and migration of stem/precursor cells from localized niches in the siphon. The restoration of OPO pattern during OS regeneration occurs with a high degree of accuracy through three successive cycles of amputation. It is shown here that oral siphons of the largest and oldest members of a wild Ciona population do not completely regenerate their siphons after amputation. The loss of regeneration capacity was accompanied by reduced cell proliferation. In contrast to arrested OS outgrowth, the stem/precursor cells responsible for OPO replacement "over-differentiate" after OS amputation in the oldest animals, the typical number of OPO is increased from 8 to 12-16, and malformed OPO are produced. Also in contrast to younger animals, the oldest animals of the population show arrested OPO development after two consecutive cycles of amputation and regeneration. We conclude that there is a size and age threshold in Ciona after which the regenerative capacity of the OS is compromised due to effects of aging on cell proliferation.

  7. Spermiotoxicity of nickel nanoparticles in the marine invertebrate Ciona intestinalis (ascidians).

    PubMed

    Gallo, Alessandra; Boni, Raffaele; Buttino, Isabella; Tosti, Elisabetta

    2016-10-01

    Nickel nanoparticles (Ni NPs) are increasingly used in modern industries as catalysts, sensors, and in electronic applications. Due to this large use, their inputs into marine environment have significantly increased; however, the potential ecotoxicological effects in marine environment have so far received little attention. In particular, little is known on the impact of NPs on gamete quality of marine organisms and on the consequences on fertility potential. The present study examines, for the first time, the impact of Ni NPs exposure on sperm quality of the marine invertebrate Ciona intestinalis (ascidian). Several parameters related with sperm status such as plasma membrane lipid peroxidation, mitochondrial membrane potential (MMP), intracellular pH, DNA integrity, and fertilizing ability were assessed as toxicity end points after exposure to different Ni NPs concentrations. Ni NPs generate oxidative stress that in turn induces lipid peroxidation and DNA fragmentation, and alters MMP and sperm morphology. Furthermore, sperm exposure to Ni NPs affects their fertilizing ability and causes developmental anomalies in the offspring. All together, these results reveal a spermiotoxicity of Ni NPs in ascidians suggesting that the application of these NPs should be carefully assessed as to their potential toxic effects on the health of marine organisms that, in turn, may influence the ecological system. This study shows that ascidian sperm represent a suitable and sensitive tool for the investigation of the toxicity of NPs entered into marine environment, for defining the mechanisms of toxic action and for the environmental monitoring purpose.

  8. Spermiotoxicity of nickel nanoparticles in the marine invertebrate Ciona intestinalis (ascidians)

    PubMed Central

    Gallo, Alessandra; Boni, Raffaele; Buttino, Isabella; Tosti, Elisabetta

    2016-01-01

    Abstract Nickel nanoparticles (Ni NPs) are increasingly used in modern industries as catalysts, sensors, and in electronic applications. Due to this large use, their inputs into marine environment have significantly increased; however, the potential ecotoxicological effects in marine environment have so far received little attention. In particular, little is known on the impact of NPs on gamete quality of marine organisms and on the consequences on fertility potential. The present study examines, for the first time, the impact of Ni NPs exposure on sperm quality of the marine invertebrate Ciona intestinalis (ascidian). Several parameters related with sperm status such as plasma membrane lipid peroxidation, mitochondrial membrane potential (MMP), intracellular pH, DNA integrity, and fertilizing ability were assessed as toxicity end points after exposure to different Ni NPs concentrations. Ni NPs generate oxidative stress that in turn induces lipid peroxidation and DNA fragmentation, and alters MMP and sperm morphology. Furthermore, sperm exposure to Ni NPs affects their fertilizing ability and causes developmental anomalies in the offspring. All together, these results reveal a spermiotoxicity of Ni NPs in ascidians suggesting that the application of these NPs should be carefully assessed as to their potential toxic effects on the health of marine organisms that, in turn, may influence the ecological system. This study shows that ascidian sperm represent a suitable and sensitive tool for the investigation of the toxicity of NPs entered into marine environment, for defining the mechanisms of toxic action and for the environmental monitoring purpose. PMID:27080039

  9. Spermiotoxicity of nickel nanoparticles in the marine invertebrate Ciona intestinalis (ascidians).

    PubMed

    Gallo, Alessandra; Boni, Raffaele; Buttino, Isabella; Tosti, Elisabetta

    2016-10-01

    Nickel nanoparticles (Ni NPs) are increasingly used in modern industries as catalysts, sensors, and in electronic applications. Due to this large use, their inputs into marine environment have significantly increased; however, the potential ecotoxicological effects in marine environment have so far received little attention. In particular, little is known on the impact of NPs on gamete quality of marine organisms and on the consequences on fertility potential. The present study examines, for the first time, the impact of Ni NPs exposure on sperm quality of the marine invertebrate Ciona intestinalis (ascidian). Several parameters related with sperm status such as plasma membrane lipid peroxidation, mitochondrial membrane potential (MMP), intracellular pH, DNA integrity, and fertilizing ability were assessed as toxicity end points after exposure to different Ni NPs concentrations. Ni NPs generate oxidative stress that in turn induces lipid peroxidation and DNA fragmentation, and alters MMP and sperm morphology. Furthermore, sperm exposure to Ni NPs affects their fertilizing ability and causes developmental anomalies in the offspring. All together, these results reveal a spermiotoxicity of Ni NPs in ascidians suggesting that the application of these NPs should be carefully assessed as to their potential toxic effects on the health of marine organisms that, in turn, may influence the ecological system. This study shows that ascidian sperm represent a suitable and sensitive tool for the investigation of the toxicity of NPs entered into marine environment, for defining the mechanisms of toxic action and for the environmental monitoring purpose. PMID:27080039

  10. Regeneration of oral siphon pigment organs in the ascidian Ciona intestinalis.

    PubMed

    Auger, Hélène; Sasakura, Yasunori; Joly, Jean-Stéphane; Jeffery, William R

    2010-03-15

    Ascidians have powerful capacities for regeneration but the underlying mechanisms are poorly understood. Here we examine oral siphon regeneration in the solitary ascidian Ciona intestinalis. Following amputation, the oral siphon rapidly reforms oral pigment organs (OPO) at its distal margin prior to slower regeneration of proximal siphon parts. The early stages of oral siphon reformation include cell proliferation and re-growth of the siphon nerves, although the neural complex (adult brain and associated organs) is not required for regeneration. Young animals reform OPO more rapidly after amputation than old animals indicating that regeneration is age dependent. UV irradiation, microcautery, and cultured siphon explant experiments indicate that OPOs are replaced as independent units based on local differentiation of progenitor cells within the siphon, rather than by cell migration from a distant source in the body. The typical pattern of eight OPOs and siphon lobes is restored with fidelity after distal amputation of the oral siphon, but as many as 16 OPOs and lobes can be reformed following proximal amputation near the siphon base. Thus, the pattern of OPO regeneration is determined by cues positioned along the proximal distal axis of the oral siphon. A model is presented in which columns of siphon tissue along the proximal-distal axis below pre-existing OPO are responsible for reproducing the normal OPO pattern during regeneration. This study reveals previously unknown principles of oral siphon and OPO regeneration that will be important for developing Ciona as a regeneration model in urochordates, which may be the closest living relatives of vertebrates.

  11. Closing the wounds: one hundred and twenty five years of regenerative biology in the ascidian Ciona intestinalis.

    PubMed

    Jeffery, William R

    2015-01-01

    This year marks the 125th anniversary of the beginning of regeneration research in the ascidian Ciona intestinalis. A brief note was published in 1891, reporting the regeneration of the Ciona neural complex and siphons. This launched an active period of Ciona regeneration research culminating in the demonstration of partial body regeneration: the ability of proximal body parts to regenerate distal ones, but not vice versa. In a process resembling regeneration, wounds in the siphon tube were discovered to result in the formation of an ectopic siphon. Ciona regeneration research then lapsed into a period of relative inactivity after the purported demonstration of the inheritance of acquired characters using siphon regeneration as a model. Around the turn of the present century, Ciona regeneration research experienced a new blossoming. The current studies established the morphological and physiological integrity of the regeneration process and its resemblance to ontogeny. They also determined some of the cell types responsible for tissue and organ replacement and their sources in the body. Finally, they showed that regenerative capacity is reduced with age. Many other aspects of regeneration now can be studied at the mechanistic level because of the extensive molecular tools available in Ciona.

  12. A one-dimensional model of PCP signaling: polarized cell behavior in the notochord of the ascidian Ciona

    PubMed Central

    Kourakis, Matthew J.; Reeves, Wendy; Newman-Smith, Erin; Maury, Benoit; Abdul-Wajid, Sarah; Smith, William C.

    2014-01-01

    Despite its importance in development and physiology the planar cell polarity (PCP) pathway remains one of the most enigmatic signaling mechanisms. The notochord of the ascidian Ciona provides a unique model for investigating the PCP pathway. Interestingly, the notochord appears to be the only embryonic structure in Ciona activating the PCP pathway. Moreover, the Ciona notochord as a single-file array of forty polarized cells is a uniquely tractable system for the study of polarization dynamics and the transmission of the PCP pathway. Here, we test models for propagation of a polarizing signal, interrogating temporal, spatial and signaling requirements. A simple cell-cell relay cascading through the entire length of the notochord is not supported; instead a more complex mechanism is revealed, with interactions influencing polarity between neighboring cells, but not distant ones. Mechanisms coordinating notochord-wide polarity remain elusive, but appear to entrain general (i.e., global) polarity even while local interactions remain important. However, this global polarizer does not appear to act as a localized, spatially-restricted determinant. Coordination of polarity along the long axis of the notochord requires the PCP pathway, a role we demonstrate is temporally distinct from this pathway’s earlier role in convergent extension and intercalation. We also reveal polarity in the notochord to be dynamic: a cell’s polarity state can be changed and then restored, underscoring the Ciona notochord’s amenability for in vivo studies of PCP. PMID:25173874

  13. Metamorphosis of the invasive ascidian Ciona savignyi: environmental variables and chemical exposure.

    PubMed

    Cahill, Patrick L; Atalah, Javier; Selwood, Andrew I; Kuhajek, Jeanne M

    2016-01-01

    In this study, the effects of environmental variables on larval metamorphosis of the solitary ascidian Ciona savignyi were investigated in a laboratory setting. The progression of metamorphic changes were tracked under various temperature, photoperiod, substrate, larval density, and vessel size regimes. Metamorphosis was maximised at 18 °C, 12:12 h subdued light:dark, smooth polystyrene substrate, and 10 larvae mL(-1) in a twelve-well tissue culture plate. Eliminating the air-water interface by filling culture vessels to capacity further increased the proportion of metamorphosed larvae; 87 ± 5% of larvae completed metamorphosis within 5 days compared to 45 ± 5% in control wells. The effects of the reference antifouling compounds polygodial, portimine, oroidin, chlorothalonil, and tolylfluanid on C. savignyi were subsequently determined, highlighting (1) the sensitivity of C. savignyi metamorphosis to chemical exposure and (2) the potential to use C. savignyi larvae to screen for bioactivity in an optimised laboratory setting. The compounds were bioactive in the low ng mL(-1) to high µg mL(-1) range. Polygodial was chosen for additional investigations, where it was shown that mean reductions in the proportions of larvae reaching stage E were highly repeatable both within (repeatability = 14 ± 9%) and between (intermediate precision = 17 ± 3%) independent experiments. An environmental extract had no effect on the larvae but exposing larvae to both the extract and polygodial reduced potency relative to polygodial alone. This change in potency stresses the need for caution when working with complex samples, as is routinely implemented when isolating natural compounds from their biological source. Overall, the outcomes of this study highlight the sensitivity of C. savignyi metamorphosis to environmental variations and chemical exposure.

  14. Metamorphosis of the invasive ascidian Ciona savignyi: environmental variables and chemical exposure

    PubMed Central

    Atalah, Javier; Selwood, Andrew I.; Kuhajek, Jeanne M.

    2016-01-01

    In this study, the effects of environmental variables on larval metamorphosis of the solitary ascidian Ciona savignyi were investigated in a laboratory setting. The progression of metamorphic changes were tracked under various temperature, photoperiod, substrate, larval density, and vessel size regimes. Metamorphosis was maximised at 18 °C, 12:12 h subdued light:dark, smooth polystyrene substrate, and 10 larvae mL−1 in a twelve-well tissue culture plate. Eliminating the air-water interface by filling culture vessels to capacity further increased the proportion of metamorphosed larvae; 87 ± 5% of larvae completed metamorphosis within 5 days compared to 45 ± 5% in control wells. The effects of the reference antifouling compounds polygodial, portimine, oroidin, chlorothalonil, and tolylfluanid on C. savignyi were subsequently determined, highlighting (1) the sensitivity of C. savignyi metamorphosis to chemical exposure and (2) the potential to use C. savignyi larvae to screen for bioactivity in an optimised laboratory setting. The compounds were bioactive in the low ng mL−1 to high µg mL−1 range. Polygodial was chosen for additional investigations, where it was shown that mean reductions in the proportions of larvae reaching stage E were highly repeatable both within (repeatability = 14 ± 9%) and between (intermediate precision = 17 ± 3%) independent experiments. An environmental extract had no effect on the larvae but exposing larvae to both the extract and polygodial reduced potency relative to polygodial alone. This change in potency stresses the need for caution when working with complex samples, as is routinely implemented when isolating natural compounds from their biological source. Overall, the outcomes of this study highlight the sensitivity of C. savignyi metamorphosis to environmental variations and chemical exposure. PMID:26966668

  15. Ciona Genetics

    PubMed Central

    Veeman, Michael T.; Chiba, Shota; Smith, William C.

    2010-01-01

    Ascidians, such as Ciona, are invertebrate chordates with simple embryonic body plans and small, relatively non-redundant genomes. Ciona genetics is in its infancy compared to many other model systems, but it provides a powerful method for studying this important vertebrate outgroup. Here we give basic methods for genetic analysis of Ciona, including protocols for controlled crosses both by natural spawning and by the surgical isolation of gametes; the identification and propagation of mutant lines; and strategies for positional cloning. PMID:21805273

  16. Distal regeneration involves the age dependent activity of branchial sac stem cells in the ascidian Ciona intestinalis

    PubMed Central

    2014-01-01

    Abstract Tunicates have high capacities for regeneration but the underlying mechanisms and their relationship to life cycle progression are not well understood. Here we investigate the regeneration of distal structures in the ascidian tunicate Ciona intestinalis. Analysis of regenerative potential along the proximal−distal body axis indicated that distal organs, such as the siphons, their pigmented sensory organs, and the neural complex, could only be replaced from body fragments containing the branchial sac. Distal regeneration involves the formation of a blastema composed of cells that undergo cell proliferation prior to differentiation and cells that differentiate without cell proliferation. Both cell types originate in the branchial sac and appear in the blastema at different times after distal injury. Whereas the branchial sac stem cells are present in young animals, they are depleted in old animals that have lost their regeneration capacity. Thus Ciona adults contain a population of age‐related stem cells located in the branchial sac that are a source of precursors for distal body regeneration. PMID:25893097

  17. Toxicity assessment of the antifouling compound zinc pyrithione using early developmental stages of the ascidian Ciona intestinalis.

    PubMed

    Bellas, Juan

    2005-01-01

    This study investigated the toxicity of zinc pyrithione (Zpt) on the early stages of development of the ascidian Ciona intestinalis. Larval morphological abnormalities were studied after the exposure of C. intestinalis embryos at different stages of development. The median effective concentrations (EC50) ranged from 226-590 nM. The larval settlement stage was the most sensitive to Zpt. Toxic effects of Zpt on larval settlement were detected at 9 nM (EC10). The inhibition of C. intestinalis embryonic development was also used to study the loss of toxicity in Zpt solutions exposed to direct sunlight and laboratory UV light. The results showed that the toxicity of Zpt solutions decreased but did not disappear after 4 h exposure to direct sunlight (EC50 = 484 nM) or UV light (EC50 = 453 nM), compared to control Zpt solutions prepared in dark conditions. On the basis of the present data, predicted no effect concentrations of Zpt to C. intestinalis larvae are lower than predicted environmental concentrations of Zpt in certain polluted areas and therefore, may pose a risk to C. intestinalis populations. PMID:16522542

  18. Complete mtDNA of Ciona intestinalis reveals extensive gene rearrangement and the presence of an atp8 and an extra trnM gene in ascidians.

    PubMed

    Gissi, Carmela; Iannelli, Fabio; Pesole, Graziano

    2004-04-01

    The complete mitochondrial genome (mtDNA) of the model organism Ciona intestinalis (Urochordata, Ascidiacea) has been amplified by long-PCR using specific primers designed on putative mitochondrial transcripts identified from publicly available mitochondrial-like expressed sequence tags. The C. intestinalis mtDNA encodes 39 genes: 2 rRNAs, 13 subunits of the respiratory complexes, including ATPase subunit 8 ( atp8), and 24 tRNAs, including 2 tRNA-Met with anticodons 5'-UAU-3'and 5'-CAU-3', respectively. All genes are transcribed from the same strand. This gene content seems to be a common feature of ascidian mtDNAs, as we have verified the presence of a previously undetected atp8 and of two trnM genes in the two other sequenced ascidian mtDNAs. Extensive gene rearrangement has been found in C. intestinalis with respect not only to the common Vertebrata/Cephalochordata/Hemichordata gene organization but also to other ascidian mtDNAs, including the cogeneric Ciona savignyi. Other features such as the absence of long noncoding regions, the shortness of rRNA genes, the low GC content (21.4%), and the absence of asymmetric base distribution between the two strands suggest that this genome is more similar to those of some protostomes than to deuterostomes. PMID:15114417

  19. Complete mtDNA of Ciona intestinalis reveals extensive gene rearrangement and the presence of an atp8 and an extra trnM gene in ascidians.

    PubMed

    Gissi, Carmela; Iannelli, Fabio; Pesole, Graziano

    2004-04-01

    The complete mitochondrial genome (mtDNA) of the model organism Ciona intestinalis (Urochordata, Ascidiacea) has been amplified by long-PCR using specific primers designed on putative mitochondrial transcripts identified from publicly available mitochondrial-like expressed sequence tags. The C. intestinalis mtDNA encodes 39 genes: 2 rRNAs, 13 subunits of the respiratory complexes, including ATPase subunit 8 ( atp8), and 24 tRNAs, including 2 tRNA-Met with anticodons 5'-UAU-3'and 5'-CAU-3', respectively. All genes are transcribed from the same strand. This gene content seems to be a common feature of ascidian mtDNAs, as we have verified the presence of a previously undetected atp8 and of two trnM genes in the two other sequenced ascidian mtDNAs. Extensive gene rearrangement has been found in C. intestinalis with respect not only to the common Vertebrata/Cephalochordata/Hemichordata gene organization but also to other ascidian mtDNAs, including the cogeneric Ciona savignyi. Other features such as the absence of long noncoding regions, the shortness of rRNA genes, the low GC content (21.4%), and the absence of asymmetric base distribution between the two strands suggest that this genome is more similar to those of some protostomes than to deuterostomes.

  20. Genomewide gene-associated microsatellite markers for the model invasive ascidian, Ciona intestinalis species complex.

    PubMed

    Lin, Yaping; Chen, Yiyong; Xiong, Wei; Zhan, Aibin

    2016-05-01

    The vase tunicate, Ciona intestinalis species complex, has become a good model for ecological and evolutionary studies, especially those focusing on microevolution associated with rapidly changing environments. However, genomewide genetic markers are still lacking. Here, we characterized a large set of genomewide gene-associated microsatellite markers for C. intestinalis spA (=C. robusta). Bioinformatic analysis identified 4654 microsatellites from expressed sequence tags (ESTs), 2126 of which successfully assigned to chromosomes were selected for further analysis. Based on the distribution evenness on chromosomes, function annotation and suitability for primer design, we chose 545 candidate microsatellites for further characterization. After amplification validation and variation assessment, 218 loci were polymorphic in at least one of the two populations collected from the coast of Arenys de Mar, Spain (N = 24-48), and Cape Town, South Africa (N = 24-33). The number of alleles, observed heterozygosity and expected heterozygosity ranged from 2 to 11, 0 to 0.833 and 0.021 to 0.818, and from 2 to 10, 0 to 0.879 and 0.031 to 0.845 for the Spanish and African populations, respectively. When all microsatellites were tested for cross-species utility, only 60 loci (25.8%) could be successfully amplified and all loci were polymorphic in C. intestinalis spB. A high level of genomewide polymorphism is likely responsible for the low transferability. The large set of microsatellite markers characterized here is expected to provide a useful genomewide resource for ecological and evolutionary studies using C. intestinalis as a model. PMID:26505988

  1. Nitric Oxide Affects ERK Signaling through Down-Regulation of MAP Kinase Phosphatase Levels during Larval Development of the Ascidian Ciona intestinalis

    PubMed Central

    Palumbo, Anna

    2014-01-01

    In the ascidian Ciona intestinalis larval development and metamorphosis require a complex interplay of events, including nitric oxide (NO) production, MAP kinases (ERK, JNK) and caspase-3 activation. We have previously shown that NO levels affect the rate of metamorphosis, regulate caspase activity and promote an oxidative stress pathway, resulting in protein nitration. Here, we report that NO down-regulates MAP kinase phosphatases (mkps) expression affecting positively ERK signaling. By pharmacological approach, we observed that the reduction of endogenous NO levels caused a decrease of ERK phosphorylation, whereas increasing levels of NO induced ERK activation. We have also identified the ERK gene network affected by NO, including mpk1, mpk3 and some key developmental genes by quantitative gene expression analysis. We demonstrate that NO induces an ERK-independent down-regulation of mkp1 and mkp3, responsible for maintaining the ERK phosphorylation levels necessary for transcription of key metamorphic genes, such as the hormone receptor rev-erb and the van willebrand protein vwa1c. These results add new insights into the role played by NO during larval development and metamorphosis in Ciona, highlighting the cross-talk between different signaling pathways. PMID:25058405

  2. The diatom-derived aldehyde decadienal affects life cycle transition in the ascidian Ciona intestinalis through nitric oxide/ERK signalling

    PubMed Central

    Castellano, Immacolata; Ercolesi, Elena; Romano, Giovanna; Ianora, Adrianna; Palumbo, Anna

    2015-01-01

    Polyunsaturated aldehydes (PUAs) are fatty-acid-derived metabolites produced by some microalgae, including different diatom species. PUAs are mainly produced as a wound-activated defence mechanism against microalgal predators or released from senescent cells at the end of a bloom. PUAs, including 2,4-trans-decadienal (DD), induce deleterious effects on embryonic and larval development of several planktonic and benthic organisms. Here, we report on the effects of DD on larval development and metamorphosis of the ascidian Ciona intestinalis. Ciona larval development is regulated by the cross-talking of different molecular events, including nitric oxide (NO) production, ERK activation and caspase 3-dependent apoptosis. We report that treatment with DD at the competence larval stage results in a delay in metamorphosis. DD affects redox balance by reducing total glutathione and NO levels. By biochemical and quantitative gene expression analysis, we identify the NO-signalling network affected by DD, including the upregulation of ERK phosphatase mkp1 and consequent reduction of ERK phosphorylation, with final changes in the expression of downstream ERK target genes. Overall, these results give new insights into the molecular pathways induced in marine organisms after exposure to PUAs during larval development, demonstrating that this aldehyde affects key checkpoints of larval transition from the vegetative to the reproductive life stage. PMID:25788553

  3. A pipeline for the systematic identification of non-redundant full-ORF cDNAs for polymorphic and evolutionary divergent genomes: Application to the ascidian Ciona intestinalis

    PubMed Central

    Gilchrist, Michael J.; Sobral, Daniel; Khoueiry, Pierre; Daian, Fabrice; Laporte, Batiste; Patrushev, Ilya; Matsumoto, Jun; Dewar, Ken; Hastings, Kenneth E.M.; Satou, Yutaka; Lemaire, Patrick; Rothbächer, Ute

    2015-01-01

    Genome-wide resources, such as collections of cDNA clones encoding for complete proteins (full-ORF clones), are crucial tools for studying the evolution of gene function and genetic interactions. Non-model organisms, in particular marine organisms, provide a rich source of functional diversity. Marine organism genomes are, however, frequently highly polymorphic and encode proteins that diverge significantly from those of well-annotated model genomes. The construction of full-ORF clone collections from non-model organisms is hindered by the difficulty of predicting accurately the N-terminal ends of proteins, and distinguishing recent paralogs from highly polymorphic alleles. We report a computational strategy that overcomes these difficulties, and allows for accurate gene level clustering of transcript data followed by the automated identification of full-ORFs with correct 5′- and 3′-ends. It is robust to polymorphism, includes paralog calling and does not require evolutionary proximity to well annotated model organisms. We developed this pipeline for the ascidian Ciona intestinalis, a highly polymorphic member of the divergent sister group of the vertebrates, emerging as a powerful model organism to study chordate gene function, Gene Regulatory Networks and molecular mechanisms underlying human pathologies. Using this pipeline we have generated the first full-ORF collection for a highly polymorphic marine invertebrate. It contains 19,163 full-ORF cDNA clones covering 60% of Ciona coding genes, and full-ORF orthologs for approximately half of curated human disease-associated genes. PMID:26025923

  4. Evolution of the chordate regeneration blastema: Differential gene expression and conserved role of notch signaling during siphon regeneration in the ascidian Ciona.

    PubMed

    Hamada, Mayuko; Goricki, Spela; Byerly, Mardi S; Satoh, Noriyuki; Jeffery, William R

    2015-09-15

    The regeneration of the oral siphon (OS) and other distal structures in the ascidian Ciona intestinalis occurs by epimorphosis involving the formation of a blastema of proliferating cells. Despite the longstanding use of Ciona as a model in molecular developmental biology, regeneration in this system has not been previously explored by molecular analysis. Here we have employed microarray analysis and quantitative real time RT-PCR to identify genes with differential expression profiles during OS regeneration. The majority of differentially expressed genes were downregulated during OS regeneration, suggesting roles in normal growth and homeostasis. However, a subset of differentially expressed genes was upregulated in the regenerating OS, suggesting functional roles during regeneration. Among the upregulated genes were key members of the Notch signaling pathway, including those encoding the delta and jagged ligands, two fringe modulators, and to a lesser extent the notch receptor. In situ hybridization showed a complementary pattern of delta1 and notch gene expression in the blastema of the regenerating OS. Chemical inhibition of the Notch signaling pathway reduced the levels of cell proliferation in the branchial sac, a stem cell niche that contributes progenitor cells to the regenerating OS, and in the OS regeneration blastema, where siphon muscle fibers eventually re-differentiate. Chemical inhibition also prevented the replacement of oral siphon pigment organs, sensory receptors rimming the entrance of the OS, and siphon muscle fibers, but had no effects on the formation of the wound epidermis. Since Notch signaling is involved in the maintenance of proliferative activity in both the Ciona and vertebrate regeneration blastema, the results suggest a conserved evolutionary role of this signaling pathway in chordate regeneration. The genes identified in this investigation provide the foundation for future molecular analysis of OS regeneration.

  5. Ci-Rga, a gene encoding an MtN3/saliva family transmembrane protein, is essential for tissue differentiation during embryogenesis of the ascidian Ciona intestinalis.

    PubMed

    Hamada, Mayuko; Wada, Shuichi; Kobayashi, Kenji; Satoh, Nori

    2005-09-01

    A novel gene (Ci-Rga) essential for tissue differentiation during embryogenesis of the ascidian Ciona intestinalis is reported here. This gene was identified through functional screening of Ciona genes required for development by translational inhibition experiments with morpholino antisense oligonucleotides. The deduced protein of Ci-Rga contains two copies of a domain with unknown function called the MtN3/saliva domain. Phylogenetic analysis showed that Ci-Rga belongs to the MtN3/saliva family of genes conserved among metazoans and plants, and is an ortholog of mouse Rga (Recombination-activating gene 1 gene activation). During Ciona embryogenesis, both maternal and zygotic transcripts of Ci-Rga were expressed. Translational inhibition of Ci-Rga with specific morpholino resulted in abnormal embryos in which the cleavage pattern became atypical and expression of marker genes for each of the six major tissues, namely the endoderm, muscle, mesenchyme, notochord, neural tissue, and epidermis, was lost or suppressed at the tailbud stage. Although differentiation of all the six major tissues was affected by Ci-Rga knock-down, the degree of abnormalities and the timing of appearance of abnormalities were different among tissues. Expression analysis of developmentally important genes involved in the fate specification, such as Ci-Bra, Ci-Twist-like1a, Ci-Otx, Ci-Fgf9/16/20, Ci-Lhx3, Ci-FoxD, and Ci-Tbx6b, showed that an initial step of the fate specification of notochord, mesenchyme, and neural tissue, but not of endoderm or muscle, is impaired in the knock-down embryo. These results showed that Ci-Rga is a multifunctional gene essential for tissue differentiation during embryogenesis, and is primarily required for the fate specification of notochord, mesenchyme, and neural tissue, and provide some insights into the function of this little-known group of genes.

  6. Evolution of the chordate regeneration blastema: Differential gene expression and conserved role of notch signaling during siphon regeneration in the ascidian Ciona.

    PubMed

    Hamada, Mayuko; Goricki, Spela; Byerly, Mardi S; Satoh, Noriyuki; Jeffery, William R

    2015-09-15

    The regeneration of the oral siphon (OS) and other distal structures in the ascidian Ciona intestinalis occurs by epimorphosis involving the formation of a blastema of proliferating cells. Despite the longstanding use of Ciona as a model in molecular developmental biology, regeneration in this system has not been previously explored by molecular analysis. Here we have employed microarray analysis and quantitative real time RT-PCR to identify genes with differential expression profiles during OS regeneration. The majority of differentially expressed genes were downregulated during OS regeneration, suggesting roles in normal growth and homeostasis. However, a subset of differentially expressed genes was upregulated in the regenerating OS, suggesting functional roles during regeneration. Among the upregulated genes were key members of the Notch signaling pathway, including those encoding the delta and jagged ligands, two fringe modulators, and to a lesser extent the notch receptor. In situ hybridization showed a complementary pattern of delta1 and notch gene expression in the blastema of the regenerating OS. Chemical inhibition of the Notch signaling pathway reduced the levels of cell proliferation in the branchial sac, a stem cell niche that contributes progenitor cells to the regenerating OS, and in the OS regeneration blastema, where siphon muscle fibers eventually re-differentiate. Chemical inhibition also prevented the replacement of oral siphon pigment organs, sensory receptors rimming the entrance of the OS, and siphon muscle fibers, but had no effects on the formation of the wound epidermis. Since Notch signaling is involved in the maintenance of proliferative activity in both the Ciona and vertebrate regeneration blastema, the results suggest a conserved evolutionary role of this signaling pathway in chordate regeneration. The genes identified in this investigation provide the foundation for future molecular analysis of OS regeneration. PMID:26206613

  7. Effects of the azole fungicide Imazalil on the development of the ascidian Ciona intestinalis (Chordata, Tunicata): morphological and molecular characterization of the induced phenotype.

    PubMed

    Zega, Giuliana; De Bernardi, Fiorenza; Groppelli, Silvia; Pennati, Roberta

    2009-02-19

    Imazalil (IMA) is a fungicide that is used extensively in fruit plantations and post-harvest treatments, but has teratogenic effects on vertebrate development, possibly due to the perturbation of retinoic acid (RA) levels in the embryo. Ascidians are sessile marine invertebrate chordates that develop through a tadpole larva, with a body plan that shares basic homologies with vertebrates. In this work, we tested the effects of IMA on the development of the solitary ascidian Ciona intestinalis by treating two-cell stage embryos with a range of concentrations (0.1, 0.5, 1, 2.5, 5, 10, 20 and 50microThe fungicide significantly altered ascidian development even at low concentrations and its effects were dose-dependent. Probit analysis revealed that the median lethal concentration, LC(50), was 4.87microM and the median teratogenic concentration, TC(50), was 0.73microM. Larvae developing from embryos exposed to IMA showed malformations of the anterior structures, which became more severe as IMA concentration increased. In particular, the anterior nervous system and the sensory vesicle were reduced, and the pigmented organs (the ocellus and the otolith) progressively lost their pigmentation. The larval phenotype induced by 5microM IMA exposure was further characterized by means of molecular analysis, through whole mount in situ hybridization with probes for genes related to the nervous system: Ci-Otp, Ci-GAD, Ci-POU IV, which are markers of the anterior neuro-ectoderm, the central nervous system and the peripheral nervous system respectively, and Ci-Hox-1, a gene specifically activated by RA, and Ci-Aldh2, a gene for aldehyde dehydrogenase, which is involved in RA synthesis. The altered expression of Ci-Otp, Ci-GAD, Ci-POU IV in 5microM IMA-exposed larvae compared to control larvae showed that this fungicide could affect the differentiation of the anterior nervous system, particularly of the sensory vesicle neurons. Recent studies suggest a similarity between IMA- and RA

  8. The Mediterranean non-indigenous ascidian Polyandrocarpa zorritensis: Microbiological accumulation capability and environmental implications.

    PubMed

    Stabili, Loredana; Licciano, Margherita; Longo, Caterina; Lezzi, Marco; Giangrande, Adriana

    2015-12-15

    We investigated the bacterial accumulation and digestion capability of Polyandrocarpa zorritensis, a non-indigenous colonial ascidian originally described in Peru and later found in the Mediterranean. Microbiological analyses were carried out on homogenates from "unstarved" and "starved" ascidians and seawater from the same sampling site (Adriatic Sea, Italy). Culturable heterotrophic bacteria (22 °C), total culturable bacteria (37 °C) and vibrios abundances were determined on Marine Agar 2216, Plate Count Agar and TCBS Agar, respectively. Microbial pollution indicators were measured by the most probable number method. All the examined microbiological groups were accumulated by ascidians but differently digested. An interesting outcome is the capability of P. zorritensis to digest allochthonous microorganisms such as coliforms as well as culturable bacteria at 37 °C, counteracting the effects of microbial pollution. Thus, the potential exploitation of these filter feeders to restore polluted seawater should be taken into consideration in the management of this alien species. PMID:26561443

  9. Reference gene selection for quantitative gene expression studies during biological invasions: A test on multiple genes and tissues in a model ascidian Ciona savignyi.

    PubMed

    Huang, Xuena; Gao, Yangchun; Jiang, Bei; Zhou, Zunchun; Zhan, Aibin

    2016-01-15

    As invasive species have successfully colonized a wide range of dramatically different local environments, they offer a good opportunity to study interactions between species and rapidly changing environments. Gene expression represents one of the primary and crucial mechanisms for rapid adaptation to local environments. Here, we aim to select reference genes for quantitative gene expression analysis based on quantitative Real-Time PCR (qRT-PCR) for a model invasive ascidian, Ciona savignyi. We analyzed the stability of ten candidate reference genes in three tissues (siphon, pharynx and intestine) under two key environmental stresses (temperature and salinity) in the marine realm based on three programs (geNorm, NormFinder and delta Ct method). Our results demonstrated only minor difference for stability rankings among the three methods. The use of different single reference gene might influence the data interpretation, while multiple reference genes could minimize possible errors. Therefore, reference gene combinations were recommended for different tissues - the optimal reference gene combination for siphon was RPS15 and RPL17 under temperature stress, and RPL17, UBQ and TubA under salinity treatment; for pharynx, TubB, TubA and RPL17 were the most stable genes under temperature stress, while TubB, TubA and UBQ were the best under salinity stress; for intestine, UBQ, RPS15 and RPL17 were the most reliable reference genes under both treatments. Our results suggest that the necessity of selection and test of reference genes for different tissues under varying environmental stresses. The results obtained here are expected to reveal mechanisms of gene expression-mediated invasion success using C. savignyi as a model species. PMID:26428313

  10. Reference gene selection for quantitative gene expression studies during biological invasions: A test on multiple genes and tissues in a model ascidian Ciona savignyi.

    PubMed

    Huang, Xuena; Gao, Yangchun; Jiang, Bei; Zhou, Zunchun; Zhan, Aibin

    2016-01-15

    As invasive species have successfully colonized a wide range of dramatically different local environments, they offer a good opportunity to study interactions between species and rapidly changing environments. Gene expression represents one of the primary and crucial mechanisms for rapid adaptation to local environments. Here, we aim to select reference genes for quantitative gene expression analysis based on quantitative Real-Time PCR (qRT-PCR) for a model invasive ascidian, Ciona savignyi. We analyzed the stability of ten candidate reference genes in three tissues (siphon, pharynx and intestine) under two key environmental stresses (temperature and salinity) in the marine realm based on three programs (geNorm, NormFinder and delta Ct method). Our results demonstrated only minor difference for stability rankings among the three methods. The use of different single reference gene might influence the data interpretation, while multiple reference genes could minimize possible errors. Therefore, reference gene combinations were recommended for different tissues - the optimal reference gene combination for siphon was RPS15 and RPL17 under temperature stress, and RPL17, UBQ and TubA under salinity treatment; for pharynx, TubB, TubA and RPL17 were the most stable genes under temperature stress, while TubB, TubA and UBQ were the best under salinity stress; for intestine, UBQ, RPS15 and RPL17 were the most reliable reference genes under both treatments. Our results suggest that the necessity of selection and test of reference genes for different tissues under varying environmental stresses. The results obtained here are expected to reveal mechanisms of gene expression-mediated invasion success using C. savignyi as a model species.

  11. Structure and Configuration of Phosphoeleganin, a Protein Tyrosine Phosphatase 1B Inhibitor from the Mediterranean Ascidian Sidnyum elegans.

    PubMed

    Imperatore, Concetta; Luciano, Paolo; Aiello, Anna; Vitalone, Rocco; Irace, Carlo; Santamaria, Rita; Li, Jia; Guo, Yue-W; Menna, Marialuisa

    2016-04-22

    A new phosphorylated polyketide, phosphoeleganin (1), has been isolated from the Mediterranean ascidian Sidnyum elegans. Its structure and configuration have been determined by extensive use of 2D NMR and microscale chemical degradation and/or derivatization. Phosphoeleganin (1) inhibited the protein tyrosine phosphatase 1B (PTP1B) activity. PMID:27064611

  12. Ascidian bioresources: common and variant chemical compositions and exploitation strategy - examples of Halocynthia roretzi, Styela plicata, Ascidia sp. and Ciona intestinalis.

    PubMed

    Zhao, Yadong; Li, Jiebing

    2016-01-01

    To explore abundant marine ascidian bioresources, four species from two orders have been compared in their chemical compositions. After a universal separation of the animal body into two fractions, all tunics have been found rich in carbohydrate contents, while all inner body tissues are richer in proteins. Cellulose is present almost exclusively in the tunics and more in the order Stolidobranchia, while more sulfated polysaccharides are present in Phlebobranchia species. Almost all proteins are collagens with a high essential amino acid index and high delicious amino acid (DAA) content. All fractions also have high contents of good-quality fatty acids and trace minerals but low toxic element contents, with different sterols and glycosaminoglycans. There are species-specific characteristics observed for vanadium accumulation and sterol structures which are also meaningful for ascidian chemotaxonomy and resource exploitation. It is suggested that in addition to the present utilizations of tunics for cellulose production and of some species' inner body tissues as human food, one should explore all species' inner body tissues as human foods and all tunics as food or animal feed with the contained cellulose as dietary fiber. Collagens, sulfated polysaccharides, glycosaminoglycans, sterols and trace elements could be explored as byproducts for, e.g. pharmaceutical and chemical industries. PMID:27049617

  13. Application of the cis-regulatory region of a heat-shock protein 70 gene to heat-inducible gene expression in the ascidian Ciona intestinalis.

    PubMed

    Kawaguchi, Akane; Utsumi, Nanami; Morita, Maki; Ohya, Aya; Wada, Shuichi

    2015-01-01

    Temporally controlled induction of gene expression is a useful technique for analyzing gene function. To make such a technique possible in Ciona intestinalis embryos, we employed the cis-regulatory region of the heat-shock protein 70 (HSP70) gene Ci-HSPA1/6/7-like for heat-inducible gene expression in C. intestinalis embryos. We showed that Ci-HSPA1/6/7-like becomes heat shock-inducible by the 32-cell stage during embryogenesis. The 5'-upstream region of Ci-HSPA1/6/7-like, which contains heat-shock elements indispensable for heat-inducible gene expression, induces the heat shock-dependent expression of a reporter gene in the whole embryo from the 32-cell to the middle gastrula stages and in progressively restricted areas of embryos in subsequent stages. We assessed the effects of heat-shock treatments in different conditions on the normality of embryos and induction of transgene expression. We evaluated the usefulness of this technique through overexpression experiments on the well-characterized, developmentally relevant gene, Ci-Bra, and showed that this technique is applicable for inferring the gene function in C. intestinalis.

  14. Fluorescent in situ hybridization to ascidian chromosomes.

    PubMed

    Shoguchi, Eiichi; Ikuta, Tetsuro; Yoshizaki, Fumiko; Satou, Yutaka; Satoh, Nori; Asano, Katsutoshi; Saiga, Hidetoshi; Nishikata, Takahito

    2004-02-01

    The draft genome of the ascidian Ciona intestinalis has been sequenced. Mapping of the genome sequence to the Ciona 14 haploid chromosomes is essential for future studies of the genome-wide control of gene expression in this basal chordate. Here we describe an efficient protocol for fluorescent in situ hybridization for mapping genes to the Ciona chromosomes. We demonstrate how the locations of two BAC clones can be mapped relative to each other. We also show that this method is efficient for coupling two so-far independent scaffolds into one longer scaffold when two BAC clones represent sequences located at either end of the two scaffolds.

  15. Transcriptional enhancers in ascidian development.

    PubMed

    Wang, Wei; Christiaen, Lionel

    2012-01-01

    The study of cis-regulatory DNAs that control developmental gene expression is integral to the modeling of comprehensive genomic regulatory networks for embryogenesis. Ascidian embryos provide a unique opportunity for the analysis of cis-regulatory DNAs with cellular resolution in the context of a simple but typical chordate body plan. Here, we review landmark studies that have laid the foundations for the study of transcriptional enhancers, among other cis-regulatory DNAs, and their roles in ascidian development. The studies using ascidians of the Ciona genus have capitalized on a unique electroporation technique that permits the simultaneous transfection of hundreds of fertilized eggs, which develop rapidly and express transgenes with little mosaicism. Current studies using the ascidian embryo benefit from extensively annotated genomic resources to characterize transcript models in silico. The search for functional noncoding sequences can be guided by bioinformatic analyses combining evolutionary conservation, gene coexpression, and combinations of overrepresented short-sequence motifs. The power of the transient transfection assays has allowed thorough dissection of numerous cis-regulatory modules, which provided insights into the functional constraints that shape enhancer architecture and diversification. Future studies will benefit from pioneering stable transgenic lines and the analysis of chromatin states. Whole genome expression, functional and DNA binding data are being integrated into comprehensive genomic regulatory network models of early ascidian cell specification with a single-cell resolution that is unique among chordate model systems.

  16. Development and evolution of the ascidian cardiogenic mesoderm.

    PubMed

    Tolkin, Theadora; Christiaen, Lionel

    2012-01-01

    The heart and other blood pumping organs are close to being universally essential in the animal kingdom. These organs present a large anatomical, morphological, and cellular diversity, which is thought to have arisen by building developmental modules on a conserved core of ancestral heart regulatory units. In this context, studies using the ascidian model system Ciona intestinalis offer a distinctive set of theoretical and experimental advantages, which we herein discuss in details. Development of the heart and related muscles in Ciona has been analyzed with a cellular to subcellular resolution unprecedented in Chordate model systems. Unique derived developmental characters of the cardiogenic mesoderm appear to be shared between Ciona and vertebrates. Notably, accumulating evidence point to an early Chordate origin of the cardiopharyngeal population of mesoderm cells that may have provided the foundation for the emergence of the second heart field in higher vertebrates.

  17. Ascidians as a vertebrate-like model organism for physiological studies of Rho GTPase signaling.

    PubMed

    Philips, Alexandre; Blein, Marion; Robert, Agnès; Chambon, Jean-Philippe; Baghdiguian, Stephen; Weill, Mylène; Fort, Philippe

    2003-07-01

    GTPases of the Rho family are evolutionarily conserved proteins that control cell shape dynamics during physiological processes as diverse as cell migration and polarity, axon outgrowth and guidance, apoptosis and phagocytosis. In mammals, 18 Rho proteins are distributed in 7 subfamilies. Rho, Rac and Cdc42 are the best-characterized ones, benefiting from the use of worm and drosophila, which only express these 3 subfamilies. An additional model would therefore help understand the physiological role of other mammalian subfamilies. We identified in genome databases the complete Rho family of two ascidians, Ciona intestinalis and Ciona savignyi, and showed that these families contain single ancestors of most mammalian Rho subfamilies. In Ciona intestinalis, all Rho genes are expressed and display specific developmental variations of mRNA expression during tadpole formation. Although C. intestinalis expresses five additional Rac compared to the closely related Ciona savignyi, only two appeared fully active in functional assays. Last, we identified in Ciona intestinalis database more than 50 Rho regulators (RhoGEFs and RhoGAPs) and 20 effector targets, whose analysis further supports the notion that Rho signaling components are of comparable complexity in mammals and ascidians. Since the tadpole of ascidians combines vertebrate-like developmental features with reduced cell number, particularly adapted to evolutionary and developmental biology studies, our data advocate this model for physiological studies of Rho signaling pathways.

  18. Ciona intestinalis and Oxycomanthus japonicus, representatives of marine invertebrates.

    PubMed

    Sasakura, Yasunori; Inaba, Kazuo; Satoh, Nori; Kondo, Mariko; Akasaka, Koji

    2009-10-01

    The study of marine invertebrates is useful in various biological research fields. However, genetic analyses of these animals are limited, mainly due to difficulties in culturing them, and the genetic resources of marine invertebrates have not been organized. Recently, advances have been made in the study of two deuterostomes, an ascidian Ciona intestinalis and a feather star Oxycomanthus japonicus. The draft genome sequence of Ciona intestinalis has been determined, and its compact genome, which has less redundancy of genes compared with vertebrates, provides us with a useful experimental system for analyzing the functions of genes during development. The life cycle of Ciona intestinalis is approximately 2-3 months, and the genetic techniques including a perfect inland culture system, germline transformation with a transposon Minos, enhancer detection and insertional mutagenesis, have been established. The feather star Oxycomanthus japonicus conserves the characteristics of the basic echinoderm body plan with a segmented mesoderm, which is a fascinating characteristic for understanding the evolution of echinoderms. Oxycomanthus japonicus shows strong regeneration ability and is a suitable subject for analysis of the mechanisms of regeneration. In consideration of these features, the National BioResource Project (NBRP) has started to support the supply of wild-types, transgenic lines and inbred lines of Ciona intestinalis and Oxycomanthus japonicus. PMID:19897929

  19. Gene expression profiles of FABP genes in protochordates, Ciona intestinalis and Branchiostoma belcheri.

    PubMed

    Orito, Wataru; Ohhira, Fuyuko; Ogasawara, Michio

    2015-11-01

    Fatty-acid-binding proteins (FABPs) are small intracellular proteins associated with the transportation of fatty acids. Members of the FABPs share similar amino acid sequences and tertiary structures and form, together with a member of the cellular retinol-binding proteins (CRBPs), the intracellular-lipid-binding protein (iLBP) family. In vertebrates, several types of FABP have been isolated and classified into three subfamilies: 2-4. In invertebrates, several FABP-related proteins have been reported in protostomes and amphioxus; however, little is known about the relationship between their phylogenetic positions and expression patterns. We have performed a genome-wide survey of FABP-related genes in protochordates: amphioxus Branchiostoma belcheri and the ascidian Ciona intestinalis. Comprehensive BLAST searches in NCBI and the Ciona Ghost Database by using amino acid sequences of all FABPs have revealed that the ascidian C. intestinalis and amphioxus B. belcheri contain six and seven FABP-related genes in their haploid genomes, respectively. Expression pattern analyses by whole-mount in situ hybridization in Ciona transparent juveniles and serial-section in situ hybridizations in adult amphioxus have revealed that all genes are mainly expressed in the postpharyngeal digestive tract. In particular, the expression of FABP-related genes of subfamily-2 (liver/ileum type) and subfamily-3 (intestinal type) in the ascidian pyloric gland and amphioxus hepatic cecum provides insight into the evolution of hepatic-related structures of chordates and FABP-related genes.

  20. Gene expression profiles of FABP genes in protochordates, Ciona intestinalis and Branchiostoma belcheri.

    PubMed

    Orito, Wataru; Ohhira, Fuyuko; Ogasawara, Michio

    2015-11-01

    Fatty-acid-binding proteins (FABPs) are small intracellular proteins associated with the transportation of fatty acids. Members of the FABPs share similar amino acid sequences and tertiary structures and form, together with a member of the cellular retinol-binding proteins (CRBPs), the intracellular-lipid-binding protein (iLBP) family. In vertebrates, several types of FABP have been isolated and classified into three subfamilies: 2-4. In invertebrates, several FABP-related proteins have been reported in protostomes and amphioxus; however, little is known about the relationship between their phylogenetic positions and expression patterns. We have performed a genome-wide survey of FABP-related genes in protochordates: amphioxus Branchiostoma belcheri and the ascidian Ciona intestinalis. Comprehensive BLAST searches in NCBI and the Ciona Ghost Database by using amino acid sequences of all FABPs have revealed that the ascidian C. intestinalis and amphioxus B. belcheri contain six and seven FABP-related genes in their haploid genomes, respectively. Expression pattern analyses by whole-mount in situ hybridization in Ciona transparent juveniles and serial-section in situ hybridizations in adult amphioxus have revealed that all genes are mainly expressed in the postpharyngeal digestive tract. In particular, the expression of FABP-related genes of subfamily-2 (liver/ileum type) and subfamily-3 (intestinal type) in the ascidian pyloric gland and amphioxus hepatic cecum provides insight into the evolution of hepatic-related structures of chordates and FABP-related genes. PMID:25957647

  1. Ciona as a Simple Chordate Model for Heart Development and Regeneration

    PubMed Central

    Anderson, Heather Evans; Christiaen, Lionel

    2016-01-01

    Cardiac cell specification and the genetic determinants that govern this process are highly conserved among Chordates. Recent studies have established the importance of evolutionarily-conserved mechanisms in the study of congenital heart defects and disease, as well as cardiac regeneration. As a basal Chordate, the Ciona model system presents a simple scaffold that recapitulates the basic blueprint of cardiac development in Chordates. Here we will focus on the development and cellular structure of the heart of the ascidian Ciona as compared to other Chordates, principally vertebrates. Comparison of the Ciona model system to heart development in other Chordates presents great potential for dissecting the genetic mechanisms that underlie congenital heart defects and disease at the cellular level and might provide additional insight into potential pathways for therapeutic cardiac regeneration.

  2. Ciona as a Simple Chordate Model for Heart Development and Regeneration

    PubMed Central

    Anderson, Heather Evans; Christiaen, Lionel

    2016-01-01

    Cardiac cell specification and the genetic determinants that govern this process are highly conserved among Chordates. Recent studies have established the importance of evolutionarily-conserved mechanisms in the study of congenital heart defects and disease, as well as cardiac regeneration. As a basal Chordate, the Ciona model system presents a simple scaffold that recapitulates the basic blueprint of cardiac development in Chordates. Here we will focus on the development and cellular structure of the heart of the ascidian Ciona as compared to other Chordates, principally vertebrates. Comparison of the Ciona model system to heart development in other Chordates presents great potential for dissecting the genetic mechanisms that underlie congenital heart defects and disease at the cellular level and might provide additional insight into potential pathways for therapeutic cardiac regeneration. PMID:27642586

  3. The influence of substrate material on ascidian larval settlement.

    PubMed

    Chase, Anna L; Dijkstra, Jennifer A; Harris, Larry G

    2016-05-15

    Submerged man-made structures present novel habitat for marine organisms and often host communities that differ from those on natural substrates. Although many factors are known to contribute to these differences, few studies have directly examined the influence of substrate material on organism settlement. We quantified larval substrate preferences of two species of ascidians, Ciona intestinalis (cryptogenic, formerly C. intestinalis type B) and Botrylloides violaceus (non-native), on commonly occurring natural (granite) and man-made (concrete, high-density polyethylene, PVC) marine materials in laboratory trials. Larvae exhibited species-specific settlement preferences, but generally settled more often than expected by chance on concrete and HDPE. Variation in settlement between materials may reflect preferences for rougher substrates, or may result from the influence of leached chemicals on ascidian settlement. These findings indicate that an experimental plate material can influence larval behavior and may help us understand how substrate features may contribute to differences in settlement in the field. PMID:27039957

  4. The influence of substrate material on ascidian larval settlement.

    PubMed

    Chase, Anna L; Dijkstra, Jennifer A; Harris, Larry G

    2016-05-15

    Submerged man-made structures present novel habitat for marine organisms and often host communities that differ from those on natural substrates. Although many factors are known to contribute to these differences, few studies have directly examined the influence of substrate material on organism settlement. We quantified larval substrate preferences of two species of ascidians, Ciona intestinalis (cryptogenic, formerly C. intestinalis type B) and Botrylloides violaceus (non-native), on commonly occurring natural (granite) and man-made (concrete, high-density polyethylene, PVC) marine materials in laboratory trials. Larvae exhibited species-specific settlement preferences, but generally settled more often than expected by chance on concrete and HDPE. Variation in settlement between materials may reflect preferences for rougher substrates, or may result from the influence of leached chemicals on ascidian settlement. These findings indicate that an experimental plate material can influence larval behavior and may help us understand how substrate features may contribute to differences in settlement in the field.

  5. Divergent mechanisms regulate conserved cardiopharyngeal development and gene expression in distantly related ascidians

    PubMed Central

    Stolfi, Alberto; Lowe, Elijah K; Racioppi, Claudia; Ristoratore, Filomena; Brown, C Titus; Swalla, Billie J; Christiaen, Lionel

    2014-01-01

    Ascidians present a striking dichotomy between conserved phenotypes and divergent genomes: embryonic cell lineages and gene expression patterns are conserved between distantly related species. Much research has focused on Ciona or Halocynthia spp. but development in other ascidians remains poorly characterized. In this study, we surveyed the multipotent myogenic B7.5 lineage in Molgula spp. Comparisons to the homologous lineage in Ciona revealed identical cell division and fate specification events that result in segregation of larval, cardiac, and pharyngeal muscle progenitors. Moreover, the expression patterns of key regulators are conserved, but cross-species transgenic assays uncovered incompatibility, or ‘unintelligibility’, of orthologous cis-regulatory sequences between Molgula and Ciona. These sequences drive identical expression patterns that are not recapitulated in cross-species assays. We show that this unintelligibility is likely due to changes in both cis- and trans-acting elements, hinting at widespread and frequent turnover of regulatory mechanisms underlying otherwise conserved aspects of ascidian embryogenesis. DOI: http://dx.doi.org/10.7554/eLife.03728.001 PMID:25209999

  6. Ascidian notochord morphogenesis

    PubMed Central

    Jiang, Di; Smith, William C.

    2010-01-01

    The development of the notochord involves a complex set of cellular behaviors. While these morphogenic behaviors are common to all chordates, the ascidian provides a particularly attractive experimental model because of its relative simplicity. In particular, all notochord morphogenesis in ascidians takes place with only 40 cells, as opposed to the hundreds of cells in vertebrate models systems. Initial steps in ascidian notochord development convert a monolayer of epithelial-like cells in the pre-gastrula embryo to a cylindrical rod of single-cell diameter. Convergent extension is responsible for the intercalation of notochord cells and some degree of notochord elongation, while a second phase of elongation is observed as the notochord narrows medially and increases in volume. The mechanism by which the volume of the notochord increases differs between ascidian species. Some ascidian species produce extracellular pockets that will eventually coalesce to form a lumen running the length of the notochord, while others appear to make intercellular vacuoles. By either mechanism, the resulting notochord serves as a hydrostatic skeleton allowing for the locomotion of the swimming larva. Several basic cell behaviors, such as cell shape changes, cell rearrangement, establishment of cell polarity, and alteration of extracellular environment, are displayed in the process of notochord morphogenesis. Modern analysis of ascidian notochord morphogenesis promises to contribute to our understanding of these fundamental biological processes. PMID:17497687

  7. Metamorphosis in solitary ascidians.

    PubMed

    Karaiskou, Anthi; Swalla, Billie J; Sasakura, Yasunori; Chambon, Jean-Philippe

    2015-01-01

    Embryonic and postembryonic development in ascidians have been studied for over a century, but it is only in the last 10 years that the complex molecular network involved in coordinating postlarval development and metamorphosis has started to emerge. In most ascidians, the transition from the larval to the sessile juvenile/adult stage, or metamorphosis, requires a combination of environmental and endogenous signals and is characterized by coordinated global morphogenetic changes that are initiated by the adhesion of the larvae. Cloney was the first to describe cellular events of ascidians' metamorphosis in 1978 and only recently elements of the molecular regulation of this crucial developmental step have been revealed. This review aims to present a thorough view of this crucial developmental step by combining recent molecular data to the already established cellular events.

  8. Diverse ETS transcription factors mediate FGF signaling in the Ciona anterior neural plate.

    PubMed

    Gainous, T Blair; Wagner, Eileen; Levine, Michael

    2015-03-15

    The ascidian Ciona intestinalis is a marine invertebrate belonging to the sister group of the vertebrates, the tunicates. Its compact genome and simple, experimentally tractable embryos make Ciona well-suited for the study of cell-fate specification in chordates. Tunicate larvae possess a characteristic chordate body plan, and many developmental pathways are conserved between tunicates and vertebrates. Previous studies have shown that FGF signals are essential for neural induction and patterning at sequential steps of Ciona embryogenesis. Here we show that two different ETS family transcription factors, Ets1/2 and Elk1/3/4, have partially redundant activities in the anterior neural plate of gastrulating embryos. Whereas Ets1/2 promotes pigment cell formation in lateral lineages, both Ets1/2 and Elk1/3/4 are involved in the activation of Myt1L in medial lineages and the restriction of Six3/6 expression to the anterior-most regions of the neural tube. We also provide evidence that photoreceptor cells arise from posterior regions of the presumptive sensory vesicle, and do not depend on FGF signaling. Cells previously identified as photoreceptor progenitors instead form ependymal cells and neurons of the larval brain. Our results extend recent findings on FGF-dependent patterning of anterior-posterior compartments in the Ciona central nervous system.

  9. Anterior-posterior regionalized gene expression in the Ciona notochord

    PubMed Central

    Veeman, Michael

    2014-01-01

    Background In the simple ascidian chordate Ciona the signaling pathways and gene regulatory networks giving rise to initial notochord induction are largely understood and the mechanisms of notochord morphogenesis are being systematically elucidated. The notochord has generally been thought of as a non-compartmentalized or regionalized organ that is not finely patterned at the level of gene expression. Quantitative imaging methods have recently shown, however, that notochord cell size, shape and behavior vary consistently along the anterior-posterior (AP) axis. Results Here we screen candidate genes by whole mount in situ hybridization for potential AP asymmetry. We identify 4 genes that show non-uniform expression in the notochord. Ezrin/radixin/moesin (ERM) is expressed more strongly in the secondary notochord lineage than the primary. CTGF is expressed stochastically in a subset of notochord cells. A novel calmodulin-like gene (BCamL) is expressed more strongly at both the anterior and posterior tips of the notochord. A TGF-β ortholog is expressed in a gradient from posterior to anterior. The asymmetries in ERM, BCamL and TGF-β expression are evident even before the notochord cells have intercalated into a single-file column. Conclusions We conclude that the Ciona notochord is not a homogeneous tissue but instead shows distinct patterns of regionalized gene expression. PMID:24288133

  10. Natural Variation of Model Mutant Phenotypes in Ciona intestinalis

    PubMed Central

    Brown, Euan R.; Leccia, Nicola I.; Squarzoni, Paola; Tarallo, Raffaella; Alfano, Christian; Caputi, Luigi; D'Ambrosio, Palmira; Daniele, Paola; D'Aniello, Enrico; D'Aniello, Salvatore; Maiella, Sylvie; Miraglia, Valentina; Russo, Monia Teresa; Sorrenti, Gerarda; Branno, Margherita; Cariello, Lucio; Cirino, Paola; Locascio, Annamaria; Spagnuolo, Antonietta; Zanetti, Laura; Ristoratore, Filomena

    2008-01-01

    Background The study of ascidians (Chordata, Tunicata) has made a considerable contribution to our understanding of the origin and evolution of basal chordates. To provide further information to support forward genetics in Ciona intestinalis, we used a combination of natural variation and neutral population genetics as an approach for the systematic identification of new mutations. In addition to the significance of developmental variation for phenotype-driven studies, this approach can encompass important implications in evolutionary and population biology. Methodology/Principal Findings Here, we report a preliminary survey for naturally occurring mutations in three geographically interconnected populations of C. intestinalis. The influence of historical, geographical and environmental factors on the distribution of abnormal phenotypes was assessed by means of 12 microsatellites. We identified 37 possible mutant loci with stereotyped defects in embryonic development that segregate in a way typical of recessive alleles. Local populations were found to differ in genetic organization and frequency distribution of phenotypic classes. Conclusions/Significance Natural genetic polymorphism of C. intestinalis constitutes a valuable source of phenotypes for studying embryonic development in ascidians. Correlating genetic structure and the occurrence of abnormal phenotypes is a crucial focus for understanding the selective forces that shape natural finite populations, and may provide insights of great importance into the evolutionary mechanisms that generate animal diversity. PMID:18523552

  11. ANISEED 2015: a digital framework for the comparative developmental biology of ascidians

    PubMed Central

    Brozovic, Matija; Martin, Cyril; Dantec, Christelle; Dauga, Delphine; Mendez, Mickaël; Simion, Paul; Percher, Madeline; Laporte, Baptiste; Scornavacca, Céline; Di Gregorio, Anna; Fujiwara, Shigeki; Gineste, Mathieu; Lowe, Elijah K.; Piette, Jacques; Racioppi, Claudia; Ristoratore, Filomena; Sasakura, Yasunori; Takatori, Naohito; Brown, Titus C.; Delsuc, Frédéric; Douzery, Emmanuel; Gissi, Carmela; McDougall, Alex; Nishida, Hiroki; Sawada, Hitoshi; Swalla, Billie J.; Yasuo, Hitoyoshi; Lemaire, Patrick

    2016-01-01

    Ascidians belong to the tunicates, the sister group of vertebrates and are recognized model organisms in the field of embryonic development, regeneration and stem cells. ANISEED is the main information system in the field of ascidian developmental biology. This article reports the development of the system since its initial publication in 2010. Over the past five years, we refactored the system from an initial custom schema to an extended version of the Chado schema and redesigned all user and back end interfaces. This new architecture was used to improve and enrich the description of Ciona intestinalis embryonic development, based on an improved genome assembly and gene model set, refined functional gene annotation, and anatomical ontologies, and a new collection of full ORF cDNAs. The genomes of nine ascidian species have been sequenced since the release of the C. intestinalis genome. In ANISEED 2015, all nine new ascidian species can be explored via dedicated genome browsers, and searched by Blast. In addition, ANISEED provides full functional gene annotation, anatomical ontologies and some gene expression data for the six species with highest quality genomes. ANISEED is publicly available at: http://www.aniseed.cnrs.fr. PMID:26420834

  12. ANISEED 2015: a digital framework for the comparative developmental biology of ascidians.

    PubMed

    Brozovic, Matija; Martin, Cyril; Dantec, Christelle; Dauga, Delphine; Mendez, Mickaël; Simion, Paul; Percher, Madeline; Laporte, Baptiste; Scornavacca, Céline; Di Gregorio, Anna; Fujiwara, Shigeki; Gineste, Mathieu; Lowe, Elijah K; Piette, Jacques; Racioppi, Claudia; Ristoratore, Filomena; Sasakura, Yasunori; Takatori, Naohito; Brown, Titus C; Delsuc, Frédéric; Douzery, Emmanuel; Gissi, Carmela; McDougall, Alex; Nishida, Hiroki; Sawada, Hitoshi; Swalla, Billie J; Yasuo, Hitoyoshi; Lemaire, Patrick

    2016-01-01

    Ascidians belong to the tunicates, the sister group of vertebrates and are recognized model organisms in the field of embryonic development, regeneration and stem cells. ANISEED is the main information system in the field of ascidian developmental biology. This article reports the development of the system since its initial publication in 2010. Over the past five years, we refactored the system from an initial custom schema to an extended version of the Chado schema and redesigned all user and back end interfaces. This new architecture was used to improve and enrich the description of Ciona intestinalis embryonic development, based on an improved genome assembly and gene model set, refined functional gene annotation, and anatomical ontologies, and a new collection of full ORF cDNAs. The genomes of nine ascidian species have been sequenced since the release of the C. intestinalis genome. In ANISEED 2015, all nine new ascidian species can be explored via dedicated genome browsers, and searched by Blast. In addition, ANISEED provides full functional gene annotation, anatomical ontologies and some gene expression data for the six species with highest quality genomes. ANISEED is publicly available at: http://www.aniseed.cnrs.fr. PMID:26420834

  13. ANISEED 2015: a digital framework for the comparative developmental biology of ascidians.

    PubMed

    Brozovic, Matija; Martin, Cyril; Dantec, Christelle; Dauga, Delphine; Mendez, Mickaël; Simion, Paul; Percher, Madeline; Laporte, Baptiste; Scornavacca, Céline; Di Gregorio, Anna; Fujiwara, Shigeki; Gineste, Mathieu; Lowe, Elijah K; Piette, Jacques; Racioppi, Claudia; Ristoratore, Filomena; Sasakura, Yasunori; Takatori, Naohito; Brown, Titus C; Delsuc, Frédéric; Douzery, Emmanuel; Gissi, Carmela; McDougall, Alex; Nishida, Hiroki; Sawada, Hitoshi; Swalla, Billie J; Yasuo, Hitoyoshi; Lemaire, Patrick

    2016-01-01

    Ascidians belong to the tunicates, the sister group of vertebrates and are recognized model organisms in the field of embryonic development, regeneration and stem cells. ANISEED is the main information system in the field of ascidian developmental biology. This article reports the development of the system since its initial publication in 2010. Over the past five years, we refactored the system from an initial custom schema to an extended version of the Chado schema and redesigned all user and back end interfaces. This new architecture was used to improve and enrich the description of Ciona intestinalis embryonic development, based on an improved genome assembly and gene model set, refined functional gene annotation, and anatomical ontologies, and a new collection of full ORF cDNAs. The genomes of nine ascidian species have been sequenced since the release of the C. intestinalis genome. In ANISEED 2015, all nine new ascidian species can be explored via dedicated genome browsers, and searched by Blast. In addition, ANISEED provides full functional gene annotation, anatomical ontologies and some gene expression data for the six species with highest quality genomes. ANISEED is publicly available at: http://www.aniseed.cnrs.fr.

  14. Evolutionary origins of the vertebrate heart: Specification of the cardiac lineage in Ciona intestinalis

    PubMed Central

    Davidson, Brad; Levine, Michael

    2003-01-01

    Here we exploit the extensive cell lineage information and streamlined genome of the ascidian, Ciona intestinalis, to investigate heart development in a basal chordate. Several cardiac genes were analyzed, including the sole Ciona ortholog of the Drosophila tinman gene, and tissue-specific enhancers were isolated for some of the genes. Conserved sequence motifs within these enhancers facilitated the isolation of a heart enhancer for the Ciona Hand-like gene. Altogether, these studies provide a regulatory framework for the differentiation of the cardiac mesoderm, beginning at the 110-cell stage, and extending through the fusion of cardiac progenitors during tail elongation. The cardiac lineage shares a common origin with the germ line, and zygotic transcription is first detected in the heart progenitors only after its separation from the germ line at the 64-cell stage. We propose that germ-line determinants influence the specification of the cardiac mesoderm, both by inhibiting inductive signals required for the development of noncardiac mesoderm lineages, and by providing a localized source of Wnt-5 and other signals required for heart development. We discuss the possibility that the germ line also influences the specification of the vertebrate heart. PMID:14500781

  15. Screening of ovarian steroidogenic pathway in Ciona intestinalis and its modulation after tributyltin exposure

    SciTech Connect

    Cangialosi, Maria Vittoria; Puccia, Egidio; Mazzola, Antonio; Mansueto, Valentina; Arukwe, Augustine

    2010-05-15

    In this study, we have identified several ovarian steroids in Ciona with high similarity to vertebrate steroids and showed that cholesterol, corticosterone, dehydroepiandrosterone, estrone, estradiol-17beta, testosterone, pregnenolone, progesterone, have identical molecular spectra with vertebrate steroids. In addition, we have studied the effects of an endocrine disruptor (tributyltin: TBT) on these sex hormones and their precursors, ovarian morphology, and gene expression of some key enzymes in steroidogenic pathway in the ovary of Ciona. Ovarian specimens were cultured in vitro using different concentrations of TBT (10{sup -5}, 10{sup -4} and 10{sup -3} M). Ethanol was used as solvent control. Gene expression analysis was performed for adrenodoxin (ADREN) and adrenodoxin reductase (ADOX) (mediators of acute steroidogenesis) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD). These transcripts were detected and measured by quantitative (real-time) polymerase chain reaction (qPCR). Sex steroids and their precursors were identified and quantified by a gas chromatography-mass spectroscopy (GC-MS) method. Exposure of Ciona ovaries to TBT produced modulations (either increased or decreased) of sterols and sex steroid levels, whereas no significant differences in ADREN, ADOX or 17beta-HSD mRNA expression patterns were observed. Histological analysis shows that TBT produced several modifications on Ciona ovarian morphology that includes irregular outline of nuclear membrane, less compacted cytoplasm, in addition to test and granulosa cells that were detached from the oocyte membrane. Given that the ascidians represent very simple experimental models for the study of endocrine disruption by environmental contaminants, our findings provide excellent models for multiple identification and quantification of sex steroid and their precursors in biological samples exposed to endocrine-disrupting chemicals and for direct extrapolation of such effects across taxonomic groups

  16. The Ciona intestinalis genome: when the constraints are off

    NASA Technical Reports Server (NTRS)

    Holland, Linda Z.; Gibson-Brown, Jeremy J.

    2003-01-01

    The recent genome sequencing of a non-vertebrate deuterostome, the ascidian tunicate Ciona intestinalis, makes a substantial contribution to the fields of evolutionary and developmental biology.1 Tunicates have some of the smallest bilaterian genomes, embryos with relatively few cells, fixed lineages and early determination of cell fates. Initial analyses of the C. intestinalis genome indicate that it has been evolving rapidly. Comparisons with other bilaterians show that C. intestinalis has lost a number of genes, and that many genes linked together in most other bilaterians have become uncoupled. In addition, a number of independent, lineage-specific gene duplications have been detected. These new results, although interesting in themselves, will take on a deeper significance once the genomes of additional invertebrate deuterostomes (e.g. echinoderms, hemichordates and amphioxus) have been sequenced. With such a broadened database, comparative genomics can begin to ask pointed questions about the relationship between the evolution of genomes and the evolution of body plans. Copyright 2003 Wiley Periodicals, Inc.

  17. THALIACEANS, THE NEGLECTED PELAGIC RELATIVES OF ASCIDIANS: A DEVELOPMENTAL AND EVOLUTIONARY ENIGMA.

    PubMed

    Piette, Jacques; Lemaire, Patrick

    2015-06-01

    Most developmental biologists equate tunicates to the sessile ascidians, including Ciona intestinalis, and the pelagic appendicularians, in particular Oikopleura dioica. However, there exists a third group of tunicates with a pelagic lifestyle, the thaliaceans, which include salps, pyrosomes, and doliolids. Although thaliaceans have raised the curiosity offamous zoologists since the 18th century, the difficulty of observing and experimentally manipulating them has led to many controversies and speculations about their life cycles and developmental strategies, the phylogenetic relationship within the group and with other tunicates, and the drivers of speciation in these widely distributed animals living in a seemingly uniform environment. Here, we take a historical perspective to summarize 250 years of work on this intriguing group of animals, and explore how modern genomics and imaging approaches are starting to solve fascinating evolutionary and developmental riddles. Recent molecular analyses support previous morphological evidence that ascidians are not monophyletic and that thaliaceans evolved from a sessile ascidian-like ancestor. In parallel, preliminary live-imaging and gene-expression data offer exciting entry points to understand how the adoption of a pelagic lifestyle led to drastic modifications in the morphology, embryology, and life cycle of these tunicates, compared to their sessile ancestor. PMID:26285352

  18. Further EST analysis of endocrine genes that are preferentially expressed in the neural complex of Ciona intestinalis: receptor and enzyme genes associated with endocrine system in the neural complex.

    PubMed

    Sekiguchi, Toshio; Kawashima, Takeshi; Satou, Yutaka; Satoh, Nori

    2007-01-15

    Identification of orthologs of vertebrate neuropeptides and hypothalamic hormones in the neural complex of ascidians suggests integral roles of the ascidian neural complex in the endocrine system. In the present study, we investigated endocrine-related genes expressed in the neural complex of Ciona intestinalis. Comprehensive analyses of 3'-end sequences of the neural complex cDNAs placed 10,029 clones into 4051 independent clusters or genes, 1524 of them being expressed preferentially in this organ. Comparison of the 1524 genes with the human proteome databank demonstrated that 476 matched previously identified human proteins with distinct functions. Further analyses of sequence similarity of the 476 genes demonstrated that 21 genes are candidates for those involved in the endocrine system. Although we cannot detect hormone or peptide candidates, we found 21 genes such as receptors for peptide ligands, receptor-modulating proteins, and processing enzymes. We then characterized the Ciona prohormone convertase 2 (Ci-PC2) and carboxypeptidase E (Ci-CPE), which are associated with endoproteolytic processing of peptide hormone precursors. Furthermore, genes encoding these transcripts are expressed specifically in the neural complex of young adult ascidians. These data provide the molecular basis for further functional studies of the endocrine role of the neural complex of ascidians.

  19. 3D-Printed Microwell Arrays for Ciona Microinjection and Timelapse Imaging

    PubMed Central

    Gregory, Clint; Veeman, Michael

    2013-01-01

    Ascidians such as Ciona are close chordate relatives of the vertebrates with small, simple embryonic body plans and small, simple genomes. The tractable size of the embryo offers considerable advantages for in toto imaging and quantitative analysis of morphogenesis. For functional studies, Ciona eggs are considerably more challenging to microinject than the much larger eggs of other model organisms such as zebrafish and Xenopus. One of the key difficulties is in restraining the eggs so that the microinjection needle can be easily introduced and withdrawn. Here we develop and test a device to cast wells in agarose that are each sized to hold a single egg. This injection mold is fabricated by micro-resolution stereolithography with a grid of egg-sized posts that cast corresponding wells in agarose. This 3D printing technology allows the rapid and inexpensive testing of iteratively refined prototypes. In addition to their utility in microinjection, these grids of embryo-sized wells are also valuable for timelapse imaging of multiple embryos. PMID:24324769

  20. Chemical defense against fouling in the solitary ascidian Phallusia nigra.

    PubMed

    Mayzel, Boaz; Haber, Markus; Ilan, Micha

    2014-12-01

    The solitary ascidian Phallusia nigra is rarely fouled by epibionts. Here, we tested the antifouling activity of its crude extracts in laboratory and field assays. P. nigra extracts inhibited the growth of all eight tested environmental bacteria and two of four laboratory bacteria. Extracts of the sympatric, but fouled solitary ascidian Herdmania momus inhibited only one test bacterium. Scanning electron microscopy confirmed that the tunic surface of P. nigra is largely bacteria-free. Both ascidian extracts significantly inhibited the larval metamorphosis of the bryozoan Bugula neritina at the tested concentration range of 0.05-2 mg ml(-1). Both crude extracts were toxic to larvae of the brine shrimp Artemia salina at natural volumetric whole-tissue concentrations, but only P. nigra showed activity at 2 mg ml(-1) and below (LC50 = 1.11 mg ml(-1)). P. nigra crude extracts also significantly reduced the settlement of barnacles, polychaetes, and algae in Mediterranean field assays and barnacle settlement in Red Sea trials. Comparisons between control experiments and pH values monitored in all experiments indicate that the observed effects were not due to acidity of the organic extracts. Our results show that P. nigra secondary metabolites have antifouling activities, which may act in synergy with previously proposed physiological antifouling mechanisms. PMID:25572211

  1. Temporal stability of bacterial symbionts in a temperate ascidian

    PubMed Central

    López-Legentil, Susanna; Turon, Xavier; Espluga, Roger; Erwin, Patrick M.

    2015-01-01

    In temperate seas, both bacterioplankton communities and invertebrate lifecycles follow a seasonal pattern. To investigate whether the bacterial community associated with the Mediterranean ascidian Didemnum fulgens exhibited similar variations, we monitored its bacterial community structure monthly for over a year using terminal restriction fragment length polymorphism and clone library analyses based on a nearly full length fragment of the 16S rRNA gene. D. fulgens harbored a bacterial consortium typical of ascidians, including numerous members of the phylum Proteobacteria, and a few members of the phyla Cyanobacteria and Acidobacteria. The overall bacterial community in D. fulgens had a distinct signature from the surrounding seawater and was stable over time and across seasonal fluctuations in temperature. Bacterial symbionts were also observed around animal cells in the tunic of adult individuals and in the inner tunic of D. fulgens larvae by transmission electron microscopy. Our results suggest that, as seen for sponges and corals, some species of ascidians host stable and unique bacterial communities that are at least partially inherited by their progeny by vertical transmission. PMID:26441944

  2. A standardisation of Ciona intestinalis (Chordata, Ascidiacea) embryo-larval bioassay for ecotoxicological studies.

    PubMed

    Bellas, Juan; Beiras, Ricardo; Vázquez, Elsa

    2003-11-01

    A standardisation of the ascidian Ciona intestinalis embryo-larval bioassay for marine pollution assessment has been developed. The minimum percentage of embryogenesis success was established to assess the quality of the biological material used; minimum sample size and number of replicates per treatment were also estimated. The suitability of artificial and natural seawater for the incubation of ascidian embryos and larvae was compared, and the optimum conditions of temperature, salinity, pH, density of embryos in the vials and the sperm/egg ratio were investigated. On the basis of the 10th percentile of the distribution of larval abnormalities, we proposed a threshold of 50% normal larvae in the control in order to consider the test of acceptable biological quality. According to our results n=5 is a sufficiently high replication to detect 5% differences among treatment means with a power of P=90% and alpha=0.05, and a sampling size >/=222 allows a 95% confidence in the estimate with an error of 0.05. Egg density did not affect larval development within the range 1-20 eggs/ml, and the optimum sperm/egg ratio which fertilise 100% of the eggs was 3000-30,000 sperm/egg (i.e. 10(8)-10(7) sperm/ml). There were not significant differences between the two water types tested, and the optimum tolerance ranges were 18-23 degrees C temperature, 34-42 ppt salinity (42 ppt was the highest salinity tested), and 7.4-8.8 pH. The median effective concentration (EC(50)) of copper (Cu) causing a 50% reduction of normal hatched larvae was 54.2 microg/l (0.85 microM), which shows a sensitivity of this species similar to the commonly used bivalve and sea-urchin tests. The ascidian embryo-larval bioassay is an accurate, reliable, simple and rapid method that can be used in ecotoxicological studies.

  3. A standardisation of Ciona intestinalis (Chordata, Ascidiacea) embryo-larval bioassay for ecotoxicological studies.

    PubMed

    Bellas, Juan; Beiras, Ricardo; Vázquez, Elsa

    2003-11-01

    A standardisation of the ascidian Ciona intestinalis embryo-larval bioassay for marine pollution assessment has been developed. The minimum percentage of embryogenesis success was established to assess the quality of the biological material used; minimum sample size and number of replicates per treatment were also estimated. The suitability of artificial and natural seawater for the incubation of ascidian embryos and larvae was compared, and the optimum conditions of temperature, salinity, pH, density of embryos in the vials and the sperm/egg ratio were investigated. On the basis of the 10th percentile of the distribution of larval abnormalities, we proposed a threshold of 50% normal larvae in the control in order to consider the test of acceptable biological quality. According to our results n=5 is a sufficiently high replication to detect 5% differences among treatment means with a power of P=90% and alpha=0.05, and a sampling size >/=222 allows a 95% confidence in the estimate with an error of 0.05. Egg density did not affect larval development within the range 1-20 eggs/ml, and the optimum sperm/egg ratio which fertilise 100% of the eggs was 3000-30,000 sperm/egg (i.e. 10(8)-10(7) sperm/ml). There were not significant differences between the two water types tested, and the optimum tolerance ranges were 18-23 degrees C temperature, 34-42 ppt salinity (42 ppt was the highest salinity tested), and 7.4-8.8 pH. The median effective concentration (EC(50)) of copper (Cu) causing a 50% reduction of normal hatched larvae was 54.2 microg/l (0.85 microM), which shows a sensitivity of this species similar to the commonly used bivalve and sea-urchin tests. The ascidian embryo-larval bioassay is an accurate, reliable, simple and rapid method that can be used in ecotoxicological studies. PMID:14568047

  4. Ascidian Mitogenomics: Comparison of Evolutionary Rates in Closely Related Taxa Provides Evidence of Ongoing Speciation Events

    PubMed Central

    Griggio, Francesca; Voskoboynik, Ayelet; Iannelli, Fabio; Justy, Fabienne; Tilak, Marie-Ka; Xavier, Turon; Pesole, Graziano; Douzery, Emmanuel J.P.; Mastrototaro, Francesco; Gissi, Carmela

    2014-01-01

    Ascidians are a fascinating group of filter-feeding marine chordates characterized by rapid evolution of both sequences and structure of their nuclear and mitochondrial genomes. Moreover, they include several model organisms used to investigate complex biological processes in chordates. To study the evolutionary dynamics of ascidians at short phylogenetic distances, we sequenced 13 new mitogenomes and analyzed them, together with 15 other available mitogenomes, using a novel approach involving detailed whole-mitogenome comparisons of conspecific and congeneric pairs. The evolutionary rate was quite homogeneous at both intraspecific and congeneric level, and the lowest congeneric rates were found in cryptic (morphologically undistinguishable) and in morphologically very similar species pairs. Moreover, congeneric nonsynonymous rates (dN) were up to two orders of magnitude higher than in intraspecies pairs. Overall, a clear-cut gap sets apart conspecific from congeneric pairs. These evolutionary peculiarities allowed easily identifying an extraordinary intraspecific variability in the model ascidian Botryllus schlosseri, where most pairs show a dN value between that observed at intraspecies and congeneric level, yet consistently lower than that of the Ciona intestinalis cryptic species pair. These data suggest ongoing speciation events producing genetically distinct B. schlosseri entities. Remarkably, these ongoing speciation events were undetectable by the cox1 barcode fragment, demonstrating that, at low phylogenetic distances, the whole mitogenome has a higher resolving power than cox1. Our study shows that whole-mitogenome comparative analyses, performed on a suitable sample of congeneric and intraspecies pairs, may allow detecting not only cryptic species but also ongoing speciation events. PMID:24572017

  5. The identification of transcription factors expressed in the notochord of Ciona intestinalis adds new potential players to the Brachyury gene regulatory network

    PubMed Central

    José-Edwards, Diana S.; Kerner, Pierre; Kugler, Jamie E.; Deng, Wei; Jiang, Di; Di Gregorio, Anna

    2013-01-01

    The notochord is the distinctive characteristic of chordates; however, the knowledge of the complement of transcription factors governing the development of this structure is still incomplete. Here we present the expression patterns of seven transcription factor genes detected in the notochord of the ascidian Ciona intestinalis at various stages of embryonic development. Four of these transcription factors, Fos-a, NFAT5, AFF and Klf15, have not been directly associated with the notochord in previous studies, while the others, including Spalt-like-a, Lmx-like and STAT5/6-b, display evolutionarily conserved expression in this structure as well as in other domains. We examined the hierarchical relationships between these genes and the transcription factor Brachyury, which is necessary for notochord development in all chordates. We found that Ciona Brachyury regulates the expression of most, although not all, of these genes. These results shed light on the genetic regulatory program underlying notochord formation in Ciona and possibly other chordates. PMID:21594950

  6. Enhancer of zeste acts as a major developmental regulator of Ciona intestinalis embryogenesis

    PubMed Central

    Le Goff, Emilie; Martinand-Mari, Camille; Martin, Marianne; Feuillard, Jérôme; Boublik, Yvan; Godefroy, Nelly; Mangeat, Paul; Baghdiguian, Stephen; Cavalli, Giacomo

    2015-01-01

    ABSTRACT The paradigm of developmental regulation by Polycomb group (PcG) proteins posits that they maintain silencing outside the spatial expression domains of their target genes, particularly of Hox genes, starting from mid embryogenesis. The Enhancer of zeste [E(z)] PcG protein is the catalytic subunit of the PRC2 complex, which silences its targets via deposition of the H3K27me3 mark. Here, we studied the ascidian Ciona intestinalis counterpart of E(z). Ci-E(z) is detected by immunohistochemistry as soon as the 2- and 4-cell stages as a cytoplasmic form and becomes exclusively nuclear thereafter, whereas the H3K27me3 mark is detected starting from the gastrula stage and later. Morpholino invalidation of Ci-E(z) leads to the total disappearance of both Ci-E(z) protein and its H3K27me3 mark. Ci-E(z) morphants display a severe phenotype. Strikingly, the earliest defects occur at the 4-cell stage with the dysregulation of cell positioning and mitotic impairment. At later stages, Ci-E(z)-deficient embryos are affected by terminal differentiation defects of neural, epidermal and muscle tissues, by the failure to form a notochord and by the absence of caudal nerve. These major phenotypic defects are specifically rescued by injection of a morpholino-resistant Ci-E(z) mRNA, which restores expression of Ci-E(z) protein and re-deposition of the H3K27me3 mark. As observed by qPCR analyses, Ci-E(z) invalidation leads to the early derepression of tissue-specific developmental genes, whereas late-acting developmental genes are generally down-regulated. Altogether, our results suggest that Ci-E(z) plays a major role during embryonic development in Ciona intestinalis by silencing early-acting developmental genes in a Hox-independent manner. PMID:26276097

  7. Functional Brachyury Binding Sites Establish a Temporal Read-out of Gene Expression in the Ciona Notochord

    PubMed Central

    Passamaneck, Yale J.; Gazdoiu, Stefan; José-Edwards, Diana S.; Kugler, Jamie E.; Oda-Ishii, Izumi; Imai, Janice H.; Nibu, Yutaka; Di Gregorio, Anna

    2013-01-01

    The appearance of the notochord represented a milestone in Deuterostome evolution. The notochord is necessary for the development of the chordate body plan and for the formation of the vertebral column and numerous organs. It is known that the transcription factor Brachyury is required for notochord formation in all chordates, and that it controls transcription of a large number of target genes. However, studies of the structure of the cis-regulatory modules (CRMs) through which this control is exerted are complicated in vertebrates by the genomic complexity and the pan-mesodermal expression territory of Brachyury. We used the ascidian Ciona, in which the single-copy Brachyury is notochord-specific and CRMs are easily identifiable, to carry out a systematic characterization of Brachyury-downstream notochord CRMs. We found that Ciona Brachyury (Ci-Bra) controls most of its targets directly, through non-palindromic binding sites that function either synergistically or individually to activate early- and middle-onset genes, respectively, while late-onset target CRMs are controlled indirectly, via transcriptional intermediaries. These results illustrate how a transcriptional regulator can efficiently shape a shallow gene regulatory network into a multi-tiered transcriptional output, and provide insights into the mechanisms that establish temporal read-outs of gene expression in a fast-developing chordate embryo. PMID:24204212

  8. Ascidian tail formation requires caudal function.

    PubMed

    Katsuyama, Y; Sato, Y; Wada, S; Saiga, H

    1999-09-15

    Although the tail is one of the major characteristics of animals of the phylum Chordata, evolutionary aspects of the molecular mechanisms involved in its formation are not clear. To obtain insights into these issues, we have isolated and investigated the caudal gene of an ascidian, one of the lower animal groups among chordates. Ascidian caudal is expressed from the midgastrula stage onward in the lateral walls of the posterior neural tube cell lineage and also in the posterior epidermal cells from the neurula stage. Thus, ascidian caudal expression is restricted to the ectoderm of a tail-forming region throughout embryogenesis. Suppression of caudal function by an antisense oligonucleotide or a dominant negative construct caused inhibition of the cell movement required for tail formation. Overexpression of wild-type caudal mRNA in an ascidian animal cap, an animal half explant prepared at the eight-cell stage, caused elongation of the cap. Furthermore, Xenopus embryos injected with dominant negative ascidian caudal exhibited defects in elongation, suggesting a conserved caudal function among chordates. These results indicate that caudal function is required for chordate tail formation and may play a key role in its evolution. PMID:10479446

  9. Developmental toxicity of benzotriazole in the protochordate Ciona intestinalis (Chordata, Ascidiae).

    PubMed

    Kadar, Eniko; Dashfield, Sarah; Hutchinson, Thomas H

    2010-01-01

    Benzotriazoles (BT) are applied as anticorrosive and de-icing agents and have been detected in a variety of aquatic ecosystems and municipal wastewater effluents. We have assessed the developmental effects of benzotriazole (CAS number 95-14-7) to the marine invertebrate Ciona intestinalis (Chordata, Ascidiae). At 15 +/- 1 degrees C, the 24 h No-Observed Effect Concentration (NOEC) and Lowest Observed Effect Concentration (LOEC) values based on embryo morphological development were 100 and >100 mg L(-1), respectively (nominal concentration under static conditions). After 48 h, the NOEC and LOEC values were 10 and 32 mg L(-1), respectively. Light and electron microscopy studies on benzotriazole-exposed larva indicated that the primary target cells were the extra-embryonic test cells, which are known to play a significant apoptotic role during ascidian metamorphosis. The visible decline of test cells in benzotriazole-exposed larvae raises the possibility that the compound interferes with the regulation of embryo development in protochordates such as C. intestinalis. Further research is warranted to assess the potential longer term sublethal impacts of benzotriazole in aquatic organisms.

  10. Distinctive expression patterns of Hedgehog pathway genes in the Ciona intestinalis larva: implications for a role of Hedgehog signaling in postembryonic development and chordate evolution.

    PubMed

    Islam, A F M Tariqul; Moly, Pricila Khan; Miyamoto, Yuki; Kusakabe, Takehiro G

    2010-02-01

    Members of the Hedgehog (Hh) family are soluble ligands that orchestrate a wide spectrum of developmental processes ranging from left-right axis determination of the embryo to tissue patterning and organogenesis. Tunicates, including ascidians, are the closest relatives of vertebrates, and elucidation of Hh signaling in ascidians should provide an important clue towards better understanding the role of this pathway in development. In previous studies, expression patterns of genes encoding Hh and its downstream factor Gli have been examined up to the tailbud stage in the ascidian embryo, but their expression in the larva has not been reported. Here we show the spatial expression patterns of hedgehog (Ci-hh1, Ci-hh2), patched (Ci-ptc), smoothened (Ci-smo), and Gli (Ci-Gli) orthologs in larvae of the ascidian Ciona intestinalis. The expression patterns of Ci-hh2 and Ci-Gli dramatically change during the period between the late tailbud embryo and the swimming larva. At the larval stage, expression of Ci-Gli was found in a central part of the endoderm and in the visceral ganglion, while Ci-hh2 was expressed in two discrete endodermal regions, anteriorly and posteriorly adjacent to the cells expressing Gli. The expression patterns of these genes suggest that the Hh ligand controls postembryonic development of the endoderm and the central nervous system. Expression of a gene encoding Hh in the anterior and/or pharyngeal endoderm is probably an ancient chordate character; diversification of regulation and targets of the Hh signaling in this region may have played a major role in the evolution of chordate body structures.

  11. Reprotoxicity of the Antifoulant Chlorothalonil in Ascidians: An Ecological Risk Assessment

    PubMed Central

    Gallo, Alessandra; Tosti, Elisabetta

    2015-01-01

    Chlorothalonil is a widely used biocide in antifouling paint formulation that replaces tin-based compounds after their definitive ban. Although chlorothalonil inputs into the marine environment have significantly increased in recent years, little is known about its effect on marine animals and in particular on their reproductive processes. In this line, the aim of the present study was to investigate the effects of chlorothalonil exposure on the gamete physiology, fertilization rate and transmissible damage to offspring in the marine invertebrate Ciona intestinalis (ascidians). To identify a possible mechanism of action of chlorothalonil, electrophysiological techniques were used to study the impact on oocyte membrane excitability and on the electrical events occurring at fertilization. The pre-exposure of spermatozoa and oocytes to chlorothalonil did not affect the fertilization rate but caused damage to the offspring by inducing larval malformation. The highest toxicity was observed when fertilization was performed in chlorothalonil solutions with the lowest EC50 value. In particular, it was observed that low chlorothalonil concentrations interfered with embryo development and led to abnormal larvae, whereas high concentrations arrested embryo formation. In mature oocytes, a decrease in the amplitudes of the sodium and fertilization currents was observed, suggesting an involvement of plasma membrane ion currents in the teratogenic mechanism of chlorothalonil action. The risk estimation confirmed that the predicted no-effect concentration (PNEC) exceeded the predicted effect concentration (PEC), thus indicating that chlorothalonil may pose a risk to aquatic species. PMID:25875759

  12. Transmission and Scanning Electron Microscopy of the Accessory Cells and Chorion During Development of Ciona intestinalis Type B Embryos and the Impact of Their Removal on Cell Morphology.

    PubMed

    Thompson, Helen; Shimeld, Sebastian M

    2015-06-01

    Spawned ascidian oocytes are surrounded by a membrane called the chorion (or vitelline coat) and associated with two populations of maternally-supplied cells. Outside the chorion are follicle cells, which may affect the buoyancy of eggs. Inside the chorion are test cells, which during oogenesis provision the egg and which after fertilisation contribute to the larval tunic. The structure of maternal cells may vary between species. The model ascidian Ciona intestinalis has been recently split into two species, currently named type A and type B. The ultrastructure of extraembryonic cells and structures from type A embryos has been reported. Here we describe the ultrastructure of follicle and test cells from C. intestinalis type B embryos. Test cells are about 5 µm in diameter and line the inside of the chorion of developing embryos in a dense sheet. Follicle cells are large (> 100 µm long) and spike-shaped, with many large vesicles. Terminal electron dense granules are found towards the tips of spikes, adjacent to cytoplasm containing numerous small electron dense bodies connected by filaments. These are probably vesicles containing material for the terminal granules. Removal of maternal structures and cells just after fertilisation, as commonly used in many experiments manipulating C. intestinalis development, has been reported to affect embryonic patterning. We examined the impact of this on embryonic ectoderm cells by scanning electron microscopy. Cells of embryos that developed without maternal structures still developed cilia, but had indistinct cell boundaries and a more flattened appearance than those that developed within the chorion.

  13. Asexual propagation and regeneration in colonial ascidians.

    PubMed

    Kürn, Ulrich; Rendulic, Snjezana; Tiozzo, Stefano; Lauzon, Robert J

    2011-08-01

    Regeneration is widely distributed among the metazoans. However, clear differences exist as to the degree of regenerative capacity: some phyla can only replace missing body parts, whereas others can generate entirely new individuals. Ascidians are animals that possess a remarkable regenerative plasticity and exhibit a great diversity of mechanisms for asexual propagation and survival. They are marine invertebrate members of the subphylum Tunicata and represent modern-day descendants of the chordate ancestor; in their tadpole stage they exhibit a chordate body plan that is resorbed during metamorphosis. Solitary species grow into an adult that can reach several centimeters in length, whereas colonial species grow by asexual propagation, creating a colony of genetically identical individuals. In this review, we present an overview of the biology of colonial ascidians as a paradigm for study in stem cell and regenerative biology. Focusing on botryllid ascidians, we introduce the potential roles played by multipotent epithelia and multipotent/pluripotent stem cells as source of asexual propagation and regenerative plasticity in the different budding mechanisms, and consider the putative mechanism of body repatterning in a non-embryonic scenario. We also discuss the involvement of intra-colony homeostatic processes in regulating budding potential, and the functional link between allorecognition, chimerism, and regenerative potential.

  14. Species specificity of symbiosis and secondary metabolism in ascidians

    PubMed Central

    Tianero, Ma Diarey B; Kwan, Jason C; Wyche, Thomas P; Presson, Angela P; Koch, Michael; Barrows, Louis R; Bugni, Tim S; Schmidt, Eric W

    2015-01-01

    Ascidians contain abundant, diverse secondary metabolites, which are thought to serve a defensive role and which have been applied to drug discovery. It is known that bacteria in symbiosis with ascidians produce several of these metabolites, but very little is known about factors governing these ‘chemical symbioses'. To examine this phenomenon across a wide geographical and species scale, we performed bacterial and chemical analyses of 32 different ascidians, mostly from the didemnid family from Florida, Southern California and a broad expanse of the tropical Pacific Ocean. Bacterial diversity analysis showed that ascidian microbiomes are highly diverse, and this diversity does not correlate with geographical location or latitude. Within a subset of species, ascidian microbiomes are also stable over time (R=−0.037, P-value=0.499). Ascidian microbiomes and metabolomes contain species-specific and location-specific components. Location-specific bacteria are found in low abundance in the ascidians and mostly represent strains that are widespread. Location-specific metabolites consist largely of lipids, which may reflect differences in water temperature. By contrast, species-specific bacteria are mostly abundant sequenced components of the microbiomes and include secondary metabolite producers as major components. Species-specific chemicals are dominated by secondary metabolites. Together with previous analyses that focused on single ascidian species or symbiont type, these results reveal fundamental properties of secondary metabolic symbiosis. Different ascidian species have established associations with many different bacterial symbionts, including those known to produce toxic chemicals. This implies a strong selection for this property and the independent origin of secondary metabolite-based associations in different ascidian species. The analysis here streamlines the connection of secondary metabolite to producing bacterium, enabling further biological and

  15. Species specificity of symbiosis and secondary metabolism in ascidians.

    PubMed

    Tianero, Ma Diarey B; Kwan, Jason C; Wyche, Thomas P; Presson, Angela P; Koch, Michael; Barrows, Louis R; Bugni, Tim S; Schmidt, Eric W

    2015-03-01

    Ascidians contain abundant, diverse secondary metabolites, which are thought to serve a defensive role and which have been applied to drug discovery. It is known that bacteria in symbiosis with ascidians produce several of these metabolites, but very little is known about factors governing these 'chemical symbioses'. To examine this phenomenon across a wide geographical and species scale, we performed bacterial and chemical analyses of 32 different ascidians, mostly from the didemnid family from Florida, Southern California and a broad expanse of the tropical Pacific Ocean. Bacterial diversity analysis showed that ascidian microbiomes are highly diverse, and this diversity does not correlate with geographical location or latitude. Within a subset of species, ascidian microbiomes are also stable over time (R=-0.037, P-value=0.499). Ascidian microbiomes and metabolomes contain species-specific and location-specific components. Location-specific bacteria are found in low abundance in the ascidians and mostly represent strains that are widespread. Location-specific metabolites consist largely of lipids, which may reflect differences in water temperature. By contrast, species-specific bacteria are mostly abundant sequenced components of the microbiomes and include secondary metabolite producers as major components. Species-specific chemicals are dominated by secondary metabolites. Together with previous analyses that focused on single ascidian species or symbiont type, these results reveal fundamental properties of secondary metabolic symbiosis. Different ascidian species have established associations with many different bacterial symbionts, including those known to produce toxic chemicals. This implies a strong selection for this property and the independent origin of secondary metabolite-based associations in different ascidian species. The analysis here streamlines the connection of secondary metabolite to producing bacterium, enabling further biological and

  16. Transforming growth factor β (CiTGF-β) gene expression is induced in the inflammatory reaction of Ciona intestinalis.

    PubMed

    Vizzini, Aiti; Di Falco, Felicia; Parrinello, Daniela; Sanfratello, Maria Antonietta; Cammarata, Matteo

    2016-02-01

    Transforming growth factor (TGF-β) is a well-known component of a regulatory cytokines superfamily that has pleiotropic functions in a broad range of cell types and is involved, in vertebrates, in numerous physiological and pathological processes. In the current study, we report on Ciona intestinalis molecular characterisation and expression of a transforming growth factor β homologue (CiTGF-β). The gene organisation, phylogenetic tree and modelling supported the close relationship with the mammalian TGF suggesting that the C. intestinalis TGF-β gene shares a common ancestor in the chordate lineages. Functionally, real-time PCR analysis showed that CiTGF-β was transcriptionally upregulated in the inflammatory process induced by LPS inoculation, suggesting that is involved in the first phase and significant in the secondary phase of the inflammatory response in which cell differentiation occurs. In situ hybridisation assays revealed that the genes transcription was upregulated in the pharynx, the main organ of the ascidian immune system, and expressed by cluster of hemocytes inside the pharynx vessels. These data supported the view that CiTGF-β is a potential molecule in immune defence systems against bacterial infection. PMID:26493014

  17. Ephrin-mediated restriction of ERK1/2 activity delimits the number of pigment cells in the Ciona CNS.

    PubMed

    Haupaix, Nicolas; Abitua, Philip B; Sirour, Cathy; Yasuo, Hitoyoshi; Levine, Michael; Hudson, Clare

    2014-10-01

    Recent evidence suggests that ascidian pigment cells are related to neural crest-derived melanocytes of vertebrates. Using live-imaging, we determine a revised cell lineage of the pigment cells in Ciona intestinalis embryos. The neural precursors undergo successive rounds of anterior-posterior (A-P) oriented cell divisions, starting at the blastula 64-cell stage. A previously unrecognized fourth A-P oriented cell division in the pigment cell lineage leads to the generation of the post-mitotic pigment cell precursors. We provide evidence that MEK/ERK signals are required for pigment cell specification until approximately 30min after the final cell division has taken place. Following each of the four A-P oriented cell divisions, ERK1/2 is differentially activated in the posterior sister cells, into which the pigment cell lineage segregates. Eph/ephrin signals are critical during the third A-P oriented cell division to spatially restrict ERK1/2 activation to the posterior daughter cell. Targeted inhibition of Eph/ephrin signals results in, at neurula stages, anterior expansion of both ERK1/2 activation and a pigment cell lineage marker and subsequently, at larval stages, supernumerary pigment cells. We discuss the implications of these findings with respect to the evolution of the vertebrate neural crest.

  18. Microbial community associated with the colonial ascidian Cystodytes dellechiajei.

    PubMed

    Martínez-García, Manuel; Díaz-Valdés, Marta; Wanner, Gerhard; Ramos-Esplá, Alfonso; Antón, Josefa

    2007-02-01

    The ascidian Cystodytes dellechiajei (Della Valle, 1877) (phylum Chordata, class Ascidiacea, family Polycitoridae) is a colonial tunicate that inhabits benthic rock environments in the Atlantic, Pacific and Indian Oceans, as well as the Mediterranean Sea. Its life cycle has two phases, the adult sessile colony and the free-living larva. Both adult zooids and larvae are surrounded by a protective tunic that contains several eukaryotic cell lines, is composed mainly of acidic mucopolysacharides associated with collagen and elastin-like proteins, and is covered by a thin cuticle. The microbiota associated with the tunic tissues of adult colonies and larva of C. dellechiajei has been examined by optical, confocal and electron microscopy and by fluorescence in situ hybridization (FISH), denaturing gradient gel electrophoresis (DGGE), and 16S rRNA gene clone library analysis. Microscopy analyses indicated the presence inside the tunic, both for the adult and the larva, of a dense community of Bacteria while only the external surface of colony cuticle was colonized by diatoms, rodophyte algae and prokaryotic-like epiphytes. Transmission electron microscopy showed tunic eukaryotic cells that were engulfing and lysing bacteria. 16S rRNA gene analyses (DGGE and clone libraries) and FISH indicated that the community inside the tunic tissues of the adults and larvae was dominated by Alphaproteobacteria. Bacteria belonging to the phyla Gammaproteobacteria and Bacteroidetes were also detected in the adults. Many of the 16S rRNA gene sequences in the tunic tissues were related to known aerobic anoxygenic phototrophs (AAP), like Roseobacter sp. and Erythrobacter sp. In order to check whether the gene pufM, coding for the M subunit of the reaction centre complex of aerobic anoxygenic photosynthesis, was being expressed inside the ascidian tissues, two libraries, one for an adult colony and one for larva, of cDNA from the expressed pufM gene were also constructed. The sequences most

  19. The central nervous system of ascidian larvae.

    PubMed

    Hudson, Clare

    2016-09-01

    Ascidians are marine invertebrate chordates. Their tadpole larvae contain a dorsal tubular nervous system, resulting from the rolling up of a neural plate. Along the anterior-posterior (A-P) axis, the central nervous system (CNS) is organized into a sensory vesicle, neck, trunk ganglion, and tail nerve cord and consists of approximately only 330 cells, of which around 100 are thought to be neurons. The organization of distinct neuronal cell types and neurotransmitter gene expression within the CNS has been described. The unique developmental mode of ascidians, with a small number of cells and a fixed cell division pattern, allows individual cells to be traced throughout development. This feature has led to the complete documentation of the cell lineages of certain cell types in the CNS. Thus, a step-by-step understanding of nervous system development from the initial stages of neural induction to the neurogenesis of individual neurons is a feasible goal. The genetic control of neural fate induction and early neural plate patterning are now well understood. The molecular mechanisms specifying the cholinergic neurons of the trunk ganglion as well as the pigment cells of the sensory organs are also well elucidated. In addition, studies have begun on the morphogenetic processes of neurulation. Remaining challenges include building an embryonic atlas integrating gene expression patterns, cell lineage, and neuronal cell types as well as developing the gene regulatory networks of cell fate specification and integrating them with the genetic control of morphogenesis. WIREs Dev Biol 2016, 5:538-561. doi: 10.1002/wdev.239 For further resources related to this article, please visit the WIREs website. PMID:27328318

  20. Morphological Differences between Larvae of the Ciona intestinalis Species Complex: Hints for a Valid Taxonomic Definition of Distinct Species.

    PubMed

    Pennati, Roberta; Ficetola, Gentile Francesco; Brunetti, Riccardo; Caicci, Federico; Gasparini, Fabio; Griggio, Francesca; Sato, Atsuko; Stach, Thomas; Kaul-Strehlow, Sabrina; Gissi, Carmela; Manni, Lucia

    2015-01-01

    The cosmopolitan ascidian Ciona intestinalis is the most common model species of Tunicata, the sister-group of Vertebrata, and widely used in developmental biology, genomics and evolutionary studies. Recently, molecular studies suggested the presence of cryptic species hidden within the C. intestinalis species, namely C. intestinalis type A and type B. So far, no substantial morphological differences have been identified between individuals belonging to the two types. Here we present morphometric, immunohistochemical, and histological analyses, as well as 3-D reconstructions, of late larvae obtained by cross-fertilization experiments of molecularly determined type A and type B adults, sampled in different seasons and in four different localities. Our data point to quantitative and qualitative differences in the trunk shape of larvae belonging to the two types. In particular, type B larvae exhibit a longer pre-oral lobe, longer and relatively narrower total body length, and a shorter ocellus-tail distance than type A larvae. All these differences were found to be statistically significant in a Discriminant Analysis. Depending on the number of analyzed parameters, the obtained discriminant function was able to correctly classify > 93% of the larvae, with the remaining misclassified larvae attributable to the existence of intra-type seasonal variability. No larval differences were observed at the level of histology and immunohistochemical localization of peripheral sensory neurons. We conclude that type A and type B are two distinct species that can be distinguished on the basis of larval morphology and molecular data. Since the identified larval differences appear to be valid diagnostic characters, we suggest to raise both types to the rank of species and to assign them distinct names.

  1. Centrosomes and spindles in ascidian embryos and eggs.

    PubMed

    McDougall, Alex; Chenevert, Janet; Pruliere, Gerard; Costache, Vlad; Hebras, Celine; Salez, Gregory; Dumollard, Remi

    2015-01-01

    During embryonic development and maternal meiotic maturation, positioning of the mitotic/meiotic spindle is subject to control mechanisms that meet the needs of the particular cell type. Here we review the methods, molecular tools, and the ascidian model we use to study three different ways in which centrosomes or spindles are positioned in three different cellular contexts. First, we review unequal cleavage in the ascidian germ lineage. In the germ cell precursors, a large macromolecular structure termed the centrosome-attracting body causes three successive rounds of unequal cleavage from the 8- to the 64-cell stage. Next, we discuss spindle positioning underlying the invariant cleavage pattern. Ascidian embryos display an invariant cleavage pattern whereby the mitotic spindle aligns in a predetermined orientation in every blastomere up to the gastrula stage (composed of 112 cells). Finally, we review methods and approaches to study meiotic spindle positioning in eggs. PMID:26175446

  2. Toxicity of Hg, Cu, Cd, and Cr on early developmental stages of Ciona intestinalis (Chordata, Ascidiacea) with potential application in marine water quality assessment.

    PubMed

    Bellas, J; Vázquez, E; Beiras, R

    2001-08-01

    The toxicity of mercury, copper, cadmium and chromium on sperm viability, fertilisation, embryogenesis and larval attachment of Ciona intestinalis was examined. Fertilisation rate (FR) showed a small decrease even at the highest metal concentration tested. The median effective concentrations (EC50) reducing rates of embryogenesis and larval attachment by 50% were 54 microg Hg/l (0.27 microM), 46 microg Cu/l (0.72 microM), 838 microg Cd/l (7.46 microM), 10,318 microg Cr/l (198 microM), and 35 microg Hg/l (0.18 microM), 34 microg Cu/l (0.54 microM) and 11,755 microg Cr/l (226 microM), respectively. Therefore, Hg is three times more toxic than Cu (on a molar basis), ca. 30 times more toxic than Cd and ca. 1000 times more toxic than Cr to early stages of C. intestinalis. Rates of larval attachment and embryogenesis were the most sensitive endpoints, although the latter is more advisable for routine assessment of seawater quality because of its greater simplicity. In addition to bivalves and sea-urchins, ascidian embryos can provide biological criteria for seawater quality standards taking into account the sensitivity of a chordate and contributing to the detection of harmful chemicals with no marked effect on the species currently in use in seawater quality bioassays.

  3. LPS injection reprograms the expression and the 3' UTR of a CAP gene by alternative polyadenylation and the formation of a GAIT element in Ciona intestinalis.

    PubMed

    Vizzini, Aiti; Bonura, Angela; Longo, Valeria; Sanfratello, Maria Antonietta; Parrinello, Daniela; Cammarata, Matteo; Colombo, Paolo

    2016-09-01

    The diversification of cellular functions is one of the major characteristics of multicellular organisms which allow cells to modulate their gene expression, leading to the formation of transcripts and proteins with different functions and concentrations in response to different stimuli. CAP genes represent a widespread family of proteins belonging to the cysteine-rich secretory protein, antigen 5 and pathogenesis-related 1 superfamily which, it has been proposed, play key roles in the infection process and the modulation of immune responses in host animals. The ascidian Ciona intestinalis represents a group of proto-chordates with an exclusively innate immune system that has been widely studied in the field of comparative and developmental immunology. Using this biological system, we describe the identification of a novel APA mechanism by which an intronic polyadenylation signal is activated by LPS injection, leading to the formation of a shorter CAP mRNA capable of expressing the first CAP exon plus 19 amino acid residues whose sequence is contained within the first intron of the annotated gene. Furthermore, such an APA event causes the expression of a translational controlling cis-acting GAIT element which is not present in the previously isolated CAP isoform and identified in the 3'-UTR of other immune-related genes, suggesting an intriguing scenario in which both transcriptional and post-transcriptional control mechanisms are involved in the activation of the CAP gene during inflammatory response in C. intestinalis. PMID:27514009

  4. LPS injection reprograms the expression and the 3' UTR of a CAP gene by alternative polyadenylation and the formation of a GAIT element in Ciona intestinalis.

    PubMed

    Vizzini, Aiti; Bonura, Angela; Longo, Valeria; Sanfratello, Maria Antonietta; Parrinello, Daniela; Cammarata, Matteo; Colombo, Paolo

    2016-09-01

    The diversification of cellular functions is one of the major characteristics of multicellular organisms which allow cells to modulate their gene expression, leading to the formation of transcripts and proteins with different functions and concentrations in response to different stimuli. CAP genes represent a widespread family of proteins belonging to the cysteine-rich secretory protein, antigen 5 and pathogenesis-related 1 superfamily which, it has been proposed, play key roles in the infection process and the modulation of immune responses in host animals. The ascidian Ciona intestinalis represents a group of proto-chordates with an exclusively innate immune system that has been widely studied in the field of comparative and developmental immunology. Using this biological system, we describe the identification of a novel APA mechanism by which an intronic polyadenylation signal is activated by LPS injection, leading to the formation of a shorter CAP mRNA capable of expressing the first CAP exon plus 19 amino acid residues whose sequence is contained within the first intron of the annotated gene. Furthermore, such an APA event causes the expression of a translational controlling cis-acting GAIT element which is not present in the previously isolated CAP isoform and identified in the 3'-UTR of other immune-related genes, suggesting an intriguing scenario in which both transcriptional and post-transcriptional control mechanisms are involved in the activation of the CAP gene during inflammatory response in C. intestinalis.

  5. Cross-validated methods for promoter/transcription start site mapping in SL trans-spliced genes, established using the Ciona intestinalis troponin I gene

    PubMed Central

    Khare, Parul; Mortimer, Sandra I.; Cleto, Cynthia L.; Okamura, Kohji; Suzuki, Yutaka; Kusakabe, Takehiro; Nakai, Kenta; Meedel, Thomas H.; Hastings, Kenneth E. M.

    2011-01-01

    In conventionally-expressed eukaryotic genes, transcription start sites (TSSs) can be identified by mapping the mature mRNA 5′-terminal sequence onto the genome. However, this approach is not applicable to genes that undergo pre-mRNA 5′-leader trans-splicing (SL trans-splicing) because the original 5′-segment of the primary transcript is replaced by the spliced leader sequence during the trans-splicing reaction and is discarded. Thus TSS mapping for trans-spliced genes requires different approaches. We describe two such approaches and show that they generate precisely agreeing results for an SL trans-spliced gene encoding the muscle protein troponin I in the ascidian tunicate chordate Ciona intestinalis. One method is based on experimental deletion of trans-splice acceptor sites and the other is based on high-throughput mRNA 5′-RACE sequence analysis of natural RNA populations in order to detect minor transcripts containing the pre-mRNA’s original 5′-end. Both methods identified a single major troponin I TSS located ∼460 nt upstream of the trans-splice acceptor site. Further experimental analysis identified a functionally important TATA element 31 nt upstream of the start site. The two methods employed have complementary strengths and are broadly applicable to mapping promoters/TSSs for trans-spliced genes in tunicates and in trans-splicing organisms from other phyla. PMID:21109525

  6. Evidence of a Native Northwest Atlantic COI Haplotype Clade in the Cryptogenic Colonial Ascidian Botryllus schlosseri.

    PubMed

    Yund, Philip O; Collins, Catherine; Johnson, Sheri L

    2015-06-01

    The colonial ascidian Botryllus schlosseri should be considered cryptogenic (i.e., not definitively classified as either native or introduced) in the Northwest Atlantic. Although all the evidence is quite circumstantial, over the last 15 years most research groups have accepted the scenario of human-mediated dispersal and classified B. schlosseri as introduced; others have continued to consider it native or cryptogenic. We address the invasion status of this species by adding 174 sequences to the growing worldwide database for the mitochondrial gene cytochrome c oxidase subunit I (COI) and analyzing 1077 sequences to compare genetic diversity of one clade of haplotypes in the Northwest Atlantic with two hypothesized source regions (the Northeast Atlantic and Mediterranean). Our results lead us to reject the prevailing view of the directionality of transport across the Atlantic. We argue that the genetic diversity patterns at COI are far more consistent with the existence of at least one haplotype clade in the Northwest Atlantic (and possibly a second) that substantially pre-dates human colonization from Europe, with this native North American clade subsequently introduced to three sites in Northeast Atlantic and Mediterranean waters. However, we agree with past researchers that some sites in the Northwest Atlantic have more recently been invaded by alien haplotypes, so that some populations are currently composed of a mixture of native and invader haplotypes. PMID:26124447

  7. *Arsenic (+3 oxidation state) methyltransferase and the methylation of arsenicals in the invertebrate chordate ciona intestinalis

    EPA Science Inventory

    Biotransformation of inorganic arsenic (iAs) involves methylation catalyzed by arsenic (+3 oxidation state) methyltransferase (As3mt) , yielding mono-, di-, and trimethylated arsenicals. A comparative genomic approach focused on Ciona intestinaJis, an invertebrate chordate, was u...

  8. The secret to a successful relationship: lasting chemistry between ascidians and their symbiotic bacteria

    PubMed Central

    Schmidt, Eric W.

    2014-01-01

    Bioactive secondary metabolites are common components of marine animals. In many cases, symbiotic bacteria, and not the animals themselves, synthesize the compounds. Among marine animals, ascidians are good models for understanding these symbioses. Ascidians often contain potently bioactive secondary metabolites as their major extractable components. Strong evidence shows that ~8% of the known secondary metabolites from ascidians are made by symbiotic bacteria, and indirect evidence implicates bacteria in the synthesis of many more. Far from being “secondary” to the animals, secondary metabolites are essential components of the interaction between host animals and their symbiotic bacteria. These interactions have complex underlying biology, but the chemistry is clearly ascidian-species specific. The chemical interactions are ancient in at least some cases, and they are widespread among ascidians. Ascidians maintain secondary metabolic symbioses with bacteria that are phylogenetically diverse, indicating a convergent solution to obtaining secondary metabolites and reinforcing the importance of secondary metabolism in animal survival. PMID:25937788

  9. Telomerase deficiency in a colonial ascidian after prolonged asexual propagation.

    PubMed

    Sköld, Helen Nilsson; Asplund, Maria E; Wood, Christine A; Bishop, John D D

    2011-06-15

    In organisms that propagate by agametic cloning, the parental body is the reproductive unit and fitness increases with clonal size, so that colonial metazoans, despite lack of experimental data, have been considered potentially immortal. Using asexual propagation rate as a measure of somatic performance, and telomerase activity and relative telomere length as molecular markers of senescence, old (7-12 years) asexual strains of a colonial ascidian, Diplosoma listerianum, were compared with their recent sexually produced progeny. We report for the first time evidence for long-term molecular senescence in asexual lineages of a metazoan, and that only passage between sexual generations provides total rejuvenation permitting indefinite propagation and growth. Thus, this colonial ascidian has not fully escaped ageing. The possibility of somatic replicative senescence also potentially helps to explain why metazoans, with the capacity for asexual propagation through agametic cloning, commonly undergo cycles of sexual reproduction in the wild.

  10. Exploiting the extraordinary genetic polymorphism of ciona for developmental genetics with whole genome sequencing.

    PubMed

    Abdul-Wajid, Sarah; Veeman, Michael T; Chiba, Shota; Turner, Thomas L; Smith, William C

    2014-05-01

    Studies in tunicates such as Ciona have revealed new insights into the evolutionary origins of chordate development. Ciona populations are characterized by high levels of natural genetic variation, between 1 and 5%. This variation has provided abundant material for forward genetic studies. In the current study, we make use of deep sequencing and homozygosity mapping to map spontaneous mutations in outbred populations. With this method we have mapped two spontaneous developmental mutants. In Ciona intestinalis we mapped a short-tail mutation with strong phenotypic similarity to a previously identified mutant in the related species Ciona savignyi. Our bioinformatic approach mapped the mutation to a narrow interval containing a single mutated gene, α-laminin3,4,5, which is the gene previously implicated in C. savignyi. In addition, we mapped a novel genetic mutation disrupting neural tube closure in C. savignyi to a T-type Ca(2+) channel gene. The high efficiency and unprecedented mapping resolution of our study is a powerful advantage for developmental genetics in Ciona, and may find application in other outbred species.

  11. Commensal Leucothoidae (Crustacea, Amphipoda) of the Ryukyu Archipelago, Japan. Part I: ascidian-dwellers

    PubMed Central

    White, Kristine N.; Reimer, James Davis

    2012-01-01

    Abstract Commensal leucothoid amphipods have been collected from the branchial chambers of their ascidian hosts throughout the Ryukyu Archipelago, Japan. Seven new species are described in two genera with valuable location data and host records. An identification key to ascidian-dwelling Leucothoidae of the Ryukyu Archipelago is provided. PMID:22303128

  12. New distributional data on ascidian fauna (Tunicata: Ascidiacea) from Mandapam coast, Gulf of Mannar, India

    PubMed Central

    Akram, Soban A; Arshan, Kaleem ML

    2016-01-01

    Abstract Background Ascidians play a key role in the ecology and biodiversity of marine ecosystem. Ascidians can be transported in ship ballast water and while attached to ship and boat hulls. Heavy traffic by domestic and international ships as well as cargo vessels between the major and minor ports warrants continuous monitoring for new introductions of ascidians. The Mandapam coast is situated in the Gulf of Mannar, India, a marine hot spot area in the Indian Ocean which provides an environment suitable for the settlement of ascidians. New information A total of 30 species of ascidians were reported from Mandapam coastal waters, of which 26 species were new to the study area and five species: Ecteinascidia turbinata, Eudistoma carnosum, Trididemnum caelatum, T. vermiforme and Didemnum spadix, were new to India. PMID:27099557

  13. Sensing charges of the Ciona intestinalis voltage-sensing phosphatase

    PubMed Central

    Frezza, Ludivine; Sandtner, Walter

    2013-01-01

    Voltage control over enzymatic activity in voltage-sensitive phosphatases (VSPs) is conferred by a voltage-sensing domain (VSD) located in the N terminus. These VSDs are constituted by four putative transmembrane segments (S1 to S4) resembling those found in voltage-gated ion channels. The putative fourth segment (S4) of the VSD contains positive residues that likely function as voltage-sensing elements. To study in detail how these residues sense the plasma membrane potential, we have focused on five arginines in the S4 segment of the Ciona intestinalis VSP (Ci-VSP). After implementing a histidine scan, here we show that four arginine-to-histidine mutants, namely R223H to R232H, mediate voltage-dependent proton translocation across the membrane, indicating that these residues transit through the hydrophobic core of Ci-VSP as a function of the membrane potential. These observations indicate that the charges carried by these residues are sensing charges. Furthermore, our results also show that the electrical field in VSPs is focused in a narrow hydrophobic region that separates the extracellular and intracellular space and constitutes the energy barrier for charge crossing. PMID:24127524

  14. Prochloron-ascidian symbioses: Photosynthetic potential and productivity

    NASA Technical Reports Server (NTRS)

    Lewin, R. A.; Cheng, L.; Alberte, R. S.

    1983-01-01

    The chlorophyll content of didemnid asidians with symbiotic algae (Prochloron) from oligotropic tropical marine waters around Palau, Western Carolin Islands is discussed. Several species contain as much chlorophyll per unit dry weight as many herbaceous crop plants and more than do other symbiotic associations such as lichens, green Hydra, etc. Their chlorphyllA/B ratios (3-9) were generally much lighter than those of angiosperms (2-4). Where they abound, Prochloron - ascidian symbiosis could make a major contribution to the productivity, especially in localized areas of tropical marine waters characterized by low nutrient levels and high irradiance.

  15. Photosymbiotic ascidians from Pari Island (Thousand Islands, Indonesia).

    PubMed

    Hirose, Euichi; Iskandar, Budhi Hascaryo; Wardiatno, Yusli

    2014-01-01

    Photosymbiotic ascidian fauna were surveyed in the subtidal zone off Pari Island in the Thousand Islands (Java Sea, Indonesia). Nine species were recorded: Didemnum molle, Trididemnum miniatum, Lissoclinum patella, L. punctatum, L. timorense, Diplosoma gumavirens, D. simile, D. simileguwa, and D. virens. All of these species have been previously recorded in the Ryukyu Archipelago, Japan. Diplosoma gumavirens and D. simileguwa were originally described from the Ryukyu Archipelago in 2009 and 2005, respectively, and all of the observed species are potentially widely distributed in Indo-West Pacific coral reefs. PMID:25061385

  16. Ascidians as excellent models for studying cellular events in the chordate body plan.

    PubMed

    Ogura, Yosuke; Sasakura, Yasunori

    2013-08-01

    The larvae of non-vertebrate chordate ascidians consist of countable numbers of cells. With this feature, ascidians provide us with excellent models for studying cellular events in the construction of the chordate body. This review discusses the recent observations of morphogenetic movements and cell cycles and divisions along with tissue specifications during ascidian embryogenesis. Unequal cleavages take place at the posterior blastomeres during the early cleavage stages of ascidians, and the structure named the centrosome-attracting body restricts the position of the nuclei near the posterior pole to achieve the unequal cleavages. The most-posterior cells differentiate into the primordial germ cells. The gastrulation of ascidians starts as early as the 110-cell stage. During gastrulation, the endodermal cells show two-step changes in cell shape that are crucial for gastrulation. The ascidian notochord is composed of only 40 cells. The 40 cells align to form a single row by an event named the convergent extension, and then the notochord cells undergo vacuolation to transform the notochord into a single hollowed tube. The strictly restricted number of notochord cells is achieved by the regulated number of cell divisions coupled with the differentiation of the cells conducted by a key transcription factor, Brachyury. The dorsally located neural tube is a characteristic of chordates. During the closure of the ascidian neural tube, the epidermis surrounding the neural plate moves toward the midline to close the neural fold. This morphogenetic movement is allowed by an elongation of interphase in the epidermal cell cycles.

  17. Disinfection of fertilized eggs of the edible ascidian Halocynthia roretzi for prevention of soft tunic syndrome.

    PubMed

    Kumagai, Akira; Tanabe, Toru; Nawata, Akatsuki; Suto, Atsushi

    2016-02-25

    Azumiobodo hoyamushi, the causative agent of soft tunic syndrome, was likely introduced to farming sites of the edible ascidian Halocynthia roretzi via ascidian spat. The source of infection is thought to be cysts of A. hoyamushi that reside in the substrates on which the ascidian spat are attached, but not the spat themselves. Thus, there is a need to develop methods to prevent contamination of the substrates with A. hoyamushi during seed production of the ascidian. We evaluated the protozoacidal effects of sodium hypochlorite and povidone-iodine against the flagellate and temporary cyst forms of A. hoyamushi. Additionally, we evaluated the effects of these disinfectants on the development of fertilized ascidian eggs. The flagellate form of A. hoyamushi was completely inactivated by povidone-iodine (5 ppm, 1 min) and sodium hypochlorite (1 ppm, 1 min). The temporary cysts of A. hoyamushi were completely inactivated by both disinfectants (5 ppm, 1 min). Disinfection with 50 ppm povidone-iodine for 15 min or 5 ppm sodium hypochlorite for 15 min had no effect on ascidian embryogenesis. Thus, horizontal transmission of A. hoyamushi via the substrates can be efficiently prevented by disinfecting ascidian eggs or tools used for spawning with povidone-iodine baths ranging from 5 ppm for 1 min to 50 ppm for 15 min without any side effects. PMID:26912045

  18. Autonomy of ascidian fork head/HNF-3 gene expression.

    PubMed

    Shimauchi, Y; Yasuo, H; Satoh, N

    1997-12-01

    We have characterized the expression pattern of a class I fork head/HNF-3 gene (HrHNF3-1) of the ascidian Halocynthia roretzi. Zygotic HrHNF3-1 expression was detectable as early as the 16-cell stage, and the transcript was evident in blastomeres of the endoderm, notochord and mesenchyme lineages of the early embryos. After the late gastrula stage, HrHNF3-1 was also expressed in the presumptive spinal cord cells and some brain cells. The spinal cord of the ascidian tadpole consists of four layers of cells; the dorsal layer, two lateral layers and the ventral layer, the latter of which simply lies on the notochord. Cross-sections of in situ hybridized specimens showed that HrHNF3-1 was expressed in cells of the ventral layer, reminiscent of the floor plate of vertebrate embryos. In addition, we found autonomy in the initiation of early HrHNF3-1 expression, because the gene was expressed in blastomeres continuously dissociated from the first cleavage until the 16-cell stage.

  19. Bioadhesion in ascidians: a developmental and functional genomics perspective

    PubMed Central

    Pennati, Roberta; Rothbächer, Ute

    2015-01-01

    The development of bioadhesives inspired from marine animals is a promising approach to generate new tissue-compatible medical components. A number of marine species, through their adhesive properties, also represent significant foulers that become increasingly problematic to aquaculture, shipping or local biodiversity. In order to develop more sophisticated man-made glues and/or efficient fouling resistant surfaces, it is important to understand the mechanical, structural and molecular properties of adhesive organs in selected species. Ascidians are marine invertebrates with larvae that opportunistically attach to almost any type of submerged surface to undergo metamorphosis into permanently sessile adults. Not only do they represent a globally important fouling organism, but they are becoming increasingly popular as model organisms for developmental biology. The latter is due to their phylogenetic position as the sister group to the vertebrates and their cellular and molecular accessibility for experimentation. In this paper, we review the mechanisms of larval adhesion in ascidians and draw conclusions from comparative analyses of selected species. We further discuss how knowledge from a developmental and functional genomics point of view can advance our understanding of cellular and molecular signatures and their hierarchical usage in animal adhesive organs. PMID:25657840

  20. The Comparative Organismal Approach in Evolutionary Developmental Biology: Insights from Ascidians and Cavefish.

    PubMed

    Jeffery, William R

    2016-01-01

    Important contributions to evolutionary developmental biology have been made using the comparative organismal approach. As examples, I describe insights obtained from studies of Molgula ascidians and Astyanax cavefish. PMID:26970636

  1. The Whereabouts of an Ancient Wanderer: Global Phylogeography of the Solitary Ascidian Styela plicata

    PubMed Central

    Pineda, Mari Carmen; López-Legentil, Susanna; Turon, Xavier

    2011-01-01

    Genetic tools have greatly aided in tracing the sources and colonization history of introduced species. However, recurrent introductions and repeated shuffling of populations may have blurred some of the genetic signals left by ancient introductions. Styela plicata is a solitary ascidian distributed worldwide. Although its origin remains unclear, this species is believed to have spread worldwide by travelling on ship's hulls. The goals of this study were to infer the genetic structure and global phylogeography of S. plicata and to look for present-day and historical genetic patterns. Two genetic markers were used: a fragment of the mitochondrial gene Cytochrome Oxidase subunit I (COI) and a fragment of the nuclear gene Adenine Nucleotide Transporter/ADP-ATP Translocase (ANT). A total of 368 individuals for COI and 315 for ANT were sequenced from 17 locations worldwide. The levels of gene diversity were moderate for COI to high for ANT. The Mediterranean populations showed the least diversity and allelic richness for both markers, while the Indian, Atlantic and Pacific Oceans had the highest gene and nucleotide diversities. Network and phylogenetic analyses with COI and ANT revealed two groups of alleles separated by 15 and 4 mutational steps, respectively. The existence of different lineages suggested an ancient population split. However, the geographic distributions of these groups did not show any consistent pattern, indicating different phylogeographic histories for each gene. Genetic divergence was significant for many population-pairs irrespective of the geographic distance among them. Stochastic introduction events are reflected in the uneven distribution of COI and ANT allele frequencies and groups among many populations. Our results confirmed that S. plicata has been present in all studied oceans for a long time, and that recurrent colonization events and occasional shuffling among populations have determined the actual genetic structure of this species

  2. Ascidian depth zonation on sublittoral hard substrates off deer island, New Brunswick, Canada

    NASA Astrophysics Data System (ADS)

    Hatfield, C.; Logan, A.; Thomas, M. L. H.

    1992-02-01

    The upper surfaces of sublittoral hard substrates in the Deer Island region of the Bay of Fundy, New Brunswick, support diverse, depth-zoned epibenthic communities of which ascidians form a minor part. Their population density was quantitatively studied from photo-transects taken between mean low water (MLW) and 30 m depth at four sites off the Deer Island coast and from 30-140 m depth along two photo-transects in Head Harbour Passage. All photo-analyses were aided by collections from transect survey sites, wharf pilings and salmon cage floats, to yield a total of 15 ascidian species encountered. Ascidians were found at all depths at the four shallow sites. Halocynthia pyriformis and Boltenia ovifera are most common at depths of less than 20 m, while Aplidium pallidum, Didemnum albidum and other species exhibit a marked increase in abundance below this depth. Cluster analysis of ascidians shows an association between B. echinata and B. ovifera, which may reflect resource partitioning, and between A. pallidum-D. albidum and Molgula sp.— A. stellatum, the ecological significance of which are as yet unknown. The community in Head Harbour Passage is animal-dominated and in its deeper sections often shows three-dimensional bottom relief from horse mussel shells. D. albidum, the commonest ascidian, shows a close association with Modiolus modiolus, to which it is normally attached, suggesting that mussel beds may minimize the possibility of dislodgement and even confer a feeding advantage on this ascidian.

  3. The challenges of trafficking hydrolysis prone metals and ascidians as an archetype.

    PubMed

    Gaffney, Jean P; Valentine, Ann M

    2011-06-14

    Some of the metal ions that are required, exploited, or simply managed in biological systems are susceptible to hydrolysis and to hydrolytic precipitation in the aqueous, aerobic environment of much of biology. Organisms have evolved exquisite mechanisms for handling these metal ions, offering striking examples of biological control over inorganic coordination chemistry. This year marks the one hundredth anniversary of the discovery of remarkably high vanadium concentrations in the blood cells of the ascidian. In the ensuing years, these marine invertebrates were established as masters of the biological chemistry of very hydrolysis-prone metals, with various ascidian species accumulating high concentrations of iron, vanadium, and titanium, among others. These three metals have very different histories of biological relevance, and many questions remain about how, and ultimately why, these organisms sequester them. This Perspective addresses the aqueous coordination chemistry that organisms like ascidians must control if they are to manipulate hydrolysis-prone metal ions, and describes some of the ascidian biomolecules that have been implicated in this phenomenon. The recently available genome sequence for one ascidian species offers a glimpse into its metal-management arsenal. It offers the opportunity to map the relatively well-studied paradigm of iron management onto the genome of an organism that is intermediate in evolution between invertebrates and vertebrates. The ascidians have much to teach us about how to manage metals like iron, titanium, and vanadium and how that ability evolved.

  4. Phallusiasterol C, A New Disulfated Steroid from the Mediterranean Tunicate Phallusia fumigata.

    PubMed

    Imperatore, Concetta; Senese, Maria; Aiello, Anna; Luciano, Paolo; Fiorucci, Stefano; D'Amore, Claudio; Carino, Adriana; Menna, Marialuisa

    2016-01-01

    A new sulfated sterol, phallusiasterol C (1), has been isolated from the Mediterranean ascidian Phallusia fumigata and its structure has been determined on the basis of extensive spectroscopic (mainly 2D NMR) analysis. The possible role in regulating the pregnane X receptor (PXR) activity of phallusiasterol C has been investigated; although the new sterol resulted inactive, this study adds more items to the knowledge of the structure-PXR regulating activity relationships in the case of sulfated steroids. PMID:27322293

  5. Phallusiasterol C, A New Disulfated Steroid from the Mediterranean Tunicate Phallusia fumigata

    PubMed Central

    Imperatore, Concetta; Senese, Maria; Aiello, Anna; Luciano, Paolo; Fiorucci, Stefano; D’Amore, Claudio; Carino, Adriana; Menna, Marialuisa

    2016-01-01

    A new sulfated sterol, phallusiasterol C (1), has been isolated from the Mediterranean ascidian Phallusia fumigata and its structure has been determined on the basis of extensive spectroscopic (mainly 2D NMR) analysis. The possible role in regulating the pregnane X receptor (PXR) activity of phallusiasterol C has been investigated; although the new sterol resulted inactive, this study adds more items to the knowledge of the structure-PXR regulating activity relationships in the case of sulfated steroids. PMID:27322293

  6. Phallusiasterol C, A New Disulfated Steroid from the Mediterranean Tunicate Phallusia fumigata.

    PubMed

    Imperatore, Concetta; Senese, Maria; Aiello, Anna; Luciano, Paolo; Fiorucci, Stefano; D'Amore, Claudio; Carino, Adriana; Menna, Marialuisa

    2016-01-01

    A new sulfated sterol, phallusiasterol C (1), has been isolated from the Mediterranean ascidian Phallusia fumigata and its structure has been determined on the basis of extensive spectroscopic (mainly 2D NMR) analysis. The possible role in regulating the pregnane X receptor (PXR) activity of phallusiasterol C has been investigated; although the new sterol resulted inactive, this study adds more items to the knowledge of the structure-PXR regulating activity relationships in the case of sulfated steroids.

  7. Contrasting global genetic patterns in two biologically similar, widespread and invasive Ciona species (Tunicata, Ascidiacea)

    PubMed Central

    Bouchemousse, Sarah; Bishop, John D. D.; Viard, Frédérique

    2016-01-01

    Human-mediated dispersal interplays with natural processes and complicates understanding of the biogeographical history of species. This is exemplified by two invasive tunicates, Ciona robusta (formerly Ciona intestinalis type A) and C. intestinalis (formerly Ciona intestinalis type B), globally distributed and sympatric in Europe. By gathering new mitochondrial sequences that were merged with published datasets, we analysed genetic patterns in different regions, with a focus on 1) their sympatric range and 2) allopatric populations in N and S America and southern Europe. In the sympatric range, the two species display contrasting genetic diversity patterns, with low polymorphism in C. robusta supporting the prevalent view of its recent introduction. In the E Pacific, several genetic traits support the non-native status of C. robusta. However, in the NE Pacific, this appraisal requires a complex scenario of introduction and should be further examined supported by extensive sampling efforts in the NW Pacific (putative native range). For C. intestinalis, Bayesian analysis suggested a natural amphi-North Atlantic distribution, casting doubt on its non-native status in the NW Atlantic. This study shows that both natural and human-mediated dispersal have influenced genetic patterns at broad scales; this interaction lessens our ability to confidently ascertain native vs. non-native status of populations, particularly of those species that are globally distributed. PMID:27137892

  8. Sunlight Damage To The Solitary Ascidian Chelyosoma productum

    NASA Astrophysics Data System (ADS)

    Flores, E.

    2004-12-01

    Chelyosoma productum (Stimpson) is a temperate solitary ascidian commonly found in Puget Sound and the San Juan Archipelago, Washington, USA. Adult populations are restricted to deeper subtidal regions or shaded shallow-water habitats, such as docks in shaded marinas. C. productum adults have a thin translucent outer tunic that may provide very little if any protection from solar damage. I hypothesized that sunlight may be setting limits on the distribution of this species. Since adult ascidians are sessile and rely on earlier life stages for their distribution, all life stages of Chelyosoma productum were tested. In this study, I examined the effects of sunlight exposure in embryos, larvae, juveniles and adults of Chelyosoma productum. I isolated the PAR, UVA and UVB portions of the spectrum and exposed all life stages using natural sunlight. I also sampled shallow-water dock habitats to see how adult distributions were related to light exposure. The embryonic development in C. productum was negatively affected by any solar exposure. Most embryos exposed to UV light failed to develop normally and those that did could not subsequently settle. This species produces embryos of different colors; two (purple and brown) were observed in my experiments. Damage from light exposure differed between the color morphs. Overall, the brown morph was more tolerant of light exposure than was the purple morph across all life stages. The only exception to this general pattern was that purple embryos were remarkably resistant to light damage. The distribution of C. productum is restricted to areas with no direct solar exposure. However, even within shaded environments where they were abundant, subpopulations related to the color dimorphism were observed. The significance of the brown and purple pigments in embryos and larvae remains largely unknown. However, adults with brown eggs were found to be more prevalent in edge environments where there was higher light exposure. Purple

  9. Sexual and asexual reproduction in the colonial ascidian Botryllus schlosseri.

    PubMed

    Gasparini, Fabio; Manni, Lucia; Cima, Francesca; Zaniolo, Giovanna; Burighel, Paolo; Caicci, Federico; Franchi, Nicola; Schiavon, Filippo; Rigon, Francesca; Campagna, Davide; Ballarin, Loriano

    2015-01-01

    The colonial tunicate Botryllus schlosseri is a widespread filter-feeding ascidian that lives in shallow waters and is easily reared in aquaria. Its peculiar blastogenetic cycle, characterized by the presence of three blastogenetic generations (filtering adults, buds, and budlets) and by recurrent generation changes, has resulted in over 60 years of studies aimed at understanding how sexual and asexual reproduction are coordinated and regulated in the colony. The possibility of using different methodological approaches, from classical genetics to cell transplantation, contributed to the development of this species as a valuable model organism for the study of a variety of biological processes. Here, we review the main studies detailing rearing, staging methods, reproduction and colony growth of this species, emphasizing the asymmetry in sexual and asexual reproduction potential, sexual reproduction in the field and the laboratory, and self- and cross-fertilization. These data, opportunely matched with recent tanscriptomic and genomic outcomes, can give a valuable help to the elucidation of some important steps in chordate evolution.

  10. Down under the tunic: bacterial biodiversity hotspots and widespread ammonia-oxidizing archaea in coral reef ascidians.

    PubMed

    Erwin, Patrick M; Pineda, Mari Carmen; Webster, Nicole; Turon, Xavier; López-Legentil, Susanna

    2014-03-01

    Ascidians are ecologically important components of marine ecosystems yet the ascidian microbiota remains largely unexplored beyond a few model species. We used 16S rRNA gene tag pyrosequencing to provide a comprehensive characterization of microbial symbionts in the tunic of 42 Great Barrier Reef ascidian samples representing 25 species. Results revealed high bacterial biodiversity (3 217 unique operational taxonomic units (OTU0.03) from 19 described and 14 candidate phyla) and the widespread occurrence of ammonia-oxidizing Thaumarchaeota in coral reef ascidians (24 of 25 host species). The ascidian microbiota was clearly differentiated from seawater microbial communities and included symbiont lineages shared with other invertebrate hosts as well as unique, ascidian-specific phylotypes. Several rare seawater microbes were markedly enriched (200-700 fold) in the ascidian tunic, suggesting that the rare biosphere of seawater may act as a conduit for horizontal symbiont transfer. However, most OTUs (71%) were rare and specific to single hosts and a significant correlation between host relatedness and symbiont community similarity was detected, indicating a high degree of host-specificity and potential role of vertical transmission in structuring these communities. We hypothesize that the complex ascidian microbiota revealed herein is maintained by the dynamic microenvironments within the ascidian tunic, offering optimal conditions for different metabolic pathways such as ample chemical substrate (ammonia-rich host waste) and physical habitat (high oxygen, low irradiance) for nitrification. Thus, ascidian hosts provide unique and fertile niches for diverse microorganisms and may represent an important and previously unrecognized habitat for nitrite/nitrate regeneration in coral reef ecosystems.

  11. Genetic pathways for differentiation of the peripheral nervous system in ascidians.

    PubMed

    Waki, Kana; Imai, Kaoru S; Satou, Yutaka

    2015-01-01

    Ascidians belong to tunicates, the sister group of vertebrates. Peripheral nervous systems (PNSs) including epidermal sensory neurons (ESNs) in the trunk and dorsal tail regions of ascidian larvae are derived from cells adjacent to the neural plate, as in vertebrates. On the other hand, peripheral ESNs in the ventral tail region are derived from the ventral ectoderm under the control of BMP signalling, reminiscent of sensory neurons of amphioxus and protostomes. In this study, we show that two distinct mechanisms activate a common gene circuit consisting of Msx, Ascl.b, Tox, Delta.b and Pou4 in the dorsal and ventral regions to differentiate ESNs. Our results suggest that ventral ESNs of the ascidian larva are not directly homologous to vertebrate PNSs. The dorsal ESNs might have arisen via co-option of the original PNS gene circuit to the neural plate border in an ancestral chordate. PMID:26515371

  12. Ascidians as excellent chordate models for studying the development of the nervous system during embryogenesis and metamorphosis.

    PubMed

    Sasakura, Yasunori; Mita, Kaoru; Ogura, Yosuke; Horie, Takeo

    2012-04-01

    The swimming larvae of the chordate ascidians possess a dorsal hollowed central nervous system (CNS), which is homologous to that of vertebrates. Despite the homology, the ascidian CNS consists of a countable number of cells. The simple nervous system of ascidians provides an excellent experimental system to study the developmental mechanisms of the chordate nervous system. The neural fate of the cells consisting of the ascidian CNS is determined in both autonomous and non-autonomous fashion during the cleavage stage. The ascidian neural plate performs the morphogenetic movement of neural tube closure that resembles that in vertebrate neural tube formation. Following neurulation, the CNS is separated into five distinct regions, whose homology with the regions of vertebrate CNS has been discussed. Following their larval stage, ascidians undergo a metamorphosis and become sessile adults. The metamorphosis is completed quickly, and therefore the metamorphosis of ascidians is a good experimental system to observe the reorganization of the CNS during metamorphosis. A recent study has shown that the major parts of the larval CNS remain after the metamorphosis to form the adult CNS. In contrast to such a conserved manner of CNS reorganization, most larval neurons disappear during metamorphosis. The larval glial cells in the CNS are the major source for the formation of the adult CNS, and some of the glial cells produce adult neurons.

  13. Dissection of a Ciona regulatory element reveals complexity of cross-species enhancer activity.

    PubMed

    Chen, Wei-Chung; Pauls, Stefan; Bacha, Jamil; Elgar, Greg; Loose, Matthew; Shimeld, Sebastian M

    2014-06-15

    Vertebrate genomes share numerous conserved non-coding elements, many of which function as enhancer elements and are hypothesised to be under evolutionary constraint due to a need to be bound by combinations of sequence-specific transcription factors. In contrast, few such conserved elements can be detected between vertebrates and their closest invertebrate relatives. Despite this lack of sequence identity, cross-species transgenesis has identified some cases where non-coding DNA from invertebrates drives reporter gene expression in transgenic vertebrates in patterns reminiscent of the expression of vertebrate orthologues. Such instances are presumed to reflect the presence of conserved suites of binding sites in the regulatory regions of invertebrate and vertebrate orthologues, such that both regulatory elements can correctly interpret the trans-activating environment. Shuffling of binding sites has been suggested to lie behind loss of sequence conservation; however this has not been experimentally tested. Here we examine the underlying basis of enhancer activity for the Ciona intestinalis βγ-crystallin gene, which drives expression in the lens of transgenic vertebrates despite the Ciona lineage predating the evolution of the lens. We construct an interactive gene regulatory network (GRN) for vertebrate lens development, allowing network interactions to be robustly catalogued and conserved network components and features to be identified. We show that a small number of binding motifs are necessary for Ciona βγ-crystallin expression, and narrow down the likely factors that bind to these motifs. Several of these overlap with the conserved core of the vertebrate lens GRN, implicating these sites in cross species function. However when we test these motifs in a transgenic vertebrate they prove to be dispensable for reporter expression in the lens. These results show that current models depicting cross species enhancer function as dependent on conserved binding

  14. Ascidian (Chordata-Tunicata) glycosaminoglycans: extraction, purification, biochemical, and spectroscopic analysis.

    PubMed

    Pavão, Mauro S G

    2015-01-01

    Sulfated polysaccharides with unique structures of the chondroitin/dermatan and heparin/heparan families of sulfated glycosaminoglycans have been described in several species of ascidians (Chordata-Tunicata). These unique sulfated glycans have been isolated from-ascidians and characterized by biochemical and spectroscopic methods. The ascidian glycans can be extracted by different tissues or cells by proteolytic digestion followed by cetylpyridinium chloride/ethanol precipitation. The total glycans are then fractionated by ion-exchange chromatography on DEAE-cellulose and/or Mono Q (HR 5/5) columns. Alternatively, precipitation with different ethanol concentrations can be employed. An initial analysis of the purified ascidian glycans is carried out by agarose gel electrophoresis on diaminopropane/acetate buffer, before or after digestion with specific glycosaminoglycan lyases or deaminative cleavage with nitrous acid. The disaccharides formed by exhaustive degradation of the glycans is purified by gel-filtration chromatography on a Superdex-peptide column and analyzed by HPLC on a strong ion exchange Sax-Spherisorb column. 1H or 13C nuclear magnetic resonance spectroscopy in one or two dimensions is used to confirm the structure of the intact glycans.

  15. Natural Products from Antarctic Colonial Ascidians of the Genera Aplidium and Synoicum: Variability and Defensive Role

    PubMed Central

    Núñez-Pons, Laura; Carbone, Marianna; Vázquez, Jennifer; Rodríguez, Jaime; Nieto, Rosa María; Varela, María Mercedes; Gavagnin, Margherita; Avila, Conxita

    2012-01-01

    Ascidians have developed multiple defensive strategies mostly related to physical, nutritional or chemical properties of the tunic. One of such is chemical defense based on secondary metabolites. We analyzed a series of colonial Antarctic ascidians from deep-water collections belonging to the genera Aplidium and Synoicum to evaluate the incidence of organic deterrents and their variability. The ether fractions from 15 samples including specimens of the species A. falklandicum, A. fuegiense, A. meridianum, A. millari and S. adareanum were subjected to feeding assays towards two relevant sympatric predators: the starfish Odontaster validus, and the amphipod Cheirimedon femoratus. All samples revealed repellency. Nonetheless, some colonies concentrated defensive chemicals in internal body-regions rather than in the tunic. Four ascidian-derived meroterpenoids, rossinones B and the three derivatives 2,3-epoxy-rossinone B, 3-epi-rossinone B, 5,6-epoxy-rossinone B, and the indole alkaloids meridianins A–G, along with other minoritary meridianin compounds were isolated from several samples. Some purified metabolites were tested in feeding assays exhibiting potent unpalatabilities, thus revealing their role in predation avoidance. Ascidian extracts and purified compound-fractions were further assessed in antibacterial tests against a marine Antarctic bacterium. Only the meridianins showed inhibition activity, demonstrating a multifunctional defensive role. According to their occurrence in nature and within our colonial specimens, the possible origin of both types of metabolites is discussed. PMID:23015772

  16. Microenvironment and phylogenetic diversity of Prochloron inhabiting the surface of crustose didemnid ascidians.

    PubMed

    Nielsen, Daniel A; Pernice, Mathieu; Schliep, Martin; Sablok, Gaurav; Jeffries, Thomas C; Kühl, Michael; Wangpraseurt, Daniel; Ralph, Peter J; Larkum, Anthony W D

    2015-10-01

    The cyanobacterium Prochloron didemni is primarily found in symbiotic relationships with various marine hosts such as ascidians and sponges. Prochloron remains to be successfully cultivated outside of its host, which reflects a lack of knowledge of its unique ecophysiological requirements. We investigated the microenvironment and diversity of Prochloron inhabiting the upper, exposed surface of didemnid ascidians, providing the first insights into this microhabitat. The pH and O2 concentration in this Prochloron biofilm changes dynamically with irradiance, where photosynthetic activity measurements showed low light adaptation (Ek ∼ 80 ± 7 μmol photons m(-2) s(-1)) but high light tolerance. Surface Prochloron cells exhibited a different fine structure to Prochloron cells from cloacal cavities in other ascidians, the principle difference being a central area of many vacuoles dissected by single thylakoids in the surface Prochloron. Cyanobacterial 16S rDNA pyro-sequencing of the biofilm community on four ascidians resulted in 433 operational taxonomic units (OTUs) where on average -85% (65-99%) of all sequence reads, represented by 136 OTUs, were identified as Prochloron via blast search. All of the major Prochloron-OTUs clustered into independent, highly supported phylotypes separate from sequences reported for internal Prochloron, suggesting a hitherto unexplored genetic variability among Prochloron colonizing the outer surface of didemnids. PMID:26176189

  17. THE EFFECT OF EXPOSURE PERIOD AND TEMPERATURE ON THE PHOTOSENSORY PROCESS IN CIONA.

    PubMed

    Hecht, S

    1926-01-01

    1. Experiments are presented which show that the latent period in the photosensory response of Ciona is inversely proportional to the duration of the exposure period to light. From this it is found that the velocity of the chemical reaction which determines the latent period is directly proportional to the concentration of photochemical products formed during the exposure period. This is interpreted as showing that the two processes form a coupled photochemical reaction, of which the secondary reaction proceeds only in the presence of products from the primary reaction. This coupling may be a catalysis or a direct chemical relation. 2. Further experiments show that the relation between temperature and the latent period is accurately described by the Arrhenius equation in which micro = 16,200. The precise numerical value of micro tentatively identifies the latent period process as an oxidation reaction which is catalyzed by iron. 3. The photocatalytic properties of certain iron compounds are used as a model for the coupled photochemical reaction suggested for the photosensory mechanism of Ciona and Mya.

  18. Matrix adhesion polarizes heart progenitor induction in the invertebrate chordate Ciona intestinalis.

    PubMed

    Norton, Jennifer; Cooley, James; Islam, A F M Tariqul; Cota, Christina D; Davidson, Brad

    2013-03-01

    Cell-matrix adhesion strongly influences developmental signaling. Resulting impacts on cell migration and tissue morphogenesis are well characterized. However, the in vivo impact of adhesion on fate induction remains ambiguous. Here, we employ the invertebrate chordate Ciona intestinalis to delineate an essential in vivo role for matrix adhesion in heart progenitor induction. In Ciona pre-cardiac founder cells, invasion of the underlying epidermis promotes localized induction of the heart progenitor lineage. We found that these epidermal invasions are associated with matrix adhesion along the pre-cardiac cell/epidermal boundary. Through targeted manipulations of RAP GTPase activity, we were able to manipulate pre-cardiac cell-matrix adhesion. Targeted disruption of pre-cardiac cell-matrix adhesion blocked heart progenitor induction. Conversely, increased matrix adhesion generated expanded induction. We were also able to selectively restore cell-matrix adhesion and heart progenitor induction through targeted expression of Ci-Integrin β2. These results indicate that matrix adhesion functions as a necessary and sufficient extrinsic cue for regional heart progenitor induction. Furthermore, time-lapse imaging suggests that cytokinesis acts as an intrinsic temporal regulator of heart progenitor adhesion and induction. Our findings highlight a potentially conserved role for matrix adhesion in early steps of vertebrate heart progenitor specification.

  19. Immune competence of the Ciona intestinalis pharynx: complement system-mediated activity.

    PubMed

    Giacomelli, Stefano; Melillo, Daniela; Lambris, John D; Pinto, Maria Rosaria

    2012-10-01

    In the tunicate Ciona intestinalis, the ciliated pharynx, which connects the external environment to a highly developed and compartmentalized gastrointestinal system, represents the natural portal of entry for a vast and diverse, potentially pathogenic microbial community. To address the role of the pharynx in immune surveillance in Ciona, we asked whether C3, the key component of the complement system, was expressed in this organ and whether the encoded protein was functionally active. We found by real-time PCR that C3, constitutively expressed in the pharynx, is up-regulated by LPS injection. Using two specific anti-CiC3 and anti-CiC3a polyclonal antibodies in immunohistochemical staining of pharynx sections, we found that the gene product was localized to hemocytes of the pharyngeal bars (identified as granular amoebocytes) and in stigmata ciliated cells. Use of the same antibodies in Western blot analysis indicated that CiC3 and its activation products CiC3b and CiC3a are present in pharynx homogenates. Our observation that the amount of the bioactive fragment CiC3a increased in the pharynx of LPS-treated animals provides the first molecular and functional evidence for complement-mediated immunological activity in the tunicate pharynx.

  20. Stochasticity in space, persistence in time: genetic heterogeneity in harbour populations of the introduced ascidian Styela plicata

    PubMed Central

    Pineda, Mari-Carmen; Lorente, Beatriz; López-Legentil, Susanna; Palacín, Creu

    2016-01-01

    Spatio-temporal changes in genetic structure among populations provide crucial information on the dynamics of secondary spread for introduced marine species. However, temporal components have rarely been taken into consideration when studying the population genetics of non-indigenous species. This study analysed the genetic structure of Styela plicata, a solitary ascidian introduced in harbours and marinas of tropical and temperate waters, across spatial and temporal scales. A fragment of the mitochondrial gene Cytochrome Oxidase subunit I (COI) was sequenced from 395 individuals collected at 9 harbours along the NW Mediterranean coast and adjacent Atlantic waters (> 1,200 km range) at two time points 5 years apart (2009 and 2014). The levels of gene diversity were relatively low for all 9 locations in both years. Analyses of genetic differentiation and distribution of molecular variance revealed strong genetic structure, with significant differences among many populations, but no significant differences among years. A weak and marginally significant correlation between geographic distance and gene differentiation was found. Our results revealed spatial structure and temporal genetic homogeneity in S. plicata, suggesting a limited role of recurrent, vessel-mediated transport of organisms among small to medium-size harbours. Our study area is representative of many highly urbanized coasts with dense harbours. In these environments, the episodic chance arrival of colonisers appears to determine the genetic structure of harbour populations and the genetic composition of these early colonising individuals persists in the respective harbours, at least over moderate time frames (five years) that encompass ca. 20 generations of S. plicata. PMID:27366653

  1. Stochasticity in space, persistence in time: genetic heterogeneity in harbour populations of the introduced ascidian Styela plicata.

    PubMed

    Pineda, Mari-Carmen; Lorente, Beatriz; López-Legentil, Susanna; Palacín, Creu; Turon, Xavier

    2016-01-01

    Spatio-temporal changes in genetic structure among populations provide crucial information on the dynamics of secondary spread for introduced marine species. However, temporal components have rarely been taken into consideration when studying the population genetics of non-indigenous species. This study analysed the genetic structure of Styela plicata, a solitary ascidian introduced in harbours and marinas of tropical and temperate waters, across spatial and temporal scales. A fragment of the mitochondrial gene Cytochrome Oxidase subunit I (COI) was sequenced from 395 individuals collected at 9 harbours along the NW Mediterranean coast and adjacent Atlantic waters (> 1,200 km range) at two time points 5 years apart (2009 and 2014). The levels of gene diversity were relatively low for all 9 locations in both years. Analyses of genetic differentiation and distribution of molecular variance revealed strong genetic structure, with significant differences among many populations, but no significant differences among years. A weak and marginally significant correlation between geographic distance and gene differentiation was found. Our results revealed spatial structure and temporal genetic homogeneity in S. plicata, suggesting a limited role of recurrent, vessel-mediated transport of organisms among small to medium-size harbours. Our study area is representative of many highly urbanized coasts with dense harbours. In these environments, the episodic chance arrival of colonisers appears to determine the genetic structure of harbour populations and the genetic composition of these early colonising individuals persists in the respective harbours, at least over moderate time frames (five years) that encompass ca. 20 generations of S. plicata. PMID:27366653

  2. Endozoicomonas Are Specific, Facultative Symbionts of Sea Squirts.

    PubMed

    Schreiber, Lars; Kjeldsen, Kasper U; Funch, Peter; Jensen, Jeppe; Obst, Matthias; López-Legentil, Susanna; Schramm, Andreas

    2016-01-01

    Ascidians are marine filter feeders and harbor diverse microbiota that can exhibit a high degree of host-specificity. Pharyngeal samples of Scandinavian and Mediterranean ascidians were screened for consistently associated bacteria by culture-dependent and -independent approaches. Representatives of the Endozoicomonas (Gammaproteobacteria, Hahellaceae) clade were detected in the ascidian species Ascidiella aspersa, Ascidiella scabra, Botryllus schlosseri, Ciona intestinalis, Styela clava, and multiple Ascidia/Ascidiella spp. In total, Endozoicomonas was detected in more than half of all specimens screened, and in 25-100% of the specimens for each species. The retrieved Endozoicomonas 16S rRNA gene sequences formed an ascidian-specific subclade, whose members were detected by fluorescence in situ hybridization (FISH) as extracellular microcolonies in the pharynx. Two strains of the ascidian-specific Endozoicomonas subclade were isolated in pure culture and characterized. Both strains are chemoorganoheterotrophs and grow on mucin (a mucus glycoprotein). The strains tested negative for cytotoxic or antibacterial activity. Based on these observations, we propose ascidian-associated Endozoicomonas to be commensals, living off the mucus continuously secreted into the pharynx. Members of the ascidian-specific Endozoicomonas subclade were also detected in seawater from the Scandinavian sampling site, which suggests acquisition of the symbionts by horizontal transmission. The combined results indicate a host-specific, yet facultative symbiosis between ascidians and Endozoicomonas. PMID:27462299

  3. Endozoicomonas Are Specific, Facultative Symbionts of Sea Squirts

    PubMed Central

    Schreiber, Lars; Kjeldsen, Kasper U.; Funch, Peter; Jensen, Jeppe; Obst, Matthias; López-Legentil, Susanna; Schramm, Andreas

    2016-01-01

    Ascidians are marine filter feeders and harbor diverse microbiota that can exhibit a high degree of host-specificity. Pharyngeal samples of Scandinavian and Mediterranean ascidians were screened for consistently associated bacteria by culture-dependent and -independent approaches. Representatives of the Endozoicomonas (Gammaproteobacteria, Hahellaceae) clade were detected in the ascidian species Ascidiella aspersa, Ascidiella scabra, Botryllus schlosseri, Ciona intestinalis, Styela clava, and multiple Ascidia/Ascidiella spp. In total, Endozoicomonas was detected in more than half of all specimens screened, and in 25–100% of the specimens for each species. The retrieved Endozoicomonas 16S rRNA gene sequences formed an ascidian-specific subclade, whose members were detected by fluorescence in situ hybridization (FISH) as extracellular microcolonies in the pharynx. Two strains of the ascidian-specific Endozoicomonas subclade were isolated in pure culture and characterized. Both strains are chemoorganoheterotrophs and grow on mucin (a mucus glycoprotein). The strains tested negative for cytotoxic or antibacterial activity. Based on these observations, we propose ascidian-associated Endozoicomonas to be commensals, living off the mucus continuously secreted into the pharynx. Members of the ascidian-specific Endozoicomonas subclade were also detected in seawater from the Scandinavian sampling site, which suggests acquisition of the symbionts by horizontal transmission. The combined results indicate a host-specific, yet facultative symbiosis between ascidians and Endozoicomonas. PMID:27462299

  4. Mediterranean diet

    MedlinePlus

    ... doctor if you should take a calcium supplement. Wine is a common part of a Mediterranean eating ... but some people should not drink alcohol. Avoid wine if you are prone to alcohol abuse, pregnant, ...

  5. Dynamics of cell polarity in tissue morphogenesis: a comparative view from Drosophila and Ciona.

    PubMed

    Veeman, Michael T; McDonald, Jocelyn A

    2016-01-01

    Tissues in developing embryos exhibit complex and dynamic rearrangements that shape forming organs, limbs, and body axes. Directed migration, mediolateral intercalation, lumen formation, and other rearrangements influence the topology and topography of developing tissues. These collective cell behaviors are distinct phenomena but all involve the fine-grained control of cell polarity. Here we review recent findings in the dynamics of polarized cell behavior in both the Drosophila ovarian border cells and the Ciona notochord. These studies reveal the remarkable reorganization of cell polarity during organ formation and underscore conserved mechanisms of developmental cell polarity including the Par/atypical protein kinase C (aPKC) and planar cell polarity pathways. These two very different model systems demonstrate important commonalities but also key differences in how cell polarity is controlled in tissue morphogenesis. Together, these systems raise important, broader questions on how the developmental control of cell polarity contributes to morphogenesis of diverse tissues across the metazoa.

  6. Dynamics of cell polarity in tissue morphogenesis: a comparative view from Drosophila and Ciona

    PubMed Central

    Veeman, Michael T.; McDonald, Jocelyn A.

    2016-01-01

    Tissues in developing embryos exhibit complex and dynamic rearrangements that shape forming organs, limbs, and body axes. Directed migration, mediolateral intercalation, lumen formation, and other rearrangements influence the topology and topography of developing tissues. These collective cell behaviors are distinct phenomena but all involve the fine-grained control of cell polarity. Here we review recent findings in the dynamics of polarized cell behavior in both the Drosophila ovarian border cells and the Ciona notochord. These studies reveal the remarkable reorganization of cell polarity during organ formation and underscore conserved mechanisms of developmental cell polarity including the Par/atypical protein kinase C (aPKC) and planar cell polarity pathways. These two very different model systems demonstrate important commonalities but also key differences in how cell polarity is controlled in tissue morphogenesis. Together, these systems raise important, broader questions on how the developmental control of cell polarity contributes to morphogenesis of diverse tissues across the metazoa. PMID:27303647

  7. A saturation screen for cis-acting regulatory DNA in the Hox genes of Ciona intestinalis

    SciTech Connect

    Keys, David N.; Lee, Byung-in; Di Gregorio, Anna; Harafuji, Naoe; Detter, Chris; Wang, Mei; Kahsai, Orsalem; Ahn, Sylvia; Arellano, Andre; Zhang, Quin; Trong, Stephan; Doyle, Sharon A.; Satoh, Noriyuki; Satou, Yutaka; Saiga, Hidetoshi; Christian, Allen; Rokhsar, Dan; Hawkins, Trevor L.; Levine, Mike; Richardson, Paul

    2005-01-05

    A screen for the systematic identification of cis-regulatory elements within large (>100 kb) genomic domains containing Hox genes was performed by using the basal chordate Ciona intestinalis. Randomly generated DNA fragments from bacterial artificial chromosomes containing two clusters of Hox genes were inserted into a vector upstream of a minimal promoter and lacZ reporter gene. A total of 222 resultant fusion genes were separately electroporated into fertilized eggs, and their regulatory activities were monitored in larvae. In sum, 21 separable cis-regulatory elements were found. These include eight Hox linked domains that drive expression in nested anterior-posterior domains of ectodermally derived tissues. In addition to vertebrate-like CNS regulation, the discovery of cis-regulatory domains that drive epidermal transcription suggests that C. intestinalis has arthropod-like Hox patterning in the epidermis.

  8. Optimization of a method for chromatin immunoprecipitation assays in the marine invertebrate chordate Ciona

    PubMed Central

    Aihara, Hitoshi; Katikala, Lavanya; Zeller, Robert W.; Di Gregorio, Anna; Nibu, Yutaka

    2013-01-01

    Chromatin immunoprecipitation (ChIP) assays allow the efficient characterization of the in vivo occupancy of genomic regions by DNA-binding proteins, and thus facilitate the prediction of cis-regulatory sequences in silico and guide their validation in vivo. For these reasons, these assays and their permutations (e.g., ChIP-on-chip, ChIP-Sequencing) are currently being extended to several non-mainstream model organisms, as the availability of specific antibodies increases. Here we describe the development of a polyclonal antibody against the Brachyury protein of the marine invertebrate chordate Ciona intestinalis and provide a detailed ChIP protocol that should be easily adaptable to other marine organisms. PMID:23592257

  9. Distribution and Localised Effects of the Invasive Ascidian Didemnum perlucidum (Monniot 1983) in an Urban Estuary.

    PubMed

    Simpson, Tiffany Schenk; Wernberg, Thomas; McDonald, Justin I

    2016-01-01

    Didemnid ascidians are notorious marine invaders, fouling infrastructure in many ecosystems globally. However, there have been few reports of direct interactions with native species in their natural environment. The invasive colonial ascidian Didemnum perlucidum was discovered in the Swan River estuary (Western Australia) growing on the native seagrass Halophila ovalis. Given the known effects of other related Didemnum species it was expected that D. perlucidum could adversely affect the seagrass, with possible flow on effects to the rest of the ecosystem. This study aimed to document the distribution and abundance of D. perlucidum in the estuary, and to determine whether this species had a negative impact on H. ovalis or associated flora and fauna. D. perlucidum was largely present near areas of infrastructure, particularly mooring buoys, suggesting these were the source of D. perlucidum recruits on the seagrasses. It showed a clear seasonal pattern in abundance, with highly variable cover and colony size. D. perlucidum had a measurable effect on H. ovalis, with colonies enveloping all plant tissue, likely restricting the photosynthetic ability of individual leaves and total plant biomass. There were also significantly less seagrass-associated mud snails (Batillaria australis) where D. perlucidum cover was high. These results demonstrate the ability of invasive ascidians to colonise and affect native seagrasses and associated biota. Seagrasses are pivotal to the ecological function of many urban estuaries world-wide. Biodiversity in these systems is already vulnerable to multiple stressors from human activities but the potential stress of fouling ascidians may pose an additional and increasing threat in the future. PMID:27144600

  10. Prunolides A, B, and C: Novel Tetraphenolic Bis-Spiroketals from the Australian Ascidian Synoicum prunum.

    PubMed

    Carroll, Anthony R.; Healy, Peter C.; Quinn, Ronald J.; Tranter, Carolyn J.

    1999-04-16

    Three novel tetraphenolic bis-spiroketals, prunolides A-C (1, 3, and 4) have been isolated from the Australian ascidian Synoicum prunum. The structures were determined from NMR spectroscopic data and from an X-ray analysis of prunolide A. The prunolides contain a unique 1,6,8-trioxadispiro[4.1.4.2]trideca-3,10,12-triene-2,9-dione carbon skeleton. The known compound rubrolide A (5) was also isolated.

  11. Distribution and Localised Effects of the Invasive Ascidian Didemnum perlucidum (Monniot 1983) in an Urban Estuary.

    PubMed

    Simpson, Tiffany Schenk; Wernberg, Thomas; McDonald, Justin I

    2016-01-01

    Didemnid ascidians are notorious marine invaders, fouling infrastructure in many ecosystems globally. However, there have been few reports of direct interactions with native species in their natural environment. The invasive colonial ascidian Didemnum perlucidum was discovered in the Swan River estuary (Western Australia) growing on the native seagrass Halophila ovalis. Given the known effects of other related Didemnum species it was expected that D. perlucidum could adversely affect the seagrass, with possible flow on effects to the rest of the ecosystem. This study aimed to document the distribution and abundance of D. perlucidum in the estuary, and to determine whether this species had a negative impact on H. ovalis or associated flora and fauna. D. perlucidum was largely present near areas of infrastructure, particularly mooring buoys, suggesting these were the source of D. perlucidum recruits on the seagrasses. It showed a clear seasonal pattern in abundance, with highly variable cover and colony size. D. perlucidum had a measurable effect on H. ovalis, with colonies enveloping all plant tissue, likely restricting the photosynthetic ability of individual leaves and total plant biomass. There were also significantly less seagrass-associated mud snails (Batillaria australis) where D. perlucidum cover was high. These results demonstrate the ability of invasive ascidians to colonise and affect native seagrasses and associated biota. Seagrasses are pivotal to the ecological function of many urban estuaries world-wide. Biodiversity in these systems is already vulnerable to multiple stressors from human activities but the potential stress of fouling ascidians may pose an additional and increasing threat in the future.

  12. When shape matters: strategies of different Antarctic ascidians morphotypes to deal with sedimentation.

    PubMed

    Torre, Luciana; Abele, Doris; Lagger, Cristian; Momo, Fernando; Sahade, Ricardo

    2014-08-01

    Climate change leads to increased melting of tidewater glaciers in the Western Antarctic Peninsula region and sediment bearing glacial melt waters negatively affects filter feeding species as solitary ascidians. In previous work the erect-forms Molgula pedunculata and Cnemidocarpa verrucosa (Order Stolidobranchiata) appeared more sensitive than the flat form Ascidia challengeri (Order Phlebobranchiata). Sedimentation exposure is expected to induce up-regulation of anaerobic metabolism by obstructing the organs of gas exchange (environmental hypoxia) or causes enhanced squirting activity (functional hypoxia). In this study we evaluated the possible relationship between ascidian morphotype and their physiological response to sedimentation. Together with some behavioural observations, we analysed the response of anaerobic metabolic parameters (lactate formation and glycogen consumption) in different tissues of three Antarctic ascidians, exposed to high sediment concentrations (200 mgL(-1)). The results were compared to experimental hypoxia (10% pO2) and exercise (induced muscular contraction) effects, in order to discriminate the effect of sediment on each species and morpho-type (erect vs. flat forms). Our results suggest that the styled (erect) C. verrucosa increases muscular squirting activity in order to expulse excessive material, while the flat-form A. challengeri reacts more passively by down-regulating its aerobic metabolism under sediment exposure. Contrary, the erect ascidian M. pedunculata did not show any measurable response to the treatments, indicating that filtration and ingestion activities were not reduced or altered even under high sedimentation (low energetic material) which could be disadvantageous on the long-term and could explain why M. pedunculata densities decline in the study area.

  13. Distribution and Localised Effects of the Invasive Ascidian Didemnum perlucidum (Monniot 1983) in an Urban Estuary

    PubMed Central

    Wernberg, Thomas; McDonald, Justin I.

    2016-01-01

    Didemnid ascidians are notorious marine invaders, fouling infrastructure in many ecosystems globally. However, there have been few reports of direct interactions with native species in their natural environment. The invasive colonial ascidian Didemnum perlucidum was discovered in the Swan River estuary (Western Australia) growing on the native seagrass Halophila ovalis. Given the known effects of other related Didemnum species it was expected that D. perlucidum could adversely affect the seagrass, with possible flow on effects to the rest of the ecosystem. This study aimed to document the distribution and abundance of D. perlucidum in the estuary, and to determine whether this species had a negative impact on H. ovalis or associated flora and fauna. D. perlucidum was largely present near areas of infrastructure, particularly mooring buoys, suggesting these were the source of D. perlucidum recruits on the seagrasses. It showed a clear seasonal pattern in abundance, with highly variable cover and colony size. D. perlucidum had a measurable effect on H. ovalis, with colonies enveloping all plant tissue, likely restricting the photosynthetic ability of individual leaves and total plant biomass. There were also significantly less seagrass-associated mud snails (Batillaria australis) where D. perlucidum cover was high. These results demonstrate the ability of invasive ascidians to colonise and affect native seagrasses and associated biota. Seagrasses are pivotal to the ecological function of many urban estuaries world-wide. Biodiversity in these systems is already vulnerable to multiple stressors from human activities but the potential stress of fouling ascidians may pose an additional and increasing threat in the future. PMID:27144600

  14. Zorrimidazolone, a Bioactive Alkaloid from the Non-Indigenous Mediterranean Stolidobranch Polyandrocarpa zorritensis

    PubMed Central

    Aiello, Anna; Fattorusso, Ernesto; Imperatore, Concetta; Irace, Carlo; Luciano, Paolo; Menna, Marialuisa; Santamaria, Rita; Vitalone, Rocco

    2011-01-01

    Chemical analysis of the Mediterranean ascidian Polyandrocarpa zorritensis (Van Name 1931) resulted in the isolation of a series of molecules including two monoindole alkaloids, 3-indolylglyoxylic acid (3) and its methyl ester (4), 4-hydroxy-3-methoxyphenylglyoxylic acid methyl ester (1) and a new alkaloid we named zorrimidazolone (2). The structure of the novel compound 2 has been elucidated by spectroscopic analysis and bioactivity of all compounds has been investigated. Zorrimidazolone (2) showed a modest cytotoxic activity against C6 rat glioma cell line. PMID:21747753

  15. Passive flow through an unstalked intertidal ascidian: orientation and morphology enhance suspension feeding in Pyura stolonifera.

    PubMed

    Knott, N A; Davis, A R; Buttemer, W A

    2004-12-01

    Passive flow is believed to increase the gains and reduce the costs of active suspension feeding. We used a mixture of field and laboratory experiments to evaluate whether the unstalked intertidal ascidian Pyura stolonifera exploits passive flow. We predicted that its orientation to prevailing currents and the arrangement of its siphons would induce passive flow due to dynamic pressure at the inhalant siphon, as well as by the Bernoulli effect or viscous entrainment associated with different fluid velocities at each siphon, or by both mechanisms. The orientation of P. stolonifera at several locations along the Sydney-Illawarra coast (Australia) covering a wide range of wave exposures was nonrandom and revealed that the ascidians were consistently oriented with their inhalant siphons directed into the waves or backwash. Flume experiments using wax models demonstrated that the arrangement of the siphons could induce passive flow and that passive flow was greatest when the inhalant siphon was oriented into the flow. Field experiments using transplanted animals confirmed that such an orientation resulted in ascidians gaining food at greater rates, as measured by fecal production, than when oriented perpendicular to the wave direction. We conclude that P. stolonifera enhances suspension feeding by inducing passive flow and is, therefore, a facultatively active suspension feeder. Furthermore, we argue that it is likely that many other active suspension feeders utilize passive flow and, therefore, measurements of their clearance rates should be made under appropriate conditions of flow to gain ecologically relevant results. PMID:15616352

  16. PSP toxins profile in ascidian Microcosmus vulgaris (Heller, 1877) after human poisoning in Croatia (Adriatic Sea).

    PubMed

    Roje-Busatto, Romana; Ujević, Ivana

    2014-03-01

    Toxins known to cause Paralytic Shellfish Poisoning (PSP) syndrome in humans that can have serious economic consequences for aquaculture were determined in ascidians of the genus Microcosmus. Significant concentrations of toxins were confirmed in all tested samples collected from the western coast of Istria Peninsula (Adriatic Sea, Croatia) when six people were poisoned following the consumption of fresh ascidians. Several species of bivalves that were under continuous monitoring had not accumulated PSP toxins although they were exposed to the same environmental conditions over the survey period. In the present study, HPLC-FLD with pre-column oxidation of PSP toxins has been carried out to provide evidence for the first human intoxication due to consumption of PSP toxic ascidians (Microcosmus vulgaris, Heller, 1877) harvested from the Adriatic Sea. Qualitative analysis established the presence of six PSP toxins: saxitoxin (STX), decarbamoylsaxitoxin (dcSTX), gonyautoxins 2 and 3 (GTX2,3), decarbamoylgonyautoxins 2 and 3 (dcGTX2,3), gonyautoxin 5 (GTX5) and N-sulfocarbamoylgonyautoxins 1 and 2 (C1,2), while quantitative analysis suggested STX and GTX2,3 as dominant toxin types and the ones that contribute the most to the overall toxicity of these samples with concentrations near the regulatory limit.

  17. Encystment and excystment of kinetoplastid Azumiobodo hoyamushi, causal agent of soft tunic syndrome in ascidian aquaculture.

    PubMed

    Nawata, Akatsuki; Hirose, Euichi; Kitamura, Shin-Ichi; Kumagai, Akira

    2015-08-20

    Soft tunic syndrome in the edible ascidian Halocynthia roretzi is caused by the kinetoplastid flagellate Azumiobodo hoyamushi, which was found to assume a fusiform cell form with 2 flagella in axenic, pure culture. When the flagellate form was incubated in sterilized artificial seawater (pH 8.4), some of the cells became cyst-like and adhered to the bottom of the culture plate. The cyst-like forms were spherical or cuboidal, and each had 2 flagella encapsulated in its cytoplasm. Encystment was also induced in culture medium alkalified to the pH of seawater (8.4) but not in unmodified (pH 7.2) or acidified media (pH 6.4). More than 95% of the cyst-like cells converted to the flagellate form within 1 d following transfer to seawater containing ascidian tunic extracts from host ascidians. The cyst-like cells were able to survive in seawater with no added nutrients for up to 2 wk at 20°C and for a few months at 5 to 15°C. The survival period in seawater depended on temperature: some cyst-like cells survived 3 mo at 10°C, and ca. 95% of these converted to flagellate forms in seawater containing tunic extracts. Thus, A. hoyamushi is able to persist under adverse conditions in a cyst-like form able to adhere to organic and inorganic substrata for protracted periods of time. PMID:26290510

  18. Encystment and excystment of kinetoplastid Azumiobodo hoyamushi, causal agent of soft tunic syndrome in ascidian aquaculture.

    PubMed

    Nawata, Akatsuki; Hirose, Euichi; Kitamura, Shin-Ichi; Kumagai, Akira

    2015-08-20

    Soft tunic syndrome in the edible ascidian Halocynthia roretzi is caused by the kinetoplastid flagellate Azumiobodo hoyamushi, which was found to assume a fusiform cell form with 2 flagella in axenic, pure culture. When the flagellate form was incubated in sterilized artificial seawater (pH 8.4), some of the cells became cyst-like and adhered to the bottom of the culture plate. The cyst-like forms were spherical or cuboidal, and each had 2 flagella encapsulated in its cytoplasm. Encystment was also induced in culture medium alkalified to the pH of seawater (8.4) but not in unmodified (pH 7.2) or acidified media (pH 6.4). More than 95% of the cyst-like cells converted to the flagellate form within 1 d following transfer to seawater containing ascidian tunic extracts from host ascidians. The cyst-like cells were able to survive in seawater with no added nutrients for up to 2 wk at 20°C and for a few months at 5 to 15°C. The survival period in seawater depended on temperature: some cyst-like cells survived 3 mo at 10°C, and ca. 95% of these converted to flagellate forms in seawater containing tunic extracts. Thus, A. hoyamushi is able to persist under adverse conditions in a cyst-like form able to adhere to organic and inorganic substrata for protracted periods of time.

  19. Genome-wide identification and characterization of transcription start sites and promoters in the tunicate Ciona intestinalis.

    PubMed

    Yokomori, Rui; Shimai, Kotaro; Nishitsuji, Koki; Suzuki, Yutaka; Kusakabe, Takehiro G; Nakai, Kenta

    2016-01-01

    The tunicate Ciona intestinalis, an invertebrate chordate, has recently emerged as a powerful model organism for gene regulation analysis. However, few studies have been conducted to identify and characterize its transcription start sites (TSSs) and promoters at the genome-wide level. Here, using TSS-seq, we identified TSSs at the genome-wide scale and characterized promoters in C. intestinalis. Specifically, we identified TSS clusters (TSCs), high-density regions of TSS-seq tags, each of which appears to originate from an identical promoter. TSCs were found not only at known TSSs but also in other regions, suggesting the existence of many unknown transcription units in the genome. We also identified candidate promoters of 79 ribosomal protein (RP) genes, each of which had the major TSS in a polypyrimidine tract and showed a sharp TSS distribution like human RP gene promoters. Ciona RP gene promoters, however, did not appear to have typical TATA boxes, unlike human RP gene promoters. In Ciona non-RP promoters, two pyrimidine-purine dinucleotides, CA and TA, were frequently used as TSSs. Despite the absence of CpG islands, Ciona TATA-less promoters showed low expression specificity like CpG-associated human TATA-less promoters. By using TSS-seq, we also predicted trans-spliced gene TSSs and found that their downstream regions had higher G+T content than those of non-trans-spliced gene TSSs. Furthermore, we identified many putative alternative promoters, some of which were regulated in a tissue-specific manner. Our results provide valuable information about TSSs and promoter characteristics in C. intestinalis and will be helpful in future analysis of transcriptional regulation in chordates. PMID:26668163

  20. Nitric Oxide Acts as a Positive Regulator to Induce Metamorphosis of the Ascidian Herdmania momus

    PubMed Central

    Ueda, Nobuo; Degnan, Sandie M.

    2013-01-01

    Marine invertebrates commonly have a biphasic life cycle in which the metamorphic transition from a pelagic larva to a benthic post-larva is mediated by the nitric oxide signalling pathway. Nitric oxide (NO) is synthesised by nitric oxide synthase (NOS), which is a client protein of the molecular chaperon heat shock protein 90 (HSP90). It is notable, then, that both NO and HSP90 have been implicated in regulating metamorphosis in marine invertebrates as diverse as urochordates, echinoderms, molluscs, annelids, and crustaceans. Specifically, the suppression of NOS activity by the application of either NOS- or HSP90-inhibiting pharmacological agents has been shown consistently to induce the initiation of metamorphosis, leading to the hypothesis that a negative regulatory role of NO is widely conserved in biphasic life cycles. Further, the induction of metamorphosis by heat-shock has been demonstrated for multiple species. Here, we investigate the regulatory role of NO in induction of metamorphosis of the solitary tropical ascidian, Herdmania momus. By coupling pharmacological treatments with analysis of HmNOS and HmHSP90 gene expression, we present compelling evidence of a positive regulatory role for NO in metamorphosis of this species, in contrast to all existing ascidian data that supports the hypothesis of NO as a conserved negative regulator of metamorphosis. The exposure of competent H. momus larvae to a NOS inhibitor or an NO donor results in an up-regulation of NOS and HSP90 genes. Heat shock of competent larvae induces metamorphosis in a temperature dependent manner, up to a thermal tolerance that approaches 35°C. Both larval/post-larval survival and the appearance of abnormal morphologies in H. momus post-larvae reflect the magnitude of up-regulation of the HSP90 gene in response to heat-shock. The demonstrated role of NO as a positive metamorphic regulator in H. momus suggests the existence of inter-specific adaptations of NO regulation in ascidian

  1. Nitric oxide acts as a positive regulator to induce metamorphosis of the ascidian Herdmania momus.

    PubMed

    Ueda, Nobuo; Degnan, Sandie M

    2013-01-01

    Marine invertebrates commonly have a biphasic life cycle in which the metamorphic transition from a pelagic larva to a benthic post-larva is mediated by the nitric oxide signalling pathway. Nitric oxide (NO) is synthesised by nitric oxide synthase (NOS), which is a client protein of the molecular chaperon heat shock protein 90 (HSP90). It is notable, then, that both NO and HSP90 have been implicated in regulating metamorphosis in marine invertebrates as diverse as urochordates, echinoderms, molluscs, annelids, and crustaceans. Specifically, the suppression of NOS activity by the application of either NOS- or HSP90-inhibiting pharmacological agents has been shown consistently to induce the initiation of metamorphosis, leading to the hypothesis that a negative regulatory role of NO is widely conserved in biphasic life cycles. Further, the induction of metamorphosis by heat-shock has been demonstrated for multiple species. Here, we investigate the regulatory role of NO in induction of metamorphosis of the solitary tropical ascidian, Herdmania momus. By coupling pharmacological treatments with analysis of HmNOS and HmHSP90 gene expression, we present compelling evidence of a positive regulatory role for NO in metamorphosis of this species, in contrast to all existing ascidian data that supports the hypothesis of NO as a conserved negative regulator of metamorphosis. The exposure of competent H. momus larvae to a NOS inhibitor or an NO donor results in an up-regulation of NOS and HSP90 genes. Heat shock of competent larvae induces metamorphosis in a temperature dependent manner, up to a thermal tolerance that approaches 35°C. Both larval/post-larval survival and the appearance of abnormal morphologies in H. momus post-larvae reflect the magnitude of up-regulation of the HSP90 gene in response to heat-shock. The demonstrated role of NO as a positive metamorphic regulator in H. momus suggests the existence of inter-specific adaptations of NO regulation in ascidian

  2. Microbial diversity of biofilm communities in microniches associated with the didemnid ascidian Lissoclinum patella

    PubMed Central

    Behrendt, Lars; Larkum, Anthony W D; Trampe, Erik; Norman, Anders; Sørensen, Søren J; Kühl, Michael

    2012-01-01

    We assessed the microbial diversity and microenvironmental niche characteristics in the didemnid ascidian Lissoclinum patella using 16S rRNA gene sequencing, microsensor and imaging techniques. L. patella harbors three distinct microbial communities spatially separated by few millimeters of tunic tissue: (i) a biofilm on its upper surface exposed to high irradiance and O2 levels, (ii) a cloacal cavity dominated by the prochlorophyte Prochloron spp. characterized by strong depletion of visible light and a dynamic chemical microenvironment ranging from hyperoxia in light to anoxia in darkness and (iii) a biofilm covering the underside of the animal, where light is depleted of visible wavelengths and enriched in near-infrared radiation (NIR). Variable chlorophyll fluorescence imaging demonstrated photosynthetic activity, and hyperspectral imaging revealed a diversity of photopigments in all microhabitats. Amplicon sequencing revealed the dominance of cyanobacteria in all three layers. Sequences representing the chlorophyll d containing cyanobacterium Acaryochloris marina and anoxygenic phototrophs were abundant on the underside of the ascidian in shallow waters but declined in deeper waters. This depth dependency was supported by a negative correlation between A. marina abundance and collection depth, explained by the increased attenuation of NIR as a function of water depth. The combination of microenvironmental analysis and fine-scale sampling techniques used in this investigation gives valuable first insights into the distribution, abundance and diversity of bacterial communities associated with tropical ascidians. In particular, we show that microenvironments and microbial diversity can vary significantly over scales of a few millimeters in such habitats; which is information easily lost by bulk sampling. PMID:22134643

  3. Anti-inflammatory and antimalarial meroterpenoids from the New Zealand ascidian Aplidium scabellum.

    PubMed

    Chan, Susanna T S; Pearce, A Norrie; Januario, Ana H; Page, Michael J; Kaiser, Marcel; McLaughlin, Rene J; Harper, Jacquie L; Webb, Victoria L; Barker, David; Copp, Brent R

    2011-11-01

    Bioassay-directed fractionation of an extract of the New Zealand ascidian Aplidium scabellum has afforded the anti-inflammatory secondary metabolite 2-geranyl-6-methoxy-1,4-hydroquinone-4-sulfate (1) and a family of pseudodimeric meroterpenoids scabellones A (2)-D (5). The benzo[c]chromene-7,10-dione scaffold contained within scabellones A-D is particularly rare among natural products. The structures were elucidated by interpretation of NMR data. Scabellone B was also identified as a moderately potent, nontoxic inhibitor of Plasmodium falciparum.

  4. Rubrolide R: a new furanone metabolite from the ascidian Synoicum of the Indian Ocean.

    PubMed

    Smitha, Desaraju; Kumar, Muthyala Murali Krishna; Ramana, Hechhu; Rao, Desaraju Venkata

    2014-01-01

    A new furanone metabolite of the rubrolide family, rubrolide R as diacetate (1), was isolated from a new species of the ascidian Synoicum, besides the known compounds rubrolide A (as diacetate), cadiolide B and prunolide A. The structure of the new rubrolide was elucidated by a study of spectral data. The crude extract and isolated compounds (prunolide A and cadiolide B) showed antiviral activity against the Japanese encephalitis virus. Prunolide A showed cytotoxic activity against breast cancer cell lines at a concentration of < 1 μM.

  5. Sagitol D, a New Thiazole Containing Pyridoacridine Alkaloid from a Vietnamese Ascidian.

    PubMed

    Utkina, Natalia K

    2015-09-01

    A new thiazole containing pyridoacridine alkaloid, named sagitol D (1), and five known alkaloids kuanoniaminesA (2), C (3), D (4), E (5), and F (6), have been isolated from an unidentified Vietnamese ascidian. The structure of the new compound was established from NMR spectroscopic data. Kuanoniamines C, D, E, and F showed moderate antioxidant activity in the DPPH (IC50 36 µM) and ABTS assays (TE = 0.5), while sagitol D showed weak activity (IC50 92 M;TE = 0.10), and kuanoniamine A was inactive. PMID:26594755

  6. The alien ascidian Styela clava now invading the Sea of Marmara (Tunicata: Ascidiacea)

    PubMed Central

    Çinar, Melih Ertan

    2016-01-01

    Abstract During the implementation of a large project aimed to investigate the benthic community structures of the Sea of Marmara, specimens of the invasive ascidian species Styela clava were collected on natural substrata (rocks) at 10 m depth at one locality (Karamürsel) in İzmit Bay. The specimens were mature, containing gametes, indicating that the species had become established in the area. The Sea of Marmara seems to provide suitable conditions for this species to survive and form proliferating populations. PMID:27047235

  7. Raman Spectroscopic Imaging of the Whole Ciona intestinalis Embryo during Development

    PubMed Central

    Nakamura, Mitsuru J.; Hotta, Kohji; Oka, Kotaro

    2013-01-01

    Intracellular composition and the distribution of bio-molecules play central roles in the specification of cell fates and morphogenesis during embryogenesis. Consequently, investigation of changes in the expression and distribution of bio-molecules, especially mRNAs and proteins, is an important challenge in developmental biology. Raman spectroscopic imaging, a non-invasive and label-free technique, allows simultaneous imaging of the intracellular composition and distribution of multiple bio-molecules. In this study, we explored the application of Raman spectroscopic imaging in the whole Ciona intestinalis embryo during development. Analysis of Raman spectra scattered from C. intestinalis embryos revealed a number of localized patterns of high Raman intensity within the embryo. Based on the observed distribution of bio-molecules, we succeeded in identifying the location and structure of differentiated muscle and endoderm within the whole embryo, up to the tailbud stage, in a label-free manner. Furthermore, during cell differentiation, we detected significant differences in cell state between muscle/endoderm daughter cells and daughter cells with other fates that had divided from the same mother cells; this was achieved by focusing on the Raman intensity of single Raman bands at 1002 or 1526 cm−1, respectively. This study reports the first application of Raman spectroscopic imaging to the study of identifying and characterizing differentiating tissues in a whole chordate embryo. Our results suggest that Raman spectroscopic imaging is a feasible label-free technique for investigating the developmental process of the whole embryo of C. intestinalis. PMID:23977129

  8. Expression of the Ciona intestinalis alternative oxidase (AOX) in Drosophila complements defects in mitochondrial oxidative phosphorylation.

    PubMed

    Fernandez-Ayala, Daniel J M; Sanz, Alberto; Vartiainen, Suvi; Kemppainen, Kia K; Babusiak, Marek; Mustalahti, Eero; Costa, Rodolfo; Tuomela, Tea; Zeviani, Massimo; Chung, Jongkyeong; O'Dell, Kevin M C; Rustin, Pierre; Jacobs, Howard T

    2009-05-01

    Defects in mitochondrial OXPHOS are associated with diverse and mostly intractable human disorders. The single-subunit alternative oxidase (AOX) found in many eukaryotes, but not in arthropods or vertebrates, offers a potential bypass of the OXPHOS cytochrome chain under conditions of pathological OXPHOS inhibition. We have engineered Ciona intestinalis AOX for conditional expression in Drosophila melanogaster. Ubiquitous AOX expression produced no detrimental phenotype in wild-type flies. However, mitochondrial suspensions from AOX-expressing flies exhibited a significant cyanide-resistant substrate oxidation, and the flies were partially resistant to both cyanide and antimycin. AOX expression was able to complement the semilethality of partial knockdown of both cyclope (COXVIc) and the complex IV assembly factor Surf1. It also rescued the locomotor defect and excess mitochondrial ROS production of flies mutated in dj-1beta, a Drosophila homolog of the human Parkinson's disease gene DJ1. AOX appears to offer promise as a wide-spectrum therapeutic tool in OXPHOS disorders. PMID:19416715

  9. Regeneration, Stem Cells, and Aging in the Tunicate Ciona: Insights from the Oral Siphon.

    PubMed

    Jeffery, William R

    2015-01-01

    Regeneration studies in the tunicate Ciona intestinalis have recently been focused on the potential of adult stem cells to replace injured tissues and organs during the adult life cycle using the oral siphon (OS) as a model. The OS has oral siphon pigment organs (OPOs) along its rim and an underlying network of muscle fibers in its tube. Different regeneration processes are triggered by OS amputation at the tip, along the tube, or at the base. One process involves the replacement of OPOs without new cell division by direct differentiation of locally deployed stem cells or stem cells that migrate from the branchial sac. Another process involves blastema formation by the migration of progenitor cells produced from branchial sac stem cells. The capacity for complete and accurate OS regeneration declines continuously during the adult life cycle. Finally, after an age threshold is reached, OS regeneration ceases in old animals. The loss of regeneration capacity in old animals involves the depletion of stem cells in the branchial sac, the inability of branchial sac progenitor cells to migrate to the sites of regeneration, and defective oral pigment organ replacement. The significance of the OS model for studying regeneration, stem cells, and aging will be enhanced by the application of molecular methods.

  10. Isolation of a novel LPS-induced component of the ML superfamily in Ciona intestinalis.

    PubMed

    Vizzini, Aiti; Bonura, Angela; Longo, Valeria; Sanfratello, Maria Antonietta; Parrinello, Daniela; Cammarata, Matteo; Colombo, Paolo

    2015-11-01

    ML superfamily represents a group of proteins playing important roles in lipid metabolism and innate immune response. In this study, we report the identification of the first component of the ML superfamily in the invertebrate Ciona intestinalis by means of a subtractive hybridization strategy. Sequence homology and phylogenetic analysis showed that this protein forms a specific clade with vertebrate components of the Niemann-Pick type C2 protein and, for this reason, it has been named Ci-NPC2. The putative Ci-NPC2 is a 150 amino acids long protein with a short signal peptide, seven cysteine residues, three putative lipid binding site and a three-dimensional model showing a characteristic β-strand structure. Gene expression analysis demonstrated that the Ci-NPC2 protein is positively upregulated after LPS inoculum with a peak of expression 1 h after challenge. Finally, in-situ hybridization demonstrated that the Ci-NPC2 protein is preferentially expressed in hemocytes inside the vessel lumen. PMID:26159403

  11. Preparation and Antitumor Activity of CS5931, A Novel Polypeptide from Sea Squirt Ciona Savignyi

    PubMed Central

    Chen, Xiaoshuang; Xu, Huanli; Li, Bo; Wang, Feng; Chen, Xiaoliang; Kong, Dexin; Lin, Xiukun

    2016-01-01

    CS5931 is a novel anticancer agent isolated from the sea squirt Ciona savignyi. However, its content in the species is very low, and developing a novel approach for production of the polypeptide is promising. In the present study, we expressed and purified the polypeptide from E. coli, and the fermentation conditions were studied using response surface methodology. The yield of CS5931 was increased from 2.0 to 7.5 mg/L. The denaturing and renaturation conditions were also studied. Using the optimized renaturation condition, the anticancer activity of refolding CS5931 was increased significantly; the value of IC50 was decreased from 23.2 to 11.6 μM. In vivo study using xenograft nude mice bearing HCT116 cancer cells revealed that CS5931 was able to inhibit the growth of tumor significantly. The study provides a useful approach for obtaining enough amount of CS5931 for further study. This study is also important for developing the polypeptide as a novel anticancer agent. PMID:27007382

  12. Regeneration, Stem Cells, and Aging in the Tunicate Ciona: Insights from the Oral Siphon.

    PubMed

    Jeffery, William R

    2015-01-01

    Regeneration studies in the tunicate Ciona intestinalis have recently been focused on the potential of adult stem cells to replace injured tissues and organs during the adult life cycle using the oral siphon (OS) as a model. The OS has oral siphon pigment organs (OPOs) along its rim and an underlying network of muscle fibers in its tube. Different regeneration processes are triggered by OS amputation at the tip, along the tube, or at the base. One process involves the replacement of OPOs without new cell division by direct differentiation of locally deployed stem cells or stem cells that migrate from the branchial sac. Another process involves blastema formation by the migration of progenitor cells produced from branchial sac stem cells. The capacity for complete and accurate OS regeneration declines continuously during the adult life cycle. Finally, after an age threshold is reached, OS regeneration ceases in old animals. The loss of regeneration capacity in old animals involves the depletion of stem cells in the branchial sac, the inability of branchial sac progenitor cells to migrate to the sites of regeneration, and defective oral pigment organ replacement. The significance of the OS model for studying regeneration, stem cells, and aging will be enhanced by the application of molecular methods. PMID:26404471

  13. The recently-described ascidian species Molgula tectiformis is a direct developer.

    PubMed

    Tagawa, K; Jeffery, W R; Satoh, N

    1997-04-01

    Molgula tectiformis is a new ascidian species recently described by Nishikawa (1991). In Otsuchi Bay, Iwate, Japan, they are easily obtainable from cages for culturing scallops. We report here that M. tectiformis is another example of a direct developer: their embryonic development is lacking the tadpole larva. The fertilized egg is orange and about 150 microns in diameter. At 18 degrees C, the egg cleaves at about 20 min intervals and gastrulation occurs about 5 hr after fertilization. In contrast to conventionally-developing ascidians, M. tectiformis does not form a tadpole larva. Immediately before hatching, three stolons or ampullae begin to extend from the tailless embryo. After hatching the stolons mediate the attachment of the juvenile body to the substratum. Histochemistry for tissue-specific enzyme activity did not detect muscle-specific acetyl-cholinesterase, endoderm-specific alkaline phosphatase, and pigment cell-specific tyrosinase. In addition, in situ hybridization could not prove the presence of muscle actin gene transcripts in the embryo. These results suggest that these larval tissues do not differentiate in M. tectiformis embryos. Because M. tectiformis is common and gravid year-around in Otsuchi Bay, this direct developer provides the opportunity for further analysis of molecular changes during evolution that cause an alternative mode of development.

  14. Distinct modes of mitotic spindle orientation align cells in the dorsal midline of ascidian embryos.

    PubMed

    Negishi, Takefumi; Yasuo, Hitoyoshi

    2015-12-01

    The orientation of cell division can have important consequences on the choice of cell fates adopted by each daughter cell as well as on the architecture of the tissue within which the dividing cell resides. We have studied in detail the oriented cell divisions that take place in the dorsal midline of the ascidian embryo. The dorsal midline cells of the ascidian embryo emerge following an asymmetric cell division oriented along the animal-vegetal (A-V) axis. This division generates the NN (Notochord-Neural) cell at the margin and the E (Endoderm) cell more vegetally. Deviating from the default mode of cell division, these sister cells divide again along the A-V axis to generate a column of four cells. We describe these cell divisions in detail. We show that the NN cell mitotic spindle rotates 90° to align along the A-V axis while the E cell spindle forms directly along the axis following the asymmetric migration of its centrosomes. We combine live imaging, embryo manipulations and pharmacological modulation of cytoskeletal elements to address the mechanisms underlying these distinct subcellular behaviours. Our evidence suggests that, in E cells, aster asymmetry together with the E cell shape contribute to the asymmetric centrosome migration. In NN cells, an intrinsic cytoplasmic polarisation of the cell results in the accumulation of dynein to the animal pole side. Our data support a model in which a dynein-dependent directional cytoplasmic pulling force may be responsible for the NN cell spindle rotation. PMID:26452428

  15. Analysis of the Henze precipitate from the blood cells of the ascidian Phallusia mammillata

    NASA Astrophysics Data System (ADS)

    Ciancio, Aurelio; Scippa, Silvia; Nette, Geoffrey; De Vincentiis, Mario

    The Henze precipitate, a peculiar blue-green microparticulate obtained by lysis of the blood cells of the ascidian Phallusia mammillata (Protochordata), was investigated with atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray microanalysis. The precipitate was collected from the Henze solution, an unstable red-brown product obtained by treating blood with distilled water, whose degradation yields a characteristic blue-green product. The microparticulates measured 50-100 µm in diameter and appeared irregular in shape. SEM examination showed smooth, roughly round boundaries. The microparticulate surface examined with AFM appeared as an irregular matrix formed by 70-320-nm-wide mammillate composites, including and embedding small (500-800 nm wide) crystal-like multilayered formations. X- ray analysis showed that the elements present in these same precipitates were mainly C, Si, Al and O. The microparticulate composition appeared close to those of natural waxes or lacquers, embedding amorphous silicates and/or other Si-Al components. The unusual occurrence of Si in ascidian blood and its role are discussed.

  16. Distinct modes of mitotic spindle orientation align cells in the dorsal midline of ascidian embryos.

    PubMed

    Negishi, Takefumi; Yasuo, Hitoyoshi

    2015-12-01

    The orientation of cell division can have important consequences on the choice of cell fates adopted by each daughter cell as well as on the architecture of the tissue within which the dividing cell resides. We have studied in detail the oriented cell divisions that take place in the dorsal midline of the ascidian embryo. The dorsal midline cells of the ascidian embryo emerge following an asymmetric cell division oriented along the animal-vegetal (A-V) axis. This division generates the NN (Notochord-Neural) cell at the margin and the E (Endoderm) cell more vegetally. Deviating from the default mode of cell division, these sister cells divide again along the A-V axis to generate a column of four cells. We describe these cell divisions in detail. We show that the NN cell mitotic spindle rotates 90° to align along the A-V axis while the E cell spindle forms directly along the axis following the asymmetric migration of its centrosomes. We combine live imaging, embryo manipulations and pharmacological modulation of cytoskeletal elements to address the mechanisms underlying these distinct subcellular behaviours. Our evidence suggests that, in E cells, aster asymmetry together with the E cell shape contribute to the asymmetric centrosome migration. In NN cells, an intrinsic cytoplasmic polarisation of the cell results in the accumulation of dynein to the animal pole side. Our data support a model in which a dynein-dependent directional cytoplasmic pulling force may be responsible for the NN cell spindle rotation.

  17. Expression and function of myc during asexual reproduction of the budding ascidian Polyandrocarpa misakiensis.

    PubMed

    Fujiwara, Shigeki; Isozaki, Takaomi; Mori, Kyoko; Kawamura, Kazuo

    2011-12-01

    The budding ascidian Polyandrocarpa misakiensis proliferates asexually by budding. The atrial epithelium is a multipotent but differentiated tissue, which transdifferentiates into various tissues and organs after the bud separates from the parental body. We isolated cDNA clones homologous to the myc proto-oncogene from P. misakiensis. The cDNA, named Pm-myc, encoded a polypeptide of 639 amino acid residues, containing Myc-specific functional motifs, Myc box I and Myc box II, and the basic helix-loop-helix domain. Expression of Pm-myc was observed in the atrial epithelium in the organ-forming region of the developing bud, where the epithelial cells dedifferentiate and re-enter the cell cycle. The expression was also observed in fibroblast-like cells, which are known to participate in the organogenesis together with the epithelial cells. Unexpectedly, the atrial epithelium expressed Pm-myc more than one day before the dedifferentiation. The organogenesis was disturbed by Pm-myc-specific double-stranded RNA. In situ hybridization revealed that Pm-myc-positive fibroblast-like cells disappeared around the organ primordium of the dsRNA-treated bud. The results suggest that the mesenchymal-epithelial transition of fibroblast-like cells is important for the organogenesis in this budding ascidian species.

  18. Selective Detection and Phylogenetic Diversity of Acaryochloris spp. That Exist in Association with Didemnid Ascidians and Sponge

    PubMed Central

    Ohkubo, Satoshi; Miyashita, Hideaki

    2012-01-01

    Acaryochloris spp. are unique cyanobacteria which contain chlorophyll d as the predominant pigment. The phylogenetic diversity of Acaryochloris spp. associated with 7 Prochloron- or Synechocystis-containing didemnid ascidians and 1 Synechococcus-containing sponge obtained from the coast of the Republic of Palau was analyzed; we established a PCR primer set designed to selectively amplify the partial 16S rRNA gene of Acaryochloris spp. even in DNA samples containing a large amount of other cyanobacterial and algal DNAs. Polymerase chain reaction-denaturing gradient gel electrophoresis with this primer set enabled detection of the phyogenetic diversity of Acaryochloris spp. All the ascidian and sponge samples contained Acaryochloris spp. Fourteen phylotypes that were highly homologous (98–100%) with A. marina MBIC11017 were detected, while only 2 phylotypes were detected with our previously developed method for detecting cyanobacteria. The results also revealed that many uncultured phylotypes of Acaryochloris spp. were associated with those didemnid ascidians, since a clonal culture of only 1 phylotype has been established thus far. No specific relationship was found among the Acaryochloris phylotypes and the genera of the ascidians even when sample localities were identical; therefore, these invertebrates may provide a favorable habitat for Acaryochloris spp. rather than hosts showing any specific symbiotic relationships. PMID:22353766

  19. E/Z-rubrolide O, an anti-inflammatory halogenated furanone from the New Zealand ascidian Synoicum n. sp.

    PubMed

    Pearce, A Norrie; Chia, Elizabeth W; Berridge, Michael V; Maas, Elizabeth W; Page, Michael J; Webb, Victoria L; Harper, Jacquie L; Copp, Brent R

    2007-01-01

    Bioassay-directed fractionation of extracts of a Synoicum n. sp. ascidian from New Zealand led to the isolation of the principal anti-inflammatory component, which was identified by spectroscopic methods as a new member of the rubrolide family, rubrolide O (1), existing as a mixture of E/Z isomers.

  20. Diiron centre mutations in Ciona intestinalis alternative oxidase abolish enzymatic activity and prevent rescue of cytochrome oxidase deficiency in flies

    PubMed Central

    Andjelković, Ana; Oliveira, Marcos T.; Cannino, Giuseppe; Yalgin, Cagri; Dhandapani, Praveen K.; Dufour, Eric; Rustin, Pierre; Szibor, Marten; Jacobs, Howard T.

    2015-01-01

    The mitochondrial alternative oxidase, AOX, carries out the non proton-motive re-oxidation of ubiquinol by oxygen in lower eukaryotes, plants and some animals. Here we created a modified version of AOX from Ciona instestinalis, carrying mutations at conserved residues predicted to be required for chelation of the diiron prosthetic group. The modified protein was stably expressed in mammalian cells or flies, but lacked enzymatic activity and was unable to rescue the phenotypes of flies knocked down for a subunit of cytochrome oxidase. The mutated AOX transgene is thus a potentially useful tool in studies of the physiological effects of AOX expression. PMID:26672986

  1. 3-acetylpyridine-induced degeneration in the adult ascidian neural complex: Reactive and regenerative changes in glia and blood cells.

    PubMed

    Medina, Bianca N S P; Santos de Abreu, Isadora; Cavalcante, Leny A; Silva, Wagner A B; da Fonseca, Rodrigo N; Allodi, Silvana; de Barros, Cintia M

    2015-08-01

    Ascidians are interesting neurobiological models because of their evolutionary position as a sister-group of vertebrates and the high regenerative capacity of their central nervous system (CNS). We investigated the degeneration and regeneration of the cerebral ganglion complex of the ascidian Styela plicata following injection of the niacinamide antagonist 3-acetylpyridine (3AP), described as targeting the CNS of several vertebrates. For the analysis and establishment of a new model in ascidians, the ganglion complex was dissected and prepared for transmission electron microscopy (TEM), routine light microscopy (LM), immunohistochemistry and Western blotting, 1 or 10 days after injection of 3AP. The siphon stimulation test (SST) was used to quantify the functional response. One day after the injection of 3AP, CNS degeneration and recruitment of a non-neural cell type to the site of injury was observed by both TEM and LM. Furthermore, weaker immunohistochemical reactions for astrocytic glial fibrillary acidic protein (GFAP) and neuronal βIII-tubulin were observed. In contrast, the expression of caspase-3, a protein involved in the apoptotic pathway, and the glycoprotein CD34, a marker for hematopoietic stem cells, increased. Ten days after the injection of 3AP, the expression of markers tended toward the original condition. The SST revealed attenuation and subsequent recovery of the reflexes from 1 to 10 days after 3AP. Therefore, we have developed a new method to study ascidian neural degeneration and regeneration, and identified the decreased expression of GFAP and recruitment of blood stem cells to the damaged ganglion as reasons for the success of neuroregeneration in ascidians.

  2. The Simple Chordate Ciona intestinalis Has a Reduced Complement of Genes Associated with Fanconi Anemia.

    PubMed

    Stanley, Edward C; Azzinaro, Paul A; Vierra, David A; Howlett, Niall G; Irvine, Steven Q

    2016-01-01

    Fanconi anemia (FA) is a human genetic disease characterized by congenital defects, bone marrow failure, and increased cancer risk. FA is associated with mutation in one of 24 genes. The protein products of these genes function cooperatively in the FA pathway to orchestrate the repair of DNA interstrand cross-links. Few model organisms exist for the study of FA. Seeking a model organism with a simpler version of the FA pathway, we searched the genome of the simple chordate Ciona intestinalis for homologs of the human FA-associated proteins. BLAST searches, sequence alignments, hydropathy comparisons, maximum likelihood phylogenetic analysis, and structural modeling were used to infer the likelihood of homology between C. intestinalis and human FA proteins. Our analysis indicates that C. intestinalis indeed has a simpler and potentially functional FA pathway. The C. intestinalis genome was searched for candidates for homology to 24 human FA and FA-associated proteins. Support was found for the existence of homologs for 13 of these 24 human genes in C. intestinalis. Members of each of the three commonly recognized FA gene functional groups were found. In group I, we identified homologs of FANCE, FANCL, FANCM, and UBE2T/FANCT. Both members of group II, FANCD2 and FANCI, have homologs in C. intestinalis. In group III, we found evidence for homologs of FANCJ, FANCO, FANCQ/ERCC4, FANCR/RAD51, and FANCS/BRCA1, as well as the FA-associated proteins ERCC1 and FAN1. Evidence was very weak for the existence of homologs in C. intestinalis for any other recognized FA genes. This work supports the notion that C. intestinalis, as a close relative of vertebrates, but having a much reduced complement of FA genes, offers a means of studying the function of certain FA proteins in a simpler pathway than that of vertebrate cells. PMID:27279728

  3. Identical sets of methylated and nonmethylated genes in Ciona intestinalis sperm and muscle cells

    PubMed Central

    2013-01-01

    Background The discovery of gene body methylation, which refers to DNA methylation within gene coding region, suggests an as yet unknown role of DNA methylation at actively transcribed genes. In invertebrates, gene bodies are the primary targets of DNA methylation, and only a subset of expressed genes is modified. Results Here we investigate the tissue variability of both the global levels and distribution of 5-methylcytosine (5mC) in the sea squirt Ciona intestinalis. We find that global 5mC content of early developmental embryos is high, but is strikingly reduced in body wall tissues. We chose sperm and adult muscle cells, with high and reduced levels of global 5mC respectively, for genome-wide analysis of 5mC targets. By means of CXXC-affinity purification followed by deep sequencing (CAP-seq), and genome-wide bisulfite sequencing (BS-seq), we designated body-methylated and unmethylated genes in each tissue. Surprisingly, body-methylated and unmethylated gene groups are identical in the sperm and muscle cells. Our analysis of microarray expression data shows that gene body methylation is associated with broad expression throughout development. Moreover, transgenic analysis reveals contrasting gene body methylation at an identical gene-promoter combination when integrated at different genomic sites. Conclusions We conclude that gene body methylation is not a direct regulator of tissue specific gene expression in C. intestinalis. Our findings reveal constant targeting of gene body methylation irrespective of cell type, and they emphasize a correlation between gene body methylation and ubiquitously expressed genes. Our transgenic experiments suggest that the promoter does not determine the methylation status of the associated gene body. PMID:24279449

  4. The Simple Chordate Ciona intestinalis Has a Reduced Complement of Genes Associated with Fanconi Anemia

    PubMed Central

    Stanley, Edward C.; Azzinaro, Paul A.; Vierra, David A.; Howlett, Niall G.; Irvine, Steven Q.

    2016-01-01

    Fanconi anemia (FA) is a human genetic disease characterized by congenital defects, bone marrow failure, and increased cancer risk. FA is associated with mutation in one of 24 genes. The protein products of these genes function cooperatively in the FA pathway to orchestrate the repair of DNA interstrand cross-links. Few model organisms exist for the study of FA. Seeking a model organism with a simpler version of the FA pathway, we searched the genome of the simple chordate Ciona intestinalis for homologs of the human FA-associated proteins. BLAST searches, sequence alignments, hydropathy comparisons, maximum likelihood phylogenetic analysis, and structural modeling were used to infer the likelihood of homology between C. intestinalis and human FA proteins. Our analysis indicates that C. intestinalis indeed has a simpler and potentially functional FA pathway. The C. intestinalis genome was searched for candidates for homology to 24 human FA and FA-associated proteins. Support was found for the existence of homologs for 13 of these 24 human genes in C. intestinalis. Members of each of the three commonly recognized FA gene functional groups were found. In group I, we identified homologs of FANCE, FANCL, FANCM, and UBE2T/FANCT. Both members of group II, FANCD2 and FANCI, have homologs in C. intestinalis. In group III, we found evidence for homologs of FANCJ, FANCO, FANCQ/ERCC4, FANCR/RAD51, and FANCS/BRCA1, as well as the FA-associated proteins ERCC1 and FAN1. Evidence was very weak for the existence of homologs in C. intestinalis for any other recognized FA genes. This work supports the notion that C. intestinalis, as a close relative of vertebrates, but having a much reduced complement of FA genes, offers a means of studying the function of certain FA proteins in a simpler pathway than that of vertebrate cells. PMID:27279728

  5. Ciona intestinalis as a Marine Model System to Study Some Key Developmental Genes Targeted by the Diatom-Derived Aldehyde Decadienal

    PubMed Central

    Lettieri, Anna; Esposito, Rosaria; Ianora, Adrianna; Spagnuolo, Antonietta

    2015-01-01

    The anti-proliferative effects of diatoms, described for the first time in copepods, have also been demonstrated in benthic invertebrates such as polychaetes, sea urchins and tunicates. In these organisms PUAs (polyunsaturated aldehydes) induce the disruption of gametogenesis, gamete functionality, fertilization, embryonic mitosis, and larval fitness and competence. These inhibitory effects are due to the PUAs, produced by diatoms in response to physical damage as occurs during copepod grazing. The cell targets of these compounds remain largely unknown. Here we identify some of the genes targeted by the diatom PUA 2-trans-4-trans-decadienal (DD) using the tunicate Ciona intestinalis. The tools, techniques and genomic resources available for Ciona, as well as the suitability of Ciona embryos for medium-to high-throughput strategies, are key to their employment as model organisms in different fields, including the investigation of toxic agents that could interfere with developmental processes. We demonstrate that DD can induce developmental aberrations in Ciona larvae in a dose-dependent manner. Moreover, through a preliminary analysis, DD is shown to affect the expression level of genes involved in stress response and developmental processes. PMID:25789602

  6. Urochordate Ascidians Possess a Single Isoform of Aurora Kinase That Localizes to the Midbody via TPX2 in Eggs and Cleavage Stage Embryos

    PubMed Central

    Hebras, Celine; McDougall, Alex

    2012-01-01

    Aurora kinases are key proteins found throughout the eukaryotes that control mitotic progression. Vertebrate Aurora-A and B kinases are thought to have evolved from a single Aurora-kinase isoform closest to that found in present day urochordates. In urochordate ascidians Aurora binds both TPX2 (a vertebrate AURKA partner) and INCENP (a vertebrate AURKB partner) and localizes to centrosomes and spindle microtubules as well as chromosomes and midbody during both meiosis and mitosis. Ascidian Aurora also displays this localization pattern during mitosis in echinoderms, strengthening the idea that non-vertebrate deuterostomes such as the urochordates and echinoderms possess a single form of Aurora kinase that has properties of vertebrate Aurora-kinase A and B. In the ascidian, TPX2 localizes to the centrosome and the spindle poles also as in vertebrates. However, we were surprised to find that TPX2 also localized strongly to the midbody in ascidian eggs and embryos. We thus examined more closely Aurora localization to the midbody by creating two separate point mutations of ascidian Aurora predicted to perturb binding to TPX2. Both forms of mutated Aurora behaved as predicted: neither localized to spindle poles where TPX2 is enriched. Interestingly, neither form of mutated Aurora localized to the midbody where TPX2 is also enriched, suggesting that ascidian Aurora midbody localization required TPX2 binding in ascidians. Functional analysis revealed that inhibition of Aurora kinase with a pharmacological inhibitor or with a dominant negative kinase dead form of Aurora caused cytokinesis failure and perturbed midbody formation during polar body extrusion. Our data support the view that vertebrate Aurora-A and B kinases evolved from a single non-vertebrate deuterostome ancestor. Moreover, since TPX2 localizes to the midbody in ascidian eggs and cleavage stage embryos it may be worthwhile re-assessing whether Aurora A kinase or TPX2 localize to the midbody in eggs and

  7. Cytotoxicity of the Ascidian Cystodytes dellechiajei Against Tumor Cells and Study of the Involvement of Associated Microbiota in the Production of Cytotoxic Compounds

    PubMed Central

    Martinez-García, Manuel; Diaz-Valdés, Marta; Ramos-Esplá, Alfonso; Salvador, Nélida; Lopez, Patricia; Larriba, Eduardo; Antón, Josefa

    2007-01-01

    Many cytotoxic compounds of therapeutic interest have been isolated from marine invertebrates, and some of them have been reported to be of microbial origin. Pyridoacridine alkaloids are the main compounds extracted from the ascidian Cystodytes dellechiajei. Here we describe the in vitro antiproliferative activity against different tumor cell lines of the ascidian extracts and provide some insights on the role of the microbial community associated with the tunicate in the production of these compounds. C. dellechiajei extracts showed remarkably high antiproliferative activity (IC50 ≤5 μg/mL) in human lung carcinoma A-549, colon adenocarcinoma H-116, pancreatic adenocarcinoma PSN-1 and breast carcinoma SKBR3 cell lines. Moreover, we found that the maximum activity was located in the tunic tissue of the colony, which harbours a microbial community. In order to ascertain the involvement of this community in the synthesis of the bioactive compounds different approachs that included culture and culture independent methods were carried out. We undertook a screening for antiproliferative activities of the bacterial isolates from the ascidian, as well as a comprative analysis of the cytotoxic activities and the microbial communities from two color morphs of the ascidian, green and blue. In addition, the changes of the antiproliferative activities and the composition of the microbial communities were studied from ascidians kept in aquaria and treated with antibiotics for one month. Our data obtained from the different experiments did not point out to bacteria as the source of the cytotoxic compounds, suggesting thus an ascidian origin. PMID:18463720

  8. Ultrastructures and classification of circulating hemocytes in 9 botryllid ascidians (chordata: ascidiacea).

    PubMed

    Hirose, Euichi; Shirae, Maki; Saito, Yasunori

    2003-05-01

    Ultrastructures of circulating hemocytes were studied in 9 botryllid ascidians. The hemocytes are classified into five types: hemoblasts, phagocytes, granulocytes, morula cells, and pigment cells. These five types are always found in the 9 species. They should represent the major hemocyte types of the circulating cells in the blood. Hemoblasts are small hemocytes having a high nucleus/cytoplasm ratio. There are few granular or vacuolar inclusions in the cytoplasm. Phagocytes have phagocytic activity and their shape is variable depending on the amount of engulfed materials. In granulocytes, shape and size of granules are different among the species. Morula cells are characterized by several vacuoles filled with electron dense materials. In pigment cells, the bulk of the cytoplasm is occupied by one or a few vacuoles containing pigment granules. We also described some other hemocyte types found in particular species. Furthermore, we encountered free oocytes circulating in the blood in two species, Botryllus primigenus and Botrylloides lentus.

  9. Azumiobodo hoyamushi, the kinetoplastid causing soft tunic syndrome in ascidians, may invade through the siphon wall.

    PubMed

    Hirose, Euichi; Kumagai, Akira; Nawata, Akatsuki; Kitamura, Shin-Ichi

    2014-07-01

    The infectious kinetoplastid Azumiobodo hoyamushi causes 'soft tunic syndrome', a serious problem in aquaculture of the edible ascidian Halocynthia roretzi. Infection tests using diseased tunics demonstrated that juvenile (0.8 yr old) individuals never developed soft tunic syndrome, but all individuals in the other age groups (1.8, 2.8, and 3.8 yr old) showed the disease symptoms. In the infection tests, tunic softening was first observed at the tunic around siphons. Based on ultrastructural observation of the inner wall of the branchial siphon, the tunic lining the inner wall in juveniles (0.5 yr old) was completely covered with cuticle, which had a dense structure to prevent bacterial and protist invasion. In contrast, the tunic was often partly damaged and not covered with cuticle in healthy adults (≥2.5 yr old). The damaged tunic in the siphon wall could be an entrance for A. hoyamushi into the tunic of adult hosts.

  10. [Distribution and abundance of the ascidian Ecteinascidia turbinata (Ascidiacea: Perophoridae) in Cuba].

    PubMed

    Hernández-Zanuy, Aida; Carballo, José Luis; García-Cagide, Alida; Naranjo, Santiago; Esquivel, Macario

    2007-03-01

    Permanently submerged mangrove roots (Rhizophora mangle) are the main habitat of the ascidian Ecteinascidia turbinata in Cuba. It was occasionally found on black coral (Antiphates caribeana) between 22 and 38 meters deep. This species exhibits a wide distribution in all the mangrove keys surrounding the Island of Cuba but does not occur in riparian or fringing mangroves. Populations of this species are abundant in Cuba: in 75% of the 58 localities sampled the species was present and in 57% more than 50% of the roots held at least one colony. The highest colony densities were found in the northern coast of Pinar del Rio province with values near one colony per lineal meter of mangrove root. We found the highest density (1.46 col/m) and greatest biomass at Jutías Key, with values between 25 and 660 g/m. The average of wet biomass in the studied mangroves was 73.63 g/m. PMID:18457133

  11. 3-bromohomofascaplysin A, a fascaplysin analogue from a Fijian Didemnum sp. ascidian.

    PubMed

    Lu, Zhenyu; Ding, Yuanqing; Li, Xing-Cong; Djigbenou, Daignon R; Grimberg, Brian T; Ferreira, Daneel; Ireland, Chris M; Van Wagoner, Ryan M

    2011-11-15

    A new fascaplysin analogue, 3-bromohomofascaplysin A (1), along with two known analogues, homofascaplysin A (2) and fascaplysin (3), were isolated from a Fijian Didemnum sp. ascidian. The absolute configurations of 3-bromohomofascaplysin A (1) and homofascaplysin A (2) were determined via experimental and theoretically calculated ECD spectra. The differential activities of 1-3 against different blood-borne life stages of the malaria pathogen Plasmodium falciparum were assessed. Homofascaplysin A (2) displayed an IC(50) of 0.55±0.11 nM against ring stage parasites and 105±38 nM against all live parasites. Given the stronger resistance of ring stage parasites against most current antimalarials relative to the other blood stages, homofascaplysin A (2) represents a promising agent for treatment of drug resistant malaria.

  12. 3-Bromohomofascaplysin A, a fascaplysin analogue from a Fijian Didemnum sp. ascidian

    PubMed Central

    Lu, Zhenyu; Ding, Yuanqing; Li, Xing-Cong; Djigbenou, Daignon R.; Grimberg, Brian T.; Ferreira, Daneel; Ireland, Chris M.; Van Wagoner, Ryan M.

    2011-01-01

    A new fascaplysin analogue, 3-bromohomofascaplysin A (1), along with two known analogues, homofascaplysin A (2) and fascaplysin (3), were isolated from a Fijian Didemnum sp. ascidian. The absolute configurations of 3-bromohomofascaplysin A (1) and homofascaplysin A (2) were determined via experimental and theoretically calculated ECD spectra. The differential activities of 1–3 against different blood-borne life stages of the malaria pathogen Plasmodium falciparum were assessed. Homofascaplysin A (2) displayed an IC50 of 0.55 ± 0.11 nM against ring stage parasites and 105 ± 38 nM against all live parasites. Given the stronger resistance of ring stage parasites against most current antimalarials relative to the other blood stages, homofascaplysin A (2) represents a promising agent for treatment of drug resistant malaria. PMID:21696970

  13. New GlcNAc/GalNAc-specific lectin from the ascidian Didemnum ternatanum.

    PubMed

    Molchanova, Valentina; Chikalovets, Irina; Li, Wei; Kobelev, Stanislav; Kozyrevskaya, Svetlana; Bogdanovich, Raisa; Howard, Eric; Belogortseva, Natalia

    2005-05-25

    Previously we isolated GlcNAc-specific lectin (DTL) from the ascidian Didemnum ternatanum by affinity chromatography on cross-linked ovalbumin. Here we report the purification and characterization of new D-GlcNAc/D-GalNAc-specific lectin DTL-A from the same ascidian. This lectin was isolated from non-bound cross-linked ovalbumin fraction and further was purified by gel filtration on Sepharose CL-4B, affinity chromatography on GlcNAc-agarose and gel filtration on Superdex 200. SDS-polyacrylamide gel electrophoresis and gel filtration of purified lectin on Sepharose CL-4B indicates that it exists as large aggregates in the native state. Investigations of the carbohydrate specificity of DTL-A by enzyme-linked lectin assay suggest the multi-specificity of this lectin. DTL-A binds BSM, asialo-BSM as well as heparin and dextran sulfate. The binding of DTL-A to BSM was inhibited by monosaccharides D-GlcNAc and D-GalNAc, their alpha- but not beta-anomers. Among polysaccharides and glycoconjugates, DTL-A binding to BSM was effectively inhibited by BSM, asialo-BSM, pronase-treated BSM and synthetic alpha-D-GalNAc-PAA. Fetuin and asialofetuin showed a much lower inhibitory potency, heparin and dextran sulfate were noninhibitory. On the other hand, DTL-A binding to heparin was effectively inhibited by dextran sulfate, fucoidan, whereas BSM showed insignificantly inhibitory effect. DTL-A binding to heparin was not inhibited by D-GlcNAc and D-GalNAc.

  14. Microenvironmental Ecology of the Chlorophyll b-Containing Symbiotic Cyanobacterium Prochloron in the Didemnid Ascidian Lissoclinum patella

    PubMed Central

    Kühl, Michael; Behrendt, Lars; Trampe, Erik; Qvortrup, Klaus; Schreiber, Ulrich; Borisov, Sergey M.; Klimant, Ingo; Larkum, Anthony W. D.

    2012-01-01

    The discovery of the cyanobacterium Prochloron was the first finding of a bacterial oxyphototroph with chlorophyll (Chl) b, in addition to Chl a. It was first described as Prochloron didemni but a number of clades have since been described. Prochloron is a conspicuously large (7–25 μm) unicellular cyanobacterium living in a symbiotic relationship, primarily with (sub-) tropical didemnid ascidians; it has resisted numerous cultivation attempts and appears truly obligatory symbiotic. Recently, a Prochloron draft genome was published, revealing no lack of metabolic genes that could explain the apparent inability to reproduce and sustain photosynthesis in a free-living stage. Possibly, the unsuccessful cultivation is partly due to a lack of knowledge about the microenvironmental conditions and ecophysiology of Prochloron in its natural habitat. We used microsensors, variable chlorophyll fluorescence imaging and imaging of O2 and pH to obtain a detailed insight to the microenvironmental ecology and photobiology of Prochloron in hospite in the didemnid ascidian Lissoclinum patella. The microenvironment within ascidians is characterized by steep gradients of light and chemical parameters that change rapidly with varying irradiances. The interior zone of the ascidians harboring Prochloron thus became anoxic and acidic within a few minutes of darkness, while the same zone exhibited O2 super-saturation and strongly alkaline pH after a few minutes of illumination. Photosynthesis showed lack of photoinhibition even at high irradiances equivalent to full sunlight, and photosynthesis recovered rapidly after periods of anoxia. We discuss these new insights on the ecological niche of Prochloron and possible interactions with its host and other microbes in light of its recently published genome and a recent study of the overall microbial diversity and metagenome of L. patella. PMID:23226144

  15. Screening for negative effects of candidate ascidian antifoulant compounds on a target aquaculture species, Perna canaliculus Gmelin.

    PubMed

    Cahill, Patrick Louis; Heasman, Kevin; Hickey, Anthony; Mountfort, Douglas; Jeffs, Andrew; Kuhajek, Jeannie

    2013-01-01

    The natural chemical compounds radicicol, polygodial and ubiquinone-10 (Q10) have previously been identified as inhibitors of metamorphosis in ascidian larvae. Accordingly, they have potential as a specific remedy for the costly problem of fouling ascidians in bivalve aquaculture. In this study, these compounds were screened for their effects on the physiological health of an aquaculture species, the green-lipped mussel, Perna canaliculus Gmelin, at or above the 99% effective dose (IC(99)) in ascidians. Three physiological biomarkers of mussel health were screened: growth (increases in shell height and wet weight), condition (condition index) and mitochondrial respirational function (Complex I-mediated respiration, Complex II-mediated respiration, maximum uncoupled respiration, leak respiration, respiratory control ratios and phosphorylation system control ratios). While polygodial and Q10 had no effect on mussel growth or the condition index, radicicol retarded growth and decreased the condition index. Mitochondrial respirational function was unaffected by radicicol and polygodial. Conversely, Q10 enhanced Complex I-mediated respiration, highlighting the fundamental role of this compound in the electron transport system. The present study suggests that polygodial and Q10 do not negatively affect the physiological health of P. canaliculus at the IC(99) in ascidians, while radicicol is toxic. Moreover, Q10 is of benefit in biomedical settings as a cellular antioxidant and therefore may also benefit P. canaliculus. Accordingly, polygodial and Q10 should be progressed to the next stage of testing where possible negative effects on bivalves will be further explored, followed by development of application techniques and testing in a laboratory and aquaculture setting.

  16. Screening for negative effects of candidate ascidian antifoulant compounds on a target aquaculture species, Perna canaliculus Gmelin.

    PubMed

    Cahill, Patrick Louis; Heasman, Kevin; Hickey, Anthony; Mountfort, Douglas; Jeffs, Andrew; Kuhajek, Jeannie

    2013-01-01

    The natural chemical compounds radicicol, polygodial and ubiquinone-10 (Q10) have previously been identified as inhibitors of metamorphosis in ascidian larvae. Accordingly, they have potential as a specific remedy for the costly problem of fouling ascidians in bivalve aquaculture. In this study, these compounds were screened for their effects on the physiological health of an aquaculture species, the green-lipped mussel, Perna canaliculus Gmelin, at or above the 99% effective dose (IC(99)) in ascidians. Three physiological biomarkers of mussel health were screened: growth (increases in shell height and wet weight), condition (condition index) and mitochondrial respirational function (Complex I-mediated respiration, Complex II-mediated respiration, maximum uncoupled respiration, leak respiration, respiratory control ratios and phosphorylation system control ratios). While polygodial and Q10 had no effect on mussel growth or the condition index, radicicol retarded growth and decreased the condition index. Mitochondrial respirational function was unaffected by radicicol and polygodial. Conversely, Q10 enhanced Complex I-mediated respiration, highlighting the fundamental role of this compound in the electron transport system. The present study suggests that polygodial and Q10 do not negatively affect the physiological health of P. canaliculus at the IC(99) in ascidians, while radicicol is toxic. Moreover, Q10 is of benefit in biomedical settings as a cellular antioxidant and therefore may also benefit P. canaliculus. Accordingly, polygodial and Q10 should be progressed to the next stage of testing where possible negative effects on bivalves will be further explored, followed by development of application techniques and testing in a laboratory and aquaculture setting. PMID:23194394

  17. Programmed cell death in vegetative development: apoptosis during the colonial life cycle of the ascidian Botryllus schlosseri.

    PubMed

    Tiozzo, S; Ballarin, L; Burighel, P; Zaniolo, G

    2006-06-01

    Programmed cell death (PCD) by apoptosis is a physiological mechanism by which cells are eliminated during embryonic and post-embryonic stages of animal life cycle. During asexual reproduction, the zooids of colonial ascidians originate from an assorted cell population instead of a single zygote, so that we assume that regulation of the equilibrium among proliferation, differentiation and cell death may follow different pathways in comparison to the embryonic development. Here we investigate the presence of apoptotic events throughout the blastogenetic life cycle of the colonial ascidian Botryllus schlosseri, by means of terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL) coupled with histochemical and electron microscopy techniques. The occurrence of low levels of morphogenetic cell death suggests that, in contrast to what happens during sexual development (embryogenesis and metamorphosis), apoptosis does not play a pivotal role during asexual propagation in botryllid ascidian. Nevertheless, PCD emerges as a key force to regulate homeostasis in adult zooids and to shape and modulate the growth of the whole colony.

  18. Studies on the seasonal variations in the proximate composition of ascidians from the Palk Bay, Southeast coast of India

    PubMed Central

    Ananthan, G; Karthikeyan, MM; Selva, Prabhu A; Raghunathan, C

    2012-01-01

    Objective To investigate the seasonal fluctuations of the proximate composition of the ascidians muscle. Methods The moisture content was estimated by drying 1 g of fresh tissue at a constant temperature at 105 °C for 24 h.The loss of weight was taken as moisture content. The total protein was estimated using the Biuret method. The total carbohydrate in dried sample was estimated spectrophotometrically following the phenol- sulphuric acid method. The lipid in the dried sample tissue was gravimetrically estimated following the chloroform-methanol mixture method. Ash content was determined gravimetrically by incinerating 1 g dried sample in muffle furnace at about 550 °C for 6 h and results are expressed in percentage. Results It was found very difficult to compare the monthly variations, as all the ten species, exhibited wide fluctuations in their proximate compositions. For the sake of convenience, average seasonal values were calculated by summing the monthly values. Conclusions The proximate composition of the 10 commonly available ascidians showed high nutritive value and hence these groups especially solitary ascidians can be recommended for human consumption in terms of pickles, soup, curry and others after ensuring the safety of consumers. PMID:23569849

  19. Cellulose is not degraded in the tunic of the edible ascidian Halocynthia roretzi contracting soft tunic syndrome.

    PubMed

    Kimura, Satoshi; Nakayama, Kei; Wada, Masahisa; Kim, Ung-Jin; Azumi, Kaoru; Ojima, Takao; Nozawa, Akino; Kitamura, Shin-Ichi; Hirose, Euichi

    2015-10-16

    Soft tunic syndrome is a fatal disease in the edible ascidian Halocynthia roretzi, causing serious damage to ascidian aquaculture in Korea and Japan. In diseased individuals, the tunic, an integumentary extracellular matrix of ascidians, softens and eventually tears. This is an infectious disease caused by the kinetoplastid flagellate Azumiobodo hoyamushi. However, the mechanism of tunic softening remains unknown. Because cellulose fibrils are the main component of the tunic, we compared the contents and structures of cellulose in healthy and diseased tunics by means of biochemical quantification and X-ray diffractometry. Unexpectedly, the cellulose contents and structures of cellulose microfibrils were almost the same regardless of the presence or absence of the disease. Therefore, it is unlikely that thinning of the microfibrils occurred in the softened tunic, because digestion should have resulted in decreases in crystallinity index and crystallite size. Moreover, cellulase was not detected in pure cultures of A. hoyamushi in biochemical and expressed sequence tag analyses. These results indicate that cellulose degradation does not occur in the softened tunic. PMID:26480917

  20. Molecular basis of canalization in an ascidian species complex adapted to different thermal conditions

    PubMed Central

    Sato, Atsuko; Kawashima, Takeshi; Fujie, Manabu; Hughes, Samantha; Satoh, Noriyuki; Shimeld, Sebastian M.

    2015-01-01

    Canalization is a result of intrinsic developmental buffering that ensures phenotypic robustness under genetic variation and environmental perturbation. As a consequence, animal phenotypes are remarkably consistent within a species under a wide range of conditions, a property that seems contradictory to evolutionary change. Study of laboratory model species has uncovered several possible canalization mechanisms, however, we still do not understand how the level of buffering is controlled in natural populations. We exploit wild populations of the marine chordate Ciona intestinalis to show that levels of buffering are maternally inherited. Comparative transcriptomics show expression levels of genes encoding canonical chaperones such as Hsp70 and Hsp90 do not correlate with buffering. However the expression of genes encoding endoplasmic reticulum (ER) chaperones does correlate. We also show that ER chaperone genes are widely conserved amongst animals. Contrary to previous beliefs that expression level of Heat Shock Proteins (HSPs) can be used as a measurement of buffering levels, we propose that ER associated chaperones comprise a cellular basis for canalization. ER chaperones have been neglected by the fields of development, evolution and ecology, but their study will enhance understanding of both our evolutionary past and the impact of global environmental change. PMID:26577490

  1. A Maternal System Initiating the Zygotic Developmental Program through Combinatorial Repression in the Ascidian Embryo

    PubMed Central

    Oda-Ishii, Izumi; Kubo, Atsushi; Kari, Willi; Suzuki, Nobuhiro; Rothbächer, Ute

    2016-01-01

    Maternal factors initiate the zygotic developmental program in animal embryos. In embryos of the chordate, Ciona intestinalis, three maternal factors—Gata.a, β-catenin, and Zic-r.a—are required to establish three domains of gene expression at the 16-cell stage; the animal hemisphere, vegetal hemisphere, and posterior vegetal domains. Here, we show how the maternal factors establish these domains. First, only β-catenin and its effector transcription factor, Tcf7, are required to establish the vegetal hemisphere domain. Second, genes specifically expressed in the posterior vegetal domain have additional repressive cis-elements that antagonize the activity of β-catenin/Tcf7. This antagonizing activity is suppressed by Zic-r.a, which is specifically localized in the posterior vegetal domain and binds to DNA indirectly through the interaction with Tcf7. Third, Gata.a directs specific gene expression in the animal hemisphere domain, because β-catenin/Tcf7 weakens the Gata.a-binding activity for target sites through a physical interaction in the vegetal cells. Thus, repressive regulation through protein-protein interactions among the maternal transcription factors is essential to establish the first distinct domains of gene expression in the chordate embryo. PMID:27152625

  2. Molecular basis of canalization in an ascidian species complex adapted to different thermal conditions.

    PubMed

    Sato, Atsuko; Kawashima, Takeshi; Fujie, Manabu; Hughes, Samantha; Satoh, Noriyuki; Shimeld, Sebastian M

    2015-01-01

    Canalization is a result of intrinsic developmental buffering that ensures phenotypic robustness under genetic variation and environmental perturbation. As a consequence, animal phenotypes are remarkably consistent within a species under a wide range of conditions, a property that seems contradictory to evolutionary change. Study of laboratory model species has uncovered several possible canalization mechanisms, however, we still do not understand how the level of buffering is controlled in natural populations. We exploit wild populations of the marine chordate Ciona intestinalis to show that levels of buffering are maternally inherited. Comparative transcriptomics show expression levels of genes encoding canonical chaperones such as Hsp70 and Hsp90 do not correlate with buffering. However the expression of genes encoding endoplasmic reticulum (ER) chaperones does correlate. We also show that ER chaperone genes are widely conserved amongst animals. Contrary to previous beliefs that expression level of Heat Shock Proteins (HSPs) can be used as a measurement of buffering levels, we propose that ER associated chaperones comprise a cellular basis for canalization. ER chaperones have been neglected by the fields of development, evolution and ecology, but their study will enhance understanding of both our evolutionary past and the impact of global environmental change. PMID:26577490

  3. Ecological observations on the colonial ascidian Didemnum sp. in a New England tide pool habitat

    USGS Publications Warehouse

    Valentine, P.C.; Carman, M.R.; Blackwood, D.S.; Heffron, E.J.

    2007-01-01

    The colonial ascidian Didemnum sp. has colonized northwestern Atlantic coastal habitats from southern Long Island, New York, to Eastport, Maine. It is also present in offshore habitats of the Georges Bank fishing grounds. It threatens to alter fisheries habitats and shellfish aquacultures. Observations in a tide pool at Sandwich, MA from December 2003 to February 2006 show that Didemnum sp. tolerates water temperatures ranging from ≤ 1 to > 24 °C, with daily changes of up to 11 °C. It attaches to pebbles, cobbles, and boulders, and it overgrows other tunicates, seaweeds, sponges, and bivalves. From May to mid July, colonies appear as small patches on the bottoms of rocks. Colonies grow rapidly from July to September, with some growth into December, and they range in color from pink to pale yellow to pale orange. Colony health declines from October through April, presumably in response to changes in water temperatures, and this degenerative process is manifested by color changes, by the appearance of small dark brown spots that represent clumps of fecal pellets in the colony, by scavenging by periwinkles, and by a peeling-away of colonies from the sides of cobbles and boulders. At Sandwich, colonies died that were exposed to air at low tide. The species does not exhibit this seasonal cycle of growth and decline in subtidal habitats (40–65 m) on the Georges Bank fishing grounds where the daily climate is relatively stable and annual water temperatures range from 4 to 15 °C. Experiments in the tide pool with small colony fragments (5 to 9 cm2) show they re-attach and grow rapidly by asexual budding, increasing in size 6- to 11-fold in the first 15 days. Didemnum sp. at Sandwich has no known predators except for common periwinkles (Littorina littorea) that graze on degenerating colonies in the October to April time period and whenever colonies are stressed by desiccation. The tendencies of the ascidian (1) to attach to firm substrates, (2) to rapidly overgrow

  4. Localization of CiCBR in the invertebrate chordate Ciona intestinalis: evidence of an ancient role for cannabinoid receptors as axonal regulators of neuronal signalling.

    PubMed

    Egertová, Michaela; Elphick, Maurice R

    2007-06-01

    CiCBR is a G-protein-coupled receptor in the sea-squirt Ciona intestinalis and the first ortholog of vertebrate CB(1) and CB(2) cannabinoid receptors to be identified in an invertebrate (Elphick et al. [2003] Gene 302:95-101). Here we have used Western blotting and immunocytochemistry to examine expression of CiCBR in adult Ciona, employing novel antibodies to the C-terminal tail of CiCBR. Consistent with the expected mass for CiCBR, a approximately 47-kDa band was detected in Ciona membranes, and immunocytochemical analysis of serial sections of Ciona revealed intense immunoreactivity in the cerebral ganglion localised in a dense meshwork of fibers in the neuropile. Accordingly, Western blot analysis of neural complex homogenates revealed the presence of a approximately 47-kDa band. CiCBR immunoreactivity was also observed in axons exiting the ganglion in the anterior and posterior nerves, and analysis of whole-mount preparations revealed that these axons project over the interior surface of the oral and atrial siphons. Isolated CiCBR-immunoreactive axons not associated with the anterior and posterior nerves were observed projecting through the cortical layer of the cerebral ganglion. Central and peripheral CiCBR-immunoreactive fibers were studded with intensely stained varicosities, indicative of a role for CiCBR in regulation of axonal release of neurotransmitters, neuromodulators, or neurohormones. Collectively, our data suggest that the well-established role that the CB(1) receptor has as an axonal regulator of neurotransmitter release in mammals may have originated with ancestral-type cannabinoid receptors in invertebrate chordates before the emergence of CB(1)- and CB(2)-type receptors in vertebrates. PMID:17428001

  5. Chemotactic response with a constant delay-time mechanism in Ciona spermatozoa revealed by a high time resolution analysis of flagellar motility.

    PubMed

    Miyashiro, Daisuke; Shiba, Kogiku; Miyashita, Tahahiro; Baba, Shoji A; Yoshida, Manabu; Kamimura, Shinji

    2015-01-01

    During their chemotactic swimming toward eggs, sperm cells detect their species-specific chemoattractant and sense concentration gradients by unknown mechanisms. After sensing the attractant, sperm cells commonly demonstrate a series of responses involving different swimming patterns by changing flagellar beats, gradually approaching a swimming path toward the eggs, which is the source of chemoattractants. Shiba et al. observed a rapid increase in intracellular Ca(2+) concentrations in Ciona spermatozoa after sensing chemoattractants; however, the biochemical processes occurring inside the sperm cells are unclear. In the present study, we focused on the timing and sensing mechanism of chemical signal detection in Ciona. One of the most crucial problems to be solved is defining the initial epoch of chemotactic responses. We adopted a high rate of video recording (600 Hz) for detailed analysis of sperm motion and a novel method for detecting subtle signs of beat forms and moving paths of sperm heads. From these analyses, we estimated a virtual sensing point of the attractant before initiation of motility responses and found that the time delay from sensing to motility responses was almost constant. To evaluate the efficiency of this constant delay model, we performed computer simulation of chemotactic behaviors of Ciona spermatozoa. PMID:25572419

  6. Complete DNA sequence of the mitochondrial genome of the ascidian Halocynthia roretzi (Chordata, Urochordata).

    PubMed

    Yokobori, S i; Ueda, T; Feldmaier-Fuchs, G; Pääbo, S; Ueshima, R; Kondow, A; Nishikawa, K; Watanabe, K

    1999-12-01

    The complete nucleotide sequence of the 14,771-bp-long mitochondrial (mt) DNA of a urochordate (Chordata)-the ascidian Halocynthia roretzi-was determined. All the Halocynthia mt-genes were found to be located on a single strand, which is rich in T and G rather than in A and C. Like nematode and Mytilus edulis mtDNAs, that of Halocynthia encodes no ATP synthetase subunit 8 gene. However, it does encode an additional tRNA gene for glycine (anticodon TCT) that enables Halocynthia mitochondria to use AGA and AGG codons for glycine. The mtDNA carries an unusual tRNA(Met) gene with a TAT anticodon instead of the usual tRNA(Met)(CAT) gene. As in other metazoan mtDNAs, there is not any long noncoding region. The gene order of Halocynthia mtDNA is completely different from that of vertebrate mtDNAs except for tRNA(His)-tRNA(Ser)(GCU), suggesting that evolutionary change in the mt-gene structure is much accelerated in the urochordate line compared with that in vertebrates. The amino acid sequences of Halocynthia mt-proteins deduced from their gene sequences are quite different from those in other metazoans, indicating that the substitution rate in Halocynthia mt-protein genes is also accelerated.

  7. Recurrent phagocytosis-induced apoptosis in the cyclical generation change of the compound ascidian Botryllus schlosseri.

    PubMed

    Franchi, Nicola; Ballin, Francesca; Manni, Lucia; Schiavon, Filippo; Basso, Giuseppe; Ballarin, Loriano

    2016-09-01

    Colonies of the marine, filter-feeding ascidian Botryllus schlosseri undergo cyclical generation changes or takeovers. These events are characterised by the progressive resorption of adult zooids and their replacement by their buds that grow to adult size, open their siphons and start filtering. During the take-over, tissues of adult zooids undergo extensive apoptosis; circulating, spreading phagocytes enter the effete tissues, ingest dying cells acquiring a giant size and a round morphology. Then, phagocytes re-enter the circulation where they represent a considerable fraction (more than 20%) of circulating haemocytes. In this study, we evidence that most of these circulating phagocytes show morphological and biochemical signs of apoptosis. Accordingly, these phagocytes express transcripts of orthologues of the apoptosis-related genes Bax, AIF1 and PARP1. Electron microscopy shows that giant phagocytes contain apoptotic phagocytes inside their own phagocytic vacuole. The transcript of the orthologues of the anti-apoptotic gene IAP7 was detected only in spreading phagocytes, mostly abundant in phases far from the take-over. Therefore, the presented data suggest that, at take-over, phagocytes undergo phagocytosis-induced apoptosis (PIA). In mammals, PIA is assumed to be a process assuring the killing and the complete elimination of microbes, by promoting the disposal of terminally differentiated phagocytes and the resolution of infection. In B. schlosseri, PIA assumes a so far undescribed role, being required for the control of asexual development and colony homeostasis.

  8. Immunotoxicity in ascidians: antifouling compounds alternative to organotins-IV. The case of zinc pyrithione.

    PubMed

    Cima, Francesca; Ballarin, Loriano

    2015-03-01

    New biocides such as the organometallic compound zinc pyrithione (ZnP) have been massively introduced by many countries in formulations of antifouling paints following the ban on tributyltin (TBT). The effects of sublethal concentrations (LC50=82.5 μM, i.e., 26.2 mg/l) on cultured haemocytes of the ascidian Botryllus schlosseri have been investigated and compared with TBT. The percentage of haemocytes with amoeboid morphology and containing phagocytised yeast cells were significantly (p<0.05) reduced after exposure to 0.1 (31.7 μg/l) and 0.5 μM (158 μg/l), respectively. An antagonistic interaction in inducing cytoskeletal alterations was observed when ZnP and TBT were co-present in the exposure medium. ZnP affected only the actin component. As caused by TBT, ZnP induced apoptosis and inhibited both oxidative phosphorylation and lysosomal activities. In contrast to the case of TBT, a decrement in Ca(2+)-ATPase activity and a decrease in cytosolic Ca(2+) were detected after incubation at the highest concentration (1 μM, i.e., 317.7 μg/l) used. In comparison with other antifouling compounds, ZnP shows as much toxicity as TBT to cultured haemocytes at extremely low concentrations interfering with fundamental cell activities. PMID:25576186

  9. Multilocus genetic analyses differentiate between widespread and spatially restricted cryptic species in a model ascidian

    PubMed Central

    Bock, Dan G.; MacIsaac, Hugh J.; Cristescu, Melania E.

    2012-01-01

    Elucidating the factors that shape species distributions has long been a fundamental goal in ecology and evolutionary biology. In spite of significant theoretical advancements, empirical studies of range limits have lagged behind. Specifically, little is known about how the attributes that allow species to expand their ranges and become widespread vary across phylogenies. Here, we studied the ascidian Botryllus schlosseri, a worldwide invasive species that is also characterized by marked genetic subdivision. Our study includes phylogenetic and population genetic data based on mitochondrial and nuclear genes, as well as polymorphic microsatellites for B. schlosseri colonies sampled from the southern and northern coasts of Europe and the eastern and western coasts of North America. We demonstrate that this well-known model organism comprises three highly divergent and probably reproductively isolated cryptic species (A, D and E), with two more (B and C) being suggested by data retrieved from GenBank. Among these, species A, recovered in all of the surveyed regions, is by far the most common and widespread. By contrast, species B–E, occurring mostly in sites from northern Europe, are considerably more geographically restricted. These findings, along with inferences made on transport opportunity, suggest that divergent evolutionary histories promoted differences in invasive potential between B. schlosseri sibling species, indicating that attributes that facilitate dramatic shifts in range limits can evolve more easily and frequently than previously thought. We propose environmental disturbance as a selective force that could have shaped the evolution of invasiveness in the B. schlosseri complex. PMID:22319123

  10. Transcriptional activity and expression of liver X receptor in the ascidian Halocynthia roretzi.

    PubMed

    Raslan, Ahmed Ahmed; Lee, Jung Hwan; Shin, Jihye; Shin, Yun Kyung; Sohn, Young Chang

    2013-09-01

    Liver X receptors, LXRs, are ligand-activated transcription factors that belong to the group H nuclear receptor (NR) superfamily. In this study, an LXR (HrLXR) cDNA was cloned from the ascidian Halocynthia roretzi hepatopancreas and characterized to examine the functional conservation of ancestral LXRs in chordates. A phylogenetic analysis of HrLXR showed that it belongs to the tunicate (urochordate) LXR subgroup, which is distinct from vertebrate LXRs. Quantitative real-time PCR analysis revealed that HrLXR mRNA was expressed predominantly in the gills, and highly expressed in unfertilized eggs followed by decrease at later embryonic and larval stages. Unexpectedly, HrLXR was not activated by GW3965, whereas a synthetic ligand for a farnesoid X receptor, GW4064, activated HrLXR. This activation was abolished by the deletion of 51 amino acids from the N-terminus. In a mammalian two-hybrid system, HrLXR interacted with HrRXR in the presence of GW4064 or 9-cis retinoic acid. The injection of GW3965 and GW4064 in vivo increased the ATPbinding cassette sub-family G member 4 and HrLXR mRNA levels in the hepatopancreas and gills. These results suggest that the mRNA expression and transcriptional properties of HrLXR are different from those of vertebrate LXRs, although HrLXR is likely responsive to the related NR ligand, GW4064.

  11. Global Phylogeography of the Widely Introduced North West Pacific Ascidian Styela clava

    PubMed Central

    Goldstien, Sharyn J.; Dupont, Lise; Viard, Frédérique; Hallas, Paul J.; Nishikawa, Teruaki; Schiel, David R.; Gemmell, Neil J.; Bishop, John D. D.

    2011-01-01

    The solitary ascidian Styela clava Herdman, 1882 is considered to be native to Japan, Korea, northern China and the Russian Federation in the NW Pacific, but it has spread globally over the last 80 years and is now established as an introduced species on the east and west coasts of North America, Europe, Australia and New Zealand. In eastern Canada it reaches sufficient density to be a serious pest to aquaculture concerns. We sequenced a fragment of the cytochrome oxidase subunit I mitochondrial gene (COI) from a total of 554 individuals to examine the genetic relationships of 20 S. clava populations sampled throughout the introduced and native ranges, in order to investigate invasive population characteristics. The data presented here show a moderate level of genetic diversity throughout the northern hemisphere. The southern hemisphere (particularly New Zealand) displays a greater amount of haplotype and nucleotide diversity in comparison. This species, like many other invasive species, shows a range of genetic diversities among introduced populations independent of the age of incursion. The successful establishment of this species appears to be associated with multiple incursions in many locations, while other locations appear to have experienced rapid expansion from a potentially small population with reduced genetic diversity. These contrasting patterns create difficulties when attempting to manage and mitigate a species that continues to spread among ports and marinas around the world. PMID:21364988

  12. The activation wave of calcium in the ascidian egg and its role in ooplasmic segregation

    PubMed Central

    1990-01-01

    We have studied egg activation and ooplasmic segregation in the ascidian Phallusia mammillata using an imaging system that let us simultaneously monitor egg morphology and calcium-dependent aequorin luminescence. After insemination, a wave of highly elevated free calcium crosses the egg with a peak velocity of 8-9 microns/s. A similar wave is seen in egg fertilized in the absence of external calcium. Artificial activation via incubation with WGA also results in a calcium wave, albeit with different temporal and spatial characteristics than in sperm-activated eggs. In eggs in which movement of the sperm nucleus after entry is blocked with cytochalasin D, the sperm aster is formed at the site where the calcium wave had previously started. This indicates that the calcium wave starts where the sperm enters. In 70% of the eggs, the calcium wave starts in the animal hemisphere, which confirms previous observations that there is a preference for sperm to enter this part of the egg (Speksnijder, J. E., L. F. Jaffe, and C. Sardet. 1989. Dev. Biol. 133:180-184). About 30-40 s after the calcium wave starts, a slower (1.4 microns/s) wave of cortical contraction starts near the animal pole. It carries the subcortical cytoplasm to a contraction pole, which forms away from the side of sperm entry and up to 50 degrees away from the vegetal pole. We propose that the point of sperm entry may affect the direction of ooplasmic segregation by causing it to tilt away from the vegetal pole, presumably via some action of the calcium wave. PMID:2335565

  13. The activation wave of calcium in the ascidian egg and its role in ooplasmic segregation.

    PubMed

    Speksnijder, J E; Sardet, C; Jaffe, L F

    1990-05-01

    We have studied egg activation and ooplasmic segregation in the ascidian Phallusia mammillata using an imaging system that let us simultaneously monitor egg morphology and calcium-dependent aequorin luminescence. After insemination, a wave of highly elevated free calcium crosses the egg with a peak velocity of 8-9 microns/s. A similar wave is seen in egg fertilized in the absence of external calcium. Artificial activation via incubation with WGA also results in a calcium wave, albeit with different temporal and spatial characteristics than in sperm-activated eggs. In eggs in which movement of the sperm nucleus after entry is blocked with cytochalasin D, the sperm aster is formed at the site where the calcium wave had previously started. This indicates that the calcium wave starts where the sperm enters. In 70% of the eggs, the calcium wave starts in the animal hemisphere, which confirms previous observations that there is a preference for sperm to enter this part of the egg (Speksnijder, J. E., L. F. Jaffe, and C. Sardet. 1989. Dev. Biol. 133:180-184). About 30-40 s after the calcium wave starts, a slower (1.4 microns/s) wave of cortical contraction starts near the animal pole. It carries the subcortical cytoplasm to a contraction pole, which forms away from the side of sperm entry and up to 50 degrees away from the vegetal pole. We propose that the point of sperm entry may affect the direction of ooplasmic segregation by causing it to tilt away from the vegetal pole, presumably via some action of the calcium wave.

  14. Biology of the invasive ascidian Ascidiella aspersa in its native habitat: Reproductive patterns and parasite load

    NASA Astrophysics Data System (ADS)

    Lynch, Sharon A.; Darmody, Grainne; O'Dwyer, Katie; Gallagher, Mary Catherine; Nolan, Sinead; McAllen, Rob; Culloty, Sarah C.

    2016-11-01

    The European sea squirt Ascidiella aspersa is a solitary tunicate native to the northeastern Atlantic, commonly found in shallow and sheltered marine ecosystems where it is capable of forming large clumps and outcompeting other invertebrate fauna at settlement. To date, there have been relatively few studies looking at the reproductive biology and health status of this invasive species. Between 2006 and 2010 sampling of a native population took place to investigate gametogenesis and reproductive cycle and to determine the impact of settlement depth on reproduction. In addition, parasite diversity and impact was assessed. A staging system to assess reproductive development was determined. The study highlighted that from year to year the tunicate could change its reproductive strategy from single sex to hermaphrodite, with spawning possible throughout the year. Depth did not impact on sex determination, however, gonad maturation and spawning occurred earlier in individuals in deeper waters compared to shallow depth and it also occurred later in A. aspersa at sites further away from the open sea. Four significant parasite groups including eugregarines, ciliates, trematodes and turbellarians were detected and prevalence of parasite infections increased in A. aspersa at sites with a reduced water flow rate. This study demonstrates the high biotic potential of this ascidian bioinvader to have a negative impact on native fauna in an introduced ecosystem, due to its highly efficient reproductive and resource allocation strategies. Artificial structures such as mooring lines can harbour large aggregations of A. aspersa, however, these manmade habitats may facilitate the colonisation and establishment of this invasive species in the benthos. Additionally, the parasite communities that A. aspersa harbour may also exacerbate its negative impact, both ecologically and economically, in an introduced area by possibly leading to the emergence of new disease in native species i

  15. A methodical microarray design enables surveying of expression of a broader range of genes in Ciona intestinalis.

    PubMed

    Matsumae, Hiromi; Hamada, Mayuko; Fujie, Manabu; Niimura, Yoshihito; Tanaka, Hiroshi; Kawashima, Takeshi

    2013-04-25

    We provide a new oligo-microarray for Ciona intestinalis, based on the NimbleGen 12-plex×135k format. The array represents 106,285 probes, which is more than double the probe number of the currently available 44k microarray. These probes cover 99.2% of the transcripts in the KyotoHoya (KH) models, published in 2008, and they contain 81.1% of the entries in the UniGene database that are not included in the KH models. In this paper, we show that gene expression levels measured by this new 135k microarray are highly correlated with those obtained by the existing 44k microarray for genes common to both arrays. We also investigated gene expression using samples obtained from the ovary and the neural complex of adult C. intestinalis, showing that the expression of tissue-specific genes is consistent with previous reports. Approximately half of the highly expressed genes identified in the 135k microarray are not included in the previous microarray. The high coverage of gene models by this microarray made it possible to identify splicing variants for a given transcript. The 135k microarray is useful in investigating the functions of genes that are not yet well characterized. Detailed information about this 135k microarray is accessible at no charge from supplemental materials, NCBI Gene Expression Omnibus (GEO), and http://marinegenomics.oist.jp.

  16. Transmission of cyanobacterial symbionts during embryogenesis in the coral reef ascidians Trididemnum nubilum and T. clinides (Didemnidae, Ascidiacea, Chordata).

    PubMed

    Kojima, Aoi; Hirose, Euichi

    2012-02-01

    Vertical transmission of cyanobacterial symbionts occurs in didemnid ascidians harboring Prochloron as an obligate symbiont; the photosymbionts are transferred from the parental ascidian colony to the offspring in various ways depending on host species. Although several didemnids harbor non-Prochloron cyanobacteria in their tunics, few studies have reported the processes of vertical transmission in these didemnids. Here we describe the histological processes of the transmission of cyanobacteria in two didemnids, Trididemnum nubilum harboring Synechocystis and T. clinides harboring three cyanobacterial species. In both species, the photosymbionts in the tunic of the parent colony were apparently captured by the tunic cells of the host and transferred to the embryos brooded in the tunic. The symbiont cells were then incorporated into the inner tunic of the embryo. This mode of transmission is essentially the same as that of T. miniatum harboring Prochloron in the tunic, although there are some differences among species in the timing of the release of the symbionts from the tunic cells. We suggest that the similar modes of vertical transmission are an example of convergent evolution caused by constraints in the distribution patterns of symbiont cells in the host colony.

  17. Deep sequencing of mixed total DNA without barcodes allows efficient assembly of highly plastic ascidian mitochondrial genomes.

    PubMed

    Rubinstein, Nimrod D; Feldstein, Tamar; Shenkar, Noa; Botero-Castro, Fidel; Griggio, Francesca; Mastrototaro, Francesco; Delsuc, Frédéric; Douzery, Emmanuel J P; Gissi, Carmela; Huchon, Dorothée

    2013-01-01

    Ascidians or sea squirts form a diverse group within chordates, which includes a few thousand members of marine sessile filter-feeding animals. Their mitochondrial genomes are characterized by particularly high evolutionary rates and rampant gene rearrangements. This extreme variability complicates standard polymerase chain reaction (PCR) based techniques for molecular characterization studies, and consequently only a few complete Ascidian mitochondrial genome sequences are available. Using the standard PCR and Sanger sequencing approach, we produced the mitochondrial genome of Ascidiella aspersa only after a great effort. In contrast, we produced five additional mitogenomes (Botrylloides aff. leachii, Halocynthia spinosa, Polycarpa mytiligera, Pyura gangelion, and Rhodosoma turcicum) with a novel strategy, consisting in sequencing the pooled total DNA samples of these five species using one Illumina HiSeq 2000 flow cell lane. Each mitogenome was efficiently assembled in a single contig using de novo transcriptome assembly, as de novo genome assembly generally performed poorly for this task. Each of the new six mitogenomes presents a different and novel gene order, showing that no syntenic block has been conserved at the ordinal level (in Stolidobranchia and in Phlebobranchia). Phylogenetic analyses support the paraphyly of both Ascidiacea and Phlebobranchia, with Thaliacea nested inside Phlebobranchia, although the deepest nodes of the Phlebobranchia-Thaliacea clade are not well resolved. The strategy described here thus provides a cost-effective approach to obtain complete mitogenomes characterized by a highly plastic gene order and a fast nucleotide/amino acid substitution rate.

  18. Mediterranean diet and longevity.

    PubMed

    Trichopoulou, A; Vasilopoulou, E

    2000-12-01

    Mortality statistics from the WHO database covering the period 1960 to 1990 have provided intriguing evidence that something unusual has been affecting in a beneficial way the health of the Mediterranean population. In recent papers, which evaluated the evidence accumulated over the last three decades, it was concluded that the traditional Mediterranean diet meets several important criteria for a healthy diet. Direct evidence in support of the beneficial properties of the Mediterranean diet has also become available. These data were derived from three studies, which have used a diet score, devised a priori on the basis of eight desirable key features of the traditional common diet in the Mediterranean region. The conclusion of these studies is that a diet that adheres to the principles of the traditional Mediterranean one is associated with longer survival. The Greek version of the Mediterranean diet is dominated by the consumption of olive oil and by high consumption of vegetables and fruits. Antioxidants represent a common element in these foods and an antioxidant action provides a plausible explanation for the apparent benefits. Wild edible greens frequently eaten in rural Greece in the form of salads and pies contain very high quantities of flavonoids-- considerably higher than those found in red wine or black tea. While there is no direct evidence that these antioxidants are central to the benefits of the Mediterranean Diet, indirect evidence from epidemiological data and the increasing understanding of their mechanisms of action suggest that antioxidants may play a major role.

  19. Fatty Acid and Lipid Profiles with Emphasis on n-3 Fatty Acids and Phospholipids from Ciona intestinalis.

    PubMed

    Zhao, Yadong; Wang, Miao; Lindström, Mikael E; Li, Jiebing

    2015-10-01

    In order to establish Ciona intestinalis as a new bioresource for n-3 fatty acids-rich marine lipids, the animal was fractionated into tunic and inner body tissues prior to lipid extraction. The lipids obtained were further classified into neutral lipids (NL), glycolipids (GL) and phospholipids (PL) followed by qualitative and quantitative analysis using GC-FID, GC-MS, (1)H NMR, 2D NMR, MALDI-TOF-MS and LC-ESI-MS methods. It was found that the tunic and inner body tissues contained 3.42-4.08% and 15.9-23.4% of lipids respectively. PL was the dominant lipid class (42-60%) irrespective of the anatomic fractions. From all lipid fractions and classes, the major fatty acids were 16:0, 18:1n-9, C20:1n-9, C20:5n-3 (EPA) and C22:6n-3 (DHA). The highest amounts of long chain n-3 fatty acids, mainly EPA and DHA, were located in PL from both body fractions. Cholestanol and cholesterol were the dominant sterols together with noticeable amounts of stellasterol, 22 (Z)-dehydrocholesterol and lathosterol. Several other identified and two yet unidentified sterols were observed for the first time from C. intestinalis. Different molecular species of phosphatidylcholine (34 species), sphingomyelin (2 species), phosphatidylethanolamine (2 species), phosphatidylserine (10 species), phosphatidylglycerol (9 species), ceramide (38 species) and lysophospholipid (5 species) were identified, representing the most systematic PL profiling knowledge so far for the animal. It could be concluded that C. intestinalis lipids should be a good alternative for fish oil with high contents of n-3 fatty acids. The lipids would be more bioavailable due to the presence of the fatty acids being mainly in the form of PL. PMID:26233815

  20. Toxic effects of two pesticides, Imazalil and Triadimefon, on the early development of the ascidian Phallusia mammillata (Chordata, Ascidiacea).

    PubMed

    Pennati, Roberta; Groppelli, Silvia; Zega, Giuliana; Biggiogero, Maira; De Bernardi, Fiorenza; Sotgia, Cristina

    2006-09-12

    Azole compounds are fungicides used in agriculture and in clinical area and are suspected to produce craniofacial malformations in vertebrates. Toxicity tests on sperm viability, fertilization and embryogenesis of the solitary ascidian Phallusia mammillata were performed to evaluate the effects of two azole derivatives, Imazalil and Triadimefon. Ascidian (Chordata, Ascidiacea) embryos and larvae could provide biological criteria for seawater quality standards because the larvae are lecitotrophic and have a short pelagic period, allowing to run the larval toxicity tests over a short period of time. Imazalil and Triadimefon proved to have strong consequences on P. mammillata. They could influence the reproductive rate of the animal exerting their effects at different levels: acting as spermiotoxic agents, inhibiting fertilization and impairing embryological development. Fertilization rate significantly decreased after 30min exposure of sperm to 25microM Imazalil (P<0.0001) and after exposure of both gametes to 50microM Imazalil (P<0.05) and 1mM Triadimefon (P<0.0001) as compared to controls. Malformations caused by exposure of embryos to both substances were dose dependent. Imazalil median teratogenic concentration (TC50 concentration, the concentration that resulted in 50% malformed larvae) value was 0.67microM and median lethal concentration (LC50, the concentration that resulted in 50% embryos dead before completing the development) value was 10.23microM while for Triadimefon TC50 value was 29.56 and LC50 value was 173.7microM. Larvae developed from embryos treated with Imazalil and Triadimefon showed alterations of the anterior structures of the trunk: papillary nerves and the anterior central nervous system failed to correctly differentiate, as showed by immunostaining with anti-beta-tubulin antibody. Comparing the anomalies caused by retinoic acid, reported in a previous study, it was possible to hypothesize that malformations induced by Imazalil and

  1. An exceptional salt-tolerant antimicrobial peptide derived from a novel gene family of haemocytes of the marine invertebrate Ciona intestinalis.

    PubMed

    Fedders, Henning; Michalek, Matthias; Grötzinger, Joachim; Leippe, Matthias

    2008-11-15

    A novel gene family coding for putative antimicrobial peptides was identified in the EST (expressed sequence tag) database of the sea squirt Ciona intestinalis, and one of these genes was molecularly cloned from the Northern European Ciona subspecies. In situ hybridization and immunocytochemical analysis revealed that the natural peptide is synthesized and stored in a distinct haemocyte type, the univacuolar non-refractile granulocytes. By semiquantitative RT-PCR (reverse transcription-PCR) analysis, it was shown that the expression of the gene is markedly up-regulated in haemocytes after immune challenge. To evaluate the antimicrobial potency of the putative defence protein, we synthesized a peptide corresponding to its cationic core region. The peptide was highly effective against Gram-negative and Gram-positive bacteria including several human and marine pathogens as well as the yeast Candida albicans. Notably, the antibacterial activity of the peptide was retained at salt concentrations of up to 450 mM NaCl. Using two different methods we demonstrated that the peptide kills Gram-negative and Gram-positive bacteria by permeabilizing their cytoplasmic membranes. CD spectroscopy revealed that, in the presence of liposomes composed of negatively charged phospholipids, the peptide undergoes a conformational change and adopts an alpha-helical structure. Moreover, the peptide was virtually non-cytolytic for mammalian erythrocytes. Hence, the designed salt-tolerant antimicrobial peptide may represent a valuable template for the development of novel antibiotics.

  2. Verruculides A and B, two new protein tyrosine phosphatase 1B inhibitors from an Indonesian ascidian-derived Penicillium verruculosum.

    PubMed

    Yamazaki, Hiroyuki; Nakayama, Wataru; Takahashi, Ohgi; Kirikoshi, Ryota; Izumikawa, Yuta; Iwasaki, Kohei; Toraiwa, Kengo; Ukai, Kazuyo; Rotinsulu, Henki; Wewengkang, Defny S; Sumilat, Deiske A; Mangindaan, Remy E P; Namikoshi, Michio

    2015-08-15

    Two new merosesquiterpenes, verruculides A (1) and B (2), were isolated from a culture broth of the Indonesian ascidian-derived Penicillium verruculosum TPU1311, together with three known congeners, chrodrimanins A (3), B (4), and H (5). The structures of 1 and 2 were assigned on the basis of their spectroscopic data (1D and 2D NMR, HRMS, UV, CD, and IR). Compound 2 had a linear sesquiterpene moiety and was considered to be the derivative of the biosynthetic precursor for 1 and 3-5. Compounds 1, 3, and 5 inhibited the activity of protein tyrosine phosphatase 1B (PTP1B) with IC50 values of 8.4, 8.5, and 14.9 μM, respectively. Compound 2 showed 40% inhibition at 23.1 μM, while 4 was not active at 20.7 μM. PMID:26115570

  3. Verruculides A and B, two new protein tyrosine phosphatase 1B inhibitors from an Indonesian ascidian-derived Penicillium verruculosum.

    PubMed

    Yamazaki, Hiroyuki; Nakayama, Wataru; Takahashi, Ohgi; Kirikoshi, Ryota; Izumikawa, Yuta; Iwasaki, Kohei; Toraiwa, Kengo; Ukai, Kazuyo; Rotinsulu, Henki; Wewengkang, Defny S; Sumilat, Deiske A; Mangindaan, Remy E P; Namikoshi, Michio

    2015-08-15

    Two new merosesquiterpenes, verruculides A (1) and B (2), were isolated from a culture broth of the Indonesian ascidian-derived Penicillium verruculosum TPU1311, together with three known congeners, chrodrimanins A (3), B (4), and H (5). The structures of 1 and 2 were assigned on the basis of their spectroscopic data (1D and 2D NMR, HRMS, UV, CD, and IR). Compound 2 had a linear sesquiterpene moiety and was considered to be the derivative of the biosynthetic precursor for 1 and 3-5. Compounds 1, 3, and 5 inhibited the activity of protein tyrosine phosphatase 1B (PTP1B) with IC50 values of 8.4, 8.5, and 14.9 μM, respectively. Compound 2 showed 40% inhibition at 23.1 μM, while 4 was not active at 20.7 μM.

  4. A new genus of Asterocheridae (Copepoda: Siphonostomatoida) ectoassociate of the ascidian Eudistoma vannamei Millar, 1977 (Polycitoridae) from Brazil.

    PubMed

    Johnsson, Rodrigo; Bahia, Cristiano; Neves, Elizabeth

    2016-01-01

    Asterocheres Boeck, 1860 is the largest genus of the siphonostomatoid copepod family Asterocheridae, containing 63 valid species. The genus is known for its symbiotic relationships with many marine invertebrate taxa, especially sponges, cnidarians, bryozoans, and echinoderms. Recent studies have restricted the diagnosis of this genus. Consequently, many species are now considered as species inquirendae. The present paper describes a new species living externally on the tunic of Eudistoma vannamei Millar, 1977, an endemic ascidian from Brazil. As the new species does not fit Asterocheres in the strict sense, a new genus is erected to accommodate it. Setacheres gen. nov. is characterized by its possession of two distal setae on the third endopodal segment of P3, thus differing from the distal seta and spine pattern that is deemed as diagnostic of Asterocheres. A revision and comparison of Asterocheres´ species inquirendae revealed eight species sharing the same generic characteristics and were thus reallocated as members of the new genus.

  5. [APPLICATION OF FLOW CYTOMETRY FOR THE ANALYSIS OF CIRCULATING HEMOCYTE POPULATIONS IN THE ASCIDIAN HALOCYNTHIA AURANTIUM (PALLAS, 1787)].

    PubMed

    Sukhachev, A N; Dyachkov, I S; Kudryavtsev, I V; Kumeiko, V V; Tsybulskiy, A V; Polevshchikov, A V

    2015-01-01

    This study addresses the potentialities of flow cytometry in analyzing the composition of circulating hemocyte populations in the ascidian Halocynthia aurantium (Pallas, 1787) both using monoclonal antibodies (mAbs) against some human leukocyte conservative adhesion molecules and without mAbs. Flow cytometry, based on the assessment of forward and side scattering revealed five hemocyte populations. From the wide panel of antibodies against human leukocyte adhesion molecules (CD15, CD29, CD34, CD54, CD62L, CD62P, CD90, CD94, CD117, CD 166), only two mAbs (against CD54, CD90) displayed cross-reactivity with the H. aurantium hemocyte surface antigens. Distribution patterns of these antigens across the hemocyte populations have been analyzed. PMID:26281224

  6. A new genus of Asterocheridae (Copepoda: Siphonostomatoida) ectoassociate of the ascidian Eudistoma vannamei Millar, 1977 (Polycitoridae) from Brazil.

    PubMed

    Johnsson, Rodrigo; Bahia, Cristiano; Neves, Elizabeth

    2016-01-01

    Asterocheres Boeck, 1860 is the largest genus of the siphonostomatoid copepod family Asterocheridae, containing 63 valid species. The genus is known for its symbiotic relationships with many marine invertebrate taxa, especially sponges, cnidarians, bryozoans, and echinoderms. Recent studies have restricted the diagnosis of this genus. Consequently, many species are now considered as species inquirendae. The present paper describes a new species living externally on the tunic of Eudistoma vannamei Millar, 1977, an endemic ascidian from Brazil. As the new species does not fit Asterocheres in the strict sense, a new genus is erected to accommodate it. Setacheres gen. nov. is characterized by its possession of two distal setae on the third endopodal segment of P3, thus differing from the distal seta and spine pattern that is deemed as diagnostic of Asterocheres. A revision and comparison of Asterocheres´ species inquirendae revealed eight species sharing the same generic characteristics and were thus reallocated as members of the new genus. PMID:27395122

  7. Anticancer effects of brominated indole alkaloid Eudistomin H from marine ascidian Eudistoma viride against cervical cancer cells (HeLa).

    PubMed

    Rajesh, Rajaian Pushpabai; Annappan, Murugan

    2015-01-01

    Marine invertebrates called ascidians are prolific producers of bioactive substances. The ascidian Eudistoma viride, distributed along the Southeast coast of India, was investigated for its in vitro cytotoxic activity against human cervical carcinoma (HeLa) cells by the MTT assay. The crude methanolic extract of E. viride, with an IC50 of 53 μg/ml, was dose-dependently cytotoxic. It was more potent at 100 μg/ml than cyclohexamide (1 μg/ml), reducing cell viability to 9.2%. Among nine fractions separated by chromatography, ECF-8 exhibited prominent cytoxic activity at 10 μg/ml. The HPLC fraction EHF-21 of ECF-8 was remarkably dose- and time-dependently cytotoxic, with 39.8% viable cells at 1 μg/ml compared to 51% in cyclohexamide-treated cells at the same concentration; the IC50 was 0.49 μg/ml. Hoechst staining of HeLa cells treated with EHF-21 at 0.5 μg/ml revealed apoptotic events such an cell shrinkage, membrane blebbing, chromatin condensation and formation of apoptotic bodies. Cell size and granularity study showed changes in light scatter, indicating the characteristic feature of cells dying by apoptosis. The cell-cycle analysis of HeLa cells treated with fraction EHF-21 at 1 μg/ml showed the marked arrest of cells in G0/G1, S and G2/M phases and an increase in the sub G0/G1 population indicated an increase in the apoptotic cell population. The statistical analysis of the sub-G1 region showed a dose-dependent induction of apoptosis. DNA fragmentation was also observed in HeLa cells treated with EHF-21. The active EHF-21 fraction, a brominated indole alkaloid Eudistomin H, led to apoptotic death of HeLa cells.

  8. Ascidian eggs block polyspermy by two independent mechanisms: one at the egg plasma membrane, the other involving the follicle cells.

    PubMed

    Lambert, C; Goudeau, H; Franchet, C; Lambert, G; Goudeau, M

    1997-09-01

    Many ascidians live in clumps and usually release sperm before the eggs. Consequently, eggs are often spawned into dense clouds of sperm. Because fertilization by more than a single sperm is lethal, ascidians have evolved at least two successive blocks to polyspermy: the rapid release of a glycosidase that inhibits sperm binding to the vitelline coat (VC) and a subsequent change in membrane potential that prevents supernumerary sperm-egg fusion. This paper shows that (1) these two blocks can be uncoupled by the use of suramin, and (2) most of the glycosidase appears to be from the follicle cells, which are accessory cells on the outside of the egg VC. Phallusia mammillata eggs initially bind numerous sperm but, after the glycosidase is released, only a few additional sperm bind. Intact eggs in 20 microM suramin release glycosidase, but the electrical response is inhibited; sperm swim actively and bind to the VC but fail to penetrate. Suramin treatment is completely reversible; intact eggs exhibit the electrical response an average of 11 minutes after the drug is washed out. Sperm must contact the follicle cells before passing through the VC; eggs with the VC removed and fertilized in the presence of 20 microM suramin show the electrical response 35% of the time, thus VC removal enhances sperm entry. Like the intact eggs, 100% of the naked eggs respond electrically to fertilization after the drug is washed out. Follicle cells that are isolated by calcium magnesium free seawater and then returned to complete seawater release N-acetylglucosaminidase activity in response to sperm. Thus, these eggs have two blocks to polyspermy that operate in sequence: an early first block resulting from enzymatic modification of the VC by N-acetylglucosaminidase released primarily from follicle cells and a second electrical block operating at the egg plasma membrane level and requiring sperm-egg fusion. PMID:9266770

  9. Ascidian eggs block polyspermy by two independent mechanisms: one at the egg plasma membrane, the other involving the follicle cells.

    PubMed

    Lambert, C; Goudeau, H; Franchet, C; Lambert, G; Goudeau, M

    1997-09-01

    Many ascidians live in clumps and usually release sperm before the eggs. Consequently, eggs are often spawned into dense clouds of sperm. Because fertilization by more than a single sperm is lethal, ascidians have evolved at least two successive blocks to polyspermy: the rapid release of a glycosidase that inhibits sperm binding to the vitelline coat (VC) and a subsequent change in membrane potential that prevents supernumerary sperm-egg fusion. This paper shows that (1) these two blocks can be uncoupled by the use of suramin, and (2) most of the glycosidase appears to be from the follicle cells, which are accessory cells on the outside of the egg VC. Phallusia mammillata eggs initially bind numerous sperm but, after the glycosidase is released, only a few additional sperm bind. Intact eggs in 20 microM suramin release glycosidase, but the electrical response is inhibited; sperm swim actively and bind to the VC but fail to penetrate. Suramin treatment is completely reversible; intact eggs exhibit the electrical response an average of 11 minutes after the drug is washed out. Sperm must contact the follicle cells before passing through the VC; eggs with the VC removed and fertilized in the presence of 20 microM suramin show the electrical response 35% of the time, thus VC removal enhances sperm entry. Like the intact eggs, 100% of the naked eggs respond electrically to fertilization after the drug is washed out. Follicle cells that are isolated by calcium magnesium free seawater and then returned to complete seawater release N-acetylglucosaminidase activity in response to sperm. Thus, these eggs have two blocks to polyspermy that operate in sequence: an early first block resulting from enzymatic modification of the VC by N-acetylglucosaminidase released primarily from follicle cells and a second electrical block operating at the egg plasma membrane level and requiring sperm-egg fusion.

  10. Anticancer effects of brominated indole alkaloid Eudistomin H from marine ascidian Eudistoma viride against cervical cancer cells (HeLa).

    PubMed

    Rajesh, Rajaian Pushpabai; Annappan, Murugan

    2015-01-01

    Marine invertebrates called ascidians are prolific producers of bioactive substances. The ascidian Eudistoma viride, distributed along the Southeast coast of India, was investigated for its in vitro cytotoxic activity against human cervical carcinoma (HeLa) cells by the MTT assay. The crude methanolic extract of E. viride, with an IC50 of 53 μg/ml, was dose-dependently cytotoxic. It was more potent at 100 μg/ml than cyclohexamide (1 μg/ml), reducing cell viability to 9.2%. Among nine fractions separated by chromatography, ECF-8 exhibited prominent cytoxic activity at 10 μg/ml. The HPLC fraction EHF-21 of ECF-8 was remarkably dose- and time-dependently cytotoxic, with 39.8% viable cells at 1 μg/ml compared to 51% in cyclohexamide-treated cells at the same concentration; the IC50 was 0.49 μg/ml. Hoechst staining of HeLa cells treated with EHF-21 at 0.5 μg/ml revealed apoptotic events such an cell shrinkage, membrane blebbing, chromatin condensation and formation of apoptotic bodies. Cell size and granularity study showed changes in light scatter, indicating the characteristic feature of cells dying by apoptosis. The cell-cycle analysis of HeLa cells treated with fraction EHF-21 at 1 μg/ml showed the marked arrest of cells in G0/G1, S and G2/M phases and an increase in the sub G0/G1 population indicated an increase in the apoptotic cell population. The statistical analysis of the sub-G1 region showed a dose-dependent induction of apoptosis. DNA fragmentation was also observed in HeLa cells treated with EHF-21. The active EHF-21 fraction, a brominated indole alkaloid Eudistomin H, led to apoptotic death of HeLa cells. PMID:25550562

  11. Neural induction suppresses early expression of the inward-rectifier K+ channel in the ascidian blastomere.

    PubMed Central

    Okamura, Y; Takahashi, K

    1993-01-01

    1. Early expression of ion channels following neural induction was examined in isolated, cleavage-arrested blastomeres from the ascidian embryo using a two-electrode voltage clamp. Currents were recorded from the isolated, cleavage-arrested blastomere, a4-2, after treatment with serine protease, subtilisin, which induces neural differentiation as consistently as cell contact. 2. The inward-rectifier K+ current increased at the late gastrula stage shortly after the sensitive period for neural induction both in the induced (protease-treated) and uninduced cells. Ca2+ channels, characteristic of epidermal-type differentiation, and delayed-rectifier K+ channels and differentiated-type Na+ channels, characteristic of neural-type differentiation appeared much later than the inward-rectifier K+ channels, at a time corresponding to the tail bud stage of the intact embryo. 3. When cells were treated with subtilisin during the critical period for neural induction, the increase in the inward-rectifier K+ current from the late gastrula stage to the neurula stage was about three times smaller (3.67 +/- 1.74 nA, mean +/- S.D., n = 14) than in untreated cells (11.25 +/- 3.10 nA, n = 26). The same changes in the inward-rectifier K+ channel were also observed in a4 2 blastomeres which were induced by cell contact with an A4-1 blastomere. However, when cells were treated with subtilisin after the critical period for neural induction, the amplitude of the inward-rectifier K+ current was the same as in untreated cells. Thus the expressed level of the inward-rectifier K+ channel was linked to the determination of neural or epidermal cell types. 4. There was no significant difference in the input capacitance of induced and uninduced cells, indicating that the difference in the amplitude of the inward-rectifier K+ currents derived from a difference in the channel density rather than a difference in cell surface area. 5. The expression of the inward-rectifier K+ channel at the late

  12. Ascidian and amphioxus Adh genes correlate functional and molecular features of the ADH family expansion during vertebrate evolution.

    PubMed

    Cañestro, Cristian; Albalat, Ricard; Hjelmqvist, Lars; Godoy, Laura; Jörnvall, Hans; Gonzàlez-Duarte, Roser

    2002-01-01

    The alcohol dehydrogenase (ADH) family has evolved into at least eight ADH classes during vertebrate evolution. We have characterized three prevertebrate forms of the parent enzyme of this family, including one from an urochordate (Ciona intestinalis) and two from cephalochordates (Branchiostoma floridae and Branchiostoma lanceolatum). An evolutionary analysis of the family was performed gathering data from protein and gene structures, exon-intron distribution, and functional features through chordate lines. Our data strongly support that the ADH family expansion occurred 500 million years ago, after the cephalochordate/vertebrate split, probably in the gnathostome subphylum line of the vertebrates. Evolutionary rates differ between the ancestral, ADH3 (glutathione-dependent formaldehyde dehydrogenase), and the emerging forms, including the classical alcohol dehydrogenase, ADH1, which has an evolutionary rate 3.6-fold that of the ADH3 form. Phylogenetic analysis and chromosomal mapping of the vertebrate Adh gene cluster suggest that family expansion took place by tandem duplications, probably concurrent with the extensive isoform burst observed before the fish/tetrapode split, rather than through the large-scale genome duplications also postulated in early vertebrate evolution. The absence of multifunctionality in lower chordate ADHs and the structures compared argue in favor of the acquisition of new functions in vertebrate ADH classes. Finally, comparison between B. floridae and B. lanceolatum Adhs provides the first estimate for a cephalochordate speciation, 190 million years ago, probably concomitant with the beginning of the drifting of major land masses from the Pangea.

  13. A forkhead gene related to HNF-3beta is required for gastrulation and axis formation in the ascidian embryo.

    PubMed

    Olsen, C L; Jeffery, W R

    1997-09-01

    We have isolated a member of the HNF-3/forkhead gene family in ascidians as a means to determine the role of winged-helix genes in chordate development. The MocuFH1 gene, isolated from a Molgula oculata cDNA library, exhibits a forkhead DNA-binding domain most similar to zebrafish axial and rodent HNF-3beta. MocuFH1 is a single copy gene but there is at least one other related forkhead gene in the M. oculata genome. The MocuFH1 gene is expressed in the presumptive endoderm, mesenchyme and notochord cells beginning during the late cleavage stages. During gastrulation, MocuFH1 expression occurs in the prospective endoderm cells, which invaginate at the vegetal pole, and in the presumptive notochord and mesenchyme cells, which involute over the anterior and lateral lips of the blastopore, respectively. However, this gene is not expressed in the presumptive muscle cells, which involute over the posterior lip of the blastopore. MocuFH1 expression continues in the same cell lineages during neurulation and axis formation, however, during the tailbud stage, MocuFH1 is also expressed in ventral cells of the brain and spinal cord. The functional role of the MocuFH1 gene was studied using antisense oligodeoxynucleotides (ODNs), which transiently reduce MocuFH1 transcript levels during gastrulation. Embryos treated with antisense ODNs cleave normally and initiate gastrulation. However, gastrulation is incomplete, some of the endoderm and notochord cells do not enter the embryo and undergo subsequent movements, and axis formation is abnormal. In contrast, the prospective muscle cells, which do not express MocuFH1, undergo involution and later express muscle actin and acetylcholinesterase, markers of muscle cell differentiation. The results suggest that MocuFH1 is required for morphogenetic movements of the endoderm and notochord precursor cells during gastrulation and axis formation. The effects of inhibiting MocuFH1 expression on embryonic axis formation in ascidians are

  14. There are many Mediterranean diets.

    PubMed

    Noah, A; Truswell, A S

    2001-01-01

    Interest in Mediterranean diet began 30 years ago, when Ancel Keys published the results of the famous Seven Countries Study, Since 1945, almost 1.3 million people have come to Australia from Mediterranean countries as new settlers. There are 18 countries with coasts on the Mediterranean sea: Spain, southern France, Italy, Malta, Croatia, Bosnia, Albania, Greece, Cyprus, Turkey, Syria, Lebanon, Egypt, Libya, Malta, Tunisia, Algeria and Morocco. This study from which this report derives aims to investigate the influence of the food habits of immigrants from Mediterranean countries on Australian food intake. Here we look at the 'traditional' food habits of the above Mediterranean countries as told by 102 people we interviewed in Sydney, who came from 18 Mediterranean countries to Sydney. Most of the informants were women, their age ranged from 35 to 55 years. The interview was open-ended and held in the informant's home. It usually lasted around 1 1/2 hours. The interview had three parts. Personal information was obtained, questions relating to the food habits of these people back in their original Mediterranean countries and how their food intake and habits have changed in Australia were also asked. From the interviews, we have obtained a broad picture of 'traditional' food habits in different Mediterranean countries. The interview data was checked with books of recipes for the different countries. While there were similarities between the countries, there are also important differences in the food habits of the Mediterranean countries. Neighbouring countries' food habits are closer than those on opposite sides of the Mediterranean Sea. We suggest that these food habits can be put into four groups. The data here refer to food habits in Mediterranean countries 20 or 30 years ago, as they were recovering from the Second World War. There is no single ideal Mediterranean diet. Nutritionists who use the concept should qualify the individual country and the time in

  15. A voltage-gated chloride channel in ascidian embryos modulated by both the cell cycle clock and cell volume.

    PubMed Central

    Villaz, M; Cinniger, J C; Moody, W J

    1995-01-01

    1. Eggs of the ascidian Boltenia villosa have an inwardly rectifying Cl- current whose amplitude varies by more than 10-fold during each cell cycle, the largest amplitude being at exit from M-phase. We examined whether this current was also sensitive to changes in cell volume. 2. Cell swelling, produced by direct inflation through a whole-cell recording pipette, greatly increased the amplitude of the Cl- current at all stages of the cell cycle in activated eggs. Swelling was much less effective in unfertilized eggs. 3. The increase in Cl- current amplitude continued for 10-20 min after an increase in diameter that was complete in 10 s, suggesting the involvement of a second messenger system in the response. 4. Treatment of unfertilized eggs with 6-dimethylaminopurine (DMAP), an inhibitor of cell cycle-dependent protein kinases, increased the amplitude of the Cl- current and its sensitivity to swelling to levels characteristic of fertilized eggs. 5. Osmotically produced swelling also increased Cl- current amplitude in unfertilized eggs. 6. We propose that dephosphorylation renders the Cl- channel functional, and that swelling or activation of the egg increases the sensitivity of the channel to dephosphorylation, perhaps by disrupting its links to the cytoskeleton. PMID:8576858

  16. Photoadaptation and protection against active forms of oxygen in the symbiotic procaryote Prochloron sp. and its ascidian host

    SciTech Connect

    Lesser, M.P.; Stochaj, W.R. )

    1990-06-01

    Superoxide dismutase, ascorbate, peroxidase, and catalase activities were studied in the symbiotic photosynthetic procaryote Prochloron sp. and its ascidian host Lissoclinum patella. The protein-specific activities of these antioxidant enzymes in the Prochloron sp. and L. patella collected at different depths from the Great Barrier Reef, Australia, were directly proportional to irradiance, whereas the pigment concentrations in the Prochloron sp. were inversely proportional to irradiance. The presence of a cyanide-sensitive superoxide dismutase, presumably a Cu-An metalloprotein, in the Prochloron sp. extends the possible phylogenetic distribution of this protein. The concentration of UV-absorbing mycosporine-like amino acids in inversely proportional to irradiance in both the host and symbiont, suggesting that these compounds may not provide sufficient protection against UV radiation in high-irradiance environments. The significant differences in the specific activities of these antioxidant enzymes, cellular photosynthetic pigment concentrations, and UV-absorbing compounds from high- and low-irradiance habitats constitute an adaptive response to different photic environments. These photoadaptive responses are essential to prevent inhibition of photosynthesis by high fluxes of visible and UV radiation.

  17. Msxb is a core component of the genetic circuitry specifying the dorsal and ventral neurogenic midlines in the ascidian embryo.

    PubMed

    Roure, Agnès; Darras, Sébastien

    2016-01-01

    The tail ascidian larval peripheral nervous system is made up of epidermal sensory neurons distributed more or less regularly in ventral and dorsal midlines. Their formation occurs in two-steps: the ventral and dorsal midlines are induced as neurogenic territories by Fgf9/16/20 and Admp respectively. The Delta2/Notch interaction then controls the number of neurons that form. The genetic machinery acting between the inductive processes taking place before gastrulation and neuron specification at tailbud stages are largely unknown. The analysis of seven transcription factors expressed in the forming midlines revealed an unexpected complexity and dynamic of gene expression. Their systematic overexpression confirmed that these genes do not interact following a linear cascade of activation. However, the integration of our data revealed the distinct key roles of the two upstream factors Msxb and Nkx-C that are the earliest expressed genes and the only ones able to induce neurogenic midline and ESN formation. Our data suggest that Msxb would be the primary midline gene integrating inputs from the ventral and dorsal inducers and launching a pan-midline transcriptional program. Nkx-C would be involved in tail tip specification, in maintenance of the pan-midline network and in a posterior to anterior wave controlling differentiation. PMID:26592100

  18. Southeastern Mediterranean Panorama

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This oblique northwestward looking panorama view shows the southeastern Mediterranean (29.0N, 33.0E) in great detail. The Sinai Peninsula, the eastern Arabian Desert, the Nile River Valley and Delta as well as the Qatara Depression in Egypt are all prominently portrayed. Even Mt. Sinai is visible in the lower left center of the view. The dusty atmosphere of the region can be seen as a general haziness in the atmosphere.

  19. SMED - Sulphur MEditerranean Dispersion

    NASA Astrophysics Data System (ADS)

    Salerno, Giuseppe G.; Sellitto, Pasquale; Corradini, Stefano; Di Sarra, Alcide Giorgio; Merucci, Luca; Caltabiano, Tommaso; La Spina, Alessandro

    2016-04-01

    Emissions of volcanic gases and particles can have profound impacts on terrestrial environment, atmospheric composition, climate forcing, and then on human health at various temporal and spatial scales. Volcanic emissions have been identified as one of the largest sources of uncertainty in our understanding of recent climate change trends. In particular, a primary role is acted by sulphur dioxide emission due to its conversion to volcanic sulphate aerosol via atmospheric oxidation. Aerosols may play a key role in the radiative budget and then in photochemistry and tropospheric composition. Mt. Etna is one of the most prodigious and persistent emitters of gasses and particles on Earth, accounting for about 10% of global average volcanic emission of CO2 and SO2. Its sulphur emissions stand for 0.7 × 106 t S/yr9 and then about 10 times bigger than anthropogenic sulphur emissions in the Mediterranean area. Centrepiece of the SMED project is to advance the understanding of volcanogenic sulphur dioxide and sulphate aerosol particles dispersion and radiative impact on the downwind Mediterranean region by an integrated approach between ground- and space-based observations and modelling. Research is addressed by exploring the potential relationship between proximal SO2 flux and aerosol measured remotely in the volcanic plume of Mt. Etna between 2000 and 2014 and distal aerosol ground-based measurements in Lampedusa, Greece, and Malta from AERONET network. Ground data are combined with satellite multispectral polar and geostationary imagers able to detect and retrieve volcanic ash and SO2. The high repetition time of SEVIRI (15 minutes) will ensure the potential opportunity to follow the entire evolution of the volcanic cloud, while, the higher spatial resolution of MODIS (1x1 km2), are exploited for investigating the probability to retrieve volcanic SO2 abundances from passive degassing. Ground and space observations are complemented with atmospheric Lagrangian model

  20. The Hemolymph of the ascidian Styela plicata (Chordata-Tunicata) contains heparin inside basophil-like cells and a unique sulfated galactoglucan in the plasma.

    PubMed

    de Barros, Cintia M; Andrade, Leonardo R; Allodi, Silvana; Viskov, Christian; Mourier, Pierre A; Cavalcante, Moisés C M; Straus, Anita H; Takahashi, Helio K; Pomin, Vitor H; Carvalho, Vinicius F; Martins, Marco A; Pavão, Mauro S G

    2007-01-19

    The hemolymph of ascidians (Chordata-Tunicata) contains different types of hemocytes embedded in a liquid plasma. In the present study, heparin and a sulfated heteropolysaccharide were purified from the hemolymph of the ascidian Styela plicata. The heteropolysaccharide occurs free in the plasma, is composed of glucose ( approximately 60%) and galactose ( approximately 40%), and is highly sulfated. Heparin, on the other hand, occurs in the hemocytes, and high performance liquid chromatography of the products formed by degradation with specific lyases revealed that it is composed mainly by the disaccharides DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4)) (39.7%) and DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4))(6SO(4)) (38.2%). Small amounts of the 3-O-sulfated disaccharides DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4))(3SO(4)) (9.8%) and DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4))(3SO(4))(6SO(4)) (3.8%) were also detected. These 3-O-sulfated disaccharides were demonstrated to be essential for the binding of the hemocyte heparin to antithrombin III. Electron microscopy techniques were used to characterize the ultrastructure of the hemocytes and to localize heparin and histamine in these cells. At least five cell types were recognized and classified as univacuolated and multivacuolated cells, amebocytes, hemoblasts, and granulocytes. Immunocytochemistry showed that heparin and histamine co-localize in intracellular granules of only one type of hemocyte, the granulocyte. These results show for the first time that in ascidians, a sulfated galactoglucan circulates free in the plasma, and heparin occurs as an intracellular product of a circulating basophil-like cell.

  1. In vitro and in vivo efficacy of drugs against the protozoan parasite Azumiobodo hoyamushi that causes soft tunic syndrome in the edible ascidian Halocynthia roretzi (Drasche).

    PubMed

    Park, K H; Zeon, S-R; Lee, J-G; Choi, S-H; Shin, Y K; Park, K-I

    2014-04-01

    It was discovered recently that infection by a protozoan parasite, Azumiobodo hoyamushi, is the most probable cause for soft tunic syndrome in an edible ascidian, Halocynthia roretzi (Drasche). In an attempt to develop measures to eradicate the causative parasite, various drugs were tested for efficacy in vitro and in vivo. Of the 20 antiprotozoal drugs having different action mechanisms, five were found potent (24-h EC50  < 10 mg L(-1) ) in their parasite-killing effects: formalin, H2 O2 , bithionol, ClO2 and bronopol. Moderately potent drugs (10 < 24-h EC50  < 100 mg L(-1) ) were quinine, fumagillin, amphotericin B, ketoconazole, povidone-iodine, chloramine-T and benzalkonium chloride. Seven compounds, metronidazole, albendazole, paromomycin, nalidixic acid, sulfamonomethoxine, KMnO4 , potassium monopersulphate and citric acid, exhibited EC50  > 100 mg L(-1) . When ascidians were artificially infected with A. hoyamushi, treated using 40 mg L(-1) formalin, bronopol, ClO2 , or H2 O2 for 1 h and then monitored for 24 h, very low mortality was observed. However, the number of surviving parasite cells in the ascidian tunic tissues was significantly reduced by treating with 40 mg L(-1) formalin or ClO2 for 1 h. The data suggest that we might be able to develop a disinfection measure using a treatment regimen involving commonly available drugs.

  2. Biologically Active Acetylenic Amino Alcohol and N-Hydroxylated 1,2,3,4-Tetrahydro-β-carboline Constituents of the New Zealand Ascidian Pseudodistoma opacum.

    PubMed

    Wang, Jiayi; Pearce, A Norrie; Chan, Susanna T S; Taylor, Richard B; Page, Michael J; Valentin, Alexis; Bourguet-Kondracki, Marie-Lise; Dalton, James P; Wiles, Siouxsie; Copp, Brent R

    2016-03-25

    The first occurrence of an acetylenic 1-amino-2-alcohol, distaminolyne A (1), isolated from the New Zealand ascidian Pseudodistoma opacum, is reported. The isolation and structure elucidation of 1 and assignment of absolute configuration using the exciton coupled circular dichroism technique are described. In addition, a new N-9 hydroxy analogue (2) of the known P. opacum metabolite 7-bromohomotrypargine is also reported. Antimicrobial screening identified modest activity of 1 toward Escherichia coli, Staphylococcus aureus, and Mycobacterim tuberculosis, while 2 exhibited a moderate antimalarial activity (IC50 3.82 μM) toward a chloroquine-resistant strain (FcB1) of Plasmodium falciparum. PMID:26670413

  3. Reviving the Mediterranean Olive Community

    ERIC Educational Resources Information Center

    Zaferatos, Nicholas C.

    2011-01-01

    This article presents the findings of a collaborative investigation by six nongovernment organisations (NGOs) from five European-Mediterranean countries to identify a framework for reversing rural marginalisation in Mediterranean communities through sustainable forms of community-based agricultural development. The project brought together…

  4. Increased Inter-Colony Fusion Rates Are Associated with Reduced COI Haplotype Diversity in an Invasive Colonial Ascidian Didemnum vexillum

    PubMed Central

    Smith, Kirsty F.; Stefaniak, Lauren; Saito, Yasunori; Gemmill, Chrissen E. C.; Cary, S. Craig; Fidler, Andrew E.

    2012-01-01

    Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species. PMID:22303442

  5. Cardiovascular effects of lepadiformine, an alkaloid isolated from the ascidians Clavelina lepadiformis (Müller) and C. moluccensis (Sluiter).

    PubMed

    Jugé, M; Grimaud, N; Biard, J F; Sauviat, M P; Nabil, M; Verbist, J F; Petit, J Y

    2001-08-01

    The effects of lepadiformine, a natural marine alkaloid isolated from the ascidians Clavelina lepadiformis (Müller) and C. moluccensis (Sluiter), were studied in vivo by arterial blood pressure (aBP) recordings and electrocardiograms (ECG) in anaesthetised rats and in situ by peripheral vascular pressure recordings on perfused rabbit ear. Transmembrane resting (RP) and action (AP) potentials were also recorded by intracellular microelectrodes on electrically stimulated left ventricular papillary muscle and spontaneously beating atrium isolated from rat and frog hearts, respectively. Intravenous injection of lepadiformine (6mg/kg) produced marked bradycardia and a lengthening of ECG intervals as well as a transient decrease of aBP, which rapidly returned to normal. The decrease of aBP may have been related to a vasoconstrictor effect observed in the perfused ear experiment. Lepadiformine did not alter RP, but significantly lengthened the repolarising phase of AP in rat papillary muscle and frog atrium. Lepadiformine also mimicked the effect of Ba(2+) (0.2mM) on the rat AP repolarising phase. Moreover, the lengthening of the AP in frog atrium induced by lepadiformine still developed after the delayed outward K(+) current (I(K)) was blocked by tetraethylammonium (10mM). These observations suggest that lepadiformine-induced lengthening of AP duration was not due to a decrease of I(K), but may reasonably be attributed to a reduction of the inward rectifying K(+) current (I(K1)). This blockade of I(K1) could account for the cardiovascular effects of lepadiformine in vivo and in vitro and suggests that lepadiformine has antiarrhythmic properties.

  6. Action potential waveform voltage clamp shows significance of different Ca2+ channel types in developing ascidian muscle

    PubMed Central

    Dallman, Julia E; Dorman, Jennie B; Moody, William J

    2000-01-01

    Early in development, ascidian muscle cells generate spontaneous, long-duration action potentials that are mediated by a high-threshold, inactivating Ca2+ current. This spontaneous activity is required for appropriate physiological development.Mature muscle cells generate brief action potentials only in response to motor neuron input. The mature action potential is mediated by a high-threshold sustained Ca2+ current.Action potentials recorded from these two stages were imposed as voltage-clamp commands on cells of the same and different stages from which they were recorded. This strategy allowed us to study how immature and mature Ca2+ currents are optimized to their particular functions.Total Ca2+ entry during an action potential did not change during development. The developmental increase in Ca2+ current density exactly compensated for decreased spike duration. This compensation was a function purely of Ca2+ current density, not of the transition from immature to mature Ca2+ current types.In immature cells, Ca2+ entry was spread out over the entire waveform of spontaneous activity, including the interspike voltage trajectory. This almost continuous Ca2+ entry may be important in triggering Ca2+-dependent developmental programmes, and is a function of the slightly more negative voltage dependence of the immature Ca2+ current.In contrast, Ca2+ entry in mature cells was confined to the action potential itself, because of the slightly more positive voltage dependence of the mature Ca2+ current. This may be important in permitting rapid contraction-relaxation cycles during larval swimming.The inactivation of the immature Ca2+ current serves to limit the frequency and burst duration of spontaneous activity. The sustained kinetics of the mature Ca2+ current permit high-frequency firing during larval swimming. PMID:10766919

  7. Dust in the Mediterranean

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On July 24, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), acquired this true-color image of a large cloud of dust blowing from northern Africa across the Mediterranean Sea. The dust storm has persisted in the region for at least a week. In this image, the brownish dust plume appears to originate about 260 miles (400 km) east of Algiers, Algeria, and is blowing toward the northwest coast of Sardinia, Italy. SeaWiFS flies aboard the OrbView-2 Satellite. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE

  8. Co-expression of Foxa.a, Foxd and Fgf9/16/20 defines a transient mesendoderm regulatory state in ascidian embryos

    PubMed Central

    Hudson, Clare; Sirour, Cathy; Yasuo, Hitoyoshi

    2016-01-01

    In many bilaterian embryos, nuclear β-catenin (nβ-catenin) promotes mesendoderm over ectoderm lineages. Although this is likely to represent an evolutionary ancient developmental process, the regulatory architecture of nβ-catenin-induced mesendoderm remains elusive in the majority of animals. Here, we show that, in ascidian embryos, three nβ-catenin transcriptional targets, Foxa.a, Foxd and Fgf9/16/20, are each required for the correct initiation of both the mesoderm and endoderm gene regulatory networks. Conversely, these three factors are sufficient, in combination, to produce a mesendoderm ground state that can be further programmed into mesoderm or endoderm lineages. Importantly, we show that the combinatorial activity of these three factors is sufficient to reprogramme developing ectoderm cells to mesendoderm. We conclude that in ascidian embryos, the transient mesendoderm regulatory state is defined by co-expression of Foxa.a, Foxd and Fgf9/16/20. DOI: http://dx.doi.org/10.7554/eLife.14692.001 PMID:27351101

  9. Characterization of the teneurin C-terminal associated peptide (TCAP) in the vase tunicate, Ciona intestinalis: A novel peptide system associated with energy metabolism and reproduction.

    PubMed

    Colacci, Michael; De Almeida, Reuben; Chand, Dhan; Lovejoy, Sabine R; Sephton, Dawn; Vercaemer, Benedikte; Lovejoy, David A

    2015-05-15

    The vase tunicate, Ciona intestinalis, is a protochordate and is considered a sister lineage to the chordates. The recent sequencing of its genome has made this species a particularly important model to understand the genetic basis of vertebrate evolution. However, C. intestinalis is also a highly invasive species along the Atlantic coast of North America and other regions of the world which have caused considerable economic stress due to its biofouling actions and, in particular, negative impacts on the mussel- and oyster-based aquaculture industry. Despite this background, little is known about C. intestinalis physiology. The teneurin C-terminal associated peptides (TCAP) are a family of highly conserved peptide hormones found in most metazoans. Moreover, these peptides have been implicated in the inhibition of stress and stimulation of feeding-based metabolism. We have, therefore, identified this peptide using an in silico approach and characterized its immunological expression in tissues using a mouse polyclonal antiserum. These data indicate that its primary structure is more similar to invertebrate TCAPs relative to vertebrate TCAPs. Immunological expression indicates that it is highly expressed in the digestive tract and gonads consistent with findings in vertebrates. Synthetic mouse TCAP-1 administered into the brachial basket significantly increases the incidence of non-stress contractile behaviors. These findings support the hypothesis that TCAP is a bioactive peptide in C. intestinalis. Thus, C. intestinalis and tunicates in general may offer a simple model to investigate peptide interaction while providing information on how to control this invasive species.

  10. Structural investigations of the p53/p73 homologs from the tunicate species Ciona intestinalis reveal the sequence requirements for the formation of a tetramerization domain.

    PubMed

    Heering, Jan; Jonker, Hendrik R A; Löhr, Frank; Schwalbe, Harald; Dötsch, Volker

    2016-02-01

    Most members of the p53 family of transcription factors form tetramers. Responsible for determining the oligomeric state is a short oligomerization domain consisting of one β-strand and one α-helix. With the exception of human p53 all other family members investigated so far contain a second α-helix as part of their tetramerization domain. Here we have used nuclear magnetic resonance spectroscopy to characterize the oligomerization domains of the two p53-like proteins from the tunicate Ciona intestinalis, representing the closest living relative of vertebrates. Structure determination reveals for one of the two proteins a new type of packing of this second α-helix on the core domain that was not predicted based on the sequence, while the other protein does not form a second helix despite the presence of crucial residues that are conserved in all other family members that form a second helix. By mutational analysis, we identify a proline as well as large hydrophobic residues in the hinge region between both helices as the crucial determinant for the formation of a second helix. PMID:26473758

  11. Characterization of the teneurin C-terminal associated peptide (TCAP) in the vase tunicate, Ciona intestinalis: A novel peptide system associated with energy metabolism and reproduction.

    PubMed

    Colacci, Michael; De Almeida, Reuben; Chand, Dhan; Lovejoy, Sabine R; Sephton, Dawn; Vercaemer, Benedikte; Lovejoy, David A

    2015-05-15

    The vase tunicate, Ciona intestinalis, is a protochordate and is considered a sister lineage to the chordates. The recent sequencing of its genome has made this species a particularly important model to understand the genetic basis of vertebrate evolution. However, C. intestinalis is also a highly invasive species along the Atlantic coast of North America and other regions of the world which have caused considerable economic stress due to its biofouling actions and, in particular, negative impacts on the mussel- and oyster-based aquaculture industry. Despite this background, little is known about C. intestinalis physiology. The teneurin C-terminal associated peptides (TCAP) are a family of highly conserved peptide hormones found in most metazoans. Moreover, these peptides have been implicated in the inhibition of stress and stimulation of feeding-based metabolism. We have, therefore, identified this peptide using an in silico approach and characterized its immunological expression in tissues using a mouse polyclonal antiserum. These data indicate that its primary structure is more similar to invertebrate TCAPs relative to vertebrate TCAPs. Immunological expression indicates that it is highly expressed in the digestive tract and gonads consistent with findings in vertebrates. Synthetic mouse TCAP-1 administered into the brachial basket significantly increases the incidence of non-stress contractile behaviors. These findings support the hypothesis that TCAP is a bioactive peptide in C. intestinalis. Thus, C. intestinalis and tunicates in general may offer a simple model to investigate peptide interaction while providing information on how to control this invasive species. PMID:25687741

  12. Qibla in the Mediterranean

    NASA Astrophysics Data System (ADS)

    Rius-Piniés, Mònica

    Orientation toward Mecca has been compulsory for Muslims in all time periods and in all places. In fact, mosques were built in such a way as to help believers to pray toward the right direction. Nevertheless, the alignment of the sacred buildings was not always exact, and many did not actually face the Kaaba. There are many reasons for this "mistake", the main one being that at the time of the construction of the most important mosques, the astronomical and geographical knowledge needed to make accurate calculations was lacking. In the Mediterranean area, the scholars who were most involved in this task were the fuqahā' (experts in Islamic jurisprudence) who were sometimes well versed in astronomical knowledge or, at least, were skilled in the practice of popular astronomy. The combination of astronomy and religion, mixed with the political and topographical conditions, produces a unique area of study which remains controversial today.

  13. Familial Mediterranean Fever

    PubMed Central

    Migita, Kiyoshi; Agematsu, Kazunaga; Yazaki, Masahide; Nonaka, Fumiaki; Nakamura, Akinori; Toma, Tomoko; Kishida, Dai; Uehara, Ritei; Nakamura, Yoshikazu; Jiuchi, Yuka; Masumoto, Junya; Furukawa, Hiroshi; Ida, Hiroaki; Terai, Chihiro; Nakashima, Yoshikazu; Kawakami, Atsushi; Nakamura, Tadashi; Eguchi, Katsumi; Yasunami, Michio; Yachie, Akihiro

    2014-01-01

    Abstract Familial Mediterranean fever (FMF) is an autoinflammatory disease caused by MEditerranean FeVer gene (MEFV) mutations. In Japan, patients with FMF have been previously reported, including a mild or incomplete form. Several factors are presumed to contribute to the variable penetrance and to the phenotypic variability of FMF. We conducted the current study to investigate the correlation of variable clinical presentations and MEFV genotypic distributions in Japanese FMF patients. We analyzed demographic, clinical, and genetic data for 311 FMF patients enrolled in the study. Clinically, we classified FMF into 2 phenotypes: 1) the “typical” form of FMF, and 2) the “atypical” form of FMF according to the Tel Hashomer criteria. Patients with the typical FMF phenotype had a higher frequency of febrile episodes, a shorter duration of febrile attacks, more frequent thoracic pain, abdominal pain, a family history of FMF, and MEFV exon 10 mutations. Conversely, patients with the atypical FMF phenotype had a lower frequency of fever episodes and more frequent arthritis in atypical distribution, myalgia, and MEFV exon 3 mutations. Multivariate analysis showed that the variable associated with typical FMF presentation was the presence of MEFV exon 10 mutations. Typical FMF phenotype frequencies were decreased in patients carrying 2 or a single low-penetrance mutations compared with those carrying 2 or a single high-penetrance mutations (M694I), with an opposite trend for the atypical FMF phenotype. In addition, patients having more than 2 MEFV mutations had a younger disease onset and a higher prevalence of thoracic pain than those carrying a single or no mutations. Thus, MEFV exon 10 mutations are associated with the more typical FMF phenotype. In contrast, more than half of the Japanese FMF patients without MEFV exon 10 mutations presented with an atypical FMF phenotype, indicating that Japanese FMF patients tend to be divided into 2 phenotypes by a variation

  14. The Sexual and Mating System of the Shrimp Odontonia katoi (Palaemonidae, Pontoniinae), a Symbiotic Guest of the Ascidian Polycarpa aurata in the Coral Triangle

    PubMed Central

    Baeza, J. Antonio; Hemphill, Carrie A.; Ritson-Williams, Raphael

    2015-01-01

    Theory predicts that monogamy is adaptive in symbiotic crustaceans inhabiting relatively small and morphologically simple hosts in tropical environments where predation risk away from hosts is high. We tested this prediction in the shrimp Odontonia katoi, which inhabits the atrial chamber of the ascidian Polycarpa aurata in the Coral Triangle. Preliminary observations in O. katoi indicated that males were smaller than females, which is suggestive of sex change (protandry) in some symbiotic organisms. Thus, we first investigated the sexual system of O. katoi to determine if this shrimp was sequentially hermaphroditic. Morphological identification and size frequency distributions indicated that the population comprised males that, on average, were smaller than females. Gonad dissections demonstrated the absence of transitional individuals. Thus, O. katoi is a gonochoric species with reverse sexual dimorphism. The population distribution of O. katoi in its ascidian host did not differ significantly from a random distribution and shrimps inhabiting the same host individual as pairs were found with a frequency similar to that expected by chance alone. This is in contrast to that reported for other socially monogamous crustaceans in which pairs of heterosexual conspecifics are found in host individuals more frequently than expected by chance alone. Thus, the available information argues against monogamy in O. katoi. Furthermore, that a high frequency of solitary females were found brooding embryos and that the sex ratio was skewed toward females suggests that males might be roaming among hosts in search of receptive females in O. katoi. Symbiotic crustaceans can be used as a model system to understand the adaptive value of sexual and mating systems in marine invertebrates. PMID:25799577

  15. An ultraviolet-sensitive maternal mRNA encoding a cytoskeletal protein may be involved in axis formation in the ascidian embryo

    SciTech Connect

    Jeffery, W.R. )

    1990-09-01

    Ultraviolet (uv) irradiation of the vegetal hemisphere of fertilized eggs during ooplasmic segregation inhibits subsequent gastrulation and axis formation in ascidian embryos. The molecular basis of this phenomenon was investigated in by comparing in vivo protein synthesis and in vitro mRNA translation in normal and uv-irradiated embryos of the ascidian Styela clava. Analysis of protein synthesis by (35S)methionine incorporation, two-dimensional (2D) gel electrophoresis, and autoradiography showed that only 21 of 433 labeled polypeptides were missing or decreased in labeling intensity in uv-irradiated embryos. The most prominent of these was a 30,000 molecular weight (pI 6.0) polypeptide (p30). Extraction of gastrulae with the nonionic detergent Triton X-100 showed that p30 is retained in the detergent insoluble residue, suggesting that it is associated with the cytoskeleton. Several lines of evidence suggest that p30 may be involved in axis formation. First, p30 labeling peaks during gastrulation, when the embryonic axis is being established. Second, axis formation and p30 labeling are abolished by the same threshold uv dose, which is distinct from that required to inactivate muscle cell development. Third, the uv sensitivity period for abolishing p30 labeling and axis formation are both restricted to ooplasmic segregation. In vitro translation of egg RNA followed by 2D gel electrophoresis and autoradiography of the protein products showed that p30 is encoded by a maternal mRNA. The translation of p30 mRNA was abolished by uv irradiation of fertilized eggs during ooplasmic segregation suggesting that this message is a uv-sensitive target. The results are consistent with the hypothesis that uv irradiation blocks gastrulation and axis formation by inhibiting the translation of maternal mRNA localized in the vegetal hemisphere of the fertilized egg.

  16. The sexual and mating system of the shrimp Odontonia katoi (Palaemonidae, Pontoniinae), a symbiotic guest of the ascidian Polycarpa aurata in the Coral Triangle.

    PubMed

    Baeza, J Antonio; Hemphill, Carrie A; Ritson-Williams, Raphael

    2015-01-01

    Theory predicts that monogamy is adaptive in symbiotic crustaceans inhabiting relatively small and morphologically simple hosts in tropical environments where predation risk away from hosts is high. We tested this prediction in the shrimp Odontonia katoi, which inhabits the atrial chamber of the ascidian Polycarpa aurata in the Coral Triangle. Preliminary observations in O. katoi indicated that males were smaller than females, which is suggestive of sex change (protandry) in some symbiotic organisms. Thus, we first investigated the sexual system of O. katoi to determine if this shrimp was sequentially hermaphroditic. Morphological identification and size frequency distributions indicated that the population comprised males that, on average, were smaller than females. Gonad dissections demonstrated the absence of transitional individuals. Thus, O. katoi is a gonochoric species with reverse sexual dimorphism. The population distribution of O. katoi in its ascidian host did not differ significantly from a random distribution and shrimps inhabiting the same host individual as pairs were found with a frequency similar to that expected by chance alone. This is in contrast to that reported for other socially monogamous crustaceans in which pairs of heterosexual conspecifics are found in host individuals more frequently than expected by chance alone. Thus, the available information argues against monogamy in O. katoi. Furthermore, that a high frequency of solitary females were found brooding embryos and that the sex ratio was skewed toward females suggests that males might be roaming among hosts in search of receptive females in O. katoi. Symbiotic crustaceans can be used as a model system to understand the adaptive value of sexual and mating systems in marine invertebrates. PMID:25799577

  17. Zoonoses in the Mediterranean region.

    PubMed

    Seimenis, Aristarco; Morelli, Daniela; Mantovani, Adriano

    2006-01-01

    The Mediterranean and Middle East Region (MME) is considered the most important area for the historical development and concentration of zoonoses. Besides the classical Mediterranean pattern, an urbanised pattern has emerged which is strongly influenced by globalisation. Both patterns co-exist and have many peculiarities affecting the life cycles of zoonoses and their social impact. The features of those zoonoses which are now most relevant in the MME (brucellosis, rabies, cystic echinococcosis, leishmaniasis, food-borne zoonoses) are discussed. Besides other relevant activities, the World Health Organization has established, since 1979, a specialised programme with a unit coordinating and managing activities: i.e. the Mediterranean Zoonoses Control Centre, operating from Athens, Greece. PMID:17361068

  18. Zoonoses in the Mediterranean region.

    PubMed

    Seimenis, Aristarco; Morelli, Daniela; Mantovani, Adriano

    2006-01-01

    The Mediterranean and Middle East Region (MME) is considered the most important area for the historical development and concentration of zoonoses. Besides the classical Mediterranean pattern, an urbanised pattern has emerged which is strongly influenced by globalisation. Both patterns co-exist and have many peculiarities affecting the life cycles of zoonoses and their social impact. The features of those zoonoses which are now most relevant in the MME (brucellosis, rabies, cystic echinococcosis, leishmaniasis, food-borne zoonoses) are discussed. Besides other relevant activities, the World Health Organization has established, since 1979, a specialised programme with a unit coordinating and managing activities: i.e. the Mediterranean Zoonoses Control Centre, operating from Athens, Greece.

  19. Impact and recovery from a mass mortality event of the gorgonian Paramuricea clavata populations on the french Mediterranean coasts

    NASA Astrophysics Data System (ADS)

    Bonhomme, D.; Garrabou, J.; Perez, T.; Sartoretto, S.; Harmelin, J. G.

    2003-04-01

    An unprecedented mass mortality occurred in the NW Mediterranean in summer 1999. This event affected 30 species of invertebrates from 5 different Phyla (sponges, cnidarians, molluscs, ascidians, bryozoans) on several hundred kilometres of shoreline from the Bay of Genoa in Italy to the Bay of Marseilles in France. The most affected taxa were sponges and cnidarians. This mass mortality took place under an unusual environmental context characterized by high and stable water column temperatures. The impact of the mass mortality and recovery (1999-2002) of populations of the gorgonian Paramuricea clavata from Provence's coasts (France) have been studied. Most surveyed populations displayed 50 % of affected colonies at different degree (dead, severe and low damage), although a great variability in rates of mortality and tissue loss was also evident depending among sites. The mortality impact decreased with depth, a pattern which supports the hypothesis that temperature played a key role in this event. Surveys on populations for which pre-mortality data (density and size structure) was attested that recovery was far from completion three years after the mortality. Considering the growth rate of P. clavata, full recovery of the most affected local populations will take several decades will be necessary to return to pre-mortality values. In the context of the global change and taking into account the correlation with the temperature, one may expect that the frequency of of these kind of events will increase in the next decades. Dramatic consequences can be expected for the conservation of the affected species in shallow habitats, in particular, and for the Mediterranean biodiversity, in general.

  20. Postfire chaparral regeneration under mediterranean and non-mediterranean climates

    USGS Publications Warehouse

    Keeley, Jon E.; Fotheringham, Connie J.; Rundel, Philip W.

    2012-01-01

    This study compares postfire regeneration and diversity patterns in fire-prone chaparral shrublands from mediterranean (California) and non-mediterranean-type climates (Arizona). Vegetation sampling was conducted in tenth hectare plots with nested subplots for the first two years after fire. Floras in the two regions were compared with Jaccard's Index and importance of families and genera compared with dominance-diversity curves. Although there were 44 families in common between the two regions, the dominant families differed; Poaceae and Fabaceae in Arizona and Hydrophyllaceae and Rosaceae in California. Dominance diversity curves indicated in the first year a more equable distribution of families in Arizona than in California. Woody plants were much more dominant in the mediterranean climate and herbaceous plants more dominant in the bimodal rainfall climate. Species diversity was comparable in both regions at the lowest spatial scales but not at the tenth hectare scale. Due to the double growing season in the non-mediterranean region, the diversity for the first year comprised two different herbaceous floras in the fall and spring growing seasons. The Mediterranean climate in California, in contrast, had only a spring growing season and thus the total diversity for the first year was significantly greater in Arizona than in California for both annuals and herbaceous perennials. Chaparral in these two climate regimes share many dominant shrub species but the postfire communities are very different. Arizona chaparral has both a spring and fall growing season and these produce two very different postfire floras. When combined, the total annual diversity was substantially greater in Arizona chaparral.

  1. PON1 and Mediterranean Diet.

    PubMed

    Lou-Bonafonte, José M; Gabás-Rivera, Clara; Navarro, María A; Osada, Jesús

    2015-05-27

    The Mediterranean diet has been proven to be highly effective in the prevention of cardiovascular diseases. Paraoxonase 1 (PON1) has been implicated in the development of those conditions, especially atherosclerosis. The present work describes a systematic review of current evidence supporting the influence of Mediterranean diet and its constituents on this enzyme. Despite the differential response of some genetic polymorphisms, the Mediterranean diet has been shown to exert a protective action on this enzyme. Extra virgin olive oil, the main source of fat, has been particularly effective in increasing PON1 activity, an action that could be due to low saturated fatty acid intake, oleic acid enrichment of phospholipids present in high-density lipoproteins that favor the activity, and increasing hepatic PON1 mRNA and protein expressions induced by minor components present in this oil. Other Mediterranean diet constituents, such as nuts, fruits and vegetables, have been effective in modulating the activity of the enzyme, pomegranate and its compounds being the best characterized items. Ongoing research on compounds isolated from all these natural products, mainly phenolic compounds and carotenoids, indicates that some of them are particularly effective, and this may enhance the use of nutraceuticals and functional foods capable of potentiating PON1 activity.

  2. PON1 and Mediterranean Diet

    PubMed Central

    Lou-Bonafonte, José M.; Gabás-Rivera, Clara; Navarro, María A.; Osada, Jesús

    2015-01-01

    The Mediterranean diet has been proven to be highly effective in the prevention of cardiovascular diseases. Paraoxonase 1 (PON1) has been implicated in the development of those conditions, especially atherosclerosis. The present work describes a systematic review of current evidence supporting the influence of Mediterranean diet and its constituents on this enzyme. Despite the differential response of some genetic polymorphisms, the Mediterranean diet has been shown to exert a protective action on this enzyme. Extra virgin olive oil, the main source of fat, has been particularly effective in increasing PON1 activity, an action that could be due to low saturated fatty acid intake, oleic acid enrichment of phospholipids present in high-density lipoproteins that favor the activity, and increasing hepatic PON1 mRNA and protein expressions induced by minor components present in this oil. Other Mediterranean diet constituents, such as nuts, fruits and vegetables, have been effective in modulating the activity of the enzyme, pomegranate and its compounds being the best characterized items. Ongoing research on compounds isolated from all these natural products, mainly phenolic compounds and carotenoids, indicates that some of them are particularly effective, and this may enhance the use of nutraceuticals and functional foods capable of potentiating PON1 activity. PMID:26024295

  3. Combining environmental suitability and population abundances to evaluate the invasive potential of the tunicate Ciona intestinalis along the temperate South American coast

    PubMed Central

    Estay, Sergio A.; Labra, Fabio A.; Lima, Mauricio

    2015-01-01

    The tunicate Ciona intestinalis is an opportunistic invader with high potential for causing economic losses in aquaculture centers. Recent phylogenetic and population genetic analysis support the existence of a genetic complex described as C. intestinalis with two main dominant species (sp A and B) occurring worldwide. In Chile, the species has been observed around 30°S of latitude, but no official reports exist for the presence of C. intestinalis in southern regions (above 40°S), where most of the mollusk aquaculture centers are located. Here, we used occurrences from multiple invaded regions and extensive field sampling to model and validate the environmental conditions that allow the species to persist and to find the geographic areas with the most suitable environmental conditions for the spread of C. intestinalis in the Chilean coast. By studying the potential expansion of C. intestinalis southward in the Chilean Coast, we aimed to provide valuable information that might help the development of control plans before the species becomes a significant problem, especially above 40°S. Our results highlight that, by using portions of the habitat that are apparently distinguishable, the species seem to be not only genetically distinct, but ecologically distinct as well. The two regional models fitted for sp A and for sp B showed disagreement on which sections of Chilean coastline are considered more suitable for these species. While the model for sp A identifies moderately to highly suitable areas between 30° and 40°S, the model for sp B classifies the areas around 45°S as the most appropriate. Data from field sampling show a positive linear relationship between density of C. intestinalis and the index of suitability for sp A in aquaculture centers. Understanding the relation of the distinct species with the surrounding environment provided valuable insights about probable routes of dispersion in Chile, especially into those areas considered suitable for

  4. Combining environmental suitability and population abundances to evaluate the invasive potential of the tunicate Ciona intestinalis along the temperate South American coast.

    PubMed

    Januario, Stella M; Estay, Sergio A; Labra, Fabio A; Lima, Mauricio

    2015-01-01

    The tunicate Ciona intestinalis is an opportunistic invader with high potential for causing economic losses in aquaculture centers. Recent phylogenetic and population genetic analysis support the existence of a genetic complex described as C. intestinalis with two main dominant species (sp A and B) occurring worldwide. In Chile, the species has been observed around 30°S of latitude, but no official reports exist for the presence of C. intestinalis in southern regions (above 40°S), where most of the mollusk aquaculture centers are located. Here, we used occurrences from multiple invaded regions and extensive field sampling to model and validate the environmental conditions that allow the species to persist and to find the geographic areas with the most suitable environmental conditions for the spread of C. intestinalis in the Chilean coast. By studying the potential expansion of C. intestinalis southward in the Chilean Coast, we aimed to provide valuable information that might help the development of control plans before the species becomes a significant problem, especially above 40°S. Our results highlight that, by using portions of the habitat that are apparently distinguishable, the species seem to be not only genetically distinct, but ecologically distinct as well. The two regional models fitted for sp A and for sp B showed disagreement on which sections of Chilean coastline are considered more suitable for these species. While the model for sp A identifies moderately to highly suitable areas between 30° and 40°S, the model for sp B classifies the areas around 45°S as the most appropriate. Data from field sampling show a positive linear relationship between density of C. intestinalis and the index of suitability for sp A in aquaculture centers. Understanding the relation of the distinct species with the surrounding environment provided valuable insights about probable routes of dispersion in Chile, especially into those areas considered suitable for

  5. Combining environmental suitability and population abundances to evaluate the invasive potential of the tunicate Ciona intestinalis along the temperate South American coast.

    PubMed

    Januario, Stella M; Estay, Sergio A; Labra, Fabio A; Lima, Mauricio

    2015-01-01

    The tunicate Ciona intestinalis is an opportunistic invader with high potential for causing economic losses in aquaculture centers. Recent phylogenetic and population genetic analysis support the existence of a genetic complex described as C. intestinalis with two main dominant species (sp A and B) occurring worldwide. In Chile, the species has been observed around 30°S of latitude, but no official reports exist for the presence of C. intestinalis in southern regions (above 40°S), where most of the mollusk aquaculture centers are located. Here, we used occurrences from multiple invaded regions and extensive field sampling to model and validate the environmental conditions that allow the species to persist and to find the geographic areas with the most suitable environmental conditions for the spread of C. intestinalis in the Chilean coast. By studying the potential expansion of C. intestinalis southward in the Chilean Coast, we aimed to provide valuable information that might help the development of control plans before the species becomes a significant problem, especially above 40°S. Our results highlight that, by using portions of the habitat that are apparently distinguishable, the species seem to be not only genetically distinct, but ecologically distinct as well. The two regional models fitted for sp A and for sp B showed disagreement on which sections of Chilean coastline are considered more suitable for these species. While the model for sp A identifies moderately to highly suitable areas between 30° and 40°S, the model for sp B classifies the areas around 45°S as the most appropriate. Data from field sampling show a positive linear relationship between density of C. intestinalis and the index of suitability for sp A in aquaculture centers. Understanding the relation of the distinct species with the surrounding environment provided valuable insights about probable routes of dispersion in Chile, especially into those areas considered suitable for

  6. A Boolean Function for Neural Induction Reveals a Critical Role of Direct Intercellular Interactions in Patterning the Ectoderm of the Ascidian Embryo.

    PubMed

    Ohta, Naoyuki; Waki, Kana; Mochizuki, Atsushi; Satou, Yutaka

    2015-12-01

    A complex system of multiple signaling molecules often produce differential gene expression patterns in animal embryos. In the ascidian embryo, four signaling ligands, Ephrin-A.d (Efna.d), Fgf9/16/20, Admp, and Gdf1/3-r, coordinately induce Otx expression in the neural lineage at the 32-cell stage. However, it has not been determined whether differential inputs of all of these signaling pathways are really necessary. It is possible that differential activation of one of these signaling pathways is sufficient and the remaining signaling pathways are activated in all cells at similar levels. To address this question, we developed a parameter-free method for determining a Boolean function for Otx expression in the present study. We treated activities of signaling pathways as Boolean values, and we also took all possible patterns of signaling gradients into consideration. We successfully determined a Boolean function that explains Otx expression in the animal hemisphere of wild-type and morphant embryos at the 32-cell stage. This Boolean function was not inconsistent with three sensing patterns, which represented whether or not individual cells received sufficient amounts of the signaling molecules. These sensing patterns all indicated that differential expression of Otx in the neural lineage is primarily determined by Efna.d, but not by differential inputs of Fgf9/16/20, Admp, and Gdf1/3-r signaling. To confirm this hypothesis experimentally, we simultaneously knocked-down Admp, Gdf1/3-r, and Fgf9/16/20, and treated this triple morphant with recombinant bFGF and BMP4 proteins, which mimic Fgf9/16/20 and Admp/Gdf1/3-r activity, respectively. Although no differential inputs of Admp, Gdf1/3-r and Fgf9/16/20 signaling were expected under this experimental condition, Otx was expressed specifically in the neural lineage. Thus, direct cell-cell interactions through Efna.d play a critical role in patterning the ectoderm of the early ascidian embryo. PMID:26714026

  7. A Boolean Function for Neural Induction Reveals a Critical Role of Direct Intercellular Interactions in Patterning the Ectoderm of the Ascidian Embryo.

    PubMed

    Ohta, Naoyuki; Waki, Kana; Mochizuki, Atsushi; Satou, Yutaka

    2015-12-01

    A complex system of multiple signaling molecules often produce differential gene expression patterns in animal embryos. In the ascidian embryo, four signaling ligands, Ephrin-A.d (Efna.d), Fgf9/16/20, Admp, and Gdf1/3-r, coordinately induce Otx expression in the neural lineage at the 32-cell stage. However, it has not been determined whether differential inputs of all of these signaling pathways are really necessary. It is possible that differential activation of one of these signaling pathways is sufficient and the remaining signaling pathways are activated in all cells at similar levels. To address this question, we developed a parameter-free method for determining a Boolean function for Otx expression in the present study. We treated activities of signaling pathways as Boolean values, and we also took all possible patterns of signaling gradients into consideration. We successfully determined a Boolean function that explains Otx expression in the animal hemisphere of wild-type and morphant embryos at the 32-cell stage. This Boolean function was not inconsistent with three sensing patterns, which represented whether or not individual cells received sufficient amounts of the signaling molecules. These sensing patterns all indicated that differential expression of Otx in the neural lineage is primarily determined by Efna.d, but not by differential inputs of Fgf9/16/20, Admp, and Gdf1/3-r signaling. To confirm this hypothesis experimentally, we simultaneously knocked-down Admp, Gdf1/3-r, and Fgf9/16/20, and treated this triple morphant with recombinant bFGF and BMP4 proteins, which mimic Fgf9/16/20 and Admp/Gdf1/3-r activity, respectively. Although no differential inputs of Admp, Gdf1/3-r and Fgf9/16/20 signaling were expected under this experimental condition, Otx was expressed specifically in the neural lineage. Thus, direct cell-cell interactions through Efna.d play a critical role in patterning the ectoderm of the early ascidian embryo.

  8. The Mediterranean is becoming saltier

    NASA Astrophysics Data System (ADS)

    Borghini, M.; Bryden, H.; Schroeder, K.; Sparnocchia, S.; Vetrano, A.

    2014-08-01

    The deep waters of the western Mediterranean Sea have become saltier and warmer for at least the past 40 years at rates of about 0.015 and 0.04 °C per decade. Here we show that two processes contribute to these increases in temperature and salinity. On interannual timescales, deep water formation events in severe winters transmit increasingly salty intermediate waters into the deep water. The second process is a steady downward flux of heat and salt associated with salt finger mixing down through the halocline-thermocline that connects the Levantine Intermediate Water with the deep water. We illustrate these two processes with observations from repeat surveys of the western Mediterranean basin we have made over the past 10 years.

  9. Morbilliviruses in Mediterranean monk seals.

    PubMed

    van de Bildt, M W; Vedder, E J; Martina, B E; Sidi, B A; Jiddou, A B; Ould Barham, M E; Androukaki, E; Komnenou, A; Niesters, H G; Osterhaus, A D

    1999-09-01

    Two morbilliviruses were isolated from Mediterranean monk seals (Monachus monachus), one from a stranded animal in Greece and the other one from carcasses washed ashore during a mass die-off in Mauritania. From both viruses N and P gene fragments were sequenced and compared to those of other known morbilliviruses. The monk seal morbilliviruses most closely resembled previously identified cetacean morbilliviruses, indicating that interspecies transmission from cetaceans to pinnipeds has occurred. PMID:10515264

  10. Evaluation of Cancer Preventive Activity and Structure-Activity Relationships of 3-Demethylubiquinone Q2, Isolated from the Ascidian Aplidium glabrum, and its Synthetic Analogues

    PubMed Central

    Fedorov, Sergey N.; Radchenko, Oleg S.; Shubina, Larisa K.; Balaneva, Nadezhda N.; Bode, Ann M.; Stonik, Valentin A.; Dong, Zigang

    2006-01-01

    Purpose 3-Demethylubiquinone Q2 (1) was isolated from the ascidian Aplidium glabrum. The cancer preventive properties and the structure-activity relationship for 3-demethylubiquinone Q2 (1) and 12 of its synthetic analogues (3–14) are reported. Methods Compounds 3–14, having one or several di- or triprenyl substitutions and quinone moieties with methoxyls in different positions, were synthesized. The cancer preventive properties of compounds 1 and 3–14 were tested in JB6 Cl41 mouse skin cells, using a variety of assessments, including the MTS assay, flow cytometry, and soft agar assay. Statistical nonparametric methods were used to confirm statistical significance. Results All quinones tested were shown to inhibit JB6 Cl41 cell transformation, to induce apoptosis, AP-1 and NF-κB activity, and to inhibit p53 activity. The most promising effects were indicated for compounds containing two isoprene units in a side chain and a methoxyl group at the para-position to a polyprenyl substitution. Conclusions Quinones 1 and 3–14 demonstrated cancer preventive activity in JB6 Cl41 cells, which may be attributed to the induction of p53-independent apoptosis. These activities depended on the length of side chains and on the positions of the methoxyl groups in the quinone part of the molecule. PMID:16320003

  11. Mediterranean Ocean Colour Chlorophyll trend

    NASA Astrophysics Data System (ADS)

    rinaldi, eleonora; colella, simone; santoleri, rosalia

    2014-05-01

    Monitoring chlorophyll (Chl) concentration, seen as a proxy for phytoplankton biomass, is an efficient tool in order to understand the response of marine ecosystem to human pressures. This is particularly important along the coastal regions, in which the strong anthropization and the irrational exploitation of resources represent a persistent threat to the biodiversity. The aim of this work is to assess the effectiveness and feasibility of using Ocean Color (OC) data to monitor the environmental changes in Mediterranean Sea and to develop a method for detecting trend from OC data that can constitute a new indicator of the water quality within the EU Marine Strategy Framework Directive implementation. In this study the Mediterranean merged Case1-Case2 chlorophyll product, produced by CNR-ISAC and distributed in the framework of MyOcean, is analyzed. This product is obtained by using two different bio-optical algorithms for open ocean (Case1) and coastal turbid (Case2) waters; this improves the quality of the Chl satellite estimates, especially near the coast. In order to verify the real capability of the this product for estimating Chl trend and for selecting the most appropriated statistical test to detect trend in the Mediterranean Sea, a comparison between OC and in situ data are carried out. In-situ Chl data are part of the European Environment Information and Observation Network (Eionet) of the European Environmental Agency (EEA). Four different statistical approaches to estimate trend have been selected and used to compare trend values obtained with in-situ and OC data. Results show that the best agreement between in-situ and OC trend is achieved using the Mann- Kendall test. The Mediterranean trend map obtained applying this test to the de-seasonalized OC time series shows that, in accordance with the results of many authors, the case 1 waters of Mediterranean sea are characterized by a negative trend. However, the most intense trend signals, both negative

  12. Plate tectonics of the Mediterranean region.

    PubMed

    McKenzie, D P

    1970-04-18

    The seismicity and fault plane solutions in the Mediterranean area show that two small rapidly moving plates exist in the Eastern Mediterranean, and such plates may be a common feature of contracting ocean basins. The results show that the concepts of plate tectonics apply to instantaneous motions across continental plate boundaries. PMID:16057188

  13. Plate tectonics of the Mediterranean region.

    PubMed

    McKenzie, D P

    1970-04-18

    The seismicity and fault plane solutions in the Mediterranean area show that two small rapidly moving plates exist in the Eastern Mediterranean, and such plates may be a common feature of contracting ocean basins. The results show that the concepts of plate tectonics apply to instantaneous motions across continental plate boundaries.

  14. Hydrothermalism in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Dando, P. R.; Stüben, D.; Varnavas, S. P.

    1999-08-01

    Hydrothermalism in the Mediterranean Sea results from the collision of the African and European plates, with the subduction of the oceanic part of the African plate below Europe. High heat flows in the resulting volcanic arcs and back-arc extensional areas have set-up hydrothermal convection systems. Most of the known hydrothermal sites are in shallow coastal waters, <200 m depth, so that much of the reported fluid venting is of the gasohydrothermal type. The hydrothermal liquids are of varying salinities, both because of phase separation as a result of seawater boiling at the low pressures and because of significant inputs of rainfall into the hydrothermal reservoirs at some sites. The major component of the vented gas is carbon dioxide, with significant quantities of sulphur dioxide, hydrogen sulphide, methane and hydrogen also being released. Acid leaching of the underlying rocks leads to the mobilisation of heavy metals, many of which are deposited sub-surface although there is a conspicuous enrichment of metals in surficial sediments in venting areas. Massive polymetalic sulphides have been reported from some sites. No extant vent-specific fauna have been described from Mediterranean sites. There is a reduced diversity of fauna within the sediments at the vents. In contrast, a high diversity of epifauna has been reported and the vent sites are areas of settlement for exotic thermophilic species. Large numbers of novel prokaryotes, especially hyperthermophilic crenarchaeota, have been isolated from Mediterranean hydrothermal vents. However, their distribution in the subsurface biosphere and their role in the biogeochemistry of the sites has yet to be studied.

  15. Mediterranean diets: are they environmentally responsible?

    PubMed

    Gussow, J D

    1995-06-01

    Dietary recommendations made to promote health seldom, if ever, take account of environmental implications of producing recommended foods. This paper considers several aspects of the traditional Mediterranean diet in relation to global sustainability. Plant-centered diets, such as those consumed around the Mediterranean Sea during the 1950s and 1960s, would be environmentally beneficial because they imply need for a much smaller population of domestic animals and, consequently, lowered demand on soil, water, and energy resources. Although fish consumption is high in some Mediterranean diets, fish should not be used to replace animal flesh because all of the world's major fisheries are currently overexploited. As for the appropriateness of Mediterranean fresh fruit and vegetables (which would need to be imported into non-Mediterranean regions), locally producible substitutes should be used wherever possible to reduce the environmental costs of transporting food great distances. Research is needed to examine the environmental consequences of certain exports such as olive oil.

  16. The occurrence of the colonial ascidian Didemnum sp. on Georges Bank gravel habitat: ecological observations and potential effects on groundfish and scallop fisheries

    USGS Publications Warehouse

    Valentine, P.C.; Collie, J.S.; Reid, R.N.; Asch, R.G.; Guida, V.G.; Blackwood, D.S.

    2007-01-01

    The colonial ascidian Didemnum sp. is present on the Georges Bank fishing grounds in a gravel habitat where the benthic invertebrate fauna has been monitored annually since 1994. The species was not noted before 2002 when large colonies were first observed; and by 2003 and 2004 it covered large areas of the seabed at some locations. The latest survey in 2005 documented the tunicate's presence in two gravel areas that total more than 67 nm2 (230 km2). The affected area is located on the Northern Edge of the bank in United States waters near the U.S./Canada boundary ( Fig. 1). This is the first documented offshore occurrence of a species that has colonized eastern U.S. coastal waters from New York to Maine during the past 15–20 years ( U.S. Geological Survey, 2006). Video imagery shows colonies coalescing to form large mats that cover more than 50% of the seabed along some video/photo transects. The affected area is an immobile pebble and cobble pavement that lies at water depths of 40 to 65 m where strong semidiurnal tidal currents reach speeds of 1 to 2 kt (50–100 cm/s). The water column is mixed year round, ensuring a constant supply of nutrients to the seabed. Annual temperatures range from 4 to 15 °C ( Mountain and Holzwarth, 1989). The gravel areas are bounded by sand ridges whose mobile surfaces are moved daily by the strong tidal currents. Studies commenced here in 1994 to characterize the gravel habitat and to document the effects of fishing disturbance on it ( Collie et al., 2005).

  17. The colonial ascidian Didemnum sp. A: current distribution, basic biology and potential threat to marine communities of the northeast and west coasts of North America

    USGS Publications Warehouse

    Bullard, S.G.; Lambert, G.; Carman, M.R.; Byrnes, J.; Whitlatch, R.B.; Ruiz, G.; Miller, R.J.; Harris, L.; Valentine, P.C.; Collie, J.S.; Pederson, J.; McNaught, D.C.; Cohen, A.N.; Asch, R.G.; Dijkstra, J.; Heinonen, K.

    2007-01-01

    Didemnum sp. A is a colonial ascidian with rapidly expanding populations on the east and west coasts of North America. The origin of Didemum sp. A is unknown. Populations were first observed on the northeast coast of the U.S. in the late 1980s and on the west coast during the 1990s. It is currently undergoing a massive population explosion and is now a dominant member of many subtidal communities on both coasts. To determine Didemnum sp. A's current distribution, we conducted surveys from Maine to Virginia on the east coast and from British Columbia to southern California on the west coast of the U.S. between 1998 and 2005. In nearshore locations Didemnum sp. A currently ranges from Eastport, Maine to Shinnecock Bay, New York on the east coast. On the west coast it has been recorded from Humboldt Bay to Port San Luis in California, several sites in Puget Sound, Washington, including a heavily fouled mussel culture facility, and several sites in southwestern British Columbia on and adjacent to oyster and mussel farms. The species also occurs at deeper subtidal sites (up to 81 m) off New England, including Georges, Stellwagen and Tillies Banks. On Georges Bank numerous sites within a 230 km2 area are 50–90% covered by Didemnum sp. A; large colonies cement the pebble gravel into nearly solid mats that may smother infaunal organisms. These observations suggest that Didemnum sp. A has the potential to alter marine communities and affect economically important activities such as fishing and aquaculture.

  18. Effects of Extreme Climate on Mediterranean Societies

    NASA Astrophysics Data System (ADS)

    Xoplaki, Elena

    2009-04-01

    Climate Extremes During Recent Millennia and Their Impact on Mediterranean Societies; Athens, Greece, 13-16 September 2008; Climatic extremes in the past few thousand years have severely affected societies throughout the Mediterranean region and have changed the outcome of historical events in some instances. Climatic extremes—droughts, floods, prolonged cold and heat—affect society in a variety of ways, operating through famine, disease, and social upheaval. These topics were discussed at an interdisciplinary symposium at the National and Kapodistrian University, in Greece, that brought together climatologists, paleoclimatologists, anthropologists, geologists, archaeologists, and historians working in the greater Mediterranean region.

  19. Foreword: Mediterranean diet and climatic change.

    PubMed

    Serra-Majem, Lluís; Bach-Faig, Anna; Miranda, Gemma; Clapes-Badrinas, Carmen

    2011-12-01

    Changes in diet, reducing animal products and increasing consumption of vegetables can not only benefit human health and the overall use of land, but can also play a decisive role in the politics of climate change mitigation. In this sense, the Mediterranean diet (MD) is presented as a sustainable cultural model, respectful of the environment, whose adherence in Mediterranean countries should contribute to mitigating climate change. The recognition of the MD as an Intangible Cultural Heritage of Humanity by UNESCO in 2010 obliges the Mediterranean Diet Foundation to continue waging this recovery process and to promote our ancient food traditions in a prism of sustainability and commitment to the environment.

  20. Metagenomes of Mediterranean Coastal Lagoons

    PubMed Central

    Ghai, Rohit; Hernandez, Claudia Mella; Picazo, Antonio; Mizuno, Carolina Megumi; Ininbergs, Karolina; Díez, Beatriz; Valas, Ruben; DuPont, Christopher L.; McMahon, Katherine D.; Camacho, Antonio; Rodriguez-Valera, Francisco

    2012-01-01

    Coastal lagoons, both hypersaline and freshwater, are common, but still understudied ecosystems. We describe, for the first time, using high throughput sequencing, the extant microbiota of two large and representative Mediterranean coastal lagoons, the hypersaline Mar Menor, and the freshwater Albufera de Valencia, both located on the south eastern coast of Spain. We show there are considerable differences in the microbiota of both lagoons, in comparison to other marine and freshwater habitats. Importantly, a novel uncultured sulfur oxidizing Alphaproteobacteria was found to dominate bacterioplankton in the hypersaline Mar Menor. Also, in the latter prokaryotic cyanobacteria were almost exclusively comprised by Synechococcus and no Prochlorococcus was found. Remarkably, the microbial community in the freshwaters of the hypertrophic Albufera was completely in contrast to known freshwater systems, in that there was a near absence of well known and cosmopolitan groups of ultramicrobacteria namely Low GC Actinobacteria and the LD12 lineage of Alphaproteobacteria. PMID:22778901

  1. Familial Mediterranean fever: current perspectives.

    PubMed

    Sönmez, Hafize Emine; Batu, Ezgi Deniz; Özen, Seza

    2016-01-01

    Familial Mediterranean fever (FMF) is the most frequent monogenic autoinflammatory disease, and it is characterized by recurrent attacks of fever and polyserositis. The disease is associated with mutations in the MEFV gene encoding pyrin, which causes exaggerated inflammatory response through uncontrolled production of interleukin 1. The major long-term complication of FMF is amyloidosis. Colchicine remains the principle therapy, and the aim of treatment is to prevent acute attacks and the consequences of chronic inflammation. With the evolution in the concepts about the etiopathogenesis and genetics of the disease, we have understood that FMF is more complicated than an ordinary autosomal recessive monogenic disorder. Recently, recommendation sets have been generated for interpretation of genetic testing and genetic diagnosis of FMF. Here, we have reviewed the current perspectives in FMF in light of recent recommendations. PMID:27051312

  2. Metagenomes of Mediterranean coastal lagoons.

    PubMed

    Ghai, Rohit; Hernandez, Claudia Mella; Picazo, Antonio; Mizuno, Carolina Megumi; Ininbergs, Karolina; Díez, Beatriz; Valas, Ruben; DuPont, Christopher L; McMahon, Katherine D; Camacho, Antonio; Rodriguez-Valera, Francisco

    2012-01-01

    Coastal lagoons, both hypersaline and freshwater, are common, but still understudied ecosystems. We describe, for the first time, using high throughput sequencing, the extant microbiota of two large and representative Mediterranean coastal lagoons, the hypersaline Mar Menor, and the freshwater Albufera de Valencia, both located on the south eastern coast of Spain. We show there are considerable differences in the microbiota of both lagoons, in comparison to other marine and freshwater habitats. Importantly, a novel uncultured sulfur oxidizing Alphaproteobacteria was found to dominate bacterioplankton in the hypersaline Mar Menor. Also, in the latter prokaryotic cyanobacteria were almost exclusively comprised by Synechococcus and no Prochlorococcus was found. Remarkably, the microbial community in the freshwaters of the hypertrophic Albufera was completely in contrast to known freshwater systems, in that there was a near absence of well known and cosmopolitan groups of ultramicrobacteria namely Low GC Actinobacteria and the LD12 lineage of Alphaproteobacteria.

  3. Familial Mediterranean fever: current perspectives

    PubMed Central

    Sönmez, Hafize Emine; Batu, Ezgi Deniz; Özen, Seza

    2016-01-01

    Familial Mediterranean fever (FMF) is the most frequent monogenic autoinflammatory disease, and it is characterized by recurrent attacks of fever and polyserositis. The disease is associated with mutations in the MEFV gene encoding pyrin, which causes exaggerated inflammatory response through uncontrolled production of interleukin 1. The major long-term complication of FMF is amyloidosis. Colchicine remains the principle therapy, and the aim of treatment is to prevent acute attacks and the consequences of chronic inflammation. With the evolution in the concepts about the etiopathogenesis and genetics of the disease, we have understood that FMF is more complicated than an ordinary autosomal recessive monogenic disorder. Recently, recommendation sets have been generated for interpretation of genetic testing and genetic diagnosis of FMF. Here, we have reviewed the current perspectives in FMF in light of recent recommendations. PMID:27051312

  4. Mediterranean Ocean Colour Chlorophyll Trends.

    PubMed

    Colella, Simone; Falcini, Federico; Rinaldi, Eleonora; Sammartino, Michela; Santoleri, Rosalia

    2016-01-01

    In being at the base of the marine food web, phytoplankton is particularly important for marine ecosystem functioning (e.g., biodiversity). Strong anthropization, over-exploitation of natural resources, and climate change affect the natural amount of phytoplankton and, therefore, represent a continuous threat to the biodiversity in marine waters. In particular, a concerning risks for coastal waters is the increase in nutrient inputs of terrestrial/anthropogenic origin that can lead to undesirable modifications of phytoplankton concentration (i.e., eutrophication). Monitoring chlorophyll (Chl) concentration, which is a proxy of phytoplankton biomass, is an efficient tool for recording and understanding the response of the marine ecosystem to human pressures and thus for detecting eutrophication. Here, we compute Chl trends over the Mediterranean Sea by using satellite data, also highlighting the fact that remote sensing may represent an efficient and reliable solution to synoptically control the "good environmental status" (i.e., the Marine Directive to achieve Good Environmental Status of EU marine waters by 2020) and to assess the application of international regulations and environmental directives. Our methodology includes the use of an ad hoc regional (i.e., Mediterranean) algorithm for Chl concentration retrieval, also accounting for the difference between offshore (i.e., Case I) and coastal (i.e., Case II) waters. We apply the Mann-Kendall test and the Sens's method for trend estimation to the Chl concentration de-seasonalized monthly time series, as obtained from the X-11 technique. We also provide a preliminary analysis of some particular trends by evaluating their associated inter-annual variability. The high spatial resolution of our approach allows a clear identification of intense trends in those coastal waters that are affected by river outflows. We do not attempt to attribute the observed trends to specific anthropogenic events. However, the trends

  5. Mediterranean Ocean Colour Chlorophyll Trends

    PubMed Central

    Colella, Simone; Falcini, Federico; Rinaldi, Eleonora; Sammartino, Michela; Santoleri, Rosalia

    2016-01-01

    In being at the base of the marine food web, phytoplankton is particularly important for marine ecosystem functioning (e.g., biodiversity). Strong anthropization, over-exploitation of natural resources, and climate change affect the natural amount of phytoplankton and, therefore, represent a continuous threat to the biodiversity in marine waters. In particular, a concerning risks for coastal waters is the increase in nutrient inputs of terrestrial/anthropogenic origin that can lead to undesirable modifications of phytoplankton concentration (i.e., eutrophication). Monitoring chlorophyll (Chl) concentration, which is a proxy of phytoplankton biomass, is an efficient tool for recording and understanding the response of the marine ecosystem to human pressures and thus for detecting eutrophication. Here, we compute Chl trends over the Mediterranean Sea by using satellite data, also highlighting the fact that remote sensing may represent an efficient and reliable solution to synoptically control the “good environmental status” (i.e., the Marine Directive to achieve Good Environmental Status of EU marine waters by 2020) and to assess the application of international regulations and environmental directives. Our methodology includes the use of an ad hoc regional (i.e., Mediterranean) algorithm for Chl concentration retrieval, also accounting for the difference between offshore (i.e., Case I) and coastal (i.e., Case II) waters. We apply the Mann-Kendall test and the Sens’s method for trend estimation to the Chl concentration de-seasonalized monthly time series, as obtained from the X-11 technique. We also provide a preliminary analysis of some particular trends by evaluating their associated inter-annual variability. The high spatial resolution of our approach allows a clear identification of intense trends in those coastal waters that are affected by river outflows. We do not attempt to attribute the observed trends to specific anthropogenic events. However, the

  6. [Mediterranean diet. Characteristics and health benefits].

    PubMed

    Serra Majem, Lluís; García Alvarez, Alicia; Ngo de la Cruz, Joy

    2004-06-01

    The purpose of this article is to define the concept of Mediterranean Diet or Diets and to describe the associated health benefits recognised by the scientific community. The characteristics of the Mediterranean Diet are described as well as the effects the foods comprising it have on the most common pathologies such as cardiovascular disease and cancer. The Spanish Society of Community Nutrition's consensus based Healthy Diet Pyramid, along with Greece's pyramid for food guidelines for the adult population (from the Greek Ministry of Health), are presented and compared. They are the graphic representation of the food and physical activity guides of two typically Mediterranean countries. Nutritional and sociological trends are also discussed and their impact on the evolution of the Mediterranean Diet. PMID:15584472

  7. Night Views Over the Mediterranean Sea

    NASA Video Gallery

    This video over the Mediterranean Sea was taken by the crew of Expedition 29 aboard the International Space Station. This sequence of shots was taken on Oct. 6, 2011, from 22:58:09 to 23:13:15 GMT,...

  8. The Eratosthenes Seamount - Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Ehrhardt, A.; Schnabel, M.; Damm, V.

    2012-04-01

    The Eratosthenes Seamount forms a prominent landmark in the Eastern Mediterranean. It is located south of Cyprus with the Levantine Basin on its eastern side, the Herodotus Basin on its western side and the Nile Cone south of the seamount. The Eratosthenes Seamount rises up to 750 m below sea surface and is about 1200 m higher than the surrounding seafloor of the Levantine Basin and the Nile Cone sediments. The Eratosthenes Seamount is considered as a continental fragment of the former African-Nubian Plate that was rifted to its present position relative to Africa during the formation of the Tethyan Ocean. In 2010 a detailed geophysical survey was carried out in the area of the Eratosthenes Seamount by the Federal Institute for Geosciences and Natural Resources of Germany including multichannel seismic (MCS), refraction seismics, magnetic, gravity and magnetotelluric data acquisition. First results show a highly deformed seamount, with a plateau-like top that is impacted by west-east trending graben formation. The slopes of the seamount are eroded showing deep incised ripple patterns and recent submarine landslides. The Eratosthenes Seamount produces also a prominent magnetic and gravity anomaly, both supporting its uniqueness in the area of the Eastern Mediterranean. Velocity information by refraction seismic modeling, as well as the models of the magnetic and gravity data show evidence for a volcanic core of the seamount with carbonate layers on top of the volcanic core. The slopes of the seamount terminate against a conspicuous rim-like escarpment that forms in addition the northern and western termination of the Messinian Evaporites in the study area. The MCS and refraction seismic data show a very deep Levantine Basin with maximum acoustic basement depths of 12 to 14 km very close to the slope of the Eratosthenes Seamount. The deepest sediments resolved by the MCS data are of Lower Cretaceous to Jurassic age. The refraction seismic model shows a 14 km thick

  9. Atlantic forcing of the Mediterranean oligotrophy

    NASA Astrophysics Data System (ADS)

    Huertas, I. E.; RíOs, A. F.; GarcíA-Lafuente, J.; Navarro, G.; Makaoui, A.; SáNchez-RomáN, A.; Rodriguez-Galvez, S.; Orbi, A.; RuíZ, J.; PéRez, F. F.

    2012-06-01

    The Mediterranean Sea shows a peculiar anomaly in its nutrient pattern compared to the global ocean, as there is decrease in nutrient concentration from west to east. This feature has been attributed to the antiestuarine circulation at the Strait of Gibraltar, where an eastward flow of Atlantic nutrient-poor surface waters is compensated by a westward countercurrent of Mediterranean nutrient-rich deep waters. This water exchange has been suggested as the ultimate cause for the oligotrophy of the Mediterranean basin, even though only a few studies have accurately examined the magnitude of the nutrient flux through the Strait of Gibraltar. In this work, data from the Gibraltar Fixed Time series (GIFT) between 2005 and 2008 were used to assess nutrient distributions. Applying a two-layer model of water mass exchange and using the Mediterranean outflow recorded in situ, the net export of nutrients from the Mediterranean to the Atlantic was calculated as 139 and 4.8 Gmol yr-1 of nitrate and phosphate, respectively. The results also demonstrated that the Atlantic inflow is not nutrient depleted and in particular contains significant levels of phosphate, which is the limiting factor for biological productivity in the eastern Mediterranean. The distribution of the quasi-conservative parameter N* in the western and eastern basins indicated that nitrate-deficient surface waters are transformed into phosphate-deficient bottom waters by internal cycling processes. Therefore, phosphate depletion in the Mediterranean does not have its origin in the entry of a phosphorus-impoverished Atlantic inflow through the Strait of Gibraltar.

  10. Mediterranean milk and milk products.

    PubMed

    Hinrichs, Jörg

    2004-03-01

    Milk and dairy products are part of a healthy Mediterranean diet which, besides cow's milk, also consists of sheep's, goat's and buffalo's milk--alone or as a mixture---as raw material. The fat and protein composition of the milk of the various animal species differs only slightly, but in every case it has a high priority in human nutrition. The milk proteins are characterized by a high content of essential amino acids. Beyond that macromolecules,which have various biological functions, are available or may be formed by proteolysis in milk. Taking this into consideration, the technology of different well-known Italian and German cheese types is presented and the differences as well as correspondences regarding nutrition are discussed. Especially Ricotta and Mascarpone are discussed in detail. Ricotta represents a special feature as this cheese is traditionally made of whey and cream. Thus the highly valuable whey proteins which contain a higher amount of the amino acids lysine, methionine and cysteic acid in comparison to casein and, additionally, to soy protein, are made usable for human nutrition. Finally, it is pointed out on the basis of individual examples that technologies to enrich whey proteins in cheese are already available and in use. Thus, the flavor of low fat cheese is improved and the nutritional value is increased. PMID:15052494

  11. Myxozoan infections in Mediterranean mariculture.

    PubMed

    Palenzuela, O

    2006-06-01

    Fish mariculture has dramatically expanded in recent years in Mediterranean countries. In this scenario, several pathological problems have logically arisen and parasitological etiologies are increasingly being reported, either as primary or secondary pathogens. Myxozoa is the most diverse and economically important group of fish parasites, and several species are known to cause or contribute to losses in mariculture. Species of the genus Enteromyxum currently constitute the most serious parasitological threat. Some unusual biological characters, such as wide host spectrum and direct fish-to-fish transmission, together with high virulence for some host species, combine a dangerous cocktail which is emerging in recent years. Closed-system (recirculation) and heated-water locations are especially sensitive to chronic infections by these parasites, which can cause serious mortality and even discourage culture of some fish species at certain locations (i.e, Diplodus puntazzo). The presentation presents an overview of recent advances in research of marine myxozoans, focusing mainly in the most pathogenic, Enteromyxum spp. The incidence of these and other emerging infections, and the design of potential strategies for control will be introduced. PMID:16881390

  12. Seasonality of Arctic Mediterranean Exchanges

    NASA Astrophysics Data System (ADS)

    Rieper, Christoph; Quadfasel, Detlef

    2015-04-01

    The Arctic Mediterranean communicates through a number of passages with the Atlantic and the Pacific Oceans. Most of the volume exchange happens at the Greenland-Scotland-Ridge: warm and saline Atlantic Water flows in at the surface, cold, dense Overflow Water flows back at the bottom and fresh and cold Polar Water flows out along the East Greenland coast. All surface inflows show a seasonal signal whereas only the outflow through the Faroe Bank Channel exhibits significant seasonality. Here we present a quantification of the seasonal cycle of the exchanges across the Greenland-Scotland ridge based on volume estimates of the in- and outflows within the last 20 years (ADCP and altimetry). Our approach is comparatistic: we compare different properties of the seasonal cycle like the strength or the phase between the different in- and outflows. On the seasonal time scale the in- and outflows across the Greenland-Scotland-Ridge are not balanced. The net flux thus has to be balanced by the other passages on the Canadian Archipelago, Bering Strait as well as runoff from land.

  13. Metabolic acceleration in Mediterranean Perciformes

    NASA Astrophysics Data System (ADS)

    Lika, Konstadia; Kooijman, Sebastiaan A. L. M.; Papandroulakis, Nikos

    2014-11-01

    Larval stages are considered the most critical of fish development. During a very short period of time (2 to 3 months), larvae undergo major morphoanatomical and functional changes in order to transform into juveniles while remaining functioning (developing, eating, surviving). Depending on species and environmental conditions, patterns in larval development may vary. We study the patterns of larval development for nine fish species of Perciformes reared under aquaculture conditions and compare them in terms of species-specific parameters derived from DEB theory. We extended the standard DEB model to include metabolic acceleration during the larval period, where maximum specific assimilation and energy conductance increase with length between birth and metabolic metamorphosis. Metabolic acceleration has as a consequence that larvae initially grow slower than juveniles and adults. Our results indicate that the species with higher acceleration have lower growth rates at birth and they also suggest that metabolic acceleration is related to spawning season. High metabolic acceleration of demersal species is associated with summer-autumn spawning in the Mediterranean, where temperature is high and food availability is low.

  14. Woodlands Grazing Issues in Mediterranean Basin

    NASA Astrophysics Data System (ADS)

    Campos, P.

    2009-04-01

    In Mediterranean basin, woodlands grazing still continue to be important commercial owners' benefits. These owners manage woodlands vegetations as if they were not at risk of degradation and declining. Frequently, no temporally grazing set-aside is taken into account to avoid overgrazing of annual and perennial vegetations. Although less common, in the northern shore of Mediterranean basin undergrazing might increase the frequency and the number of catastrophic forest fires. This under/over grazing regime occurs in the Mediterranean basin woodlands with contrasted differences on land property rights, local economies and government livestock policy incentives. Spain and Tunisia are examples of these Mediterranean livestock contrasts. Most of Spanish Mediterranean woodlands and livestock herds are large private ownerships and owners could maintain their lands and livestock herds properties on the basis of moderate cash-income compensation against land revaluation and exclusive amenity self-consumption. The later is less tangible benefit and it could include family land legacy, nature enjoyment, country stile of life development, social status and so on. In public woodlands, social and environmental goals -as they are cultural heritage, biodiversity loss mitigation, soil conservation and employment- could maintain market unprofitable woodlands operations. Last three decades Spanish Mediterranean woodlands owners have increased the livestock herds incentivized by government subsidies. As result, grazing rent is pending on the level of European Union and Spanish government livestock subsidies. In this context, Spanish Mediterranean woodlands maintain a high extensive livestock stoking population, which economy could be called fragile and environmentally unsustainable because forest degradation and over/under grazing practices. Tunisian Mediterranean woodlands are state properties and livestock grazing is practice as a free private regimen. Livestock herds are small herd

  15. Mediterranean Diet, Caffeine May Be Good for Your Eyes

    MedlinePlus

    ... medlineplus.gov/news/fullstory_161598.html Mediterranean Diet, Caffeine May Be Good for Your Eyes Study found ... HealthDay News) -- Eating a Mediterranean diet and consuming caffeine may lower your chances of developing age-related ...

  16. Mediterranean diet, culture and heritage: challenges for a new conception.

    PubMed

    Xavier Medina, F

    2009-09-01

    The aim of the present article is to discuss the role of the Mediterranean diet as a part of Human Culture and Intangible Cultural Heritage. Until the present, Mediterranean diet has been observed as a healthy model of medical behaviour. After its proposal as a Cultural Heritage of the Humanity at UNESCO (United Nations Educational, Scientific and Cultural Organization), Mediterranean diet is actually being observed as a part of Mediterranean culture and starting its concept as an equivalent of Mediterranean Cultural Food System or Mediterranean Culinary System. At the candidacy of Mediterranean diet as a World Cultural Intangible Heritage to be presented at UNESCO in 2008, this new conception is making sense. A new point of view that will be capital in the future discussions about the Mediterranean diet, their challenges and their future perspectives.

  17. The dynamical structure of intense Mediterranean cyclones

    NASA Astrophysics Data System (ADS)

    Flaounas, Emmanouil; Raveh-Rubin, Shira; Wernli, Heini; Drobinski, Philippe; Bastin, Sophie

    2015-05-01

    This paper presents and analyzes the three-dimensional dynamical structure of intense Mediterranean cyclones. The analysis is based on a composite approach of the 200 most intense cyclones during the period 1989-2008 that have been identified and tracked using the output of a coupled ocean-atmosphere regional simulation with 20 km horizontal grid spacing and 3-hourly output. It is shown that the most intense Mediterranean cyclones have a common baroclinic life cycle with a potential vorticity (PV) streamer associated with an upper-level cyclonic Rossby wave breaking, which precedes cyclogenesis in the region and triggers baroclinic instability. It is argued that this common baroclinic life cycle is due to the strongly horizontally sheared environment in the Mediterranean basin, on the poleward flank of the quasi-persistent subtropical jet. The composite life cycle of the cyclones is further analyzed considering the evolution of key atmospheric elements as potential temperature and PV, as well as the cyclones' thermodynamic profiles and rainfall. It is shown that most intense Mediterranean cyclones are associated with warm conveyor belts and dry air intrusions, similar to those of other strong extratropical cyclones, but of rather small scale. Before cyclones reach their mature stage, the streamer's role is crucial to advect moist and warm air towards the cyclones center. These dynamical characteristics, typical for very intense extratropical cyclones in the main storm track regions, are also valid for these Mediterranean cases that have features that are visually similar to tropical cyclones.

  18. Variation in the composition of corals, fishes, sponges, echinoderms, ascidians, molluscs, foraminifera and macroalgae across a pronounced in-to-offshore environmental gradient in the Jakarta Bay-Thousand Islands coral reef complex.

    PubMed

    Cleary, D F R; Polónia, A R M; Renema, W; Hoeksema, B W; Rachello-Dolmen, P G; Moolenbeek, R G; Budiyanto, A; Yahmantoro; Tuti, Y; Giyanto; Draisma, S G A; Prud'homme van Reine, W F; Hariyanto, R; Gittenberger, A; Rikoh, M S; de Voogd, N J

    2016-09-30

    Substrate cover, water quality parameters and assemblages of corals, fishes, sponges, echinoderms, ascidians, molluscs, benthic foraminifera and macroalgae were sampled across a pronounced environmental gradient in the Jakarta Bay-Thousand Islands reef complex. Inshore sites mainly consisted of sand, rubble and turf algae with elevated temperature, dissolved oxygen, pH and chlorophyll concentrations and depauperate assemblages of all taxa. Live coral cover was very low inshore and mainly consisted of sparse massive coral heads and a few encrusting species. Faunal assemblages were more speciose and compositionally distinct mid- and offshore compared to inshore. There were, however, small-scale differences among taxa. Certain midshore sites, for example, housed assemblages resembling those typical of the inshore environment but this differed depending on the taxon. Substrate, water quality and spatial variables together explained from 31% (molluscs) to 72% (foraminifera) of the variation in composition. In general, satellite-derived parameters outperformed locally measured parameters.

  19. Preliminary study on the occurrence of brominated organic compounds in Dutch marine organisms.

    PubMed

    Kotterman, Michiel; van der Veen, Ike; van Hesselingen, Judith; Leonards, Pim; Osinga, Ronald; de Boer, Jacob

    2003-07-01

    The extracts of three marine organisms; the ascidian Ciona intestinalis, the brown seaweed Sargassum muticum and the sponge Halichondria panicea, all elicited a number of brominated compounds, some of which were tentatively identified. Tribromophenol was observed in all species. This compound, also industrially produced as flame retardant and fungicide, was likely due to endogenous production. PMID:12919829

  20. Influence of Mediterranean Outflow on climate

    NASA Astrophysics Data System (ADS)

    Rahmstorf, Stefan

    A cover article in Eos last year [Johnson, 1997] called for a dam across the Strait of Gibraltar to prevent a new Ice Age. In this article, R. G. Johnson argued that reduced Nile River flow after building the Aswan Dam increases Mediterranean Sea salinity, leading to enhanced outflow of salty water into the Atlantic Ocean. This, in turn, would alter the thermohaline (that is, temperature and salinity driven) circulation of the Atlantic, heat up the Labrador Sea and enhance evaporation there, and increase snowfall in Canada until a new ice sheet builds up. Ocean circulation model experiments, however, suggest that this fear is unfounded. While Mediterranean saltwater outflow (Figure 1a) does appear to have some effect on North Atlantic circulation and surface climate, the change in Mediterranean salt budget resulting from the Aswan Dam is far too small to have any noticeable impact.

  1. Decreasing Fires in Mediterranean Europe.

    PubMed

    Turco, Marco; Bedia, Joaquín; Di Liberto, Fabrizio; Fiorucci, Paolo; von Hardenberg, Jost; Koutsias, Nikos; Llasat, Maria-Carmen; Xystrakis, Fotios; Provenzale, Antonello

    2016-01-01

    Forest fires are a serious environmental hazard in southern Europe. Quantitative assessment of recent trends in fire statistics is important for assessing the possible shifts induced by climate and other environmental/socioeconomic changes in this area. Here we analyse recent fire trends in Portugal, Spain, southern France, Italy and Greece, building on a homogenized fire database integrating official fire statistics provided by several national/EU agencies. During the period 1985-2011, the total annual burned area (BA) displayed a general decreasing trend, with the exception of Portugal, where a heterogeneous signal was found. Considering all countries globally, we found that BA decreased by about 3020 km2 over the 27-year-long study period (i.e. about -66% of the mean historical value). These results are consistent with those obtained on longer time scales when data were available, also yielding predominantly negative trends in Spain and France (1974-2011) and a mixed trend in Portugal (1980-2011). Similar overall results were found for the annual number of fires (NF), which globally decreased by about 12600 in the study period (about -59%), except for Spain where, excluding the provinces along the Mediterranean coast, an upward trend was found for the longer period. We argue that the negative trends can be explained, at least in part, by an increased effort in fire management and prevention after the big fires of the 1980's, while positive trends may be related to recent socioeconomic transformations leading to more hazardous landscape configurations, as well as to the observed warming of recent decades. We stress the importance of fire data homogenization prior to analysis, in order to alleviate spurious effects associated with non-stationarities in the data due to temporal variations in fire detection efforts. PMID:26982584

  2. Decreasing Fires in Mediterranean Europe.

    PubMed

    Turco, Marco; Bedia, Joaquín; Di Liberto, Fabrizio; Fiorucci, Paolo; von Hardenberg, Jost; Koutsias, Nikos; Llasat, Maria-Carmen; Xystrakis, Fotios; Provenzale, Antonello

    2016-01-01

    Forest fires are a serious environmental hazard in southern Europe. Quantitative assessment of recent trends in fire statistics is important for assessing the possible shifts induced by climate and other environmental/socioeconomic changes in this area. Here we analyse recent fire trends in Portugal, Spain, southern France, Italy and Greece, building on a homogenized fire database integrating official fire statistics provided by several national/EU agencies. During the period 1985-2011, the total annual burned area (BA) displayed a general decreasing trend, with the exception of Portugal, where a heterogeneous signal was found. Considering all countries globally, we found that BA decreased by about 3020 km2 over the 27-year-long study period (i.e. about -66% of the mean historical value). These results are consistent with those obtained on longer time scales when data were available, also yielding predominantly negative trends in Spain and France (1974-2011) and a mixed trend in Portugal (1980-2011). Similar overall results were found for the annual number of fires (NF), which globally decreased by about 12600 in the study period (about -59%), except for Spain where, excluding the provinces along the Mediterranean coast, an upward trend was found for the longer period. We argue that the negative trends can be explained, at least in part, by an increased effort in fire management and prevention after the big fires of the 1980's, while positive trends may be related to recent socioeconomic transformations leading to more hazardous landscape configurations, as well as to the observed warming of recent decades. We stress the importance of fire data homogenization prior to analysis, in order to alleviate spurious effects associated with non-stationarities in the data due to temporal variations in fire detection efforts.

  3. Dsp in Moroccan Mediterranean Sea.

    NASA Astrophysics Data System (ADS)

    Rachid, Fadel

    At sea temperate, there is usually a sole major floraison of the phytoplancton (in the spring) that exhausts the available stock of nutritious salt. This phenomenon is natural. It's more known under the name of "red tide or colored waters", it brings about a danger, with hazardous consequences on the wildlife water wildlife. The toxins emitted by certain seaweeds, of this phytoplancton, are transmitted through the trophic chain to man. Sometimes the contamination of these sea fruits provokes empoisoning to the consumers. Sometimes phytoplanctonics efflorescences do not present any significant coloring but can generate an increased liberation of toxins in sea water. The relative concentration of the one here then is detected in the shellfishes. These organisms concentrate the phocotoxines in their hepatopancreas. These are therefore bio potential indicators of the sea environment. We studied, in parallel, the variation of the characteristic abiotics of the Mediterranean sites previously choosen (physico-chimicals parameters and oceanographics parameters) and the variation of the relative toxicity of the bio indicators in every site. It in springs that the zones navies, subjected to important water provisions coming from a river, undergo several excessive floraisons during the spring and the summer, thanks to their continuous supplying in nutriments. We noted that the arrival new water masses. We draw from this that the coastal areas, due to the precipitations of the winter, translates itself at the level of the embouchure of the estuary Oued Laou by the maximum concentration of contained toxins in the shellfishes and that these waters were loaded with drifts of the olive waste, liquid loss abandoned to himself after extraction of the oil of the renowned olives of this region.

  4. Decreasing Fires in Mediterranean Europe

    PubMed Central

    Turco, Marco; Bedia, Joaquín; Di Liberto, Fabrizio; Fiorucci, Paolo; von Hardenberg, Jost; Koutsias, Nikos; Llasat, Maria-Carmen; Xystrakis, Fotios; Provenzale, Antonello

    2016-01-01

    Forest fires are a serious environmental hazard in southern Europe. Quantitative assessment of recent trends in fire statistics is important for assessing the possible shifts induced by climate and other environmental/socioeconomic changes in this area. Here we analyse recent fire trends in Portugal, Spain, southern France, Italy and Greece, building on a homogenized fire database integrating official fire statistics provided by several national/EU agencies. During the period 1985-2011, the total annual burned area (BA) displayed a general decreasing trend, with the exception of Portugal, where a heterogeneous signal was found. Considering all countries globally, we found that BA decreased by about 3020 km2 over the 27-year-long study period (i.e. about -66% of the mean historical value). These results are consistent with those obtained on longer time scales when data were available, also yielding predominantly negative trends in Spain and France (1974-2011) and a mixed trend in Portugal (1980-2011). Similar overall results were found for the annual number of fires (NF), which globally decreased by about 12600 in the study period (about -59%), except for Spain where, excluding the provinces along the Mediterranean coast, an upward trend was found for the longer period. We argue that the negative trends can be explained, at least in part, by an increased effort in fire management and prevention after the big fires of the 1980’s, while positive trends may be related to recent socioeconomic transformations leading to more hazardous landscape configurations, as well as to the observed warming of recent decades. We stress the importance of fire data homogenization prior to analysis, in order to alleviate spurious effects associated with non-stationarities in the data due to temporal variations in fire detection efforts. PMID:26982584

  5. Solar dimming/brightening in the Mediterranean

    NASA Astrophysics Data System (ADS)

    Kambezidis, Harry; Demetriou, Dora; Kaskaoutis, Dimitris; Nastos, Panagiotis

    2010-05-01

    Early analyses of solar radiation records have pointed to a widespread decline of surface solar radiation from the 1950s up to the 1980s in various parts of the world. This phenomenon was attributed to increasing air pollution and has been named "global dimming". More recent analyses with data records updated to near present suggested that surface solar radiation shows no sign of decrease anymore since the 1980s or even started to recover at many locations. This recovery has been named "solar brightening". Air pollution control and the economic breakdown of the former communist countries are the major influential factors for this transition. Further the influence of the recovery from the dimming caused by Mt. Pinatubo volcanic eruption in 1991 and internal climate variability with associated cloud variations were suggested to contribute to the brightening in the 1990s. Despite the interest in the solar dimming/brightening phenomenon the Mediterranean area has not attracted the attention of the scientists in this respect so far. Therefore, the present work tries to fill this gap by providing spatio-temporal analysis of the incoming short-wave solar radiation in the whole area of the Mediterranean Sea in the period 1979-2004 taken from satellites. To give better spatial information about the phenomenon the Mediterranean region has been divided into three sub-regions: the West Mediterranean, from Gibraltar to Corsica, the Central Mediterranean, from Corsica to the Ionian Sea, and the East Mediterranean, from the Ionian Sea to the shores of Syria. The analysis shows that the three sub-regions have not undergone the same spatio-temporal pattern of the phenomenon probably due to the different distribution of aerosols in the region.

  6. Ciguatera-like poisoning in the Mediterranean.

    PubMed

    Raikhlin-Eisenkraft, B; Finkelstein, Y; Spanier, E

    1988-12-01

    A case of group poisoning from the consumption of the fish Sarpa salpa, caught in the Mediterranean coastal waters of Israel, is presented. Mullets and rabbitfish caught at the same site caused no harm. This is the third case of ciguatera poisoning in the region and the first to be transferred by a fish which is not a Red Sea immigrant. It implies that toxic algae dinoflagellates, originating from the Red Sea, crossed the Suez Canal and found their way to the Mediterranean coastal waters.

  7. Global air pollution crossroads over the Mediterranean.

    PubMed

    Lelieveld, J; Berresheim, H; Borrmann, S; Crutzen, P J; Dentener, F J; Fischer, H; Feichter, J; Flatau, P J; Heland, J; Holzinger, R; Korrmann, R; Lawrence, M G; Levin, Z; Markowicz, K M; Mihalopoulos, N; Minikin, A; Ramanathan, V; De Reus, M; Roelofs, G J; Scheeren, H A; Sciare, J; Schlager, H; Schultz, M; Siegmund, P; Steil, B; Stephanou, E G; Stier, P; Traub, M; Warneke, C; Williams, J; Ziereis, H

    2002-10-25

    The Mediterranean Intensive Oxidant Study, performed in the summer of 2001, uncovered air pollution layers from the surface to an altitude of 15 kilometers. In the boundary layer, air pollution standards are exceeded throughout the region, caused by West and East European pollution from the north. Aerosol particles also reduce solar radiation penetration to the surface, which can suppress precipitation. In the middle troposphere, Asian and to a lesser extent North American pollution is transported from the west. Additional Asian pollution from the east, transported from the monsoon in the upper troposphere, crosses the Mediterranean tropopause, which pollutes the lower stratosphere at middle latitudes.

  8. Japanese versus Mediterranean Diets and Cancer.

    PubMed

    Tokudome, Shinkan; Nagaya, Teruo; Okuyama, Harumi; Tokudome, Yuko; Imaeda, Nahomi; Kitagawa, Ikumi; Fujiwara, Nakako; Ikeda, Masato; Goto, Chiho; Ichikawa, Hiromitsu; Kuriki, Kiyonori; Takekuma, Kiyoshi; Shimoda, Asuka; Hirose, Kaoru; Usui, Toshio

    2000-01-01

    Morbidity and mortality statistics, including incidences of fat-related cancers (FRCs), and dietary intake and sources of fats and oils were compared for Japanese, Mediterranean and American people. Incidences of FRCs, except for steeply increasing colon cancer, have remained low in Japan. Similarly, Mediterranean people enjoy relatively low risks of FRCs compared with American people. The low risks of FRCs in Japanese may be explained by limited intake of fats and oils as a whole, and a low ratio of n-6 polyunsaturated fatty acids (PUFAs) versus n-3 PUFAs through consumption of the latter from marine foods. They also frequently consume vegetables and fruit, and dietary fiber. Mediterranean people moderately consume fats and oils from a large amount of olive oil, containing not only oleic acid but also polyphenols (including flavonoids), &mgr;-tocopherol and carotenoids (including &mgr;-carotene), which are antioxidants and anti-carcinogenic as in red wine, vegetables (including herbs) and fruit. The diet also features medium intake of fish and shellfish along with cereals/pasta/bread. From the standpoint of intake of total fat, the low risks of FRCs in Japanese seem "plausible," while the low risks in Mediterranean people may be termed "paradoxical." In summary, limited consumption of fats and oils, moderate intakes of marine foods, and vegetables and fruit, in line with a modest intake of energy may be advocated for promoting health, prolonging life and prevention of lifestyle-related diseases including FRCs. PMID:12718690

  9. Plastic accumulation in the Mediterranean sea.

    PubMed

    Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J Ignacio; Ubeda, Bárbara; Gálvez, José Á; Irigoien, Xabier; Duarte, Carlos M

    2015-01-01

    Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

  10. Morbillivirus and Pilot Whale Deaths, Mediterranean Sea

    PubMed Central

    Esperón, Fernando; Herraéz, Pedro; de los Monteros, Antonio Espinosa; Clavel, Cristina; Bernabé, Antonio; Sánchez-Vizcaino, J. Manuel; Verborgh, Philippe; DeStephanis, Renaud; Toledano, Francisco; Bayón, Alejandro

    2008-01-01

    An outbreak of a lethal morbillivirus infection of long-finned pilot whales occurred in the Mediterranean Sea from the end of October 2006 through April 2007. Sequence analysis of a 426-bp conserved fragment of the morbillivirus phosphoprotein gene indicates that the virus is more closely related to dolphin morbillivirus than to pilot whale morbillivirus. PMID:18439363

  11. Meteotsunami occurrence frequency along the Mediterranean coasts

    NASA Astrophysics Data System (ADS)

    Masina, Marinella; Archetti, Renata; Lamberti, Alberto

    2016-04-01

    A number of research studies describe exceptional destructive meteotsunami events since long time whereas no systematic database is available of moderate events because sea level data were recorded with insufficient resolution. Sea level measurements recently collected with high sampling rate, one per minute or less, by tide gauges positioned along the Mediterranean coasts are examined, aiming to analyze the occurrence of oscillation events in the tsunami frequency range. Sea level data from operating tide stations inside the Mediterranean basin are made publicly available through the Intergovernmental Oceanographic Commission Sea Level Monitoring Facility web site (http://www.ioc-sealevelmonitoring.org/). After the implementation of a rigorous quality check procedure to the raw water level time series, Hilbert transform is applied to two hour high-pass filtered observations to identify tsunami-like oscillation events. Events of seismic origin are identified by consistency between earthquake occurrence and tsunami wave travel time from the earthquake epicenter to the specific tide gauge. Similar analyses are performed to exclude sea waves induced harbor seiches events. A list of probable meteotsunami episodes occurred in the Mediterranean region is so compiled and their occurrence frequency and intensity statistics are evaluated at the different tide gauge sites over the time period of high frequency water level data availability ranging from five to seven years. The effects of atmospheric conditions and seabed topography are discussed. Detection and characterization of meteotsunamis, both of exceptional character and of weak intensity, represent an essential step toward improved assessments of coastal flooding risk along the Mediterranean coasts.

  12. Plastic Accumulation in the Mediterranean Sea

    PubMed Central

    Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J. Ignacio; Ubeda, Bárbara; Gálvez, José Á.; Irigoien, Xabier; Duarte, Carlos M.

    2015-01-01

    Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region. PMID:25831129

  13. Mediterranean dietary pattern and chronic diseases.

    PubMed

    Panico, Salvatore; Mattiello, Amalia; Panico, Camilla; Chiodini, Paolo

    2014-01-01

    The study of the relationship between the Mediterranean way of eating and the occurrence of diseases typical of the economically developed countries has been considered the starting point of nutritional epidemiology. From the Seven Countries Study in the 1950s to the recent European EPIC collaboration, the evaluation of the components of diet-affecting chronic diseases such as cardiovascular disease and cancer has been crucially based on the analysis of foods and nutrients characterizing the Mediterranean dietary habits. This long research history has been marked by a consistency of data over time when either single nutrients/food groups or more complex dietary patterns have been analyzed: The Mediterranean way of eating is a protective tool from cardiovascular diseases and many cancers. Italy has been a natural point of observation, starting from cardiovascular disease in the mid-1950s and continuing with major cancers. In spite of unfavorable lifestyle changes in the Italian population mostly due to globalization of unhealthy habits (richer diet and lower levels of physical activity), those individuals still close to the Mediterranean style are significantly protected. The very recent Italian data derived from the observation of about 50,000 individuals, participating in the Italian cohorts of the EPIC study, confirm these findings and are consistent with results from other European populations and in some cases also from North American populations. Moreover, several dietary trials suggest that such a way of eating improves both the metabolic risk condition for chronic disease and the occurrence of those diseases. In conclusion, a way of eating inspired by a Mediterranean dietary pattern is not only based on evidence but is also a palatable style that has contributed to protection from the epidemic of chronic diseases. PMID:24114475

  14. Mineral dust deposition in Western Mediterranean basin

    NASA Astrophysics Data System (ADS)

    Vincent, Julie; Laurent, Benoit; Bergmatti, Gilles; Losno, Rémi; Bon Nguyen, Elisabeth; Chevaillier, Servanne; Roulet, Pierre; Sauvage, Stéphane; Coddeville, Patrice; Ouboulmane, Noura; Siour, Guillaume; Tovar Sanchez, Antonio; Massanet, Ana; Morales Baquero, Rafael; Di Sarra, Giogio; Sferlazzo, Damiano; Dulac, François; Fornier, Michel; Coursier, Cyril

    2014-05-01

    North African deserts are the world's largest sources of atmospheric mineral dust produced by aeolian erosion. Saharan dust is frequently transported toward Europe over the Mediterranean basin. When deposited in oceanic areas, mineral dust can constitute a key input of nutrients bioavailable for the oceanic biosphere. For instance, Saharan dust deposited in the in the Mediterranean Sea can be a significant source of nutrient like Fe, P and N during summer and autumn. Our objective is to study the deposition Saharan mineral dust in the western Mediterranean basin and to improve how deposition processes are parameterized in 3D regional models. To quantify the deposition flux of Saharan dust in the western Mediterranean region a specific collector (CARAGA) to sample automatically the insoluble atmospheric particle deposition was developed (LISA-ICARE) and a network of CARAGA collectors have been set up. Since 2011, eight CARAGA are then deployed in Frioul, Casset, Montandon and Ersa in France, Mallorca and Granada in Spain, Lampedusa in Italia, and Medenine in Tunisia, along a South-North gradient of almost 2000km from the North African coast to the South of Europe. We observe 10 well identified dust Saharan deposition events at Lampedusa and 6 at Mallorca for a 1-yr sampling period. These dust events are sporadic and the South-North gradient of deposition intensity and frequency is observed (the highest dust mass sampled at the stations are : 2,66 g.m-2 at Lampedusa ; 0,54 g.m-2 at Majorque ; 0,33 g.m-2 at Frioul ; 0,16 g.m-2 at Casset). The ability of the CHIMERE model to reproduce the deposition measurements is tested. The mineral dust plumes simulated over the western Mediterranean basin are also compared to satellite observations (OMI, MODIS) and in-situ measurements performed during the ChArMEx campaign and in the AERONET stations.

  15. Erosion and Land Degradation in Mediterranean areas as a adaptive response to Mediterranean agriiculture

    NASA Astrophysics Data System (ADS)

    Imeson, Anton

    2014-05-01

    The motivation for this session is the statement or claim that Mediterranean areas are sensitive to erosion and desertification. One result of the LEDDRA Approach, which is applying the Complex Adaptive (CAS)paradigm at study sites in Mediterranean Spain, Greece and Italy is that there is just a single socio-environmental system in which land degradation is being caused by the actions of people and the Mediterranean soils have co-eveolved with people under the influence of fire and grazing. They are therefore resilient, and this was demonstrated by Naveh and Thornes. Also the Medalus field sites showed very low rates of erosion. With examples from different Mediterranean landscapes, it is considered that Mediterranean landscapes went through an initial phase of being sensitive to erosion which ended up with the original soils before ploughing or deforestation, being eroded from most of the areas, In some places these are found. LEDDRA The Leddra approach is to consider different states which are separated by transitions. The first state is that of the deforestaion and destruction of the forest that took place 6000 10000 years ago, in the Eastern and Northern Mediterranean, and 2000 to 4,000 years ago in large areas of the Western Mediterranean, and 100 to 400 years ago in California. Australia, New Zealand and Chile. The second state involves appropriating and settling the land from indigenous people and introducing cattle and sheep and Mediterranean crops. The current state of desertification is one in which erosion occurs because of the use of specific cultivation methods and subsidies for irrigating and producing crops outside of their range. In the Mediterranean landscape State, such as found near Santiago in Chile and in Crete, society gains many cultural benefits from grazing. However, the consequences of this are that the whole ecosystem is maintained in an arid state, so that areas in Crete receiving 800-1100 mm rainfall have a semi arid vegetation, instead

  16. Hydrometeorological extremes in the Mediterranean area

    NASA Astrophysics Data System (ADS)

    Llasat, M. C.; Rigo, T.

    2003-04-01

    Between the 9th and 18th of November of 2001, a succession of hydrometeorological hazards affected the West of the Mediterranean area. High rainfalls above 200mm /24 h gave place to catastrophic floods in Algeria, Balearic Islands, Morocco and the Northeast of the Iberian Peninsula; extreme winds of more than 30 m/s of sustained speed uprooted thousands of trees, removed up to 50 per cent of the sand in a great number of beaches of the Balearic Islands and Catalonia and made waves over 11 m high; combined with the wind, the hail destroyed the crops in the littoral region of Catalonia, whereas a cold wave affected the rest of Spain, with the snow arriving to Catalonia. Over 600 people died in Algeria and up to 10 in Spain, with material damage up to 150M euros. In this case a strong cyclone was identified as one of the main causes of the severe weather produced. A study developed into the framework of the MEDEX project shows that the Gulf of Genoa (mainly medium and deep cyclones) and the Iberian Peninsula (mainly shallow cyclones) are the most cyclogenesis prone areas in the West Mediterranean (Campins et al, 2002). Although the West part of the Mediterranean shows the maximum number of cyclones, it is also important in the Eastern part (smoothed values are, respectively, 437 and 353, following the results of Gil et al, 2002). Although the events of November 2001 are not usual in the Mediterranean area, hydrometeorological hazards that affect more than one country (usually Spain, France and Italy) are frequent. But not all the catastrophic events are so vast. On the 25th of September of 1962 a catastrophic flash-flood produced 815 casualties in less than 150 km2 and on the 10th of June of 2000, more than 200 mm were recorded in less than 3 hours. Although the Mediterranean climate is identified with dry summers, that season shows the greatest rate of convective events (Llasat, 2001) that can lead to flash floods in little catchments, usually in mountain and coastal

  17. Early Spring Dust over the Mediterranean Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) observed this large cloud of dust (brownish pixels) blowing from northern Africa across the Mediterranean Sea on March 4, 2002. The dust can be seen clearly blowing across Southern Italy, Albania, Greece, and Turkey-all along the Mediterranean's northeastern shoreline. Notice that there also appears to be human-made aerosol pollution (greyish pixels) pooling in the air just south of the Italian Alps and blowing southeastward over the Adriatic Sea. The Alps can be easily identified as the crescent-shaped, snow-capped mountain range in the top center of this true-color scene. There also appears to be a similar haze over Austria, Hungary, and Yugoslavia to the north and east of Italy. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  18. Storms of Mediterranean and Atlantic legends

    NASA Astrophysics Data System (ADS)

    Schoenenwald, N.; Tabeaud, M.

    2009-09-01

    Weather extremes and notably wind storms are very often the channel ones since they are suspected of being the outward signs of climate change. However, even if audiovisual medias talk about wind storms in a very similar way, tales and legends stories account for the richness of their representations. Coastal and insular regions, whatever Atlantic or Mediterranean, are the ones where wind storms are most mentioned. The comparison between the tales and legends of these two regions, with distinct climatic characteristics, allows to underline the similarities and dissimilarities about the impregnation (or impact) of wind storms on these territories. Winds and storms distinguish spaces through vocabulary which can be peculiar to a region. Nevertheless, they also bring them together because above the local cultures is the human thought upon which wind storms create comparable perceptions, whatever the region. Key words: wind storms, Mediterranean regions, Atlantic regions, perceptions, representations.

  19. Food Processing and the Mediterranean Diet

    PubMed Central

    Hoffman, Richard; Gerber, Mariette

    2015-01-01

    The benefits of the Mediterranean diet (MD) for protecting against chronic disorders such as cardiovascular disease are usually attributed to high consumption of certain food groups such as vegetables, and low consumption of other food groups such as meat. The influence of food processing techniques such as food preparation and cooking on the nutrient composition and nutritional value of these foods is not generally taken into consideration. In this narrative review, we consider the mechanistic and epidemiological evidence that food processing influences phytochemicals in selected food groups in the MD (olives, olive oil, vegetables and nuts), and that this influences the protective effects of these foods against chronic diseases associated with inflammation. We also examine how the pro-inflammatory properties of meat consumption can be modified by Mediterranean cuisine. We conclude by discussing whether food processing should be given greater consideration, both when recommending a MD to the consumer and when evaluating its health properties. PMID:26393643

  20. Anthropogenic enhancement of Egypt's Mediterranean fishery

    PubMed Central

    Oczkowski, Autumn J.; Nixon, Scott W.; Granger, Stephen L.; El-Sayed, Abdel-Fattah M.; McKinney, Richard A.

    2009-01-01

    The highly productive coastal Mediterranean fishery off the Nile River delta collapsed after the completion of the Aswan High Dam in 1965. But the fishery has been recovering dramatically since the mid-1980s, coincident with large increases in fertilizer application and sewage discharge in Egypt. We use stable isotopes of nitrogen (δ15N) to demonstrate that 60%–100% of the current fishery production may be from primary production stimulated by nutrients from fertilizer and sewage runoff. Although the establishment of the dam put Egypt in an ideal position to observe the impact of rapid increases in nutrient loading on coastal productivity in an extremely oligotrophic sea, the Egyptian situation is not unique. Such anthropogenically enhanced fisheries also may occur along the northern rim of the Mediterranean and offshore of some rapidly developing tropical countries, where nutrient concentrations in the coastal waters were previously very low. PMID:19164510

  1. Strategic exposure. Proliferation around the Mediterranean

    SciTech Connect

    Lesser, I.O.; Tellis, A.J.

    1996-12-31

    A leading post-Cold War security interest of U.S. policymakers and strategists is the proliferation of nuclear, chemical, and biological weapons of mass destruction (WMDs) and the means for their delivery at ever longer ranges. For the military services, including the U.S. Army, proliferation trends and their regional effects are matters of great operational and strategic significance, with serious implications for U.S. freedom of action in future crises. Nowhere is the prospect of the spread of WMDs likely to have a more pronounced effect on strategic perceptions than around the Mediterranean. We analyzed proliferation trends and regional security consequences in the Mediterranean region and reached the following conclusions.

  2. Food Processing and the Mediterranean Diet.

    PubMed

    Hoffman, Richard; Gerber, Mariette

    2015-09-17

    The benefits of the Mediterranean diet (MD) for protecting against chronic disorders such as cardiovascular disease are usually attributed to high consumption of certain food groups such as vegetables, and low consumption of other food groups such as meat. The influence of food processing techniques such as food preparation and cooking on the nutrient composition and nutritional value of these foods is not generally taken into consideration. In this narrative review, we consider the mechanistic and epidemiological evidence that food processing influences phytochemicals in selected food groups in the MD (olives, olive oil, vegetables and nuts), and that this influences the protective effects of these foods against chronic diseases associated with inflammation. We also examine how the pro-inflammatory properties of meat consumption can be modified by Mediterranean cuisine. We conclude by discussing whether food processing should be given greater consideration, both when recommending a MD to the consumer and when evaluating its health properties.

  3. Sediment transport in two mediterranean regulated rivers.

    PubMed

    Lobera, G; Batalla, R J; Vericat, D; López-Tarazón, J A; Tena, A

    2016-01-01

    Mediterranean climate is characterized by highly irregular rainfall patterns with marked differences between wet and dry seasons which lead to highly variable hydrological fluvial regimes. As a result, and in order to ensure water availability and reduce its temporal variability, a high number of large dams were built during the 20th century (more than 3500 located in Mediterranean rivers). Dams modify the flow regime but also interrupt the continuity of sediment transfer along the river network, thereby changing its functioning as an ecosystem. Within this context, the present paper aims to assess the suspended sediment loads and dynamics of two climatically contrasting Mediterranean regulated rivers (i.e. the Ésera and Siurana) during a 2-yr period. Key findings indicate that floods were responsible for 92% of the total suspended sediment load in the River Siurana, while this percentage falls to 70% for the Ésera, indicating the importance of baseflows on sediment transport in this river. This fact is related to the high sediment availability, with the Ésera acting as a non-supply-limited catchment due to the high productivity of the sources (i.e. badlands). In contrast, the Siurana can be considered a supply-limited system due to its low geomorphic activity and reduced sediment availability, with suspended sediment concentration remaining low even for high magnitude flood events. Reservoirs in both rivers reduce sediment load up to 90%, although total runoff is only reduced in the case of the River Ésera. A remarkable fact is the change of the hydrological character of the River Ésera downstream for the dam, shifting from a humid mountainous river regime to a quasi-invariable pattern, whereas the Siurana experiences the opposite effect, changing from a flashy Mediterranean river to a more constant flow regime below the dam.

  4. "Towards an even healthier Mediterranean diet".

    PubMed

    Estruch, R; Salas-Salvadó, J

    2013-12-01

    Dietary guidelines to promote good health are usually based on foods, nutrients, and dietary patterns predictive of chronic disease risk in epidemiologic studies. However, sound nutritional recommendations for cardiovascular prevention should be based on the results of large randomized clinical trials with "hard" end-points as the main outcome. Such evidence has been obtained for the Mediterranean diet from the PREDIMED (Prevención con Dieta Mediterránea) trial and the Lyon Heart Study. The traditional Mediterranean diet was that found in olive growing areas of Crete, Greece, and Southern Italy in the late 1950s. Their major characteristics include: a) a high consumption of cereals, legumes, nuts, vegetables, and fruits; b) a relatively high-fat consumption, mostly provided by olive oil; c) moderate to high fish consumption; d) poultry and dairy products consumed in moderate to small amounts; e) low consumption of red meats, and meat products; and f) moderate alcohol intake, usually in the form of red wine. However, these protective effects of the traditional Mediterranean diet may be even greater if we upgrade the health effects of this dietary pattern changing the common olive oil used for extra-virgin olive oil, increasing the consumption of nuts, fatty fish and whole grain cereals, reducing sodium intake, and maintaining a moderate consumption of wine with meals. PMID:24263037

  5. Mediterranean Diet and Risk of Dementia.

    PubMed

    Safouris, Apostolos; Tsivgoulis, Georgios; Sergentanis, Theodoros N; Psaltopoulou, Theodora

    2015-01-01

    Dementia is a major global health challenge, as its burden on society will increase with population aging. Given the lack of effective pharmaceutical treatment for common types of dementia including Alzheimer's disease and vascular dementia, research interest in lifestyle modifications that could prevent, postpone the clinical syndrome or decelerate progression of dementia is growing. Among the various dietary patterns that were tested for their effects on cognition, the traditional Mediterranean diet (MeDi) has shown promising results. This review aims to summarize the epidemiological evidence on the effects of MeDi on the prevention of dementia, presenting data from cross-sectional as well as longitudinal observational studies conducted both in Mediterranean and non-Mediterranean countries. These findings have been also reproduced in the context of one recent randomized-controlled clinical trial. Postulated mechanisms of action that may account for the potential protective effect of MeDi on cognitive impairment will be briefly discussed. Despite the fact that the link between MeDi and cognitive decline has been only explored for less than a decade, data on efficacy is rapidly increasing and allows optimism that MeDi could emerge as an alternative prophylactic treatment for dementia.

  6. Patient with Recurrent Polyserositis (Familial Mediterranean Fever).

    PubMed

    Agarwal, Arun; Sharma, Samiksha

    2015-08-01

    Familial Mediterranean fever (FMF) is a hereditary autosomal recessive ,systemic, auto-inflammatory disorder characterized by sporadic, unpredictable attacks of fever and serosal inflammation. FMF is caused by mutations in MEFV, a gene located on the short arm of chromosome 16 (16p13) which encodes a protein 'Pyrin'. The disorder has been given various names including familial paroxysmal polyserositis, periodic peritonitis, recurrent polyserositis, benign paroxysmal peritonitis, and periodic disease or periodic fever, As the name indicates, FMF occurs within families and is much more common in individuals of Mediterranean descent than in persons of any other ethnicity. It has been described in several ethnic groups including Sephardic Jews, Armenians, Turks, North Africans, Arabs, Greeks, and Italians. However, the disease is not restricted to these groups and sporadic cases have been reported. Diagnosis is usually clinical and it classically presents with unprovoked, recurrent attacks of fever and painful polyserositis mainly affecting the peritoneum (most common), synovium, and pleura that usually (but not always) begin in childhood. We present a atypical case of FMF with type 1 Diabetes Mellitus and FMF who had no fever, Mediterranean ancestory or family history and discuss his clinical features,diagnosis and management. PMID:27604438

  7. Bioethics in Mediterranean culture: the Spanish experience.

    PubMed

    Busquets, Ester; Roman, Begoña; Terribas, Núria

    2012-11-01

    This article presents a view of bioethics in the Spanish context. We may identify several features common to Mediterranean countries because of their relatively similar social organisation. Each country has its own distinguishing features but we would point two aspects which are of particular interest: the Mediterranean view of autonomy and the importance of Catholicism in Mediterranean culture. The Spanish experience on bioethics field has been marked by these elements, trying to build a civic ethics alternative, with the law as an important support. So, Spanish bioethics has been developed in two parallel levels: in the academic and policy maker field (University and Parliament) and in clinical practice (hospitals and healthcare ethics committees), with different paces and methods. One of the most important changes in the paternalistic mentality has been promoted through the recognition by law of the patient's rights and also through the new generation of citizens, clearly aware on the exercise of autonomy. Now, the healthcare professionals have a new challenge: adapt their practice to this new paradigm.

  8. Miocene to Pliocene osmium isotopic records of Mediterranean sediments

    NASA Astrophysics Data System (ADS)

    Kuroda, Junichiro; Jiménez-Espejo, Francisco J.; Nozaki, Tatsuo; Gennari, Rocco; Lugli, Stefano; Manzi, Vinicio; Roveri, Marco; Flecker, Rachel; Suzuki, Katsuhiko; Yoshimura, Toshihiro; Sierro, Francisco; Ohkouchi, Naohiko

    2015-04-01

    In the late Miocene the Mediterranean Sea experienced a salinity crisis and thick sequences of evaporites precipitated across the basin. In this study we report Os isotopic records from drilled cores in the Mediterranean; the Balearic Sea, the Tyrrhenian Sea, the Ionian Basin and the Florence Rise. Pliocene sediments at all sites show 187Os/188Os values close to that of the coeval ocean water, indicating that the Mediterranean was connected to the North Atlantic. Evaporitic sediments deposited during the late Miocene however, have 187Os/188Os values lower than coeval ocean water values and samples from the eastern Mediterranean and Ionian basins are particularly low. Os isotopic ratios of the pre-evaporite sediments in the western Mediterranean are almost identical to that of the coeval ocean water. In contrast, equivalent sediments from the Florence Rise have significantly lower 187Os/188Os values. The offset of Mediterranean evaporite 187Os/188Os is attributed to limited exchange with the North Atlantic during the Messinian Salinity Crisis (MSC). The source of unradiogenic Os is likely to be weathering of ultramafic rocks (ophiolites) cropping out in the Mediterranean's drainage basins. The offset in the Os ratio on the Florence Rise is attributed either to limited water exchange between eastern and western Mediterranean, or to local effects associated with exhumation of ophiolites around the eastern Mediterranean Sea.

  9. Droughts and forest fires in Mediterranean Europe

    NASA Astrophysics Data System (ADS)

    Turco, Marco; Llasat, Maria-Carmen; von Hardenberg, Jost; Provenzale, Antonello

    2015-04-01

    Most of the total burned area in Europe occurs in Mediterranean regions, with severe economic and environmental damage, life loss and an average of about 4500 km2 burned every year. A better understanding of the impacts on wildfires of environmental and socioeconomic changes is crucial to develop adequate measures of prevention, adaptation and mitigation in this area. Here we focus on the impact of droughts on fires in European Mediterranean regions (Portugal, Spain, the south of France, Italy, Greece). This goal will be achieved through three specific supporting objectives: (1) Understanding past changes in fires in this region (extending the study of [1]); (2) Comparing and analyzing different drought indices (e.g. SPI, SPEI and SSI; see [2, 3] for more details on those indices); (3) Modeling the interaction between drought and fires (following and extending the study of [4]). We develop relatively simple regression models that link the fire activity to the key climate drivers. These models could be used to estimate fire responses to different climate change projections and environmental and socioeconomic scenarios ([5]). *References [1] Turco M., Llasat M. C., Tudela A., Castro X., and Provenzale A. Brief communication Decreasing fires in a Mediterranean region (1970-2010, NE Spain). Natural Hazards and Earth System Science, 13(3):649-652, 2013. [2] Zengchao H., AghaKouchak A., Nakhjiri N., and Farahmand A. Global Integrated Drought Monitoring and Prediction System. Scientific Data, 1:1-10, 2014. [3] Vicente-Serrano, S. M., Beguería, S. and López-Moreno, J. I. A multiscalar drought index sensitive to global warming: The standardized precipitation evapotranspiration index. Journal of Climate, 23:1696-1718, 2010. [4] Turco M., Llasat M. C., von Hardenberg J., and Provenzale A. Impact of climate variability on summer fires in a Mediterranean environment (northeastern Iberian Peninsula). Climatic Change, 116:665-678, 2013. [5] Turco M., Llasat M. C., von

  10. Adaptive Radiation in Mediterranean Cistus (Cistaceae)

    PubMed Central

    Guzmán, Beatriz; Lledó, María Dolores; Vargas, Pablo

    2009-01-01

    Background Adaptive radiation in Mediterranean plants is poorly understood. The white-flowered Cistus lineage consists of 12 species primarily distributed in Mediterranean habitats and is herein subject to analysis. Methodology/Principal Findings We conducted a “total evidence” analysis combining nuclear (ncpGS, ITS) and plastid (trnL-trnF, trnK-matK, trnS-trnG, rbcL) DNA sequences and using MP and BI to test the hypothesis of radiation as suggested by previous phylogenetic results. One of the five well-supported lineages of the Cistus-Halimium complex, the white-flowered Cistus lineage, comprises the higher number of species (12) and is monophyletic. Molecular dating estimates a Mid Pleistocene (1.04±0.25 Ma) diversification of the white-flowered lineage into two groups (C. clusii and C. salviifolius lineages), which display asymmetric characteristics: number of species (2 vs. 10), leaf morphologies (linear vs. linear to ovate), floral characteristics (small, three-sepalled vs. small to large, three- or five-sepalled flowers) and ecological attributes (low-land vs. low-land to mountain environments). A positive phenotype-environment correlation has been detected by historical reconstructions of morphological traits (leaf shape, leaf labdanum content and leaf pubescence). Ecological evidence indicates that modifications of leaf shape and size, coupled with differences in labdanum secretion and pubescence density, appear to be related to success of new species in different Mediterranean habitats. Conclusions/Significance The observation that radiation in the Cistus salviifolius lineage has been accompanied by the emergence of divergent leaf traits (such as shape, pubescence and labdanum secretion) in different environments suggets that radiation in the group has been adaptive. Here we argued that the diverse ecological conditions of Mediterranean habitats played a key role in directing the evolution of alternative leaf strategies in this plant group. Key

  11. Estimation of Atlantic-Mediterranean netflow variability

    NASA Astrophysics Data System (ADS)

    Guerreiro, Catarina; Peliz, Alvaro; Miranda, Pedro

    2016-04-01

    The exchanges at the Strait of Gibraltar are extremely difficult to measure due to the strong temporal and across-strait variabilities; yet the Atlantic inflow into the Mediterranean is extremely important both for climate and to ecosystems. Most of the published numerical modeling studies do not resolve the Strait of Gibraltar realistically. Models that represent the strait at high resolution focus primarily in high frequency dynamics, whereas long-term dynamics are studied in low resolution model studies, and for that reason the Strait dynamics are poorly resolved. Estimating the variability of the exchanges requires long term and high-resolutions studies, thus an improved simulation with explicit and realistic representation of the Strait is necessary. On seasonal to inter-annual timescales the flow is essentially driven by the net evaporation contribution and consequently realistic fields of precipitation and evaporation are necessary for model setup. A comparison between observations, reanalysis and combined products shows ERA-Interim Reanalysis has the most suitable product for Mediterranean Sea. Its time and space variability are in close agreement with NOC 1.1 for the common period (1980 - 1993) and also with evaporation from OAFLUX (1989 - 2014). Subinertial fluctuations, periods from days to a few months, are the second most energetic, after tides, and are the response to atmospheric pressure fluctuations and local winds. Atmospheric pressure fluctuations in the Mediterranean cause sea level oscillations that induce a barotropic flow through the Strait. Candela's analytical model has been used to quantify this response in later studies, though comparison with observations points to an underestimation of the flow at strait. An improved representation of this term contribution to the Atlantic - Mediterranean exchange must be achieved on longer time-scales. We propose a new simulation for the last 36 years (1979 - 2014) for the Mediterranean - Atlantic

  12. Relationships between deep-sea tunicate populations west and east of the Straits of Gibraltar

    NASA Astrophysics Data System (ADS)

    Monniot, Claude; Monniot, Françoise

    Twenty-four species of tunicates were collected from deep bottoms on each side of the Gibraltar sill, in the adjacent Mediterranean Sea and Atlantic Ocean. In the Atlantic, stations bathed by Atlantic and Mediterranean waters were both sampled. No transport of ascidian taxa by the outflow of Mediterranean water into the Atlantic is apparent. The alternative hypothesis of an Atlantic origin of bathyal ascidian species in the Mediterranean Sea is proposed.

  13. Eutrophication and environmental policy in the Mediterranean Sea: a review.

    PubMed

    Karydis, Michael; Kitsiou, Dimitra

    2012-08-01

    The Mediterranean Sea is a semienclosed basin connected with the open sea mainly through the Strait of Gibraltar. Due to the circulation pattern and the long residence time ranging between 80 and 100 years, the Mediterranean Sea is a sensitive environment to eutrophication pressures. The main body of water of the Mediterranean is characterized by very low nutrient concentrations, and therefore, the Mediterranean is classified among the most oligotrophic (very poor waters in nutrients) seas of the world's oceans. However, some coastal areas, mainly in the northern part of the basin, receive excessive loads of nutrients from sewage effluents, river fluxes, aquaculture farms, fertilizers, and industrial facilities, showing intense eutrophic phenomena with many adverse effects for the marine ecosystem and humans. Various national and international authorities, in addition to monitoring, have taken legal and administrative measures to mitigate eutrophication trends in the area. The Mediterranean environment is a good paradigm of integration of extensive legal framework, scientific knowledge, and administrative practices. The Barcelona Convention, the Mediterranean Action Plan, and European Union Directives on water quality and coastal management, together with scientific information derived from international research programs in the Mediterranean, provide a sound background for practical actions in eutrophication problems. In the present work, the problem of coastal eutrophication in the Mediterranean is reviewed in connection with public policies of the Mediterranean States based on national and international legislation and scientific knowledge on Mediterranean oceanography-ecology and actions coordinated by international bodies. These common actions and practices on coastal management are also discussed in relation to the need for sustainable development and protection of the coastal zone in the Mediterranean Sea. PMID:21956336

  14. Eutrophication and environmental policy in the Mediterranean Sea: a review.

    PubMed

    Karydis, Michael; Kitsiou, Dimitra

    2012-08-01

    The Mediterranean Sea is a semienclosed basin connected with the open sea mainly through the Strait of Gibraltar. Due to the circulation pattern and the long residence time ranging between 80 and 100 years, the Mediterranean Sea is a sensitive environment to eutrophication pressures. The main body of water of the Mediterranean is characterized by very low nutrient concentrations, and therefore, the Mediterranean is classified among the most oligotrophic (very poor waters in nutrients) seas of the world's oceans. However, some coastal areas, mainly in the northern part of the basin, receive excessive loads of nutrients from sewage effluents, river fluxes, aquaculture farms, fertilizers, and industrial facilities, showing intense eutrophic phenomena with many adverse effects for the marine ecosystem and humans. Various national and international authorities, in addition to monitoring, have taken legal and administrative measures to mitigate eutrophication trends in the area. The Mediterranean environment is a good paradigm of integration of extensive legal framework, scientific knowledge, and administrative practices. The Barcelona Convention, the Mediterranean Action Plan, and European Union Directives on water quality and coastal management, together with scientific information derived from international research programs in the Mediterranean, provide a sound background for practical actions in eutrophication problems. In the present work, the problem of coastal eutrophication in the Mediterranean is reviewed in connection with public policies of the Mediterranean States based on national and international legislation and scientific knowledge on Mediterranean oceanography-ecology and actions coordinated by international bodies. These common actions and practices on coastal management are also discussed in relation to the need for sustainable development and protection of the coastal zone in the Mediterranean Sea.

  15. Measuring Implicit European and Mediterranean Landscape Identity: A Tool Proposal.

    PubMed

    Fornara, Ferdinando; Dentale, Francesco; Troffa, Renato; Piras, Simona

    2016-01-01

    This study presents a tool - the Landscape Identity Implicit Association Test (LI-IAT) - devoted to measure the implicit identification with European and Mediterranean landscapes. To this aim, a series of prototypical landscapes was selected as stimulus, following an accurate multi-step procedure. Participants (N = 174), recruited in two Italian cities, performed two LI-IATs devoted to assess their identification with European vs. Not-European and Mediterranean vs. Not-Mediterranean prototypical landscapes. Psychometric properties and criterion validity of these measures were investigated. Two self-report measures, assessing, respectively, European and Mediterranean place identity and pleasantness of the target landscapes, were also administered. Results showed: (1) an adequate level of internal consistency for both LI-IATs; (2) a higher identification with European and Mediterranean landscapes than, respectively, with Not-European and Not-Mediterranean ones; and (3) a significant positive relationship between the European and Mediterranean LI-IATs and the corresponding place identity scores, also when pleasantness of landscapes was controlled for. Overall, these findings provide a first evidence supporting the reliability and criterion validity of the European and Mediterranean LI-IATs.

  16. Measuring Implicit European and Mediterranean Landscape Identity: A Tool Proposal

    PubMed Central

    Fornara, Ferdinando; Dentale, Francesco; Troffa, Renato; Piras, Simona

    2016-01-01

    This study presents a tool – the Landscape Identity Implicit Association Test (LI-IAT) – devoted to measure the implicit identification with European and Mediterranean landscapes. To this aim, a series of prototypical landscapes was selected as stimulus, following an accurate multi-step procedure. Participants (N = 174), recruited in two Italian cities, performed two LI-IATs devoted to assess their identification with European vs. Not-European and Mediterranean vs. Not-Mediterranean prototypical landscapes. Psychometric properties and criterion validity of these measures were investigated. Two self-report measures, assessing, respectively, European and Mediterranean place identity and pleasantness of the target landscapes, were also administered. Results showed: (1) an adequate level of internal consistency for both LI-IATs; (2) a higher identification with European and Mediterranean landscapes than, respectively, with Not-European and Not-Mediterranean ones; and (3) a significant positive relationship between the European and Mediterranean LI-IATs and the corresponding place identity scores, also when pleasantness of landscapes was controlled for. Overall, these findings provide a first evidence supporting the reliability and criterion validity of the European and Mediterranean LI-IATs. PMID:27642284

  17. Measuring Implicit European and Mediterranean Landscape Identity: A Tool Proposal

    PubMed Central

    Fornara, Ferdinando; Dentale, Francesco; Troffa, Renato; Piras, Simona

    2016-01-01

    This study presents a tool – the Landscape Identity Implicit Association Test (LI-IAT) – devoted to measure the implicit identification with European and Mediterranean landscapes. To this aim, a series of prototypical landscapes was selected as stimulus, following an accurate multi-step procedure. Participants (N = 174), recruited in two Italian cities, performed two LI-IATs devoted to assess their identification with European vs. Not-European and Mediterranean vs. Not-Mediterranean prototypical landscapes. Psychometric properties and criterion validity of these measures were investigated. Two self-report measures, assessing, respectively, European and Mediterranean place identity and pleasantness of the target landscapes, were also administered. Results showed: (1) an adequate level of internal consistency for both LI-IATs; (2) a higher identification with European and Mediterranean landscapes than, respectively, with Not-European and Not-Mediterranean ones; and (3) a significant positive relationship between the European and Mediterranean LI-IATs and the corresponding place identity scores, also when pleasantness of landscapes was controlled for. Overall, these findings provide a first evidence supporting the reliability and criterion validity of the European and Mediterranean LI-IATs.

  18. Measuring Implicit European and Mediterranean Landscape Identity: A Tool Proposal.

    PubMed

    Fornara, Ferdinando; Dentale, Francesco; Troffa, Renato; Piras, Simona

    2016-01-01

    This study presents a tool - the Landscape Identity Implicit Association Test (LI-IAT) - devoted to measure the implicit identification with European and Mediterranean landscapes. To this aim, a series of prototypical landscapes was selected as stimulus, following an accurate multi-step procedure. Participants (N = 174), recruited in two Italian cities, performed two LI-IATs devoted to assess their identification with European vs. Not-European and Mediterranean vs. Not-Mediterranean prototypical landscapes. Psychometric properties and criterion validity of these measures were investigated. Two self-report measures, assessing, respectively, European and Mediterranean place identity and pleasantness of the target landscapes, were also administered. Results showed: (1) an adequate level of internal consistency for both LI-IATs; (2) a higher identification with European and Mediterranean landscapes than, respectively, with Not-European and Not-Mediterranean ones; and (3) a significant positive relationship between the European and Mediterranean LI-IATs and the corresponding place identity scores, also when pleasantness of landscapes was controlled for. Overall, these findings provide a first evidence supporting the reliability and criterion validity of the European and Mediterranean LI-IATs. PMID:27642284

  19. INTRODUCTION: DESERTIFICATION AND SECURITY - PERSPECTIVES FOR THE MEDITERRANEAN REGION

    EPA Science Inventory

    This book focuses on two basic concepts: security and desertification in the Mediterranean Region and their linkages. It emerged from a single meeting of the "Workshop on Desertification in the Mediterranean Region. A Security Issue" held in Valencia, Spain on 2-5 December 2003...

  20. Mediterranean Diet and cancer risk: an open issue.

    PubMed

    D'Alessandro, Annunziata; De Pergola, Giovanni; Silvestris, Franco

    2016-09-01

    The traditional Mediterranean Diet of the early 1960s meets the characteristics of an anticancer diet defined by the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AIRC). A diet rich of whole grains, pulses, vegetables and fruits, limited in high-calorie foods (foods high in sugar or fat), red meat and foods high in salt, without sugary drinks and processed meat is recommended by the WCRF/AIRC experts to reduce the risk of cancer. The aim of this review was to examine whether Mediterranean Diet is protective or not against cancer risk. Three meta-analyses of cohort studies reported that a high adherence to the Mediterranean Diet significantly reduces the risk of cancer incidence and/or mortality. Nevertheless, the Mediterranean dietary pattern defined in the studies' part of the meta-analyses has qualitative and/or quantitative differences compared to the Mediterranean Diet of the early 1960s. Therefore, the protective role of the Mediterranean Diet against cancer has not definitely been established. In epidemiological studies, a universal definition of the Mediterranean Diet, possibly the traditional Mediterranean Diet of the early 1960s, could be useful to understand the role of this dietary pattern in cancer prevention. PMID:27251477

  1. Mediterranean Diet and cancer risk: an open issue.

    PubMed

    D'Alessandro, Annunziata; De Pergola, Giovanni; Silvestris, Franco

    2016-09-01

    The traditional Mediterranean Diet of the early 1960s meets the characteristics of an anticancer diet defined by the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AIRC). A diet rich of whole grains, pulses, vegetables and fruits, limited in high-calorie foods (foods high in sugar or fat), red meat and foods high in salt, without sugary drinks and processed meat is recommended by the WCRF/AIRC experts to reduce the risk of cancer. The aim of this review was to examine whether Mediterranean Diet is protective or not against cancer risk. Three meta-analyses of cohort studies reported that a high adherence to the Mediterranean Diet significantly reduces the risk of cancer incidence and/or mortality. Nevertheless, the Mediterranean dietary pattern defined in the studies' part of the meta-analyses has qualitative and/or quantitative differences compared to the Mediterranean Diet of the early 1960s. Therefore, the protective role of the Mediterranean Diet against cancer has not definitely been established. In epidemiological studies, a universal definition of the Mediterranean Diet, possibly the traditional Mediterranean Diet of the early 1960s, could be useful to understand the role of this dietary pattern in cancer prevention.

  2. The multidecadal component of the Mediterranean summer variability

    NASA Astrophysics Data System (ADS)

    OrtizBevia, M. J.; RuizdeElvira, A.; Alvarez-Garcia, F. J.; Tasambay-Salazar, M.

    2016-09-01

    This study targets the low frequency components of the anomalous Mediterranean summer climatic variability. This last is characterised here by two indexes obtained from a statistical analysis of Mediterranean sea surface temperature anomalies. The evolution of the first of them, the Western Mediterranean Index, is dominated by a multidecadal timescale. This Index has a strong statistical impact on the summer air temperature anomalies in the European region. In the other index, the Mediterranean Dipole Index, the decadal timescale plays a major part. This last Index is linked to anomalous summer precipitations in some central European regions. A statistical methodology is used in order to identify some feedback relationships between the two Mediterranean indexes and other climate indexes which characterise some global or regional variability. In the case of the Western Mediterranean Index, the analysis reveals significant feedback relationships with two of these indexes. The selected predictors are introduced as variables in a statistical feedback model. The cross-skills scored in a cross-validation hindcast experiment reveals an important potential predictability. In this way, the multidecadal Mediterranean summer sea surface temperature variability appears as the result of two forcings, one related to the north-western Atlantic processes and the other connected to the north tropical Atlantic, and to a weak feedback onto the Atlantic. In the case of the Mediterranean Dipole Mode Index we have not found enough predictive potential in the feedback relationships identified.

  3. Mediterranean diet in predementia and dementia syndromes.

    PubMed

    Solfrizzi, V; Frisardi, V; Seripa, D; Logroscino, G; Imbimbo, B P; D'Onofrio, G; Addante, F; Sancarlo, D; Cascavilla, L; Pilotto, A; Panza, F

    2011-08-01

    There is a critical need to potentially individualize new strategies able to prevent and to slow down the progression of predementia and dementia syndromes. Only recently higher adherence to a Mediterranean-type diet was associated with decreased cognitive decline although the Mediterranean diet (MeDi) combines several foods, micro- and macronutrients already separately proposed as potential protective factors against dementia and predementia syndromes. In fact, elevated saturated fatty acids could have negative effects on age-related cognitive decline and mild cognitive impairment (MCI). Furthermore, at present, epidemiological evidence suggested a possible association among fish consumption, monounsaturated fatty acids and polyunsaturated fatty acids (PUFA) (particularly, n-3 PUFA) and reduced risk of cognitive decline and dementia. Light to moderate alcohol use may be associated with a reduced risk of incident dementia and Alzheimer's disease (AD), while for vascular dementia, cognitive decline, and predementia syndromes the current evidence is only suggestive of a protective effect. Finally, the limited epidemiological evidence available on fruit and vegetable consumption and cognition generally supported a protective role of these macronutrients against cognitive decline, dementia, and AD. Moreover, recent prospective studies provided evidence that higher adherence to a Mediterranean-type diet could be associated with slower cognitive decline, reduced risk of progression from MCI to AD, reduced risk of AD, and decreased all-causes mortality in AD patients. These findings suggested that adherence to the MeDi may affect not only the risk for AD, but also for predementia syndromes and their progression to overt dementia. Nonetheless, at present, no definitive dietary recommendations are possible. However, high levels of consumption of fats from fish, vegetable oils, non-starchy vegetables, low glycemic fruits, and diet low in foods with added sugars and with

  4. Proposal of a Mediterranean Diet Serving Score

    PubMed Central

    Monteagudo, Celia; Mariscal-Arcas, Miguel; Rivas, Ana; Lorenzo-Tovar, María Luisa; Tur, Josep A.; Olea-Serrano, Fátima

    2015-01-01

    Background and Aims Numerous studies have demonstrated a relationship between Mediterranean Diet (MD) adherence and the prevention of cardiovascular diseases, cancer, and diabetes, etc. The study aim was to validate a novel instrument to measure MD adherence based on the consumption of food servings and food groups, and apply it in a female population from southern Spain and determining influential factors. Methods and Results The study included 1,155 women aged 12-83 yrs, classified as adolescents, adults, and over-60-yr-olds. All completed a validated semi-quantitative food frequency questionnaire (FFQ). The Mediterranean Dietary Serving Score (MDSS) is based on the latest update of the Mediterranean Diet Pyramid, using the recommended consumption frequency of foods and food groups; the MDSS ranges from 0 to 24. The discriminative power or correct subject classification capacity of the MDSS was analyzed with the Receiver Operating Characteristic (ROC) curve, using the MDS as reference method. Predictive factors for higher MDSS adherence were determined with a logistic regression model, adjusting for age. According to ROC curve analysis, MDSS evidenced a significant discriminative capacity between adherents and non-adherents to the MD pattern (optimal cutoff point=13.50; sensitivity=74%; specificity=48%). The mean MDSS was 12.45 (2.69) and was significantly higher with older age (p<0.001). Logistic regression analysis showed highest MD adherence by over 60-year-olds with low BMI and no habit of eating between meals. Conclusions The MDSS is an updated, easy, valid, and accurate instrument to assess MD adherence based on the consumption of foods and food groups per meal, day, and week. It may be useful in future nutritional education programs to prevent the early onset of chronic non-transmittable diseases in younger populations. PMID:26035442

  5. Medieval iconography of watermelons in Mediterranean Europe

    PubMed Central

    Paris, Harry S.; Daunay, Marie-Christine; Janick, Jules

    2013-01-01

    Background and Aims The watermelon, Citrullus lanatus (Cucurbitaceae), is an important fruit vegetable in the warmer regions of the world. Watermelons were illustrated in Mediterranean Antiquity, but not as frequently as some other cucurbits. Little is known concerning the watermelons of Mediterranean Europe during medieval times. With the objective of obtaining an improved understanding of watermelon history and diversity in this region, medieval drawings purportedly of watermelons were collected, examined and compared for originality, detail and accuracy. Findings The oldest manuscript found that contains an accurate, informative image of watermelon is the Tractatus de herbis, British Library ms. Egerton 747, which was produced in southern Italy, around the year 1300. A dozen more original illustrations were found, most of them from Italy, produced during the ensuing two centuries that can be positively identified as watermelon. In most herbal-type manuscripts, the foliage is depicted realistically, the plants shown as having long internodes, alternate leaves with pinnatifid leaf laminae, and the fruits are small, round and striped. The manuscript that contains the most detailed and accurate image of watermelon is the Carrara Herbal, British Library ms. Egerton 2020. In the agriculture-based manuscripts, the foliage, if depicted, is not accurate, but variation in the size, shape and coloration of the fruits is evident. Both red-flesh and white-flesh watermelons are illustrated, corresponding to the typical sweet dessert watermelons so common today and the insipid citron watermelons, respectively. The variation in watermelon fruit size, shape and coloration depicted in the illustrations indicates that at least six cultivars of watermelon are represented, three of which probably had red, sweet flesh and three of which appear to have been citrons. Evidently, citron watermelons were more common in Mediterranean Europe in the past than they are today. PMID:23904443

  6. Nutritional and cultural aspects of the Mediterranean diet.

    PubMed

    Serra-Majem, Lluis; Bach-Faig, Anna; Raidó-Quintana, Blanca

    2012-06-01

    The recent recognition by United Nations Educational, Scientific and Cultural Organization (UNESCO) of the Mediterranean diet as an Intangible Cultural Heritage of Humanity reinforces, together with the scientific evidence, the Mediterranean diet as a cultural and health model. The Mediterranean diet has numerous beneficial effects on among others the immune system, against allergies, on the psyche, or even on quality of life, topics that are currently fields of research. The Mediterranean diet has an international projection; it is regarded as the healthiest and the most sustainable eating pattern on the planet and is a key player in the public health nutrition field globally, but especially in the Mediterranean area. Moreover, this ancient cultural heritage should be preserved and promoted from different areas: public health, agriculture, culture, politics, and economic development.

  7. Phytotoxic activities of Mediterranean essential oils.

    PubMed

    de Almeida, Luiz Fernando Rolim; Frei, Fernando; Mancini, Emilia; De Martino, Laura; De Feo, Vincenzo

    2010-06-14

    Twelve essential oils from Mediterranean aromatic plants were tested for their phytotoxic activity, at different doses, against the germination and the initial radicle growth of seeds of Raphanus sativus, Lactuca sativa and Lepidium sativum. The essential oils were obtained from Hyssopus officinalis, Lavandula angustifolia, Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris (Lamiaceae), Verbena officinalis (Verbenaceae), Pimpinella anisum, Foeniculum vulgare and Carum carvi (Apiaceae). The germination and radicle growth of tested seeds were affected in different ways by the oils. Thyme, balm, vervain and caraway essential oils were more active against both germination and radicle elongation.

  8. Familial Mediterranean fever: An updated review

    PubMed Central

    Sarı, İsmail; Birlik, Merih; Kasifoğlu, Timuçin

    2014-01-01

    Familial Mediterranean Fever (FMF) is a hereditary autoinflammatory disorder characterised by acute attacks of fever and serosal inflammation. FMF primarily affects Jewish, Armenian, Turkish, and Arab populations. The disease is accompanied by a marked decrease in quality of life due to the effects of attacks and subclinical inflammation in the attack-free periods. Untreated or inadequately treated patients run the risk of amyloidosis, which is an important cause of morbidity and mortality. In this review, the current information available on FMF is summarised. PMID:27708867

  9. Phytotoxic activities of Mediterranean essential oils.

    PubMed

    de Almeida, Luiz Fernando Rolim; Frei, Fernando; Mancini, Emilia; De Martino, Laura; De Feo, Vincenzo

    2010-06-01

    Twelve essential oils from Mediterranean aromatic plants were tested for their phytotoxic activity, at different doses, against the germination and the initial radicle growth of seeds of Raphanus sativus, Lactuca sativa and Lepidium sativum. The essential oils were obtained from Hyssopus officinalis, Lavandula angustifolia, Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris (Lamiaceae), Verbena officinalis (Verbenaceae), Pimpinella anisum, Foeniculum vulgare and Carum carvi (Apiaceae). The germination and radicle growth of tested seeds were affected in different ways by the oils. Thyme, balm, vervain and caraway essential oils were more active against both germination and radicle elongation. PMID:20657443

  10. Mediterranean Holocene climate, environment and human societies

    NASA Astrophysics Data System (ADS)

    Holmgren, Karin; Gogou, Alexandra.; Izdebski, Adam.; Luterbacher, Juerg.; Sicre, Marie-Alexandrine; Xoplaki, Elena

    2016-03-01

    This paper introduces the reader to a special issue of articles that explores links and processes behind societal change, climate change and environmental change in a Holocene perspective in the Mediterranean region. All papers are, by purpose, co-authored by scientists representing different disciplines. The cross-cutting theme has been to reach beyond simple explanations of potential climate-society relationships and advance our understanding on how to improve research methods and theories in the field. The thirteen papers in this issue address these questions in three different ways, by i) conceptual/methodological approaches; ii) review papers; and iii) case studies.

  11. Study of Anticyclogenesis Affecting the Mediterranean

    NASA Astrophysics Data System (ADS)

    Hatzaki, M.; Flocas, H. A.; Simmonds, I.; Kouroutzoglou, J.; Garde, L.; Keay, K.; Bitsa, E.

    2014-12-01

    A comprehensive climatology of migratory anticyclones affecting the Mediterranean was generated by the University of Melbourne finding and tracking algorithm (MS algorithm), applied to 34 years (1979-2012) of ERA-Interim MSLP on a 1.5°x1.5° resolution. The algorithm was employed for the first time for anticyclones in this region, thus, its robustness and reliability in efficiently capturing the individual characteristics of the anticyclonic tracks in such a closed basin with complex topography were checked and verified. Then, the tracks and the statistical properties of the migratory systems were calculated and analyzed. Considering that cold-core anticyclones are shallow and weaken with height contrary to the warm-core that exhibit a vertically well-organized structure, the vertical thermal extend of the systems was studied with an algorithm developed as an extension module of the MS algorithm using ERA-Interim temperatures on several isobaric levels from 1000hPa to 100hPa on an 1.5°x1.5° resolution. The results verified that during both cold and warm period, cold-core anticyclones mainly affect the northern parts of the Mediterranean basin, with their behavior to be strongly regulated by cyclonic activity from the main storm track areas of the North Atlantic and Europe. On the other hand, warm-core anticyclones were found mainly in the southern Mediterranean and North African areas. Here, in order to get a perspective on the dynamic and thermodynamic processes in anticyclonic formation, a dynamical analysis at several vertical levels is performed. The study of mean fields of potential vorticity, temperature advection, vorticity advection at various levels can elucidate the role of upper and low levels during anticyclogenesis and system evolvement and help to further understand the dynamic mechanisms which are responsible for the anticyclogenesis over the Mediterranean region. Acknowledgement: This research project is implemented within the framework of the

  12. Enteric fever in Mediterranean north Africa.

    PubMed

    Ghenghesh, Khalifa Sifaw; Franka, Ezzedin; Tawil, Khaled; Wasfy, Momtaz O; Ahmed, Salwa F; Rubino, Salvatore; Klena, John D

    2009-01-01

    Typhoid fever is endemic in the Mediterranean North African countries (Morocco, Algeria, Tunisia, Libya, and Egypt) with an estimated incidence of 10-100 cases per 100,000 persons. Outbreaks caused by Salmonella enterica serovar Typhi are common and mainly due to the consumption of untreated or sewage-contaminated water. Salmonella enterica Paratyphi B is more commonly involved in nosocomial cases of enteric fever in North Africa than expected and leads to high mortality rates among infants with congenital anomalies. Prevalence among travellers returning from this region is low, with an estimate of less than one per 100,000. Although multidrug resistant strains of Salmonella Typhi and Paratyphi are prevalent in this region, the re-emergence of chloramphenicol- and ampicillin-susceptible strains has been observed. In order to better understand the epidemiology of enteric fever in the Mediterranean North African region, population-based studies are needed. These will assist the health authorities in the region in preventing and controlling this important disease.

  13. [Wheat, bread and pasta in Mediterranean diets].

    PubMed

    Pérez Rodrigo, Carmen; Ruiz Vadillo, Virginia

    2004-06-01

    Cereals in diets have varied along evolution trends in food patterns. Cereals are starchy foods and are the main source of polysacharides in the diet. In Mediterranean countries, cereals have been used in different ways, though they are mainly used as refined cereals. Wheat bread is one of the most commonly used. In the average Spanish diet, considerable changes have taken place since 1961 leading to a significant decrease in percent energy from carbohydrate. At the same time, percent energy from fat has increased as web as protein intake. These changes in the nutritional pattern reflect a continuous decrease in consumption of grains and cereals, pulses and potatoes. In the last decades, consumption of pasta however has increased as web as consumption of processed bakery products and biscuits. Scientific and epidemiological evidence show that cereals should be the main source of energy in the diet, in line with the so-called Mediterranean Diet. Polysacharides should provide 50-55% energy. In order to reach that goal, cereal, legumes and potatoes should be included in the daily diet as 4-6 portions. Whole grain cereales should be preferred or food preparations combining pasta, potatoes or rice with vegetables in order to reduce the glycemic index. Processed bakery products and biscuits should be consumed in moderation.

  14. Growth Dynamics in Four Mediterranean Demosponges

    NASA Astrophysics Data System (ADS)

    Garrabou, J.; Zabala, M.

    2001-03-01

    Growth dynamics of the demosponges Crambe crambe, Hemimycale columella, Oscarella lobularis and Chondrosia reniformis were studied in the north-western Mediterranean over a 2 year period. Independent growth and shrinkage rates were quantified for first time by a newly developed photographic and computer-assisted image analysis. Overall, our results indicated relatively slow growth dynamics with low growth and shrinkage rates. Interspecific comparison showed that C. crambe, H. columella and O. lobularis grew and shrank at significantly higher rates than C. reniformis (differences of over one order magnitude). Measured rates were, in general, similar to those previously reported for other species thriving in the Mediterranean, temperate and tropical habitats. Seasonal growth and shrinkage patterns were examined in C. crambe. This species showed significant differences in growth rates over time but not in shrinkage rates. Division and fusion events were observed in all species except in specimens of C. reniformis. Approximately 30% and between 14-30% of the specimens experienced division and fusion respectively. Data on growth, shrinkage, division and fusion rates were interpreted as evidence for distinct biological strategies used by these four species to persist and occupy substratum. Chondrosia reniformis had a conservative strategy, with slow growth but with greater resistance to damage. Crambe crambe seemed to enhance its rate of space occupation by a high division rate. Hemimycale columella grew quickly and shrank at low rates, thus spreading rapidly over the substratum. Finally, O. lobularis grew and shrank rapidly, showing great growth plasticity.

  15. Mediterranean Jellyfish Venoms: A Review on Scyphomedusae

    PubMed Central

    Mariottini, Gian Luigi; Pane, Luigi

    2010-01-01

    The production of natural toxins is an interesting aspect, which characterizes the physiology and the ecology of a number of marine species that use them for defence/offence purposes. Cnidarians are of particular concern from this point of view; their venoms are contained in specialized structures–the nematocysts–which, after mechanical or chemical stimulation, inject the venom in the prey or in the attacker. Cnidarian stinging is a serious health problem for humans in the zones where extremely venomous jellyfish or anemones are common, such as in temperate and tropical oceanic waters and particularly along several Pacific coasts, and severe cases of envenomation, including also lethal cases mainly induced by cubomedusae, were reported. On the contrary, in the Mediterranean region the problem of jellyfish stings is quite modest, even though they can have anyhow an impact on public health and be of importance from the ecological and economic point of view owing to the implications on ecosystems and on some human activities such as tourism, bathing and fishing. This paper reviews the knowledge about the various aspects related to the occurrence and the stinging of the Mediterranean scyphozoan jellyfish as well as the activity of their venoms. PMID:20479971

  16. Sprite climatology in the Eastern Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Yair, Yoav; Price, Colin; Katzenelson, Dor; Rosenthal, Neta; Rubanenko, Lior; Ben-Ami, Yuval; Arnone, Enrico

    2015-04-01

    We present statistical analysis of 436 sprites observed in 7 winter campaigns from 2006/7-2012/13. Results show a clear peak in the frequency of sprite detections, with maximum values (< 40% of events) between 00:30 and 02:15 LST (22:30-00:15 UT; LST = UT + 2). The detection times of sprites are well-correlated with a relative increase in the fraction of + CG strokes, which exhibit maxima between 00:00 and 02:00 LST. The morphological distribution of 339 sprites, that we were able to clearly identify, is dominated by column sprites (49.3%), with angels (33.0%) and carrots (25.7%) being less frequent. This is similar to reports of winter sprites over the Sea of Japan and summer ones in Central Europe. Other shapes such as trees, wishbones, etc. appear quite rarely. Single element events constitute 16.5% of observations, with 83.5% containing 2 elements or more. Clusters of homogenous types are slightly more frequent than mixed ones (55%). Our observations suggest winter Mediterranean thunderstorms to have a vertical structure in between high tropical convective systems and the lower cloud-top cells in Japan. The climatology shows the Eastern Mediterranean to be a major sprite producer in Northern Hemisphere winter, and offers ground-based coverage for future space missions.

  17. Sprite Climatology in the Eastern Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Yair, Yoav; Price, Colin; Katzenelson, Dor; Rosenthal, Neta; Rubanenko, Lior; Ben-Ami, Yuval; Arnone, Enrico

    2015-04-01

    We present statistical analysis of 436 sprites observed in 7 winter campaigns from 2006/7-2012/13. Results show a clear peak in the frequency of sprite detections, with maximum values (< 40% of events) between 00:30-02:15 LST (22:30-00:15 UT; LST=UT+2). The detection times of sprites are well-correlated with a relative increase in the fraction of +CG strokes, which exhibit maxima between 00:00-02:00 LST. The morphological distribution of 339 sprites, that we were able to clearly identify, is dominated by column sprites (49.3%), with angels (33.0%) and carrots (25.7%) being less frequent. This is similar to reports of winter sprites over the Sea of Japan and summer ones in central Europe. Other shapes such as trees, wishbones, etc. appear quite rarely. Single element events constitute 16.5% of observations, with 83.5% containing 2 elements or more. Clusters of homogeneous types are slightly more frequent than mixed ones (55%). Our observations suggest winter East Mediterranean thunderstorms to have a vertical structure that is an intermediate type between high tropical convective systems and the lower cloud-top cells in winter thunderstorms over the Sea of Japan. The climatology shows that the Eastern Mediterranean is a major sprite producer during Northern Hemisphere winter, and thus the existing and future optical observation infrastructure in Israel offers ground-based coverage for upcoming space missions that aim to map global sprite activity.

  18. Floating debris in the Mediterranean Sea.

    PubMed

    Suaria, Giuseppe; Aliani, Stefano

    2014-09-15

    Results from the first large-scale survey of floating natural (NMD) and anthropogenic (AMD) debris (>2 cm) in the central and western part of the Mediterranean Sea are reported. Floating debris was found throughout the entire study area with densities ranging from 0 to 194.6 items/km(2) and mean abundances of 24.9 AMD items/km(2) and 6.9 NMD items/km(2) across all surveyed locations. On the whole, 78% of all sighted objects were of anthropogenic origin, 95.6% of which were petrochemical derivatives (i.e. plastic and styrofoam). Maximum AMD densities (>52 items/km(2)) were found in the Adriatic Sea and in the Algerian basin, while the lowest densities (<6.3 items/km(2)) were observed in the Central Tyrrhenian and in the Sicilian Sea. All the other areas had mean densities ranging from 10.9 to 30.7 items/km(2). According to our calculations, more than 62 million macro-litter items are currently floating on the surface of the whole Mediterranean basin.

  19. Floating debris in the Mediterranean Sea.

    PubMed

    Suaria, Giuseppe; Aliani, Stefano

    2014-09-15

    Results from the first large-scale survey of floating natural (NMD) and anthropogenic (AMD) debris (>2 cm) in the central and western part of the Mediterranean Sea are reported. Floating debris was found throughout the entire study area with densities ranging from 0 to 194.6 items/km(2) and mean abundances of 24.9 AMD items/km(2) and 6.9 NMD items/km(2) across all surveyed locations. On the whole, 78% of all sighted objects were of anthropogenic origin, 95.6% of which were petrochemical derivatives (i.e. plastic and styrofoam). Maximum AMD densities (>52 items/km(2)) were found in the Adriatic Sea and in the Algerian basin, while the lowest densities (<6.3 items/km(2)) were observed in the Central Tyrrhenian and in the Sicilian Sea. All the other areas had mean densities ranging from 10.9 to 30.7 items/km(2). According to our calculations, more than 62 million macro-litter items are currently floating on the surface of the whole Mediterranean basin. PMID:25127501

  20. Tracking rainfall in the northern Mediterranean borderlands during sapropel deposition

    NASA Astrophysics Data System (ADS)

    Toucanne, Samuel; Angue Minto'o, Charlie Morelle; Fontanier, Christophe; Bassetti, Maria-Angela; Jorry, Stephan J.; Jouet, Gwenaël

    2015-12-01

    The role of mid-latitude precipitation in the hydrological forcing leading to the deposition of sapropels in the Mediterranean Sea remains unclear. The new GDEC-4-2 borehole, East Corsica margin (northern Tyrrhenian Sea), provides the first precisely dated evidence for enhanced rainfall in the Western Mediterranean during warm intervals of interglacial periods over the last 547 kyr. Comparison of GDEC-4-2 proxy records with pollen sequences and speleothems from the central and eastern Mediterranean reveals that these pluvial events were regional in character and occurred probably in response to the intensification of the Mediterranean storm track along the northern Mediterranean borderlands in autumn/winter. Our dataset suggests that the timing of maxima of the Mediterranean autumn/winter storm track precipitation coincide with that of the North African summer monsoon and sapropel deposition. Besides highlighting a close coupling between mid- and low-latitude hydrological changes, our findings suggest that during warm intervals of interglacial periods the reduced sea-surface water salinities, together with the high flux of nutrient and organic matter, produced by the monsoonal Nile (and wadi-systems) floods, were maintained throughout the winter by the Mediterranean rainfall. This provides an important additional constraint on the hydrological perturbation causing sapropel formation.

  1. Tubular Heart Pumping Mechanisms in Ciona Intestinalis

    NASA Astrophysics Data System (ADS)

    Battista, Nicholas; Miller, Laura

    2015-11-01

    In vertebrate embryogenesis, the first organ to form is the heart, beginning as a primitive heart tube. However, many invertebrates have tubular hearts from infancy through adulthood. Heart tubes have been described as peristaltic and impedance pumps. Impedance pumping assumes a single actuation point of contraction, while traditional peristalsis assumes a traveling wave of actuation. In addition to differences in flow, this inherently implies differences in the conduction system. It is possible to transition from pumping mechanism to the other with a change in the diffusivity of the action potential. In this work we consider the coupling between the fluid dynamics and electrophysiology of both mechanisms, within a basal chordate, the tunicate. Using CFD with a neuro-mechanical model of tubular pumping, we discuss implications of the both mechanisms. Furthermore, we discuss the implications of the pumping mechanism on evolution and development.

  2. Late Tertiary paleogeographic and tectonic evolution of the Mediterranean area

    SciTech Connect

    Arnott, R.J.; Haan, E.A.

    1988-08-01

    The present geography of the Mediterranean Sea is the result of late Tertiary tectonic processes and hardly reflects its Mesozoic and early Tertiary evolution. This paper outlines a plate tectonics model for the Mediterranean area from the Oligocene to the Pliocene. Seismic and well data have been integrated into the regional structural framework to produce a set of paleogeographic maps, which includes the Oligocene, early and middle Miocene, late Miocene, and Pliocene. These maps highlight the changes in sedimentation patterns in response to the tectonic development of the Mediterranean area. Special attention will be given to the Messinian desiccation event.

  3. Occurrence of Diopatra marocensis (Annelida, Onuphidae) in the eastern Mediterranean

    PubMed Central

    Çinar, Melih Ertan; Fauchald, Kristian; Dagli, Ertan

    2014-01-01

    Abstract The present study deals with the presence of Diopatra marocensis in the eastern Mediterranean. This species is small-sized and inhabited muddy bottom near the opening of rivers or lagoons [salinity range: 33−39‰] in the Aegean and Levantine Seas, and reached a maximum density of 90 ind.m-2 in Mersin Bay. This species might be an alien species that was introduced from the East Atlantic (near Gibraltar) to the eastern Mediterranean via ballast water of ships, as it has never been reported from the western Mediterranean Sea. PMID:25349504

  4. Occurrence of Diopatramarocensis (Annelida, Onuphidae) in the eastern Mediterranean.

    PubMed

    Cinar, Melih Ertan; Fauchald, Kristian; Dagli, Ertan

    2014-01-01

    The present study deals with the presence of Diopatramarocensis in the eastern Mediterranean. This species is small-sized and inhabited muddy bottom near the opening of rivers or lagoons [salinity range: 33-39‰] in the Aegean and Levantine Seas, and reached a maximum density of 90 ind.m(-2) in Mersin Bay. This species might be an alien species that was introduced from the East Atlantic (near Gibraltar) to the eastern Mediterranean via ballast water of ships, as it has never been reported from the western Mediterranean Sea.

  5. Is the Chilean diet a Mediterranean-type diet?

    PubMed

    Rozowski, Jaime; Castillo, Oscar

    2004-01-01

    Food intake in Chile has changed markedly in the last decades, showing an increase in fat consumption and presently a small fruit and vegetables intake. A parallel is made between the Chilean and Mediterranean diet (mainly the one from Spain, Italy, and Greece), both currently and from 50 years ago. The main differences and similarities are based on food availability. Although Chilean diet seems to be approaching the traditional Mediterranean diet of the 60's, there is concern about changes that are moving away from Chilean traditional diet and towards a western one. A new food pyramid for Chile is proposed based on the traditional Mediterranean-type diet.

  6. Longitudinal variability of the biogeochemical role of Mediterranean aerosols in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Ternon, E.; Guieu, C.; Ridame, C.; L'Helguen, S.; Catala, P.

    2010-11-01

    The Mediterranean Sea is a semi-enclosed basin characterized by a strong thermal stratification during summer during which the atmosphere is the main source of new nutrients to the nutrient-depleted surface layer. From aerosol sampling and microcosm experiments performed during the TransMed BOUM cruise (June-July 2008) we showed that: (i) the Mediterranean atmosphere composition (Al, Fe, P) was homogeneous over ~28° of longitude and was a mixture with a constant proportion of anthropogenic contribution and a variable but modest contribution of crustal aerosols. This quite stable composition over a one month period and a long transect (~2500 km) allowed to define the Mediterranean atmospheric "background" that characterizes the summer season in the absence of major Saharan event and forest fires, (ii) primary production significantly increased at all tested stations after aerosols addition collected on-board and after Saharan dust analog addition, indicating that both additions relieved on-going (co)-limitations. Although both additions significantly increased the N2 fixation rates at the western station, diazotrophic activity remained very low (~0.2 nmol N L-1 d-1), (iii) due to the presence of anthropogenic particles, the probable higher solubility of nutrients associated with mixed aerosols (crustal + anthropogenic contribution), conferred a higher fertilizing potential to on-board collected aerosol as compared to Saharan dust analog. Finally, those experiments showed that atmospheric inputs from a mixed atmospheric event ("summer rain" type) or from a high-intensity Saharan event would induce comparable response by the biota in the stratified Mediterranean SML, during summer.

  7. Longitudinal variability of the biogeochemical role of Mediterranean aerosols in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Ternon, E.; Guieu, C.; Ridame, C.; L'Helguen, S.; Catala, P.

    2011-05-01

    The Mediterranean Sea is a semi-enclosed basin characterized by a strong thermal stratification during summer during which the atmosphere is the main source of new nutrients to the nutrient-depleted surface layer. From aerosol sampling and microcosm experiments performed during the TransMed BOUM cruise (June-July 2008) we showed that: (i) the Mediterranean atmosphere composition (Al, Fe, P) was homogeneous over ~28° of longitude and was a mixture with a constant proportion of anthropogenic contribution and a variable but modest contribution of crustal aerosols. This quite stable composition over a one month period and a long transect (~2500 km) allowed to define the Mediterranean atmospheric "background" that characterizes the summer season in the absence of major Saharan event and forest fires, (ii) primary production significantly increased at all tested stations after aerosols addition collected on-board and after Saharan dust analog addition, indicating that both additions relieved on-going (co)-limitations. Although both additions significantly increased the N2 fixation rates at the western station, diazotrophic activity remained very low (~0.2 nmol N L-1 d-1), (iii) due to the presence of anthropogenic particles, the probable higher solubility of nutrients associated with mixed aerosols (crustal + anthropogenic contribution), conferred a higher fertilizing potential to on-board collected aerosol as compared to Saharan dust analog. Finally, those experiments showed that atmospheric inputs from a mixed atmospheric event ("summer rain" type) or from a high-intensity Saharan event would induce comparable response by the biota in the stratified Mediterranean SML, during summer.

  8. Diversity, distribution and population size structure of deep Mediterranean gorgonian assemblages (Menorca Channel, Western Mediterranean Sea)

    NASA Astrophysics Data System (ADS)

    Grinyó, Jordi; Gori, Andrea; Ambroso, Stefano; Purroy, Ariadna; Calatayud, Clara; Dominguez-Carrió, Carlos; Coppari, Martina; Lo Iacono, Claudio; López-González, Pablo J.; Gili, Josep-Maria

    2016-06-01

    Gorgonians are a key group of organisms in benthic marine communities with a wide bathymetric and geographical distribution. Although their presence on continental shelves and slopes has been known for more than 100 years, knowledge concerning the ecology of deep gorgonian species is still in a very preliminary stage. To overcome this situation, gorgonian assemblages located at 40-360 m depth were studied over a large geographical area on the continental shelf and upper slope of the Menorca Channel (Western Mediterranean Sea). A quantitative analysis of video transects recorded by a manned submersible and a remotely operated vehicle, were used to examine the diversity, distribution and demography of gorgonian species. Results showed high gorgonian diversity within this depth range (a total of nine species were observed) compared to Mediterranean coastal areas. Gorgonian assemblages on the continental shelf and upper slope were mostly monospecific (respectively 73% and 76% of occupied sampling units contained one single species), whereas shelf edge assemblages were highly multispecific (92% of occupied sampling units contained several species). This contrasts with the monospecificity of Mediterranean coastal gorgonian assemblages. Gorgonian populations on the continental shelf were mostly dominated by small colonies (88% of measured colonies) with few intermediate and large colonies (12% of measured colonies). In deeper areas small colonies were still dominant (60% of measured colonies), but intermediate and large colonies were much more abundant (40% of measured colonies). This suggests high recruitment rates on the continental shelf, but perturbations (trammel nets, long lines and strong storms) may limit the presence of intermediate and large colonies. Conversely, on the shelf edge and upper slope a more stable environment may allow colonies to reach larger dimensions. The identification and ecological characterization of these deep assemblages further extends

  9. The Mediterranean Forecasting System: recent developments

    NASA Astrophysics Data System (ADS)

    Tonani, Marina; Oddo, Paolo; Korres, Gerasimos; Clementi, Emanuela; Dobricic, Srdjan; Drudi, Massimiliano; Pistoia, Jenny; Guarnieri, Antonio; Romaniello, Vito; Girardi, Giacomo; Grandi, Alessandro; Bonaduce, Antonio; Pinardi, Nadia

    2014-05-01

    Recent developments of the Mediterranean Monitoring and Forecasting Centre of the EU-Copernicus marine service, the Mediterranean Forecasting System (MFS), are presented. MFS provides forecast, analysis and reanalysis for the physical and biogeochemical parameters of the Mediterranean Sea. The different components of the system are continuously updated in order to provide to the users the best available product. This work is focus on the physical component of the system. The physical core of MFS is composed by an ocean general circulation model (NEMO) coupled with a spectral wave model (Wave Watch-III). The NEMO model provides to WW-III surface currents and SST fields, while WW-III returns back to NEMO the neutral component of the surface drag coefficient. Satellite Sea Level Anomaly observations and in-situ T & S vertical profiles are assimilated into this system using a variational assimilation scheme based on 3DVAR (Dobricic, 2008) . Sensitive experiments have been performed in order to assess the impact of the assimilation of the latest available SLA missions, Altika and Cryosat together with the long term available mission of Jason2. The results show a significant improvement of the MFS skill due to the multi-mission along track assimilation. The primitive equations module has been recently upgraded with the introduction of the atmospheric pressure term and a new, explicit, numerical scheme has been adopted to solve the barotropic component of the equations of motion. The SLA satellite observations for data assimilation have been consequently modified in order to account for the new atmospheric pressure term introduced in the equations. This new system has been evaluated using tide gauge coastal buoys and the satellite along track data. The quality of the SSH has improved significantly while a minor impact has been observed on the other state variables (temperature, salinity and currents). Experiments with a higher resolution NWP (numerical weather prediction

  10. Ischemic heart disease and the Mediterranean diet.

    PubMed

    Whayne, Thomas F

    2014-01-01

    Lifestyle modification is primary in cardiovascular (CV) disease prevention. A major contribution is the Mediterranean diet (MedDiet), defined by two of seven components. Italian investigators determined a significant decrease in peripheral arterial disease of 56 % for a high score. Multiple specific CV risk factors are also favorably modified by the MedDiet. This includes beneficial effect on inflammation, vascular endothelium, and insulin resistance. There is also evidence that coronary heart disease, diabetes mellitus, and metabolic syndrome are decreased. Benefit appears to extend to new migrants in France. The economics of dietary adherence are favorable with decreased total lifetime health costs. Although mixed nuts appear to be a major factor in the MedDiet, special emphasis goes to extra virgin olive oil. Benefit also extends to other noncommunicable diseases with a decrease in cancer, Parkinson's disease, and Alzheimer's disease. Further quantitation of benefit and understanding of mechanisms involved in dietary benefit is essential. PMID:24743900

  11. Barotropic coastal currents in the Mediterranean

    SciTech Connect

    Piacsek, S.A.; Allard, R.

    1994-12-31

    In the winter-spring season many areas of the Mediterranean become weakly stratified and in shallow areas nearly homogeneous, thus increasing the barotropic contribution of the wind-driven circulation. Furthermore, the sea level changes and flows through the straits are strongly coupled to the atmospheric pressure changes over diurnal and weekly time scales, such flows being predominantly barotropic. An added impetus to revisit the barotropic response is the recent availability of synoptic winds and pressure fields with 45 km resolution. In this paper the authors have studied the barotropic response with a 1-layer free surface numerical model for the period September 1992 to April 1993 with 6-hourly synoptic winds. The model and topography resolution was 3.5 km, and the coefficient of horizontal friction was varied between 10 and 50m{sup 2}/sec. Emphasis is on flows near coasts and in straits.

  12. Sclerites in different tissues of Mediterranean Echinodermata.

    PubMed

    Ocaña Martín, Amelia; Tierno de Figueroa, J Manuel; Palomino-Morales, Rogelio J

    2006-06-01

    The presence of sclerites in different mesodermal tissues was studied in thirteen species of Mediterranean echinoderms representing the five living classes. In the species of Asteroidea and Crinoidea examined, sclerites were present only in specific tissues. In the species of Ophiuroidea and, especially, Echinoidea and Holothuroidea examined, sclerites were present in almost every tissue, but with considerable variation among species and tissues. Data on sclerite shape, size, and relative abundance (measured as tissue abundance) are presented. The data support the possible functional role of sclerites as reinforcing structures, as well as their possible use as taxonomic characters. Finally, the need of more studies to elucidate the ontogenetic and phylogenetic implications of sclerites is discussed.

  13. [Water problems in the Eastern Mediterranean Region].

    PubMed

    Zeribl, T

    2005-01-01

    The Eastern Mediterranean Region of the World Health Organization is confronted with formidable water problems due to: increased water demand both for consumption and for irrigation in agriculture that is becoming more productive and more polluting; scarce water resources; drought, erosion and pollution; inappropriate management; inadequate policies; and institutional and legal considerations. Added to these problems are the risks of regional conflicts because of the lack of "shared" management of cross-border waters which are an object of contention between neighbouring countries. This report analyses the issues relating to water availability, health and development on the basis of the distribution of water resources, and their use by industry and the huge proportion for agricultural use. It raises the question whether countries in the Region are ready to review their strategies on water priorities, particularly in the areas of health, agriculture and food self-sufficiency. PMID:16532689

  14. Least Disturbed Condition for European Mediterranean rivers.

    PubMed

    Feio, M J; Aguiar, F C; Almeida, S F P; Ferreira, J; Ferreira, M T; Elias, C; Serra, S R Q; Buffagni, A; Cambra, J; Chauvin, C; Delmas, F; Dörflinger, G; Erba, S; Flor, N; Ferréol, M; Germ, M; Mancini, L; Manolaki, P; Marcheggiani, S; Minciardi, M R; Munné, A; Papastergiadou, E; Prat, N; Puccinelli, C; Rosebery, J; Sabater, S; Ciadamidaro, S; Tornés, E; Tziortzis, I; Urbanič, G; Vieira, C

    2014-04-01

    The present report describes a three-step approach that was used to characterize and define thresholds for the Least Disturbed Condition in Mediterranean streams of four different types, regarding organic pollution and nutrients, hydrological and morphological alterations, and land use. For this purpose, a common database composed of national reference sites (929 records) from seven countries, sampled for invertebrates, diatoms and macrophytes was used. The analyses of reference sites showed that small (catchment <100 km(2)) siliceous and non-siliceous streams were mainly affected by channelization, bank alteration and hydropeaking. Medium-sized siliceous rivers were the most affected by stressors: 25-43% of the samples showed at least slight alterations regarding channelization, connectivity, upstream dam influence, hydropeaking and degradation of riparian vegetation. Temporary streams were the least affected by hydromorphological changes, but they were nevertheless affected by alterations in riparian vegetation. There were no major differences between all permanent stream types regarding water quality, but temporary streams showed lower values for oxygenation (DO) and wider ranges for other variables, such as nitrates. A lower threshold value for DO (60%) was determined for this stream type and can be attributed to the streams' natural characteristics. For all other river types, common limits were found for the remaining variables (ammonium, nitrate, phosphate, total P, % of artificial areas, % of intensive and extensive agriculture, % of semi-natural areas in the catchment). These values were then used to select the list of reference sites. The biological communities were characterized, revealing the existence of nine groups of Mediterranean invertebrate communities, six for diatoms and five for macrophytes: each group was characterized by specific indicator taxa that highlighted the differences between groups. PMID:23791044

  15. Celiac disease in the Mediterranean area

    PubMed Central

    2014-01-01

    Background The World Gastroenterology Organization recommends developing national guidelines for the diagnosis of Celiac Disease (CD): hence a profile of the diagnosis of CD in each country is required. We aim to describe a cross-sectional picture of the clinical features and diagnostic facilities in 16 countries of the Mediterranean basin. Since a new ESPGHAN diagnostic protocol was recently published, our secondary aim is to estimate how many cases in the same area could be identified without a small intestinal biopsy. Methods By a stratified cross-sectional retrospective study design, we examined clinical, histological and laboratory data from 749 consecutive unselected CD children diagnosed by national referral centers. Results The vast majority of cases were diagnosed before the age of 10 (median: 5 years), affected by diarrhea, weight loss and food refusal, as expected. Only 59 cases (7.8%) did not suffer of major complaints. Tissue transglutaminase (tTG) assay was available, but one-third of centers reported financial constraints in the regular purchase of the assay kits. 252 cases (33.6%) showed tTG values over 10 times the local normal limit. Endomysial antibodies and HLA typing were routinely available in only half of the centers. CD was mainly diagnosed from small intestinal biopsy, available in all centers. Based on these data, only 154/749 cases (20.5%) would have qualified for a diagnosis of CD without a small intestinal biopsy, according to the new ESPGHAN protocol. Conclusions This cross-sectional study of CD in the Mediterranean referral centers offers a puzzling picture of the capacities to deal with the emerging epidemic of CD in the area, giving a substantive support to the World Gastroenterology Organization guidelines. PMID:24517104

  16. Least Disturbed Condition for European Mediterranean rivers.

    PubMed

    Feio, M J; Aguiar, F C; Almeida, S F P; Ferreira, J; Ferreira, M T; Elias, C; Serra, S R Q; Buffagni, A; Cambra, J; Chauvin, C; Delmas, F; Dörflinger, G; Erba, S; Flor, N; Ferréol, M; Germ, M; Mancini, L; Manolaki, P; Marcheggiani, S; Minciardi, M R; Munné, A; Papastergiadou, E; Prat, N; Puccinelli, C; Rosebery, J; Sabater, S; Ciadamidaro, S; Tornés, E; Tziortzis, I; Urbanič, G; Vieira, C

    2014-04-01

    The present report describes a three-step approach that was used to characterize and define thresholds for the Least Disturbed Condition in Mediterranean streams of four different types, regarding organic pollution and nutrients, hydrological and morphological alterations, and land use. For this purpose, a common database composed of national reference sites (929 records) from seven countries, sampled for invertebrates, diatoms and macrophytes was used. The analyses of reference sites showed that small (catchment <100 km(2)) siliceous and non-siliceous streams were mainly affected by channelization, bank alteration and hydropeaking. Medium-sized siliceous rivers were the most affected by stressors: 25-43% of the samples showed at least slight alterations regarding channelization, connectivity, upstream dam influence, hydropeaking and degradation of riparian vegetation. Temporary streams were the least affected by hydromorphological changes, but they were nevertheless affected by alterations in riparian vegetation. There were no major differences between all permanent stream types regarding water quality, but temporary streams showed lower values for oxygenation (DO) and wider ranges for other variables, such as nitrates. A lower threshold value for DO (60%) was determined for this stream type and can be attributed to the streams' natural characteristics. For all other river types, common limits were found for the remaining variables (ammonium, nitrate, phosphate, total P, % of artificial areas, % of intensive and extensive agriculture, % of semi-natural areas in the catchment). These values were then used to select the list of reference sites. The biological communities were characterized, revealing the existence of nine groups of Mediterranean invertebrate communities, six for diatoms and five for macrophytes: each group was characterized by specific indicator taxa that highlighted the differences between groups.

  17. Visceral Leishmaniasis and HIV Coinfection in the Mediterranean Region

    PubMed Central

    Monge-Maillo, Begoña; Norman, Francesca F.; Cruz, Israel; Alvar, Jorge; López-Vélez, Rogelio

    2014-01-01

    Visceral leishmaniasis is hypoendemic in Mediterranean countries, where it is caused by the flagellate protozoan Leishmania infantum. VL cases in this area account for 5%–6% of the global burden. Cases of Leishmania/HIV coinfection have been reported in the Mediterranean region, mainly in France, Italy, Portugal, and Spain. Since highly active antiretroviral therapy was introduced in 1997, a marked decrease in the number of coinfected cases in this region has been reported. The development of new diagnostic methods to accurately identify level of parasitemia and the risk of relapse is one of the main challenges in improving the treatment of coinfected patients. Clinical trials in the Mediterranean region are needed to determine the most adequate therapeutic options for Leishmania/HIV patients as well as the indications and regimes for secondary prophylaxis. This article reviews the epidemiological, diagnostic, clinical, and therapeutic aspects of Leishmania/HIV coinfection in the Mediterranean region. PMID:25144380

  18. Type 2 diabetes: Mediterranean diet delays need for drug therapy.

    PubMed

    2015-09-01

    According to a trial in patients with recently diagnosed type 2 diabetes, adopting a "Mediterranean" diet seems to delay the need for glucose-lowering drugs by several years compared with a low-fat diet.

  19. Cognitive health and Mediterranean diet: just diet or lifestyle pattern?

    PubMed

    Yannakoulia, Mary; Kontogianni, Meropi; Scarmeas, Nikolaos

    2015-03-01

    Mediterranean diet is a term used to describe the traditional eating habits of people in Crete, South Italy and other Mediterranean countries. It is a predominantly plant-based diet, with olive oil being the main type of added fat. There are many observational studies exploring the potential association between adherence to the Mediterranean diet and cognitive decline. The present review focuses on longitudinal studies with repeated cognitive assessments. It also evaluates evidence on behaviors related to the Mediterranean way of living, that have been shown to be associated with cognition, namely social interaction, participation in leisure activities, including physical activities, and sleep quality. The synergistic association-effect of these lifestyle behaviors, including diet, is unknown. Lifestyle patterns may constitute a new research and public health perspective. PMID:25461244

  20. Toward homogenization of Mediterranean lagoons and their loss of hydrodiversity

    NASA Astrophysics Data System (ADS)

    Ferrarin, Christian; Bajo, Marco; Bellafiore, Debora; Cucco, Andrea; De Pascalis, Francesca; Ghezzo, Michol; Umgiesser, Georg

    2014-08-01

    Lagoons are considered to be the most valuable systems of the Mediterranean coastal area, with crucial ecological, historical, economical, and social relevance. Climate change strongly affects coastal areas and can deeply change the status of transitional areas like lagoons. Herein we investigate the hydrological response of 10 Mediterranean lagoons to climate change by means of numerical models. Our results suggest that Mediterranean lagoons amplify the salinity and temperature changes expected for the open sea. Moreover, numerical simulations indicate that there will be a general loss of intralagoon and interlagoon variability of their physical properties. Therefore, as a result of climate change, we see on Mediterranean lagoons an example of a common process that in future may effect many coastal environments: that of homogenization of the physical characteristics with a tendency toward marinization.

  1. The Mediterranean interannual variability in MEDRYS, a Mediterranean Sea reanalysis over 1992-2013

    NASA Astrophysics Data System (ADS)

    Beuvier, Jonathan; Hamon, Mathieu; Lellouche, Jean-Michel; Greiner, Eric; Alias, Antoinette; Arsouze, Thomas; Benkiran, Mounir; Béranger, Karine; Drillet, Yann; Sevault, Florence; Somot, Samuel

    2015-04-01

    The French research community on the Mediterranean Sea and the French operational ocean forecasting center Mercator Océan are gathering their skills and expertises in physical oceanography, ocean modelling, atmospheric forcings and data assimilation, to carry out a MEDiterranean Sea ReanalYsiS (MEDRYS) at high resolution for the period 1992-2013. The reanalysis is used to have a realistic description of the ocean state over the recent decades and it will help to understand the long-term water cycle over the Mediterranean basin in terms of variability and trends, contributing thus to the HyMeX international program. The ocean model used is NEMOMED12 [Lebeaupin Brossier et al., 2011, Oc. Mod., 2012, Oc. Mod.; Beuvier et al., 2012a, JGR, 2012b, Mercator Newsl.], a Mediterranean configuration of NEMO [Madec and the NEMO Team, 2008], with a 1/12° (about 7 km) horizontal resolution and 75 vertical z-levels with partial steps. It is forced by the 3-hourly atmospheric fluxes coming from an ALADIN-Climate simulation at 12 km of resolution [Herrmann et al., 2011, NHESS], driven by the ERA-Interim atmospheric reanalysis. The exchanges with the Atlantic Ocean are performed through a buffer zone, with a damping on 3D theta-S and on sea level towards the ORA-S4 oceanic reanalysis [Balmaseda et al., 2012, QJRMS]. This model configuration is used to carry a 34-year free simulation over the period 1979-2013. This free simulation is the initial state of the reanalysis in October 1992. It is also used to compute anomalies from which the data assimilation scheme derives required characteristic covariances of the ocean model. MEDRYS1 uses the current Mercator Océan operational data assimilation system [Lellouche et al., 2013, Oc.Sci.]. It uses a reduced order Kalman filter with a 3D multivariate modal decomposition of the forecast error. A 3D-Var scheme corrects biases in temperature and salinity for the slowly evolving large-scale. In addition, some modifications dedicated to the

  2. Climatic factors in resurgence of Mediterranean spotted fever

    SciTech Connect

    Arenas, E.E.; Creus, B.F.; Cueto, F.B.; Porta, F.S.

    1986-06-07

    There has been a recent resurgence of Mediterranean spotted fever in areas bordering the Mediterranean Sea. This disease is caused by Rickettsia conorii, the dog tick being the vector and main reservoir. Ticks prefer warm weather and their activity increases with rising temperature. In the Valles Occidental, Spain, the incidence of the disease is correlated with hotter and drier summers in the past ten years.

  3. Alkalinity and carbon budgets in the Mediterranean Sea

    SciTech Connect

    Copin-Montegut, C. )

    1993-12-01

    The carbon budget of the Mediterranean Sea has never been assessed. This paper reports the results of numerous measurements of pH and alkalinity in the spring of 1991. This concentration in inorganic carbon was deduced from the measurements. The existence of simple relationships between alkalinity and salinity or inorganic carbon and salinity made it possible to assess the budget of alkalinity and carbon in the Mediterranean Sea. 55 refs., 4 figs., 4 tabs.

  4. Miocene to Pleistocene osmium isotopic records of the Mediterranean sediments

    NASA Astrophysics Data System (ADS)

    Kuroda, Junichiro; Jiménez-Espejo, Francisco J.; Nozaki, Tatsuo; Gennari, Rocco; Lugli, Stefano; Manzi, Vinicio; Roveri, Marco; Flecker, Rachel; Sierro, Francisco J.; Yoshimura, Toshihiro; Suzuki, Katsuhiko; Ohkouchi, Naohiko

    2016-01-01

    In the late Miocene the Mediterranean Sea experienced a salinity crisis and thick sequences of evaporites precipitated across the deep and marginal basins. In this study we report Os isotopic records from Deep Sea Drilling Project and Ocean Drilling Project cores in the Mediterranean: the Balearic Sea (Site 372), the Tyrrhenian Sea (Site 654), the Ionian Basin (Site 374), and the Florence Rise (Sites 375-376), as well as Integrated Ocean Drilling Project Site U1387 in Gulf of Cadiz, North Atlantic. Pliocene-Pleistocene sediments at all sites show 187Os/188Os values close to that of the coeval ocean water, indicating that the Mediterranean was connected to the North Atlantic. Evaporitic sediments deposited during the latest Miocene, however, have 187Os/188Os values significantly lower than coeval ocean water values. The offset of the Mediterranean evaporite 187Os/188Os is attributed to limited exchange with the North Atlantic during the Messinian salinity crisis. The source of unradiogenic Os is likely to be weathering of ultramafic rocks (ophiolites) cropping out in the Mediterranean's drainage basins. Based on a box model we estimated the amount of unradiogenic Os and the Atlantic-Mediterranean exchange rate to explain this offset. Os isotopic ratios of the pre-evaporite sediments in the western Mediterranean are almost identical to that of the coeval ocean water. In contrast, equivalent sediments from the Florence Rise have significantly lower 187Os/188Os values. The offset in the Os isotopic ratio on the Florence Rise is attributed either to limited water exchange between eastern and western Mediterranean or to local effects associated with exhumation of the Troodos ophiolites (Cyprus).

  5. A phylogenetic perspective on the evolution of Mediterranean teleost fishes.

    PubMed

    Meynard, Christine N; Mouillot, David; Mouquet, Nicolas; Douzery, Emmanuel J P

    2012-01-01

    The Mediterranean Sea is a highly diverse, highly studied, and highly impacted biogeographic region, yet no phylogenetic reconstruction of fish diversity in this area has been published to date. Here, we infer the timing and geographic origins of Mediterranean teleost species diversity using nucleotide sequences collected from GenBank. We assembled a DNA supermatrix composed of four mitochondrial genes (12S ribosomal DNA, 16S ribosomal DNA, cytochrome c oxidase subunit I and cytochrome b) and two nuclear genes (rhodopsin and recombination activating gene I), including 62% of Mediterranean teleost species plus 9 outgroups. Maximum likelihood and Bayesian phylogenetic and dating analyses were calibrated using 20 fossil constraints. An additional 124 species were grafted onto the chronogram according to their taxonomic affinity, checking for the effects of taxonomic coverage in subsequent diversification analyses. We then interpreted the time-line of teleost diversification in light of Mediterranean historical biogeography, distinguishing non-endemic natives, endemics and exotic species. Results show that the major Mediterranean orders are of Cretaceous origin, specifically ~100-80 Mya, and most Perciformes families originated 80-50 Mya. Two important clade origin events were detected. The first at 100-80 Mya, affected native and exotic species, and reflects a global diversification period at a time when the Mediterranean Sea did not yet exist. The second occurred during the last 50 Mya, and is noticeable among endemic and native species, but not among exotic species. This period corresponds to isolation of the Mediterranean from Indo-Pacific waters before the Messinian salinity crisis. The Mediterranean fish fauna illustrates well the assembly of regional faunas through origination and immigration, where dispersal and isolation have shaped the emergence of a biodiversity hotspot. PMID:22590545

  6. The Mediterranean and Black Sea Fisheries at Risk from Overexploitation

    PubMed Central

    Tsikliras, Athanassios C.; Dinouli, Anny; Tsiros, Vasileios-Zikos; Tsalkou, Eleni

    2015-01-01

    The status of the Mediterranean and Black Sea fisheries was evaluated for the period 1970-2010 on a subarea basis, using various indicators including the temporal variability of total landings, the number of recorded stocks, the mean trophic level of the catch, the fishing-in-balance index and the catch-based method of stock classification. All indicators confirmed that the fisheries resources of the Mediterranean and Black Sea are at risk from overexploitation. The pattern of exploitation and the state of stocks differed among the western (W), central (C) and eastern (E) Mediterranean subareas and the Black Sea (BS), with the E Mediterranean and BS fisheries being in a worst shape. Indeed, in the E Mediterranean and the BS, total landings, mean trophic level of the catch and fishing-in-balance index were declining, the cumulative percentage of overexploited and collapsed stocks was higher, and the percentage of developing stocks was lower, compared to the W and C Mediterranean. Our results confirm the need for detailed and extensive stock assessments across species that will eventually lead to stocks recovering through conservation and management measures. PMID:25793975

  7. Extra-Mediterranean refugia: The rule and not the exception?

    PubMed Central

    2012-01-01

    Some decades ago, biogeographers distinguished three major faunal types of high importance for Europe: (i) Mediterranean elements with exclusive glacial survival in the Mediterranean refugia, (ii) Siberian elements with glacial refugia in the eastern Palearctic and only postglacial expansion to Europe and (iii) arctic and/or alpine elements with large zonal distributions in the periglacial areas and postglacial retreat to the North and/or into the high mountain systems. Genetic analyses have unravelled numerous additional refugia both of continental and Mediterranean species, thus strongly modifying the biogeographical view of Europe. This modified notion is particularly true for the so-called Siberian species, which in many cases have not immigrated into Europe during the postglacial period, but most likely have survived the last, or even several glacial phases, in extra-Mediterranean refugia in some climatically favourable but geographically limited areas of southern Central and Eastern Europe. Recently, genetic analyses revealed that typical Mediterranean species have also survived the Last Glacial Maximum in cryptic northern refugia (e.g. in the Carpathians or even north of the Alps) in addition to their Mediterranean refuge areas. PMID:22953783

  8. The Mediterranean and Black Sea fisheries at risk from overexploitation.

    PubMed

    Tsikliras, Athanassios C; Dinouli, Anny; Tsiros, Vasileios-Zikos; Tsalkou, Eleni

    2015-01-01

    The status of the Mediterranean and Black Sea fisheries was evaluated for the period 1970-2010 on a subarea basis, using various indicators including the temporal variability of total landings, the number of recorded stocks, the mean trophic level of the catch, the fishing-in-balance index and the catch-based method of stock classification. All indicators confirmed that the fisheries resources of the Mediterranean and Black Sea are at risk from overexploitation. The pattern of exploitation and the state of stocks differed among the western (W), central (C) and eastern (E) Mediterranean subareas and the Black Sea (BS), with the E Mediterranean and BS fisheries being in a worst shape. Indeed, in the E Mediterranean and the BS, total landings, mean trophic level of the catch and fishing-in-balance index were declining, the cumulative percentage of overexploited and collapsed stocks was higher, and the percentage of developing stocks was lower, compared to the W and C Mediterranean. Our results confirm the need for detailed and extensive stock assessments across species that will eventually lead to stocks recovering through conservation and management measures.

  9. Multi-Model approach to reconstruct the Mediterranean Freshwater Evolution

    NASA Astrophysics Data System (ADS)

    Simon, Dirk; Marzocchi, Alice; Flecker, Rachel; Lunt, Dan; Hilgen, Frits; Meijer, Paul

    2016-04-01

    Today the Mediterranean Sea is isolated from the global ocean by the Strait of Gibraltar. This restricted nature causes the Mediterranean basin to react more sensitively to climatic and tectonic related phenomena than the global ocean. Not just eustatic sea-level and regional river run-off, but also gateway tectonics and connectivity between sub-basins are leaving an enhanced fingerprint in its geological record. To understand its evolution, it is crucial to understand how these different effects are coupled. The Miocene-Pliocene sedimentary record of the Mediterranean shows alternations in composition and colour and has been astronomically tuned. Around the Miocene-Pliocene Boundary the most extreme changes occur in the Mediterranean Sea. About 6% of the salt in the global ocean deposited in the Mediterranean Region, forming an approximately 2 km thick salt layer, which is still present today. This extreme event is named the Messinian Salinity Crisis (MSC, 5.97-5.33 Ma). The gateway and climate evolution is not well constrained for this time, which makes it difficult to distinguish which of the above mentioned drivers might have triggered the MSC. We, therefore, decided to tackle this problem via a multi-model approach: (1) We calculate the Mediterranean freshwater evolution via 30 atmosphere-ocean-vegetation simulations (using HadCM3L), to which we fitted to a function, using a regression model. This allows us to directly relate the orbital curves to evaporation, precipitation and run off. The resulting freshwater evolution can be directly correlated to other sedimentary and proxy records in the late Miocene. (2) By feeding the new freshwater evolution curve into a box/budget model we can predict the salinity and strontium evolution of the Mediterranean for a certain Atlantic-Mediterranean gateway. (3) By comparing these results to the known salinity thresholds of gypsum and halite saturation of sea water, but also to the late Miocene Mediterranean strontium

  10. TERENO-MED: Terrestrial Environmental Observatories in the Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Krueger, Elisabeth; Friesen, Jan; Kallioras, Andreas; Bogena, Heye; Devaraju, Anusuriya; Vereecken, Harry; Teutsch, Georg

    2013-04-01

    The Mediterranean region is one of the most imperilled regions in the world concerning present and future water scarcity. The region is delicately positioned at the crossroads between East and West, interlinking Europe, Asia and Africa. Societal and economic changes causing population growth, industrialisation and urbanisation lead to significant increases in food, water and energy demand. Hence, natural resources, such as water and soils, as well as ecosystems are put under pressure and water availability and quality will be severely affected in the future. At the same time, climate and extreme event projections from climate models for the Mediterranean are, unlike for most regions worldwide, consistent in their trends based on various scenarios. This consistency in the model predictions shows that the Mediterranean will face some of the most severe increases in dryness worldwide (based on consecutive dry days and soil moisture), and indicate a decrease of up to 50 % in available water resources within the next 50-100 years. These developments are accentuated by the fact that in many of the Mediterranean countries, natural renewable water resources are fully exploited or over-exploited already today, mainly due to agricultural irrigation, but also touristic activities. At the same time, the Mediterranean region is a global hot spot of freshwater biodiversity, with a high proportion of endemic and endangered species. While trend projections for water availability and climate change derived from global studies are consistent, regional patterns and heterogeneities, as well as local adaptation measures will largely determine the functioning of societies and the health of ecosystems. However, a lack of environmental data prohibits the development of sustainable adaptation measures to water scarcity on a scientific basis. Building on the experiences gained in the national TERENO network, a Mediterranean observatory network will be set-up, coordinated by two Helmholtz

  11. Observing Mean Annual Mediterranean Maquis Ecosystem Respiration

    NASA Astrophysics Data System (ADS)

    Marras, S.; Bellucco, V.; Mereu, S.; Sirca, C.; Spano, D.

    2014-12-01

    In semi arid ecosystems, extremely low Soil Water Content (SWC) values may limit ecosystem respiration (Reco) to the point of hiding the typical exponential response of respiration to temperature. This work is aimed to understand and model the Reco of an evergreen Mediterranean maquis ecosystem and to estimate the contribution of soil CO2 efflux to Reco. The selected site is located in the center of the Mediterranean sea in Sardinia (Italy). Mean annual precipitation is 588 mm and mean annual temperature is 15.9 °C. Vegetation cover is heterogeneous: 70% covered by shrubs and 30% of bare soil. Net Ecosystem Exchange (NEE) is monitored with an Eddy Covariance (EC) tower since April 2004. Soil collars were placed underneath the dominant species (Juniperus phoenicea and Pistacia lentiscus) and over the bare soil. Soil CO2 efflux was measured once a month since April 2012. Soil temperature and SWC were monitored continuously at 5 cm depth in 4 different positions close to the soil collars. Six years of EC measurements (2005-2010) and two years of soil CO2 efflux (2012-2013) measurements were analysed. Reco was estimated from the measured EC fluxes at night after filtering for adequate turbulence (u* > 1.5). Reco measurements were then binned into 1°C intervals and median values were first fitted using the Locally Estimated Scatterplot Smoothing (LOESS) method (to determine the dominant trend of the experimental curve) Reco shows an exponential increase with air and soil temperature, until SWC measured at 0.2 m depth remains above 19% vol. Secondly, the coefficients of the selected Lloyd and Taylor (1994) were estimated through the nonlinear least square (nls) method: Rref (ecosystem respiration rate at a reference temperature of 10 °C was equal to 1.65 μmol m-2 s-1 and E0 (activation energy parameter that determines the temperature sensitivity) was equal to 322.46. In addition, bare and drier soils show a reduced response of measured CO2 efflux to increasing

  12. Medclic: the Mediterranean in one click

    NASA Astrophysics Data System (ADS)

    Troupin, Charles; Frontera, Biel; Sebastián, Kristian; Pau Beltran, Joan; Krietemeyer, Andreas; Gómara, Sonia; Gomila, Mikel; Escudier, Romain; Juza, Mélanie; Mourre, Baptiste; Garau, Angels; Cañellas, Tomeu; Tintoré, Joaquín

    2016-04-01

    "Medclic: the Mediterranean in one click" is a research and dissemination project focused on the scientific, technological and societal approaches of the Balearic Islands Coastal Observing and Forecasting System ({SOCIB}{www.socib.es}) in a collaboration with "la Caixa" Foundation. SOCIB aims at research excellence and the development of technology which enables progress toward the sustainable management of coastal and marine environments, providing solutions to meet the needs of society. Medclic goes one step forward and has two main goals: at the scientific level, to advance in establishing and understanding the mesoscale variability at the regional scale and its interaction, and thus improving the characterisation of the "oceanic weather" in the Mediterranean; at the outreach level: to bring SOCIB and the new paradigm of multi-platform observation in real time closer to society, through scientific outreach. SOCIB Data Centre is the core of the new multi-platform and real time oceanography and is responsible for directing the different stages of data management, ranging from data acquisition to its distribution and visualization through web applications. The system implemented relies on open source solutions and provides data in line with international standards and conventions (INSPIRE, netCDF Climate and Forecast, ldots). In addition, the Data Centre has implemented a REST web service, called Data Discovery. This service allows data generated by SOCIB to be integrated into applications developed by the Data Centre itself or by third parties, as it is the case with Medclic. Relying on this data distribution, the new web Medclic, www.medclic.es, constitutes an interactive scientific and educational area of communication that contributes to the rapprochement of the general public with the new marine and coastal observing technologies. Thanks to the Medclic web, data coming from new observing technologies in oceanography are available in real time and in one clic

  13. Environmental Changes in the pre-Messinian Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Mayser, J. P.; Marzocchi, A.; Lunt, D. J.; Pancost, R. D.; Sierro, F. J.; Flecker, R.

    2015-12-01

    The Messinian Salinity Crisis (MSC) is an extreme event which occurred in the Mediterranean Basin at the end of the Miocene (5.97 to 5.33 Ma) resulting in thick evaporite deposits. There is evidence of restriction of the Atlantic-Mediterranean corridor several million years before the first evaporites. These pre-MSC successions are dominated by precession-controlled lithological variations which are putative responses to changing fluvial runoff. Recent climate simulations indicate that runoff into the Eastern Mediterranean is influenced by monsoonal precipitation from the North African continent. The Sorbas Basin in Spain and the Pissouri Section on Cyprus both contain pre-MSC successions from the margins of the Mediterranean Basin. We analysed biomarkers in conjunction with existing faunal records to understand whether simulated runoff changes were manifested in the sedimentological record and organic matter assemblages. This multi-proxy dataset allows us to compare the environmental evolution of the western vs. eastern basins prior to the MSC and allows us to test both climate models for Messinian climate variabitly and conceptual models for sedimentation. In the Sorbas Basin, pronounced orbital changes in faunal assemblages reflect Mediterrannean influences into the local Sorbas system; however, these are not manifested in biomarker assemblages, which are likely governed by more local hydrological processes, which in the Western Mediterranean lacked a strong precessional control. In the Pissouri Basin, however, terrigeous OM inputs sources exhibit strong orbital variations, suggesting a close link to precessionally driven changes in rainfall. Together, these results validate the sapropel formation hypothesis in the Mediterranean and confirm a strong precessional control on the African monsoon during the late Miocene; however, they also reveal the complex controls on the hydrology and sedimentology of marginal Mediterranean basins, such as the Sorbas Basin.

  14. Setting Priorities for Regional Conservation Planning in the Mediterranean Sea

    PubMed Central

    Micheli, Fiorenza; Levin, Noam; Giakoumi, Sylvaine; Katsanevakis, Stelios; Abdulla, Ameer; Coll, Marta; Fraschetti, Simonetta; Kark, Salit; Koutsoubas, Drosos; Mackelworth, Peter; Maiorano, Luigi; Possingham, Hugh P.

    2013-01-01

    Spatial prioritization in conservation is required to direct limited resources to where actions are most urgently needed and most likely to produce effective conservation outcomes. In an effort to advance the protection of a highly threatened hotspot of marine biodiversity, the Mediterranean Sea, multiple spatial conservation plans have been developed in recent years. Here, we review and integrate these different plans with the goal of identifying priority conservation areas that represent the current consensus among the different initiatives. A review of six existing and twelve proposed conservation initiatives highlights gaps in conservation and management planning, particularly within the southern and eastern regions of the Mediterranean and for offshore and deep sea habitats. The eighteen initiatives vary substantially in their extent (covering 0.1–58.5% of the Mediterranean Sea) and in the location of additional proposed conservation and management areas. Differences in the criteria, approaches and data used explain such variation. Despite the diversity among proposals, our analyses identified ten areas, encompassing 10% of the Mediterranean Sea, that are consistently identified among the existing proposals, with an additional 10% selected by at least five proposals. These areas represent top priorities for immediate conservation action. Despite the plethora of initiatives, major challenges face Mediterranean biodiversity and conservation. These include the need for spatial prioritization within a comprehensive framework for regional conservation planning, the acquisition of additional information from data-poor areas, species or habitats, and addressing the challenges of establishing transboundary governance and collaboration in socially, culturally and politically complex conditions. Collective prioritised action, not new conservation plans, is needed for the north, western, and high seas of the Mediterranean, while developing initial information

  15. Architectural plasticity in a Mediterranean winter annual

    PubMed Central

    Shemesh, Hagai; Zaitchik, Benjamin; Acuña, Tania; Novoplansky, Ariel

    2012-01-01

    Size variability in plants may be underlain by overlooked components of architectural plasticity. In annual plants, organ sizes are expected to depend on the availability and reliability of resources and developmental time. Given sufficient resources and developmental time, plants are expected to develop a greater number of large branches, which would maximize fitness in the long run. However, under restrictive growth conditions and environmental reliability, developing large branches might be risky and smaller branches are expected to foster higher final fitness. Growth and architecture of Trifolium purpureum (Papilionaceae) plants from both Mediterranean (MED) and semi-arid (SAR) origins were studied, when plants were subjected to variable water availability, photoperiod cues and germination timing. Although no clear architectural plasticity could be found in response to water availability, plants subjected to photoperiod cuing typical to late spring developed fewer basal branches. Furthermore, plants that germinated late were significantly smaller, with fewer basal branches, compared with plants which grew for the same time, starting at the beginning of the growing season. The results demonstrate an intricate interplay between size and architectural plasticities, whereby size modifications are readily induced by environmental factors related to prevalent resource availability but architectural plasticity is only elicited following the perception of reliable anticipatory cues. PMID:22499177

  16. Potential vorticity patterns in Mediterranean hurricanes

    NASA Astrophysics Data System (ADS)

    Laviola, Sante; Marcello Miglietta, M.; Cerrai, Diego; Cattani, Elsa; Levizzani, Vincenzo

    2016-04-01

    Two new variables have been introduced to better identify the potential vorticity (PV) anomalies due to the intrusion of dry stratospheric air from those induced by the diabatic latent heating. This new approach has been applied to the analysis of three Mediterranean tropical-like cyclones characterized by heavy precipitation patterns. Model simulations show that the interaction between an upper level PV streamer, located on the left exit of a jet stream and a middle-low level PV anomaly, induced by the convection development around the low level vortex, plays a key role in the intensification of cyclones in all cases. These anomalies, despite their strong mutual interaction, do not form a fully developed PV tower. In the mature stage, the shape of the upper level PV anomaly around the cyclone is different for each case and appears somehow dependent on the lifetime of the vortex. A first comparison with satellite-derived products seems to confirm the initial results from model simulations.

  17. Lightning activity and aerosols over the Mediterranean

    NASA Astrophysics Data System (ADS)

    Proestakis, Emmanouil; Kazadzis, Stelios; Kotroni, Vassiliki; Lagouvardos, Kostas; Kazantzidis, Andreas

    2015-04-01

    Lightning activity has received extended scientific attention over the past decades. Several international studies on lightning activity and initiation mechanisms have related the increased aerosol concentrations to lightning enhancement. In the frame of TALOS project, we investigated the effect of aerosols on lightning activity over the Mediterranean Sea. Cloud to ground lightning activity data from ZEUS lightning detection network operated and maintained by the National Observatory of Athens, were used along with atmospheric optical depth (AOD) data retrieved by MODIS, on board Aqua satellite. The analysis covers a period of nine years, spanning from 2005 up to 2013. The results show the importance of aerosols in lightning initiation and enhancement. It is shown that the mean AOD of the days with lightning activity per season is larger than the mean seasonal AOD in 90% of the under study domain. Furthermore, lightning activity increase with increasing aerosol loading was found to be more pronounced during summertime and for atmospheric optical depth values up to 0.4. Additionally, during summertime, the spatial analysis showed that the percentage of days with lightning activity is increasing with increasing aerosol loading. Finally, time series for the period 2005-2013 of the days with lightning activity and AOD differences showed similar temporal behavior. Overall, both the spatial and temporal analysis showed that lightning activity is correlated to aerosol loading and that this characteristic is consistent for all seasons.

  18. Index medicus for the Eastern Mediterranean region

    PubMed Central

    Al-Shorbaji, Najeeb

    2008-01-01

    The study provides the rationale, history and current status of the Index Medicus for the World Health Organization Eastern Mediterranean Region. The Index is unique in combining the geographic coverage of peer-reviewed health and biomedical journals (408 titles) from the 22 countries of the Region. Compiling and publishing the Index coupled with a document delivery service is an integral part of the WHO Regional Office's knowledge management and sharing programme. In this paper, bibliometric indicators are presented to demonstrate the distribution of journals, articles, languages, subjects and authors as well as availability in printed and electronic formats. Two countries in the Region (Egypt and Pakistan) contribute over 50% of the articles in the Index. About 90% of the articles are published in English. Epidemiology articles represent 8% of the entire Index. 15% of the journals in the Index are also indexed in MEDLINE, while 7% are indexed in EMBASE. Future developments of the Index will include covering more journals and adding other types of health and biomedical literature, including reports, theses, books and current research. The challenges and lessons learnt are discussed. PMID:18826568

  19. Lightning flash multiplicity in eastern Mediterranean thunderstorms

    NASA Astrophysics Data System (ADS)

    Yair, Y.; Shalev, S.; Erlich, Z.; Agrachov, A.; Katz, E.; Saaroni, H.; Price, C.; Ziv, B.

    2014-02-01

    Cloud-to-ground lightning flashes usually consist of one or several strokes coming in very short temporal succession and close spatial proximity. A commonly used method for converting stroke data into flashes is using the National Lightning Detection Network (NLDN) thresholds of maximum temporal separation of 0.5 s and maximum lateral distance of 10 km radius between successive strokes. In the present study, we tested a location-based algorithm with several spatial and temporal ranges, and analyzed stroke data obtained by the Israel Lightning Location System (ILLS) during one year (1.8.2009-31.7.2010). We computed the multiplicity, the percentage of single stroke flashes and the geographical distribution of average multiplicity values for thunderstorms in the Eastern Mediterranean region. Results show that for the NLDN thresholds, the percentage of single stroke flashes in Israel was 37% and the average multiplicity was 1.7. We reanalyzed the data with a spatial range that equals twice the ILLS location error and shorter times. For the new thresholds of maximum distance of 2.5 km and maximum allowed temporal separation of 0.2 s we find that the mean multiplicity of negative CGs is lowered to 1.4 and find a percentage of 58% of single stroke flashes. A unique severe storm from 30 October 2009 is analyzed and compared with the annual average of 2009/2010, showing that large deviations from the mean values can occur in specific events.

  20. The Mediterranean diet: health, science and society.

    PubMed

    Gerber, Mariette; Hoffman, Richard

    2015-04-01

    The Mediterranean diet (MD) emerged as a healthy food regimen long before it could be recognised which nutrients or foods were responsible for its observed benefits, and it was only in the middle of the last century that the first scientific approach 'The Seven Countries Study' appeared. Epidemiological and anthropological studies of the MD converged, first by investigating at single nutrients or foods, then by adopting the more holistic approach of dietary patterns (DP), and now with a molecular approach. These studies resulted in convincing evidence that a MD decreases the risk of all-cause mortality and cardiovascular mortality and incidence. A risk reduction of developing type 2 diabetes is probable. Evidence is less stringent for other metabolic diseases and all cancers but from possible to probable for some cancer sites. Although DP showed that the MD has to be considered in its totality, olive oil could have a specific role. Lifestyle factors such as physical activity for energy balance, outdoor life for vitamin D synthesis and conviviality are also probably partly responsible for the health benefits. The MD is a lifestyle well suited for coping not only with personal health but also with wider societal concerns in relation to environment, public health and economy.

  1. Mediterranean Diet and Cardiodiabesity: A Review

    PubMed Central

    García-Fernández, Elena; Rico-Cabanas, Laura; Rosgaard, Nanna; Estruch, Ramón; Bach-Faig, Anna

    2014-01-01

    Cardiodiabesity has been used to define and describe the well-known relationship between type 2 Diabetes Mellitus (T2DM), obesity, the metabolic syndrome (MetS) and cardiovascular disease (CVD). The objective of this study was to perform a scientific literature review with a systematic search to examine all the cardiovascular risk factors combined and their relationship with adherence to the Mediterranean Diet (MedDiet) pattern as primary prevention against cardiodiabesity in a holistic approach. Research was conducted using the PubMed database including clinical trials, cross-sectional and prospective cohort studies. Thirty-seven studies were reviewed: fourteen related to obesity, ten to CVD, nine to MetS, and four to T2DM. Indeed 33 provided strong evidence on the association between adherence to a MedDiet and a reduced incidence of collective cardiodiabesity risk in epidemiological studies. This scientific evidence makes the MedDiet pattern very useful for preventive strategies directed at the general population and also highlights the need to consider all these diet-related risk factors and health outcomes together in daily primary care. PMID:25192027

  2. Mediterranean spotted fever in southeastern Romania.

    PubMed

    Pitigoi, Daniela; Olaru, Ioana D; Badescu, Daniela; Rafila, Alexandru; Arama, Victoria; Hristea, Adriana

    2013-01-01

    Although cases of Mediterranean spotted fever (MSF) have been reported for decades in southeastern Romania, there are few published data. We retrospectively studied 339 patients, diagnosed with MSF at the National Institute of Infectious Diseases "Prof. Dr. Matei Bals" between 2000 and 2011, in order to raise awareness about MSF in certain regions of Romania. According to the Raoult diagnostic criteria 171 (50.4%) had a score >25 points. Mean age was 52.5 years. One hundred and fifty-five (90.6%) patients were from Bucharest and the surrounding region. Almost all patients presented with fever (99.4%) and rash (98.2%), and 57.9% had evidence of a tick bite. There were no recorded deaths. Serologic diagnosis was made by indirect immunofluorescence assay. Of the 171 patients, serology results for R. conorii were available in 147. One hundred and twenty-three (83.7%) of them had a titer IgG ≥1:160 or a fourfold increase in titer in paired samples. MSF is endemic in southeastern Romania and should be considered in patients with fever and rash even in the absence of recognized tick exposure. Since the disease is prevalent in areas highly frequented by tourists, travel-associated MSF should be suspected in patients with characteristic symptoms returning from the endemic area.

  3. Recent nutrient dynamics in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Lee, Kitack; Moon, Ji-Young

    2016-04-01

    The concentrations of nitrate (N) and phosphate (P), and the N:P ratio in the upper water column of the Mediterranean Sea (MED) were examined using observational data (~173,000 data points) collected since 1980s. The observed trends were found to distinctly evolve in the western and eastern MED. In the western MED the N and P concentrations have rapidly increased over time and was broadly consistent with the riverine input history from the populated areas surrounding the western MED. Contrarily, the N and P concentrations in the eastern MED markedly increased up until the mid-1995 and briefly remained high between 1995 and 2000. The N concentration rapidly decreased thereafter. In particular, the three-phase temporal transition of N and P in the eastern MED (increase-constant-decline) was more consistent with the emission history of pollutant nitrogen from the western European continent, in which regulation of emissions of pollutant nitrogen has been in place since 1970s. Our analysis implies that the recent N dynamics in the upper MED appeared to be sensitive to input dynamics of anthropogenic N, via atmospheric deposition and river. This conclusion is further strengthened by good agreement between the integrated rate of increase in the upper-water N inventory and the total anthropogenic N input during the past 30 years.

  4. Study of the impact of cyclogenesis at the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Ribo, M.; Llasat, C.

    2009-09-01

    The Mediterranean Basin is usually affected by high impact weather events, generating high impacts in all Mediterranean countries and causing important damages. This basin is surrounded by mountains and arid regions, and the interaction of the air flow with the orography barriers produces many effects, the most important is the formation of low pressure centers. This is one of the reasons why the Mediterranean Sea is considered to be the most cyclogenetic area in the world (Jansà, 1997). Floods are also one of the most important natural hazards in the Mediterranean Basin. Flood events occur when soil absorption, runoff or drainage cannot adequately disperse intense rainfall from quasi-stationary or stationary weather systems in short time periods. In some occasions these floods produce high social impact in the affected areas. Our work presents the study of the relationship between the flood episodes and the presence of cyclones in the Mediterranean Basin during those episodes, between 1990 and 2004. Information about social impact of each event has also been considered. To do these analyses the MEDEX database (MEDiterranean EXperiment on cyclones that produce high impact weather in the Mediterranean) has been improved in the frame work of the European FLASH project, and information about cyclones and rainfall has been extracted from the MEDEX cyclones database. A total of 217 flood events had been identified. Once the presence of one or more cyclones during each flood episode has been identified, temporal and regional analyses were made to determine the distribution of the cyclonic centers and to study the evolution of the events. Mediterranean cyclogenesis is leaded by influence of external systems (along the African coast, from the Atlantic Ocean, and from the west of Europe), although the majority of the cyclones (87% of the studied cases) are generated in the Mediterranean Basin, under influence of preexistent systems. There are different Mediterranean

  5. Soil erosion in a man-made landscape: the Mediterranean

    NASA Astrophysics Data System (ADS)

    Cerdà, A.; Ruiz Sinoga, J. D.; Cammeraat, L. H.

    2012-04-01

    Mediterranean-type ecosystems are characterised by a seasonally contrasted distribution of precipitation, by the coincidence of the driest and hottest season in summer, by an often-mountainous terrain, and by a long history of intense human occupation, especially around the Mediterranean Sea. The history of the Mediterranean lands is the history of human impacts on the soil system, and soil erosion is the most intense and widespread impact on this land where high intensity and uneven rainfall is found. A review of the soil erosion rates measured in the Mediterranean basin will be shown. The measurements done by means of erosion pins, topographical measurements, rainfall simulators, Gerlach collectors in open or close plots, watershed/basin measurements, reservoirs siltation and historical data will be shown. A review of the soil erosion models applied in the Mediterranean will be shown. The tentative approach done until October 2011 show that the soil erosion rates on Mediterranean type ecosystems are not as high as was supposed by the pioneers in the 70's. And this is probably due to the fact that the soils are very shallow and sediments are not available after millennia of high erosion rates. This is related to the large amount of rock fragments are covering the soil, and the rock outcrops that are found in the upper slope trams and the summits. Soil erosion in the Mediterranean is seasonal due to the rainfall concentration in winter, and highly variable within years as the high intensity rainfall events control the sediment production. Natural vegetation is adapted to the Mediterranean environmental conditions, and they are efficient to control the soil losses. An example are the forest fire that increase the soil losses but this is a temporal change as after 2-4 years the soil erosion rates are similar to the pre-fire period. Agriculture lands are the source of sediments although the highest erosion rates are found in badland areas that cover a small part of

  6. Ozone and carbon monoxide budgets over the Eastern Mediterranean.

    PubMed

    Myriokefalitakis, S; Daskalakis, N; Fanourgakis, G S; Voulgarakis, A; Krol, M C; Aan de Brugh, J M J; Kanakidou, M

    2016-09-01

    The importance of the long-range transport (LRT) on O3 and CO budgets over the Eastern Mediterranean has been investigated using the state-of-the-art 3-dimensional global chemistry-transport model TM4-ECPL. A 3-D budget analysis has been performed separating the Eastern from the Western basins and the boundary layer (BL) from the free troposphere (FT). The FT of the Eastern Mediterranean is shown to be a strong receptor of polluted air masses from the Western Mediterranean, and the most important source of polluted air masses for the Eastern Mediterranean BL, with about 40% of O3 and of CO in the BL to be transported from the FT aloft. Regional anthropogenic sources are found to have relatively small impact on regional air quality in the area, contributing by about 8% and 18% to surface levels of O3 and CO, respectively. Projections using anthropogenic emissions for the year 2050 but neglecting climate change calculate a surface O3 decrease of about 11% together with a surface CO increase of roughly 10% in the Eastern Mediterranean. PMID:27135565

  7. Ozone and carbon monoxide budgets over the Eastern Mediterranean.

    PubMed

    Myriokefalitakis, S; Daskalakis, N; Fanourgakis, G S; Voulgarakis, A; Krol, M C; Aan de Brugh, J M J; Kanakidou, M

    2016-09-01

    The importance of the long-range transport (LRT) on O3 and CO budgets over the Eastern Mediterranean has been investigated using the state-of-the-art 3-dimensional global chemistry-transport model TM4-ECPL. A 3-D budget analysis has been performed separating the Eastern from the Western basins and the boundary layer (BL) from the free troposphere (FT). The FT of the Eastern Mediterranean is shown to be a strong receptor of polluted air masses from the Western Mediterranean, and the most important source of polluted air masses for the Eastern Mediterranean BL, with about 40% of O3 and of CO in the BL to be transported from the FT aloft. Regional anthropogenic sources are found to have relatively small impact on regional air quality in the area, contributing by about 8% and 18% to surface levels of O3 and CO, respectively. Projections using anthropogenic emissions for the year 2050 but neglecting climate change calculate a surface O3 decrease of about 11% together with a surface CO increase of roughly 10% in the Eastern Mediterranean.

  8. Little Ice Age glaciers in the Mediterranean mountains

    NASA Astrophysics Data System (ADS)

    Hughes, Philip

    2014-05-01

    Only a few small glaciers survive today in the Mountains of the Mediterranean. Notable examples are found in the Pyrenees, Maritime Alps, Italian Apennines, the Dinaric and Albanian Alps and the mountains of Turkey. Many glaciers disappeared during the 20th Century. Glaciers were much larger and more numerous during the Little Ice Age (Hughes, 2014). Small glaciers even existed as far south as the High Atlas of Morocco and the Sierra Nevada of southern Spain. In more northerly areas, such as the western Balkans, glaciers and permanent snow patches occupied hundreds of cirques on relatively low-lying mountains. In the High Atlas and the Sierra Nevada no glaciers exist today, whilst in the Balkans only a few modern glaciers have been reported. A similar situation is apparent throughout the mountains of the Mediterranean region. New evidence for glacier change since the Little Ice Age will be published soon in Hughes (2014) and this paper reviews the extent, timing and climatic significance of Little Ice Age glaciation in the Mediterranean region. Reference: Hughes, P.D. (2014) Little Ice Age glaciers in the Mediterranean mountains. In: Carozza, J.-M., Devillers, B., Morhange, C. (eds) Little Ice Age in the Mediterranean, Méditerranée, volume 123.

  9. Gathered Mediterranean food plants--ethnobotanical investigations and historical development.

    PubMed

    Rivera, Diego; Obón, Concepción; Heinrich, Michael; Inocencio, Cristina; Verde, Alonso; Fajardo, José

    2006-01-01

    The diversity of local Mediterranean food elements is not known in detail, but offers itself to search for new vegetables, salads, fruits and spices which could be used in to enrich diets outside their region of origin. Most amid those interesting local elements are edible wild plants and weeds. Ethnobotanical research has identified ca. 2,300 different plant and fungi taxa, which are gathered and consumed in the Mediterranean. Among these, >1,000 are only consumed in one single zone, therefore are strictly local. The percentage of local gathered food plant (GFP) taxa (present in <5 samples), is higher in the main centers of diversity at the periphery of the Mediterranean (Sahara, Alps, Caucasus, Canary Islands, the Levant). Islands (Sicily, Sardinia, Crete, Cyprus) also show a high proportion. Endemism of GFP taxa only accounts for a limited number of these 'ethnobotanical endemics' (only ca. 350 are endemic/ endangered species). On the other hand, only a few taxa--30 occurring in >20 samples--are consumed in most of the Mediterranean. Most have been analyzed in the Local Food- Nutraceuticals project. The ca. 800 GFP taxa that occur in more than the 5% of localities show a geographical pattern that permits one to recognize seven geographical groups. These groups show relationships with types of Mediterranean diet and could also be related with human genetic polymorphism through long-term co-evolution in a geographical mosaic pattern.

  10. Evaluation of Rainfall-Runoff Models for Mediterranean Subcatchments

    NASA Astrophysics Data System (ADS)

    Cilek, A.; Berberoglu, S.; Donmez, C.

    2016-06-01

    The development and the application of rainfall-runoff models have been a corner-stone of hydrological research for many decades. The amount of rainfall and its intensity and variability control the generation of runoff and the erosional processes operating at different scales. These interactions can be greatly variable in Mediterranean catchments with marked hydrological fluctuations. The aim of the study was to evaluate the performance of rainfall-runoff model, for rainfall-runoff simulation in a Mediterranean subcatchment. The Pan-European Soil Erosion Risk Assessment (PESERA), a simplified hydrological process-based approach, was used in this study to combine hydrological surface runoff factors. In total 128 input layers derived from data set includes; climate, topography, land use, crop type, planting date, and soil characteristics, are required to run the model. Initial ground cover was estimated from the Landsat ETM data provided by ESA. This hydrological model was evaluated in terms of their performance in Goksu River Watershed, Turkey. It is located at the Central Eastern Mediterranean Basin of Turkey. The area is approximately 2000 km2. The landscape is dominated by bare ground, agricultural and forests. The average annual rainfall is 636.4mm. This study has a significant importance to evaluate different model performances in a complex Mediterranean basin. The results provided comprehensive insight including advantages and limitations of modelling approaches in the Mediterranean environment.

  11. A Preliminary Analysis of Disturbance Tracksover the Mediterranean Basin

    NASA Astrophysics Data System (ADS)

    Karas, S.; Zangvil, A.

    The Mediterranean basin experiences considerable cyclone activity mostly during fall, winter and spring and diminished activity during summer. In this study we present results of synoptic disturbance track analysis for two contrasting winter months and two, near average, summer months over the eastern Mediterranean. The surface and 500hPa disturbance tracks were subjectively analyzed from two points of view. First, looking at tracks of conventionally defined cyclone centers (eddies) based on actual pressure and height distribution and second, looking at tracks of transient cyclonic disturbances (TRADs), defined as centers of negative deviations from the time mean. The second type of analysis demonstrated a considerable increase in the number of detectable tracks. Over the Mediterranean and vicinity the ratio between the number of surface TRAD tracks to cyclone tracks is, about 2, whereas at 500hPa the ratio is much higher, about 5. However, the average life span of transient disturbances was only slightly longer than that of conventional cyclones (mainly at 500hPa). At the surface and at 500hPa about 50% of the cyclone tracks coincided to a certain extent with TRAD tracks. In summer, when conventional analysis over the eastern Mediterranean yields mostly quasi-stationary low pressure centers associated with the Persian Gulf Trough, we detected clear signs of transient disturbances. Some interpretations of the differences between cyclones and TRADs in terms of weather in the eastern Mediterranean are also made.

  12. Clastic depositional styles and reservoir potential of Mediterranean basins

    SciTech Connect

    Bouma, A.H. )

    1990-05-01

    A variety of tectonic styles and activities throughout the late Mesozoic and younger epochs influenced sediment transport to the Mediterranean basins and, consequently, the approach needed to finding reservoir-type clastics. The style of the present-day basins varies from west to east, with large basinal depressions and continental rises in the western province, more elongate shapes in the central area, and numerous small basins and trenches in the eastern Mediterranean. In general terms, all these basins contain a similar fill: a deep-water sequence older than late Miocene, overlain by upper Miocene evaporites, and topped by Pliocene-Quaternary clastics. The exact type of fill depends on several factors, including proximity to the sediment source, climatic conditions, subsidence and tectonic activity, and tectono-eustatic or glacio-eustatic oscillations. Investigations on many of the clastic reservoirs in Mediterranean basins should emphasize submarine fans. The modern Mediterranean Sea contains several mid-sized fans (Rhone, Ebro, Valencia, and Nile fans) and many small ones (e.g., Crati Fan). There are several well-studied Tertiary subsurface and outcropping turbidite systems. The concept of deep-water marine sands, and many of the initial studies, began with some of the now classic outcrops in Italy, France, and Spain. A well-integrated study of both modern and ancient turbidite series is needed to construct basic exploration models for the Mediterranean region. 9 figs., 1 tab.

  13. Mediterranean circulation perturbations over the last five centuries: Relevance to past Eastern Mediterranean Transient-type events.

    PubMed

    Incarbona, Alessandro; Martrat, Belen; Mortyn, P Graham; Sprovieri, Mario; Ziveri, Patrizia; Gogou, Alexandra; Jordà, Gabriel; Xoplaki, Elena; Luterbacher, Juerg; Langone, Leonardo; Marino, Gianluca; Rodríguez-Sanz, Laura; Triantaphyllou, Maria; Di Stefano, Enrico; Grimalt, Joan O; Tranchida, Giorgio; Sprovieri, Rodolfo; Mazzola, Salvatore

    2016-07-14

    The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales.

  14. Mediterranean circulation perturbations over the last five centuries: Relevance to past Eastern Mediterranean Transient-type events

    NASA Astrophysics Data System (ADS)

    Incarbona, Alessandro; Martrat, Belen; Mortyn, P. Graham; Sprovieri, Mario; Ziveri, Patrizia; Gogou, Alexandra; Jordà, Gabriel; Xoplaki, Elena; Luterbacher, Juerg; Langone, Leonardo; Marino, Gianluca; Rodríguez-Sanz, Laura; Triantaphyllou, Maria; di Stefano, Enrico; Grimalt, Joan O.; Tranchida, Giorgio; Sprovieri, Rodolfo; Mazzola, Salvatore

    2016-07-01

    The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales.

  15. Mediterranean circulation perturbations over the last five centuries: Relevance to past Eastern Mediterranean Transient-type events

    PubMed Central

    Incarbona, Alessandro; Martrat, Belen; Mortyn, P. Graham; Sprovieri, Mario; Ziveri, Patrizia; Gogou, Alexandra; Jordà, Gabriel; Xoplaki, Elena; Luterbacher, Juerg; Langone, Leonardo; Marino, Gianluca; Rodríguez-Sanz, Laura; Triantaphyllou, Maria; Di Stefano, Enrico; Grimalt, Joan O.; Tranchida, Giorgio; Sprovieri, Rodolfo; Mazzola, Salvatore

    2016-01-01

    The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales. PMID:27412622

  16. Mediterranean circulation perturbations over the last five centuries: Relevance to past Eastern Mediterranean Transient-type events.

    PubMed

    Incarbona, Alessandro; Martrat, Belen; Mortyn, P Graham; Sprovieri, Mario; Ziveri, Patrizia; Gogou, Alexandra; Jordà, Gabriel; Xoplaki, Elena; Luterbacher, Juerg; Langone, Leonardo; Marino, Gianluca; Rodríguez-Sanz, Laura; Triantaphyllou, Maria; Di Stefano, Enrico; Grimalt, Joan O; Tranchida, Giorgio; Sprovieri, Rodolfo; Mazzola, Salvatore

    2016-01-01

    The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910 ± 12, 1812 ± 18, 1725 ± 25 and 1580 ± 30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales. PMID:27412622

  17. Diversity of magnetotactic bacteria from a French pristine Mediterranean area.

    PubMed

    Fuduche, Maxime; Postec, Anne; Davidson, Sylvain; Chauvin, Jean-Paul; Galès, Grégoire; Hirschler-Réa, Agnès; Ollivier, Bernard; Wu, Long-Fei; Pradel, Nathalie

    2015-04-01

    Magnetotactic bacteria synthesize intracellular magnetite and/or greigite magnetosome crystals. They play a significant role in both iron and sulfur cycles in sedimentary aquatic environments. To get insight into the bio-geochemical contribution of MTB, more studies concerning their ecology and their distribution in diverse habitats are necessary. The MTB community of an oil-industry polluted area of the French Mediterranean coast has been previously investigated. Here, we investigate the MTB community from coastal sediments of a Mediterranean pristine area using optical and transmission electron microscopy and phylogenetic analysis based on 16S rRNA gene sequences. A particularly high diversity of MTB was observed, with cocci phylogenetically distributed across the order Magnetococcales, including a novel cluster with sequences from the Mediterranean Sea designated as "Med group", and novel morphotypes. PMID:25487117

  18. Persistent toxic substances in Mediterranean aquatic species.

    PubMed

    Miniero, Roberto; Abate, Vittorio; Brambilla, Gianfranco; Davoli, Enrico; De Felip, Elena; De Filippis, Stefania P; Dellatte, Elena; De Luca, Silvia; Fanelli, Roberto; Fattore, Elena; Ferri, Fabiola; Fochi, Igor; Rita Fulgenzi, Anna; Iacovella, Nicola; Iamiceli, Anna Laura; Lucchetti, Dario; Melotti, Paolo; Moret, Ivo; Piazza, Rossano; Roncarati, Alessandra; Ubaldi, Alessandro; Zambon, Stefano; di Domenico, Alessandro

    2014-10-01

    Fish and fishery products may represent one of the main sources of dietary exposure to persistent toxic substances (PTSs) such as polychlorinated dibenzodioxins, dibenzofurans, and biphenyls; polybromodiphenyl ethers; organochlorine pesticides; perfluorooctanoic acid and perfluorooctane sulfonate; and inorganic mercury and methyl mercury. In this study, PTS contamination of Mediterranean fish and crustaceans caught in Italian coastal waters was investigated in order to increase the representativeness of the occurrence database for wild species. The objectives were to verify the suitability of regulatory limits for PTSs, identify background concentrations values, if any, and examine the possible sources of variability when assessing the chemical body burdens of aquatic species. Twelve wild species of commercial interest and two farmed fish species were chosen. Excluding methyl mercury, chemical concentrations found in wild species fell generally towards the low ends of the concentration ranges found in Europe according to EFSA database and were quite lower than the tolerable maximum levels established in the European Union; farmed fish always showed contamination levels quite lower than those detected in wild species. The data obtained for wild species seemed to confirm the absence of local sources of contamination in the chosen sampling areas; however, species contamination could exceed regulatory levels even in the absence of specific local sources of contamination as a result of the position in the food web and natural variability in species' lifestyle. A species-specific approach to the management of contamination in aquatic organisms is therefore suggested as an alternative to a general approach based only on contaminant body burden. A chemical-specific analysis performed according to organism position in the food chain strengthened the need to develop this approach. PMID:25020099

  19. Persistent toxic substances in Mediterranean aquatic species.

    PubMed

    Miniero, Roberto; Abate, Vittorio; Brambilla, Gianfranco; Davoli, Enrico; De Felip, Elena; De Filippis, Stefania P; Dellatte, Elena; De Luca, Silvia; Fanelli, Roberto; Fattore, Elena; Ferri, Fabiola; Fochi, Igor; Rita Fulgenzi, Anna; Iacovella, Nicola; Iamiceli, Anna Laura; Lucchetti, Dario; Melotti, Paolo; Moret, Ivo; Piazza, Rossano; Roncarati, Alessandra; Ubaldi, Alessandro; Zambon, Stefano; di Domenico, Alessandro

    2014-10-01

    Fish and fishery products may represent one of the main sources of dietary exposure to persistent toxic substances (PTSs) such as polychlorinated dibenzodioxins, dibenzofurans, and biphenyls; polybromodiphenyl ethers; organochlorine pesticides; perfluorooctanoic acid and perfluorooctane sulfonate; and inorganic mercury and methyl mercury. In this study, PTS contamination of Mediterranean fish and crustaceans caught in Italian coastal waters was investigated in order to increase the representativeness of the occurrence database for wild species. The objectives were to verify the suitability of regulatory limits for PTSs, identify background concentrations values, if any, and examine the possible sources of variability when assessing the chemical body burdens of aquatic species. Twelve wild species of commercial interest and two farmed fish species were chosen. Excluding methyl mercury, chemical concentrations found in wild species fell generally towards the low ends of the concentration ranges found in Europe according to EFSA database and were quite lower than the tolerable maximum levels established in the European Union; farmed fish always showed contamination levels quite lower than those detected in wild species. The data obtained for wild species seemed to confirm the absence of local sources of contamination in the chosen sampling areas; however, species contamination could exceed regulatory levels even in the absence of specific local sources of contamination as a result of the position in the food web and natural variability in species' lifestyle. A species-specific approach to the management of contamination in aquatic organisms is therefore suggested as an alternative to a general approach based only on contaminant body burden. A chemical-specific analysis performed according to organism position in the food chain strengthened the need to develop this approach.

  20. Sea Level Variability in the Mediterranean

    NASA Astrophysics Data System (ADS)

    Zerbini, S.; Bruni, S.; del Conte, S.; Errico, M.; Petracca, F.; Prati, C.; Raicich, F.; Santi, E.

    2015-12-01

    Tide gauges measure local sea-level relative to a benchmark on land, therefore the interpretation of these measurements can be limited by the lack of appropriate knowledge of vertical crustal motions. The oldest sea-level records date back to the 18th century; these observations are the only centuries-old data source enabling the estimate of historical sea-level trends/variations. In general, tide gauge benchmarks were not frequently levelled, except in those stations where natural and/or anthropogenic subsidence was a major concern. However, in most cases, it is difficult to retrieve the historical geodetic levelling data. Space geodetic techniques, such as GNSS, Doris and InSAR are now providing measurements on a time and space-continuous basis, giving rise to a large amount of different data sets. The vertical motions resulting from the various analyses need to be compared and best exploited for achieving reliable estimates of sea level variations. In the Mediterranean area, there are a few centennial tide gauge records; our study focuses, in particular, on the Italian time series of Genoa, Marina di Ravenna, Venice and Trieste. Two of these stations, Marina di Ravenna and Venice, are affected by both natural and anthropogenic subsidence, the latter was particularly intense during a few decades of the 20th century because of ground fluids withdrawal. We have retrieved levelling data of benchmarks at and/or close to the tide gauges from the end of 1800 and, for the last couple of decades, also GPS and InSAR height time series in close proximity of the stations. By using an ensemble of these data, modelling of the long-period non-linear behavior of subsidence was successfully accomplished. After removal of the land vertical motions, the linear long period sea-level rates of all stations are in excellent agreement. Over the last two decades, the tide gauge rates were also compared with those obtained by satellite radar altimetry data.

  1. Lightning climatology over the eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Galanaki, Elissavet; Lagouvardos, Kostas; Kotroni, Vassiliki; Argyriou, Athanassios

    2015-04-01

    In the frame of TALOS project, the lightning activity for a 10-year period (2005-2014) over the eastern Mediterranean (16-320E, 34-460N) is analysed. The study is based on the use of cloud-to-ground lightning activity data from ZEUS system, a Very-Low-Frequency Lightning detection network operated by the National Observatory of Athens. The spatial and temporal (seasonal and diurnal) variability of the lightning activity is examined. Lightning is modulated by the diurnal cycle of insolation and the underlying topographic features of the region. CG lightning activity is dominant over land and coastal areas during summer and spring, while during the cold period of the year is dominant over the sea and is significantly stronger over the mainland than over the sea. The maximum of the lightning activity is observed in June and mostly in the afternoon. The CG variability is consistent with the global lightning activity observations. The effect of elevation, terrain slope and vegetation on the distribution of the CG flashes is also investigated. The orography and the terrain slope favour the lightning activity. Throughout the year, the potential of producing CG flashes ("lightning yield") over bareground is low while during the warm period of the year, the forested areas have increased "lightning yield". Additional analysis focuses on the links of CG lightning with indices related with the atmospheric instability such as the Convective Available Potential Energy (CAPE). CAPE is known as the driving force for thunderstorm development. The analysis showed that the lightning density increases with increasing values of CAPE.

  2. Environmental History on a Central Mediterranean Island

    NASA Astrophysics Data System (ADS)

    Gambin, Belinda; Medail, Frederic; Andrieu-Ponel, Valerie; Djamali, Morteza; Marriner, Nick; Morhange, Christophe; Gambin, Timmy

    2013-04-01

    Through the PaleoMed project a number of cores have been taken from key locations on the Maltese Islands with the aim of establishing various aspects related to the archipelago's historical environment. A multi-disciplinary team have been investigating a number of bodies of evidence including sediments, charcoal and shells. Through this poster I will present the results from pollen samples extracted from a section of one of the cores. The core, taken from Burmarrad, has a section that has been carbon dated to 7200-3200BP. Preliminary results from this site, one of the largest flood plains on Malta, will provide an indication of the local vegetation during this chronological window. Pollen was extracted from sediment deposits following the classical treatment method (eg Moore et al., 1990). Furthermore, identification was undertaken through the use of pollen atlases of Europe and North Africa (Reille, 1992, 1995, 1998) and Beug (2004) along with IMBE's international pollen reference collection. Pollen percentages were calculated in TILIA and the pollen percentage diagram constructed using TGView software (Grimm 2004, 2005). Current results indicate that prior to 7000BP there was a high percentage of aquatic plants, while tree and shrub counts were low. At 6900BP a large increase in Pistacia pollen is recorded, with moderate increase in Plantago (especially lanceolata), Asphodelus, Dinaflagelates and Mirco Foraminifera. At this time there is also a reduction in Cichorioideae & Charcoal in the section. A similar increase in Pistacia at around this time has also been recorded from another core in Burmarrad (Djamali et al., 2012) and in southern Sicily (Tinner et al., 2009). The date of this increase corresponds to the first recorded settlement on the Maltese Islands (circa 5500BC) as well as the climatic optimum of forest cover in the Mediterranean region (Noti et al., 2009).

  3. Fish assemblages of Mediterranean marine caves.

    PubMed

    Bussotti, Simona; Di Franco, Antonio; Francour, Patrice; Guidetti, Paolo

    2015-01-01

    Fish assemblages associated with 14 marine caves and adjacent external rocky reefs were investigated at four Marine Protected Areas (MPAs) along the coasts of Italy. Within the caves sampling was carried out in different sub-habitats: walls, ceilings, bottoms and ends of caves. On the whole, 38 species were recorded inside the 14 caves investigated. Eighteen species were exclusively found inside the caves: they were mainly represented by speleophilic (i.e. species preferentially or exclusively inhabiting caves) gobids (e.g. Didogobius splechtnai) and nocturnal species (e.g. Conger conger). Forty-one species were censused outside, 20 of which were shared with cave habitats. Apogon imberbis was the most common fish found in all 14 caves investigated, followed by Thorogobius ephippiatus (recorded in 13 caves), and Diplodus vulgaris and Scorpaena notata (both censused in 12 caves). Distinct fish assemblages were found between external rocky reefs and the different cave sub-habitats. New data on the distribution of some speleophilic gobids were collected, showing the existence of a pool of species shared by marine caves on a large scale (i.e. hundreds of km). Considering the uniqueness of cave fishes (18 exclusive species and different assemblage structures), the inclusion of marine caves among the habitats routinely investigated for fish biodiversity monitoring could facilitate the achievement of more comprehensive inventories. Due to their contribution to local species diversity and the shelter they provide to species valuable for conservation, marine caves should be prioritized for their inclusion not only within future MPAs through the Mediterranean Sea, but also into larger management spatial planning. PMID:25875504

  4. Fish Assemblages of Mediterranean Marine Caves

    PubMed Central

    Bussotti, Simona; Di Franco, Antonio; Francour, Patrice; Guidetti, Paolo

    2015-01-01

    Fish assemblages associated with 14 marine caves and adjacent external rocky reefs were investigated at four Marine Protected Areas (MPAs) along the coasts of Italy. Within the caves sampling was carried out in different sub-habitats: walls, ceilings, bottoms and ends of caves. On the whole, 38 species were recorded inside the 14 caves investigated. Eighteen species were exclusively found inside the caves: they were mainly represented by speleophilic (i.e. species preferentially or exclusively inhabiting caves) gobids (e.g. Didogobius splechtnai) and nocturnal species (e.g. Conger conger). Forty-one species were censused outside, 20 of which were shared with cave habitats. Apogon imberbis was the most common fish found in all 14 caves investigated, followed by Thorogobius ephippiatus (recorded in 13 caves), and Diplodus vulgaris and Scorpaena notata (both censused in 12 caves). Distinct fish assemblages were found between external rocky reefs and the different cave sub-habitats. New data on the distribution of some speleophilic gobids were collected, showing the existence of a pool of species shared by marine caves on a large scale (i.e. hundreds of km). Considering the uniqueness of cave fishes (18 exclusive species and different assemblage structures), the inclusion of marine caves among the habitats routinely investigated for fish biodiversity monitoring could facilitate the achievement of more comprehensive inventories. Due to their contribution to local species diversity and the shelter they provide to species valuable for conservation, marine caves should be prioritized for their inclusion not only within future MPAs through the Mediterranean Sea, but also into larger management spatial planning. PMID:25875504

  5. Evaluation of TOPLATS on three Mediterranean catchments

    NASA Astrophysics Data System (ADS)

    Loizu, Javier; Álvarez-Mozos, Jesús; Casalí, Javier; Goñi, Mikel

    2016-08-01

    Physically based hydrological models are complex tools that provide a complete description of the different processes occurring on a catchment. The TOPMODEL-based Land-Atmosphere Transfer Scheme (TOPLATS) simulates water and energy balances at different time steps, in both lumped and distributed modes. In order to gain insight on the behavior of TOPLATS and its applicability in different conditions a detailed evaluation needs to be carried out. This study aimed to develop a complete evaluation of TOPLATS including: (1) a detailed review of previous research works using this model; (2) a sensitivity analysis (SA) of the model with two contrasted methods (Morris and Sobol) of different complexity; (3) a 4-step calibration strategy based on a multi-start Powell optimization algorithm; and (4) an analysis of the influence of simulation time step (hourly vs. daily). The model was applied on three catchments of varying size (La Tejeria, Cidacos and Arga), located in Navarre (Northern Spain), and characterized by different levels of Mediterranean climate influence. Both Morris and Sobol methods showed very similar results that identified Brooks-Corey Pore Size distribution Index (B), Bubbling pressure (ψc) and Hydraulic conductivity decay (f) as the three overall most influential parameters in TOPLATS. After calibration and validation, adequate streamflow simulations were obtained in the two wettest catchments, but the driest (Cidacos) gave poor results in validation, due to the large climatic variability between calibration and validation periods. To overcome this issue, an alternative random and discontinuous method of cal/val period selection was implemented, improving model results.

  6. Bed disturbance patterns in two mediterranean impounded rivers

    NASA Astrophysics Data System (ADS)

    Lobera, Gemma; López-Tarazón, José A.; Vericat, Damià; Batalla, Ramon J.; Andrés-Doménech, Ignacio; Millán-Romero, Pedro; Vallés, Francisco

    2015-04-01

    Physical processes in rivers are the result of the interaction between flow regime and hydraulics, morphology, sedimentology and sediment transport. The frequency and magnitude of physical disturbance (i.e. bed stability) control habitat integrity and, consequently, ecological diversity of a particular fluvial system. Mediterranean basins are characterized by marked hydroclimatic fluctuations, from low discharges during long dry seasons to flashy events during wetter periods. Dams alter the river's flow regime (e.g. changes on annual runoff, seasonal patterns, flood magnitude and frequency) and the morphosedimentary dynamics in downstream reaches (e.g. channel incision, bed armouring, vegetation encroachment). Impacts caused by reservoirs in rivers of dryland regions (i.e. Mediterranean) are even more pronounced because their channel form and river ecology are adapted to such highly variable flow regimes. Within this context, this paper analyses intra and inter bed disturbance patterns in two Mediterranean impounded rivers with contrasted characteristics (i.e. high and low Mediterranean character). This research was developed in four river reaches, upstream and downstream of a dam in the Esera and Siurana rivers (Ebro catchment, NE Iberian Peninsula) during two hydrological years. The River Esera is considered a Mediterranean River with a continental character, while the River Siurana has a strong Mediterranean character. As bed disturbance can be assessed in different ways, we have designed a methodological approach that integrates four main components in order to examine the effects of regulation in bed disturbance at different spatial and temporal scales: 1) description of channel morphology (together with changes before and after floods) by means of detailed topographical data and close-range aerial photography; 2) flow discharge and hydraulics by determination of flow parameters from 2D hydraulic modelling that is based on detailed topographical data; 3

  7. Bioremediation of Southern Mediterranean oil polluted sites comes of age.

    PubMed

    Daffonchio, Daniele; Ferrer, Manuel; Mapelli, Francesca; Cherif, Ameur; Lafraya, Alvaro; Malkawi, Hanan I; Yakimov, Michail M; Abdel-Fattah, Yasser R; Blaghen, Mohamed; Golyshin, Peter N; Kalogerakis, Nicolas; Boon, Nico; Magagnini, Mirko; Fava, Fabio

    2013-09-25

    Mediterranean Sea is facing a very high risk of oil pollution due to the high number of oil extractive and refining sites along the basin coasts, and the intense maritime traffic of oil tankers. All the Mediterranean countries have adopted severe regulations for minimizing pollution events and bioremediation feasibility studies for the most urgent polluted sites are undergoing. However, the analysis of the scientific studies applying modern 'meta-omics' technologies that have been performed on marine oil pollution worldwide showed that the Southern Mediterranean side has been neglected by the international research. Most of the studies in the Mediterranean Sea have been done in polluted sites of the Northern side of the basin. Those of the Southern side are poorly studied, despite many of the Southern countries being major oil producers and exporters. The recently EU-funded research project ULIXES has as a major objective to increase the knowledge of the bioremediation potential of sites from the Southern Mediterranean countries. ULIXES is targeting four major polluted sites on the coastlines of Egypt, Jordan, Morocco and Tunisia, including seashore sands, lagoons, and oil refinery polluted sediments. The research is designed to unravel, categorize, catalogue, exploit and manage the diversity and ecology of microorganisms thriving in these polluted sites. Isolation of novel hydrocarbon degrading microbes and a series of state of the art 'meta-omics' technologies are the baseline tools for improving our knowledge on biodegradation capacities mediated by microbes under different environmental settings and for designing novel site-tailored bioremediation approaches. A network of twelve European and Southern Mediterranean partners is cooperating for plugging the existing gap of knowledge for the development of novel bioremediation processes targeting such poorly investigated polluted sites. PMID:23727339

  8. “The Mediterranean Diet, its Components, and Cardiovascular Disease”

    PubMed Central

    Widmer, R. Jay; Flammer, Andreas J.; Lerman, Lilach O.; Lerman, Amir

    2014-01-01

    One of the best studied diets for cardiovascular health is the Mediterranean diet. This consists of fish, monounsaturated fats from olive oil, fruits, vegetables, whole grains, legumes/nuts, and moderate alcohol consumption. The Mediterranean diet has been shown to reduce the burden, or even prevent the development, of cardiovascular disease, breast cancer, depression, colorectal cancer, diabetes, obesity, asthma, erectile dysfunction, and cognitive decline. This diet is also known to improve surrogates of cardiovascular disease, such as waist-to-hip ratio, lipids, and markers of inflammation, as well as primary cardiovascular disease outcomes such as death and events in both observational and randomized controlled trial data. These enhancements easily rival those seen with more established tools used to fight cardiovascular disease such as aspirin, beta-blockers, ACE-inhibitors, and exercise. However, it is unclear if the Mediterranean diet offers cardiovascular disease benefit from its individual constituents or in aggregate. Furthermore, the potential benefit of the Mediterranean diet or its components is not yet validated by concrete cardiovascular disease endpoints in randomized trials or observational studies. This review will focus on the effects of the whole and parts of the Mediterranean diet with regard to both population-based as well as experimental data highlighting cardiovascular disease morbidity or mortality and cardiovascular disease surrogates when hard outcomes are not available. Our synthesis will highlight the potential for the Mediterranean diet to act as a key player in cardiovascular disease prevention, and attempt to identify certain aspects of the diet which are particularly beneficial for cardio-protection. PMID:25447615

  9. Bioremediation of Southern Mediterranean oil polluted sites comes of age.

    PubMed

    Daffonchio, Daniele; Ferrer, Manuel; Mapelli, Francesca; Cherif, Ameur; Lafraya, Alvaro; Malkawi, Hanan I; Yakimov, Michail M; Abdel-Fattah, Yasser R; Blaghen, Mohamed; Golyshin, Peter N; Kalogerakis, Nicolas; Boon, Nico; Magagnini, Mirko; Fava, Fabio

    2013-09-25

    Mediterranean Sea is facing a very high risk of oil pollution due to the high number of oil extractive and refining sites along the basin coasts, and the intense maritime traffic of oil tankers. All the Mediterranean countries have adopted severe regulations for minimizing pollution events and bioremediation feasibility studies for the most urgent polluted sites are undergoing. However, the analysis of the scientific studies applying modern 'meta-omics' technologies that have been performed on marine oil pollution worldwide showed that the Southern Mediterranean side has been neglected by the international research. Most of the studies in the Mediterranean Sea have been done in polluted sites of the Northern side of the basin. Those of the Southern side are poorly studied, despite many of the Southern countries being major oil producers and exporters. The recently EU-funded research project ULIXES has as a major objective to increase the knowledge of the bioremediation potential of sites from the Southern Mediterranean countries. ULIXES is targeting four major polluted sites on the coastlines of Egypt, Jordan, Morocco and Tunisia, including seashore sands, lagoons, and oil refinery polluted sediments. The research is designed to unravel, categorize, catalogue, exploit and manage the diversity and ecology of microorganisms thriving in these polluted sites. Isolation of novel hydrocarbon degrading microbes and a series of state of the art 'meta-omics' technologies are the baseline tools for improving our knowledge on biodegradation capacities mediated by microbes under different environmental settings and for designing novel site-tailored bioremediation approaches. A network of twelve European and Southern Mediterranean partners is cooperating for plugging the existing gap of knowledge for the development of novel bioremediation processes targeting such poorly investigated polluted sites.

  10. Environmental footprints of Mediterranean versus Western dietary patterns: beyond the health benefits of the Mediterranean diet

    PubMed Central

    2013-01-01

    Background Dietary patterns can substantially vary the resource consumption and environmental impact of a given population. Dietary changes such as the increased consumption of vegetables and reduced consumption of animal products reduce the environmental footprint and thus the use of natural resources. The adherence of a given population to the Mediterranean Dietary Pattern (MDP) through the consumption of the food proportions and composition defined in the new Mediterranean Diet pyramid can thus not only influence human health but also the environment. The aim of the study was to analyze the sustainability of the MDP in the context of the Spanish population in terms of greenhouse gas emissions, agricultural land use, energy consumption and water consumption. Furthermore, we aimed to compare the current Spanish diet with the Mediterranean Diet and in comparison with the western dietary pattern, exemplified by the U.S.A. food pattern, in terms of their corresponding environmental footprints. Methods The environmental footprints of the dietary patterns studied were calculated from the dietary make-up of each dietary pattern, and specific environmental footprints of each food group. The dietary compositions were obtained from different sources, including food balance sheets and household consumption surveys. The specific environmental footprints of food groups were obtained from different available life-cycle assessments. Results The adherence of the Spanish population to the MDP has a marked impact on all the environmental footprints studied. Increasing adherence to the MDP pattern in Spain will reduce greenhouse gas emissions (72%), land use (58%) and energy consumption (52%), and to a lower extent water consumption (33%). On the other hand, the adherence to a western dietary pattern implies an increase in all these descriptors of between 12% and 72%. Conclusions The MDP is presented as not only a cultural model but also as a healthy and environmentally

  11. Mercury in the open Mediterranean: evidence of contamination?

    PubMed

    Aston, S R; Fowler, S W

    1985-05-01

    In relation to the previously observed higher Hg concentrations in the tissues of certain Mediterranean fish (e.g. mackerel and tuna) compared with the same species in the Atlantic, the evidence for anomolously high Hg contamination of the Mediterranean has been examined. Four aspects have been addressed: the reliability of analytical measurements; the paucity of data on Hg in the Mediterranean and other oceanic areas; the actual levels of Hg in truly open-ocean waters; and ecological factors which may play a role in the enrichment of Hg in Mediterranean fish. Recent evidence suggests that former measurements of Hg in sea water are inadequate, and overestimate the concentrations of Hg in oceanic waters. Even today, intercalibration studies suggest that there are serious problems in the determination of Hg at the levels present in open oceans. A comparison of the most recent reliable data indicates that Mediterranean open-ocean waters are not enriched in Hg relative to the North Atlantic or other open-ocean areas. Similarly, no evidence exists for Hg anomalies in deep-ocean sediments in the Mediterranean, although it is apparent that localised coastal anomalies do occur as a result of natural and anthropogenic Hg sources. Generally, there is a severe lack of data on total Hg concentrations in truly open-ocean environments, and virtually no data on alkyl forms of Hg. Geographic comparisons of Hg in plankton and small pelagic fish do not indicate the presence of higher Hg concentrations in the Mediterranean Sea compared with oceanic regimes. Since these lower trophic species serve as a source of food for larger predaceous fish, e.g. tuna, the origin of the high Hg content in top-level predators is difficult to explain by evoking solely food chain relationships. In trying to resolve the question of why high Hg concentrations are found in certain Mediterranean fish, future studies should include an examination of the alkyl as well as inorganic forms of Hg, and

  12. Mediterranean Cyclones in a changing climate. First statistical results

    NASA Astrophysics Data System (ADS)

    Tous, M.; Genoves, A.; Campins, J.; Picornell, M. A.; Jansa, A.; Mizuta, R.

    2009-09-01

    The Mediterranean storms play an important role in weather and climate. Their influence in determining the local weather is known; heavy precipitation systems and strong wind cases are often related to the presence of a cyclone in the Mediterranean. From a large-scale point of view, the Mediterranean storm track has importance in the vertical and horizontal transfers of heat and water vapour towards the Eastern regions. For all of these reasons, any future change related to the intensity, frequency or tracks of these storms can be important for both the local weather and local climate, at least, in the countries around the basin. The Mediterranean cyclones constitute a study subject of increasing interest. Some climatologies from long series of re-analyses, like ERA15, NCEP/NCAR and ERA40, or from operational and high resolution analysis systems, like HIRLAM_INM and ECMWF, have allowed to define the main characteristics of these storms. Generally speaking, the Mediterranean storms have the characteristics of extratropical storms, showing smaller sizes and shorter life cycles than those ones developed in other maritime areas of the world. Moreover, the influence of the land areas and high mountains around the basin and the large-scale heat releases have been revealed as key factors for understanding their genesis and rates of development. In spite of the fact that probably the existing automatic procedures include some large scale assumptions, which may not the best for the correct detection and tracking the Mediterranean storms, these procedures can provide a first and almost necessary step, from a statistical/climatological point of view, specially taking into account both the current resolution of the existent global re-analysis series and global climatic models and the state-of-the art about Mediterranean cyclones. A cyclone detection and tracking procedure, originally designed for the description of Mediterranean storms, has been applied to the low resolution

  13. On the occurrence of the fireworm Eurythoe complanata complex (Annelida, Amphinomidae) in the Mediterranean Sea with an updated revision of the alien Mediterranean amphinomids

    PubMed Central

    Arias, Andrés; Barroso, Rômulo; Anadón, Nuria; Paiva, Paulo C.

    2013-01-01

    Abstract The presence of two species within the Eurythoe complanata complex in the Mediterranean Sea is reported, as well as their geographical distributions. One species, Eurythoe laevisetis, occurs in the eastern and central Mediterranean, likely constituting the first historical introduction to the Mediterranean Sea and the other, Eurythoe complanata, in both eastern and Levantine basins. Brief notes on their taxonomy are also provided and their potential pathways for introduction to the Mediterranean are discussed. A simplified key to the Mediterranean amphinomid genera and species of Eurythoe and Linopherus is presented plus an updated revision of the alien amphinomid species reported previously from the Mediterranean Sea. A total of five exotic species have been included; information on their location, habitat, date of introduction and other relevant features is also provided. PMID:24146576

  14. Management of Solanum elaeagnifolium in the Mediterranean Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solanum elaeagnifolium Cav. (silverleaf nightshade, SOLEL) is a prominent invasive alien weed in many countries of the Mediterranean Basin since its introduction in the mid-20th century, originating from the southwestern United States and northern Mexico. It reproduces vegetatively and by seeds that...

  15. Mycorrhizal Types in the Mediterranean Basin: Safety Teaching and Training

    ERIC Educational Resources Information Center

    Azul, Anabela Marisa; Ramos, Vitor; Pato, Anabela; Azenha, Matilde; Freitas, Helena

    2008-01-01

    More than 90% of vascular plants in terrestrial ecosystems form symbiotic root-fungal associations known as mycorrhiza; in Mediterranean biomes all known mycorrhizal types co-exist. However, the understanding of mycorrhizal diversity and structure and their ecophysiological impact in soil productivity and conservation has been shown to be very…

  16. Temperature humidity index scenarios in the Mediterranean basin.

    PubMed

    Segnalini, M; Bernabucci, U; Vitali, A; Nardone, A; Lacetera, N

    2013-05-01

    The study was undertaken to describe the temperature humidity index (THI) dynamics over the Mediterranean basin for the period 1971-2050. The THI combines temperature and humidity into a single value, and has been widely used to predict the effects of environmental warmth in farm animals. The analysis was based on daily outputs of the temperature and relative humidity from the Max Planck Institute data using the Intergovernmental Panel on Climate Change Special Report Emission Scenario A1B. Data revealed a gradual increase of both annual and seasonal THI during the period under investigation and a strong heterogeneity of the Mediterranean area. In particular, the analysis indicated that Spain, southern France and Italy should be expected to undergo the highest THI increase, which in the last decade under study (2041-2050) will range between 3 and 4 units. However, only during summer months the area presents characteristics indicating risk of thermal (heat) stress for farm animals. In this regard, scenario maps relative to the summer season suggested an enlargement of the areas in the basin where summer THI values will likely cause thermal discomfort in farm animals. In conclusion, the study indicated that the Mediterranean basin is likely to undergo THI changes, which may aggravate the consequences of hot weather on animal welfare, performances, health and survival and may help farmers, nutritionists, veterinarians, and policy-makers to develop appropriate adaptation strategies to limit consequences of climate change for the livestock sector in the Mediterranean countries. PMID:22850789

  17. Climate Change Threatens Coexistence within Communities of Mediterranean Forested Wetlands

    PubMed Central

    Di Paola, Arianna; Valentini, Riccardo; Paparella, Francesco

    2012-01-01

    The Mediterranean region is one of the hot spots of climate change. This study aims at understanding what are the conditions sustaining tree diversity in Mediterranean wet forests under future scenarios of altered hydrological regimes. The core of the work is a quantitative, dynamic model describing the coexistence of different Mediterranean tree species, typical of arid or semi-arid wetlands. Two kind of species, i.e. Hygrophilous (drought sensitive, flood resistant) and Non-hygrophilous (drought resistant, flood sensitive), are broadly defined according to the distinct adaptive strategies of trees against water stress of summer drought and winter flooding. We argue that at intermediate levels of water supply the dual role of water (resource and stress) results in the coexistence of the two kind of species. A bifurcation analysis allows us to assess the effects of climate change on the coexistence of the two species in order to highlight the impacts of predicted climate scenarios on tree diversity. Specifically, the model has been applied to Mediterranean coastal swamp forests of Central Italy located at Castelporziano Estate and Circeo National Park. Our results show that there are distinct rainfall thresholds beyond which stable coexistence becomes impossible. Regional climatic projections show that the lower rainfall threshold may be approached or crossed during the XXI century, calling for an urgent adaptation and mitigation response to prevent biodiversity losses. PMID:23077484

  18. Truth and consequences: the bioinvasion of the Mediterranean Sea.

    PubMed

    Galil, Bella Sarah

    2012-09-01

    Over 660 alien marine multicellular species have been recorded in the Mediterranean Sea, with many establishing viable populations and subsequently dispersing from their points of entry. A brief overview is presented of the current state of knowledge of bioinvasions in the Mediterranean Sea, with particular attention paid to gelatinous invasive species. A database of alien species records was used to characterize their identity, pattern of expansion and native region, and to discuss the relative importance of different taxa and vectors in the various regions of the sea. The temporal and spatial spread of 4 alien scyphozoans and 2 alien ctenophores is outlined. Although thermophilic species constitute the majority of Mediterranean aliens, Erythrean aliens are predominant in the east, with shipping and mariculture being mainly responsible for introductions in the northwest. The propagule pressure driving the Erythrean invasion is powerful in the establishment and spread of alien species in the eastern Mediterranean. The implications of the enlargement of the Suez Canal, reflecting patterns in global trade and economy, are briefly discussed. Finally, as alien species inventories play a pivotal role in informing regional policy and management decisions and identifying resource priorities, the scientific community is called upon to pay particular attention to their accuracy and veracity. PMID:22938526

  19. Management of scorpion stings in Africa and the Mediterranean region.

    PubMed

    Chippaux, J-P

    2016-05-01

    Common in the southern and eastern Mediterranean basin, scorpion stings can develop into a severe medical emergency, especially in young children. Here we review several principles of diagnosis and treatment. The indications for antivenom and symptomatic treatment are detailed according to the symptoms and clinical severity of envenomation.

  20. Pan-African - Mediterranean Migrations: Implications for Education and Society

    ERIC Educational Resources Information Center

    Napier, Diane Brook

    2011-01-01

    The purpose of this study was to examine features of the contemporary migrant and refugee flows across Africa northward to the Mediterranean and then to European countries (sometimes called the "new mass migration" and also migrant flows southward to South Africa. In addition, the purpose was to examine dimensions of response and adaptation in…

  1. Epidemiology of Carbapenem Resistant Klebsiella pneumoniae Infections in Mediterranean Countries

    PubMed Central

    Girmenia, Corrado; Serrao, Alessandra; Canichella, Martina

    2016-01-01

    Infections by Carbapenem-Resistant Enterobacteriaceae (CRE), in particular, carbapenem-resistant Klebsiella pneumoniae (CRKp), are a significant public health challenge worldwide. Resistance to carbapenems in enterobacteriaceae is linked to different mechanisms, including the production of the various types of enzymes like KPC, VIM, IMP, NDM, and OXA-48. Despite several attempts to control the spread of these infections at the local and national level, the epidemiological situation for CRKp had worsened in the last years in the Mediterranean area. The rate and types of CRKp isolates greatly differ in the various Mediterranean countries. KPC-producing K. pneumoniae is diffused particularly in the European countries bordering the Mediterranean Sea and is endemic in Greece and Italy. On the contrary, OXA-48-producing K. pneumoniae is endemic in Turkey and Malta and diffused at inter-regional level particularly in some North African and Middle East countries. The spread of these multiresistant pathogens in the world and the Mediterranean countries has been related to various epidemiological factors including the international transfer of patients coming from endemic areas. PMID:27441063

  2. Temperature humidity index scenarios in the Mediterranean basin

    NASA Astrophysics Data System (ADS)

    Segnalini, M.; Bernabucci, U.; Vitali, A.; Nardone, A.; Lacetera, N.

    2013-05-01

    The study was undertaken to describe the temperature humidity index (THI) dynamics over the Mediterranean basin for the period 1971-2050. The THI combines temperature and humidity into a single value, and has been widely used to predict the effects of environmental warmth in farm animals. The analysis was based on daily outputs of the temperature and relative humidity from the Max Planck Institute data using the Intergovernmental Panel on Climate Change Special Report Emission Scenario A1B. Data revealed a gradual increase of both annual and seasonal THI during the period under investigation and a strong heterogeneity of the Mediterranean area. In particular, the analysis indicated that Spain, southern France and Italy should be expected to undergo the highest THI increase, which in the last decade under study (2041-2050) will range between 3 and 4 units. However, only during summer months the area presents characteristics indicating risk of thermal (heat) stress for farm animals. In this regard, scenario maps relative to the summer season suggested an enlargement of the areas in the basin where summer THI values will likely cause thermal discomfort in farm animals. In conclusion, the study indicated that the Mediterranean basin is likely to undergo THI changes, which may aggravate the consequences of hot weather on animal welfare, performances, health and survival and may help farmers, nutritionists, veterinarians, and policy-makers to develop appropriate adaptation strategies to limit consequences of climate change for the livestock sector in the Mediterranean countries.

  3. Thermal history and petroleum systems of the east Mediterranean realm

    NASA Astrophysics Data System (ADS)

    Daher, Samer Bou; Nader, Fadi H.; Littke, Ralf

    2016-04-01

    The eastern Mediterranean Levant basin is a frontier basin that has gained a lot of industrial and academic interest in the last decade due to the huge gas discoveries that have been reported in its southern part. The reported gas in Miocene reservoirs has been assumed to be derived from biogenic sources, although little data has been published so far. The thickness of the sedimentary column and the presence of direct hydrocarbon indicators (DHI) observed in the seismic data suggest the presence of promising prospective thermogenic petroleum systems in deeper intervals in the Levant Basin and along its margins. The east Mediterranean contains several structural elements dividing the area into different realms that reacted differently to the successive tectonic events that have shaped the area and thus resulted in different thermal and burial histories. We will present source rock data collected within the last few years from several organic matter rich intervals in the east Mediterranean and discuss their depositional environment and petroleum generation potential, as well as the potential petroleum systems in each compartment of the study area. This is based on numerical thermal and burial history models of several east Mediterranean realms including the Levant basin, its eastern and western margins, and the Eratosthenes Seamount. Additionally, we will present some results of sensitivity analysis in the poorly calibrated parts of the study area.

  4. Climate change threatens coexistence within communities of Mediterranean forested wetlands.

    PubMed

    Di Paola, Arianna; Valentini, Riccardo; Paparella, Francesco

    2012-01-01

    The Mediterranean region is one of the hot spots of climate change. This study aims at understanding what are the conditions sustaining tree diversity in Mediterranean wet forests under future scenarios of altered hydrological regimes. The core of the work is a quantitative, dynamic model describing the coexistence of different Mediterranean tree species, typical of arid or semi-arid wetlands. Two kind of species, i.e. Hygrophilous (drought sensitive, flood resistant) and Non-hygrophilous (drought resistant, flood sensitive), are broadly defined according to the distinct adaptive strategies of trees against water stress of summer drought and winter flooding. We argue that at intermediate levels of water supply the dual role of water (resource and stress) results in the coexistence of the two kind of species. A bifurcation analysis allows us to assess the effects of climate change on the coexistence of the two species in order to highlight the impacts of predicted climate scenarios on tree diversity. Specifically, the model has been applied to Mediterranean coastal swamp forests of Central Italy located at Castelporziano Estate and Circeo National Park. Our results show that there are distinct rainfall thresholds beyond which stable coexistence becomes impossible. Regional climatic projections show that the lower rainfall threshold may be approached or crossed during the XXI century, calling for an urgent adaptation and mitigation response to prevent biodiversity losses. PMID:23077484

  5. The Mediterranean Diet and Nutritional Adequacy: A Review

    PubMed Central

    Castro-Quezada, Itandehui; Román-Viñas, Blanca; Serra-Majem, Lluís

    2014-01-01

    The Mediterranean dietary pattern, through a healthy profile of fat intake, low proportion of carbohydrate, low glycemic index, high content of dietary fiber, antioxidant compounds, and anti-inflammatory effects, reduces the risk of certain pathologies, such as cancer or Cardiovascular Disease (CVD). Nutritional adequacy is the comparison between the nutrient requirement and the intake of a certain individual or population. In population groups, the prevalence of nutrient inadequacy can be assessed by the probability approach or using the Estimated Average Requirement (EAR) cut-point method. However, dietary patterns can also be used as they have moderate to good validity to assess adequate intakes of some nutrients. The objective of this study was to review the available evidence on the Nutritional Adequacy of the Mediterranean Diet. The inclusion of foods typical of the Mediterranean diet and greater adherence to this healthy pattern was related to a better nutrient profile, both in children and adults, with a lower prevalence of individuals showing inadequate intakes of micronutrients. Therefore, the Mediterranean diet could be used in public health nutrition policies in order to prevent micronutrient deficiencies in the most vulnerable population groups. PMID:24394536

  6. Management of scorpion stings in Africa and the Mediterranean region.

    PubMed

    Chippaux, J-P

    2016-05-01

    Common in the southern and eastern Mediterranean basin, scorpion stings can develop into a severe medical emergency, especially in young children. Here we review several principles of diagnosis and treatment. The indications for antivenom and symptomatic treatment are detailed according to the symptoms and clinical severity of envenomation. PMID:27412972

  7. Sustainable management for the eastern Mediterranean coast of Turkey.

    PubMed

    Berberoglu, Süha

    2003-03-01

    The objective of this article is to propose a program for the integrated coastal zone management that is required to stimulate and guide sustainable development of the Mediterranean coastal zone of Turkey. Improved data collection, quality control, analysis, and data management will provide a firm basis for future scientific understanding of the East Mediterranean coast of Turkey and will support long-term management. Various innovative procedures were proposed for a promising ecosystem-based approach to manage coastal wetlands in the Mediterranean: remote data acquisition with new technologies; environmental quality monitoring program that will provide a baseline for monitoring; linking a Geographic Information System (GIS) with natural resource management decision routines in the context of operational wetlands, fisheries, tourism management system; environmental sensitivity analysis to ensure that permitted developments are environmentally sustainable; and use of natural species to restore the wetlands and coastal dunes and sustain the system processes. The proposed management scheme will benefit the scientific community in the Mediterranean and the management/planning community in Eastern Turkey.

  8. Loss of large predatory sharks from the Mediterranean Sea.

    PubMed

    Ferretti, Francesco; Myers, Ransom A; Serena, Fabrizio; Lotze, Heike K

    2008-08-01

    Evidence for severe declines in large predatory fishes is increasing around the world. Because of its long history of intense fishing, the Mediterranean Sea offers a unique perspective on fish population declines over historical timescales. We used a diverse set of records dating back to the early 19th and mid 20th century to reconstruct long-term population trends of large predatory sharks in the northwestern Mediterranean Sea. We compiled 9 time series of abundance indices from commercial and recreational fishery landings, scientific surveys, and sighting records. Generalized linear models were used to extract instantaneous rates of change from each data set, and a meta-analysis was conducted to compare population trends. Only 5 of the 20 species we considered had sufficient records for analysis. Hammerhead (Sphyrna spp.), blue (Prionace glauca), mackerel (Isurus oxyrinchus and Lamna nasus), and thresher sharks (Alopias vulpinus) declined between 96 and 99.99% relative to their former abundance. According to World Conservation Union (IUCN) criteria, these species would be considered critically endangered. So far, the lack of quantitative population assessments has impeded shark conservation in the Mediterranean Sea. Our study fills this critical information gap, suggesting that current levels of exploitation put large sharks at risk of extinction in the Mediterranean Sea. Possible ecosystem effects of these losses involve a disruption of top-down control and a release of midlevel consumers.

  9. Editorial Introduction: Multilingualism and Education around the Mediterranean.

    ERIC Educational Resources Information Center

    Bahous, Rima; Thonhauser, Ingo

    2001-01-01

    Introduces a special issue on the complex relationship between multilingualism and education in the Mediterranean region. Articles examine Maltese bilingual education; teaching English in Algeria; shifts in environmental literacy in Lebanon; multilingual education in Lebanon; cognitive-academic language proficiency and language acquisition in…

  10. Loss of genetic diversity as a signature of apricot domestication and diffusion into the Mediterranean Basin

    PubMed Central

    2012-01-01

    Background Domestication generally implies a loss of diversity in crop species relative to their wild ancestors because of genetic drift through bottleneck effects. Compared to native Mediterranean fruit species like olive and grape, the loss of genetic diversity is expected to be more substantial for fruit species introduced into Mediterranean areas such as apricot (Prunus armeniaca L.), which was probably primarily domesticated in China. By comparing genetic diversity among regional apricot gene pools in several Mediterranean areas, we investigated the loss of genetic diversity associated with apricot selection and diffusion into the Mediterranean Basin. Results According to the geographic origin of apricots and using Bayesian clustering of genotypes, Mediterranean apricot (207 genotypes) was structured into three main gene pools: ‘Irano-Caucasian’, ‘North Mediterranean Basin’ and ‘South Mediterranean Basin’. Among the 25 microsatellite markers used, only one displayed deviations from the frequencies expected under neutrality. Similar genetic diversity parameters were obtained within each of the three main clusters using both all SSR loci and only 24 SSR loci based on the assumption of neutrality. A significant loss of genetic diversity, as assessed by the allelic richness and private allelic richness, was revealed from the ‘Irano-Caucasian’ gene pool, considered as a secondary centre of diversification, to the northern and southwestern Mediterranean Basin. A substantial proportion of shared alleles was specifically detected when comparing gene pools from the ‘North Mediterranean Basin’ and ‘South Mediterranean Basin’ to the secondary centre of diversification. Conclusions A marked domestication bottleneck was detected with microsatellite markers in the Mediterranean apricot material, depicting a global image of two diffusion routes from the ‘Irano-Caucasian’ gene pool: North Mediterranean and Southwest Mediterranean. This study

  11. Mediterranean extension and the Africa-Eurasia collision

    NASA Astrophysics Data System (ADS)

    Jolivet, Laurent; Faccenna, Claudio

    2000-12-01

    A number of tectonic events occurred contemporaneously in the Mediterranean region and the Middle East 30-25 Myr ago. These events are contemporaneous to or immediately followed a strong reduction of the northward absolute motion of Africa. Geological observations in the Neogene extensional basins of the Mediterranean region reveal that extension started synchronously from west to east 30-25 Myr ago. In the western Mediterranean it started in the Gulf of Lion, Valencia trough, and Alboran Sea as well as between the Maures massif and Corsica between 33 and 27 Ma ago. It then propagated eastward and southward to form to Liguro-Provençal basin and the Tyrrhenian Sea. In the eastern Mediterranean, extension started in the Aegean Sea before the deposition of marine sediments onto the collapsed Hellenides in the Aquitanian and before the cooling of high-temperature metamorphic core complexes between 20 and 25 Ma. Foundering of the inner zones of the Carpathians and extension in the Panonnian basin also started in the late Oligocene-early Miocene. The body of the Afro-Arabian plate first collided with Eurasia in the eastern Mediterranean region progressively from the Eocene to the Oligocene. Extensional tectonics was first recorded in the Gulf of Aden, Afar triple junction, and Red Sea region also in the Oligocene. A general magmatic surge occurred above all African hot spots, especially the Afar one. We explore the possibility that these drastic changes in the stress regime of the Mediterranean region and Middle East and the contemporaneous volcanic event were triggerred by the Africa/Arabia-Eurasia collision, which slowed down the motion of Africa. The present-day Mediterranean Sea was then locked between two collision zones, and the velocity of retreat of the African slab increased and became larger than the velocity of convergence leading to backarc extension. East of the Caucasus and northern Zagros collision zone the Afro-Arabian plate was still pulled by the slab

  12. Climate change and drought risk management in Mediterranean watersheds (Invited)

    NASA Astrophysics Data System (ADS)

    Pulwarty, R. S.; Maia, R.; Garrido, A.; Hoerling, M. P.

    2013-12-01

    As a result of major droughts and floods over the past two decades, the European Union has expressed major concerns regarding climate change impacts on the resilience of ecosystems and water resources. The EU Water Framework Directive established a framework for action in the field of water olicy committing European Union member states to achieve develop integrated watershed management plans and improve the quality of water bodies by 2015. Key to meeting these goals are understanding and planning for changes in extreme events, groundwater and surface water changes, and the level of integrated water resources management infrastructure. In the northern European basins, water shortages are mostly offset by irrigation systems. This is not the case for southern basins in the Mediterranean (e.g. Guadiana, Ebro, Po), where water supply systems are already stressed, and where socioeconomic losses due to droughts are more significant. Precipitation variability in the Mediterranean basin is characterized by substantial interdecadal variations and long-term trends. This paper presents an assessment of climate and the socioeconomic impacts of drought in the Mediterranean basin including the factors that determine the vulnerability of different sectors to the risks posed by climate change. The studies are based on two projects in which the authors are involved: the European Commission funded PREEMPT project 'Policy-relevant assessment of the socio-economic effects of droughts and floods' and 'Development of methodologies for integration of climate change on water resources managements for the Guadiana Basin', that analyze drought events, economic losses, risk management efforts and the prospect for adaptation. Studies show that the land area surrounding the Mediterranean Sea has experienced 10 of the 12 driest winters since 1902 in just the last 20 years. A change in wintertime Mediterranean precipitation toward drier conditions has likely occurred over 1902-2010. Anthropogenic

  13. Climate change and forest fires in a Mediterranean environment

    NASA Astrophysics Data System (ADS)

    Turco, Marco; Llasat, Maria-Carmen; von Hardenberg, Jost; Provenzale, Antonello

    2014-05-01

    The Mediterranean region is a "hot-spot" of climate change and wildfires, where about 50000 fires burn 500000 hectares every year. However, in spite of the growing concerns of the climate change impacts on Mediterranean wildfires, there are aspects of this topic that remain largely to be investigated. The main scientific objective of this study is to investigate the climate-driven changes on fires in a typical Mediterranean environment (Catalonia, NE of Spain). To achieve this goal, the following specific aims have been identified: (1) Analysis of the recent evolution of fires; (2) Evaluation of the climate-fire relationship; (3) Estimation of the impacts of observed and future climate change. First, we examine a homogeneous series of forest fires in the period 1970-2010. Our analysis shows that both the burned area and number of fire series display a decreasing trend. After the large fires of 1986 and 1994, the increased effort in fire prevention and suppression could explain part of this decreasing trend. Although it is often stated that fires have increased in Mediterranean regions, the higher efficiency in fire detection could have led to spurious trends and misleading conclusions [1]. Secondly, we show that the interannual variability of summer fires is significantly related to antecedent and concurrent climate conditions, highlighting the importance of climate not only in regulating fuel flammability, but also fuel load. On the basis of these results, we develop a simple regression model that produces reliable out-of-sample predictions of the impact of climate variability on summer forest fires [2]. Finally we apply this model to estimate the impacts of observed climate trends on summer fires and the possible fire response to different regional climate change scenarios. We show that a transition toward warmer conditions has already started to occur and it is possible that they continue by mid-century (under the A1B scenario), and that these changes promote

  14. ACAM, a novel member of the neural IgCAM family, mediates anterior neural tube closure in a primitive chordate.

    PubMed

    Morales Diaz, Heidi; Mejares, Emil; Newman-Smith, Erin; Smith, William C

    2016-01-01

    The neural IgCAM family of cell adhesion molecules, which includes NCAM and related molecules, has evolved via gene duplication and alternative splicing to allow for a wide range of isoforms with distinct functions and homophilic binding properties. A search for neural IgCAMs in ascidians (Ciona intestinalis, Ciona savignyi, and Phallusia mammillata) has identified a novel set of truncated family members that, unlike the known members, lack fibronectin III domains and consist of only repeated Ig domains. Within the tunicates this form appears to be unique to the ascidians, and it was designated ACAM, for Ascidian Cell Adhesion Molecule. In C. intestinalis ACAM is expressed in the developing neural plate and neural tube, with strongest expression in the anterior sensory vesicle precursor. Unlike the two other conventional neural IgCAMs in C. intestinalis, which are expressed maternally and throughout the morula and blastula stages, ACAM expression initiates at the gastrula stage. Moreover, C. intestinalis ACAM is a target of the homeodomain transcription factor OTX, which plays an essential role in the development of the anterior central nervous system. Morpholino (MO) knockdown shows that ACAM is required for neural tube closure. In MO-injected embryos neural tube closure was normal caudally, but the anterior neuropore remained open. A similar phenotype was seen with overexpression of a secreted version of ACAM. The presence of ACAM in ascidians highlights the diversity of this gene family in morphogenesis and neurodevelopment. PMID:26542009

  15. Continental Supply and Climate Variations In Mediterranean Pliocene

    NASA Astrophysics Data System (ADS)

    Foucault, Alain; Melieres, Frederic; Combourieu-Nebaout, Nathalie

    From the Pliocene period to present day, the Mediterranean marine sedimentation is characterised by cycles resulting from climate variations, which are controlled by Earth orbital parameters. Theses cycles are evidenced in the sediment content vari- ation, particularly through composition and proportions of the material supplied by continents. Concerning mineral supply we were able to show alternations of humid pe- riods, during which fluvial supply is dominant, and arid periods, during which eolian supply from the southern borderlands of the Mediterranean is significant. Concerning organic supply, palynological study confirms theses climatic controls, emphasising the importance of fresh water runoff during humid periods. This synthetic image re- sults from the study of several Pliocene Mediterranean stratigraphical series located in Sicily (Lido Rosselo, Punta di Maiata, Punta Piccola), Calabria (Monte Singa, Vrica) or cored during Leg 160 ODP (Hole 964). References: FOUCAULT A. et MELIERES F. (1995).- Nature et origine des cy- cles sédimentaires métriques du Pliocène de l'Ouest méditerranéen d'après l'étude du contenu terrigène de la Formation Narbone (Punta Piccola, Sicile, Italie). C. R Ac. Sci. Paris, t. 321, II a, p. 869-876. MELIERES F., FOUCAULT A. and BLANC-VALLERON, M.M. (1998). Mineralogical record of cyclic climate changes in Mediterranean Mid-Pliocene deposits from Hole 964A (Ionian Basin) and from Punta Piccola (Sicily). In Robertson, A.H.F., Emeis, K.-C., Richter, C., and Camer- lenghi, A. (Eds.), 1998. Proc. ODP., Sci. Results, 160; College Station, TX (Ocean Drilling Program), p. 219-226. FOUCAULT, A. and MELIERES, F. (2000). Palaeocli- mate cyclicity in central Mediterranean Pliocene sediments: the mineralogical signal. Palaeogeography, Palaeoclimatology, Palaeoecology, 148: 311-323.

  16. Mediterranean fruit fly as a potential vector of bacterial pathogens.

    PubMed

    Sela, Shlomo; Nestel, David; Pinto, Riky; Nemny-Lavy, Esther; Bar-Joseph, Moshe

    2005-07-01

    The Mediterranean fruit fly (Ceratitis capitata) is a cosmopolitan pest of hundreds of species of commercial and wild fruits. It is considered a major economic pest of commercial fruits in the world. Adult Mediterranean fruit flies feed on all sorts of protein sources, including animal excreta, in order to develop eggs. After reaching sexual maturity and copulating, female flies lay eggs in fruit by puncturing the skin with their ovipositors and injecting batches of eggs into the wounds. In view of the increase in food-borne illnesses associated with consumption of fresh produce and unpasteurized fruit juices, we investigated the potential of Mediterranean fruit fly to serve as a vector for transmission of human pathogens to fruits. Addition of green fluorescent protein (GFP)-tagged Escherichia coli to a Mediterranean fruit fly feeding solution resulted in a dose-dependent increase in the fly's bacterial load. Flies exposed to fecal material enriched with GFP-tagged E. coli were similarly contaminated and were capable of transmitting E. coli to intact apples in a cage model system. Washing contaminated apples with tap water did not eliminate the E. coli. Flies inoculated with E. coli harbored the bacteria for up to 7 days following contamination. Fluorescence microscopy demonstrated that the majority of fluorescent bacteria were confined along the pseudotrachea in the labelum edge of the fly proboscis. Wild flies captured at various geographic locations were found to carry coliforms, and in some cases presumptive identification of E. coli was made. These findings support the hypothesis that the common Mediterranean fruit fly is a potential vector of human pathogens to fruits. PMID:16000820

  17. Comparative Patterns of Plant Invasions in the Mediterranean Biome

    PubMed Central

    Arianoutsou, Margarita; Delipetrou, Pinelopi; Vilà, Montserrat; Dimitrakopoulos, Panayiotis G.; Celesti-Grapow, Laura; Wardell-Johnson, Grant; Henderson, Lesley; Fuentes, Nicol; Ugarte-Mendes, Eduardo; Rundel, Philip W.

    2013-01-01

    The objective of this work was to compare and contrast the patterns of alien plant invasions in the world’s five mediterranean-climate regions (MCRs). We expected landscape age and disturbance history to have bearing on levels of invasion. We assembled a database on naturalized alien plant taxa occurring in natural and semi-natural terrestrial habitats of all five regions (specifically Spain, Italy, Greece and Cyprus from the Mediterranean Basin, California, central Chile, the Cape Region of South Africa and Southwestern - SW Australia). We used multivariate (hierarchical clustering and NMDS ordination) trait and habitat analysis to compare characteristics of regions, taxa and habitats across the mediterranean biome. Our database included 1627 naturalized species with an overall low taxonomic similarity among the five MCRs. Herbaceous perennials were the most frequent taxa, with SW Australia exhibiting both the highest numbers of naturalized species and the highest taxonomic similarity (homogenization) among habitats, and the Mediterranean Basin the lowest. Low stress and highly disturbed habitats had the highest frequency of invasion and homogenization in all regions, and high natural stress habitats the lowest, while taxonomic similarity was higher among different habitats in each region than among regions. Our analysis is the first to describe patterns of species characteristics and habitat vulnerability for a single biome. We have shown that a broad niche (i.e. more than one habitat) is typical of naturalized plant species, regardless of their geographical area of origin, leading to potential for high homogenization within each region. Habitats of the Mediterranean Basin are apparently the most resistant to plant invasion, possibly because their landscapes are generally of relatively recent origin, but with a more gradual exposure to human intervention over a longer period. PMID:24244443

  18. Travelling in the eastern Mediterranean with landscape character assessment

    NASA Astrophysics Data System (ADS)

    Abu Jaber, N.; Abunnasr, Y.; Abu Yahya, A.; Boulad, N.; Christou, O.; Dimitropoulos, G.; Dimopoulos, T.; Gkoltsiou, K.; Khreis, N.; Manolaki, P.; Michael, K.; Odeh, T.; Papatheodoulou, A.; Sorotou, A.; Sinno, S.; Suliman, O.; Symons, N.; Terkenli, T.; Trigkas, Vassilis; Trovato, M. G.; Victora, M.; Zomeni, M.; Vogiatzakis, I. N.

    2015-06-01

    Following its application in Northern Europe, Landscape Character Assessment has also been implemented in Euro-Mediterranean countries as a tool for classifying, describing and assessing landscapes. Many landscape classifications employed in the Euro-Mediterranean area are similar in philosophy and application to the ones developed in Northern Europe. However, many aspects of landform, climate, land-use and ecology, as well as socio-economic context are distinctive of Mediterranean landscapes. The paper discusses the conceptual and methodological issues faced during landscape mapping and characterisation in four East-Mediterranean countries (within the MEDSCAPES project): Cyprus, Greece, Jordan and Lebanon. The major hurdles to overcome during the first phase of methodology development include variation in availability, quality, scale and coverage of spatial datasets between countries and also terminology semantics around landscapes. For example, the concept of landscape - a well-defined term in Greek and English - did not exist in Arabic. Another issue is the use of relative terms like 'high mountains,' `uplands' `lowlands' or ' hills'. Such terms, which are regularly used in landscape description, were perceived slightly differently in the four participating countries. In addition differences exist in nomenclature and classification systems used by each country for the dominant landscape-forming factors i.e. geology, soils and land use- but also in the cultural processes shaping the landscapes - compared both to each other and to the Northern-European norms. This paper argues for the development of consistent, regionally adapted, relevant and standardised methodologies if the results and application of LCA in the eastern Mediterranean region are to be transferable and comparable between countries.

  19. Acidification of the Mediterranean Sea from anthropogenic carbon penetration

    NASA Astrophysics Data System (ADS)

    Hassoun, Abed El Rahman; Gemayel, Elissar; Krasakopoulou, Evangelia; Goyet, Catherine; Abboud-Abi Saab, Marie; Guglielmi, Véronique; Touratier, Franck; Falco, Cédric

    2015-08-01

    This study presents an estimation of the anthropogenic CO2 (CANT) concentrations and acidification (ΔpH=pH2013-pHpre-industrial) in the Mediterranean Sea, based upon hydrographic and carbonate chemistry data collected during the May 2013 MedSeA cruise. The concentrations of CANT were calculated using the composite tracer TrOCA. The CANT distribution shows that the most invaded waters (>60 μmol kg-1) are those of the intermediate and deep layers in the Alboran, Liguro- and Algero-Provencal Sub-basins in the Western basin, and in the Adriatic Sub-basin in the Eastern basin. Whereas the areas containing the lowest CANT concentrations are the deep layers of the Eastern basin, especially those of the Ionian Sub-basin, and those of the northern Tyrrhenian Sub-basin in the Western basin. The acidification level in the Mediterranean Sea reflects the excessive increase of atmospheric CO2 and therefore the invasion of the sea by CANT. This acidification varies between -0.055 and -0.156 pH unit and it indicates that all Mediterranean Sea waters are already acidified, especially those of the Western basin where ΔpH is rarely less than -0.1 pH unit. Both CANT concentrations and acidification levels are closely linked to the presence and history of the different water masses in the intermediate and deep layers of the Mediterranean basins. Despite the high acidification levels, both Mediterranean basins are still highly supersaturated in calcium carbonate minerals.

  20. Mediterranean Diet and Mobility Decline in Older Persons

    PubMed Central

    Milaneschi, Yuri; Bandinelli, Stefania; Corsi, Anna Maria; Lauretani, Fabrizio; Paolisso, Giuseppe; Dominguez, Ligia J.; Semba, Richard D; Tanaka, Toshiko; Abbatecola, Angela M; Talegawkar, Sameera A; Guralnik, Jack M.; Ferrucci, Luigi

    2010-01-01

    We examined whether adherence to a Mediterranean-style diet has positive effects on mobility assessed over a nine-year follow-up in a representative sample of older adults. This research is part of the InCHIANTI Study, a prospective population-based study of older persons in Tuscany, Italy. The sample for this analysis included 935 women and men aged 65 years and older. Adherence to the Mediterranean diet was assessed at baseline by the standard 10-unit Mediterranean diet score (MDS). Lower extremity function was measured at baseline, and at the 3, 6 and 9-year follow-up visits using the Short Physical Performance Battery (SPPB). At baseline, higher adherence to Mediterranean diet was associated with better lower body performance. Participants with higher adherence experienced less decline in SPPB score, which was of 0.9 points higher (p<.0001) at the 3-year-follow, 1.1 points higher (p= 0.0004) at the 6-year follow-up and 0.9 points higher (p= 0.04) at the 9-year follow-up compared to those with lower adherence. Among participants free of mobility disability at baseline, those with higher adherence had a lower risk (HR=0.71,95%CI=0.51–0.98, p=0.04) of developing new mobility disability. High adherence to a Mediterranean-style diet is associated with a slower decline of mobility over time in community dwelling older persons. If replicated, this observation is highly relevant in terms of public health. PMID:21111801

  1. "Once upon a time in the Mediterranean" long term trends of Mediterranean fisheries resources based on fishers' Traditional Ecological Knowledge.

    PubMed

    Damalas, Dimitrios; Maravelias, Christos D; Osio, Giacomo C; Maynou, Francesc; Sbrana, Mario; Sartor, Paolo

    2015-01-01

    We investigate long-term changes in the Mediterranean marine resources driving the trawl fisheries by analysing fishers' perceptions (Traditional Ecological Knowledge, TEK) throughout the Mediterranean Sea during the last 80 years. To this end, we conducted an extended set of interviews with experienced fishers that enabled us to classify species (or taxa) as 'decreasing' or 'increasing' both in terms of abundance, as well as average size in the catch. The aspect that most clearly emerged in all the investigated areas over time was the notable increase of fishing capacity indicators, such as engine power and fishing depth range. Atlantic mackerel, poor cod, scorpionfishes, striped seabream, and John Dory demonstrated a decreasing trend in the fishers' perceived abundance, while Mediterranean parrotfish, common pandora, cuttlefish, blue and red shrimp, and mullets gave indications of an increasing temporal trend. Although, as a rule, trawler captains did not report any cataclysmic changes (e.g. extinctions), when they were invited to estimate total catches, a clear decreasing pattern emerged; this being a notable finding taking into account the steep escalation of fishing efficiency during the past century. The overall deteriorating status of stocks in most Mediterranean regions calls for responsible management and design of rebuilding plans. This should include historical information accounting for past exploitation patterns that could help defining a baseline of fish abundance prior to heavy industrial fisheries exploitation. PMID:25781459

  2. "Once upon a time in the Mediterranean" long term trends of Mediterranean fisheries resources based on fishers' Traditional Ecological Knowledge.

    PubMed

    Damalas, Dimitrios; Maravelias, Christos D; Osio, Giacomo C; Maynou, Francesc; Sbrana, Mario; Sartor, Paolo

    2015-01-01

    We investigate long-term changes in the Mediterranean marine resources driving the trawl fisheries by analysing fishers' perceptions (Traditional Ecological Knowledge, TEK) throughout the Mediterranean Sea during the last 80 years. To this end, we conducted an extended set of interviews with experienced fishers that enabled us to classify species (or taxa) as 'decreasing' or 'increasing' both in terms of abundance, as well as average size in the catch. The aspect that most clearly emerged in all the investigated areas over time was the notable increase of fishing capacity indicators, such as engine power and fishing depth range. Atlantic mackerel, poor cod, scorpionfishes, striped seabream, and John Dory demonstrated a decreasing trend in the fishers' perceived abundance, while Mediterranean parrotfish, common pandora, cuttlefish, blue and red shrimp, and mullets gave indications of an increasing temporal trend. Although, as a rule, trawler captains did not report any cataclysmic changes (e.g. extinctions), when they were invited to estimate total catches, a clear decreasing pattern emerged; this being a notable finding taking into account the steep escalation of fishing efficiency during the past century. The overall deteriorating status of stocks in most Mediterranean regions calls for responsible management and design of rebuilding plans. This should include historical information accounting for past exploitation patterns that could help defining a baseline of fish abundance prior to heavy industrial fisheries exploitation.

  3. Degradation of terraced slopes in Mediterranean conditions

    NASA Astrophysics Data System (ADS)

    Tsermegas, I.; DłuŻewski, M.; Biejat, K.; Szynkiewicz, A.

    2012-04-01

    Agricultural terraces with dry-stone walls take the largest area of all man-made landforms in Mediterranean mountain regions. Despite on that their contemporary morphodynamics have not been the subject of many studies. It is a significant problem both from a scientific and a practical point of view. The aim of the study was to estimate the influence of relief, lithology, climatic conditions, methods of wall construction and actual agricultural practice on the degradation of agricultural terraces. A field study was conducted in Greece on 7 plots with the overall area of over 42 000 m2 - on the east Crete and on two Aegean islands - Ikaria and Thera. The analysis was conducted on terraced slopes with gradient of 8-23o, built of granitoids, gneisses, crystalline schists, limestones, crystalline dolomites and volcanic tuffs. There was identified the types of terrace walls. Metrical features of terrace systems were ascertained on the basis of GPS RTK measurement. Terrace material petrography and grain size distribution was identified for regolith an soil samples taken from the selected outcrops which were recognized as being representative for 239 georadar profiles of the joint length of over 2500 m. On that basis the volume of each terrace material was defined. The rills cutting the fields and the walls were measured. The infiltration rate was also taken in 130 points. Reasearch showed that regardless of metrical features of terraces, soil grain size distribution and thickness of the terrace material, the most important reason for the destruction of terrace walls is the abandonment of cultivated areas. Changes in cultivation methods and the introduction of pasturage visibly accelerate the degradation processes. On areas unused for 30 years terrace walls are destroyed on over 25% of their length. It concerns both the areas on which filtration coefficient (k) reaches about 10-5m•s-1 as well as the ones where it is a 100 times lower. The least varied values (10-6-10-5m

  4. Long term successful weight loss with a combination biphasic ketogenic Mediterranean diet and Mediterranean diet maintenance protocol.

    PubMed

    Paoli, Antonio; Bianco, Antonino; Grimaldi, Keith A; Lodi, Alessandra; Bosco, Gerardo

    2013-12-01

    Weight loss protocols can only be considered successful if they deliver consistent results over the long term-a goal which is often elusive, so much so that the term "yo-yo" is used to describe the perennial weight loss/weight regain battle common in obesity. We hypothesized that a ketogenic Mediterranean diet with phytoextracts (KEMEPHY) combined with the acknowledged health benefits of traditional Mediterranean nutrition may favor long term weight loss. We analysed 89 male and female obese subjects, aged between 25 and 65 years who were overall healthy apart from being overweight. The subjects followed a staged diet protocol over a period of 12 months: 20 day of KEMEPHY; 20 days low carb-non ketogenic; 4 months Mediterranean normocaloric nutrition; a second 20 day ketogenic phase followed by 6 months of Mediterranean normocaloric nutrition. For the majority of subjects (88.25%) there was significant loss of weight (from 100.7 ± 16.54 to 84.59 ± 9.71 kg; BMI from 35.42 ± 4.11 to 30.27 ± 3.58) and body fat (form 43.44% ± 6.34% to 33.63% ± 7.6%) during both ketogenic phases followed by successful maintenance, without weight regain, during the 6 month stabilization phase with only 8 subjects failing to comply. There were also significant and stable decreases in total cholesterol, LDLc, triglycerides and glucose levels over the 12 month study period. HDLc showed small increases after the ketogenic phases but over the full 12 months there was no significant change. No significant changes were observed in ALT, AST, Creatinine or BUN. The combination of a biphasic KEMEPHY diet separated by longer periods of maintenance nutrition, based on the traditional Mediterranean diet, led to successful long term weight loss and improvements in health risk factors in a majority of subjects; compliance was very high which was a key determinant of the results seen. PMID:24352095

  5. Kinematic restoration of the Mediterranean region since the Triassic

    NASA Astrophysics Data System (ADS)

    van Hinsbergen, Douwe; Torsvik, Trond; Matenco, Liviu; Schmid, Stefan; Maffione, Marco; Spakman, Wim

    2014-05-01

    The Mediterranean region is one of the most complexly deformed areas in the world and its tectonic evolution has been instrumental in the development of numerous fundamental geological principles and geodynamic concepts. Reconstructions of the Mediterranean region invariably demonstrated that the area had a complex paleogeography with ribbon continents or micro-plates and narrow, elongated ocean basins systems in Mesozoic time. A western and northern ocean basin system was genetically related to the Atlantic Ocean, opened in Jurassic time and is known as the Alpine Tethys Ocean. A southern and eastern basin system was genetically related to the Neotethys domain located between Gondwana and Eurasia and - in the Mediterranean realm - opened in Triassic to Jurassic times. Continental domains of variable size within and between these ocean systems rifted away from Eurasia or Africa. This mosaic of pieces of continental and oceanic lithosphere became consumed by a complex configuration of subduction zones that accommodated convergence between the African and Eurasian plates since middle Jurassic times. Since Oligocene time, the overriding plate above subduction zones throughout the Mediterranean region became extended, locally leading to formation of new ocean floor, as a result of roll-back of subducted slab segments, culminating in todays complex and strongly curved configuration of subduction zones and slab segments. An area such as the tectonically complex Mediterranean invites attempt to kinematic restoration, and various reconstructions are already available. However, by now such reconstructions are no more merely a translation of - frequently qualitative - geological data into a quantitative description of surface evolution: with the advent of 3-dimensional numerical modeling tools that can be kinematically driven by plate reconstructions, they become critical input for attempts to integrate surface evolution into mantle dynamics. An increasingly widely used

  6. A Classification of Mediterranean Cyclones Based on Global Analyses

    NASA Technical Reports Server (NTRS)

    Reale, Oreste; Atlas, Robert

    2003-01-01

    The Mediterranean Sea region is dominated by baroclinic and orographic cyclogenesis. However, previous work has demonstrated the existence of rare but intense subsynoptic-scale cyclones displaying remarkable similarities to tropical cyclones and polar lows, including, but not limited to, an eye-like feature in the satellite imagery. The terms polar low and tropical cyclone have been often used interchangeably when referring to small-scale, convective Mediterranean vortices and no definitive statement has been made so far on their nature, be it sub-tropical or polar. Moreover, most of the classifications of Mediterranean cyclones have neglected the small-scale convective vortices, focusing only on the larger-scale and far more common baroclinic cyclones. A classification of all Mediterranean cyclones based on operational global analyses is proposed The classification is based on normalized horizontal shear, vertical shear, scale, low versus mid-level vorticity, low-level temperature gradients, and sea surface temperatures. In the classification system there is a continuum of possible events, according to the increasing role of barotropic instability and decreasing role of baroclinic instability. One of the main results is that the Mediterranean tropical cyclone-like vortices and the Mediterranean polar lows appear to be different types of events, in spite of the apparent similarity of their satellite imagery. A consistent terminology is adopted, stating that tropical cyclone- like vortices are the less baroclinic of all, followed by polar lows, cold small-scale cyclones and finally baroclinic lee cyclones. This classification is based on all the cyclones which occurred in a four-year period (between 1996 and 1999). Four cyclones, selected among all the ones which developed during this time-frame, are analyzed. Particularly, the classification allows to discriminate between two cyclones (occurred in October 1996 and in March 1999) which both display a very well

  7. Erosion in Mediterranean landscapes: Changes and future challenges

    NASA Astrophysics Data System (ADS)

    García-Ruiz, José M.; Nadal-Romero, Estela; Lana-Renault, Noemí; Beguería, Santiago

    2013-09-01

    Intense erosion processes are widespread in the Mediterranean region, and include sheet wash erosion, rilling, gullying, shallow landsliding, and the development of large and active badlands in both subhumid and semi-arid areas. This review analyses the main environmental and human features related to soil erosion processes, and the main factors that explain the extreme variability of factors influencing soil erosion, particularly recent land use changes. The importance of erosion in the Mediterranean is related to the long history of human activity in a region characterized by low levels of annual precipitation, the occurrence of intense rainstorms and long-lasting droughts, high evapotranspiration, the presence of steep slopes and the occurrence of recent tectonic activity, together with the recurrent use of fire, overgrazing and farming. These factors have resulted in a complex landscape in which intensification and abandonment, wealth and poverty can co-exist. The changing conditions of national and international markets and the evolution of population pressure are now the main drivers explaining land use changes, including farmland abandonment in mountain areas, the expansion of some subsidized crops to marginal lands, and the development of new terraces affected by landslides and intense soil erosion during extreme rainstorm events. The occurrence of human-related forest fires affecting thousands of hectares each year is a significant problem in both the northern and southern areas of the Mediterranean basin. Here, we highlight the rise of new scientific challenges in controlling the negative consequences of soil erosion in the Mediterranean region: 1) to reduce the effects and extent of forest fires, and restructure the spatial organization of abandoned landscapes; 2) to provide guidance for making the EU agricultural policy more adapted to the complexity and fragility of Mediterranean environments; 3) to develop field methods and models to improve the

  8. Temperature changes along the Spanish Mediterranean shelf waters

    NASA Astrophysics Data System (ADS)

    Vargas-Yanez, M.; Lopez-Jurado, J. L.; Salat, J.; Pascual, J.

    2003-04-01

    Temperature and salinity of intermediate and deep waters of the western Mediterranean have rised during the XX century. These changes are well documented in the specialised literature (Bethoux et al., 1998, Rholing and Bryden, 1992, Tsimplis and Baker, 2000). Nevertheless it is not yet clear whether these changes are due to global warming and a change in the deep water formation conditions in the western Mediterranean or if it is imported from the eastern basin. In the second case, an increase of salinity of the eastern basin due to damming of the main rivers would be the main cause. Trend detection in coastal waters where intermediate waters influence is negligible, would help to clarify this problem. Nevertheless, it is more difficult to detect significant trends in coastal waters due to the intense noise and seasonal cycles superimposed to these trends (if existing). The number of degrees of freedom needed for the significant detection is higher and regular sampling programs are needed. Unfortunately, standard stations periodically sampled are scarce. Here we present results from two of these periodic programs conducted by IEO and ICM along the Spanish Mediterranean shelf (RADIALES project and L'startit coastal station). This work is divided into two parts. The first one is devoted to the revision of the main hypothesis involved in the statistic treatment of time series, such as normal distribution, independence of residuals, seasonal cycles removing, etc...., while the second part will focus on the comparison of time series along the Spanish coast, the study of temperature trends and its possible relation with NAO index. The most striking result is the detection of a intense warming trend which is common to the north-western and south-western stations for the last part of the XX century. Bibliography. Bethoux, J.P., B. Gentili, D. Taillez, warming and freshwater budget change in the Mediterranean since the 1940s, their possible relation to the greenhouse effect

  9. Understanding the Miocene-Pliocene - The Mediterranean Point of View

    NASA Astrophysics Data System (ADS)

    Simon, D.; Marzocchi, A.; Lunt, D. J.; Flecker, R.; Hilgen, F. J.; Meijer, P. T.

    2015-12-01

    During the Miocene-Pliocene the Mediterranean region experienced major changes in paleogeography. Today, its only connection to the global ocean is the Strait of Gibraltar. This restricted nature causes the Mediterranean basin to react more sensitive to climatic and tectonic related phenomena than the global ocean: Not just eustatic sea-level and regional river run-off, but also gateway tectonics and connectivity between sub-basins are leaving an enhanced fingerprint in its geological record. To understand its evolution, it is crucial to understand how these different effects are coupled. The Miocene-Pliocene sedimentary record of the Mediterranean alternates in composition and colour. Around the Miocene-Pliocene Boundary the most extreme changes occur in the Mediterranean Sea: About 6% of the salt in the global ocean got deposited in the Mediterranean Region, forming an approximately 2km thick salt layer, which is still present today. This extreme event is named the Messinian Salinity Crisis (MSC, 5.97-5.33Ma). Before (and also after) the MSC, the sedimentary record demonstrates "marl dominated" alternations with variations in organic content (e.g. higher organic content = sapropel). During the MSC these change to mainly "evaporite (e.g. gypsum or halite) dominated" alternations, but also to brackish Black Sea-type of deposits towards the end of the crisis. Due to its relative short geological time span, the period before, during and after the MSC is ideal to study these extreme changes in sedimentation. We are investigating these couplings and evolutions in a box/budget model. With such a model we can study the responses to basin water exchange dynamics under the effect of different regional and global climatic and tectonic forcings, to predict the evolution of basin properties (e.g. salinity). By doing so we can isolate certain climatic and tectonic effects, to better understand their individual contribution, their interaction, but also the consequences due to

  10. Seismic noise recored by seafloor observatories at Mediterranean sites

    NASA Astrophysics Data System (ADS)

    De Caro, Mariagrazia; Monna, Stephen; Frugoni, Francesco; Beranzoli, Laura; Favali, Paolo

    2015-04-01

    The Mediterranean region is an area highly exposed to geo-hazards, such as seismic and volcanic activity. Real-time and continuous monitoring of its coastal areas is needed to ensure rapid warning and mitigate the effects of natural disasters. Seafloor observatories for near-real-time and real-time interactive long-term monitoring of ocean processes which are part of the EMSO (European Multidisciplinary Seafloor and water-column Observatory, www.emso-eu.org) Research Infrastructure, have been deployed in sites of the Mediterranean basin. We present long-term time series acquired by GEOSTAR-class seafloor observatories deployed in four sites of Mediterranean areas: Ionian and Tyrrhenian Seas (deep seafloor Central-Mediterranean sites) and the Marmara Sea and Gulf of Corinth (shallow seafloor Eastern-Mediterranean sites). We generated a reference model of the background seismic noise based on data collected from seismometers installed on board seafloor observatories. We concentrate on interesting and peculiar features of the noise signal in the frequency band 0.003-50 Hz. The main contribution in the short period band >5Hz (<2s) comes from anthropic noise (e.g. shipping noise). In this band we also find a peak around 0.8Hz (1.25s) which appears to be a persistent characteristic of the Mediterranean basins. Seasonal variations (summer-winter) are visible in the microseismic band 0.05-0.5Hz (2-20s). In particular in the Ionian and Tyrrhenian deep seafloor sites we can distinguish the splitting of the DF (Double Frequency peak) in the long period (LPDF) and the short period (SPDF) peaks. Our study shows the presence of the LPDF, well visible at the deep seafloor sites, and seasonal variations of the LPDF and the SPDF amplitudes ratio, suggesting that the SPDF depends on the sea wave regime generated by local winds. For the deep seafloor sites we can also appreciate the contribution of infragravity waves (<0.05Hz). Our observations confirm the dependence of the

  11. Extreme dry spell detection and climatology over the Mediterranean Basin during the wet season

    NASA Astrophysics Data System (ADS)

    Raymond, Florian; Ullmann, Albin; Camberlin, Pierre; Drobinski, Philippe; Smith, Carmela Chateau

    2016-07-01

    The E-OBS precipitation gridded data set v.10.0 is used to detect very long dry spell (VLDS) events over the entire Mediterranean Basin for the 1957-2013 period, during the wet season (September to April). The main objective is to characterize these events as climatic objects, in terms of location, spatial extent, duration, and temporal variability. In this study, 76 VLDS events were detected in the Mediterranean Basin and grouped into four spatial patterns: scattered localized (with 25 events), northeast Mediterranean (11 events), West Mediterranean (15 events), and southeast Mediterranean (25 events). Each pattern shows seasonality in events. Most of the scattered localized, northeast, and southeast events begin in September, at the beginning of the wet season. In contrast, most of the West Mediterranean events begin in the middle of the wet season. Over time, there is a slight but not significant increase in the cumulative number of days per season affected by VLDS events.

  12. Seismicity of the Earth 1900‒2013 Mediterranean Sea and vicinity

    USGS Publications Warehouse

    Herman, Matthew W.; Hayes, Gavin P.; Smoczyk, Gregory M.; Turner, Rebecca; Turner, Bethan; Jenkins, Jennifer; Davies, Sian; Parker, Amy; Sinclair, Allison; Benz, Harley M.; Furlong, Kevin P.; Villaseñor, Antonio

    2015-09-08

    The Mediterranean region is seismically active due to the convergence of the Africa Plate with the Eurasia plate. Present day Africa-Eurasia motion ranges from ~4 millimeters per year (mm/yr) in a northwest-southeast direction in the western Mediterranean to ~10 mm/yr (north-south) in the eastern Mediterranean. The Africa-Eurasia plate boundary is complex, and includes extensional and translational zones in addition to the dominant convergent regimes characterized by subduction and continental collision. This convergence began at approximately 50 million years ago and was associated with the closure of the Tethys Sea; the Mediterranean Sea is all that remains of the Tethys. The highest rates of seismicity in the Mediterranean region are found along the Hellenic subduction zone of southern Greece and the North Anatolian Fault Zone of northwestern Turkey, but significant rates of current seismicity and large historical earthquakes have occurred throughout the region spanning the Mediterranean Sea.

  13. Seismicity of the Earth 1900‒2013 Mediterranean Sea and vicinity

    USGS Publications Warehouse

    Herman, Matthew W.; Hayes, Gavin P.; Smoczyk, Gregory M.; Turner, Rebecca; Turner, Bethan; Jenkins, Jennifer; Davies, Sian; Parker, Amy; Sinclair, Allison; Benz, Harley M.; Furlong, Kevin P.; Villaseñor, Antonio

    2015-01-01

    The Mediterranean region is seismically active due to the convergence of the Africa Plate with the Eurasia plate. Present day Africa-Eurasia motion ranges from ~4 millimeters per year (mm/yr) in a northwest-southeast direction in the western Mediterranean to ~10 mm/yr (north-south) in the eastern Mediterranean. The Africa-Eurasia plate boundary is complex, and includes extensional and translational zones in addition to the dominant convergent regimes characterized by subduction and continental collision. This convergence began at approximately 50 million years ago and was associated with the closure of the Tethys Sea; the Mediterranean Sea is all that remains of the Tethys. The highest rates of seismicity in the Mediterranean region are found along the Hellenic subduction zone of southern Greece and the North Anatolian Fault Zone of northwestern Turkey, but significant rates of current seismicity and large historical earthquakes have occurred throughout the region spanning the Mediterranean Sea.

  14. High-resolution neodymium characterization along the Mediterranean margins and modelling of ɛNd distribution in the Mediterranean basins

    NASA Astrophysics Data System (ADS)

    Ayache, Mohamed; Dutay, Jean-Claude; Arsouze, Thomas; Révillon, Sidonie; Beuvier, Jonathan; Jeandel, Catherine

    2016-09-01

    An extensive compilation of published neodymium (Nd) concentrations and isotopic compositions (Nd IC) was realized in order to establish a new database and a map (using a high-resolution geological map of the area) of the distribution of these parameters for all the Mediterranean margins. Data were extracted from different kinds of samples: river solid discharge deposited on the shelf, sedimentary material collected on the margin or geological material outcropping above or close to a margin. Additional analyses of surface sediments were done in order to improve this data set in key areas (e.g. Sicilian strait). The Mediterranean margin Nd isotopic signatures vary from non-radiogenic values around the Gulf of Lion, (ɛNd values ˜ -11) to radiogenic values around the Aegean and the Levantine sub-basins up to +6. Using a high-resolution regional oceanic model (1/12° of horizontal-resolution), ɛNd distribution was simulated for the first time in the Mediterranean Sea. The high resolution of the model provides a unique opportunity to represent a realistic thermohaline circulation in the basin and thus apprehend the processes governing the Nd isotope distribution in the marine environment. Results are consistent with the preceding conclusions on boundary exchange (BE) as an important process in the Nd oceanic cycle. Nevertheless this approach simulates a too-radiogenic value in the Mediterranean Sea; this bias will likely be corrected once the dust and river inputs will be included in the model. This work highlights that a significant interannual variability of ɛNd distribution in seawater could occur. In particular, important hydrological events such as the Eastern Mediterranean Transient (EMT), associated with deep water formed in the Aegean sub-basin, could induce a shift in ɛNd at deep/intermediate depths that could be noticeable in the eastern part of the basin. This underlines that the temporal and geographical variations of ɛNd could represent an interesting

  15. Mediterranean Diet Pyramid: A Proposal for Italian People

    PubMed Central

    D’Alessandro, Annunziata; De Pergola, Giovanni

    2014-01-01

    Bread was a staple in the traditional Mediterranean diet of the early 1960s, as well as nowadays; however, it was a stone ground sourdough bread in Nicotera and probably in the Greek cohorts of the Seven Countries Study. In the present review, the nutritional characteristics of this food are analyzed in relation to its protective effects on coronary heart disease, metabolic diseases and cancer. According to our traditions, cultural heritage and scientific evidence, we propose that only cereal foods with low glycemic index (GI) and rich in fiber have to be placed at the base of the Mediterranean diet pyramid, whereas refined grains and high GI starchy foods have to be sited at the top. PMID:25325250

  16. Mediterranean diet pyramid: a proposal for Italian people.

    PubMed

    D'Alessandro, Annunziata; De Pergola, Giovanni

    2014-10-16

    Bread was a staple in the traditional Mediterranean diet of the early 1960s, as well as nowadays; however, it was a stone ground sourdough bread in Nicotera and probably in the Greek cohorts of the Seven Countries Study. In the present review, the nutritional characteristics of this food are analyzed in relation to its protective effects on coronary heart disease, metabolic diseases and cancer. According to our traditions, cultural heritage and scientific evidence, we propose that only cereal foods with low glycemic index (GI) and rich in fiber have to be placed at the base of the Mediterranean diet pyramid, whereas refined grains and high GI starchy foods have to be sited at the top.

  17. Mediterranean Biomes: Evolution of their Vegetation, Floras and Climate

    USGS Publications Warehouse

    Rundel, Philip W.; Arroyo, Mary T.K.; Cowling, R.M.; Keeley, J. E.; Lamont, B.B.; Vargas, Pablo

    2016-01-01

    Mediterranean-type ecosystems (MTEs) possess the highest levels of plant species richness in the world outside of the wet tropics. Sclerophyll vegetation similar to today’s mediterranean-type shrublands was already present on oligotrophic soils in the wet and humid climate of the Cretaceous, with fire-adapted Paleogene lineages in southwestern Australia and the Cape Region. The novel MTC seasonality present since the mid-Miocene has allowed colonization of MTEs from a regional species pool with associated diversification. Fire persistence has been a primary driving factor for speciation in four of the five regions. Understanding the regional patterns of plant species diversity among the MTEs involves complex interactions of geologic and climatic histories for each region as well as ecological factors that have promoted diversification in the Neogene and Quaternary. A critical element of species richness for many MTE lineages has been their ability to speciate and persist at fine spatial scales, with low rates of extinction.

  18. [Familial Mediterranean fever--from gene test to clinical aspects].

    PubMed

    Sudeck, H

    2000-10-26

    Familial Mediterranean Fever (FMF) is a genetically defined disease affecting mostly families of jewish, turkish or armenian origin whose ancestors originate from the mediterranean basin. The first officially acknowledged description was given by SIEGAL in 1945 but previous cases were reported since 1908. The main clinical signs which are very varying in intensity and appearance are periodic attacks of fever with peritonitis, pleurisy and arthritis. The classical but not always found complication is amyloidosis with renal failure which is preventable by lifelong colchicine therapy. By using a novel genetest it is now possible to definitely diagnose FMF instead of relying on a diagnosis made merely by exclusion. This will emphasize the use of colchicine and should bring us nearer to the pathophysiology of this interesting disease. PMID:11103618

  19. Abrupt climate shift in the Western Mediterranean Sea

    PubMed Central

    Schroeder, K.; Chiggiato, J.; Bryden, H. L.; Borghini, M.; Ben Ismail, S.

    2016-01-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected. PMID:26965790

  20. Floating plastic debris in the Central and Western Mediterranean Sea.

    PubMed

    Ruiz-Orejón, Luis F; Sardá, Rafael; Ramis-Pujol, Juan

    2016-09-01

    In two sea voyages throughout the Mediterranean (2011 and 2013) that repeated the historical travels of Archduke Ludwig Salvator of Austria (1847-1915), 71 samples of floating plastic debris were obtained with a Manta trawl. Floating plastic was observed in all the sampled sites, with an average weight concentration of 579.3 g dw km(-2) (maximum value of 9298.2 g dw km(-2)) and an average particle concentration of 147,500 items km(-2) (the maximum concentration was 1,164,403 items km(-2)). The plastic size distribution showed microplastics (<5 mm) in all the samples. The most abundant particles had a surface area of approximately 1 mm(2) (the mesh size was 333 μm). The general estimate obtained was a total value of 1455 tons dw of floating plastic in the entire Mediterranean region, with various potential spatial accumulation areas. PMID:27540696

  1. Was Mediterranean region that dry during the Messinian Salinity Crisis?

    NASA Astrophysics Data System (ADS)

    Vasiliev, Iuliana; Mezger, Eveline; Lugli, Stefano; Reichart, Gert-Jan; Manzi, Vinicio; Roveri, Marco

    2016-04-01

    Between 5.97-5.33 Ma kilometres-thick evaporite units were deposited in the Mediterranean basin during an event known as the Messinian salinity crisis (MSC). It is generally accepted that the MSC was a dry period, with higher evaporation than precipitation and runoff. However, how dry climate was during the MSC is difficult to assess because a modern analogue is missing. Here we reconstruct hydrological changes in the Mediterranean basin during the MSC using excellently preserved biomarkers extracted from three reference sections for the Messinian evaporites: Monte Tondo, in the northern Apennines, Realmonte salt mine and Eraclea Minoa, in Sicily that cover the main stages of the MSC: the 'Primary Lower Gypsum' (stage 1 of the MSC), halite unit (stage 2) and 'Upper Gypsum' (stage 3) respectively. We used long chain n-alkanes with a strong odd over even predominance as terrestrial biomarkers, and their hydrogen isotopic values (δD) to reconstruct the large scale hydrological changes on the land adjacent to the Mediterranean covering ˜640 kyrs of the MSC interval. Additionally, the δD record of long-chain alkenones produced by haptophyte algae is used to observe changes in the source for the Mediterranean Sea water. The δDof thelong-chain n-alkanes recorded during the deposition of Lower Evaporites in Monte Tondo (MSC stage 1) indicate a δD of the precipitation largely similar to the present-day Mediterranean. This implies that the overall hydrologic regime was similar to today, with only some levels being more δD enriched (i.e. more arid/warmer). Enriched δD values of the alkenones from halite unit of the Realmonte mine (MSC stage 2) are associated with kainite (mineral forming under extreme evaporation) and giant polygons (evidence of an exposure surface), in line with the high evaporative conditions during halite deposition. The δDof thelong-chain n-alkanes recorded during the deposition of Upper Evaporites in Eraclea Minoa (MSC stage 3) indicate a δD of

  2. Modelling ozone stomatal flux of wheat under mediterranean conditions

    NASA Astrophysics Data System (ADS)

    González-Fernández, I.; Bermejo, V.; Elvira, S.; de la Torre, D.; González, A.; Navarrete, L.; Sanz, J.; Calvete, H.; García-Gómez, H.; López, A.; Serra, J.; Lafarga, A.; Armesto, A. P.; Calvo, A.; Alonso, R.

    2013-03-01

    Correct estimation of leaf-level stomatal conductance (gsto) is central for current ozone (O3) risk assessment of wheat yield loss based on the absorbed O3 phytotoxic dose (POD). The gsto model parameterizations developed in Europe must be checked in the different climatic regions where they are going to be applied in order to reduce the uncertainties associated with the POD approach. This work proposes a new gsto model parameterization for estimating POD of Triticum aestivum and Triticum durum under Mediterranean conditions, based on phenological observations over 25 years and gsto field measurements during 5 growing seasons. Results show that POD in the Mediterranean area might be higher than previously estimated. However, caution must be paid when assessing the risk of yield loss for wheat in this area since field validation of O3 impacts is still limited.

  3. Seafloor imagery from the BIG'95 debris flow, western Mediterranean

    NASA Astrophysics Data System (ADS)

    Lastras, G.; Canals, M.; Hughes-Clarke, J. E.; Moreno, A.; de Batist, M.; Masson, D. G.; Cochonat, P.

    2002-10-01

    Seafloor backscatter data are used to image the product of one of the youngest major mass-wasting events in the northwestern Mediterranean Sea: a 26 km3 debris-flow deposit that covers 2000 km2 of the Ebro continental slope and base of slope, offshore Spain. Backscatter images provide unprecedented insights on debris-flow dynamics in the deep sea. A pattern of low-backscatter patches represents large sediment blocks that moved while keeping their internal coherence. High-backscatter alignments restricted to topographic lows that represent coarse sediment pathways separate the blocks. The results presented prove the occurrence of large catastrophic sediment failures near heavily populated coastal areas even in continental margins considered to be geodynamically quiet, such as those of the northwestern Mediterranean.

  4. Mediterranean diet pyramid: a proposal for Italian people.

    PubMed

    D'Alessandro, Annunziata; De Pergola, Giovanni

    2014-10-01

    Bread was a staple in the traditional Mediterranean diet of the early 1960s, as well as nowadays; however, it was a stone ground sourdough bread in Nicotera and probably in the Greek cohorts of the Seven Countries Study. In the present review, the nutritional characteristics of this food are analyzed in relation to its protective effects on coronary heart disease, metabolic diseases and cancer. According to our traditions, cultural heritage and scientific evidence, we propose that only cereal foods with low glycemic index (GI) and rich in fiber have to be placed at the base of the Mediterranean diet pyramid, whereas refined grains and high GI starchy foods have to be sited at the top. PMID:25325250

  5. Reducing maternal mortality in the eastern Mediterranean region.

    PubMed

    Mahaini, R; Mahmoud, H

    2005-07-01

    Current efforts in some countries of the Eastern Mediterranean Region are still insufficient to achieve the fifth Millennium Development Goal on improving maternal health. Strong commitment, intensive efforts and effective national policies and strategies are now urgently required in order to translate vision into action. Such efforts and plans should target the strengthening of health systems, the expansion in the coverage of effective integrated interventions, and the recognition of the essential role of individuals, families and communities in making pregnancy safer. This article provides a background on the current situation of maternal health in the Eastern Mediterranean Region, including underlying causes and contributing factors, and describes strategic directions aimed at accelerating the reduction of maternal mortality in the Region and moving closer to the achievement of the Millennium Development Goals.

  6. Abyssal undular vortices in the Eastern Mediterranean basin.

    PubMed

    Rubino, A; Falcini, F; Zanchettin, D; Bouche, V; Salusti, E; Bensi, M; Riccobene, G; De Bonis, G; Masullo, R; Simeone, F; Piattelli, P; Sapienza, P; Russo, S; Platania, G; Sedita, M; Reina, P; Avolio, R; Randazzo, N; Hainbucher, D; Capone, A

    2012-05-15

    Abyssal temperature and velocity observations performed within the framework of the Neutrino Mediterranean Observatory, a project devoted to constructing a km(3)-scale underwater telescope for the detection of high-energy cosmic neutrinos, demonstrate cross-fertilization between subnuclear physics and experimental oceanography. Here we use data collected south of Sicily in the Ionian abyssal plain of the Eastern Mediterranean (EM) basin to show for the first time that abyssal vortices exist in the EM, at depths exceeding 2,500 m. The eddies consist of chains of near-inertially pulsating mesoscale cyclones/anticyclones. They are embedded in an abyssal current flowing towards North-Northwest. The paucity of existing data does not allow for an unambiguous determination of the vortex origin. A local generation mechanism seems probable, but a remote genesis cannot be excluded a priori. The presence of such eddies adds further complexity to the discussion of structure and evolution of water masses in the EM.

  7. Abrupt climate shift in the Western Mediterranean Sea.

    PubMed

    Schroeder, K; Chiggiato, J; Bryden, H L; Borghini, M; Ben Ismail, S

    2016-01-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected. PMID:26965790

  8. Abrupt climate shift in the Western Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Schroeder, K.; Chiggiato, J.; Bryden, H. L.; Borghini, M.; Ben Ismail, S.

    2016-03-01

    One century of oceanographic measurements has evidenced gradual increases in temperature and salinity of western Mediterranean water masses, even though the vertical stratification has basically remained unchanged. Starting in 2005, the basic structure of the intermediate and deep layers abruptly changed. We report here evidence of reinforced thermohaline variability in the deep western basin with significant dense water formation events producing large amounts of warmer, saltier and denser water masses than ever before. We provide a detailed chronological order to these changes, giving an overview of the new water masses and following their route from the central basin interior to the east (toward the Tyrrhenian) and toward the Atlantic Ocean. As a consequence of this climate shift, new deep waters outflowing through Gibraltar will impact the North Atlantic in terms of salt and heat input. In addition, modifications in the Mediterranean abyssal ecosystems and biogeochemical cycles are to be expected.

  9. Unusual presentation of familial Mediterranean fever: role of genetic diagnosis

    PubMed Central

    Nir-Paz, R.; Ben-Chetrit, E.; Pikarsky, E.; Hassin, D.; Hasin, Y.; Chajek-Shaul, T.

    2000-01-01

    OBJECTIVE—To describe the role of molecular analysis in the diagnosis of an unusual presentation of familial Mediterranean fever (FMF).
CASE REPORT—Two patients presenting with prolonged fever without signs and symptoms of serositis are described. FMF was diagnosed by genetic analysis, which disclosed that both patients were homozygous for the M694V mutation of the Mediterranean fever (MEFV) gene.
CONCLUSION—Molecular analysis of FMF should complement the investigation of patients with fever of unknown origin. This test enables a definite diagnosis of the disease and may promote the diagnosis and treatment of patients with an unusual or incomplete clinical picture of FMF.

 PMID:11005788

  10. Excess of (236)U in the northwest Mediterranean Sea.

    PubMed

    Chamizo, E; López-Lora, M; Bressac, M; Levy, I; Pham, M K

    2016-09-15

    In this work, we present first (236)U results in the northwestern Mediterranean. (236)U is studied in a seawater column sampled at DYFAMED (Dynamics of Atmospheric Fluxes in the Mediterranean Sea) station (Ligurian Sea, 43°25'N, 07°52'E). The obtained (236)U/(238)U atom ratios in the dissolved phase, ranging from about 2×10(-9) at 100m depth to about 1.5×10(-9) at 2350m depth, indicate that anthropogenic (236)U dominates the whole seawater column. The corresponding deep-water column inventory (12.6ng/m(2) or 32.1×10(12) atoms/m(2)) exceeds by a factor of 2.5 the expected one for global fallout at similar latitudes (5ng/m(2) or 13×10(12) atoms/m(2)), evidencing the influence of local or regional (236)U sources in the western Mediterranean basin. On the other hand, the input of (236)U associated to Saharan dust outbreaks is evaluated. An additional (236)U annual deposition of about 0.2pg/m(2) based on the study of atmospheric particles collected in Monaco during different Saharan dust intrusions is estimated. The obtained results in the corresponding suspended solids collected at DYFAMED station indicate that about 64% of that (236)U stays in solution in seawater. Overall, this source accounts for about 0.1% of the (236)U inventory excess observed at DYFAMED station. The influence of the so-called Chernobyl fallout and the radioactive effluents produced by the different nuclear installations allocated to the Mediterranean basin, might explain the inventory gap, however, further studies are necessary to come to a conclusion about its origin.

  11. Mercury in the Mediterranean. Part 2: processes and mass balance.

    PubMed

    Žagar, Dušan; Sirnik, Nataša; Četina, Matjaž; Horvat, Milena; Kotnik, Jože; Ogrinc, Nives; Hedgecock, Ian M; Cinnirella, Sergio; De Simone, Francesco; Gencarelli, Christian N; Pirrone, Nicola

    2014-03-01

    Mass balance of contaminants can provide useful information on the processes that influence their concentrations in various environmental compartments. The most important sources, sinks and the equilibrium or non-equilibrium state of the contaminant in individual environmental compartments can also be identified. Using the latest mercury speciation data, the results of numerical models and the results of recent studies on mercury transport and transformation processes in the marine environment, we have re-evaluated the total mercury (HgT) mass balance in the Mediterranean Sea. New calculations have been performed employing three distinct marine layers: the surface layer, the thermocline and the deep sea. New transport mechanisms, deep water formation and density-driven sinking and upwelling, were included in the mass balance calculations. The most recent data have even enabled the calculation of an approximate methylmercury (MeHg) mass balance. HgT is well balanced in the entire Mediterranean, and the discrepancies between inputs and outputs in individual layers do not exceed 20 %. The MeHg balance shows larger discrepancies between gains and losses due to measurement uncertainties and gaps in our knowledge of Hg species transformation processes. Nonetheless, the main sources and sinks of HgT (deposition and evasion) and MeHg (fluxes from sediment, outflow through the Gibraltar Strait) are in accordance with previous studies on mercury in the Mediterranean Basin. Mercury in the Mediterranean fish harvest is the second largest MeHg sink; about 300 kg of this toxic substance is consumed annually with sea food.

  12. Excess of (236)U in the northwest Mediterranean Sea.

    PubMed

    Chamizo, E; López-Lora, M; Bressac, M; Levy, I; Pham, M K

    2016-09-15

    In this work, we present first (236)U results in the northwestern Mediterranean. (236)U is studied in a seawater column sampled at DYFAMED (Dynamics of Atmospheric Fluxes in the Mediterranean Sea) station (Ligurian Sea, 43°25'N, 07°52'E). The obtained (236)U/(238)U atom ratios in the dissolved phase, ranging from about 2×10(-9) at 100m depth to about 1.5×10(-9) at 2350m depth, indicate that anthropogenic (236)U dominates the whole seawater column. The corresponding deep-water column inventory (12.6ng/m(2) or 32.1×10(12) atoms/m(2)) exceeds by a factor of 2.5 the expected one for global fallout at similar latitudes (5ng/m(2) or 13×10(12) atoms/m(2)), evidencing the influence of local or regional (236)U sources in the western Mediterranean basin. On the other hand, the input of (236)U associated to Saharan dust outbreaks is evaluated. An additional (236)U annual deposition of about 0.2pg/m(2) based on the study of atmospheric particles collected in Monaco during different Saharan dust intrusions is estimated. The obtained results in the corresponding suspended solids collected at DYFAMED station indicate that about 64% of that (236)U stays in solution in seawater. Overall, this source accounts for about 0.1% of the (236)U inventory excess observed at DYFAMED station. The influence of the so-called Chernobyl fallout and the radioactive effluents produced by the different nuclear installations allocated to the Mediterranean basin, might explain the inventory gap, however, further studies are necessary to come to a conclusion about its origin. PMID:27262827

  13. Mediterranean diet in healthy lifestyle and prevention of stroke.

    PubMed

    Demarin, Vida; Lisak, Marijana; Morović, Sandra

    2011-03-01

    Several studies demonstrated the beneficial and preventive role of Mediterranean diet in the occurrence of cardiovascular diseases, chronic neurodegenerative diseases and neoplasms, obesity and diabetes. In randomized intervention trials, Mediterranean diet improved endothelial function and significantly reduced waist circumference, plasma glucose, serum insulin and homeostasis model assessment score in metabolic syndrome. Several studies support favorable effects of Mediterranean diet on plasma lipid profile: reduction of total and plasma LDL cholesterol levels, plasma triglyceride levels, and apo-B and VLDL concentrations, and an increase in plasma HDL cholesterol levels. This effect is associated with increased plasma antioxidant capacity, improved endothelial function, reduced insulin resistance, and reduced incidence of the metabolic syndrome. The beneficial impact of fish consumption on the risk of cardiovascular diseases is the result of synergistic effects of nutrients in fish. Fish is considered an excellent source of protein with low saturated fat, nutritious trace elements, long-chain omega-3 polyunsaturated fatty acids (LCn3PUFAs), and vitamins D and B. Fish consumption may be inversely associated with ischemic stroke but not with hemorrhagic stroke because of the potential antiplatelet aggregation property of LCn3PUFAs. Total stroke risk reduction was statistically significant for fish intake once per week, while the risk of stroke was lowered by 31% in individuals who ate fish 5 times or more per week. In the elderly, moderate consumption of tuna/other fish, but not fried fish, was associated with lower prevalence of subclinical infarcts and white matter abnormalities on MRI examination. Dietary intake of omega-3 fatty acids in a moderate-to-high range does not appear to be associated with reduced plaque, but is negatively associated with carotid artery intima-media thickness. Greater adherence to Mediterranean diet is associated with significant

  14. High-resolution sea wind hindcasts over the Mediterranean area

    NASA Astrophysics Data System (ADS)

    Menendez, M.; García-Díez, M.; Fita, L.; Fernández, J.; Méndez, F. J.; Gutiérrez, J. M.

    2014-04-01

    The goal of this study is to develop a high-resolution atmospheric hindcast over the Mediterranean area using the WRF-ARW model, focusing on offshore surface wind fields. In order to choose the most adequate model configuration, the study provides details on the calibration of the experimental saet-up through a sensitivity test considering the October-December 2001 period (the 2001 super-storm event in the West Mediterranean). A daily forecast outperforms the spectral technique of previous products and the boundary data from ERA-Interim reanalysis produces the most accurate estimates in terms of wind variability and hour-to-hour correspondence. According to the sensitivity test, two data sets of wind hindcast are produced: the SeaWind I (30-km horizontal resolution for a period of 60 years) and the SeaWind II (15-km horizontal resolution for 20 years). The validation of the resulting surface winds is undertaken considering two offshore observational datasets. On the one hand, hourly surface buoy stations are used to validate wind time series at specific locations; on the other hand, wind altimeter satellite observations are considered for spatial validation in the whole Mediterranean Sea. The results obtained from this validation process show a very good agreement with observations for the southern Europe region. Finally, SeaWind I and II are used to characterize offshore wind fields in the Mediterranean Sea. The statistical structure of sea surface wind is analyzed and the agreement with Weibull probability distribution is discussed. In addition, wind persistence and extreme wind speed (50 year return period) are characterized and relevant areas of wind power generation are described by estimating wind energy quantities.

  15. Vortices generation mechanisms in North western Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Fraunie, P.; Redondo, J. M.; Schaeffer, A.; Molcard, A.; Forget, P.; Garreau, P.

    2012-04-01

    Mesoscale eddies have been observed in Northwestern Mediterranean Sea from satellites, RV cruises and more recently using HF radars. Different non linear mechanisms have been identified and investigated using process oriented high resolution numerical modelling. In particular, wind induced inertial motion and baroclinic instability cases have been illustrated and documented. Statistics of vortices occurence allow a better accounting for coherent structures for pollutants and nutriments dispersion and retention. Acknowledgements : GIRAC project (FUI - CG83 -TPM), ESA, HYMEX programme

  16. Hydroclimatic and water quality trends across three Mediterranean river basins.

    PubMed

    Lutz, Stefanie R; Mallucci, Stefano; Diamantini, Elena; Majone, Bruno; Bellin, Alberto; Merz, Ralf

    2016-11-15

    Water resources are under pressure from multiple anthropogenic stressors such as changing climate, agriculture and water abstraction. This holds, in particular, for the Mediterranean region, where substantial changes in climate are expected throughout the 21st century. Nonetheless, little attention has been paid to linkages between long-term trends in climate, streamflow and water quality in Mediterranean river basins. In the present study, we perform a comparative analysis of recent trends in hydroclimatic parameters and nitrate pollution in three climatologically different Mediterranean watersheds (i.e., the Adige, Ebro and Sava River Basins). Mann-Kendall trend analyses of annual mean temperature, precipitation and streamflow (period 1971 to 2010) and monthly nitrate concentrations, mass fluxes and flow-adjusted concentrations (period 1996 to 2012) were performed in these river basins. Temperature is shown to have increased the most in the Ebro followed by the Sava, whereas minor increases are observed in the Adige. Precipitation presents, overall, a negative trend in the Ebro and a positive trend in both the Adige and Sava. These climatic trends thus suggest the highest risk of increasing water scarcity for the Ebro and the lowest risk for the Adige. This is confirmed by trend analyses of streamflow time series, which indicate a severe decline in streamflow for the Ebro and a substantial decline in the Sava, as opposed to the Adige showing no prevailing trend. Concerning surface water quality, nitrate pollution appears to have decreased in all study basins. Overall, these findings emphasize progressive reduction of water resources availability in river basins characterized by continental climate (i.e., Ebro and Sava). This study thus underlines the need for adapted river management in the Mediterranean region, particularly considering strong feedbacks between hydroclimatic trends, freshwater ecosystem services and water resources availability for agriculture

  17. Rainfall, runoff and sediment transport in a Mediterranean mountainous catchment.

    PubMed

    Tuset, J; Vericat, D; Batalla, R J

    2016-01-01

    The relation between rainfall, runoff, erosion and sediment transport is highly variable in Mediterranean catchments. Their relation can be modified by land use changes and climate oscillations that, ultimately, will control water and sediment yields. This paper analyses rainfall, runoff and sediment transport relations in a meso-scale Mediterranean mountain catchment, the Ribera Salada (NE Iberian Peninsula). A total of 73 floods recorded between November 2005 and November 2008 at the Inglabaga Sediment Transport Station (114.5 km(2)) have been analysed. Suspended sediment transport and flow discharge were measured continuously. Rainfall data was obtained by means of direct rain gauges and daily rainfall reconstructions from radar information. Results indicate that the annual sediment yield (2.3 t km(-1) y(-1) on average) and the flood-based runoff coefficients (4.1% on average) are low. The Ribera Salada presents a low geomorphological and hydrological activity compared with other Mediterranean mountain catchments. Pearson correlations between rainfall, runoff and sediment transport variables were obtained. The hydrological response of the catchment is controlled by the base flows. The magnitude of suspended sediment concentrations is largely correlated with flood magnitude, while sediment load is correlated with the amount of direct runoff. Multivariate analysis shows that total suspended load can be predicted by integrating rainfall and runoff variables. The total direct runoff is the variable with more weight in the equation. Finally, three main hydro-sedimentary phases within the hydrological year are defined in this catchment: (a) Winter, where the catchment produces only water and very little sediment; (b) Spring, where the majority of water and sediment is produced; and (c) Summer-Autumn, when little runoff is produced but significant amount of sediments is exported out of the catchment. Results show as land use and climate change may have an important

  18. Adherence to Mediterranean diet in a Spanish university population.

    PubMed

    García-Meseguer, María José; Burriel, Faustino Cervera; García, Cruz Vico; Serrano-Urrea, Ramón

    2014-07-01

    The aim of this work was to characterize food habits of Spanish University students and to assess the quality of their diet and some possible determinant factors according to Mediterranean food pattern among other indices. Two hundred eighty-four enrolled students during the academic year 2012-2013 participated in this survey. For each individual a questionnaire involving anthropometric measurements, types of housing, smoking habits and levels of physical activity were self-reported. Food consumption was gathered by two nonconsecutive 24 hour recalls including one weekend day. BMI within the normal range was showed by 72.5% of students and 75% of the sample reflected a sedentary lifestyle or low physical activity. The percentage of total energy from each macronutrient was approximately 17% proteins, 40% carbohydrates and 40% lipids. The ratio of polyunsaturated to monounsaturated fat only reached 0.32. Cholesterol consumption in men exceeded the intake in women by 70 mg/day but nutritional objectives were exceeded in both genders. The main source of protein had an animal origin from meat (38.1%), followed by cereals (19.4%) and dairy products (15.6%). The assessment of diet quality conducted by Healthy Eating Index (HEI) and Mediterranean Diet Score (MDS) revealed a low-intermediate score in both (51.2 ± 12.8 and 4.0 ± 1.5, respectively). The main deviations from Mediterranean pattern were a low intake of vegetables and fruit and a high consumption of meat and dairy products. According to HEI classification, 96.1% of subjects scored "poor" or "needs improvement" about the quality of their diet and only 5.3% of students achieved a high adherence to Mediterranean diet. It is necessary to foster changes toward a healthier diet pattern according to cultural context in this population for preventing cardiovascular diseases, type 2 diabetes and insulin resistance.

  19. Rainfall, runoff and sediment transport in a Mediterranean mountainous catchment.

    PubMed

    Tuset, J; Vericat, D; Batalla, R J

    2016-01-01

    The relation between rainfall, runoff, erosion and sediment transport is highly variable in Medit